Incidence of rainbow glare after laser in situ keratomileusis flap creation with a 60 kHz femtosecond laser.

PURPOSE: To report the incidence of and factors associated with rainbow glare after laser in situ keratomileusis (LASIK) flap creation with a 60 kHz femtosecond laser.

SETTING

Department of Refractive Surgery, Cleveland Clinic Cole Eye Institute, Cleveland, Ohio, USA.

METHODS

Consecutive patients having LASIK by the same surgeon were questioned during postoperative examinations or by telephone about postoperative rainbow glare (radiating colors around a white light at night). Femtosecond laser (IntraLase) settings included pulse frequency 60 kHz, flap thickness 90 to 110 mum, and spot/line separation 8 mum. Raster energy was 0.8 microJ (75% of eyes) and 1.0 to 1.1 microJ (25%). Excimer laser ablation was performed with the LADAR 4000 or 6000 platform using custom or conventional treatments.

RESULTS

Of 260 consecutive patients, 256 (98.5%) were successfully contacted. Fifteen patients (28 eyes) reported postoperative rainbow glare (5.8%), described as 4 to 12 bands of color around a white light, with 6 bands most common. The symptom did not correlate with refractive error, age, or sex but was more frequent at 1.0 microJ or 1.1 microJ raster energy (11.6%) than at 0.8 microJ (4.1%). The incidence followed a bimodal distribution, with the first grouping due to inadequate alignment and higher energy just after laser installation and the second just before a later maintenance service call.

CONCLUSION

Rainbow glare is a mild optical side effect of femtosecond LASIK. In this study, higher raster energy levels and length of time between service calls were associated with the occurrence of rainbow glare.