Retinal straylight and light distortion phenomena in normal and post-LASIK eyes

To assess the relationship between measures of light distortion and retinal straylight in normal and post-LASIK subjects.

Cross-sectional, non-randomized, masked observational case series

Clinica Oftalmologica Novovision, Madrid, Spain.

Thirty eyes from 30 healthy subjects (mean age 33.9 ± 8.3 years old; mean spherical equivalent (MSE) -2.06 ± 1.40 D) and thirty six eyes from thirty six refractive surgery patients (mean age 36.1 ± 7.7 years old; mean preop MSE -3.43 ± 2.23 D) were examined with the Starlights and the C-Quant straylightmeter in a case-control study.

The age of both treated and control groups was not statistically different (p > 0.05). Statistically significant differences between controls and post-LASIK eyes were found for luminous distortion index (LDI), but not for retinal straylight. Correlation analysis yielded significant correlation between retinal straylight Log(s) values and BCVA measures (r = 0.379, p = 0.002). Control subjects showed significant correlation between MSE and retinal straylight Log(s) values (r = -0.650, p < 0.001), while post-LASIK eyes showed a significant correlation between LDI and Log(s) values (r = 0.338, p = 0.044) and between Log(s) values and BCVA (r = 0.460, p = 0.005). Correlation between measures obtained by both methods was higher after LASIK than in control eyes, although values were quite scattered in any case.

Light distortion phenomena and retinal straylight measures are correlated in both normal and postsurgical eyes. Both parameters are increased in LASIK subjects compared to control non-operated subjects.