Electron microscopy of the epithelial flap created by ethanol treatment in the rabbit corneal epithelium.
OBJECTIVE
To assess the effect of corneal debridement with 25% ethanol on rabbit corneal epithelium by electron microscopy.


METHODS
Department of Ophthalmology, Osaka University School of Medicine, Osaka, Japan.


METHODS
Rabbit corneas were deepithelialized by applying 25% ethanol for 3 minutes, and a hinged epithelial flap was created and repositioned. Ten corneas were evaluated immediately after the epithelial debridement procedure and at 1, 3, and 7 days. Histological changes were evaluated using scanning and transmission electron microscopy.


RESULTS
Corneas treated with ethanol showed a decrease in microvilli, breaks in intercellular junctions, epithelial cell edema, and damage in basement membrane hemidesmosomes. These toxic changes recovered to an almost normal appearance after 24 hours and rapidly improved over the following week. An increase in desquamated cells was observed after debridement; this returned to normal after 1 week according to the normal cellular cycle. Wing cells showed no damage at any stage.


CONCLUSIONS
Although ethanol appeared to have a toxic effect on rabbit epithelial cells, the effect did not persist over time. The first signs of recovery were observed 24 hours after debridement, and full recovery was observed over the following week. The ethanol path to the central basement membrane appeared to be centripetally from a round cut through the basement membrane, leaving the wing cells intact.
Serrano
Daniel
D
Department of Ophthalmology, Osaka University Medical School, Suita, Japan.
Hibino
Sawako
S
Nishida
Kohji
K
Maeda
Naoyuki
N
Tano
Yasuo
Y
D000818:Animals; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000648:ultrastructure*; D000431:Ethanol / Q000494:pharmacology*; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008871:Microvilli / Q000648:ultrastructure; D011817:Rabbits; D013997:Time Factors
D000431:Ethanol