dc.contributor.author Gowrishankar, T. R. dc.contributor.author Stewart, Donald A. dc.contributor.author Martin, Gregory T. dc.contributor.author Weaver, James C. dc.date.accessioned 2013-01-04T21:09:37Z dc.date.issued 2004 dc.identifier.citation Gowrishankar, T.R., Donald A. Stewart, Gregory T. Martin, and James C. Weaver. 2004. Transport lattice models of heat transport in skin with spatially heterogeneous, temperature-dependent perfusion. BioMedical Engineering OnLine 3:42. en_US dc.identifier.issn 1475-925X en_US dc.identifier.uri http://nrs.harvard.edu/urn-3:HUL.InstRepos:10139274 dc.description.abstract Background: Investigation of bioheat transfer problems requires the evaluation of temporal and spatial distributions of temperature. This class of problems has been traditionally addressed using the Pennes bioheat equation. Transport of heat by conduction, and by temperature-dependent, spatially heterogeneous blood perfusion is modeled here using a transport lattice approach. Methods: We represent heat transport processes by using a lattice that represents the Pennes bioheat equation in perfused tissues, and diffusion in nonperfused regions. The three layer skin model has a nonperfused viable epidermis, and deeper regions of dermis and subcutaneous tissue with perfusion that is constant or temperature-dependent. Two cases are considered: (1) surface contact heating and (2) spatially distributed heating. The model is relevant to the prediction of the transient and steady state temperature rise for different methods of power deposition within the skin. Accumulated thermal damage is estimated by using an Arrhenius type rate equation at locations where viable tissue temperature exceeds $42^\circ C$. Prediction of spatial temperature distributions is also illustrated with a two-dimensional model of skin created from a histological image. Results: The transport lattice approach was validated by comparison with an analytical solution for a slab with homogeneous thermal properties and spatially distributed uniform sink held at constant temperatures at the ends. For typical transcutaneous blood gas sensing conditions the estimated damage is small, even with prolonged skin contact to a $45^\circ C$ surface. Spatial heterogeneity in skin thermal properties leads to a non-uniform temperature distribution during a 10 GHz electromagnetic field exposure. A realistic two-dimensional model of the skin shows that tissue heterogeneity does not lead to a significant local temperature increase when heated by a hot wire tip. Conclusions: The heat transport system model of the skin was solved by exploiting the mathematical analogy between local thermal models and local electrical (charge transport) models, thereby allowing robust, circuit simulation software to obtain solutions to Kirchhoff's laws for the system model. Transport lattices allow systematic introduction of realistic geometry and spatially heterogeneous heat transport mechanisms. Local representations for both simple, passive functions and more complex local models can be easily and intuitively included into the system model of a tissue. en_US dc.language.iso en_US en_US dc.publisher BioMed Central en_US dc.relation.isversionof doi://10.1186/1475-925X-3-42 en_US dc.relation.hasversion http://www.ncbi.nlm.nih.gov/pmc/articles/PMC544831/pdf/ en_US dash.license LAA dc.title Transport Lattice Models of Heat Transport in Skin with Spatially Heterogeneous, Temperature-Dependent Perfusion en_US dc.type Journal Article en_US dc.description.version Version of Record en_US dc.relation.journal BioMedical Engineering OnLine en_US dash.depositing.author Weaver, James C. dc.date.available 2013-01-04T21:09:37Z dash.affiliation.other HMS^Health Sciences and Technology en_US dc.identifier.doi 10.1186/1475-925X-3-42 * dash.contributor.affiliated Weaver, J
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