Abstract
The external ear canal temperature (ECT) is very similar to the eardrum temperature (ET) as the core body temperature (CBT) at room-temperature. The body temperature measurement method in daily life using thermistor could be more safety the external ear canal than eardrum. However, ECT was affected by the ambient temperature (AT). Therefore, the aim of this study was to verify the new calibration method of ECT based on the dual heat flow method for CBT monitoring, and to develop the prototype earphone system using thermistor. Vitro experiment was performed using a cylindrical black-body to investigate the accuracy of the new calibration method. Vivo experiment was performed to validate the accuracy of CBT derived from ECT measured by prototype system in the 5 AT conditions (18, 23, 28, 33, 38 ℃). In vitro, the difference between the calibrated temperature using the cylinder inner temperatures and the blackbody temperature was 0.003 ± 0.068 ℃ (mean ± 1.96 standard deviation). In vivo, the difference between the calibrated CBT using the ECTs and the ET as a reference was < 0.001 ± 0.237 ℃. These results suggest that the derived CBT using prototype earphone might be the available index for CBT monitoring in daily life.
