Abstract:

Objective To explore the relationship between temperature of cornea on ocular surface and stability of tear film. Methods A total of 94 patients with results of SchirmerⅠ test >10 mm/5 min were enrolled, and were divided into dry eye group （n=48）and non-dry eye group （n=46）based on dry eye complaints and results of break up time (BUT) test. New corneal topography was adopted to take the division photos of tear film, and infrared thermometer was used to measure temperature of cornea on ocular surface. The relationship between the stability of tear film and temperature of cornea on ocular surface was analysed. Results The grades of tear film images in dry eye group were significantly higher than those in non-dry eye group (P<0.01). The grades of tear film images were negatively correlated with BUT results (r=－0.752，P=0.00). By grades of tear film images, the average temperature of cornea on ocular surface of grade 0, gradeⅠ, grade Ⅱ and grade Ⅲ was (32.386±0.826 2) ℃, (34.084±1.373 3) ℃, (34.980±1.331 5) ℃ and (35.709±0.744 9) ℃ respectively, with significant differences among all grades （P<0.01）. Conclusion New corneal topography can reveal the stability of tear film. Higher temperature of cornea on ocular surface may cause instability of tear film, which is one of the major causes for dry eye.

Key words: temperature of cornea on ocular surface, stability of tear film, new corneal topography, evaporative dry eye