1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [f61fa984-3bb4-4499-a749-7903a576eb94] => Array
        (
            [runtime-id] => f61fa984-3bb4-4499-a749-7903a576eb94
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [7f7057a9-22a6-4692-863a-bfbed182acf6] => Array
                        (
                            [runtime-id] => 7f7057a9-22a6-4692-863a-bfbed182acf6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [352d4fdd-0eb9-42a5-95f5-321ea4f12826] => Array
        (
            [runtime-id] => 352d4fdd-0eb9-42a5-95f5-321ea4f12826
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [92ba20fa-c6ed-4f45-969f-acff1c918b20] => Array
                        (
                            [runtime-id] => 92ba20fa-c6ed-4f45-969f-acff1c918b20
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [d9457708-da8d-48c5-bed2-cb0c7e6e0c36] => Array
        (
            [runtime-id] => d9457708-da8d-48c5-bed2-cb0c7e6e0c36
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [8b115d3a-d867-453b-a3d0-0601424906b6] => Array
                        (
                            [runtime-id] => 8b115d3a-d867-453b-a3d0-0601424906b6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [54dbcd4d-9e58-42e8-8b91-bf053bc3efee] => Array
        (
            [runtime-id] => 54dbcd4d-9e58-42e8-8b91-bf053bc3efee
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [412b8de2-f0f0-4bcb-98e5-ed3b2a3628fd] => Array
                        (
                            [runtime-id] => 412b8de2-f0f0-4bcb-98e5-ed3b2a3628fd
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [f61fa984-3bb4-4499-a749-7903a576eb94] => Array
        (
            [runtime-id] => f61fa984-3bb4-4499-a749-7903a576eb94
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [7f7057a9-22a6-4692-863a-bfbed182acf6] => Array
                        (
                            [runtime-id] => 7f7057a9-22a6-4692-863a-bfbed182acf6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [f61fa984-3bb4-4499-a749-7903a576eb94] => Array
        (
            [runtime-id] => f61fa984-3bb4-4499-a749-7903a576eb94
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [7f7057a9-22a6-4692-863a-bfbed182acf6] => Array
                        (
                            [runtime-id] => 7f7057a9-22a6-4692-863a-bfbed182acf6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [f61fa984-3bb4-4499-a749-7903a576eb94] => Array
        (
            [runtime-id] => f61fa984-3bb4-4499-a749-7903a576eb94
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [7f7057a9-22a6-4692-863a-bfbed182acf6] => Array
                        (
                            [runtime-id] => 7f7057a9-22a6-4692-863a-bfbed182acf6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [f61fa984-3bb4-4499-a749-7903a576eb94] => Array
        (
            [runtime-id] => f61fa984-3bb4-4499-a749-7903a576eb94
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => Controlled
            [privilege] => Array
                (
                    [7f7057a9-22a6-4692-863a-bfbed182acf6] => Array
                        (
                            [runtime-id] => 7f7057a9-22a6-4692-863a-bfbed182acf6
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
1naresh2naresh<pre>Array
(
    [urn:ac.highwire.org:guest:identity] => Array
        (
            [runtime-id] => urn:ac.highwire.org:guest:identity
            [type] => guest
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [urn:ac.highwire.org:guest:privilege] => Array
                        (
                            [runtime-id] => urn:ac.highwire.org:guest:privilege
                            [type] => privilege-set
                            [privilege-set] => GUEST
                        )

                )

            [credentials] => Array
                (
                    [method] => guest
                )

        )

    [61be646d-96c1-418f-bc61-29a72573c68a] => Array
        (
            [runtime-id] => 61be646d-96c1-418f-bc61-29a72573c68a
            [type] => toll-free-key
            [service-id] => ajnr-ac.highwire.org
            [access-type] => FreeToRead
            [privilege] => Array
                (
                    [449ad248-6bf0-4797-9214-476d4f2f8363] => Array
                        (
                            [runtime-id] => 449ad248-6bf0-4797-9214-476d4f2f8363
                            [type] => toll-free-key
                        )

                )

            [credentials] => Array
                (
                    [method] => toll-free-key
                    [value] => tf_ipsecsha;667606eda2644a4cb529640daa45fb0523977441
                )

        )

)
<!DOCTYPE html>
<html lang="en" dir="ltr" 
  xmlns="http://www.w3.org/1999/xhtml"
  xmlns:mml="http://www.w3.org/1998/Math/MathML">
  <head prefix="og: http://ogp.me/ns# article: http://ogp.me/ns/article# book: http://ogp.me/ns/book#" >
    <!--[if IE]><![endif]-->
<link rel="dns-prefetch" href="//securepubads.g.doubleclick.net" />
<link rel="dns-prefetch" href="//scholar.google.com" />
<link rel="dns-prefetch" href="//cdn.jsdelivr.net" />
<link rel="dns-prefetch" href="//www.google.com" />
<link rel="dns-prefetch" href="//www.googletagmanager.com" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<link rel="shortlink" href="/node/9880" />
<meta name="Generator" content="Drupal 7 (http://drupal.org)" />
<link rel="shortcut icon" href="http://ajnr-stage2.stage.highwire.org/sites/default/files/images/favicon.ico" type="image/vnd.microsoft.icon" />
<meta name="issue_cover_image" content="http://ajnr-stage2.stage.highwire.org/sites/default/files/highwire/ajnr/31/5.cover.gif" />
<meta name="type" content="article" />
<meta name="category" content="research-article" />
<meta name="HW.identifier" content="/ajnr/31/5/838.atom" />
<meta name="HW.pisa" content="ajnr;31/5/838" />
<meta name="DC.Format" content="text/html" />
<meta name="DC.Language" content="en" />
<meta name="DC.Title" content="Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images" />
<meta name="DC.Identifier" content="10.3174/ajnr.A1941" />
<meta name="DC.Date" content="2010-05-01" />
<meta name="DC.Publisher" content="American Journal of Neuroradiology" />
<meta name="DC.Rights" content="Copyright © American Society of Neuroradiology" />
<meta name="DC.AccessRights" content="restricted" />
<meta name="DC.Description" content="BACKGROUND AND PURPOSE: The ADI is the imaging diagnostic clue to AAA subluxation of the cervical spine. Some MR imaging findings other than abnormal ADI relate to AAA subluxation. However, their relationship is not yet clarified. The present study elucidates the role of MR imaging by employing these previously overlooked findings.

MATERIALS AND METHODS: This study enrolled 40 patients with AAA subluxation and 20 non-AAA subluxation patients as controls. All MR imaging was performed with supine neutral positioning. The morphology of the dens, bilateral facet joints, and surrounding ligaments, as well as the alignment of the anterior atlantoaxial joint, the spinolaminar line, and the intramedullary signal intensity, were assessed. This investigation statistically analyzed the difference among these groups.

RESULTS: Thirty-eight percent (15 of 40) of patients with AAA subluxation showed nAAA. There was no significant difference between the groups of AAA with normal and abnormal ADI except that more peridental pannus was seen in the latter group. More dens erosion ( P = .022), tilting of anterior atlantoaxial joint ( P = .022), peridental effusion ( P &lt; .001), lateral facet arthropathy ( P &lt; .001), abnormal spinolaminar line ( P = .001), and focal myelopathy ( P = .001) were observed in nAAA patients compared with the controls. The combination of peridental effusion, lateral facet arthropathy, abnormal intramedullary signals, and abnormal spinolaminar line showed a sensitivity of 100% and a specificity of 90% in diagnosing AAA subluxation.

CONCLUSIONS: MR imaging provides important biomechanical clues, other than ADI, that improve accuracy in diagnosing atlantoaxial instability.

AAA subluxation
:   anterior atlantoaxial subluxation
aAAA subluxation
:   anterior atlantoaxial subluxation with abnormal atlantodental interval
nAAA subluxation
:   anterior atlantoaxial subluxation with normal atlantodental interval
ADI
:   atlantodental interval
ALL
:   anterior longitudinal ligament
FSE
:   fast spin-echo
NS
:   not significant
PD
:   predental
RD
:   retrodental
SD
:   supradental
TM
:   tectorial membrane" />
<meta name="DC.Contributor" content="S.-C. Hung" />
<meta name="DC.Contributor" content="H.-M. Wu" />
<meta name="DC.Contributor" content="W.-Y. Guo" />
<meta name="article:published_time" content="2010-05-01" />
<meta name="article:section" content="Spine" />
<meta name="citation_title" content="Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images" />
<meta name="citation_abstract" lang="en" content="&lt;h3&gt;BACKGROUND AND PURPOSE:&lt;/h3&gt;
&lt;p&gt;The ADI is the imaging diagnostic clue to AAA subluxation of the cervical spine. Some MR imaging findings other than abnormal ADI relate to AAA subluxation. However, their relationship is not yet clarified. The present study elucidates the role of MR imaging by employing these previously overlooked findings.&lt;/p&gt;&lt;h3&gt;MATERIALS AND METHODS:&lt;/h3&gt;
&lt;p&gt;This study enrolled 40 patients with AAA subluxation and 20 non-AAA subluxation patients as controls. All MR imaging was performed with supine neutral positioning. The morphology of the dens, bilateral facet joints, and surrounding ligaments, as well as the alignment of the anterior atlantoaxial joint, the spinolaminar line, and the intramedullary signal intensity, were assessed. This investigation statistically analyzed the difference among these groups.&lt;/p&gt;&lt;h3&gt;RESULTS:&lt;/h3&gt;
&lt;p&gt;Thirty-eight percent (15 of 40) of patients with AAA subluxation showed nAAA. There was no significant difference between the groups of AAA with normal and abnormal ADI except that more peridental pannus was seen in the latter group. More dens erosion (&lt;i&gt;P&lt;/i&gt; = .022), tilting of anterior atlantoaxial joint (&lt;i&gt;P&lt;/i&gt; = .022), peridental effusion (&lt;i&gt;P&lt;/i&gt; &amp;lt; .001), lateral facet arthropathy (&lt;i&gt;P&lt;/i&gt; &amp;lt; .001), abnormal spinolaminar line (&lt;i&gt;P&lt;/i&gt; = .001), and focal myelopathy (&lt;i&gt;P&lt;/i&gt; = .001) were observed in nAAA patients compared with the controls. The combination of peridental effusion, lateral facet arthropathy, abnormal intramedullary signals, and abnormal spinolaminar line showed a sensitivity of 100% and a specificity of 90% in diagnosing AAA subluxation.&lt;/p&gt;&lt;h3&gt;CONCLUSIONS:&lt;/h3&gt;
&lt;p&gt;MR imaging provides important biomechanical clues, other than ADI, that improve accuracy in diagnosing atlantoaxial instability.&lt;/p&gt;" />
<meta name="citation_journal_title" content="American Journal of Neuroradiology" />
<meta name="citation_publisher" content="American Journal of Neuroradiology" />
<meta name="citation_publication_date" content="2010/05/01" />
<meta name="citation_mjid" content="ajnr;31/5/838" />
<meta name="citation_id" content="31/5/838" />
<meta name="citation_public_url" content="http://ajnr-stage2.stage.highwire.org/content/31/5/838" />
<meta name="citation_abstract_html_url" content="http://ajnr-stage2.stage.highwire.org/content/31/5/838.abstract" />
<meta name="citation_full_html_url" content="http://ajnr-stage2.stage.highwire.org/content/31/5/838.full" />
<meta name="citation_pdf_url" content="http://ajnr-stage2.stage.highwire.org/content/ajnr/31/5/838.full.pdf" />
<meta name="citation_issn" content="0195-6108" />
<meta name="citation_issn" content="1936-959X" />
<meta name="citation_doi" content="10.3174/ajnr.A1941" />
<meta name="citation_pmid" content="20044504" />
<meta name="citation_volume" content="31" />
<meta name="citation_issue" content="5" />
<meta name="citation_article_type" content="Research Article" />
<meta name="citation_section" content="Spine" />
<meta name="citation_firstpage" content="838" />
<meta name="citation_lastpage" content="843" />
<meta name="citation_author" content="S.-C. Hung" />
<meta name="citation_author" content="H.-M. Wu" />
<meta name="citation_author" content="W.-Y. Guo" />
<meta name="citation_reference" content="citation_journal_title=The Journal of Rheumatology;citation_journal_abbrev=The Journal of Rheumatology;citation_author=AK. Zikou;citation_author=Y. Alamanos;citation_author=MI. Argyropoulou;citation_title=Radiological cervical spine involvement in patients with rheumatoid arthritis: a cross sectional study.;citation_pages=801-806;citation_volume=32;citation_year=2005;citation_issue=5;citation_issn=0315-162X;citation_pmid=15868612" />
<meta name="citation_reference" content="citation_journal_title=Clinical and experimental rheumatology;citation_journal_abbrev=Clin Exp Rheumatol;citation_author=A. Naranjo;citation_author=L. Carmona;citation_author=D. Gavrila;citation_title=Prevalence and associated factors of anterior atlantoaxial luxation in a nation-wide sample of rheumatoid arthritis patients.;citation_pages=427-432;citation_volume=22;citation_year=2004;citation_issue=4;citation_pmid=15301239" />
<meta name="citation_reference" content="citation_journal_title=Scandinavian journal of rheumatology;citation_journal_abbrev=Scand J Rheumatol;citation_author=M. Kauppi;citation_author=M. Hakala;citation_title=Prevalence of cervical spine subluxations and dislocations in a community-based rheumatoid arthritis population.;citation_pages=133-136;citation_volume=23;citation_year=1994;citation_issue=3;citation_pmid=8016584" />
<meta name="citation_reference" content="citation_journal_title=AJNR Am J Neuroradiol ;citation_author=CA. Rojas;citation_author=JC. Bertozzi;citation_author=CR. Martinez;citation_title=Reassessment of the craniocervical junction: normal values on CT;citation_volume=28;citation_year=2007;citation_pmid=17893223;citation_doi=10.3174/ajnr.A0660" />
<meta name="citation_reference" content="citation_journal_title=Acta orthopaedica Scandinavica;citation_journal_abbrev=Acta Orthop Scand;citation_author=H. Brattstrom;citation_author=L. Granholm;citation_title=Atlanto-axial fusion in rheumatoid arthritis. A new method of fixation with wire and bone cement.;citation_pages=619-628;citation_volume=47;citation_year=1976;citation_issue=6;citation_pmid=189561" />
<meta name="citation_reference" content="citation_journal_title=Clinical rheumatology;citation_journal_abbrev=Clin Rheumatol;citation_author=M. Kauppi;citation_author=MH. Neva;citation_title=Sensitivity of lateral view cervical spine radiographs taken in the neutral position in atlantoaxial subluxation in rheumatic diseases.;citation_pages=511-514;citation_volume=17;citation_year=1998;citation_issue=6;citation_pmid=9890681;citation_doi=10.1007/BF01451289" />
<meta name="citation_reference" content="citation_journal_title=American Journal of Roentgenology;citation_journal_abbrev=Am. J. Roentgenol.;citation_author=C. Bundschuh;citation_author=MT. Modic;citation_author=F. Kearney;citation_title=Rheumatoid arthritis of the cervical spine: surface-coil MR imaging;citation_pages=181-187;citation_volume=151;citation_year=1988;citation_issue=1;citation_issn=0361-803X;citation_pmid=3259803" />
<meta name="citation_reference" content="citation_journal_title=Journal of computer assisted tomography;citation_journal_abbrev=J Comput Assist Tomogr;citation_author=V. Gupta;citation_author=N. Khandelwal;citation_author=SN. Mathuria;citation_title=Dynamic magnetic resonance imaging evaluation of craniovertebral junction abnormalities.;citation_pages=354-359;citation_volume=31;citation_year=2007;citation_issue=3;citation_pmid=17538278;citation_doi=10.1097/01.rct.0000238009.57307.26" />
<meta name="citation_reference" content="citation_journal_title=Annals of the Rheumatic Diseases;citation_journal_abbrev=Ann Rheum Dis;citation_author=K. Laiho;citation_author=I. Soini;citation_author=H. Kautiainen;citation_title=Can we rely on magnetic resonance imaging when evaluating unstable atlantoaxial subluxation?;citation_pages=254-256;citation_volume=62;citation_year=2003;citation_issue=3;citation_issn=0003-4967;citation_pmid=12594114;citation_doi=10.1136/ard.62.3.254" />
<meta name="citation_reference" content="citation_journal_title=American Journal of Roentgenology;citation_journal_abbrev=Am. J. Roentgenol.;citation_author=MA. Stiskal;citation_author=A. Neuhold;citation_author=DH. Szolar;citation_title=Rheumatoid arthritis of the craniocervical region by MR imaging: detection and characterization;citation_pages=585-592;citation_volume=165;citation_year=1995;citation_issue=3;citation_issn=0361-803X;citation_pmid=7645475" />
<meta name="citation_reference" content="citation_journal_title=Clinical biomechanics (Bristol, Avon);citation_journal_abbrev=Clin Biomech (Bristol, Avon);citation_author=N. Bogduk;citation_author=S. Mercer;citation_title=Biomechanics of the cervical spine. I: Normal kinematics.;citation_pages=633-648;citation_volume=15;citation_year=2000;citation_issue=9;citation_pmid=10946096;citation_doi=10.1016/S0268-0033(00)00034-6" />
<meta name="citation_reference" content="citation_journal_title=Clinical neurosurgery;citation_journal_abbrev=Clin Neurosurg;citation_author=MM. Panjabi;citation_author=LL. Thibodeau;citation_author=JJ. Crisco;citation_title=What constitutes spinal instability?;citation_pages=313-339;citation_volume=34;citation_year=1988;citation_pmid=3288400" />
<meta name="citation_reference" content="citation_journal_title=Journal of spinal disorders;citation_journal_abbrev=J Spinal Disord;citation_author=MM. Panjabi;citation_author=TR. Oxland;citation_author=EH. Parks;citation_title=Quantitative anatomy of cervical spine ligaments. Part I. Upper cervical spine.;citation_pages=270-276;citation_volume=4;citation_year=1991;citation_issue=3;citation_pmid=1802157" />
<meta name="citation_reference" content="citation_journal_title=Journal of neurosurgery;citation_journal_abbrev=J Neurosurg;citation_author=RS. Tubbs;citation_author=P. Grabb;citation_author=A. Spooner;citation_title=The apical ligament: anatomy and functional significance.;citation_pages=197-200;citation_volume=92;citation_year=2000;citation_issue=2 Suppl;citation_pmid=10763691" />
<meta name="citation_reference" content="citation_journal_title=The Journal of Bone and Joint Surgery;citation_journal_abbrev=JBJS;citation_author=JW. Fielding;citation_author=GB. Cochran;citation_author=JF. Lawsing;citation_title=Tears of the Transverse Ligament of the Atlas: A CLINICAL AND BIOMECHANICAL STUDY;citation_pages=1683-1691;citation_volume=56;citation_year=1974;citation_issue=8;citation_issn=0021-9355;citation_pmid=4434037" />
<meta name="citation_reference" content="citation_journal_title=American Journal of Neuroradiology;citation_journal_abbrev=Am. J. Neuroradiol.;citation_author=ER. Noble;citation_author=WR. Smoker;citation_title=The forgotten condyle: the appearance, morphology, and classification of occipital condyle fractures;citation_pages=507-513;citation_volume=17;citation_year=1996;citation_issue=3;citation_issn=0195-6108;citation_pmid=8881246" />
<meta name="citation_reference" content="citation_journal_title=Journal of the American Academy of Orthopaedic Surgeons;citation_journal_abbrev=J Am Acad Orthop Surg;citation_author=RS. Jackson;citation_author=DM. Banit;citation_author=AL. Rhyne;citation_title=Upper Cervical Spine Injuries;citation_pages=271-280;citation_volume=10;citation_year=2002;citation_issue=4;citation_issn=1067-151X;citation_pmid=15089076" />
<meta name="citation_reference" content="citation_journal_title=Journal of the Formosan Medical Association = Taiwan yi zhi;citation_journal_abbrev=J Formos Med Assoc;citation_author=S. Duan;citation_author=X. Huang;citation_author=Q. Lin;citation_title=Clinical significance of articulating facet displacement of lateral atlantoaxial joint on 3D CT in diagnosing atlantoaxial subluxation.;citation_pages=840-846;citation_volume=106;citation_year=2007;citation_issue=10;citation_pmid=17964963;citation_doi=10.1016/S0929-6646(08)60049-2" />
<meta name="citation_reference" content="citation_journal_title=Clinical radiology;citation_journal_abbrev=Clin Radiol;citation_author=D. Glew;citation_author=I. Watt;citation_author=PA. Dieppe;citation_title=MRI of the cervical spine: rheumatoid arthritis compared with cervical spondylosis.;citation_pages=71-76;citation_volume=44;citation_year=1991;citation_issue=2;citation_pmid=1884588;citation_doi=10.1016/S0009-9260(05)80498-2" />
<meta name="citation_reference" content="citation_journal_title=RadioGraphics;citation_journal_abbrev=RadioGraphics;citation_author=AV. Deliganis;citation_author=AB. Baxter;citation_author=JA. Hanson;citation_title=Radiologic Spectrum of Craniocervical Distraction Injuries;citation_pages=237S-250;citation_volume=20;citation_year=2000;citation_issue=90001;citation_issn=0271-5333;citation_pmid=11046174" />
<meta name="citation_reference" content="citation_journal_title=European radiology;citation_journal_abbrev=Eur Radiol;citation_author=C. Czerny;citation_author=S. Grampp;citation_author=CB. Henk;citation_title=Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT.;citation_pages=1416-1422;citation_volume=10;citation_year=2000;citation_issue=9;citation_pmid=10997430;citation_doi=10.1007/s003300000433" />
<meta name="twitter:title" content="Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images" />
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:image" content="http://ajnr-stage2.stage.highwire.org/sites/default/files/highwire/ajnr/31/5.cover.gif" />
<meta name="twitter:description" content="BACKGROUND AND PURPOSE: The ADI is the imaging diagnostic clue to AAA subluxation of the cervical spine. Some MR imaging findings other than abnormal ADI relate to AAA subluxation. However, their relationship is not yet clarified. The present study elucidates the role of MR imaging by employing these previously overlooked findings.

MATERIALS AND METHODS: This study enrolled 40 patients with AAA subluxation and 20 non-AAA subluxation patients as controls. All MR imaging was performed with supine neutral positioning. The morphology of the dens, bilateral facet joints, and surrounding ligaments, as well as the alignment of the anterior atlantoaxial joint, the spinolaminar line, and the intramedullary signal intensity, were assessed. This investigation statistically analyzed the difference among these groups.

RESULTS: Thirty-eight percent (15 of 40) of patients with AAA subluxation showed nAAA. There was no significant difference between the groups of AAA with normal and abnormal ADI except that more peridental pannus was seen in the latter group. More dens erosion ( P = .022), tilting of anterior atlantoaxial joint ( P = .022), peridental effusion ( P &lt; .001), lateral facet arthropathy ( P &lt; .001), abnormal spinolaminar line ( P = .001), and focal myelopathy ( P = .001) were observed in nAAA patients compared with the controls. The combination of peridental effusion, lateral facet arthropathy, abnormal intramedullary signals, and abnormal spinolaminar line showed a sensitivity of 100% and a specificity of 90% in diagnosing AAA subluxation.

CONCLUSIONS: MR imaging provides important biomechanical clues, other than ADI, that improve accuracy in diagnosing atlantoaxial instability.

AAA subluxation
:   anterior atlantoaxial subluxation
aAAA subluxation
:   anterior atlantoaxial subluxation with abnormal atlantodental interval
nAAA subluxation
:   anterior atlantoaxial subluxation with normal atlantodental interval
ADI
:   atlantodental interval
ALL
:   anterior longitudinal ligament
FSE
:   fast spin-echo
NS
:   not significant
PD
:   predental
RD
:   retrodental
SD
:   supradental
TM
:   tectorial membrane" />
<meta name="og-title" property="og:title" content="Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images" />
<meta name="og-url" property="og:url" content="http://ajnr-stage2.stage.highwire.org/content/31/5/838" />
<meta name="og-site-name" property="og:site_name" content="American Journal of Neuroradiology" />
<meta name="og-description" property="og:description" content="BACKGROUND AND PURPOSE: The ADI is the imaging diagnostic clue to AAA subluxation of the cervical spine. Some MR imaging findings other than abnormal ADI relate to AAA subluxation. However, their relationship is not yet clarified. The present study elucidates the role of MR imaging by employing these previously overlooked findings.

MATERIALS AND METHODS: This study enrolled 40 patients with AAA subluxation and 20 non-AAA subluxation patients as controls. All MR imaging was performed with supine neutral positioning. The morphology of the dens, bilateral facet joints, and surrounding ligaments, as well as the alignment of the anterior atlantoaxial joint, the spinolaminar line, and the intramedullary signal intensity, were assessed. This investigation statistically analyzed the difference among these groups.

RESULTS: Thirty-eight percent (15 of 40) of patients with AAA subluxation showed nAAA. There was no significant difference between the groups of AAA with normal and abnormal ADI except that more peridental pannus was seen in the latter group. More dens erosion ( P = .022), tilting of anterior atlantoaxial joint ( P = .022), peridental effusion ( P &lt; .001), lateral facet arthropathy ( P &lt; .001), abnormal spinolaminar line ( P = .001), and focal myelopathy ( P = .001) were observed in nAAA patients compared with the controls. The combination of peridental effusion, lateral facet arthropathy, abnormal intramedullary signals, and abnormal spinolaminar line showed a sensitivity of 100% and a specificity of 90% in diagnosing AAA subluxation.

CONCLUSIONS: MR imaging provides important biomechanical clues, other than ADI, that improve accuracy in diagnosing atlantoaxial instability.

AAA subluxation
:   anterior atlantoaxial subluxation
aAAA subluxation
:   anterior atlantoaxial subluxation with abnormal atlantodental interval
nAAA subluxation
:   anterior atlantoaxial subluxation with normal atlantodental interval
ADI
:   atlantodental interval
ALL
:   anterior longitudinal ligament
FSE
:   fast spin-echo
NS
:   not significant
PD
:   predental
RD
:   retrodental
SD
:   supradental
TM
:   tectorial membrane" />
<meta name="og-type" property="og:type" content="article" />
<meta name="og-image" property="og:image" content="http://ajnr-stage2.stage.highwire.org/sites/default/files/highwire/ajnr/31/5.cover.gif" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<link rel="alternate" type="application/vnd.ms-powerpoint" title="Powerpoint" href="/content/31/5/838.ppt" />
<link rel="alternate" type="text/plain" title="Full Text (Plain)" href="/content/31/5/838.full.txt" />
<link rel="alternate" type="application/pdf" title="Full Text (PDF)" href="/content/31/5/838.full.pdf" />
<link rel="canonical" href="http://ajnr-stage2.stage.highwire.org/content/31/5/838" />
<script>window.dataLayer = window.dataLayer || [];window.dataLayer.push({"page":{"hwTitle":"Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images","hwUrl":"http://ajnr-stage2.stage.highwire.org/content/31/5/838","hwPath":"/content/31/5/838.abstract","hwType":"journal page"},"user":{"hwMemberID":"","hwLoggedIntoInstitutionID":"","hwLoggedIntoInstitution":"","hwAccessUsageTerms":"guest","hwRegisteredUser":"no","hwHasFullTextAccess":"yes","hwEntitled":"no"},"content":{"hwIssueDate":"2010-05-01","hwIssueDateTime":"2010-05-01 00:00:00","hwPublicationDate":"2010-05-14","hwPublicationDateTime":"2010-05-14 08:02:12","hwNlmArticleType":"research-article","hwDOI":"10.3174/ajnr.A1941","hwAuthors":"S.-C. Hung,H.-M. Wu,W.-Y. Guo","hwContributors":"","hwIsEarlyRelease":"no","hwEissn":"1936-959X","hwPissn":"0195-6108","hwVolume":"31","hwIssue":"5","hwArticleType":"Spine","hwTabView":"main_tab","hwViewType":"abstract","hwAccessType":"Free","hwOpenAccess":"no","hwFreeAccess":"yes","hwTaxonomy":"","hwCorpusCode":"ajnr","hwType":"article","hwSubtitle":null,"hwOverline":null,"hwPisaId":"ajnr;31/5/838","hwFirstPage":"838","hwLastPage":"843","hwIsLatestVersion":"yes","hwIsCurrentIssue":"no","hwIsOpenIssue":"no","hwHasFullText":"yes","hwHasPDF":"yes","hwParentTitle":"American Journal of Neuroradiology: 31 (5)","hwElectronicPubDate":"2010-05-14","hwElectronicPubDateTime":"2010-05-14 08:02:12"}});
//--><!]]></script>
    <title>Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images | American Journal of Neuroradiology</title>  
    <link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__BJ6Ou6QsBRtnFTmxaakamOIS8n4QswDP2XnnZ1sxtaM__NBuvkP6eInGIkb1aJvUHx5PX79XApuxBDkk_77W5tYk__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__azeXjFYQUa4gTbdEg4sgM2osudOlAYwVv6vNmRXI3ac__zr83wx5lNxUVx-jSIFm8RDKOeMAB7RbaBxriFHS3dt4__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__Ep75tNOnm8H2Mejav16FnGCfM1sLwyporbQrCIgwg3g__vXGjszfa0bvxzymQ8Cfns-o2huFvm80jp3igN8XcYeI__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__TKi6DXKzgLPdEthh1Tnc63zY1QF4rLZHoM06Xy7VN6g__zaEHphFiBcrl8WVy_4n080y02dQ7HKxd_aqZbYgQ5Z0__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/all/modules/highwire/highwire/highwire.style.highwire.css?sycxuq" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__368m7sVtRu23rjqTxGZiVyTf_Vgj9GfVKn_6XVu-Ktw__awmYo-4mw13F7nmNUNtBYLumKanDZb8salegB2jkN90__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="//cdn.jsdelivr.net/qtip2/2.2.1/jquery.qtip.min.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__hdrV1jPSgxW0fPsRrK3sQAuhpElWcUo2f4JtkNIdb-Y__EwYsXwfG_cT9y3A9Cx4FsJxJRuF38Um_dApnuovtq68__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<style type="text/css" media="all">
/* <![CDATA[ */
#sliding-popup.sliding-popup-bottom,#sliding-popup.sliding-popup-bottom .eu-cookie-withdraw-banner,.eu-cookie-withdraw-tab{background:#000000;}#sliding-popup.sliding-popup-bottom.eu-cookie-withdraw-wrapper{background:transparent}#sliding-popup .popup-content #popup-text h1,#sliding-popup .popup-content #popup-text h2,#sliding-popup .popup-content #popup-text h3,#sliding-popup .popup-content #popup-text p,.eu-cookie-compliance-secondary-button,.eu-cookie-withdraw-tab{color:#ffffff !important;}.eu-cookie-withdraw-tab{border-color:#ffffff;}.eu-cookie-compliance-more-button{color:#ffffff !important;}

/* ]]> */
</style>

<!--[if lte IE 7]>
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__ElJr3PIJEvw3qLXc1cnYiLj2G4KgDPSXFOfm6Phf8hw__JdWGm15cDWjsK6KrFlQVXQix9YgNeYysf22XZHj-Y-c__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<![endif]-->
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__Wnlyen9qEpwh_Qaf9okEu4QdVGM0BDothxeqA6Nbvo8__EJmw6SZD9bYoS8jocCpPYS3JFRURpdzmuvJoAUNiI-g__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__nv7Hafs9UucfV8bmT4epWF4zWAFU2G9JLHVgOOHDqbA__k9QUw6MohZGXV0YlzqvUpPTbyzhbizsKOi4x3aA7Tx0__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />

<!--[if (lt IE 9)&(!IEMobile)]>
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__XH6bpcI0f2dImc-p674DLCZtWBGb-QwxJK1YexVGtno__vUceGprdo5nIhV6DH93X7fI3r8RcTJbChbas9TQXeW4__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<![endif]-->

<!--[if gte IE 9]><!-->
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__2WBMox6sOrN42ss5lCnH7WWVRdFdJCxtTKnQJYRwTE4__yqNvNYLvMpjy3ffuJrjjm9uW2i-Me1c23KLYuWHaqio__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
<!--<![endif]-->
<link type="text/css" rel="stylesheet" href="/sites/default/files/advagg_css/css__wxg7u6KrkAKrph8zjmzjNAiqxtVP2vhMWX2NZ6DPPZE__ECvRNuvDf2Tm_Pc-j1mEkt48QjmIz2s2CyWDspWAhhI__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.css" media="all" />
    <script type="text/javascript">
<!--//--><![CDATA[//><!--
/*!
 * yepnope1.5.4
 * (c) WTFPL, GPLv2
 */
(function(a,b,c){function d(a){return"[object Function]"==o.call(a)}function e(a){return"string"==typeof a}function f(){}function g(a){return!a||"loaded"==a||"complete"==a||"uninitialized"==a}function h(){var a=p.shift();q=1,a?a.t?m(function(){("c"==a.t?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){"img"!=a&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l=b.createElement(a),o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};1===y[c]&&(r=1,y[c]=[]),"object"==a?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),"img"!=a&&(r||2===y[c]?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i("c"==b?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),1==p.length&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&"[object Opera]"==o.call(a.opera),l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return"[object Array]"==o.call(a)},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,h){var i=b(a),j=i.autoCallback;i.url.split(".").pop().split("?").shift(),i.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]),i.instead?i.instead(a,e,f,g,h):(y[i.url]?i.noexec=!0:y[i.url]=1,f.load(i.url,i.forceCSS||!i.forceJS&&"css"==i.url.split(".").pop().split("?").shift()?"c":c,i.noexec,i.attrs,i.timeout),(d(e)||d(j))&&f.load(function(){k(),e&&e(i.origUrl,h,g),j&&j(i.origUrl,h,g),y[i.url]=2})))}function h(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var i,j,l=this.yepnope.loader;if(e(a))g(a,0,l,0);else if(w(a))for(i=0;i<a.length;i++)j=a[i],e(j)?g(j,0,l,0):w(j)?B(j):Object(j)===j&&h(j,l);else Object(a)===a&&h(a,l)},B.addPrefix=function(a,b){z[a]=b},B.addFilter=function(a){x.push(a)},B.errorTimeout=1e4,null==b.readyState&&b.addEventListener&&(b.readyState="loading",b.addEventListener("DOMContentLoaded",A=function(){b.removeEventListener("DOMContentLoaded",A,0),b.readyState="complete"},0)),a.yepnope=k(),a.yepnope.executeStack=h,a.yepnope.injectJs=function(a,c,d,e,i,j){var k=b.createElement("script"),l,o,e=e||B.errorTimeout;k.src=a;for(o in d)k.setAttribute(o,d[o]);c=j?h:c||f,k.onreadystatechange=k.onload=function(){!l&&g(k.readyState)&&(l=1,c(),k.onload=k.onreadystatechange=null)},m(function(){l||(l=1,c(1))},e),i?k.onload():n.parentNode.insertBefore(k,n)},a.yepnope.injectCss=function(a,c,d,e,g,i){var e=b.createElement("link"),j,c=i?h:c||f;e.href=a,e.rel="stylesheet",e.type="text/css";for(j in d)e.setAttribute(j,d[j]);g||(n.parentNode.insertBefore(e,n),m(c,0))}})(this,document);

//--><!]]>
</script>
<script type="text/javascript" src="/sites/all/libraries/modernizr/modernizr.min.js?sycxuq"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
yepnope({
  test: Modernizr.matchmedia,
  nope: '/sites/all/libraries/media-match/media.match.min.js'
});
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__wH8myWXKi4A-QKdUKDXzJAnGs-FRS1A2ZzTTNzjRAdI__4MCtOZK_Ov0QKyRlXNLGQ2LRlYRGWj9ArT-NpFox3QA__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
var googletag = googletag || {};
googletag.cmd = googletag.cmd || [];
googletag.slots = googletag.slots || {};
//--><!]]>
</script>
<script type="text/javascript" src="//securepubads.g.doubleclick.net/tag/js/gpt.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__9ici6QMeDS-cROq8R0RhuICsMGMP2wcJZNQQFsqQi44__kScSwG4RXGl1LXnj4qqt0ZxtNX4Gh2TK5W-o8Uup4SA__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__fwhbnUWIxW-jFl55E2mBYVtZTjGhJ1JWyZYAJ2cEd3A__jCrCuWCJIPYPe1FzZoUvsJWEjkNMmRIQHYek1h7idBE__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
googletag.slots["rhs"] = googletag.defineSlot("/446583111/RHS_300x250", [300, 250], "dfp-ad-rhs")
  .addService(googletag.pubads());
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__UR8BHznwml64Vq0ijSGFwlm-xe9ttj1aripHInFCOLw__irCalsu-H_fRTOPqjyCv1O8Ax7fqY6DDf-uMOV1dvGY__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
var mapping = googletag.sizeMapping()
  .addSize([768, 0], [728, 90])
  .addSize([0, 0], [300, 50])
  .build();
googletag.slots["bottom_leaderboard"] = googletag.defineSlot("/446583111/Bottom_Banner_728x90", [[728, 90], [300, 50]], "dfp-ad-bottom_leaderboard")
  .addService(googletag.pubads())
  .defineSizeMapping(mapping);
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__bQc6kyz_Gw2afC1F6wguCBh8Z8nev-hxX6F2Tw4bq6k__CO2faEsYCquY82rVj6as9HScSnogGHeR-oh5fSQydG0__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
var mapping = googletag.sizeMapping()
  .addSize([768, 0], [728, 90])
  .addSize([0, 0], [300, 50])
  .build();
googletag.slots["top_leaderboard"] = googletag.defineSlot("/446583111/Top_Leaderboard_728x90", [[728, 90], [300, 50]], "dfp-ad-top_leaderboard")
  .addService(googletag.pubads())
  .defineSizeMapping(mapping);
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__wS6WUeF11NLeJgCqxc-dMvjhALAMQG1jlaeWdG8yVZc__CPiombDS21ooaYdmqHXdcMoJwB2FMn18JzO97LewQxc__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
document.createElement( "picture" );
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__UK1ygaa8bCfT-jsjqYRdRLDZ5N17950T7K5WPC9XtpI__NqLYT1T1SMBsKukLWIe82VgCZYYCMHZX_f609-a1rj8__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
googletag.cmd.push(function() {
  googletag.pubads().enableAsyncRendering();
  googletag.pubads().enableSingleRequest();
  googletag.pubads().collapseEmptyDivs();
  googletag.pubads().addEventListener("slotRenderEnded", function (event) {
    if (event.isEmpty) {
      var id = event.slot.getSlotElementId();
      var x = document.getElementById(id);
      if (x.parentElement.classList.contains("dfp-tag-wrapper")) {
        x.parentElement.style.display = "none";
      }
    }
  });
  googletag.pubads().setTargeting("page:hwTitle", "Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images");
  googletag.pubads().setTargeting("page:hwUrl", "http://ajnr-stage2.stage.highwire.org/content/31/5/838");
  googletag.pubads().setTargeting("page:hwPath", "/content/31/5/838.abstract");
  googletag.pubads().setTargeting("page:hwType", "journal page");
  googletag.pubads().setTargeting("user:hwAccessUsageTerms", "guest");
  googletag.pubads().setTargeting("user:hwRegisteredUser", "no");
  googletag.pubads().setTargeting("user:hwHasFullTextAccess", "yes");
  googletag.pubads().setTargeting("user:hwEntitled", "no");
  googletag.pubads().setTargeting("content:hwIssueDate", "2010-05-01");
  googletag.pubads().setTargeting("content:hwIssueDateTime", "2010-05-01 00:00:00");
  googletag.pubads().setTargeting("content:hwPublicationDate", "2010-05-14");
  googletag.pubads().setTargeting("content:hwPublicationDateTime", "2010-05-14 08:02:12");
  googletag.pubads().setTargeting("content:hwNlmArticleType", "research-article");
  googletag.pubads().setTargeting("content:hwDOI", "10.3174/ajnr.A1941");
  googletag.pubads().setTargeting("content:hwAuthors", ["S.-C. Hung","H.-M. Wu","W.-Y. Guo"]);
  googletag.pubads().setTargeting("content:hwIsEarlyRelease", "no");
  googletag.pubads().setTargeting("content:hwEissn", "1936-959X");
  googletag.pubads().setTargeting("content:hwPissn", "0195-6108");
  googletag.pubads().setTargeting("content:hwVolume", "31");
  googletag.pubads().setTargeting("content:hwIssue", "5");
  googletag.pubads().setTargeting("content:hwArticleType", "Spine");
  googletag.pubads().setTargeting("content:hwTabView", "main_tab");
  googletag.pubads().setTargeting("content:hwViewType", "abstract");
  googletag.pubads().setTargeting("content:hwAccessType", "Free");
  googletag.pubads().setTargeting("content:hwOpenAccess", "no");
  googletag.pubads().setTargeting("content:hwFreeAccess", "yes");
  googletag.pubads().setTargeting("content:hwCorpusCode", "ajnr");
  googletag.pubads().setTargeting("content:hwType", "article");
  googletag.pubads().setTargeting("content:hwPisaId", "ajnr;31/5/838");
  googletag.pubads().setTargeting("content:hwFirstPage", "838");
  googletag.pubads().setTargeting("content:hwLastPage", "843");
  googletag.pubads().setTargeting("content:hwIsLatestVersion", "yes");
  googletag.pubads().setTargeting("content:hwIsCurrentIssue", "no");
  googletag.pubads().setTargeting("content:hwIsOpenIssue", "no");
  googletag.pubads().setTargeting("content:hwHasFullText", "yes");
  googletag.pubads().setTargeting("content:hwHasPDF", "yes");
  googletag.pubads().setTargeting("content:hwParentTitle", "American Journal of Neuroradiology: 31 (5)");
  googletag.pubads().setTargeting("content:hwElectronicPubDate", "2010-05-14");
  googletag.pubads().setTargeting("content:hwElectronicPubDateTime", "2010-05-14 08:02:12");
});

googletag.enableServices();
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__3vwOA0BwlnyBkt9H4CLg6FgNyKAh--OmfOxFOIu_5S4__EXTgktcHbQ7BQfelY6CnrqgPRc4i4eD6XcZ4i3xs5RU__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" async="async" src="https://scholar.google.com/scholar_js/casa.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__11OTRBANYp_FPYy8gxuWv8XYK780LivNl9ef5qg3rfw__TEVdNksA7-zrPiZwnenYHdToBjuVChsDlzQL_vP4NkY__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="//cdn.jsdelivr.net/qtip2/2.2.1/jquery.qtip.min.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__yiXGyyzC1oV2sZBtAUN2DFoM2mAH5KP0iYCqS1dmafE__UiTPqZo1iNHqhqhx1lKGu2xkUGpxmin5ny6_22C53JA__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
if(typeof window.MathJax === "undefined") window.MathJax = { menuSettings: { zoom: "Click" } };
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__gzglMimeshoybn5FdOUfx5zFIzXjSZCarAdAqdFwzb0__XnS2ZmP_Eu1FvGruois2GWaJM4qn-3H8Rt4VF8dvyrA__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="https://www.google.com/recaptcha/api.js?hl=en&amp;render=explicit&amp;onload=drupalRecaptchaOnload"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__4ykqVVdSaGtVGauctG3E3Uojp_237f35KQ7wMtKX9S4__4JHByHSitU6UdWxmWARTSoZyB2PFgzkw__raxGdvbvk__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--

      $(document).ready(function() {
          $.getJSON("//www.deepdyve.com/rental-link?docId=10.3174/ajnr.A1941&journal=1936-959X&fieldName=journal_doi&affiliateId=asnr&format=jsonp&callback=?", function(data) {
            if (data.status === "ok") {
              // Update the href url so it goes straight to the article page
              $(".js-deepdyve-link a").attr("href", data.url);
              $(".js-deepdyve-link").show();
            } else if (data.status === "not_found") {
              $(".js-deepdyve-link").hide();
            }
          });
        });
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__4lG8Nd_Z78ebRQwNtbOlh_jt-whQYFW5Try6DwQUwAM__8EEmyuTE_JxYCL1fbIkxkI5UUKYRtta33k484QkazhA__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" async="async" src="https://www.googletagmanager.com/gtag/js?id=G-4CRTLTY8KW"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
window.dataLayer = window.dataLayer || [];function gtag(){dataLayer.push(arguments)};gtag("js", new Date());gtag("set", "developer_id.dMDhkMT", true);gtag("config", "G-4CRTLTY8KW", {"groups":"default","anonymize_ip":true});
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__xwmR_XUqgIHdKocIkn2GiqYMVWJ0gY7OwpoARPRxEYM__CdSkXbn46iKUJfVct1nUx50N8MQ35eZOCMya9EuGbeU__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__156__G_TX0wWbp2x4EuISKOgbs4NaeHZ2KmXq85T6UI__w2izI_4UeJKq2XZJo79kNkQyxp_-2ptYjzA3YJcr-tg__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__az53Pz-SG0wejB-7UDzC-AbKqNFb4dAiZbq9Ymbj0sY__8FyXs8A34T1jX6OUXsgX27-4ASoy8QDncslXiOc2PK4__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
jQuery.extend(Drupal.settings, {"basePath":"\/","pathPrefix":"","ajaxPageState":{"theme":"jcore_1","theme_token":"v1wmpN4lY0OVtTA025BFK_wpmrcyneCL1FWwlYM3Yko","js":{"sites\/all\/libraries\/modernizr\/modernizr.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/jquery\/1.8\/jquery.min.js":1,"misc\/jquery-extend-3.4.0.js":1,"misc\/jquery.once.js":1,"misc\/drupal.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.core.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.widget.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.button.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.mouse.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.draggable.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.position.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.resizable.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.dialog.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.tooltip.min.js":1,"sites\/all\/modules\/contrib\/jquery_update\/replace\/ui\/ui\/minified\/jquery.ui.accordion.min.js":1,"sites\/all\/libraries\/jquery.bgiframe\/jquery.bgiframe.js":1,"sites\/all\/libraries\/jquery.hoverIntent\/jquery.hoverIntent.js":1,"sites\/all\/libraries\/superfish\/superfish.js":1,"sites\/all\/modules\/contrib\/nice_menus\/js\/nice_menus.js":1,"sites\/all\/modules\/contrib\/eu_cookie_compliance\/js\/jquery.cookie-1.4.1.min.js":1,"sites\/all\/modules\/highwire\/highwire\/js\/highwire.equal-heights.js":1,"sites\/all\/modules\/highwire\/highwire\/js\/highwire.panels-ajax-tab.js":1,"sites\/all\/libraries\/colorbox\/jquery.colorbox-min.js":1,"sites\/all\/modules\/contrib\/colorbox\/js\/colorbox.js":1,"sites\/all\/modules\/contrib\/colorbox\/styles\/default\/colorbox_style.js":1,"https:\/\/scholar.google.com\/scholar_js\/casa.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_log\/highwire_log.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_user\/js\/highwire_user_meta.js":1,"sites\/all\/modules\/contrib\/panels_ajax_tab\/js\/panels_ajax_tab.js":1,"\/\/cdn.jsdelivr.net\/qtip2\/2.2.1\/jquery.qtip.min.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_article_reference_popup.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_at_symbol.js":1,"sites\/all\/modules\/contrib\/captcha\/captcha.js":1,"misc\/textarea.js":1,"sites\/all\/modules\/contrib\/recaptcha\/js\/recaptcha.js":1,"https:\/\/www.google.com\/recaptcha\/api.js?hl=en\u0026render=explicit\u0026onload=drupalRecaptchaOnload":1,"sites\/all\/modules\/highwire\/highwire\/highwire_citation\/plugins\/content_types\/js\/highwire_citation_export.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/minipanel_dialog_link.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_share_dialog.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/clipboard.min.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_clipboard.js":1,"sites\/all\/modules\/contrib\/service_links\/js\/twitter_button.js":1,"sites\/all\/modules\/contrib\/service_links\/js\/facebook_like.js":1,"sites\/all\/modules\/contrib\/service_links\/js\/google_plus_one.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_article_nav.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_nav_float.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_citing_links.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_search\/plugins\/content_types\/js\/highwire_search_similar_articles.js":1,"sites\/all\/modules\/contrib\/panels_accordion\/js\/panels_accordion.js":1,"sites\/all\/modules\/highwire\/highwire\/js\/highwire.article-citation-access.js":1,"sites\/all\/modules\/highwire\/highwire\/js\/highwire.article-citation-author-tooltip.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_responsive\/plugins\/styles\/highwire_responsive_toggle\/highwire_responsive_toggle.js":1,"sites\/all\/modules\/contrib\/google_analytics\/googleanalytics.js":1,"https:\/\/www.googletagmanager.com\/gtag\/js?id=G-4CRTLTY8KW":1,"sites\/all\/themes\/highwire\/jcore_1\/js\/theme-scripts.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_responsive\/js\/highwire-mediaqueries.js":1,"sites\/all\/libraries\/enquire.js\/enquire.min.js":1,"sites\/all\/modules\/contrib\/picture\/picturefill2\/picturefill.min.js":1,"sites\/all\/modules\/contrib\/picture\/picture.min.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_panels_ajax_tab.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_openurl.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_google_scholar_sprinkle.js":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/js\/highwire_article_trendmd.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_user\/plugins\/content_types\/js\/highwire_user_salutation.js":1,"sites\/all\/modules\/contrib\/eu_cookie_compliance\/js\/eu_cookie_compliance.js":1,"http:\/\/securepubads.g.doubleclick.net\/tag\/js\/gpt.js":1,"sites\/all\/modules\/highwire\/highwire\/js\/highwire.gtranslate.js":1,"sites\/all\/modules\/highwire\/highwire\/highwire_datalayer\/js\/highwire_datalayer.js":1,"sites\/all\/themes\/contrib\/omega\/omega\/js\/jquery.formalize.js":1,"sites\/all\/themes\/contrib\/omega\/omega\/js\/omega-mediaqueries.js":1,"sites\/all\/themes\/contrib\/omega\/omega\/js\/omega-equalheights.js":1},"css":{"modules\/system\/system.base.css":1,"modules\/system\/system.menus.css":1,"modules\/system\/system.messages.css":1,"modules\/system\/system.theme.css":1,"misc\/ui\/jquery.ui.core.css":1,"misc\/ui\/jquery.ui.theme.css":1,"misc\/ui\/jquery.ui.button.css":1,"misc\/ui\/jquery.ui.resizable.css":1,"misc\/ui\/jquery.ui.dialog.css":1,"misc\/ui\/jquery.ui.tooltip.css":1,"misc\/ui\/jquery.ui.accordion.css":1,"sites\/all\/modules\/contrib\/date\/date_api\/date.css":1,"sites\/all\/modules\/contrib\/date\/date_popup\/themes\/datepicker.1.7.css":1,"modules\/field\/theme\/field.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_draw\/css\/highwire-draw.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_folders\/highwire_folders.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_responsive\/css\/highwire-responsive.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_saved_searches\/highwire_saved_searches.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_user\/highwire_user.css":1,"modules\/node\/node.css":1,"sites\/all\/modules\/contrib\/picture\/picture_wysiwyg.css":1,"modules\/search\/search.css":1,"modules\/user\/user.css":1,"sites\/all\/modules\/contrib\/views\/css\/views.css":1,"sites\/all\/modules\/contrib\/ckeditor\/css\/ckeditor.css":1,"sites\/all\/modules\/contrib\/colorbox\/styles\/default\/colorbox_style.css":1,"sites\/all\/modules\/contrib\/ctools\/css\/ctools.css":1,"sites\/all\/modules\/contrib\/google_admanager\/google_admanager.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire.style.highwire.css":1,"sites\/all\/modules\/highwire\/highwire\/css\/nlm-elements.css":1,"sites\/all\/modules\/contrib\/panels\/css\/panels.css":1,"public:\/\/ctools\/css\/263bfdb18936424f0ade19d6bd885f37.css":1,"sites\/all\/modules\/contrib\/panels_ajax_tab\/css\/panels_ajax_tab.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/css\/highwire_corrections.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire.style.markup.css":1,"\/\/cdn.jsdelivr.net\/qtip2\/2.2.1\/jquery.qtip.min.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/layouts\/highwire_2col_stacked\/highwire-2col-stacked.css":1,"sites\/all\/modules\/contrib\/forward\/forward.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/css\/highwire_share_link.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/css\/highwire_copy_permalink.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/css\/highwire_citing_links.css":1,"sites\/all\/modules\/highwire\/highwire\/plugins\/content_types\/css\/highwire_reports_feed.css":1,"sites\/all\/modules\/highwire\/highwire\/css\/highwire-article-citation-list.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_responsive\/plugins\/styles\/highwire_responsive_toggle\/highwire_responsive_toggle.css.less":1,"sites\/all\/modules\/contrib\/nice_menus\/css\/nice_menus.css":1,"sites\/all\/modules\/contrib\/nice_menus\/css\/nice_menus_default.css":1,"sites\/all\/modules\/contrib\/panels\/plugins\/layouts\/onecol\/onecol.css":1,"sites\/all\/modules\/contrib\/eu_cookie_compliance\/css\/eu_cookie_compliance.css":1,"sites\/all\/modules\/highwire\/highwire\/css\/highwire.gtranslate.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_theme_tools\/css\/font-hwicons.css":1,"sites\/all\/modules\/highwire\/highwire\/highwire_theme_tools\/css\/font-hwicons-glyphs.css":1,"sites\/all\/themes\/highwire\/jcore_1\/eu_cookie_compliance.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/font-awesome-ie7.css":1,"sites\/all\/themes\/contrib\/omega\/alpha\/css\/alpha-reset.css":1,"sites\/all\/themes\/contrib\/omega\/alpha\/css\/alpha-mobile.css":1,"sites\/all\/themes\/contrib\/omega\/alpha\/css\/alpha-alpha.css":1,"sites\/all\/themes\/contrib\/omega\/omega\/css\/formalize.css":1,"sites\/all\/themes\/contrib\/omega\/omega\/css\/omega-text.css":1,"sites\/all\/themes\/contrib\/omega\/omega\/css\/omega-branding.css":1,"sites\/all\/themes\/contrib\/omega\/omega\/css\/omega-menu.css":1,"sites\/all\/themes\/contrib\/omega\/omega\/css\/omega-forms.css":1,"sites\/all\/modules\/highwire\/highwire\/css\/highwire-forms.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/mobile-reset.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/font-awesome.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/forms.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/global.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/jquery-ui-elements.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/text.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/eletters.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/colors.css.less":1,"ie::normal::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default.css":1,"ie::normal::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default-normal.css":1,"ie::normal::sites\/all\/themes\/highwire\/jcore_1\/css\/grid\/jcore_default\/normal\/jcore-default-normal-30.css":1,"narrow::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default.css":1,"narrow::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default-narrow.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/grid\/jcore_default\/narrow\/jcore-default-narrow-30.css":1,"normal::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default.css":1,"normal::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default-normal.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/grid\/jcore_default\/normal\/jcore-default-normal-30.css":1,"wide::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default.css":1,"wide::sites\/all\/themes\/highwire\/jcore_1\/css\/jcore-1-jcore-default-wide.css":1,"sites\/all\/themes\/highwire\/jcore_1\/css\/grid\/jcore_default\/wide\/jcore-default-wide-30.css":1,"sites\/all\/modules\/shared\/jnl_ajnr_styles\/css\/jnl-ajnr-styles.css.less":1,"sites\/all\/modules\/shared\/jnl_ajnr_styles\/css\/jnl-ajnr-breakpoints.css.less":1}},"colorbox":{"opacity":"0.85","current":"{current} of {total}","previous":"\u00ab Prev","next":"Next \u00bb","close":"Close","maxWidth":"98%","maxHeight":"98%","fixed":true,"mobiledetect":true,"mobiledevicewidth":"480px"},"highwire":{"markup":[{"requested":"short-text","variant":"abstract","view":"abstract","pisa":"ajnr;31\/5\/838"},{"requested":"short-text","variant":"abstract","view":"abstract","pisa":"ajnr;31\/5\/838"},{"requested":"abstract","variant":"abstract","view":"abstract","pisa":"ajnr;31\/5\/838"},{"requested":"full-text","variant":"full-text","view":"full","pisa":"ajnr;31\/5\/838"}],"nid":"9880","apath":"\/ajnr\/31\/5\/838.atom","pisa":"ajnr;31\/5\/838","ac":{"\/ajnr\/31\/5\/838.atom":{"access":{"full":true,"reprint":true,"abstract":true},"pisa_id":"","apath":"\/ajnr\/31\/5\/838.atom","jcode":"ajnr"},"ajnr;31\/5\/838":{"access":{"full":true},"pisa_id":"ajnr;31\/5\/838","apath":"","jcode":"ajnr"}},"processed":["highwire_math"],"trendmd":{"trendmd-suggestions":"{\u0022element\u0022:\u0022#trendmd-suggestions\u0022,\u0022track_id\u0022:\u0022null\u0022}"},"modal_window_width":"560","share_modal_width":"560","share_modal_title":"Share this Article","dataLayer":"{\u0022page\u0022:{\u0022hwTitle\u0022:\u0022Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images\u0022,\u0022hwUrl\u0022:\u0022http:\\\/\\\/ajnr-stage2.stage.highwire.org\\\/content\\\/31\\\/5\\\/838\u0022,\u0022hwPath\u0022:\u0022\\\/content\\\/31\\\/5\\\/838.abstract\u0022,\u0022hwType\u0022:\u0022journal page\u0022},\u0022user\u0022:{\u0022hwMemberID\u0022:\u0022\u0022,\u0022hwLoggedIntoInstitutionID\u0022:\u0022\u0022,\u0022hwLoggedIntoInstitution\u0022:\u0022\u0022,\u0022hwAccessUsageTerms\u0022:\u0022guest\u0022,\u0022hwRegisteredUser\u0022:\u0022no\u0022,\u0022hwHasFullTextAccess\u0022:\u0022yes\u0022,\u0022hwEntitled\u0022:\u0022no\u0022},\u0022content\u0022:{\u0022hwIssueDate\u0022:\u00222010-05-01\u0022,\u0022hwIssueDateTime\u0022:\u00222010-05-01 00:00:00\u0022,\u0022hwPublicationDate\u0022:\u00222010-05-14\u0022,\u0022hwPublicationDateTime\u0022:\u00222010-05-14 08:02:12\u0022,\u0022hwNlmArticleType\u0022:\u0022research-article\u0022,\u0022hwDOI\u0022:\u002210.3174\\\/ajnr.A1941\u0022,\u0022hwAuthors\u0022:\u0022S.-C. Hung,H.-M. Wu,W.-Y. Guo\u0022,\u0022hwContributors\u0022:\u0022\u0022,\u0022hwIsEarlyRelease\u0022:\u0022no\u0022,\u0022hwEissn\u0022:\u00221936-959X\u0022,\u0022hwPissn\u0022:\u00220195-6108\u0022,\u0022hwVolume\u0022:\u002231\u0022,\u0022hwIssue\u0022:\u00225\u0022,\u0022hwArticleType\u0022:\u0022Spine\u0022,\u0022hwTabView\u0022:\u0022main_tab\u0022,\u0022hwViewType\u0022:\u0022abstract\u0022,\u0022hwAccessType\u0022:\u0022Free\u0022,\u0022hwOpenAccess\u0022:\u0022no\u0022,\u0022hwFreeAccess\u0022:\u0022yes\u0022,\u0022hwTaxonomy\u0022:\u0022\u0022,\u0022hwCorpusCode\u0022:\u0022ajnr\u0022,\u0022hwType\u0022:\u0022article\u0022,\u0022hwSubtitle\u0022:null,\u0022hwOverline\u0022:null,\u0022hwPisaId\u0022:\u0022ajnr;31\\\/5\\\/838\u0022,\u0022hwFirstPage\u0022:\u0022838\u0022,\u0022hwLastPage\u0022:\u0022843\u0022,\u0022hwIsLatestVersion\u0022:\u0022yes\u0022,\u0022hwIsCurrentIssue\u0022:\u0022no\u0022,\u0022hwIsOpenIssue\u0022:\u0022no\u0022,\u0022hwHasFullText\u0022:\u0022yes\u0022,\u0022hwHasPDF\u0022:\u0022yes\u0022,\u0022hwParentTitle\u0022:\u0022American Journal of Neuroradiology: 31 (5)\u0022,\u0022hwElectronicPubDate\u0022:\u00222010-05-14\u0022,\u0022hwElectronicPubDateTime\u0022:\u00222010-05-14 08:02:12\u0022}}"},"highwire_panel_tabs":[{"panel_name":"jnl_ajnr_tab_pdf","panel_ajax_tab":"jnl_ajnr_tab_pdf"}],"panel_ajax_tab":{"path":"sites\/all\/modules\/contrib\/panels_ajax_tab"},"instances":"{\u0022highwire_abstract_tooltip\u0022:{\u0022content\u0022:{\u0022text\u0022:\u0022\u0022},\u0022style\u0022:{\u0022tip\u0022:{\u0022width\u0022:20,\u0022height\u0022:20,\u0022border\u0022:1,\u0022offset\u0022:0,\u0022corner\u0022:true},\u0022classes\u0022:\u0022qtip-custom hw-tooltip hw-abstract-tooltip qtip-shadow qtip-rounded\u0022,\u0022classes_custom\u0022:\u0022hw-tooltip hw-abstract-tooltip\u0022},\u0022position\u0022:{\u0022at\u0022:\u0022right center\u0022,\u0022my\u0022:\u0022left center\u0022,\u0022viewport\u0022:true,\u0022adjust\u0022:{\u0022method\u0022:\u0022shift\u0022}},\u0022show\u0022:{\u0022event\u0022:\u0022mouseenter click \u0022,\u0022solo\u0022:true},\u0022hide\u0022:{\u0022event\u0022:\u0022mouseleave \u0022,\u0022fixed\u0022:1,\u0022delay\u0022:\u0022100\u0022}},\u0022highwire_author_tooltip\u0022:{\u0022content\u0022:{\u0022text\u0022:\u0022\u0022},\u0022style\u0022:{\u0022tip\u0022:{\u0022width\u0022:15,\u0022height\u0022:15,\u0022border\u0022:1,\u0022offset\u0022:0,\u0022corner\u0022:true},\u0022classes\u0022:\u0022qtip-custom hw-tooltip hw-author-tooltip qtip-shadow qtip-rounded\u0022,\u0022classes_custom\u0022:\u0022hw-tooltip hw-author-tooltip\u0022},\u0022position\u0022:{\u0022at\u0022:\u0022top center\u0022,\u0022my\u0022:\u0022bottom center\u0022,\u0022viewport\u0022:true,\u0022adjust\u0022:{\u0022method\u0022:\u0022\u0022}},\u0022show\u0022:{\u0022event\u0022:\u0022mouseenter \u0022,\u0022solo\u0022:true},\u0022hide\u0022:{\u0022event\u0022:\u0022mouseleave \u0022,\u0022fixed\u0022:1,\u0022delay\u0022:\u0022100\u0022}},\u0022highwire_reflinks_tooltip\u0022:{\u0022content\u0022:{\u0022text\u0022:\u0022\u0022},\u0022style\u0022:{\u0022tip\u0022:{\u0022width\u0022:15,\u0022height\u0022:15,\u0022border\u0022:1,\u0022mimic\u0022:\u0022top center\u0022,\u0022offset\u0022:0,\u0022corner\u0022:true},\u0022classes\u0022:\u0022qtip-custom hw-tooltip hw-ref-link-tooltip qtip-shadow qtip-rounded\u0022,\u0022classes_custom\u0022:\u0022hw-tooltip hw-ref-link-tooltip\u0022},\u0022position\u0022:{\u0022at\u0022:\u0022bottom left\u0022,\u0022my\u0022:\u0022top left\u0022,\u0022viewport\u0022:true,\u0022adjust\u0022:{\u0022method\u0022:\u0022flip\u0022}},\u0022show\u0022:{\u0022event\u0022:\u0022mouseenter \u0022,\u0022solo\u0022:true},\u0022hide\u0022:{\u0022event\u0022:\u0022mouseleave \u0022,\u0022fixed\u0022:1,\u0022delay\u0022:\u0022100\u0022}}}","qtipDebug":"{\u0022leaveElement\u0022:0}","urlIsAjaxTrusted":{"\/content\/31\/5\/838.abstract":true},"ws_fl":{"width":100,"height":21},"ws_gpo":{"size":"","annotation":"","lang":"","callback":"","width":300},"highwire_search_similar_articles":{"highwire-search-similar-articles-list-1":{"conf":{"context":"requiredcontext_entity:node_1","override_title":1,"override_title_text":"\u003Ci class=\u0022icon-caret-right\u0022\u003E\u003C\/i\u003E Similar Articles","number_per_page":"5","show_pager":0,"more_link_path":"similar\/articles","more_link":1,"empty_message":"No similar articles are available.","citation_style":"jcore_standard","title_type":"prefer_short","title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","display_original_link":0,"display_access_indicator":0,"display_cme_link":0,"display_access_indicator_text":0,"display_highlight_image":"0","display_variants":0,"display_supplements":0,"display_abstract_tooltip":0,"display_author_tooltip":0,"override_title_heading":"h2","citation_settings_source":"citation_manager","citation_manager_wrapper":{"citation_manager_citation":"jcore_list_title_only"},"corpus_config_wrapper":{"corpus_config_citation_context":[]},"cache_enabled":1,"cache_time":"600","short_title_options":{"char_count":"50","add_ellipsis":0},"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"highlight_image_style":"","featured_image_variant":"large","featured_image_click_image":"colorbox","display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":1,"display_orcid_tooltip":0,"display_ads_search_tooltip":0,"display_agricola_tooltip":0,"author_site_search_path":"","display_translations":0,"display_translations_text":"","display_translations_text_icon":"","bundle_overrides_checkboxes":{"highwire_book_fragment":{"selector":0},"highwire_news_story":{"selector":0},"highwire_book_edition":{"selector":0},"highwire_article":{"selector":0},"highwire_issue":{"selector":0},"highwire_comment":{"selector":0},"highwire_fragment":{"selector":0},"highwire_book_section":{"selector":0},"highwire_journal":{"selector":0}},"bundle_overrides":{"highwire_book_fragment":{"selector":0,"citation_style":"jcore_title_and_author","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":"0","access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"thumbnail","display_fragment_caption":1,"display_parent_citation":1,"parent_citation_type":"highwire_book_section","parent_citation_settings":{"citation_style":"folio_book_sections_standard","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","display_abstract_tooltip":0,"display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":0,"author_site_search_path":"search\/"}},"highwire_news_story":{"selector":0,"citation_style":"mla","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":"0","highlight_image_style":"","featured_image_click_image":"nothing","display_author_tooltip":0,"display_google_scholar_tooltip":0,"display_pubmed_tooltip":0,"display_advanced_search_tooltip":0},"highwire_book_edition":{"selector":0,"citation_style":"folio_books_standard","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":1,"display_orcid_tooltip":1,"author_site_search_path":"search\/"},"highwire_article":{"selector":0,"citation_style":"mla","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":0,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":"0","highlight_image_style":"","featured_image_variant":"large","featured_image_click_image":"nothing","display_cme_link":0,"display_abstract_tooltip":0,"display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":1,"display_orcid_tooltip":1,"display_ads_search_tooltip":0,"display_agricola_tooltip":0,"author_site_search_path":"search\/","display_translations":0,"display_translations_text":"Translations Available","display_translations_text_icon":"icon-globe"},"highwire_issue":{"selector":0,"citation_style":"mla","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","featured_image_click_image":"nothing","display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":0,"display_orcid_tooltip":1,"author_site_search_path":"search\/"},"highwire_comment":{"selector":0,"citation_style":"highwire_comment","show_title":0,"title_as_link":0,"title_as_link_type":"tab_view","author_format_type":"fullname","author_format_custom":"","author_list_separator":", ","date_format":"(j F Y)","display_comment_body":1,"display_attachment":1,"display_conflict_of_interest":1},"highwire_fragment":{"selector":0,"citation_style":"jcore_title_and_author","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":"0","access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","display_fragment_caption":1,"fragment_image_settings":{"fragment_image_variant":"medium","fragment_click_image":"colorbox","show_download_links":1},"display_parent_citation":1,"parent_citation_type":"highwire_article","parent_citation_settings":{"citation_style":"mla","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":0,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":"0","highlight_image_style":"","featured_image_variant":"large","featured_image_click_image":"nothing","display_cme_link":0,"display_abstract_tooltip":0,"display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":1,"display_orcid_tooltip":1,"display_ads_search_tooltip":0,"display_agricola_tooltip":0,"author_site_search_path":"search\/","display_translations":0,"display_translations_text":"Translations Available","display_translations_text_icon":"icon-globe"}},"highwire_book_section":{"selector":0,"citation_style":"folio_book_sections_standard","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","display_abstract_tooltip":0,"display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":0,"author_site_search_path":"search\/"},"highwire_journal":{"selector":0,"citation_style":"mla","cache_enabled":1,"cache_time":"600","title_type":"full","short_title_options":{"char_count":"50","add_ellipsis":0},"title_as_link":0,"display_subtitle":0,"choose_pubdate":"ppubdate","display_markup_snippet":"","highlight_image_toggle":0,"display_original_link":0,"display_access_indicator":0,"access_indicator_settings":{"open_access":{"icon":"icon-unlock","title":"Open Access"},"user_access":{"icon":"icon-ok-sign","title":"You have access"},"no_access":{"icon":"icon-lock","title":"Restricted access"}},"display_variants":0,"display_supplements":0,"pdf_download":{"display_pdf_download":0,"pdf_download_icon":"icon-cloud-download","pdf_download_text":"PDF"},"include_on_behalf":1,"cpath_prefix":"\/content","show_mark_citation":0,"display_infotrieve_link":0,"infotrieve_link_settings":{"icon":"icon-usd","link_caption":"Order full text via Infotrieve"},"display_highlight_image":0,"highlight_image_style":"","display_author_tooltip":0,"display_google_scholar_tooltip":1,"display_pubmed_tooltip":1,"display_advanced_search_tooltip":1,"display_author_landing_page_tooltip":0,"display_orcid_tooltip":1,"author_site_search_path":"search\/"}},"cpath_prefix":"\/content","ajax_loading_icon_classes":"icon-spinner icon-spin icon-2x","ajax_loading_text":"","highlight_image_toggle":0,"more_link_label":"See more","url_parameters":{"q":"node\/9880","variant":"abstract"}},"nid":"9880"}},"panels_accordion":{"highwire_article_accordion_container":{"heightStyle":"content","autoHeight":false,"collapsible":0,"region_accordion_id":"highwire_article_accordion_container","active":0,"animated":"slide"}},"color":{"logo":"http:\/\/ajnr-stage2.stage.highwire.org\/sites\/default\/files\/ajnr-web-logo_0.png"},"nice_menus_options":{"delay":800,"speed":"fast"},"highwireResponsive":{"enquire_enabled":1,"breakpoints_configured":1,"breakpoints":{"zero":"all and (min-width: 0px)","xsmall":"all and (min-width: 380px)","narrow":"all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)","normal":"all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)","wide":"all and (min-width: 1220px)"}},"eu_cookie_compliance":{"popup_enabled":1,"popup_agreed_enabled":0,"popup_hide_agreed":false,"popup_clicking_confirmation":true,"popup_scrolling_confirmation":false,"popup_html_info":"\u003Cdiv\u003E\n  \u003Cdiv class=\u0022popup-content info\u0022\u003E\n    \u003Cdiv id=\u0022popup-text\u0022\u003E\n      \u003Cp\u003EWe use cookies on this site to enhance your user experience. By clicking any link on this page you are giving your consent for us to set cookies.\u003C\/p\u003E\n    \u003C\/div\u003E\n    \u003Cdiv id=\u0022popup-buttons\u0022\u003E\n      \u003Cbutton type=\u0022button\u0022 role=\u0022dialog\u0022 aria-labelledby=\u0022Continue\u0022\n        class=\u0022agree-button eu-cookie-compliance-default-button\u0022\u003EContinue\u003C\/button\u003E\n                  \u003Cbutton type=\u0022button\u0022 role=\u0022dialog\u0022 aria-labelledby=\u0022Find out more\u0022\n        class=\u0022find-more-button eu-cookie-compliance-more-button\u0022\u003EFind out more\u003C\/button\u003E\n          \u003C\/div\u003E\n  \u003C\/div\u003E\n\u003C\/div\u003E","use_mobile_message":false,"mobile_popup_html_info":"\u003Cdiv\u003E\n  \u003Cdiv class=\u0022popup-content info\u0022\u003E\n    \u003Cdiv id=\u0022popup-text\u0022\u003E\n          \u003C\/div\u003E\n    \u003Cdiv id=\u0022popup-buttons\u0022\u003E\n      \u003Cbutton type=\u0022button\u0022 role=\u0022dialog\u0022 aria-labelledby=\u0022Continue\u0022\n        class=\u0022agree-button eu-cookie-compliance-default-button\u0022\u003EContinue\u003C\/button\u003E\n                  \u003Cbutton type=\u0022button\u0022 role=\u0022dialog\u0022 aria-labelledby=\u0022Find out more\u0022\n        class=\u0022find-more-button eu-cookie-compliance-more-button\u0022\u003EFind out more\u003C\/button\u003E\n          \u003C\/div\u003E\n  \u003C\/div\u003E\n\u003C\/div\u003E","mobile_breakpoint":"768","popup_html_agreed":"\u003Cdiv\u003E\n  \u003Cdiv class=\u0022popup-content agreed\u0022\u003E\n    \u003Cdiv id=\u0022popup-text\u0022\u003E\n      \u003Cp\u003EThank you for accepting cookies. You can now hide this message or find out more about cookies.\u003C\/p\u003E\n    \u003C\/div\u003E\n    \u003Cdiv id=\u0022popup-buttons\u0022\u003E\n      \u003Cbutton type=\u0022button\u0022 class=\u0022hide-popup-button eu-cookie-compliance-hide-button\u0022\u003EHide\u003C\/button\u003E\n              \u003Cbutton type=\u0022button\u0022 class=\u0022find-more-button eu-cookie-compliance-more-button-thank-you\u0022 \u003EFind out more\u003C\/button\u003E\n          \u003C\/div\u003E\n  \u003C\/div\u003E\n\u003C\/div\u003E","popup_use_bare_css":false,"popup_height":"auto","popup_width":"100%","popup_delay":1000,"popup_link":"\/help\/cookie-policy","popup_link_new_window":1,"popup_position":null,"popup_language":"en","store_consent":false,"better_support_for_screen_readers":0,"reload_page":0,"domain":"","popup_eu_only_js":0,"cookie_lifetime":365,"cookie_session":false,"disagree_do_not_show_popup":0,"method":"default","whitelisted_cookies":"","withdraw_markup":"\u003Cbutton type=\u0022button\u0022 class=\u0022eu-cookie-withdraw-tab\u0022\u003EPrivacy settings\u003C\/button\u003E\n\u003Cdiv class=\u0022eu-cookie-withdraw-banner\u0022\u003E\n  \u003Cdiv class=\u0022popup-content info\u0022\u003E\n    \u003Cdiv id=\u0022popup-text\u0022\u003E\n      \u003Cp\u003E\u0026lt;h2\u0026gt;We use cookies on this site to enhance your user experience\u0026lt;\/h2\u0026gt;\u0026lt;p\u0026gt;You have given your consent for us to set cookies.\u0026lt;\/p\u0026gt;\u003C\/p\u003E\n    \u003C\/div\u003E\n    \u003Cdiv id=\u0022popup-buttons\u0022\u003E\n      \u003Cbutton type=\u0022button\u0022 class=\u0022eu-cookie-withdraw-button\u0022\u003EWithdraw consent\u003C\/button\u003E\n    \u003C\/div\u003E\n  \u003C\/div\u003E\n\u003C\/div\u003E\n","withdraw_enabled":false},"googleanalytics":{"account":["G-4CRTLTY8KW"],"trackOutbound":1,"trackMailto":1,"trackDownload":1,"trackDownloadExtensions":"7z|aac|arc|arj|asf|asx|avi|bin|csv|doc(x|m)?|dot(x|m)?|exe|flv|gif|gz|gzip|hqx|jar|jpe?g|js|mp(2|3|4|e?g)|mov(ie)?|msi|msp|pdf|phps|png|ppt(x|m)?|pot(x|m)?|pps(x|m)?|ppam|sld(x|m)?|thmx|qtm?|ra(m|r)?|sea|sit|tar|tgz|torrent|txt|wav|wma|wmv|wpd|xls(x|m|b)?|xlt(x|m)|xlam|xml|z|zip","trackColorbox":1},"omega":{"layouts":{"primary":"normal","order":["narrow","normal","wide"],"queries":{"narrow":"all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)","normal":"all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)","wide":"all and (min-width: 1220px)"}}}});
//--><!]]>
</script>
    <!--[if lt IE 9]><script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
  </head>
  <body class="html not-front not-logged-in page-node page-node- page-node-9880 node-type-highwire-article context-content hw-default-jcode-ajnr hw-article-type-research-article hw-article-category-spine">
<!-- Google Tag Manager -->
<noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-MXP45WNH" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<script type="text/javascript">(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0];var j=d.createElement(s);var dl=l!='dataLayer'?'&l='+l:'';j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;j.type='text/javascript';j.async=true;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-MXP45WNH');</script>
<!-- End Google Tag Manager -->
    <div id="skip-link">
      <a href="#main-content" class="element-invisible element-focusable">Skip to main content</a>
    </div>
    <div class="region region-page-top" id="region-page-top">
  <div class="region-inner region-page-top-inner">
      </div>
</div>    <div class="page clearfix footer-borders panels-page panels-layout-jcore_2col" id="page">
      <header id="section-header" class="section section-header">
  <div id="zone-advertising-top-wrapper" class="zone-wrapper zone-advertising-top-wrapper clearfix">  
  <div id="zone-advertising-top" class="zone zone-advertising-top clearfix container-30">
    <div class="grid-28 suffix-1 prefix-1 region region-ad-top" id="region-ad-top">
  <div class="region-inner region-ad-top-inner">
    <div class="block block-panels-mini mobile-hiddens rtecenter block-jnl-ajnr-ad-leaderboard block-panels-mini-jnl-ajnr-ad-leaderboard odd block-without-title" id="block-panels-mini-jnl-ajnr-ad-leaderboard">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_ad_leaderboard">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-dfp-pane text-center" >
  
      
  
  <div class="pane-content">
    <div id="dfp-ad-top_leaderboard-wrapper" class="dfp-tag-wrapper">
<div class="slug">Advertisement</div>
<div  id="dfp-ad-top_leaderboard" class="dfp-tag-wrapper">
  <script type="text/javascript">
    googletag.cmd.push(function() {
      googletag.display("dfp-ad-top_leaderboard");
    });
  </script>
</div>
</div>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>  </div>
</div>  </div>
</div><div id="zone-superheader-wrapper" class="zone-wrapper zone-superheader-wrapper clearfix mobile-only print-hidden">  
  <div id="zone-superheader" class="zone zone-superheader clearfix mobile-only print-hidden container-30">
    <div class="grid-30 region region-superheader" id="region-superheader">
  <div class="region-inner region-superheader-inner">
    <div class="block block-panels-mini block-responsive-menu block-panels-mini-responsive-menu odd block-without-title" id="block-panels-mini-responsive-menu">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-responsive_menu">
  <div class="panel-panel panel-col">
    <div><div id="unique-id3" class="highwire-responsive-toggle-group"><div class="panel-pane pane-panels-mini pane-responsive-menu-main-menu" >
  
        <h2 class="pane-title"><span class="icon-reorder"></span><span class="element-invisible">Main menu</span></h2>
    
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-responsive_menu_main_menu">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-menu-tree pane-main-menu" >
  
      
  
  <div class="pane-content">
    <div class="menu-block-wrapper menu-block-ctools-main-menu-1 menu-name-main-menu parent-mlid-main-menu:0 menu-level-1">
  <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-772" role="menuitem"><a href="/" class="" data-icon-position="" data-hide-link-title="0">Home</a></li>
<li class="expanded active-trail menu-mlid-773" role="menuitem"><a href="/content/current" data-hide-link-title="0" class="active active-trail" data-icon-position="">Content</a><nav class="menubar-nav"><ul class="menu" role="menu"><li class="first expanded menu-mlid-774" role="menuitem"><a href="/content/current" data-hide-link-title="0" class="" data-icon-position="">Current Issue</a></li>
<li class="leaf menu-mlid-1747" role="menuitem"><a href="/content/early/preprint" data-hide-link-title="0" class="" data-icon-position="">Publication Preview--Preprint</a></li>
<li class="leaf menu-mlid-775" role="menuitem"><a href="/content/early/recent" data-hide-link-title="0" class="" data-icon-position="">Publication Preview--Ahead of Print</a></li>
<li class="leaf menu-mlid-776" role="menuitem"><a href="/content/by/year" data-hide-link-title="0" class="" data-icon-position="">Past Issue Archive</a></li>
<li class="leaf menu-mlid-900" role="menuitem"><a href="/cow/by/year" data-hide-link-title="0" class="" data-icon-position="">Case of the Week Archive</a></li>
<li class="leaf menu-mlid-1006" role="menuitem"><a href="/cc/by/year" data-hide-link-title="0" class="" data-icon-position="">Classic Case Archive</a></li>
<li class="leaf menu-mlid-901" role="menuitem"><a href="/com/by/year" data-hide-link-title="0" class="" data-icon-position="">Case of the Month Archive</a></li>
<li class="last leaf menu-mlid-1334" role="menuitem"><a href="http://www.ajnr.org/content/covid-19-content-and-resources" data-hide-link-title="0" class="" data-icon-position="">COVID-19 Content and Resources</a></li>
</ul></nav></li>
<li class="expanded menu-mlid-784" role="menuitem"><a href="/content/about-us" class="" data-icon-position="" data-hide-link-title="0">About Us</a><nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-785" role="menuitem"><a href="/page/content/About" data-hide-link-title="0" class="" data-icon-position="">About AJNR</a></li>
<li class="leaf menu-mlid-899" role="menuitem"><a href="https://www.ajnr.org/page/content/Ed-Board" data-hide-link-title="0" class="" data-icon-position="">Editorial Board</a></li>
<li class="last leaf menu-mlid-864" role="menuitem"><a href="http://www.asnr.org" data-hide-link-title="0" target="_blank" class="" data-icon-position="">American Society of Neuroradiology</a></li>
</ul></nav></li>
<li class="expanded menu-mlid-1746" role="menuitem"><a href="/" class="" data-icon-position="" data-hide-link-title="0">For Authors</a><nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-1725" role="menuitem"><a href="https://www.ajnr.org/content/author-policies" data-hide-link-title="0" class="" data-icon-position="">Author Policies</a></li>
<li class="leaf menu-mlid-1856" role="menuitem"><a href="https://www.ajnr.org/preprint_publishing" data-hide-link-title="0" class="" data-icon-position="">Preprint Publishing</a></li>
<li class="last leaf menu-mlid-1726" role="menuitem"><a href="https://www.ajnr.org/content/manuscript-submission-guidelines" data-hide-link-title="0" class="" data-icon-position="">Manuscript Submission Guidelines</a></li>
</ul></nav></li>
<li class="leaf menu-mlid-862" role="menuitem"><a href="https://mc.manuscriptcentral.com/ajnr" data-hide-link-title="0" target="_blank" class="" data-icon-position="">Submit a Manuscript</a></li>
<li class="expanded menu-mlid-1184" role="menuitem"><a href="/content/about-us" data-hide-link-title="0" class="" data-icon-position="">Special Collections</a><nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-1733" role="menuitem"><a href="http://www.ajnr.org/cc/CSF-Spinal-Leak" data-hide-link-title="0" class="" data-icon-position="">Spinal CSF Leak Articles (Jan 2020-June 2024)</a></li>
<li class="leaf menu-mlid-1185" role="menuitem"><a href="http://www.ajnr.org/cc/most-impactful-ajnr-articles" data-hide-link-title="0" class="" data-icon-position="">Most Impactful AJNR Articles</a></li>
<li class="last leaf menu-mlid-1896" role="menuitem"><a href="http://www.ajnr.org/cc/2024-Awards" data-hide-link-title="0" class="" data-icon-position="">2024 AJNR Journal Awards</a></li>
</ul></nav></li>
<li class="last expanded menu-mlid-788" role="menuitem"><a href="/content/advertising" class="" data-icon-position="" data-hide-link-title="0">More</a><nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-780" role="menuitem"><a href="/content/subscriber-help-and-services" data-hide-link-title="0" class="" data-icon-position="">Subscribers</a></li>
<li class="leaf menu-mlid-863" role="menuitem"><a href="https://marketplace.copyright.com/rs-ui-web/mp/details/journal/122810747" data-hide-link-title="0" class="" data-icon-position="">Permissions</a></li>
<li class="leaf menu-mlid-782" role="menuitem"><a href="/page/content/Ads" data-hide-link-title="0" class="" data-icon-position="">Advertisers</a></li>
<li class="leaf menu-mlid-790" role="menuitem"><a href="/alerts" data-hide-link-title="0" class="" data-icon-position="">Alerts</a></li>
<li class="last leaf menu-mlid-791" role="menuitem"><a href="/feedback" class="" data-icon-position="" data-hide-link-title="0">Feedback</a></li>
</ul></nav></li>
</ul></nav></div>
  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
<div class="panel-pane pane-panels-mini pane-responsive-menu-user-menu" >
  
        <h2 class="pane-title"><span class="icon-gear"></span><span class="element-invisible">User menu</span></h2>
    
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-responsive_menu_user_menu">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-menu-tree pane-user-menu" >
  
      
  
  <div class="pane-content">
    <div class="menu-block-wrapper menu-block-ctools-user-menu-1 menu-name-user-menu parent-mlid-user-menu:0 menu-level-1">
  <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf menu-mlid-801" role="menuitem"><a href="/content/subscriber-help-and-services" data-hide-link-title="0" class="" data-icon-position="">Subscribe</a></li>
<li class="leaf menu-mlid-802" role="menuitem"><a href="/alerts" data-hide-link-title="0" class="" data-icon-position="">Alerts</a></li>
<li class="leaf menu-mlid-803" role="menuitem"><a href="/user/login?destination=/content/31/5/838%3Fvariant%3Dabstract" class="" data-icon-position="" data-hide-link-title="0">Log in</a></li>
<li class="last leaf menu-mlid-17" role="menuitem"><a href="/user/logout?current=node/9880" class="" data-icon-position="" data-hide-link-title="0">Log out</a></li>
</ul></nav></div>
  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-user-identities" >
  
      
  
  <div class="pane-content">
    <div class="highwire-user-message" data-separator="|"><span class="highwire-user-institution" data-id-type="institution" data-identity="a%3A2%3A%7Bs%3A4%3A%22show%22%3Bi%3A1%3Bs%3A7%3A%22message%22%3Bs%3A50%3A%22Institution%3A%20%5Bidentity%3Ainstitutional_display_name%5D%22%3B%7D"></span></div>  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
<div class="panel-pane pane-panels-mini pane-responsive-menu-search" >
  
        <h2 class="pane-title"><span class="icon-search"></span><span class="element-invisible">Search</span></h2>
    
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-responsive_menu_search">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-seach-qsearch-nocontext" >
  
      
  
  <div class="pane-content">
    <form class="highwire-quicksearch button-style-mini button-style-mini" action="/content/31/5/838.abstract" method="post" id="highwire-search-qsearch-nocontext-form" accept-charset="UTF-8"><div><div class="form-item form-item-label-invisible form-type-textfield form-item-keywords">
  <label class="element-invisible" for="quick_search_header_keywords_254812226">Search for this keyword </label>
 <input placeholder="Search..." type="text" id="quick_search_header_keywords_254812226" name="keywords" value="" size="60" maxlength="128" class="form-text" />
</div>
<div class="button-wrapper button-mini"><span class="icon-search"></span><input data-icon-only="1" data-font-icon="icon-search" data-icon-position="after" type="submit" id="quick_search_header_submit_1047638686" name="op" value="Search" class="form-submit" /></div><input type="hidden" name="form_build_id" value="form-YwSOnfKg163A095hIqNA4gVwkL4JlkaLcRSvag5pZ70" />
<input type="hidden" name="form_id" value="highwire_search_qsearch_nocontext_form" />
</div></form>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-custom pane-1 highwire-responsive-advanced-search-link pane-menu-tree" >
  
      
  
  <div class="pane-content">
    <ul class="menu">
  <li><a href="/search" title="Advanced search">Advanced search</a></li>
  </ul>  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
</div></div>
  </div>
</div>
    </div>
  </div>
</div><div class="block block-panels-mini block-hw-small-logo block-panels-mini-hw-small-logo even block-without-title" id="block-panels-mini-hw-small-logo">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-hw_small_logo">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-small-logo" >
  
      
  
  <div class="pane-content">
    <a href="/" class="" data-icon-position="" data-hide-link-title="0"><img src="http://ajnr-stage2.stage.highwire.org/sites/default/files/ajnr-logo.png" alt="American Journal of Neuroradiology" title="American Journal of Neuroradiology" /></a>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>  </div>
</div>  </div>
</div><div id="zone-user-wrapper" class="zone-wrapper zone-user-wrapper clearfix mobile-hidden print-hidden">  
  <div id="zone-user" class="zone zone-user clearfix equal-height-container mobile-hidden print-hidden container-30">    
  	    <div class="grid-30 region region-user-second equal-height-element" id="region-user-second">
  <div class="region-inner region-user-second-inner">
    <div class="block block-panels-mini text-right no-margin-bottom block-jnl-ajnr-uid-strng block-panels-mini-jnl-ajnr-uid-strng odd block-without-title" id="block-panels-mini-jnl-ajnr-uid-strng">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_uid_strng">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-user-identities" >
  
      
  
  <div class="pane-content">
    <div class="highwire-user-message" data-separator=" | "><span class="highwire-user-institution" data-id-type="institution" data-identity="a%3A2%3A%7Bs%3A4%3A%22show%22%3Bi%3A1%3Bs%3A7%3A%22message%22%3Bs%3A85%3A%22%3Cspan%20class%3D%22narrow-hidden%22%3EInstitution%3A%20%3C%2Fspan%3E%5Bidentity%3Ainstitutional_display_name%5D%22%3B%7D"></span></div>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>  </div>
</div>  </div>
</div>  
  <div id="zone-branding" class="zone zone-branding clearfix mobile-hidden print-display-block container-30">
    <div class="grid-19 prefix-1 region region-branding print-display-block" id="region-branding">
  <div class="region-inner region-branding-inner">
        <div class="branding-data clearfix">
            <div class="logo-img">
        <a href="/" rel="home" class="" data-icon-position="" data-hide-link-title="0"><img alt="American Journal of Neuroradiology" src="http://ajnr-stage2.stage.highwire.org/sites/default/files/ajnr-web-logo_0.png" /></a>      </div>
                        <hgroup class="site-name-slogan element-invisible">        
                                <h2 class="site-name element-invisible"><a href="/" title="Home" class="" data-icon-position="" data-hide-link-title="0">American Journal of Neuroradiology</a></h2>
                              </hgroup>
          </div>
          </div>
</div><div class="grid-9 suffix-1 region region-branding-second print-hidden" id="region-branding-second">
  <div class="region-inner region-branding-second-inner">
    <div class="block block-panels-mini text-right no-margin-bottom block-jnl-ajnr-user-menu block-panels-mini-jnl-ajnr-user-menu odd block-without-title" id="block-panels-mini-jnl-ajnr-user-menu">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_user_menu">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-block pane-system-user-menu links inline pane-system" >
  
      
  
  <div class="pane-content">
    <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf" role="menuitem"><a href="/content/subscriber-help-and-services" data-hide-link-title="0" class="" data-icon-position="">Subscribe</a></li>
<li class="leaf" role="menuitem"><a href="/alerts" data-hide-link-title="0" class="" data-icon-position="">Alerts</a></li>
<li class="leaf" role="menuitem"><a href="/user/login?destination=/content/31/5/838%3Fvariant%3Dabstract" class="" data-icon-position="" data-hide-link-title="0">Log in</a></li>
<li class="last leaf" role="menuitem"><a href="/user/logout?current=node/9880" class="" data-icon-position="" data-hide-link-title="0">Log out</a></li>
</ul></nav>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div><div class="block block-panels-mini block-jnl-ajnr-search-box block-panels-mini-jnl-ajnr-search-box even block-without-title" id="block-panels-mini-jnl-ajnr-search-box">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_search_box">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-seach-quicksearch no-margin-bottom" >
  
      
  
  <div class="pane-content">
    <form class="highwire-quicksearch button-style-mini button-style-mini" action="/content/31/5/838.abstract" method="post" id="highwire-search-quicksearch-form-0" accept-charset="UTF-8"><div><div class="form-item form-item-label-invisible form-type-textfield form-item-keywords">
  <label class="element-invisible" for="search_rightsidebar_keywords_1406277166">Search for this keyword </label>
 <input placeholder="search" type="text" id="search_rightsidebar_keywords_1406277166" name="keywords" value="" size="60" maxlength="128" class="form-text" />
</div>
<div class="button-wrapper button-mini"><span class="icon-search"></span><input data-icon-only="1" data-font-icon="icon-search" data-icon-position="after" type="submit" id="search_rightsidebar_submit_988176064" name="op" value="Search" class="form-submit" /></div><input type="hidden" name="form_build_id" value="form-mxqS39vnnNlBhBlztA8nsN1T0ZWePnoYCknmeOdOgso" />
<input type="hidden" name="form_id" value="highwire_search_quicksearch_form_0" />
</div></form>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-custom pane-2" >
  
      
  
  <div class="pane-content">
    <p><a href="/search">Advanced Search</a></p>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>  </div>
</div>  </div>
  
  <div id="zone-menu" class="zone zone-menu clearfix mobile-hidden container-30">
    <div class="grid-28 suffix-1 prefix-1 region region-menu region-menu-bg-opaque region-menu-no-border" id="region-menu">
  <div class="region-inner region-menu-inner">
        <div class="block block-nice-menus block-1 block-nice-menus-1 odd block-without-title" id="block-nice-menus-1">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <nav class="menubar-nav"><ul class="nice-menu nice-menu-down nice-menu-main-menu" id="nice-menu-1" role="menu"><li class="menu-772 menu-path-front first odd " role="menuitem"><a href="/" class="" data-icon-position="" data-hide-link-title="0">Home</a></li>
<li class="menu-773 menuparent  menu-path-content-current active-trail  even " role="menuitem"><a href="/content/current" data-hide-link-title="0" class="active" data-icon-position="">Content</a><ul role="menu"><li class="menu-774 menu-path-content-current first odd " role="menuitem"><a href="/content/current" data-hide-link-title="0" class="" data-icon-position="">Current Issue</a></li>
<li class="menu-1747 menu-path-content-early-preprint  even " role="menuitem"><a href="/content/early/preprint" data-hide-link-title="0" class="" data-icon-position="">Publication Preview--Preprint</a></li>
<li class="menu-775 menu-path-content-early-recent  odd " role="menuitem"><a href="/content/early/recent" data-hide-link-title="0" class="" data-icon-position="">Publication Preview--Ahead of Print</a></li>
<li class="menu-776 menu-path-content-by-year  even " role="menuitem"><a href="/content/by/year" data-hide-link-title="0" class="" data-icon-position="">Past Issue Archive</a></li>
<li class="menu-900 menu-path-cow-by-year  odd " role="menuitem"><a href="/cow/by/year" data-hide-link-title="0" class="" data-icon-position="">Case of the Week Archive</a></li>
<li class="menu-1006 menu-path-cc-by-year  even " role="menuitem"><a href="/cc/by/year" data-hide-link-title="0" class="" data-icon-position="">Classic Case Archive</a></li>
<li class="menu-901 menu-path-com-by-year  odd " role="menuitem"><a href="/com/by/year" data-hide-link-title="0" class="" data-icon-position="">Case of the Month Archive</a></li>
<li class="menu-1334 menu-path-ajnrorg-content-covid-19-content-and-resources  even last" role="menuitem"><a href="http://www.ajnr.org/content/covid-19-content-and-resources" data-hide-link-title="0" class="" data-icon-position="">COVID-19 Content and Resources</a></li>
</ul></li>
<li class="menu-784 menuparent  menu-path-node-7  odd " role="menuitem"><a href="/content/about-us" class="" data-icon-position="" data-hide-link-title="0">About Us</a><ul role="menu"><li class="menu-785 menu-path-node-935 first odd " role="menuitem"><a href="/page/content/About" data-hide-link-title="0" class="" data-icon-position="">About AJNR</a></li>
<li class="menu-899 menu-path-sajnrorg-page-content-ed-board  even " role="menuitem"><a href="https://www.ajnr.org/page/content/Ed-Board" data-hide-link-title="0" class="" data-icon-position="">Editorial Board</a></li>
<li class="menu-864 menu-path-asnrorg  odd last" role="menuitem"><a href="http://www.asnr.org" data-hide-link-title="0" target="_blank" class="" data-icon-position="">American Society of Neuroradiology</a></li>
</ul></li>
<li class="menu-1746 menuparent  menu-path-front  even " role="menuitem"><a href="/" class="" data-icon-position="" data-hide-link-title="0">For Authors</a><ul role="menu"><li class="menu-1725 menu-path-sajnrorg-content-author-policies first odd " role="menuitem"><a href="https://www.ajnr.org/content/author-policies" data-hide-link-title="0" class="" data-icon-position="">Author Policies</a></li>
<li class="menu-1856 menu-path-sajnrorg-preprint-publishing  even " role="menuitem"><a href="https://www.ajnr.org/preprint_publishing" data-hide-link-title="0" class="" data-icon-position="">Preprint Publishing</a></li>
<li class="menu-1726 menu-path-sajnrorg-content-manuscript-submission-guidelines  odd last" role="menuitem"><a href="https://www.ajnr.org/content/manuscript-submission-guidelines" data-hide-link-title="0" class="" data-icon-position="">Manuscript Submission Guidelines</a></li>
</ul></li>
<li class="menu-862 menu-path-smcmanuscriptcentralcom-ajnr  odd " role="menuitem"><a href="https://mc.manuscriptcentral.com/ajnr" data-hide-link-title="0" target="_blank" class="" data-icon-position="">Submit a Manuscript</a></li>
<li class="menu-1184 menuparent  menu-path-node-7  even " role="menuitem"><a href="/content/about-us" data-hide-link-title="0" class="" data-icon-position="">Special Collections</a><ul role="menu"><li class="menu-1733 menu-path-ajnrorg-cc-csf-spinal-leak first odd " role="menuitem"><a href="http://www.ajnr.org/cc/CSF-Spinal-Leak" data-hide-link-title="0" class="" data-icon-position="">Spinal CSF Leak Articles (Jan 2020-June 2024)</a></li>
<li class="menu-1185 menu-path-ajnrorg-cc-most-impactful-ajnr-articles  even " role="menuitem"><a href="http://www.ajnr.org/cc/most-impactful-ajnr-articles" data-hide-link-title="0" class="" data-icon-position="">Most Impactful AJNR Articles</a></li>
<li class="menu-1896 menu-path-ajnrorg-cc-2024-awards  odd last" role="menuitem"><a href="http://www.ajnr.org/cc/2024-Awards" data-hide-link-title="0" class="" data-icon-position="">2024 AJNR Journal Awards</a></li>
</ul></li>
<li class="menu-788 menuparent  menu-path-node-9  odd last" role="menuitem"><a href="/content/advertising" class="" data-icon-position="" data-hide-link-title="0">More</a><ul role="menu"><li class="menu-780 menu-path-node-960 first odd " role="menuitem"><a href="/content/subscriber-help-and-services" data-hide-link-title="0" class="" data-icon-position="">Subscribers</a></li>
<li class="menu-863 menu-path-smarketplacecopyrightcom-rs-ui-web-mp-details-journal-122810747  even " role="menuitem"><a href="https://marketplace.copyright.com/rs-ui-web/mp/details/journal/122810747" data-hide-link-title="0" class="" data-icon-position="">Permissions</a></li>
<li class="menu-782 menu-path-node-937  odd " role="menuitem"><a href="/page/content/Ads" data-hide-link-title="0" class="" data-icon-position="">Advertisers</a></li>
<li class="menu-790 menu-path-alerts  even " role="menuitem"><a href="/alerts" data-hide-link-title="0" class="" data-icon-position="">Alerts</a></li>
<li class="menu-791 menu-path-node-10  odd last" role="menuitem"><a href="/feedback" class="" data-icon-position="" data-hide-link-title="0">Feedback</a></li>
</ul></li>
</ul></nav>
    </div>
  </div>
</div><div class="block block-menu text-right block-menu-social-media block-menu-menu-social-media even block-without-title" id="block-menu-menu-social-media">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf" role="menuitem"><a href="http://www.twitter.com/TheAJNR" target="_blank" class="link-icon-only link-icon"><span class="hw-icon-x-twitter"></span> <span class="title element-invisible">Follow AJNR on Twitter</span></a></li>
<li class="leaf" role="menuitem"><a href="http://www.facebook.com/AmJNeuroradiol" target="_blank" class="link-icon-only link-icon"><span class="icon-facebook-sign icon-2x"></span> <span class="title element-invisible">Visit AJNR on Facebook</span></a></li>
<li class="leaf" role="menuitem"><a href="https://www.instagram.com/the_ajnr/?hl=en" class="link-icon-only link-icon"><span class="icon-instagram icon-2x"></span> <span class="title element-invisible">Follow AJNR on Instagram</span></a></li>
<li class="leaf" role="menuitem"><a href="https://www.linkedin.com/company/american-journal-of-neuroradiology" class="link-icon-only link-icon"><span class="icon-linkedin icon-2x"></span> <span class="title element-invisible">Join AJNR on LinkedIn</span></a></li>
<li class="last leaf" role="menuitem"><a href="/rss" class="link-icon-only link-icon"><span class="icon-rss icon-2x"></span> <span class="title element-invisible">RSS Feeds</span></a></li>
</ul></nav>    </div>
  </div>
</div>  </div>
</div>
  </div>
  
  <div id="zone-header" class="zone zone-header clearfix container-30">
  	      </div>
</header>    
      <section id="section-content" class="section section-content">
    
  <div id="zone-content" class="zone zone-content clearfix container-30">    
        
    <div class="grid-28 suffix-1 prefix-1 region region-content" id="region-content">
  <div class="region-inner region-content-inner">
    <a id="main-content"></a>
                        <div class="block block-system block-main block-system-main odd block-without-title" id="block-system-main">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panels-960-layout jcore-2col-layout" >
	  <div class="panel-row-wrapper panel-row-first clearfix">
		
		<div class="top-wrapper">
			<div class="panel-panel panel-region-top">
			  <div class="inside"><div class="panel-pane pane-highwire-article-citation" >
  
      
  
  <div class="pane-content">
    <div class="highwire-article-citation highwire-citation-type-highwire-article node9880--5" data-node-nid="9880" id="top-node-9880--61324611325" data-pisa="ajnr;31/5/838" data-pisa-master="ajnr;ajnr.A1941" data-apath="/ajnr/31/5/838.atom" data-hw-author-tooltip-instance="highwire_author_tooltip"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-article-title-complete clearfix has-author-tooltip highwire-citation-highwire-article-top-a">
  
  
      <div class="highwire-cite-overline"><span  class="highwire-cite-metadata-article-type highwire-cite-metadata">Research Article</span><span class="separator-pipe"></span><span  class="highwire-cite-metadata-art-cat highwire-cite-metadata"><span class="wrapper">Spine</span></span></div>
  
      <div class="highwire-cite-access"><span class="highwire-citation-access highwire-citation-access-check" data-pisa-id="ajnr;ajnr.A1941" data-atom-uri="/ajnr/31/5/838.atom" data-request-view="full"></span></div>
  
      <h1 class="highwire-cite-title" id="page-title">Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images</h1>  
    	<div class="highwire-cite-authors"><span  class="highwire-citation-authors"><span class="highwire-citation-author first" data-delta="0">S.-C. Hung</span>, <span class="highwire-citation-author" data-delta="1">H.-M. Wu</span> and <span class="highwire-citation-author" data-delta="2">W.-Y. Guo</span></span></div>
  
    	<div class="highwire-cite-metadata"><span  class="highwire-cite-metadata-journal highwire-cite-metadata">American Journal of Neuroradiology </span><span  class="highwire-cite-metadata-date highwire-cite-metadata">May 2010,  </span><span  class="highwire-cite-metadata-volume highwire-cite-metadata">31 </span><span  class="highwire-cite-metadata-issue highwire-cite-metadata">(5) </span><span  class="highwire-cite-metadata-pages highwire-cite-metadata">838-843; </span><span  class="highwire-cite-metadata-doi highwire-cite-metadata">DOI: https://doi.org/10.3174/ajnr.A1941 </span></div>
  
  
  
</div>
<div id="hw-article-author-popups-top-node-9880--61324611325" style="display: none;"><div class="author-tooltip-0"><div class="author-tooltip-name">S.-C. Hung </div><ul class="author-tooltip-find-more"><li class="author-tooltip-gs-link first"><a href="/lookup/google-scholar?link_type=googlescholar&amp;gs_type=author&amp;author%5B0%5D=S.-C.%2BHung%2B" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on Google Scholar</a></li><li class="author-tooltip-pubmed-link"><a href="/lookup/external-ref?access_num=Hung%20S&amp;link_type=AUTHORSEARCH" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on PubMed</a></li><li class="author-site-search-link last"><a href="/search/author1%3AS.-C.%2BHung%2B" rel="nofollow" class="" data-icon-position="" data-hide-link-title="0">Search for this author on this site</a></li></ul></div><div class="author-tooltip-1"><div class="author-tooltip-name">H.-M. Wu </div><ul class="author-tooltip-find-more"><li class="author-tooltip-gs-link first"><a href="/lookup/google-scholar?link_type=googlescholar&amp;gs_type=author&amp;author%5B0%5D=H.-M.%2BWu%2B" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on Google Scholar</a></li><li class="author-tooltip-pubmed-link"><a href="/lookup/external-ref?access_num=Wu%20H&amp;link_type=AUTHORSEARCH" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on PubMed</a></li><li class="author-site-search-link last"><a href="/search/author1%3AH.-M.%2BWu%2B" rel="nofollow" class="" data-icon-position="" data-hide-link-title="0">Search for this author on this site</a></li></ul></div><div class="author-tooltip-2"><div class="author-tooltip-name">W.-Y. Guo </div><ul class="author-tooltip-find-more"><li class="author-tooltip-gs-link first"><a href="/lookup/google-scholar?link_type=googlescholar&amp;gs_type=author&amp;author%5B0%5D=W.-Y.%2BGuo%2B" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on Google Scholar</a></li><li class="author-tooltip-pubmed-link"><a href="/lookup/external-ref?access_num=Guo%20W&amp;link_type=AUTHORSEARCH" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Find this author on PubMed</a></li><li class="author-site-search-link last"><a href="/search/author1%3AW.-Y.%2BGuo%2B" rel="nofollow" class="" data-icon-position="" data-hide-link-title="0">Search for this author on this site</a></li></ul></div></div></div>  </div>

  
  </div>
</div>
			</div>
		</div>
	
	</div> <!-- /.panel-row-wrapper -->	
	  
  <div class="panel-row-wrapper clearfix">
		
		<div class="main-content-wrapper grid-17 suffix-1 alpha">
			<div class="panel-panel panel-region-content">
			  <div class="inside"><div class="panel-pane pane-highwire-panel-tabs pane-panels-ajax-tab-tabs" >
  
      
  
  <div class="pane-content">
    <div class="item-list"><ul class="tabs inline panels-ajax-tab"><li class="first"><a href="/content/31/5/838" class="panels-ajax-tab-tab" data-panel-name="jnl_ajnr_tab_art" data-target-id="highwire_article_tabs" data-entity-context="node:9880" data-trigger="" data-url-enabled="1">Article</a><a href="/panels_ajax_tab/jnl_ajnr_tab_art/node:9880/1" rel="nofollow" style="display:none" class="js-crawler-link"></a></li><li><a href="/content/31/5/838/tab-figures-data" class="panels-ajax-tab-tab" data-panel-name="jnl_ajnr_tab_data" data-target-id="highwire_article_tabs" data-entity-context="node:9880" data-trigger="tab-figures-data" data-url-enabled="1">Figures &amp; Data</a><a href="/panels_ajax_tab/jnl_ajnr_tab_data/node:9880/1" rel="nofollow" style="display:none" class="js-crawler-link"></a></li><li><a href="/content/31/5/838/tab-references" class="panels-ajax-tab-tab" data-panel-name="jnl_ajnr_tab_refs" data-target-id="highwire_article_tabs" data-entity-context="node:9880" data-trigger="tab-references" data-url-enabled="1">References</a><a href="/panels_ajax_tab/jnl_ajnr_tab_refs/node:9880/1" rel="nofollow" style="display:none" class="js-crawler-link"></a></li><li><a href="/content/31/5/838/tab-article-info" class="panels-ajax-tab-tab" data-panel-name="jnl_ajnr_tab_info" data-target-id="highwire_article_tabs" data-entity-context="node:9880" data-trigger="tab-article-info" data-url-enabled="1">Info &amp; Metrics</a><a href="/panels_ajax_tab/jnl_ajnr_tab_info/node:9880/1" rel="nofollow" style="display:none" class="js-crawler-link"></a></li><li class="last"><a href="/content/ajnr/31/5/838.full.pdf" class="panels-ajax-tab-tab" data-panel-name="jnl_ajnr_tab_pdf" data-target-id="highwire_article_tabs" data-entity-context="node:9880" data-trigger="tab-pdf" data-url-enabled="1"><i class="icon-file-alt"></i> PDF</a><a href="/panels_ajax_tab/jnl_ajnr_tab_pdf/node:9880/1" rel="nofollow" style="display:none" class="js-crawler-link"></a></li></ul></div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-panel-tabs-container" >
  
      
  
  <div class="pane-content">
    <div data-panels-ajax-tab-preloaded="jnl_ajnr_tab_art" id="panels-ajax-tab-container-highwire_article_tabs" class="panels-ajax-tab-container"><div class="panels-ajax-tab-loading" style ="display:none"><img class="loading" src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/contrib/panels_ajax_tab/images/loading.gif" alt="Loading" title="Loading" /></div><div class="panels-ajax-tab-wrap-jnl_ajnr_tab_art"><div class="panel-display panel-1col clearfix" >
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-markup" >
  
      
  
  <div class="pane-content">
    <div class="highwire-markup"><div xmlns="http://www.w3.org/1999/xhtml" data-highwire-cite-ref-tooltip-instance="highwire_reflinks_tooltip" class="content-block-markup" xmlns:xhtml="http://www.w3.org/1999/xhtml"><div class="article abstract-view"><span class="highwire-journal-article-marker-start"></span><div class="section abstract" id="abstract-1"><h2>Abstract</h2>
<div id="sec-1" class="subsection">

<p id="p-1"><strong>BACKGROUND AND PURPOSE:</strong> The ADI is the imaging diagnostic clue to AAA subluxation of the cervical spine. Some MR imaging findings other than abnormal ADI relate to AAA subluxation. However, their relationship is not yet clarified. The present study elucidates the role of MR imaging by employing these previously overlooked findings.</p>
</div>
<div id="sec-2" class="subsection">

<p id="p-2"><strong>MATERIALS AND METHODS:</strong> This study enrolled 40 patients with AAA subluxation and 20 non-AAA subluxation patients as controls. All MR imaging was performed with supine neutral positioning. The morphology of the dens, bilateral facet joints, and surrounding ligaments, as well as the alignment of the anterior atlantoaxial joint, the spinolaminar line, and the intramedullary signal intensity, were assessed. This investigation statistically analyzed the difference among these groups.</p>
</div>
<div id="sec-3" class="subsection">

<p id="p-3"><strong>RESULTS:</strong> Thirty-eight percent (15 of 40) of patients with AAA subluxation showed nAAA. There was no significant difference between the groups of AAA with normal and abnormal ADI except that more peridental pannus was seen in the latter group. More dens erosion (<em>P</em> = .022), tilting of anterior atlantoaxial joint (<em>P</em> = .022), peridental effusion (<em>P</em> &lt; .001), lateral facet arthropathy (<em>P</em> &lt; .001), abnormal spinolaminar line (<em>P</em> = .001), and focal myelopathy (<em>P</em> = .001) were observed in nAAA patients compared with the controls. The combination of peridental effusion, lateral facet arthropathy, abnormal intramedullary signals, and abnormal spinolaminar line showed a sensitivity of 100% and a specificity of 90% in diagnosing AAA subluxation.</p>
</div>
<div id="sec-4" class="subsection">

<p id="p-4"><strong>CONCLUSIONS:</strong> MR imaging provides important biomechanical clues, other than ADI, that improve accuracy in diagnosing atlantoaxial instability.</p>
</div>
</div><div class="section glossary" id="glossary-1"><h2>Abbreviations</h2><dl id="def-list-1"><dt id="def-item-1">AAA subluxation<span class="def-item-dt-sep"></span></dt><dd>anterior atlantoaxial subluxation<span class="def-item-dd-sep"></span></dd><dt id="def-item-2">aAAA subluxation<span class="def-item-dt-sep"></span></dt><dd>anterior atlantoaxial subluxation with abnormal atlantodental interval<span class="def-item-dd-sep"></span></dd><dt id="def-item-3">nAAA subluxation<span class="def-item-dt-sep"></span></dt><dd>anterior atlantoaxial subluxation with normal atlantodental interval<span class="def-item-dd-sep"></span></dd><dt id="def-item-4">ADI<span class="def-item-dt-sep"></span></dt><dd>atlantodental interval<span class="def-item-dd-sep"></span></dd><dt id="def-item-5">ALL<span class="def-item-dt-sep"></span></dt><dd>anterior longitudinal ligament<span class="def-item-dd-sep"></span></dd><dt id="def-item-6">FSE<span class="def-item-dt-sep"></span></dt><dd>fast spin-echo<span class="def-item-dd-sep"></span></dd><dt id="def-item-7">NS<span class="def-item-dt-sep"></span></dt><dd>not significant<span class="def-item-dd-sep"></span></dd><dt id="def-item-8">PD<span class="def-item-dt-sep"></span></dt><dd>predental<span class="def-item-dd-sep"></span></dd><dt id="def-item-9">RD<span class="def-item-dt-sep"></span></dt><dd>retrodental<span class="def-item-dd-sep"></span></dd><dt id="def-item-10">SD<span class="def-item-dt-sep"></span></dt><dd>supradental<span class="def-item-dd-sep"></span></dd><dt id="def-item-11">TM<span class="def-item-dt-sep"></span></dt><dd>tectorial membrane</dd></dl></div><ul class="copyright-statement"><li class="fn" id="copyright-statement-1">Copyright © American Society of Neuroradiology</li></ul><span class="highwire-journal-article-marker-end"></span></div><span class="related-urls"></span></div><a href="http://ajnr-stage2.stage.highwire.org/content/31/5/838.full" class="hw-link hw-link-article-full-text" data-icon-position="" data-hide-link-title="0">View Full Text</a></div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-article-trendmd" >
  
      
  
  <div class="pane-content">
    <div id="trendmd-suggestions"></div>  </div>

  
  </div>
</div>
  </div>
</div>
</div></div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-node-pager" >
  
      
  
  <div class="pane-content">
    <div class="pager highwire-pager pager-mini clearfix highwire-node-pager highwire-article-pager"><span class="pager-prev"><a href="/content/31/5/832" title="Adult Lumbar Scoliosis: Underreported on Lumbar MR Scans" rel="prev" class="pager-link-prev link-icon"><span class="icon-circle-arrow-left"></span> <span class="title">Previous</span></a></span><span class="pager-next"><a href="/content/31/5/844" title="Mass Effect in the Thoracic Spine from Remnant Bone Wax: An MR Imaging Pitfall" rel="next" class="pager-link-next link-icon-right link-icon"><span class="title">Next</span> <span class="icon-circle-arrow-right"></span></a></span></div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-back-to-top" >
  
      
  
  <div class="pane-content">
    <a href="#page" class="back-to-top" data-icon-position="" data-hide-link-title="0"><span class="icon-chevron-up"></span> Back to top</a>  </div>

  
  </div>
</div>
			</div>
		</div>
		
		<div class="sidebar-right-wrapper grid-10 omega">
			<div class="panel-panel panel-region-sidebar-right">
			  <div class="inside"><div class="panel-pane pane-panels-mini pane-jnl-ajnr-art-issue pane-style-alt-content" >
  
        <h2 class="pane-title">In this issue</h2>
    
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_art_issue">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-article-citation" >
  
      
  
  <div class="pane-content">
    <div class="highwire-article-citation highwire-citation-type-highwire-issue node1641" data-node-nid="1641" id="node-1641--262349022" data-pisa="ajnr;31/5" data-pisa-master="ajnr;31/5" data-apath="/ajnr/31/5.atom"><div class="highwire-cite highwire-cite-highwire-issue highwire-citation-jcore-issue-widget clearfix">
    
      <div class="highwire-cite-highlight"><a href="/content/31/5"  class="highlight-image-linked"><img class="highlight-image" src="http://ajnr-stage2.stage.highwire.org/sites/default/files/styles/medium/public/highwire/ajnr/31/5.cover.gif?itok=PxCUBETR" alt="American Journal of Neuroradiology: 31 (5)" /></a></div>
  
  <div class="highwire-cite-col">
      
      
          <a href="/content/31/5" class="highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title">American Journal of Neuroradiology</span></a>      
      
        	<div class="highwire-cite-metadata"><span  class="highwire-cite-metadata-volume highwire-cite-metadata">Vol. 31</span>, <span  class="highwire-cite-metadata-issue highwire-cite-metadata">Issue 5 </span><div  class="highwire-cite-metadata-pubdate highwire-cite-metadata">1 May 2010 </div></div>
      
      
        	<div class="highwire-cite-extras"><div class='highwire-article-citation-variant-list'><ul class="links variants-list"><li class="toc first"><a href="/content/31/5.toc" class="highwire-variant-link variant-toc " title="Table of Contents" rel="alternate" type="text/html" data-icon-position="" data-hide-link-title="0">Table of Contents</a></li><li class="index-by-author last"><a href="/content/31/5.index-by-author" class="highwire-variant-link variant-index-by-author " title="Index by author" rel="alternate" data-icon-position="" data-hide-link-title="0">Index by author</a></li></ul></div></div>
      </div>

</div></div>  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-panels-mini pane-jnl-ajnr-ad-rhs" >
  
      
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_ad_rhs">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-dfp-pane text-center" >
  
      
  
  <div class="pane-content">
    <div id="dfp-ad-rhs-wrapper" class="dfp-tag-wrapper">
<div class="slug">Advertisement</div>
<div  id="dfp-ad-rhs" class="dfp-tag-wrapper">
  <script type="text/javascript">
    googletag.cmd.push(function() {
      googletag.display("dfp-ad-rhs");
    });
  </script>
</div>
</div>  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-panels-mini pane-jnl-ajnr-art-tools" >
  
      
  
  <div class="pane-content">
    <div id="mini-panel-jnl_ajnr_art_tools" class="highwire-2col-stacked panel-display">
	  
  <div class="panel-row-wrapper clearfix">
		<div class="content-left-wrapper content-column">
          <div class="panel-panel panel-region-content-left">
            <div class="inside"><div class="panel-pane pane-highwire-variant-link" >
  
      
  
  <div class="pane-content">
    <a href="/content/ajnr/31/5/838.full-text.print" target="_blank" rel="nofollow" class="link-icon"><span class="icon-print"></span> <span class="title">Print</span></a>  </div>

  
  </div>
<div class="panel-pane pane-highwire-variant-link text-no-wrap" >
  
      
  
  <div class="pane-content">
    <a href="/content/ajnr/31/5/838.full-text.pdf" target="_blank" class="link-icon"><span class="icon-download-alt"></span> <span class="title">Download PDF</span></a>  </div>

  
  </div>
<div class="panel-pane pane-minipanel-dialog-link pane-jnl-ajnr-art-email" >
  
      
  
  <div class="pane-content">
    <div class='minipanel-dialog-wrapper'><div class='minipanel-dialog-link-link'><a href="/" oncontextmenu="javascript: return false;" class="minipanel-dialog-link-trigger link-icon" title="Email this Article"><span class="icon-envelope"></span> <span class="title">Email Article</span></a></div><div class='minipanel-dialog-link-mini' style='display:none'><div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_art_email">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-block pane-forward-form pane-forward" >
  
      
  
  <div class="pane-content">
    <form action="/content/31/5/838.abstract" method="post" id="forward-form" accept-charset="UTF-8"><div><div id="edit-instructions" class="form-item form-item-label-before form-type-item">
 <p>Thank you for your interest in spreading the word on American Journal of Neuroradiology.</p><p>NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.</p>
</div>
<div class="form-item form-item-label-before form-type-textfield form-item-email">
  <label for="edit-email">Your Email <span class="form-required" title="This field is required.">*</span></label>
 <input type="text" id="edit-email" name="email" value="" size="58" maxlength="256" class="form-text required" />
</div>
<div class="form-item form-item-label-before form-type-textfield form-item-name">
  <label for="edit-name">Your Name <span class="form-required" title="This field is required.">*</span></label>
 <input type="text" id="edit-name" name="name" value="" size="58" maxlength="256" class="form-text required" />
</div>
<div class="form-item form-item-label-before form-type-textarea form-item-recipients">
  <label for="edit-recipients">Send To <span class="form-required" title="This field is required.">*</span></label>
 <div class="form-textarea-wrapper resizable"><textarea id="edit-recipients" name="recipients" cols="50" rows="5" class="form-textarea required"></textarea></div>
<div class="description">Enter multiple addresses on separate lines or separate them with commas.</div>
</div>
<div id="edit-page" class="form-item form-item-label-before form-type-item">
  <label for="edit-page">You are going to email the following </label>
 <a href="/content/31/5/838" class="active" data-icon-position="" data-hide-link-title="0">Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images</a>
</div>
<div id="edit-subject" class="form-item form-item-label-before form-type-item">
  <label for="edit-subject">Message Subject </label>
 (Your Name) has sent you a message from American Journal of Neuroradiology
</div>
<div id="edit-body" class="form-item form-item-label-before form-type-item">
  <label for="edit-body">Message Body </label>
 (Your Name) thought you would like to see the American Journal of Neuroradiology web site.
</div>
<div class="form-item form-item-label-before form-type-textarea form-item-message">
  <label for="edit-message--2">Your Personal Message </label>
 <div class="form-textarea-wrapper resizable"><textarea id="edit-message--2" name="message" cols="50" rows="10" class="form-textarea"></textarea></div>
</div>
<input type="hidden" name="path" value="node/9880" />
<input type="hidden" name="path_cid" value="" />
<input type="hidden" name="forward_footer" value="" />
<input type="hidden" name="form_build_id" value="form-oE8Iams0J6K6f3L0RiSyAb_mnt9SmsJdkDG_dw2l04E" />
<input type="hidden" name="form_id" value="forward_form" />
<fieldset class="captcha form-wrapper"><legend><span class="fieldset-legend">CAPTCHA</span></legend><div class="fieldset-wrapper"><div class="fieldset-description">This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.</div><input type="hidden" name="captcha_sid" value="108726500" />
<input type="hidden" name="captcha_token" value="0dfa4380f9cdbcd8a173dd9fa3e0353e" />
<input type="hidden" name="captcha_response" value="Google no captcha" />
<div class="g-recaptcha" data-sitekey="6LfnJVIUAAAAAE-bUOMg0MJGki4lqSvDmhJp19fN" data-theme="light" data-type="image"></div></div></fieldset>
<div class="form-actions form-wrapper" id="edit-actions"><input type="submit" id="edit-submit" name="op" value="Send Message" class="form-submit" /></div></div></form>  </div>

  
  </div>
</div>
  </div>
</div>
</div></div>  </div>

  
  </div>
<div class="panel-pane pane-minipanel-dialog-link pane-jnl-ajnr-cite-tool" >
  
      
  
  <div class="pane-content">
    <div class='minipanel-dialog-wrapper'><div class='minipanel-dialog-link-link'><a href="/highwire/citation/9880/download" oncontextmenu="javascript: return false;" class="minipanel-dialog-link-trigger link-icon" title="Citation Tools"><span class="icon-globe"></span> <span class="title">Citation Tools</span></a></div><div class='minipanel-dialog-link-mini' style='display:none'><div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_cite_tool">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-citation-export" >
  
      
  
  <div class="pane-content">
    <div class="highwire-citation-export">  
  <div class="highwire-citation-info">
      <div class="highwire-article-citation highwire-citation-type-highwire-article cite-tool-node9880" data-node-nid="9880" id="citation-node-9880--2816729622" data-pisa="ajnr;31/5/838" data-pisa-master="ajnr;ajnr.A1941" data-apath="/ajnr/31/5/838.atom"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-standard clearfix">
  
  
  
  
      <div class="highwire-cite-title">Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images</div>  
    	<div class="highwire-cite-authors"><span  class="highwire-citation-authors"><span class="highwire-citation-author first" data-delta="0"><span class="nlm-given-names">S.-C.</span> <span class="nlm-surname">Hung</span></span>, <span class="highwire-citation-author" data-delta="1"><span class="nlm-given-names">H.-M.</span> <span class="nlm-surname">Wu</span></span>, <span class="highwire-citation-author" data-delta="2"><span class="nlm-given-names">W.-Y.</span> <span class="nlm-surname">Guo</span></span></span></div>
  
    	<div class="highwire-cite-metadata"><span  class="highwire-cite-metadata-journal highwire-cite-metadata">American Journal of Neuroradiology </span><span  class="highwire-cite-metadata-date highwire-cite-metadata">May 2010, </span><span  class="highwire-cite-metadata-volume highwire-cite-metadata">31 </span><span  class="highwire-cite-metadata-issue highwire-cite-metadata">(5) </span><span  class="highwire-cite-metadata-pages highwire-cite-metadata">838-843; </span><span  class="highwire-cite-metadata-doi highwire-cite-metadata"><span class="label">DOI:</span> 10.3174/ajnr.A1941 </span></div>
  
  
  
</div>
</div>  </div>
  <div class="highwire-citation-formats">
  	      <h2>Citation Manager Formats</h2>
        <div class="highwire-citation-formats-links">
      <span class="Z3988" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.spage=838&amp;rft.epage=843&amp;rft.atitle=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images&amp;rft.volume=31&amp;rft.issue=5&amp;rft.date=2010-05-01%2000%3A00%3A00&amp;rft.stitle&amp;rft.jtitle=American%20Journal%20of%20Neuroradiology&amp;rft.au=Hung%2C+S.-C.&amp;rft.au=Wu%2C+H.-M.&amp;rft.au=Guo%2C+W.-Y."></span><ul class="hw-citation-links inline button button-alt button-grid clearfix"><li class="bibtext first"><a href="/highwire/citation/9880/bibtext" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">BibTeX</a></li><li class="bookends"><a href="/highwire/citation/9880/bookends" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Bookends</a></li><li class="easybib"><a href="/highwire/citation/9880/easybib" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">EasyBib</a></li><li class="endnote-tagged"><a href="/highwire/citation/9880/endnote-tagged" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">EndNote (tagged)</a></li><li class="endnote-8-xml"><a href="/highwire/citation/9880/endnote-8-xml" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">EndNote 8 (xml)</a></li><li class="medlars"><a href="/highwire/citation/9880/medlars" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Medlars</a></li><li class="mendeley"><a href="/highwire/citation/9880/mendeley" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Mendeley</a></li><li class="papers"><a href="/highwire/citation/9880/papers" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Papers</a></li><li class="refworks-tagged"><a href="/highwire/citation/9880/refworks-tagged" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">RefWorks Tagged</a></li><li class="reference-manager"><a href="/highwire/citation/9880/reference-manager" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Ref Manager</a></li><li class="ris"><a href="/highwire/citation/9880/ris" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">RIS</a></li><li class="zotero last"><a href="/highwire/citation/9880/zotero" class="hw-download-citation-link" data-icon-position="" data-hide-link-title="0">Zotero</a></li></ul>    </div>
  </div>
</div>
  </div>

  
  </div>
</div>
  </div>
</div>
</div></div>  </div>

  
  </div>
</div>
          </div>
        </div>
        
        <div class="content-right-wrapper content-column">
          <div class="panel-panel panel-region-content-right">
            <div class="inside"><div class="panel-pane pane-highwire-share-link highwire_clipboard_link_ajax"  id="shareit">
  
      
  
  <div class="pane-content">
    <a href="/" class="link-icon"><span class="icon-share-alt"></span> <span class="title">Share</span></a>  </div>

  
  </div>
<div class="panel-pane pane-panels-mini pane-jnl-ajnr-share highwire_clipboard_form_ajax_shareit" >
  
      
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_share">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-highwire-article-citation large-margin-bottom" >
  
      
  
  <div class="pane-content">
    <div class="highwire-article-citation highwire-citation-type-highwire-article node9880--3" data-node-nid="9880" id="share-node-9880--41550093751" data-pisa="ajnr;31/5/838" data-pisa-master="ajnr;ajnr.A1941" data-apath="/ajnr/31/5/838.atom"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-standard clearfix">
  
  
  
  
      <div class="highwire-cite-title">Revisiting Anterior Atlantoaxial Subluxation with Overlooked Information on MR Images</div>  
    	<div class="highwire-cite-authors"><span  class="highwire-citation-authors"><span class="highwire-citation-author first" data-delta="0"><span class="nlm-given-names">S.-C.</span> <span class="nlm-surname">Hung</span></span>, <span class="highwire-citation-author" data-delta="1"><span class="nlm-given-names">H.-M.</span> <span class="nlm-surname">Wu</span></span>, <span class="highwire-citation-author" data-delta="2"><span class="nlm-given-names">W.-Y.</span> <span class="nlm-surname">Guo</span></span></span></div>
  
    	<div class="highwire-cite-metadata"><span  class="highwire-cite-metadata-journal highwire-cite-metadata">American Journal of Neuroradiology </span><span  class="highwire-cite-metadata-date highwire-cite-metadata">May 2010, </span><span  class="highwire-cite-metadata-volume highwire-cite-metadata">31 </span><span  class="highwire-cite-metadata-issue highwire-cite-metadata">(5) </span><span  class="highwire-cite-metadata-pages highwire-cite-metadata">838-843; </span><span  class="highwire-cite-metadata-doi highwire-cite-metadata"><span class="label">DOI:</span> 10.3174/ajnr.A1941 </span></div>
  
  
  
</div>
</div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-article-clipboard-copy large-margin-bottom" >
  
      
  
  <div class="pane-content">
    <div class = "clipboard-copy">
  <span class="label-url">
    <label for="dynamic">Share This Article:</label>
  </span>
  <span class="input-text-url">
    <input type="text" id="dynamic" value="http://ajnr-stage2.stage.highwire.org/content/31/5/838" size="50"/>
  </span>
  <span class="copy-button button">
    <button id="copy-dynamic" class="clipboardjs-button" data-clipboard-target="#dynamic" data-clipboard-alert-style="tooltip" data-clipboard-alert-text="Copied!">Copy</button>
  </span>
</div>
  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-service-links" >
  
      
  
  <div class="pane-content">
    <div class="service-links"><a href="http://del.icio.us/post?url=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;title=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images" id="delicious" title="Bookmark this post on del.icio.us" class="service-links-delicious" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><img src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/highwire/highwire/images/delicious-32.png" alt="del.icio.us logo" /></a> <a href="http://twitter.com/share?url=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;text=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images" id="twitter" title="Share this on Twitter" class="service-links-twitter" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><img src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/highwire/highwire/images/twitter.png" alt="Twitter logo" /></a> <a href="http://www.facebook.com/sharer.php?u=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;t=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images" id="facebook" title="Share on Facebook" class="service-links-facebook" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><img src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/highwire/highwire/images/fb-blue.png" alt="Facebook logo" /></a> <a href="http://www.mendeley.com/import/?url=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;title=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images" id="mendeley" title="Share on Mendeley" class="service-links-mendeley" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><img src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/highwire/highwire/images/mendeley.png" alt="Mendeley logo" /></a></div>  </div>

  
  </div>
</div>
  </div>
</div>
  </div>

  
  </div>
<div class="panel-pane pane-service-links" >
  
      
  
  <div class="pane-content">
    <div class="service-links"><div class="item-list"><ul><li class="first"><a href="http://twitter.com/share?url=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;count=horizontal&amp;via=&amp;text=Revisiting%20Anterior%20Atlantoaxial%20Subluxation%20with%20Overlooked%20Information%20on%20MR%20Images&amp;counturl=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838" class="twitter-share-button service-links-twitter-widget" id="twitter_widget" title="Tweet This" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><span class="element-invisible">Tweet Widget</span></a></li><li><a href="http://www.facebook.com/plugins/like.php?href=http%3A//ajnr-stage2.stage.highwire.org/content/31/5/838&amp;layout=button_count&amp;show_faces=false&amp;action=like&amp;colorscheme=light&amp;width=100&amp;height=21&amp;font=&amp;locale=" id="facebook_like" title="I Like it" class="service-links-facebook-like" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><span class="element-invisible">Facebook Like</span></a></li><li class="last"><a href="http://ajnr-stage2.stage.highwire.org/content/31/5/838" id="google_plus_one" title="Plus it" class="service-links-google-plus-one" rel="nofollow" target="_blank" data-icon-position="" data-hide-link-title="0"><span class="element-invisible">Google Plus One</span></a></li></ul></div></div>  </div>

  
  </div>
</div>
          </div>
        </div>
	</div> <!-- /.panel-row-wrapper -->	
	
	</div>

  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-jnl-ajnr-rental" >
  
      
  
  <div class="pane-content">
    <span class="js-deepdyve-link">
            <a class="button btn btn-primary btn-sm" role="button"  href="https://www.deepdyve.com/doc-view?docId=10.3174/ajnr.A1941&fieldName=journal_doi&affiliateId=asnr"><i class="icon-usd"> </i> Purchase</a>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-article-nav mobile-hidden pane-style-alt-content" >
  
        <h2 class="pane-title">Jump to section</h2>
    
  
  <div class="pane-content">
    <div class="highwire-list-wrapper highwire-article-nav highwire-nav-float"><div class="highwire-list"><ul data-highwire-float="1" data-highwire-float-class="grid-10 alpha omega"><li class="parent first odd"><a href="/content/31/5/838" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-is-tab-link="true" data-icon-position="" data-hide-link-title="0">Article</a><div class="highwire-list"><ul><li class="first odd"><a href="#abstract-1" class="highwire-article-nav-jumplink first" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Abstract</a></li><li class="even"><a href="#glossary-1" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Abbreviations</a></li><li class="odd"><a href="#sec-5" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Materials and Methods</a></li><li class="even"><a href="#sec-10" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Results</a></li><li class="odd"><a href="#sec-11" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Discussion</a></li><li class="even"><a href="#sec-12" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Conclusions</a></li><li class="odd"><a href="#fn-group-1" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">Footnotes</a></li><li class="last even"><a href="#ref-list-1" class="highwire-article-nav-jumplink last" data-panel-ajax-tab="jnl_ajnr_tab_art" data-icon-position="" data-hide-link-title="0">References</a></li></ul></div></li><li class="even"><a href="/content/31/5/838/tab-figures-data" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_data" data-is-tab-link="true" data-icon-position="" data-hide-link-title="0">Figures &amp; Data</a></li><li class="odd"><a href="/content/31/5/838/tab-references" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_refs" data-is-tab-link="true" data-icon-position="" data-hide-link-title="0">References</a></li><li class="even"><a href="/content/31/5/838/tab-article-info" class="highwire-article-nav-jumplink" data-panel-ajax-tab="jnl_ajnr_tab_info" data-is-tab-link="true" data-icon-position="" data-hide-link-title="0">Info &amp; Metrics</a></li><li class="last odd"><a href="/content/31/5/838.full.pdf" class="highwire-article-nav-jumplink" data-icon-position="" data-hide-link-title="0"><i class="icon-file-alt"></i> PDF</a></li></ul></div></div>  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-panels-mini pane-jnl-ajnr-accordion" >
  
      
  
  <div class="pane-content">
    <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_accordion">
  <div class="panel-panel panel-col">
    <div><div id="highwire_article_accordion_container"><h3 ><i class="icon-caret-right"></i> Related Articles</h3><div><div class="highwire-list highwire-related-articles highwire-article-citation-list"><ul class="highwire-related-articles-list"><li class="first last odd"><div class="no-results">No related articles found.</div></li></ul></div><div class='highwire-list-footer'><div class="highwire-related-articles-footer"><ul class="links inline"><li class="related-pubmed first"><a href="/lookup/external-ref?link_type=MED_NBRS&amp;access_num=20044504" target="_blank" class="" data-icon-position="" data-hide-link-title="0">PubMed</a></li><li class="related-google-scholar last"><a href="/lookup/google-scholar?link_type=googlescholar&amp;gs_type=related&amp;author%5B0%5D=S.-C.%2BHung&amp;author%5B1%5D=H.-M.%2BWu&amp;author%5B2%5D=W.-Y.%2BGuo&amp;title=Revisiting%2BAnterior%2BAtlantoaxial%2BSubluxation%2Bwith%2BOverlooked%2BInformation%2Bon%2BMR%2BImages&amp;publication_year=2010&amp;path=content/31/5/838" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Google Scholar</a></li></ul></div></div></div><h3 ><i class="icon-caret-right"></i> Cited By...</h3><div><div class="highwire-list highwire-cited-by"><ul><li class="first last odd"><a href="http://www.bjj.boneandjoint.org.uk/cgi/content/full/98-B/5/715" class="" data-icon-position="" data-hide-link-title="0"><div class="highwire-cite-title">The delayed presentation of atlantoaxial rotatory fixation in children: a review of the management</div></a><div class="variant-links"></div></li></ul></div><div class='highwire-list-footer'><ul class="links inline"><li class="citing-cross-ref first"><a href="/crossref-forward-links/ajnr/31/5/838#crossref" class="hw-crossref hw-crossref-link-ajax" data-list-wrapper="hw-crossref-list-wrapper" target="_blank" data-icon-position="" data-hide-link-title="0">Crossref</a></li><li class="citing-google-scholar last"><a href="/lookup/google-scholar?link_type=googlescholar&amp;gs_type=citedby&amp;path=content/31/5/838" target="_blank" class="" data-icon-position="" data-hide-link-title="0">Google Scholar</a></li></ul></div><div title="Crossref Cited-by Linking Search Results" style="display:none;" class="hw-crossref-list-wrapper"><p class = "hw-crossref-message">This article has not yet been cited by articles in journals that are participating in Crossref Cited-by Linking.</p></div></div><h3 ><i class="icon-caret-right"></i> More in this TOC Section</h3><div><div class="highwire-list highwire-article-citation-list"><ul><li class="first odd"><div class="highwire-article-citation highwire-citation-type-highwire-article node103857" data-node-nid="103857" id="node-103857--21836794172" data-pisa="ajnr;44/9/1101" data-pisa-master="ajnr;ajnr.A7964" data-apath="/ajnr/44/9/1101.atom"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-standard-title-only clearfix">
  
  
  
  
      <a href="/content/44/9/1101" class="highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title">Contribution of the MP2RAGE 7T Sequence in MS Lesions of the Cervical Spinal Cord</span></a>  
  
  
  
  
</div>
</div></li><li class="even"><div class="highwire-article-citation highwire-citation-type-highwire-article node103851" data-node-nid="103851" id="node-103851--2146133225" data-pisa="ajnr;44/9/1096" data-pisa-master="ajnr;ajnr.A7962" data-apath="/ajnr/44/9/1096.atom"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-standard-title-only clearfix">
  
  
  
  
      <a href="/content/44/9/1096" class="highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title">Validity of the Bern Score as a Surrogate Marker of Clinical Severity in Patients with Spontaneous Intracranial Hypotension</span></a>  
  
  
  
  
</div>
</div></li><li class="last odd"><div class="highwire-article-citation highwire-citation-type-highwire-article node103494" data-node-nid="103494" id="node-103494--21877857274" data-pisa="ajnr;44/8/994" data-pisa-master="ajnr;ajnr.A7927" data-apath="/ajnr/44/8/994.atom"><div class="highwire-cite highwire-cite-highwire-article highwire-citation-jcore-standard-title-only clearfix">
  
  
  
  
      <a href="/content/44/8/994" class="highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title">Resisted Inspiration Improves Visualization of CSF-Venous Fistulas in Spontaneous Intracranial Hypotension</span></a>  
  
  
  
  
</div>
</div></li></ul></div><div class='highwire-list-footer'><a href="/content/by/section/Spine" class="" data-icon-position="" data-hide-link-title="0">Show more <span class="wrapper">SPINE</span></a></div></div><h3 ><i class="icon-caret-right"></i> Similar Articles</h3><div><div class="highwire-search-similar-ajax-wrapper" id="highwire-search-similar-articles-list-1"><div class="highwire-ajax-loading"><span class="icon-spinner icon-spin icon-2x"></span></div></div></div></div></div>
  </div>
</div>
  </div>

  
  </div>
</div>
			</div>
		</div>
	
	</div> <!-- /.panel-row-wrapper -->	
	
	</div>

    </div>
  </div>
</div><div class="block block-panels-mini more-padding-top mobile-hiddens block-jnl-ajnr-ad-bot-leaderboard block-panels-mini-jnl-ajnr-ad-bot-leaderboard even block-without-title" id="block-panels-mini-jnl-ajnr-ad-bot-leaderboard">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_ad_bot_leaderboard">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-dfp-pane text-center" >
  
      
  
  <div class="pane-content">
    <div id="dfp-ad-bottom_leaderboard-wrapper" class="dfp-tag-wrapper">
<div class="slug">Advertisement</div>
<div  id="dfp-ad-bottom_leaderboard" class="dfp-tag-wrapper">
  <script type="text/javascript">
    googletag.cmd.push(function() {
      googletag.display("dfp-ad-bottom_leaderboard");
    });
  </script>
</div>
</div>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>      </div>
</div>  </div>
</section>    
  
      <footer id="section-footer" class="section section-footer">
    
  <div id="zone-postscript" class="zone zone-postscript clearfix container-30">
    <div class="grid-28 suffix-1 prefix-1 region region-postscript-fourth" id="region-postscript-fourth">
  <div class="region-inner region-postscript-fourth-inner">
    <div class="block block-panels-mini block-jnl-ajnr-footer block-panels-mini-jnl-ajnr-footer odd block-without-title" id="block-panels-mini-jnl-ajnr-footer">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panels-960-row jcore-row-4col clearfix" id="mini-panel-jnl_ajnr_footer">
  <div class="panel-panel panel-region-col-1 grid-7 alpha">
    <div class="inside"><div class="panel-pane pane-block pane-menu-navigate pane-menu" >
  
        <h2 class="pane-title">News and Updates</h2>
    
  
  <div class="pane-content">
    <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf" role="menuitem"><a href="https://www.ajnr.org/cc/2024-Awards" data-hide-link-title="0" class="" data-icon-position="">2024 Journal Award Winners</a></li>
<li class="last leaf" role="menuitem"><a href="/page/content/Reviewer-Recognition" data-hide-link-title="0" class="" data-icon-position="">Thanks to our 2023 Distinguished Reviewers</a></li>
</ul></nav>  </div>

  
  </div>
</div>
  </div>
  <div class="panel-panel panel-region-col-2 grid-7">
    <div class="inside"><div class="panel-pane pane-block pane-menu-more-information pane-menu" >
  
        <h2 class="pane-title">Resources</h2>
    
  
  <div class="pane-content">
    <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf" role="menuitem"><a href="/page/content/EBM" data-hide-link-title="0" class="" data-icon-position="">Evidence-Based Medicine Level Guide</a></li>
<li class="leaf" role="menuitem"><a href="/content/browse-podcast-archives" data-hide-link-title="0" class="" data-icon-position="">AJNR Podcast Archive</a></li>
<li class="leaf" role="menuitem"><a href="/content/institutional-subscriptions" data-hide-link-title="0" class="" data-icon-position="">Librarian Resources</a></li>
<li class="last leaf" role="menuitem"><a href="http://www.ajnr.org/page/content/Terms-and-Conditions" data-hide-link-title="0" class="" data-icon-position="">Terms and Conditions</a></li>
</ul></nav>  </div>

  
  </div>
</div>
  </div>
  <div class="panel-panel panel-region-col-3 grid-7">
    <div class="inside"><div class="panel-pane pane-block pane-menu-add-journals pane-menu" >
  
        <h2 class="pane-title">Opportunities</h2>
    
  
  <div class="pane-content">
    <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first last leaf" role="menuitem"><a href="/page/content/Publons" data-hide-link-title="0" class="" data-icon-position="">Get Peer Review Credit from Publons</a></li>
</ul></nav>  </div>

  
  </div>
</div>
  </div>
  <div class="panel-panel panel-region-col-4 grid-7 omega">
    <div class="inside"><div class="panel-pane pane-block pane-menu-other-services pane-menu" >
  
        <h2 class="pane-title">American Society of Neuroradiology</h2>
    
  
  <div class="pane-content">
    <nav class="menubar-nav"><ul class="menu" role="menu"><li class="first leaf" role="menuitem"><a href="http://www.neurographics.org/" data-hide-link-title="0" class="" data-icon-position="">Neurographics</a></li>
<li class="leaf" role="menuitem"><a href="http://www.asnr.org/index.php/education/fellowship-portal/" data-hide-link-title="0" class="" data-icon-position="">Fellowship Portal</a></li>
<li class="last leaf" role="menuitem"><a href="https://www.asnr.org/membership-types/" data-hide-link-title="0" class="" data-icon-position="">Not an ASNR Member? Join Now</a></li>
</ul></nav>  </div>

  
  </div>
</div>
  </div>
</div>    </div>
  </div>
</div>  </div>
</div>  </div>
  
  <div id="zone-footer" class="zone zone-footer clearfix container-30">
    <div class="grid-28 suffix-1 prefix-1 region region-footer-first" id="region-footer-first">
  <div class="region-inner region-footer-first-inner">
    <div class="block block-panels-mini block-jnl-ajnr-foot-info block-panels-mini-jnl-ajnr-foot-info odd block-without-title" id="block-panels-mini-jnl-ajnr-foot-info">
  <div class="block-inner clearfix">
                
    <div class="content clearfix">
      <div class="panel-display panel-1col clearfix" id="mini-panel-jnl_ajnr_foot_info">
  <div class="panel-panel panel-col">
    <div><div class="panel-pane pane-page-logo-footer" >
  
      
  
  <div class="pane-content">
    <img class="footer-logo" src="http://ajnr-stage2.stage.highwire.org/sites/default/files/ajnr-logo.png" alt="" />  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-snippet pane-footer-copyright-text" >
  
      
  
  <div class="pane-content">
    <div class="snippet footer-copyright-text" id="footer-copyright-text">
  
      
  <div class="snippet-content">
    <p>&copy; 2025 by the <a href="http://www.asnr.org">American Society of Neuroradiology</a> All rights, including for text and data mining, AI training, and similar technologies, are reserved.<br />
Print ISSN: 0195-6108 Online ISSN: 1936-959X</p>
  </div>

</div>
  </div>

  
  </div>
<div class="panel-separator"></div><div class="panel-pane pane-highwire-branding" >
  
      
  
  <div class="pane-content">
    <a href="http://home.highwire.org" target="_blank" class="highwire-branding-link" data-icon-position="" data-hide-link-title="0"><img class="logo-highwire" src="http://ajnr-stage2.stage.highwire.org/sites/all/modules/highwire/highwire/plugins/content_types/images/logo_small_hw_white.png" width="190" height="31" alt="Powered by HighWire" /></a>  </div>

  
  </div>
</div>
  </div>
</div>
    </div>
  </div>
</div>  </div>
</div>  </div>
</footer>  </div>    <div class="region region-page-bottom" id="region-page-bottom">
  <div class="region-inner region-page-bottom-inner">
      </div>
</div><script type="text/javascript" src="/sites/default/files/advagg_js/js__bnwyEQSuZLC-kZnFqCi5iE02nOCzM7DjY7zYxcN9nsQ__VBiBT_qq_eHMMO2Q1rXK1u-hHff31XLUkmi9dgjuPeY__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__GM3GJPR36rRIz0TRkjC5OQwrioSyN9aoYRivDhCO_AM__qAl84FcCv2jyN22yFGS5Oc85cjd9zKX6p_cFNLGhe-M__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js" async="async"></script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__puuQ6qZuZflSOzhCnY-jgY7Fv9AlRwAQ8SzEc4pSqOs__QdvWVdmkPpxtURk1sK0nHm-KZ4OJQjVuYZTnLqK1Isw__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
function euCookieComplianceLoadScripts() {}
//--><!]]>
</script>
<script type="text/javascript">
<!--//--><![CDATA[//><!--
var eu_cookie_compliance_cookie_name = "";
//--><!]]>
</script>
<script type="text/javascript" src="/sites/default/files/advagg_js/js__WcTpt-w0y1FyXrxZNriX8Ts1KjsFTDpdvZaw9yhRn24__aFJpdvsZPb1v9rWrq-WXbz_WQ9IThQN-mFTCdm1cfXc__Op4k-kV4DoWc7bsUP7umKmZ0WXfmoYdRDoZFPNSd-oM.js"></script>
  </body>
</html>