[Reepithelialization of keratolens in the wound healing process following epikeratophakia in rabbits].
Most of the complications of epikeratophakia are minor and can be treated successfully. However, approximately 5 to 10% of cases of epikeratophakia result in removal of keratolenses mainly because of the failure to reepithelialize or chronic epithelial defects. In this study, in order to solve this problem we investigated the process of reepithelialization of epikeratophakia in rabbits. Epikeratophakia was performed on rabbit corneas using cryolathed keratolens. Ten, 16, 45, 63 and 90 days after the operation, corneas were excised, labeled with 3H-thymidine and examined histologically using light and electron microscope and autoradiography. 10 to 16 days after the operation, keratolenses were reepithelialized with a very thin epithelium of one or two layers. Epithelium thickened gradually, but was still thinner than normal controls at day 90. At days 10 and 16, basal cells of the epithelium showed high activity of 3H-thymidine incorporation, suggesting active proliferation. After that the proliferating activity decreased gradually and was no longer seen at day 90. Electron microscopic examination revealed no desmosomes or interdigitation between epithelial cells and poorly developed hemidesmosomes between basal cells and basement membrane at day 10, immediately after reepithelialization. At day 90, the epithelium over the keratolens showed areas where the basement membrane was irregular and extensively interrupted. These results indicated that in epikeratophakia, reepithelialization, recovery of epithelial thickness, formation of differentiated desmosomes or hemidesmosomes and normalization of ultrastructural abnormalities took longer than reepithelialization of usual epithelial defects. These results may explain the reason for of clinical problems of chronic epithelial defects or failure of reepithelialization in epikeratophakia. It was suggested that one of the factors causing delayed reepithelialization in epikeratophakia might be the cryolathing process of the keratolenses.
Sahori
A
A
Kazusa
R
R
Katakami
C
C
Tetsumoto
K
K
Yamamoto
M
M
D000818:Animals; D002455:Cell Division; D003315:Cornea / Q000473:pathology* / Q000648:ultrastructure; D016039:Corneal Transplantation / Q000379:methods / Q000473:pathology*; D003896:Desmosomes / Q000648:ultrastructure; D004848:Epithelium / Q000473:pathology / Q000648:ultrastructure; D011817:Rabbits; D014945:Wound Healing