[Studies on the stabilization of the cornea in rabbits].
BACKGROUND
The mechanical stabilization of the cornea in keratoconus may delay progression of this disease. The cross-linking techniques optimized in corneas of enucleated porcine eyes were investigated under in vivo conditions in rabbits to estimate the biocompatibility and duration of the stiffening effect.


METHODS
Twenty-eight rabbits were treated monocularly, the fellow eye serving as control. The epithelium was mechanically removed and 19 eyes were treated with riboflavin plus ultraviolet irradiation (365 nm, 2 mW/cm2) for 45 min and 9 eyes with 0.075% glutaraldehyde for 20 min. After treatment, the eyelids were sutured for 3 days. The healing process was controlled by slit-lamp examination and photographically documented. After 1 month, 20 animals and after 3 months 8 animals were sacrificed, the eyes enucleated, and the stress-strain relation of the corneas measured and compared to the fellow eye.


RESULTS
The epithelium was closed after 4-5 days. The transparency of the corneas remained clear during follow-up, and there were no signs of inflammatory reaction. Stress for a strain of 6% was higher in the treated corneas by a factor of 1.3 +/- 0.66 (P = 0.319) in the glutaraldehyde group and by a factor of 1.6 +/- 0.75 (P = 0.0408) in the riboflavin group at 1 month, and by 1.3 +/- 0.48 (P = 0.07) at 3 months after treatment.


CONCLUSIONS
The cross-linking technique using riboflavin plus UV irradiation is suitable for at least temporarily stiffening the cornea in vivo and seems to be a promising method for conservative treatment of keratectasia.
Spörl
E
E
Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum TU Dresden.
Schreiber
J
J
Hellmund
K
K
Seiler
T
T
Knuschke
P
P
D000818:Animals; D001696:Biomechanical Phenomena; D003315:Cornea / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D016039:Corneal Transplantation; D004202:Disinfectants / Q000494:pharmacology; D005976:Glutaral / Q000494:pharmacology; D007640:Keratoconus / Q000503:physiopathology* / Q000628:therapy; D008422:Materials Testing; D011817:Rabbits; D012256:Riboflavin / Q000494:pharmacology; D013552:Swine; D013997:Time Factors; D014466:Ultraviolet Rays
D004202:Disinfectants; D005976:Glutaral; D012256:Riboflavin