To compare preoperative and postoperative changes in simulated night driving performance after wavefront-guided (wLASIK) and conventional LASIK (cLASIK) for the treatment of moderate myopia.
Retrospective, comparative study.
All eyes of subjects with a preoperative manifest spherical equivalent (MSE) between −4.50 and −6.00 who underwent night driving simulator (NDS) testing from 2 clinical trials were entered into the study. This comprised 38 cLASIK patients (62 eyes; mean −5.46 diopters [D] MSE) and 21 wLASIK patients (36 eyes, mean −5.20 D MSE).
Patients' records were reviewed from 2 LASIK clinical trials that had similar enrollment criteria. One trial treated patients with conventional LASIK using a bladed microkeratome (cLASIK) and the other treated with a wavefront-guided profile using a femtosecond laser (wLASIK). In both trials, patients with moderate myopia were asked to participate in NDS testing.
Main Outcome Measures
The detection and identification distances of road hazards were measured with and without a glare source before and 6 months after LASIK. Each eye was tested independently in best-corrected trial frames by a masked operator.
In every category, there was a mean reduction in the preoperative to postoperative NDS performance after cLASIK (mean change, −21.3 to −27.9 ft, −6.5 to −8.5 m; 95% confidence interval [CI], −12.0 to −41.3 ft, −3.7 to −12.6 m); there was a corresponding mean improvement after wLASIK (mean change +15.0 to +29.1 ft, +4.6 to +8.9 m; 95% CI, +8.3 to +41.5 ft, +2.5 to +12.6 m). Significant differences between cLASIK and wLASIK NDS performance was observed in every category (P<0.;01, Tukey's honest significant difference for unequal numbers). A clinical relevant loss of NDS performance (>0.5 seconds) was observed in 32% to 38% of cLASIK eyes for all tasks, whereas only 0% to 3% of eyes had this loss after wLASIK. Between 2% and 7% of cLASIK eyes and 11% and 31% of eyes had a significant postoperative improvement in NDS performance in every task.
Wavefront-guided LASIK to correct myopia combined with a femtosecond laser flap significantly improved mean night driving visual performance and was significantly better than cLASIK using a mechanical keratome.
Ophthalmology Volume 116, Issue 4, April 2009, Pages 702-709