Reduction of onset variability of event-related BOLD responses with Diffusion-weighted Spin-echo EPI
Wan Y, Wang J, Wai Y, Chu T, Kuan W, Liu H
Chang Gung University, Chang Gung Memorial Hospital
This study aimed to evaluate the temporal properties and variability of hemodynamic responses measured by the diffusion-weighted spin-echo (DWSE) BOLD-fMRI and compare with spin-echo (SE) and gradient-echo (GE) results. Six healthy volunteers participated in the study. Brief visual stimulations were applied in repeated single-trials for the DWSE50 (b=50 s/mm2), DWSE200 (b=200 s/mm2), SE and GE experiments. Statistically earlier onset times and remarkably smaller variance at the same CNR level (controlled by averaging different number of trials) were observed with the DWSE than the GE data, with SE performed in between. No significant difference was found between DWSE50 and DWSE200.