Comparison of night driving performance after wavefront-guided and conventional LASIK for moderate myopia.
OBJECTIVE
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.


METHODS
Retrospective, comparative study.


METHODS
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).


METHODS
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
The Navy Refractive Surgery Center, Naval Medical Center, San Diego, California, USA. scschallhorn@yahoo.com
Steve C
SC
Schallhorn
David J
DJ
Tanzer
Sandor E
SE
Kaupp
Mitch
M
Brown
Stephanie E
SE
Malady
D000328:Adult; D001251:Astigmatism / Q000503:physiopathology / Q000601:surgery; D001334:Automobile Driving; D002986:Clinical Trials as Topic; D003198:Computer Simulation; D003319:Corneal Stroma / Q000601:surgery; D019781:Corneal Topography; D005260:Female; D019466:Glare; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology* / Q000601:surgery*; D011184:Postoperative Period; D012189:Retrospective Studies; D013524:Surgical Flaps; D014785:Vision, Ocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology