Temperature and heat flux density of the eye surface in healthy individuals with different subfoveal thickness of the choroid

Abstract Purpose To study the temperature and heat flux (HF) density of the ocular surface of healthy individuals depending on the thickness of the choroid. Methods This pilot study included 22 healthy individuals (44 eyes). The age of the studied healthy individuals ranged from 18 to 86 years. In all cases, measurement of temperature and HF density were performed on the outer surface of the cornea of both eyes. A thermoelectric device was used to measure epibulbar temperature and HF density. Optical coherence tomography was performed to determine the subfoveal thickness of the choroid. Results Mean room temperature during examination sessions was 21.5 ± 0.8°C. In addition, mean temperature of the external ocular surface and mean HF density from the human eye were 34.7 ± 0.7°C and 7.5 ± 1.2 mW/cm 2 , respectively. The thickness of the choroid in healthy individuals averaged 307 ± 37 μm. There was a positive correlation between the thickness of the choroid with the heat flux density of the eye (r = 0.6; p = 0.000) in contrast to the temperature of the cornea ( r = 0.2; p = 0.1). Conclusions In healthy people, the density of the heat flux of the eye on the surface of the cornea depends on the subfoveal thickness of the choroid, in contrast to the temperature of the outer surface of the eye.