HUMAN EXCIMER-LASER KERATECTOMY - IMMUNOHISTOCHEMICAL ANALYSIS OF HEALING

Objective: To analyze human corneal responses to excimer laser by immu nohistochemistry. Methods: Corneas cultured for 3 weeks after laser ab lation or taken from patients 5 to 16 months after laser treatment wer e exposed to antibodies to beta(4) integrin; types VII, IV, and III co llagen, fibronectin; type I procollagen; and prolyl 4-hydroxylase. Ant ibody distributions were compared with those of normal corneas and una blated regions of treated corneas. Results: After 3 weeks, distributio n of beta(4) 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 posto perative time, fibronectin diminished, and beta(4) integrin and type V II collagen became linear; stromal staining of types III and IV collag en increased and then diminished. Conclusions: Components of basement membrane, attachment complexes, and stromal matrix are synthesized sho rtly after laser treatment. Changes in these elements persist for 16 m onths in the human cornea.