[Retrolental cloudiness of the vitreous humor in the rat eye].

Small globular vitreous opacities were observed by routine slit lamp eye examinations in aged Sprague-Dawley rats. This finding occurs first in about 5% of the animals at the age of 58-89 weeks. In rats 101-134 weeks old, the incidence of this finding increases up to approximately 20%. Wistar rats show these vitreous opacities only rarely; and if so, they occur at the age of at least 101-134 weeks. The histological examinations revealed retrolental protein globules without any inflammatory response which probably consist of lens cortex material. The lenses showed a fragmentation with small gaps of the capsule at the posterior pole as well as posterior sutural cataracts. We believed that strain and age dependent degenerative changes of the posterior lens capsule are the cause of the extrusion of lens protein into the vitreous.