Human excimer laser keratectomy. Immunohistochemical analysis of healing.

OBJECTIVE

To analyze human corneal responses to excimer laser by immunohistochemistry.

METHODS

Corneas cultured for 3 weeks after laser ablation or taken from patients 5 to 16 months after laser treatment were exposed to antibodies to beta, integrin; types VII, IV, and III collagen; fibronectin; type I procollagen; and prolyl 4-hydroxylase. Antibody distributions were compared with those of normal corneas and unablated regions of treated corneas.

RESULTS

After 3 weeks, distribution of beta, integrin, and types VII and IV collagen was patchy; heavy deposits of fibronectin appeared subepithelially. Keratocytes stained for prolyl-4-hydroxylase and type I procollagen. With increasing postoperative time, fibronectin diminished, and beta 4 integrin and type VII collagen became linear, stromal staining of types III and IV collagen increased and their diminished.

CONCLUSIONS

Components of basement membrane, attachment complexes, and stromal matrix are synthesized shortly after laser treatment. Changes in these elements persist for 16 months in the human cornea.