Photorefractive keratectomy using the meditec MEL 70 G-scan laser for hyperopia and hyperopic astigmatism.

Abstract

To evaluate the results of photorefractive keratectomy (PRK) using Gaussian flying spot technology in the treatment of hyperopia and hyperopic astigmatism. Two hundred eyes were evaluated with 12-month follow-up. An Asclepion-Meditec MEL 70 G-scan flying spot ArF excimer laser with a Gaussian scanner was used (6.0-mm treatment zone and 9.0-mm transition zone). Eyes were divided into four groups: Group 1 (spherical hyperopia up to +3.50 D and astigmatism less than 1.00 D, n=62); Group 2 (hyperopia up to +3.50 D and astigmatism of 1.00 D or more, n=44); Group 3 (hyperopia greater than +3.50 D and astigmatism less than 1.00 D, n=56); and Group 4 (hyperopia greater than +3.50 D and astigmatism of 1.00 D or more, n=38). In Group 1, 82.2% (51/62 eyes) were within +/-0.50 D of target refraction; 88.7% (55/62 eyes) had 20/20 or better uncorrected visual acuity; 1.6% (1/62 eye) lost two or more lines, 3.2% (2/62 eyes) gained two or more lines of spectacle-corrected visual acuity. In Group 2, 68.1% (30/44 eyes) were within +/-0.50 D; 77.2% (34/44 eyes) had 20/20 or better uncorrected visual acuity; 9.1% (4/44 eyes) lost two or more lines of spectacle-corrected visual acuity. In Group 3, 76.8% (43/56 eyes) were within +/-0.50 D; 78.6% (44/56 eyes) had 20/20 or better uncorrected visual acuity; 5.4% (3/56 eyes) lost two or more lines of spectacle-corrected visual acuity. In Group 4, 42% (16/38 eyes) were within +/-0.50 D; 60.5% (23/38 eyes) had 20/20 or better uncorrected visual acuity; 15.8% (6/38 eyes) lost two or more Snellen lines. PRK with the flying spot Meditec MEL 70 G-scan was most safe and effective for low hyperopia.