1993 Volume 6 Issue 2 Pages 205-211
Focal chorioretinal atrophy observed in untreated Sprague-Dawley rats was clinically and histopathologically described. On ophthalmoscopical examination, the lesion consisted of discrete, hyperreflective, frequently rectangular foci with sharp margins. Petechial hemorrhages preceded to the development of these foci. No particular predilection sites were evident in the fundus. Histopathological characteristics on the perfusion-fixed eyes included: 1) the affected region was focal and well demarcated, 2) the retina in the lesion was devoid of the external layers, 3) in contrast, the internal retinal layers were unaffected, 4) abrupt disappearance of the underlying retinal pigment epithelium and choroid capillaries coincides with the retinal change, and 4) very little inflammatory cell response. These findings suggest that the primary defect may be either in the retinal pigment epithelium or choroid capillaries with subsequent retinal atrophy.
