Evaluation of Ocular Surface Temperature in Glaucoma Patients Using a Non-Contact Infrared Thermometer

Aim: To evaluate the clinical relevance of ocular surface temperature (OST) measured by non-contact infrared thermometry in glaucoma patients and to determine its diagnostic performance alone and within a multivariable predictive model.Material and Methods: In this cross-sectional study, 100 glaucoma patients and 90 healthy controls underwent comprehensive ophthalmological examination. Corneal, ocular surface, and body temperatures were measured using a non-contact infrared thermometer at a fixed 5-cm distance under controlled room temperature (25 °C). Intraocular pressure (IOP), central corneal thickness (CCT), cup-to-disc ratio, pseudoexfoliation (PEX) status, and topical antiglaucomatous treatment characteristics were recorded.Results: Corneal and globe temperatures were significantly lower in glaucoma patients than in controls (33.38 ± 0.57 °C vs. 33.82 ± 0.68 °C and 36.09 ± 0.24 °C vs. 36.33 ± 0.35 °C; p = 0.001 for both), whereas body temperature did not differ (p = 0.605). Cup-to-disc ratio, IOP, age, and lower corneal temperature were independently associated with glaucoma, while PEX status and CCT were not significant predictors. Corneal temperature alone showed limited discriminative ability (AUC = 0.685), whereas the combined multivariable model demonstrated excellent diagnostic performance (AUC = 0.974).Conclusion: Glaucoma is associated with significantly reduced ocular surface temperatures, which may reflect altered ocular physiology reported in glaucoma. Although OST alone has limited diagnostic utility, its integration with established clinical parameters provides strong discriminative performance. Non-contact infrared thermometry may serve as a simple, non-invasive adjunct biomarker within multiparametric glaucoma assessment and monitoring.