Clinical applicability of the WaveFront Phase Imaging Sensor in the Keratoconus Disease

Abstract

SignificanceThe analysis of the wavefront phase of keratoconus eyes has become increasingly important due to its impact on the assessment of visual quality loss, irrecoverable with conventional optical treatments, and the understanding of morphological changes in corneal structures.AimThe aim of this work is to quantitatively assess the wavefront phase of keratoconic eyes measured by the novel high-resolution ocular aberrometer t·eyede (based on WaveFront Phase Imaging Sensor).ApproachThe measurements with this device were taken on healthy and keratoconic eyes at the Hospital Universitario Fundación Jiménez Díaz (Madrid, Spain). The wavefront phase recovered is post-processed and displayed in different phase maps, using exclusively the high-pass filter map for this study. From this map, the Root Mean Square, the Peak-to-Valley, and the amplitude value of the predominant obtained from its Fourier Transform are the parameters to distinguish between healthy and keratoconic eyes. Furthermore, the banding pattern observed in most keratoconic eyes is quantitatively analyzed by means of its period and orientation calculated from the Fourier Transform.ResultsThe Control group was composed of 43 healthy eyes, and the Pathological group presented 43 keratoconic eyes. Regarding the first three parameters used to compare both groups, there were significant statistical differences between them in all parameters, where the values obtained with the keratoconic group were higher than those of the healthy group. Although the values cannot be statistically comparable between stages, they tended to increase according to the severity of the disease. On the other hand, analyzing the banding pattern, the mean value of the period was approximately 50 µm, and most orientations were obliquus, tending to be horizontal rather than vertical.ConclusionsThe present study demonstrates that the objective analysis of the high frequencies detected by this wavefront sensor is a potential tool to reliably advise in the keratoconus diagnosis. Furthermore, combining this achievement with the quantitative assessment of the banding pattern would be used to objectively monitor the internal corneal status throughout the disease and its treatment optimization and surgery time.