• Five rhesus monkey eyes underwent repeated argon fluoride (193 nm) excimer laser myopic photorefractive keratectomy 3 months following an initial ablation that had produced mild subepithelial haze. At 3 months all eyes had development of a dense subepithelial opacity and a thickened epithelium (12 cells, 80 μm) with vacuolization of basal cells, fragmented basement membrane, and a layer of subepithelial fibrosis containing activated fibroblasts. By 6 months the opacity was clearing; epithelium was thinner (50 μm); subepithelial fibrosis was more lamellar. By 15 months only mild haze persisted clinically; epithelium was 30 μm thick, with persistent basal vacuolization and focal basement membrane disruption; subepithelial fibrous tissue was more organized. Early repeated excimer laser ablation of the monkey cornea apparently induces vigorous stromal wound healing. Use of shallower ablations, corticosteroids, or a longer delay between ablations may be necessary for repeated laser surgery to be practical clinically.
Hanna KD, Pouliquen YM, Waring GO, Savoldelli M, Fantes F, Thompson KP. Corneal Wound Healing in Monkeys After Repeated Excimer Laser Photorefractive Keratectomy. Arch Ophthalmol. 1992;110(9):1286-1291. doi:10.1001/archopht.1992.01080210104035