Wavefront analysis in normal refractive surgery candidates

Abstract

Abstract: : Purpose: To quantify the higher–order aberrations of refractive surgery candidates and compare the wavefront–determined refractions with manifest refractions refined with a ±0.25 Jackson Cross–Cylinder. Methods: Results of 226 consecutive patients (418 eyes) were analyzed with the WaveScan WavePrint system (VISX, Santa Clara, CA). Only patients with normal eyes without previous surgery were included. Results: The mean spherical equivalent (SE) determined with wavefront analysis was –3.40± 3.14 (standard deviation) diopters (D) (range, –10.72 to +5.41 D). The most significant higher–order aberrations were detected with a pupil size of 6 mm (coma 0.14 ± 0.08 µm; trefoil 0.10 ± 0.07 µm; spherical aberrations 0.09 ± 0.07 µm). The mean higher–order aberrations (rms) and total aberrations (rms) were 0.23 ± 0.11 µm and 4.00 ± 2.45 µm, respectively. There was no statistically significant correlation between higher–order aberrations and gender (p=0.78), age (p>0.63) or refractive level (p>0.59). The mean differences in SE, sphere and cylinder between WaveScan measurements and manifest refraction were 0.36 D ± 0.41 D, 0.40 ± 0.44 D and 0.28 ± 0.32 D, respectively. The correlation between wavefront analysis and manifest refraction was significantly lower for high refractive errors. Conclusions: Wavefront analysis proved to be a valuable tool for measuring pre–operative higher–order aberrations and refractive error. This study provides reference values for higher order aberrations in normal refractive surgery candidates.

Keywords: refractive surgery: other technologies • refractive surgery • refraction