Comparison of PRK and LASIK for Extreme Myopia

Tuesday, April 21, 2015: 2:11 PM
Room 1B (San Diego Convention Center)
Karolien Termote, MD, FEBO
Simon P. Holland, MB, FRCSC
David T.C. Lin, MD, FRCSC

Purpose
To compare one-year outcomes of extremely myopic patients between PRK and LASIK.

Methods
We present a retrospective, consecutive case series and chart review of 219 eyes with more than -10.00D spherical equivalent (SE) preoperatively that underwent laser refractive surgery using Allegretto Wavelight laser. 183 eyes were treated via trans epithelial PRK and 36 were treated via LASIK. One year postoperative uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), manifest refraction predictability and complications were evaluated and compared.

Results
42% (77/183) PRK patients showed UCVA ≥20/20 compared to 33% (12/36) of LASIK patients. 67% (123/183) PRK patients had no change in BSCVA compared to 64% (23/36) LASIK patients, 14% of patients in both groups lost one line (26/183 and 5/36 respectively). 66% (121/183) PRK patients showed postoperative SE +/- 0.50D compared to 72% (26/36) of LASIK patients. Mild complications occured such as temporary loss of vision due to punctate keratopathy (0,04% (3/183) PRK patients compared to 22% (8/36) LASIK patients) and early haze formation (0,03% (5/183) PRK patients compared to 0% (0/36) LASIK patients). Only the higher amount of punctata keratopathy in the LASIK group was statistically significant (P<0,05).

Conclusion
In extreme myopia, more patients achieved 20/20 UCVA with PRK than LASIK. This result was not significant. PRK for extreme myopia appears to be non-inferior to LASIK with potentially higher safety.