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