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<meta name="DC.Title" content="Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations" />
<meta name="DC.Identifier" content="10.3174/ajnr.A2948" />
<meta name="DC.Date" content="2012-08-01" />
<meta name="DC.Publisher" content="American Journal of Neuroradiology" />
<meta name="DC.Rights" content="© 2012 by American Journal of Neuroradiology" />
<meta name="DC.AccessRights" content="restricted" />
<meta name="DC.Description" content="BACKGROUND AND PURPOSE: Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I.

MATERIALS AND METHODS: Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as R 2. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis.

RESULTS: Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean R 2 equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group ( P = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups ( P = .60 and 0.76, respectively).

CONCLUSIONS: Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls.

HDCT
:   hereditary disorders of connective tissue
IQR
:   interquartile range
IS
:   idiopathic syringomyelia
SE
:   standard error" />
<meta name="DC.Contributor" content="M. Hirano" />
<meta name="DC.Contributor" content="V. Haughton" />
<meta name="DC.Contributor" content="A. Munoz del Rio" />
<meta name="article:published_time" content="2012-08-01" />
<meta name="article:section" content="Spine" />
<meta name="citation_title" content="Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations" />
<meta name="citation_abstract" lang="en" content="&lt;h3&gt;BACKGROUND AND PURPOSE:&lt;/h3&gt;
&lt;p&gt;Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I.&lt;/p&gt;&lt;h3&gt;MATERIALS AND METHODS:&lt;/h3&gt;
&lt;p&gt;Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as &lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt;. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis.&lt;/p&gt;&lt;h3&gt;RESULTS:&lt;/h3&gt;
&lt;p&gt;Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean &lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group (&lt;i&gt;P&lt;/i&gt; = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups (&lt;i&gt;P&lt;/i&gt; = .60 and 0.76, respectively).&lt;/p&gt;&lt;h3&gt;CONCLUSIONS:&lt;/h3&gt;
&lt;p&gt;Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls.&lt;/p&gt;" />
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<meta name="twitter:title" content="Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations" />
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<meta name="twitter:description" content="BACKGROUND AND PURPOSE: Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I.

MATERIALS AND METHODS: Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as R 2. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis.

RESULTS: Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean R 2 equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group ( P = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups ( P = .60 and 0.76, respectively).

CONCLUSIONS: Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls.

HDCT
:   hereditary disorders of connective tissue
IQR
:   interquartile range
IS
:   idiopathic syringomyelia
SE
:   standard error" />
<meta name="og-title" property="og:title" content="Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations" />
<meta name="og-url" property="og:url" content="http://ajnr-stage2.stage.highwire.org/content/33/7/1326" />
<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: Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I.

MATERIALS AND METHODS: Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as R 2. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis.

RESULTS: Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean R 2 equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group ( P = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups ( P = .60 and 0.76, respectively).

CONCLUSIONS: Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls.

HDCT
:   hereditary disorders of connective tissue
IQR
:   interquartile range
IS
:   idiopathic syringomyelia
SE
:   standard error" />
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      <h1 class="highwire-cite-title" id="page-title">Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations</h1>  
    	<div class="highwire-cite-authors"><span  class="highwire-citation-authors"><span class="highwire-citation-author first" data-delta="0">M. Hirano</span>, <span class="highwire-citation-author" data-delta="1">V. Haughton</span> and <span class="highwire-citation-author" data-delta="2">A. Munoz del Rio</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">August 2012,  </span><span  class="highwire-cite-metadata-volume highwire-cite-metadata">33 </span><span  class="highwire-cite-metadata-issue highwire-cite-metadata">(7) </span><span  class="highwire-cite-metadata-pages highwire-cite-metadata">1326-1330; </span><span  class="highwire-cite-metadata-doi highwire-cite-metadata">DOI: https://doi.org/10.3174/ajnr.A2948 </span></div>
  
  
  
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<div id="hw-article-author-popups-top-node-12013--61282255108" style="display: none;"><div class="author-tooltip-0"><div class="author-tooltip-name">M. Hirano </div><div class="author-tooltip-affiliation"><span class="author-tooltip-text"><div class='author-affiliation'>aFrom the University of Wisconsin (M.H.), Madison, Wisconsin</div></span></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=M.%2BHirano%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=Hirano%20M&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%3AM.%2BHirano%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">V. Haughton </div><div class="author-tooltip-affiliation"><span class="author-tooltip-text"><div class='author-affiliation'>bDepartments of Radiology (V.H., A.M.) and Medical Physics (A.M.), University of Wisconsin School of Medicine and Public Health, Madison Wisconsin.</div></span></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=V.%2BHaughton%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=Haughton%20V&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%3AV.%2BHaughton%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">A. Munoz del Rio </div><div class="author-tooltip-affiliation"><span class="author-tooltip-text"><div class='author-affiliation'>bDepartments of Radiology (V.H., A.M.) and Medical Physics (A.M.), University of Wisconsin School of Medicine and Public Health, Madison Wisconsin.</div></span></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=A.%2BMunoz%2Bdel%2BRio%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=Munoz%20del%20Rio%20A&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%3AA.%2BMunoz%2Bdel%2BRio%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>

  
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<div id="sec-1" class="subsection">
 
<p id="p-1"><strong>BACKGROUND AND PURPOSE:</strong> Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I.</p>
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<p id="p-2"><strong>MATERIALS AND METHODS:</strong> Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as <em>R</em><sup>2</sup>. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis.</p>
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<p id="p-3"><strong>RESULTS:</strong> Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean <em>R</em><sup>2</sup> equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group (<em>P</em> = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups (<em>P</em> = .60 and 0.76, respectively).</p>
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<p id="p-4"><strong>CONCLUSIONS:</strong> Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls.</p>
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<h2>ABBREVIATIONS:</h2>
<dl id="def-list-1"><dt id="def-item-1">HDCT<span class="def-item-dt-sep"></span></dt><dd>hereditary disorders of connective tissue<span class="def-item-dd-sep"></span></dd><dt id="def-item-2">IQR<span class="def-item-dt-sep"></span></dt><dd>interquartile range<span class="def-item-dd-sep"></span></dd><dt id="def-item-3">IS<span class="def-item-dt-sep"></span></dt><dd>idiopathic syringomyelia<span class="def-item-dd-sep"></span></dd><dt id="def-item-4">SE<span class="def-item-dt-sep"></span></dt><dd>standard error</dd></dl></div><ul class="copyright-statement"><li class="fn" id="copyright-statement-1">© 2012 by American Journal 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/33/7/1326.full" class="hw-link hw-link-article-full-text" data-icon-position="" data-hide-link-title="0">View Full Text</a></div>  </div>

  
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    	<div class="highwire-cite-authors"><span  class="highwire-citation-authors"><span class="highwire-citation-author first" data-delta="0"><span class="nlm-given-names">M.</span> <span class="nlm-surname">Hirano</span></span>, <span class="highwire-citation-author" data-delta="1"><span class="nlm-given-names">V.</span> <span class="nlm-surname">Haughton</span></span>, <span class="highwire-citation-author" data-delta="2"><span class="nlm-given-names">A.</span> <span class="nlm-surname">Munoz del Rio</span></span></span></div>
  
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