Perfusion and heat transfer in the canine prostate
A variety of thermally-based treatments for prostate-related diseases has motivated efforts to analyze heat transfer in the prostate. In order to develop an accurate heat transfer model of living tissue, the complex interaction of perfusion and heat transfer must be addressed. An initial step to quantifying the effect is to measure the normal perfusion level and response to thermal stimuli. Using the conventional microspheres method, the spatial and temporal heterogeneity in perfusion within canine prostates were quantified as well as the perfusion response to hyperthermic conditions. Besides the direct measurement of perfusion with microspheres, thermal diffusion methods infer perfusion by assuming the Pennes tissue heat transfer model. Simultaneous measurements of perfusion by both methods in the normothermic and hyperthermic canine prostates revealed disagreements. This was hypothesized to arise from the inability of the Pennes model to account for discrete thermally significant blood vessels. To test this, a heat transfer model of the thermal measurement technique in canine prostate tissue was developed. The perfusion heat transfer was modeled with discrete blood vessels based upon vascular viii parameters collected in canine prostates. This model was then analyzed numerically using finite element methods. Similar differences were shown by the numerical experiments. Comparison of the two different perfusion measurement methods provided insights into the utility of each method. Furthermore, the new perfusion heat transfer model can be used to replace the commonly adopted Pennes model. Overall, this dissertation provided insights into the areas of prostate perfusion, perfusion measurement methods, and heat transfer in perfused prostate tissue.