Endocrine Abstracts

Infrared Thermography (IT) is a non-invasive method and complementary to other diagnostic techniques to identify inhomogeneity of the thermal emission of the skin. We used IT (InfRec R500, Nippon Avionics Co.; 640×480 pixel, spatial resolution 0,87 mrad, sensitivity 0.03°C at 30°C, accuracy ±1°C) to assess the variations of skin temperature of the neck region: higher mean temperature, greater thyroid function. Primary outcome of this study was to compare the temperature of the neck skin superficially to the thyroid gland and Resting Energy Expenditure (REE) measured by indirect calorimetry. Secondary aims were to analyze the correlation between thermographic values and: 1) BMI 2) TSH 3) total cholesterol. Eighty patients (BMI=33.02±5.94 kg/m²; age 49.45±15.12 years; 53 females and 27 males) recruited in the outpatient setting were studied. Neck skin temperature correlated directly with REE (r=0.34; P-value<0.01) and reversely with BMI (r=−0.27; P-value<0.01). TSH and total cholesterol were evaluated only in 25 subjects. A weak, not significant, direct correlation (r=0.21; P-value=0.14) and a significant inverse correlation (r=−0.23; P-value<0.01), respectively, was found. Our preliminary results suggest that infrared thermography could represent a useful tool in clinical thyroidology as it is quick, safe for the patient and the operator, easy to perform and that can provide important information not only on the structure and on the presence of nodules but also on the functionality of the thyroid gland. Furthermore, the association of this technique with the measurement of the REE with indirect calorimetry can provide a valuable tool in the diagnosis of thyroid dysfunction, especially in subclinical and overt hypothyroidism.