Effect of Astigmatism Treatment With Three Excimer Lasers After Photorefractive Keratectomy.

OBJECTIVES

To compare astigmatism correction after photorefractive keratectomy (PRK) using three excimer laser devices, Alcon Wavelight EX500, Schwind Amaris 1,050, and Technolas Teneo317 M2.

METHODS

This retrospective study included 414 eyes from 414 subjects with a history of PRK performed using Alcon Wavelight (n=172), Schwind Amaris (n=122), and Technolas (n=120). Uncorrected & corrected distance visual acuity (UDVA & CDVA), and refractive status (spherical equivalent (SE) and vector analysis (J0 and J45)) were postoperatively recorded at the 6-month and 12-month examinations.

RESULTS

The mean CDVA and J45 at 6-month and 12-month showed no statistically significant difference among the three different excimer lasers ( P >0.05). There was a statistically significant difference in mean UDVA and J0 at 6-month and 12-month after PRK among the three groups, with no statistically significant difference between Alcon Wavelight and Schwind Amaris lasers, while both of the prior lasers showed a significant difference with the Technolas laser. The highest and lowest changes in the magnitude of J0 in 6-month and 12-month follow-ups were seen for the Alcon Wavelight and Technolas groups, respectively. Both Schwind Amaris and Technolas had a small hyperopic SE while the Alcon Wavelight's SE was minimally myopic. This difference in SE between Alcon Wavelight and both Schwind Amaris and Technolas reached statistical significance.

CONCLUSION

While all three lasers performed well in reducing preoperative astigmatism; however, the Alcon Wavelight and Schwind Amaris were more effective in correcting astigmatism than the Technolas. The difference between the Alcon Wavelight and Schwind Amaris did not reach statistical significance.