Functional Characterization of Retina and Optic Nerve after Acute Ocular Ischemia in Rats

PURPOSE. To functionally characterize the status of the rat retina and optic nerve after acute elevation of intraocular pressure (IOP) and to determine the dynamics of the pathologic changes in the ischemic retina and optic nerve. METHODS. Retinal ischemia was induced in rats by acutely increasing the IOP (110 mm Hg/60 minutes). Direct and indi-rect pupil light reflexes (PLRs) were recorded from the nonin-jured eye, and electroretinograms (flash and flicker ERG) were recorded from the injured and control eyes before and after surgery. Amplitudes and latencies were calculated for each recording session. RESULTS. Preoperative PLRratios (indirect/direct PLR) were 76.7 2.6 (mean SEM). Twenty-four hours after surgery the PLRratio was 15.2 12.8, 10 days after surgery, 11.6 9.8; 20 days after surgery, 26.5 8.0; and 28 days after surgery