The Effect of Intralamellar Water-Impermeable Membranes on Corneal Hydration

Abstract

Knowles,¹ using techniques originated by Bock and Maumenee,² reported that the cornea anterior to a water impermeable intralamellar membrane invariably degenerates in the rabbit, but that it remains virtually intact in monkeys. He postulated that the degenerative changes in the rabbit were the result of drying and that the reason for the difference in the response between the rabbit and the monkey could be that the rabbit blinks less frequently. Brown and Dohlman³ observed that in the rabbit the cornea in front of an intralamellar membrane thinned before it degenerated but that both of these phenomena could be prevented by tarsorrhaphy. They attributed this thinning and degeneration to dehydration, which is the result of an augmentation of normal evaluation by the barrier effect of the membrane. These authors placed silicone implants with intralamellar supporting membranes under lamellar grafts in humans with edematous corneas. The corneas anterior to