Comparison between central corneal thickness, anterior chamber depth and axial length values with and without contact lenses

Purpose: To compare the values of central corneal thickness (CCT), the anterior chamber depth (ACD) and the axial length (AL) on measurements performed with and without contact lenses (CL) in healthy subjects. ACD was measured with two different devices (Visionix 120+ and EchoScan US-800) and the values were also compared between them. Material and methods: 20 volunteer participants (6 men and 14 women, 24.8 ± 2.73 years) were recruited. In a single visit, participants underwent autorefraction, biometry, topography and pachymetry with the naked eye (without CL). Then, biometry and pachymetry were repeated twice wearing two different CL (Somofilcon A and Nesofilcon A) of -3.00D lens power fitted in random order. Data were compared using t-tests for related samples. Results: CCT values wearing CL were significantly higher than those obtained with the naked eye (Paired t-test; both p ≤ 0.001). On the other hand, no significant differences were found between the ACD or AL values with the naked eye versus any of the CL studied (Paired t-test, all p ≥ 0.111). The ACD values comparing Visionix120+ to EchoScan US-800 measurements were significantly different with both the naked eye and with any CL (Paired t-test; all p ≤ 0.001). Conclusion: CCT measurements cannot be performed while wearing CL. In contrast, ACD and AL measurements were not affected by the use of any CL. In addition, it was observed that ACD results from both devices are not interchangeable neither when measured with the naked eye nor using any CL.