Audrey Peiwen Fan1, Thomas Benner2,
Divya S. Bolar3, Bruce R. Rosen2,3, Elfar
Adalsteinsson, 1,3
1Electrical Engineering and Computer
Science, MIT, Cambridge, MA, United States; 2Athinoula A. Martinos
Center for Biomedical Imaging, Charlestown, MA, United States; 3Health
Sciences and Technology, Harvard-MIT, Cambridge, MA, United States
The
cerebral metabolic rate of oxygen (CMRO2) is an important indicator for brain
function and disease, including stroke and tumor. CMRO2 can be quantified from measurements
of venous oxygen saturation (Yv) and cerebral blood flow (CBF) in cerebral
veins. Bulk susceptibility
measurements based on gradient-echo phase maps has been used to estimate Yv
in vivo at 3T. Challenges of this technique include partial volume effects,
phase wrapping, and background susceptibility gradients. Here we combine phase-based measurements of
Yv with ASL measurements of CBF to quantify CMRO2 in cerebral vessels at
3T. Further, we extended estimates of
Yv to 7T, achieving a 1/5 reduction in voxel size. The improved spatial resolution allows
examination of smaller vessels more indicative of regional brain
function. Future work includes
extending the method to estimate CMRO2 at 7T.