Elektronenmikroskopische Untersuchungen über den Aufbau des Pigmentepithels an der Ora serrata

Abstract

The structure of the pigment epithelium at the ora serrata is examined in 10 human eyes aged from 31 to 90 years. The cells of the pigment epithelium show a different construction depending on their position relative to the ora. Directly at the ora serrata, in the cohesion band, the cells are higher and contain more pigment granula than those which are situated in a central region. In this sector we sometimes find overlapping of cells, which feigns two layers of epithelium. There are clearly fewer basal folding ins of the pigment epithelial cells at the ora than in the other parts of the retina. At the ora serrata pathological changes start in the 3rd decade of life. They include swelling and later on more or less pronounced cystoid degeneration of the epithelial cells. Within Bruch’s membrane two kinds of cells are seen. In the ora gap six types of free cells can be distinguished, whose origin is discussed especially. Probably they originate from the chorioidea, the pigment epithelium and the sensory retina.