CORNEAL HYALURONAN CONTENT DURING POST-ABLATION HEALING - EVIDENCE FOR A TRANSIENT DEPTH-DEPENDENT CONTRALATERAL EFFECT

The hyaluronan content during wound healing following excimer laser ph otoablation was investigated. Rabbit corneas were photoablated (Summit Omnimed, 193 nm, 5 mm diameter, 50 mu m and 100 mu m depth). Central optical zones of photoablated and contralateral corneas were removed 7 , 30 and 90 days after surgery. Corneas from 2 untreated rabbits were used as control. Hyaluronan content was determined after pepsin-solubi lization using an alkaline-phosphatase linked hyaluronectin sorbent as say. The hyaluronan content of non-photoablated contralateral corneas was significantly increased and the changes appeared depth dependent. Hyaluronan content returned to control levels by the first month at 50 mu m depth and by the third month at 100 mu m depth in contralateral corneas. The hyaluronan content of the photoablated corneas was not si gnificantly different from that of the non-photoablated contralateral sample regardless of the depth of photoablation. By contrast, the hyal uronan content of the treated corneas was significantly higher than th at of the controls during the first month post-surgery and returned to control values by the third month. Thus the hyaluronan contents in th e photoablated and contralateral corneas after excimer laser corneal p hotoablation were very similar during wound healing. This study shows that excimer laser photoablation induced transient depth-dependent con tralateral alterations of the hyaluronan content. (C) 1997 Academic Pr ess Limited.