Ocular-surface temperature modification by cataract surgery

PURPOSE: To analyze ocular-surface temperature changes after microincision cataract surgery and to correlate them with surgical, clinical, and laboratory parameters. SETTING: Ophthalmology Unit, Saint Orsola-Malpighi Hospital, Bologna, Italy. DESIGN: Prospective case series. METHODS: Patients affected by monolateral senile cataract were examined preoperatively and 7 days and 28 days postoperatively. Infrared thermography was used to measure the temperature soon after eye opening, the temperature after 10 seconds of sustained eye opening, and the difference between these 2 values in the central cornea, nasal limbus, and temporal limbus. The Ocular Surface Disease Index (OSDI), Schirmer test, vital staining, tear breakup time (TBUT), conjunctival scraping cytology, exudated tear-serum albumin, and laser flare-cell meter examinations were performed. RESULTS: The study comprised 26 patients (10 men, 16 women). The temperature changed significantly after surgery. The temperature soon after eye opening showed cooling in the central cornea and nasal limbus and heating in the temporal limbus. The temperature after 10 seconds of sustained eye opening minus the temperature soon after eye opening increased in all regions. The temperature after 10 seconds of sustained eye opening minus the temperature soon after eye opening in the central cornea was inversely related to the OSDI and directly related to TBUT. The temperature soon after eye opening increased in the temporal limbus and was directly related to inflammatory indices. CONCLUSIONS: The ocular-surface temperature changed after cataract surgery depending on the region analyzed. The cooling in the central cornea could be related to the increased tear-film instability. The heating in the temporal limbus could be related to postoperative inflammation.