New testing software for quantifying discrimination capacity in subjects with ocular pathologies

Abstract

In the last decade, the use and development of objective optical devices, such as aberrometers and double-pass devices, have expanded to evaluate the optical quality of the human eye. ^{1, 2, 3, 4, 5} With these devices, the aim is to achieve an objective evaluation of the observer's visual state, spending the least time possible in taking the data. This time savings is a great advantage in clinics, where time spent per patient is limited; also, for older patients, speed of examination avoids unnecessary fatigue in the observer. However, these optical devices were previously large and also costly, sometimes prohibitively so. Without these devices, the visual examination of the subject would be limited to the usual psychophysical tests as well as the study of the refractive state of the subject. Therefore, other subjective tests are needed that require the cooperation of the patient to characterize the visual performance of the subject. The discrimination capacity of the subject is an important visual function for this purpose, allowing us to evaluate the real state of vision of the subject and providing an easy tool for detecting potential visual dysfunctions. For these reasons, a new visual test for quantifying discrimination capacity was developed that needs no specific hardware, is free of charge, and is becoming an accessible and easy tool for clinical applications compared to former complex optical devices. On the other hand, the development of simple visual tests that evaluate visual function is an important task for the study, monitoring, and early diagnosis of different visual pathologies that develop asymptomatically to advanced stages of pathology, such as age-related macular degeneration (ARMD), and that could go unnoticed if not adequately tested. In this study, we check the visual test developed for quantifying discrimination capacity in subjects with different ocular pathologies and seek to determine whether these ocular pathologies, which affect the retinal-image quality, cause any deterioration in the discrimination capacity and, consequently, in visual performance.