Straylight measurements in laser in situ keratomileusis and laser-assisted subepithelial keratectomy for myopia

Purpose: To compare straylight values before and 3 months after laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK) and to analyze the causes of any change. Setting: Private refractive surgery clinic, Driebergen, The Netherlands. Methods: Straylight was measured before and after LASIK or LASEK with a C-Quant straylight meter; values were recorded as the straylight parameter log(s). Main outcome measures were the difference between postoperative and preoperative straylight values and factors causing a difference between the values. Results: The study evaluated 102 eyes having LASIK and 137 eyes having LASEK. On average, there was significant improvement in straylight values postoperatively in both groups. The mean decrease was -0.016 log(s) in the LASIK group and -0.026 log(s) in the LASEK group. Nonparametric testing (sign test) showed that the improvement in straylight was statistically significant in more than 50% of eyes in both groups. Straylight improved in 62 eyes in the LASIK group (P<.001) and 78 eyes in the LASEK group (P<.02) and deteriorated in 35 eyes and 58 eyes, respectively. There was an increase in straylight in 17 eyes (7.1%). Clinical correlations were found in some eyes that had increased postoperative straylight values. Conclusion: On average, straylight values 3 months after LASIK and LASEK were slightly decreased from baseline values. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.