Outer retina ischemic infarction--a newly recognized complication of cataract extraction and closed vitrectomy. Part 2. An animal model.

Intraocular pressure was artificially elevated above systolic blood pressure in 40 owl monkey eyes. Diffuse retinal whitening of the posterior pole and subsequent retinal pigment epithelial disruption were produced in nine of ten eyes with high pressure for 90 minutes or longer, but also in a few eyes with high pressure for a shorter duration. Fluorescein angiography and histologic examination demonstrated damage of the photoreceptors and retinal pigment epithelium with sparing of the inner retinal layers. This animal model duplicates the acute visual loss due to outer retinal infarction that sometimes occurs after closed vitrectomy or after continuous external ocular compression in preparation for surgery.