Thermal Modeling of Vascular Patterns and Their Impact on Interstitial Heating Technology and Temperature Monitoring

Abstract

In interstitial hyperthermia we rely for temperature measurements on thermocouples placed either inside the catheter lumen and/or a limited distance from the catheters. It would be very helpful if this limited spatial temperature information could be extended through use of reliable thermal models to obtain and control the three-dimensional (3-D) temporal temperature distribution. Needless to say, these models could also be used for pretreatment planning purposes. A prerequisite of a thermal model for biological tissues is that it describes conductive and convective heat transport adequately, with emphasis on the latter as it has long been established that this is the predominant heat transfer mode. In nearly all papers on interstitial hyperthermia, the contribution of convective heat transport has been taken into account according to the proposal of Pennes (1948), i.e., the conventional bioheat transfer equation. However, consensus has been achieved (Valdagni et al. 1990) on the necessity of including at least a large vessel description as such vessels are important structures causing underdosage.