Guang Li1,
Jeffrey W. Kiel2, Damon P. Cardenas3, De La Garza H.
Bryan4, Timothy O. Duong4
1Department
of Radiology, UT Health Science Center at San Antonio, San Antonio, TX,
United States; 2Department of Ophthalmology, UT Health Science
Center at San Antonio, San Antonio, TX, United States; 3Department
of Biomedical Engineering, UT Health Science Center at San Antonio, San
Antonio, TX, United States; 4Research Imaging Institute, UT Health
Science Center at San Antonio, San Antonio, TX, United States
While post-occlusion reactive hyperemia has been attributed to metabolic local control (matching of blood flow (BF) to local metabolic demands) in various tissues, post-occlusion reactive hyperemia in the retina has not yet been studied. We found differential BOLD and BF responses in the retinal and choroidal circulations in the retina during and immediately after transient carotid occlusion. Reactive hyperemia was detected in the retina but not in the choroid, suggesting that the retinal circulation is under metabolic local control but the choroid is not. These findings provide novel insights in the hemodynamic regulation of the retinal and the choroidal circulations.