Typical Coloboma in the Eye of a CD Rat

Abstract

Coloboma was found in the left eye of a female Crj: (CD) SD rat. Ophthalmoscopic examination revealed focal defect of the iris, which was oval in shape and located at the inferionasal aspect. Ophthalmoscopic findings of the fundus included large and dark optic disc, tortuous and irregularly oriented retinal vessels, and a pale focus located inferionasally to the optic disc. There was also an oval and ill-defined opaque on the posterior lens capsule extending from the posterior pole toward inferionasal aspect. Histopathologically, the pale fundic lesion was characterized by focal retinal thinning and retinal fold associated with focal defect of the choroid. The lenticular opaque lesion consisted of persistent tunica vasculosa lentis.