EXCIMER-LASER PHOTOREFRACTIVE KERATECTOMY FOR LOW HYPEROPIA - SAFETY AND EFFICACY

Purpose: To assess the safety and efficacy of photorefractive keratect omy (PRK) to correct low hyperopia. Setting: University of Ottawa Eye Institute, Ottawa General Hospital, Ontario, Canada. Methods: Twenty-f ive eyes with refractions of +1.00 to +4.00 diopters (D) and cylinder of 1.00 D or less were treated for hyperopia with the VISX Star excime r laser system using a refined ablation architecture. Thorough visual assessments were performed preoperatively (baseline) and 1, 3, and 6 m onths postoperatively. Complications were recorded and the level of pa tient satisfaction was noted. Results: Mean spherical equivalent at 6 months was +0.27 D +/- 0.55 (SD), which was an 89% reduction over base line. Eighty-four percent of patients gained two to seven lines of nea r uncorrected visual acuity (UCVA) and 1 patient (4%) lost more than o ne line. Eight percent achieved 20/25 or better UCVA. Approximately ha lf realized their preoperative distance best corrected visual acuity ( BCVA) by 1 month. By the end of the study, all patients had improved, achieved, or were within one line of their baseline distance BCVA. The re were some slight reductions in lower contrast acuity at 6 months, a lthough dim lighting conditions did not further reduce these acuities. Most patients had no clinically meaningful change in cylinder. The mo st common complications included early, transient corneal surface irre gularities and visual symptoms and trace haze (grade less than or equa l to 0.5) in 14 of 23 patients at 6 months. All but 1 patient expresse d a high degree of satisfaction. Conclusions These results support the hypothesis that PRK shows great promise as a safe and effective treat ment for low hyperopia. There were no significant complications and no decentered ablations. The slight regression occurred with or without the presence of trace haze. Overall, refractive stability was encourag ing, although longer follow-up is needed.