Vision stable with PRK out to 14 years, study finds

J Refract Surg. 2009;25(6):545-552.

A majority of patients followed to 14 years after PRK were satisfied with their refractive correction and maintained vision at least equal to preoperative values, according to a study.

In the prospective study, 31 patients were examined from an original cohort of 50 patients who underwent PRK for low myopia of less than –6 D (range –1.5 D to –5.75 D) or high myopia of –6 D or higher (range –5.75 D to –13 D).

After 14 years, manifest refraction spherical equivalent was –0.17 D in the low myopia group and –0.67 D in the high myopia group. Uncorrected visual acuity was –0.06 logMAR in the low myopia group and –0.11 logMAR in the high myopia group. Best corrected visual acuity was 0.00 logMAR in the low myopia group and –0.03 in the high myopia group.

Postoperative results stabilized at 6 months after surgery. At 3 months, 6 months and 14 years, there was no correlation between preoperative and postoperative refraction, and "these data confirm stabilization of the postoperative refraction within 6 months after PRK," the study authors said.

Haze also stabilized at 6 months. Immediately after surgery and out to 6 months, haze increased in both groups, then declined until 1 year, with no change at year 14.

"At the end of follow-up, 30 (97%) eyes of the low myopia group and 17 (94%) of the high myopia group had clear corneas," the authors said.

There were no late complications noted in the study.