Ultra-High Resolution Optical Aberrometry in Patients with Keratoconus: A Cross-Sectional Study

IntroductionThis study performs optical aberration assessment in patients using a novel ultra-high-resolution device. The objective of this study is to analyze optical aberrations, especially the very high order wavefront (more than 10th order of Zernike coefficients), and compare between keratoconus and healthy patients.MethodsIn this cross-sectional study, we analyzed 43 eyes from 25 healthy patients and 43 eyes from 27 patients with keratoconus using corneal tomography and a very high-resolution (8.55 mu m) aberrometer prototype (T-eyede) outfitted with a sensor originally developed for use in the field of astrophysics. Corneal aberration values were assessed using an optical model built with Zemax optical software, while ocular aberrations were assessed using T-eyede. In addition, image-processing analysis was performed of the wavefront phase, creating a high-pass filter map.ResultsWe found lower values for ocular aberrations than corneal aberrations in both groups (p < 0.001). Specifically, we found a reduction in primary astigmatism (0.145 mu m) and primary coma (0.017 mu m). Also, the keratoconus group showed significantly higher wavefront aberration values compared with controls (p < 0.001). An analysis of the high-pass filter map revealed 2 contrasting results: one smooth or clear, while the other presented a banding pattern. Almost all in the control group (95%) showed the first pattern, while 77% of the keratoconus group showed a banding pattern on the filtered map (chi-squared test, p < 0.001).ConclusionThis device provides reliable, precise measurements of ocular aberrations that correlate well with corneal aberrations. Furthermore, the extraordinary high-resolution measurements revealed unprecedented micro changes in the wavefront phase of patients with keratoconus that varied with disease stage. These findings could lead to new screening or follow-up methods.

Automated summary

This study utilizes a novel ultra-high-resolution device to assess optical aberrations in patients. The objective is to analyze optical aberrations, particularly very high order wavefront, and compare between keratoconus and healthy patients.