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Published on: April 3, 2016
Three year results of refractive keratotomy using the Casebeer System
Purpose:
To analyze the results of one surgeon's first refractive keratotomy surgeries.
Setting:
The Werblin Center, Princeton, West Virginia.
Methods:
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.
Results:
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.
Conclusion:
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.

