Chen S S, Wright N T, Humphrey J D
Department of Mechanical Engineering, University of Maryland, Baltimore 21250, USA.
IEEE Trans Biomed Eng. 1998 Oct;45(10):1234-40. doi: 10.1109/10.720201.
Optimization of clinical heat treatments for various pathologies requires accurate numerical modeling of the heat transfer, evolution of thermal damage, and associated changes in the material properties of the tissues. This paper presents two phenomenological equations that quantify time-dependent thermal damage in a uniaxial collagenous tissue. Specifically, an empirical rule-of-mixtures model is shown to describe well heat-induced axial shrinkage (a measure of underlying denaturation) in chordae tendineae which results from a spectrum of thermomechanical loading histories. Likewise an exponential decay model is shown to describe well the partial recovery (e.g., renaturation) of chordae when it is returned to body temperature following heating. Together these models provide the first quantitative descriptors of the evolution of heat-induced damage and subsequent recovery in collagen. Such descriptors are fundamental to numerical analyses of many heat treatments because of the prevalence of collagen in many tissues and organs.
针对各种病症优化临床热疗需要对热传递、热损伤演变以及组织材料特性的相关变化进行精确的数值模拟。本文提出了两个唯象方程，用于量化单轴胶原组织中随时间变化的热损伤。具体而言，一个经验混合律模型被证明能很好地描述腱索因一系列热机械加载历史而产生的热诱导轴向收缩（潜在变性的一种度量）。同样，一个指数衰减模型被证明能很好地描述腱索在加热后恢复到体温时的部分恢复（例如复性）情况。这些模型共同提供了热诱导损伤演变以及胶原蛋白后续恢复的首个定量描述。由于胶原蛋白在许多组织和器官中普遍存在，此类描述对于许多热疗的数值分析至关重要。
