Susceptibility of the Corneal Epithelial Basement Membrane to Injury in Diabetic Rabbits

Abstract

ABSTRACT

Delayed healing and recurrent erosions of the corneal epithelium are frequently observed in patients with diabetes mellitus, particularly following vitrectomy. We reported previously that the basement membrane is damaged when the corneal epithelium is removed by freezing in diabetic, but not control, rabbits. The purpose of this study was to determine if the corneal epithelial basement membrane of diabetic rabbits would also be more susceptible to damage when other methods were used to remove the epithelium (n-heptanol, scraping, and iodine–cocaine cauterization).

Removal of the corneal epithelium with n-heptanol did not result in damage to the basement membrane in either group. In contrast, scraping resulted in extensive damage in 50% of the diabetic animals, but in none of the controls, and iodine–cocaine cauterization resulted in extensive damage in 75% of the diabetic but in only 25% of the control animals. The results of this study confirm that the epithelial basement membrane of the cornea in diabetic rabbits is more susceptible to injury than that of controls, and suggest that epithelial healing problems in patients with diabetes may be related to basement membrane damage.