Electronic facial thermography: an analysis of asymptomatic adult subjects.

Vascular heat emissions that present on the human face can provide physiologic indicators of underlying health or disease. Electronic thermography may serve as a nonionizing, noninvasive alternative for solving diagnostic problems. This study was designed to quantify normal values of vascular heat emissions of the face. Electronic thermograms were taken of 102 subjects using an Agema 870 unit, at 0.1 degree C accuracy, under controlled conditions. Results indicated a high degree of mean thermal symmetry about the face. Using frontal and lateral electronic thermogram projections, the mean temperatures of 25 selected right-versus-left-side anatomic zones were within 0.1 degree C of each other. Analysis of frontally and laterally projected electronic thermograms also produced a new mapping of thermally distinct facial zones. Of greatest importance, the right-versus-left-side thermal differences (delta T) between many specific facial regions for individual subjects were demonstrated to be much smaller (< 0.4 degrees C) than previously reported delta T values of the same facial regions in a wide variety of chronic disorders. These differences in delta T values between asymptomatic subjects and patients with various facial pain syndromes may prove to be useful thresholds for determining normal versus abnormal facial thermograms.