Prospective bilateral study of night glare after laser in situ keratomileusis with single zone and transition zone ablation

Abstract

Purpose: Evaluation of night glare after excimer laser in situ keratomileusis (LASIK) using two different ablation zone diameters.

Methods: One hundred and twenty eyes of 60 consecutive myopic patients received LASIK with the Nidek EC-5000 excimer laser. Eyes were randomized so that every patient had a single ablation zone of 5.5 mm on one eye and an ablation zone of 5.5 mm with a transition zone of 1.0 mm diameter larger on the other eye. Night glare was measured by two methods; a spot light test and a subjective questionnaire.

Results: At 6 months, 54 patients (90%) were examined; results of the spot light test showed that 40 patients (74.1%) perceived more glare with the eye with the single ablation zone; the subjective questionnaire indicated that 22 patients (40.7%) had more night glare with the eye with a single ablation zone compared to the other eye. The use of the transition zone increased the required total ablation depth by 20%.

Conclusion: The use of a peripheral transition 1.0 mm diameter larger than the ablation zone significantly decreased night glare after LASIK with slight increase in the required central ablation depth.