Theoretical and experimental studies of vascular thermoregulation under hyperthermic conditions

Cuiye Chen, Purdue University

Abstract

In this thesis, theoretical and experimental studies of vascular thermoregulation in tissue temperature response to hyperthermia were presented. A new vascular model was developed based on which an analytical solution was obtained for the steady state tissue temperature distribution in pig kidney subjected to surface heating. The vascular model was further extended to numerically simulate the transient 3D tissue temperature distribution under various heating conditions. Theoretical predictions were substantiated through experimental measurements. Experiments were designed and performed using isolated pig kidneys subjected to surface heating in a water bath. LabVIEW programs were developed for data acquisition and control of the experiments. Parametric studies were performed to investigate the individual effects of the heating rate, the change rate and the time delay of blood perfusion on the tissue temperature response to hyperthermia. It was found that the heating rate, the magnitude and the time delay of blood perfusion in response to tissue temperature elevation, all have significant effects on tissue temperature oscillations. Under the surface heating, practically no sustained oscillations occurred, while volumetric heating, i.e., microwave heating, can induce significant sustained tissue temperature oscillations. It was concluded that to accurately predict the temperature response in the hyperthermia treatment of a particular tissue, the understanding of the specific blood perfusion change response to tissue temperature elevation is essential. Results from this study provide some insights into the mechanisms of vascular thermoregulation in living tissues.

Degree

Ph.D.

Advisors

Xu, Purdue University.

Subject Area

Mechanical engineering|Biophysics

COinS