Advancing the diagnosis of Dry Eye Syndromedevelopment of dynamic, automated tear film Break-Up assessment

Abstract

Dry Eye Syndrome (DES) is a common disorder of the tear film which affects a significant sector of the population, impacting on quality of life. The diagnosis of this condition is difficult due to its multifactorial etiology, so there are a wide number of tests to evaluate different aspects of the tear film. Among the different tests available, the Break-up Time test (BUT) is a widely used measure to evaluate the quality and stability of the tear film on the ocular surface. It consists in measuring the time elapsed since the last blink until the tear film break-up, that is, the appearance of dark areas related to a thinning of the tear film on the surface of the eye. Besides the time, there are several break-up features such as the location, shape, size and dynamics of the breakup areas, which could affect to dry eye severity. However, the BUT test is affected by low repeatability mainly due to a subjective appreciation of the dark spots, the differences among the experts, and the variability of the tear film. Furthermore, the characterization by hand of break-up areas is a tedious and time consuming task. The automation of the break-up assessment would reduce its subjective character, allowing a more accurate evaluation of tear film stability. This work presents a novel methodology for a fully automatic assessment of the tear film break-up. The proposed methodology allows a quantitative, qualitative analysis of tear film instability, as an extension of BUT measurement, which is focused only on time. It provides accuracy results that are in the same ranges as the experts themselves. Therefore, the automated breakup assessment saves time for experts providing unbiased results which are not affected by subjective factors.