Experimental Embolic Ischemia of the Choroid

Abstract

A latex microsphere suspension was injected into a vortex vein of 23 cat eyes producing a large sector of ischemia of the choroid extending from the ciliary body to the posterior pole without similar effect on the retinal vessels. Initially, multiple white spots appeared in the ischemic sector of the fundus followed, in 14 eyes, by a detachment of the retina. On microscopic examination, there was a sharply demarcated loss of the external layers of the retina and a loss of the normal pattern of the pigment epithelium which correlated with depigmentation of the fundus in the ischemic sector. In nine eyes the pigment epithelium migrated into the retina without relation to the retinal vessels. Multiple cystoid changes occurred on the pars plana but not in the retina. These cysts contained a hyaluronidase-sensitive material.