1naresh<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
                )

        )

)
1naresh<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] => OpenAccess
            [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
                )

        )

)
PT  - JOURNAL ARTICLE
AU  - Schmainda, K.M.
AU  - Prah, M.A.
AU  - Hu, L.S.
AU  - Quarles, C.C.
AU  - Semmineh, N.
AU  - Rand, S.D.
AU  - Connelly, J.M.
AU  - Anderies, B.
AU  - Zhou, Y.
AU  - Liu, Y.
AU  - Logan, B.
AU  - Stokes, A.
AU  - Baird, G.
AU  - Boxerman, J.L.
TI  - Moving Toward a Consensus DSC-MRI Protocol: Validation of a Low–Flip Angle Single-Dose Option as a Reference Standard for Brain Tumors
AID  - 10.3174/ajnr.A6015
DP  - 2019 Apr 01
TA  - American Journal of Neuroradiology
PG  - 626--633
VI  - 40
IP  - 4
4099  - http://www.ajnr.org/content/40/4/626.short
4100  - http://www.ajnr.org/content/40/4/626.full
SO  - Am. J. Neuroradiol.2019 Apr 01; 40
AB  - BACKGROUND AND PURPOSE: DSC-MR imaging using preload, intermediate (60°) flip angle and postprocessing leakage correction has gained traction as a standard methodology. Simulations suggest that DSC-MR imaging with flip angle = 30° and no preload yields relative CBV practically equivalent to the reference standard. This study tested this hypothesis in vivo.MATERIALS AND METHODS: Eighty-four patients with brain lesions were enrolled in this 3-institution study. Forty-three patients satisfied the inclusion criteria. DSC-MR imaging (3T, single-dose gadobutrol, gradient recalled-echo–EPI, TE = 20–35 ms, TR = 1.2–1.63 seconds) was performed twice for each patient, with flip angle = 30°–35° and no preload (P−), which provided preload (P+) for the subsequent intermediate flip angle = 60°. Normalized relative CBV and standardized relative CBV maps were generated, including postprocessing with contrast agent leakage correction (C+) and without (C−) contrast agent leakage correction. Contrast-enhancing lesion volume, mean relative CBV, and contrast-to-noise ratio obtained with 30°/P−/C−, 30°/P−/C+, and 60°/P+/C− were compared with 60°/P+/C+ using the Lin concordance correlation coefficient and Bland-Altman analysis. Equivalence between the 30°/P−/C+ and 60°/P+/C+ protocols and the temporal SNR for the 30°/P− and 60°/P+ DSC-MR imaging data was also determined.RESULTS: Compared with 60°/P+/C+, 30°/P−/C+ had closest mean standardized relative CBV (P = .61), highest Lin concordance correlation coefficient (0.96), and lowest Bland-Altman bias (μ = 1.89), compared with 30°/P−/C− (P = .02, Lin concordance correlation coefficient = 0.59, μ = 14.6) and 60°/P+/C− (P = .03, Lin concordance correlation coefficient = 0.88, μ = −10.1) with no statistical difference in contrast-to-noise ratios across protocols. The normalized relative CBV and standardized relative CBV were statistically equivalent at the 10% level using either the 30°/P−/C+ or 60°/P+/C+ protocols. Temporal SNR was not significantly different for 30°/P− and 60°/P+ (P = .06).CONCLUSIONS: Tumor relative CBV derived from low–flip angle, no-preload DSC-MR imaging with leakage correction is an attractive single-dose alternative to the higher dose reference standard.C−postprocessing without contrast agent leakage correctionC+postprocessing with contrast agent leakage correctionLCCCLin concordance correlation coefficientnRCBVnormalized relative CBVP−a preload of contrast agent was not administeredP+a preload of contrast agent was administeredrCBVrelative CBVsRCBVstandardized relative CBV