Qiang Shen1,2, Shiliang Huang1,
Fang Du1, Timothy Q. Duong1,2
1Research Imaging Institute, University
of Texas Health Science Center at San Antonio, San Antonio, TX, United
States; 2Department of Ophthalmology/Radiology, University of
Texas Health Science Center at San Antonio, San Antonio, TX, United States
The
identification of ischemic penumbra is of utmost importance for the
initiation of treatment strategies. Although diffusion/perfusion MRI mismatch
has been used to be an estimate of penumbra, it has been demonstrated
overestimation of penumbra. Beside perfusion deficit, a marker of metabolism
is essential to better define penumbra. In this study, the spatial and
temporal responses of stroke rats to 100% oxygen challenge were investigated.
DWI/PWI mismatch region showed significant higher than normal T2*-weighted
signal increase. Tissue with higher than normal T2*-weighted signal increase
during OC and spatially around the ischemic core could be a better estimation
of penumbra.