High b-Value and Ultra-High b-Value Diffusion Weighted MRI in Stroke

To explore the application value of high-b-value and ultra-high b-value DWI in noninvasive evaluation of ischemic infarctions. Prospective. Sixty-four patients with clinically diagnosed ischemic lesions based on symptoms and DWI. 3.0 T/T2-weighted fast spin-echo, fluid-attenuated inversion recovery, pre-contrast T1-weighted magnetization prepared rapid gradient echo sequence, multi-b-value trace DWI and q-space sampling sequences. Lesions were segmented on standard b-value DWI (SB-DWI, 1000 s/mm ), high b-value DWI (HB-DWI, 4000 s/mm ) and ultra-high b-value DWI (UB-DWI, 10,000 s/mm ), and cumulative segmented areas were the final abnormality volumes. Normal white matter (WM) areas were obtained after binarization of segmented brain. In 47 patients, fractional anisotropy (FA) and apparent diffusion coefficients (ADCs) at b values of 1000, 4000, and 10,000 s/mm were extracted from symmetrical WM masks and lesion masks of contralateral WM (CWM) and lesion-side WM (LWM). Wilcoxon matched-pairs signed-rank test and Pearson correlation analysis. Two-tailed P-values