EFFECT OF VARIATIONS IN SURGICAL TECHNIQUE AND PATIENT-MANAGEMENT ON OUTCOMES OF PHOTOREFRACTIVE KERATECTOMY

PURPOSE: To describe variation in surgical and patient management and to assess their effect on 12-month outcomes of photorefractive keratec tomy (PRK). METHODS: The following variations in surgical/patient mana gement related to PRK were observed and assessed: treatment based on c ycloplegic refraction, administration of anesthesia, marking of visual axis, diameter of zone marker, method of epithelial removal, use of i ntraoperative artificial tears, type of fixation during surgery, repla cement of epithelium after surgery, use of a bandage contact lens or t wo pressure patches, and use of topical nonsteroidal antiinflammatory drugs after surgery. The outcomes assessed were spherical equivalent m anifest refraction, spectacle-corrected visual acuity and uncorrected visual acuity. RESULTS: One year clinical outcomes were assessed prosp ectively for a group of 645 eyes that underwent PRK or photoastigmatic keratectomy. Spherical equivalent refraction and uncorrected visual a cuity were better with decreasing amounts of preoperative myopia (both F>30.0, both p=0.0001). Although some surgical variations produced st atistically significantly better uncorrected visual acuity on univaria te analyses, none of the variations in the techniques assessed were fo und to be statistically significantly related to clinical outcomes aft er controlling for preoperative spherical equivalent refraction (all F <2.5, all p>0.10). None of. the surgical variations were associated wi th loss of spectacle-corrected visual acuity (all p>0.10). CONCLUSION: Clinical outcomes of PRK were not significantly affected by minor var iations in clinical and surgical practice.