Higher Order Aberrations Induced by Different Soft Contact Lens Brands in Young Adults

Background: Few studies in the literature have compared wavefront aberrations between different hydrogel lens brands. Additionally, very few studies have examined differences in aberration characteristics in the natural eye in comparison to eyes wearing hydrogel lenses. The purpose of this study was twofold – i) Comparison of wavefront aberrations with lens on and off eye ii) To examine for differences in wavefront aberrations between various soft contact lens (SCL) brands. Methodology: A sample of students (N=30; 60 eyes) between the age range of 21-29 years were included. Subjects included were habitual SCL wearers. Information pertaining to the SCL brand and prescription were documented for each subject. For each subject we measured, i) total aberrations, ii) total higher order aberration (HOA), iii) total coma, iv) total trefoil, v) total spherical aberration. Measurements were made with the NIDEK OPD Scan III. Results: A single factor Analysis of Variance (ANOVA) was run on the Root Mean Squared (RMS) data to compare induced aberrations across the different brands of lenses. Overall, the results were statistically non-significant (p > 0.05). A paired, two-tailed t-test was done to compare RMS values for the lens ON and OFF eye conditions. There was a significant increase in the total HOA (p < 0.001); total spherical aberration, (p < 0.042), total trefoil, (p < 0.003) with the lens on eye. There was a significant decrease (p < 0.0001) in total aberrations (lower & higher) with the lens on eye. Conclusion: Our results indicate that soft contact lenses induce a significant increase in higher order aberrations on the eye. The amount of aberration induced does not seem to be significantly different when compared between different hydrogel brands. These results are partially consistent with the findings in the literature and require further research.