Dry Eye Diagnosis Using Ocular Surface Thermography During a Short Period of Sustained Eye Opening

Abstract

Purpose: : The ocular surface temperature of dry eyes has been reported to be significantly lower than that of normal eyes in studies conducted using general thermography techniques during sustained eye opening. We developed a thermography device specialized for the ocular surface, Ocular Surface Thermographer (OST, TOMEY Co, Japan), and investigated the possibility of diagnosing dry eye by measuring the ocular surface temperature during a short period of sustained eye opening.

Methods: : A total of 90 cases, 30 each with definite dry eye (DD), suspected dry eye (DS) and normal eyes (N), were recruited based on the 2006 Japanese dry eye diagnostic criteria. The ocular surface temperature was recorded using OST during a ten-second period of sustained eye opening after subjects had closed their eyes for five seconds. The average temperature of a 4 mm circle at the center of the cornea was calculated each second, and the change in temperature per second (Δ°C/s) for each one-second time interval was compared between groups.

Results: : The corneal surface temperatures of the three groups were not significantly different immediately after opening the eye. The Δ°C/s values were -0.015±0.078, -0.063±0.085, and -0.082±0.084 (p=0.0063, ANOVA) at 0-1 seconds and 0.000±0.063, -0.054±0.056, and -0.066±0.053 (p<0.0001, ANOVA)at 1-2 seconds for the N, DS, and DD groups, respectively. From 0 to 5 seconds after eye opening, significant differences were observed between the Δ°C/s values of the N, DS, and DD groups and the greatest difference between the groups was observed at 1-2 seconds. When the cut-off value for total temperature change in the initial three-second period of sustained eye opening was designated as -0.07°C, the sensitivity was 86.7% and the specificity was 70.0%.

Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • cornea: tears/tear film/dry eye • cornea: clinical science