[Roundish crystal formations in the retina and vitreous body (calcium oxalate and scintillatio nivea)].

Crystals of calcium oxalate in the outer layers of the retina are usually found in blind eyes with long-standing retinal detachment. The crystals are strongly birefringent, mostly radially arranged, and round. In asteroid hyalosis - the scintillatio nivea of the vitreous - the crystals are always closely related to vitreous fibrils or the limiting membrane. The birefringent bodies are apparently formed and initially often covered by vitreous cells (hyalocytes). The birefringence corresponds to that of brushite (Ca HPO4 X 2 H2O).