Effect of contact lenses on ocular biometric measurements based on swept-source optical coherence tomography

ABSTRACT Purpose: To determine the reliability of swept- source optical coherence tomography in cases in which soft contact lenses cannot be removed when acquiring biometric measurements. Methods: Eight subjects were included and only one eye per participant was analyzed. Each eye was measured six times by swept-source optical coherence tomography with the IOLMaster 700 instrument (Carl Zeiss Meditec, Jena, Germany). Axial length, central corneal thickness, anterior chamber depth, lens thickness, and keratometric measurements were evaluated for the naked eye and while wearing soft contact lenses of three different powers (-1.5, -3.0, and +2.0 D). Results: There were statistically significant changes in axial length, central corneal thickness, anterior chamber depth, and keratometric measurements with soft contact lenses as compared to the naked eye (p<0.001). However, there were no significant differences in lens thickness outcomes between the naked eye and while wearing the three soft contact lenses (p>0.5). The changes in axial length, central corneal thickness, and anterior chamber depth were lens-specific and dependent on the thickness of the lens used. Conclusions: Sept-source optical coherence tomography based lens thickness measurements while wearing soft contact lenses are comparable to those of the naked eye. However, the thickness and the optical design of the soft contact lens may lead to significant differences in the axial lengh, central corneal thickness, anterior chamber deph, and keratometric measurements.