The histopathology of Peters' anomaly.

Corneal, iris, and trabecular meshwork tissue in a 23-month-old boy with Peters' anomaly were studied with light and electron microscopy. In the cornea, both Descemet's membrane and endothelium were present beneath the area of the corneal opacity except at the point of iris adhesion. However, Descemet's membrane was thin and embryonal in nature, and the endothelium markedly attenuated. The trabecular meshwork demonstrated changes characteristic of old age such as wide-banded collagen and the presence of phagocytosed pigment granules in the endothelium. The iris appeared normal except for anterior synechiae to the corneal opacity. Developmentally, the primary fault appeared to be a failure in the normal differentiation of endothelial cells of the cornea and trabecular meshwork.