Abstract
Purpose :
To describe the visual outcomes of hyperopic photorefractive keratectomy (PRK) versus laser in situ keratomileusis (LASIK) in a large patient population.
Methods :
The records of a large refractive surgery practice (Optical Express, Glasgow, UK), were retrospectively searched to identify all patients who had undergone hyperopic PRK or LASIK between 1/1/2008 and 4/1/2015. Patients were included in this study if they had a manifest spherical equivalent (MSE) of greater than or equal to 0.0 Diopters preoperative, had a refractive target of plano and had at least 3 months of follow up with refraction data after surgery. Descriptive statistics were generated, and a generalized linear method statistical model was used to analyze the differences between the two procedures.
Results :
A total of 54,464 eyes (25,587 patients) underwent LASIK and 4,098 eyes (2,036 patients) underwent PRK and met the inclusion criteria. The average preoperative MSE was higher in the LASIK group than the PRK group (1.94±0.86 vs +1.72±0.82D, p <0.001). The duration of follow up averaged 430±459 days for LASIK patients and 410±414 days for PRK patients (p = 0.019). The average postop sphere at last follow up was +0.26±0.70D for LASIK eyes and +0.18±0.77 for PRK eyes (p<0.001), the average postop cyl at last follow up was -0.43±0.38 for LASIK eyes and -0.42±0.38 for PRK eyes (p=0.005). At their last visit, 69.1% of LASIK eyes and 67.7% of PRK eyes were ±0.5D of plano and 88.8% of LASIK eyes and 86.5% of PRK eyes were ±1D of plano (p<0.001). When controlling for age, ablation pattern, preoperative MSE and gender, patients undergoing PRK were less likely to be within 0.5D of plano (odds ratio 0.84, 95% CI 0.78 to 0.90, p<0.001).
Conclusions :
In this large population of patients with 3 months or greater of follow up, hyperopic PRK and LASIK yielded good visual outcomes. Eyes that underwent PRK were slightly less likely to achieve ±0.5D of their intended refraction than those that underwent LASIK.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.