Journal ArticleDOI
A New Simplified Bioheat Equation for the Effect of Blood Flow on Local Average Tissue Temperature
Sheldon Weinbaum,Latif M. Jiji +1 more
TLDR
A new simplified three-dimensional bioheat equation is derived to describe the effect of blood flow on blood-tissue heat transfer and shows that the vascularization of tissue causes it to behave as an anisotropic heat transfer medium.Abstract:
A new simplified three-dimensional bioheat equation is derived to describe the effect of blood flow on blood-tissue heat transfer. In two recent theoretical and experimental studies [1, 2] the authors have demonstrated that the so-called isotropic blood perfusion term in the existing bioheat equation is negligible because of the microvascular organization, and that the primary mechanism for blood-tissue energy exchange is incomplete countercurrent exchange in the thermally significant microvessels. The new theory to describe this basic mechanism shows that the vascularization of tissue causes it to behave as an anisotropic heat transfer medium. A remarkably simple expression is derived for the tensor conductivity of the tissue as a function of the local vascular geometry and flow velocity in the thermally significant countercurrent vessels. It is also shown that directed as opposed to isotropic blood perfusion between the countercurrent vessels can have a significant influence on heat transfer in regions where the countercurrent vessels are under 70-micron diameter. The new bioheat equation also describes this mechanism.read more
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Book ChapterDOI
Thermometry in Therapeutic Hyperthermia
T. V. Samulski,P. Fessenden +1 more
TL;DR: The delivery of local and regional therapeutic hyperthermia in clinical practice proves to be a difficult challenge because the difficulty is associated not so much with excessive heating of normal tissue as with achieving a minimum, uniform therapeutic temperature in the target tissue volume.
Journal ArticleDOI
Interstitial hyperthermia treatment of countercurrent vascular tissue: a comparison of Pennes, WJ and porous media bioheat models.
Saied Hassanpour,Ahmad Saboonchi +1 more
TL;DR: A mathematical model is developed for the heat transfer in a cylindrical medium containing parallel counter-current pairs of small vessels with characteristics as much as possible similar to those of living tissues and results revealed that the heat affected zone at hyperthermic condition predicted by all three models are similar.
Journal ArticleDOI
Comparison of numerical calculations with phantom experiments and clinical measurements.
Keith D. Paulsen,Michael P. Ross +1 more
TL;DR: Comparisons between model predictions and measurements show that quantitative agreement occurs in phantoms containing moderate complexities in heterogeneity, but that only qualitative agreement appears possible in clinical treatments, and suggest that the lack of blood flow information may contribute as much, if not more, to the uncertainties in the clinical predictions.
Journal ArticleDOI
Finite element model to study temperature distribution in skin and deep tissues of human limbs.
TL;DR: A finite element model has been proposed to study temperature distribution in skin and deep tissues of human limbs and the relation of tissue temperature with the parameters like atmospheric temperature, rate of evaporation, thickness of tissues layers and shape of the limb.
Book ChapterDOI
Physics of Laser-Induced Hyperthermia
TL;DR: The rationale for the use of a new modality such as laser-induced hyperthermia in the treatment of human neoplasm is based on a broad spectrum of research as discussed by the authors.