Magnetic Resonance Imaging Indicates Decreased Choroidal and Retinal Blood Flow in the DBA/2J Mouse Model of Glaucoma

PURPOSE. This study tests the hypothesis that reduced retinal and choroidal blood flow (BF) occur in the DBA/2J mouse model of glaucoma. METHODS. Quantitative BF magnetic resonance imaging (MRI) with a resolution of 42 x 42 x 400 mu m was performed on DBA/2J mice at 4, 6, and 9 months of age and C57BL/6 age-matched controls under isoflurane anesthesia. BF MRI images were acquired with echo-planar imaging using an arterial spin labeling technique and a custom-made eye coil at 7 Tesla. Automated profile analysis was performed to average layer-specific BF along the length of the retina and choroid. In separate experiments, servo-null micropressure measurements of iliac arterial pressure were performed in old mice of both strains. RESULTS. Choroidal BF was lower in DBA/2J mice than in age-matched C57BL/6 control mice at 4, 6, and 9 months of age (P < 0.01 for all age-matched groups). Retinal BF was lower in DBA/2J mice than in C57BL/6 mice at the 9-month time point (P < 0.01). Mean arterial pressure was not significantly different in aged C57BL/6 mice compared with aged DBA/2J mice. CONCLUSIONS. The reduced ocular blood flow in DBA/2J mice compared with C57BL/6 control mice suggests that ischemia or hypoxia should be considered as a possible contributing factor in the optic neuropathy in the DBA/2J mouse model of glaucoma. (Invest Ophthalmol Vis Sci. 2012;53:560-564) DOI: 10.1167/iovs.11-8429