Ultrastructure of human cataract in retinitis pigmentosa.

A second ultrastructural study of retinitis pigmentosa cataract showed differences from the previous case with respect to sex, age of cataract onset, age at time of cataract extraction, and mode of inheritance of retinitis pigmentosa. Furthermore, the cataract in the present study was limited clinically and preponderantly ultrastructurally to the posterior subcapsular area, which is typical of the location of cataracts associated with retinitis pigmentosa. The cataract was characterized by severe lens fiber disorganization, resulting in intricately distorted membrane configurations and varying cytoplasmic densities; however, "figure eight" configurations as noted in the other report were not observed. Aberrantly migrated epithelial cells were distributed unevenly in the posterior subcapsular zone. New capsular basement membrane, not mentioned in the other report, was conspicuous in our case. Thus, retinitis pigmentosa cataract may have diverse ultrastructural alterations.