Ocular Surface Temperature in DED under Natural Non-Controlled Blinking Conditions

Abstract

Infrared (IR) thermography is a tool to non-invasively assess the tear film temperature. The aim was to analyze ocular surface temperature (OST) variations in dry eye disease (DED) and control eyes under natural non-controlled blinking conditions. Imaging was performed with a thermal camera (FLIR Systems Inc.) at 30 Hz framerate in 79 participants (39 DED (62.5% women, average age 48 ± 20 years) and 40 control (46.2 % women, average age 38 ± 13 years)) using non-contact IR thermography camera. Data acquisitions were performed in natural blinking conditions for 40 s. IR images were analyzed using a custom algorithm that calculates the OST indexes: mean OST, OST at the start and at the end, minimum and maximum OST, and tear evaporation rate (TER). No significant differences were found between groups in any thermal parameter analyzed (paired comparisons t-test, p > 0.05). In conclusion, the findings of this study did not reveal significant differences between DED and control eyes under natural non-controlled blinking conditions. However, the presence of clinical signs in the control group may affect the results, highlighting the role of DED diagnosis criteria.