Investigating the subjective cooling effect of eyelid cleansing gel on eyelid and ocular surface temperature

To investigate if the application of Blephagel, an eyelid cleansing gel, causes subjective and/or objective cooling effects by measuring ocular symptomology and temperature.

Twenty-five healthy subjects underwent baseline non-invasive temperature measurements on the closed upper eyelid (centrally, nasally, and temporally) and ocular surface temperature (OST) on both eyes using an infrared camera. A standard application of Blephagel was then applied to the closed upper eyelid and eyelashes with a sterile cotton-wool to one eye selected at random. Temperature measures were then repeated on both eyes after 30-60, 120-150, and 180-210 s. At each interval, subjects rated the comfort and any cooling sensation of each eye on a 0-10 scale.

After application of the gel, there was a significant difference in temperature at all locations on the eyelid between the test and control eyes over time (F = 9.322, p < 0.001). Post hoc analysis revealed this was significant from 30 to 60 s interval (36.3 ± 1.1 °C versus 37.2 ± 0.7 °C; p < 0.001) and the 120-150 s interval (36.8 ± 0.8 °C versus 37.2 ± 0.6 °C; p < 0.001). There was no significant variation between the OST locations over time (F = 3.350, p = 0.07). With respect to symptoms, there was a significant increase in cooling sensation in the test eye compared to the control eye over time (F = 10.438, p < 0.001), that remained throughout the experiment.

Blephagel produces a reduction in temperature of the eyelids that is accompanied with a subjective cooling sensation.