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Published on: April 3, 2016
Photorefractive keratectomy for residual myopia after radial keratotomy
M E John1, E Martines, T Cvintal
1John-Kenyon Eye Research Foundation, Jeffersonville, Indiana 47130, USA.
Purpose:
To evaluate the results of photorefractive keratectomy (PRK) to treat undercorrected radial keratotomy (RK).
Setting:
Instituto de Oftalmologia Tadeu Cvintal, São Paulo, Brazil.
Methods:
A consecutive series of 28 eyes that had PRK to treat residual myopia after RK were studied. Refractive visual and safety data were collected and evaluated.
Results:
One year after PRK, 75% of eyes had an uncorrected visual acuity of 20/25 or better and 85%, 20/40 or better. All but one case maintained or improved best corrected visual acuity; one case decreased from 20/25 to 20/30. At 1 year, 75% of eyes were within 0.50 diopter (D) of emmetropia and 90% were within 1.00 D. Only one case was more than 1.00 D undercorrected (-1.125 D) at 1 year. Mean pre-RK myopia was -5.90 D (range -2.00 to 11.80 D). Mean spherical equivalent improved from the residual postoperative level of -2.71 D +/- 0.86 (SD) before PRK to -0.21 +/- 0.86 D 1 to 3 months after PRK and to -0.40 +/- 0.43 D 1 year after PRK.
Conclusion:
Photorefractive keratectomy was efficacious in correcting residual myopia after RK in a group of selected patients.
