Eighteen‐year follow‐up of excimer laser photorefractive keratectomy. Issue 1 (January 2015)

• Record Type: Journal Article
• Authors: Shalchi, Zaid; O'Brart, David P.S.; McDonald, Robert J.; Patel, Parul; Archer, Timothy J.; Marshall, John
• Is Part Of: Journal of cataract and refractive surgery. Volume 41:Issue 1(2015)
• Publication Date: 2015-01
• Subjects: 617.7
• DOI: 10.1016/j.jcrs.2014.05.034
• Languages: English
• ISSNs: 0886-3350

Abstract

Abstract : Purpose : To evaluate the long‐term efficacy of photorefractive keratectomy (PRK). Setting : University Hospital, London, United Kingdom. Design : Prospective case series. Methods : One eye of patients who had PRK 18 years previously was examined. All had myopic corrections with a 6.0 mm optical zone. Results : Forty‐six patients were examined. The mean preoperative spherical equivalent (SE) refractive error was −4.86 diopters (D) (range −2.75 to −7.375 D). The mean programmed correction was −4.43 D (range −2.50 to −7.00 D). Between 1 year and 18 years, the mean change in SE was −0.31 D ( P = .06) and a significant increase in variance occurred ( P < .002). The mean change in SE was −0.54 D in patients younger than 40 years at the time of correction ( P < .02) and −0.05 D in patients older than 40 years ( P = .9). The mean SE change was −0.40 D in women ( P < .04) and −0.08 D in men ( P = .8). The efficacy index was 0.58. The safety index was 0.998. The corrected distance visual acuity (CDVA) improved significantly from 1 to 18 years ( P < .01). Ninety‐six percent of corneas were clear at 18 years, with a reduction in haze scores ( P < .001). There was no evidence of ectasia. Conclusions : A significant increase in myopic SE occurred between 1 year and 18 years after PRK in patients younger than 40 years and in women. Predictability decreased between 1 year and 18 years. The procedure was safe with no long‐term complications. The CDVA and corneal transparency improved with time. Financial Disclosure : Dr. Marshall was a consultant to Summit Technology, Inc. No author has a financial or proprietary interest in any material or method mentioned.