Haze development after photorefractive keratectomy: mechanical vs ethanol epithelial removal in rabbits.

摘要

PURPOSE: To compare mechanical and ethanol epithelial removal with respect to myofibroblast development and haze formation after photorefractive keratectomy (PRK). METHODS: Seventeen rabbits underwent mechanical or ethanol debridement, and the opposite eye of each rabbit served as an unwounded control. In both groups, the epithelium was removed with a spatula and discarded. A -9.00-diopter PRK was performed in each eye. The level of haze in each cornea at 4 weeks was graded at the slit-lamp microscope according to the Fantes scale. Myofibroblast generation was detected with immunocytochemistry for alpha-smooth muscle actin (alpha-SMA) and cells were quantitatively analyzed. RESULTS: No difference was noted between the two groups in alpha-SMA + myofibroblasts 4 weeks after surgery (43.6+/-2.0/400x field and 45.7+/-4.8/400x field in ethanol and mechanical groups, respectively) (P=.10). A slight difference was noted but did not reach statistical significance with regard to stromal haze between ethanol andmechanical groups (2.0+/-0.5 and 2.3+/-0.4, respectively, P=.063). The ethanol and mechanical groups were statistically different when compared to controls regarding stromal haze and alpha-SMA+ cells (P<.0001for all comparisons). CONCLUSIONS: No difference was noted in clinical haze or myofibroblast generation between corneas that had PRK with mechanical or ethanol epithelial debridement.