Three year results of refractive keratotomy using the Casebeer System

Abstract
To analyze the results of one surgeon's first refractive keratotomy surgeries. The Werblin Center, Princeton, West Virginia. The three year results of 241 consecutive surgical procedures (128 patients) using Casebeer nomograms were examined. The average preoperative myopia was -4.07 +/- 1.89 diopters.(D). Two hundred twenty-two eyes were corrected with a goal of emmetropia. Two hundred of 241 eyes (83%) were followed for 3 years; 35 eyes (15%) were followed for fewer than 3 years after the last enhancement procedure, and 6 eyes (2%) were lost to follow-up. At 3 years postoperatively (range 30 to 44 months), excluding postoperative suture and ALK procedures, mean residual manifest refractive error (spherical equivalent) was -0.04 +/- 0.67 D (-2.25 to + 3.13 D). Mean residual cycloplegic error was + 0.45 +/- 0.76 D (-1.00 to + 4.13 D). Eighty-seven eyes (36%) required between one and six enhancement procedures. One hundred fifteen eyes (52%) had 20/20 or better visual acuity and 214 eyes (96%), 20/40 or better. One hundred fifty-two eyes (84%) were within +/- 1.0 D and 120 eyes (66%) were within +/- 0.5 D. Ten eyes (4%) lost one or more lines of best corrected acuity. Using the Casebeer system for refractive keratotomy, we obtained 20/40 or better uncorrected visual acuity in 96% of eyes with low to moderate levels of myopia. However, a significant number of enhancement procedures, 36% overall, were required to achieve this level of success. Hyperopic shift remains a significant concern following radial keratotomy procedures.