Abstract
Purpose: :
There is great debate in the literature and among excimer laser manufacturers as to which laser platform is better: the wavefront guided platform or the wavefront optimized platform. This study aims to determine which laser platform for photorefractive keratectomy (PRK) offers the best visual outcomes.
Methods: :
A retrospective review of data collected from October 2008 to the present at the Warfighter Refractive Surgery Center was preformed. 481 eyes that had undergone wavefront optimized PRK were age matched with 481 eyes that had undergone wavefront guided PRK. The eyes were then stratified according to refractive error into 2 groups: -1 to -3 diopters (D) and -3 to -6 D. The eyes were then further subdivided by age into 3 groups: 20-30 years old, 30-40 years old, and 40+ years old. The 6 month best spectacle corrected visual acuity (BSCVA) and 5% BSCVA (also known as low contrast acuity) were compared between the two groups with a series of student t-tests.
Results: :
In the 20-30 year old group with -1 to -3 D of preoperative refractive error, there was no significant difference in the BSCVA (p=0.389) or 5% BSCVA (p=0.683) at 6 months. In the 20-30 year old group with -3 to -6 D of preoperative refractive error, there was no significant difference in the BSCVA (p=0.46) or 5% BSCVA (p=0.11). In the 30-40 year old group with -1 to -3 D of preoperative refractive error, there was no significant difference in the BSCVA (p=1) or 5% BSCVA (p=0.59) at 6 months. In the 30-40 year old group with -3 to -6 D of preoperative refractive error, there was no significant difference in the BSCVA (p=0.5) or 5% BSCVA (p=0.25) at 6 months. In the 40+ year old group with -1 to -3 D of preoperative refractive error, there was no significant difference in the BSCVA (p=0.18), however, the 5%BSCVA was slightly better in the wavefront optimized group (p=0.017) at 6 months. In the 40+ year old group with -3 to -6 D of preoperative refractive error, there was no significant difference in the BSCVA (p=0.71), although the wavefront optimized outcome for 5% BSCVA was slightly better and approached statistical significance (p=0.06).
Conclusions: :
Our results suggest that, in terms of visual acuity, the wavefront guided and wavefront optimized treatments are equally effective. However, patients over 40 may benefit from better low contrast visual acuity with wavefront optimized treatments.
Keywords: refractive surgery: comparative studies • refractive surgery: comparative studies • laser