Matteoli S, Favuzza E, Mazzantini L, Aragona P, Cappelli S, Corvi A, Mencucci R
Department of Industrial Engineering, University of Florence, via di S. Marta 3, 50139 Florence, Italy.
Physiol Meas. 2017 Jul 26;38(8):1503-1512. doi: 10.1088/1361-6579/aa78bd.
In recent decades infrared thermography (IRT) has facilitated accurate quantitative measurements of the ocular surface temperature (OST), applying a non-invasive procedure. The objective of this work was to develop a procedure based on IRT, which allows characterizing of the cooling of the ocular surface of patients suffering from dry eye syndrome, and distinguishing among patients suffering from aqueous deficient dry eye (ADDE) and evaporative dry eyes (EDE).
All patients examined (34 females and 4 males, 23-84 years) were divided into two groups according to their Schirmer I result (⩽ 7 mm for ADDE and > 7 mm for EDE), and the OST was recorded for 7 s at 30 Hz. For each acquisition, the temperatures of the central cornea (CC) as well as those of both temporal and nasal canthi were investigated.
Findings showed that the maximum temperature variation (up to 0.75 ± 0.29 °C) was at the CC for both groups. Furthermore, patients suffering from EDE tended to have a higher initial OST than those with ADDE, explained by the greater quantity of the tear film, evenly distributed over the entire ocular surface, keeping the OST higher initially. Results also showed that EDE patients had an average cooling rate higher than those suffering from ADDE, confirming the excessive evaporation of the tear film.
Ocular thermography paves the way to become an effective tool for differentiating between the two different etiologies of dry eye syndrome.
近几十年来，红外热成像技术（IRT）通过一种非侵入性程序，实现了对眼表温度（OST）的精确定量测量。本研究的目的是开发一种基于IRT的程序，用于表征干眼症患者眼表的冷却情况，并区分水液缺乏型干眼症（ADDE）患者和蒸发过强型干眼症（EDE）患者。
所有接受检查的患者（34名女性和4名男性，年龄23 - 84岁）根据其Schirmer I试验结果（ADDE患者≤7毫米，EDE患者>7毫米）分为两组，并以30赫兹的频率记录7秒的眼表温度。每次采集时，均对中央角膜（CC）以及颞侧和鼻侧眼角的温度进行研究。
研究结果表明，两组患者的最大温度变化（高达0.75±0.29°C）均出现在中央角膜处。此外，EDE患者的初始眼表温度往往高于ADDE患者，这是因为泪膜量更大，均匀分布在整个眼表，使得初始眼表温度更高。结果还表明，EDE患者的平均冷却速率高于ADDE患者，证实了泪膜的过度蒸发。
眼热成像技术为区分干眼症综合征的两种不同病因提供了一种有效的工具。
