Morphologic characteristics of posterior polymorphous dystrophy. A study of nine corneas and review of the literature.

Based on their own study of nine corneas with clinically documented posterior polymorphous dystrophy and a review of the literature, the authors describe the morphologic features of this entity. Study by phase contrast light microscopy and transmission and scanning electron microscopy found that changes were primarily in the endothelium and consisted of endothelial cell degeneration and loss with focal fibroblastic and epithelial-like cell transformation. Secondary alterations of Descemet's membrane were seen; they consisted of abnormal lamination with deposition of abnormal collagen material, particularly in the posterior collagen layer, and formation of guttate excrescences and pits.