Congenital retinal folds in Sheffield-Wistar rats.

Retinal folds are described in male rats of a Wistar-derived strain, which occasionally shows microphthalmia and cataract. The less severe lesions mainly affect the outer retinal layers and contain microretinal detachment, cell rosettes, phagocytic cells and lipid debris. More severe folds involve all the retinal layers, exhibit subretinal haemorrhage, and photoreceptor outer segment debris throughout the lesion and on the vitreal surface. The lesions are discussed in relation to previous observations of retinal folds.