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.