Risk factors for night vision complaints after LASIK for myopia.

Purpose: To study the preoperative risk factors for night vision complaints (NVCs) after LASIK in a clinical setting.

Design: Retrospective noncomparative case series.

Participants: Seven hundred ninety-five patients (1488 eyes) who underwent LASIK for myopia up to -9.75 diopters (D) (from January 1 to December 31, 1999).

Setting: Private clinic.

Methods: A complete preoperative examination was performed. Patients had bilateral LASIK surgery using the Nidek EC-5000 non-wavefront guided slit-scanning excimer laser and the Moria LSK One microkeratome. Patients were observed postoperatively for 12 months.

Main Outcome Measures: The reported NVCs for each eye were rated on a subjective scale based on functional visual comfort. Clinically important NVC odds ratios (ORs) were calculated.

Results: Reports of NVCs decreased considerably from 25.6% at 1 month to 4.7% at 12 months postoperatively, at which time all patients reported similar NVCs in both eyes. Stratification of risk factors at 12 months postoperatively showed a 2.8-times increase in NVCs for initial myopia of >5 D, a 2.5-times increase for an optical zone of
Conclusions: Attempted degree of spherical correction, age, optical zone, and postoperative spherical equivalent were major risk factors of NVCs throughout the first postoperative year, whereas pupil size was not. Future wavefront studies that characterize higher order aberrations might be helpful for understanding individual visual aberrations while predicting quality of vision.