Persistent corneal haze after excimer laser photokeratectomy in plasminogen-deficient mice.
OBJECTIVE
Excimer laser photorefractive keratectomy creates a nonvascular wound of the cornea. Fibrin deposition and resolution after excimer laser photokeratectomy were investigated in relation to corneal repair and restoration of clarity in mice with a genetic deficiency of plasminogen.


METHODS
A Summit Apex Laser (Summit, Waltham, MA) was used to perform 2-mm, 175-pulse, transepithelial photoablations that resulted in deep stromal keratectomies. Photokeratectomy was performed on the corneas of plasminogen-deficient (Plg-/-) mice and littermate control animals. Eyes were examined for re-epithelialization and clarity throughout the 21-day observational period. Histologic sections were taken during the observational period and fibrin(ogen) was detected immunohistochemically.


RESULTS
Re-epithelialization was rapid and complete within 3 days in both control and Plg-/- animals. Exuberant corneal fibrin(ogen) deposition was noted in Plg-/- mice and sparse fibrin(ogen) deposition in control mice on days 1 and 3 after injury. Fibrin(ogen) deposits resolved in control mice but persisted in Plg-/- mice (74% of eyes at 21 days; P < 0.004). Corneal opacification, scarring, and the presence of anterior chamber fibrin(ogen) occurred in plasminogen-deficient mice but not in control mice.


CONCLUSIONS
Fibrin(ogen) deposition occurs during corneal wound repair after photokeratectomy. Impaired fibrinolysis in Plg-/- mice caused persistent stromal fibrin deposits that correlated with the development of corneal opacity.
Drew
A F
AF
Children's Hospital Research Foundation, Cincinnati, Ohio, USA.
Schiman
H L
HL
Kombrinck
K W
KW
Bugge
T H
TH
Degen
J L
JL
Kaufman
A H
AH
D000818:Animals; D003315:Cornea / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D003318:Corneal Opacity / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D005337:Fibrin / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D007124:Immunoenzyme Techniques; D054018:Lasers, Excimer; D051379:Mice; D008817:Mice, Mutant Strains; D018903:Photorefractive Keratectomy / Q000009:adverse effects*; D010958:Plasminogen / Q000172:deficiency*; D014945:Wound Healing
D005337:Fibrin; D005340:Fibrinogen; D010958:Plasminogen