Premium
Modeling dynamic cerebral blood volume changes during brain activation on the basis of the blood‐nulled functional MRI signal
Author(s) -
W. Wu Changwei,
Liu HoLing,
Chen JyhHorng
Publication year - 2007
Publication title -
nmr in biomedicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.278
H-Index - 114
eISSN - 1099-1492
pISSN - 0952-3480
DOI - 10.1002/nbm.1116
Subject(s) - cerebral blood volume , cerebral blood flow , nuclear magnetic resonance , functional magnetic resonance imaging , magnetic resonance imaging , blood volume , blood flow , dynamic contrast enhanced mri , signal (programming language) , chemistry , nuclear medicine , neuroscience , physics , cardiology , computer science , medicine , biology , radiology , programming language
Abstract Recently, vascular space occupancy (VASO) based functional magnetic resonance imaging (fMRI) was proposed to detect dynamic cerebral blood volume (CBV) changes using the blood‐nulled non‐selective inversion recovery (NSIR) sequence. However, directly mapping the dynamic CBV change by the NSIR signal change is based on the assumption of slow water exchange (SWE) around the capillary regime without cerebral blood flow (CBF) effects. In the present study, a fast water exchange (FWE) model incorporating with flow effects was derived from the Bloch equations and implemented for the quantification of dynamic CBV changes using VASO‐fMRI during brain activation. Simulated results showed that only subtle differences in CBV changes estimated by these two models were observed on the basis of previously published VASO results. The influence of related physiological and biophysical factors within typical ranges was evaluated in steady‐state simulations. It was revealed that in the transient state the CBV curves could be delayed in comparison with measured NSIR curves owing to the imbalance between the inflowing and outflowing blood signals. Copyright © 2007 John Wiley & Sons, Ltd.