유한 요소 시뮬레이션을 이용한 이중 매질 심부 체온계의 정확도 평가

Abstract

Continuous body temperature monitoring is useful and essential in diverse medical procedures such asinfection onset detection, therapeutic hypothermia, circadian rhythm monitoring, sleep disorder assessment, andgynecological research. However, the existing thermometers are too invasive or intrusive to be applied to long-termbody temperature monitoring. In our previous study, we invented the bi-medium deep body thermometer which cannoninvasively and continuously monitor deep tissue temperature. And the ratio of thermal resistances expressed asK-value should be obtained to estimate body temperature with the thermometer and it can be different under variousmeasurement environments. Although the device was proven to be useful through preliminary simulation test andsmall group of human study, the experimental environment was restrictive in our previous approach. In this study,a finite element simulation was executed to obtain the K-value and evaluate the accuracy of bi-medium thermometerunder various measurement environments. In addition, K-value estimation equation was developed by analyzing theinfluence of 5 measurement environmental factors (medium length, medium height, tissue depth, blood perfusionrate, and ambient temperature) on K-value. The results revealed that the estimation accuracy of bi-medium deepbody thermometer based on computer simulation was very high (RMSE < 0.003oC) in various measurement environments. Also, bi-medium deep body thermometer based on K-value estimation equation showed relatively accurateresults (RMSE < 0.3oC) except for one case. Although the K-value estimation technology should be improved formore accurate body temperature estimation, the results of finite element simulation showed that bi-medium deepbody thermometer could accurately measure various tissue temperatures under diverse environments.