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PT  - JOURNAL ARTICLE
AU  - Nael, K.
AU  - Mossadeghi, B.
AU  - Boutelier, T.
AU  - Kubal, W.
AU  - Krupinski, E.A.
AU  - Dagher, J.
AU  - Villablanca, J.P.
TI  - Bayesian Estimation of Cerebral Perfusion Using Reduced-Contrast-Dose Dynamic Susceptibility Contrast Perfusion at 3T
AID  - 10.3174/ajnr.A4184
DP  - 2015 Apr 01
TA  - American Journal of Neuroradiology
PG  - 710--718
VI  - 36
IP  - 4
4099  - http://www.ajnr.org/content/36/4/710.short
4100  - http://www.ajnr.org/content/36/4/710.full
SO  - Am. J. Neuroradiol.2015 Apr 01; 36
AB  - BACKGROUND AND PURPOSE: DSC perfusion has been increasingly used in conjunction with other contrast-enhanced MR applications and therefore there is need for contrast-dose reduction when feasible. The purpose of this study was to establish the feasibility of reduced-contrast-dose brain DSC perfusion by using a probabilistic Bayesian method and to compare the results with the commonly used singular value decomposition technique. MATERIALS AND METHODS: Half-dose (0.05-mmol/kg) and full-dose (0.1-mmol/kg) DSC perfusion studies were prospectively performed in 20 patients (12 men; 34–70 years of age) by using a 3T MR imaging scanner and a gradient-EPI sequence (TR/TE, 1450/22 ms; flip angle, 90°). All DSC scans were processed with block circulant singular value decomposition and Bayesian probabilistic methods. SNR analysis was performed in both half-dose and full-dose groups. The CBF, CBV, and MTT maps from both full-dose and half-dose scans were evaluated qualitatively and quantitatively in both WM and GM on coregistered perfusion maps. Statistical analysis was performed by using a t test, regression, and Bland-Altman analysis. RESULTS: The SNR was significantly (P &amp;lt; .0001) lower in the half-dose group with 32% and 40% reduction in GM and WM, respectively. In the half-dose group, the image-quality scores were significantly higher in Bayesian-derived CBV (P = .02) and MTT (P = .004) maps in comparison with block circulant singular value decomposition. Quantitative values of CBF, CBV, and MTT in Bayesian-processed data were comparable and without a statistically significant difference between the half-dose and full-dose groups. The block circulant singular value decomposition–derived half-dose perfusion values were significantly different from those of the full-dose group both in GM (CBF, P &amp;lt; .001; CBV, P = .02; MTT, P = .02) and WM (CBF, P &amp;lt; .001; CBV, P = .003; MTT, P = .01). CONCLUSIONS: Reduced-contrast-dose (0.05-mmol/kg) DSC perfusion of the brain is feasible at 3T by using the Bayesian probabilistic method with quantitative results comparable with those of the full-dose protocol. cSVDblock circulant singular value decompositionFDfull-doseHDhalf-doseSVDsingular value decomposition