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.