Wavefront aberrations and subjective quality of vision after wavefront-guided LASIK

Purpose. To investigate the clinical impact of the postoperative ocular wavefront error (WFE) on subjective quality of vision (SQV) after LASIK. Method. Forty-one myopic eyes of 21 patients underwent uneventful LASIK (median -4.63 D). Preoperatively and 1 month postoperatively, WFE measurements were performed and overall SQV was assessed for two lighting conditions (photopic and mesopic) with a questionnaire. Three different WFE representations were computed for a pupil diameter of 6 mm: (1) the visual quality metric VSOTF (visual Strehl ratio based on the optical transfer function), (2) RMS (root mean square) values of the Zernike orders 2-5, and (3) individual Zernike coefficient for orders 2-5. The impact of the postoperative WFE on SQV was calculated using linear regression analysis. Results. For photopic conditions R-2 was 0.24 for model 1 (VSOTF), 0.31 for model 2 (RMS values), and 0.29 for model 3 (Zernike coefficients). Second-and fifth-order aberrations had significant influence on SQV. For mesopic conditions, results were similar. Conclusion. Subjective quality of vision after wavefront-guided LASIK could be explained partially by the ocular WFE.