Relationship Between Corneal Temperature and Finger Temperature

BACKGROUND: Because the temperature of the body surface depends largely on local blood flow, temperature measurements might provide information on the latter. OBJECTIVE: To evaluate the relationship between corneal temperature and finger temperature. METHODS: Corneal, finger, and body core temperatures were measured in a relatively unselected population of 266 white persons. Excluded were persons taking topical eye medication or with corneal inflammatory signs. Corneal and finger temperatures were measured on 1 randomly selected side of the body by means of a noncontact infrared thermometer. As a measure of body temperature, the tympanic temperature was measured by means of a noncontact infrared ear thermometer. A total of 124 females and 142 males were examined. RESULTS: A correlation analysis in a least squares regression model was highly significant (R = 0.67; P<.001), with corneal temperature as the dependent variable and environmental, tympanic, and finger temperatures and age and sex as predicting variables. All variables contributed significantly to prediction of the corneal temperature. The corrected mean corneal temperature after adjusting for environmental, tympanic, and finger temperatures and for age of participants was 0.16 degrees C higher in male participants (P = .002). CONCLUSIONS: Corneal temperature correlates with finger temperature even after adjusting for environmental and tympanic temperatures and for the age and sex of participants. A possible cause for these findings are some parallelisms in blood-flow regulation in the finger and the eye.