Intravascular BOLD signal contribution to the fMRI ADC changes in the IVIM model regime
Jin T, Kim S, Zhao F, Wang P
University of Pittsburgh
At 9.4T, the functional ADC changes were measured for TE=16ms, 28ms, and 60ms using small diffusion weighting (b<200s/mm2). The observed ADC changes were highly dependent on the TE. For TE=28ms and 60ms, the ADC changes were small (<1%) and mainly located at the middle of the visual cortex, and were attributed to an increase in the arterial blood volume and flow. Much larger ADC changes (~2%) on both the middle and the surface of the cortex were observed for TE=16ms. These results indicated that an intravascular BOLD signal change can contribute to the functional ADC contrast, and the contribution can be significant if the IV signal change is large.