Ge M Y, Shu C, Yang W M, Chua K J
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore.
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore.
J Therm Biol. 2017 Feb;64:92-99. doi: 10.1016/j.jtherbio.2017.01.006. Epub 2017 Jan 21.
In this paper, the three-dimensional thermal effects of a clinically-extracted vascular tissue undergoing cryo-freezing are numerically investigated. Based on the measured experimental temperature field, the numerical results of the Pennes bioheat model combined with the boundary condition-enforced immersed boundary method (IBM) agreed well with experimental data with a maximum temperature discrepancy of 2.9°C. For simulating the temperature profile of a tumor sited in a dominantly vascularized tissue, our model is able to capture with ease the thermal effects at specified junctions of the blood vessels. The vascular complexity and the ice-ball shape irregularity which cannot be easily quantified via clinical experiments are also analyzed and compared for both two-dimensional and three-dimensional settings with different vessel configurations and developments. For the three-dimensional numerical simulations, a n-furcated liver vessels model from a three-dimensional segmented volume using hole-making and subdivision methods is applied. A specific study revealed that the structure and complexity of the vascular network can markedly affect the tissue's freezing configuration with increasing ice-ball irregularity for greater blood vessel complexity.
本文对临床提取的血管组织进行冷冻时的三维热效应进行了数值研究。基于实测的实验温度场，结合边界条件强制浸入边界法（IBM）的彭尼斯生物热模型的数值结果与实验数据吻合良好，最大温度差异为2.9°C。为了模拟位于血管丰富组织中的肿瘤的温度分布，我们的模型能够轻松捕捉血管特定连接处的热效应。还针对具有不同血管配置和发育情况的二维和三维设置，分析并比较了难以通过临床实验轻易量化的血管复杂性和冰球形状不规则性。对于三维数值模拟，应用了通过打孔和细分方法从三维分割体积中得到的n叉状肝血管模型。一项具体研究表明，血管网络的结构和复杂性会显著影响组织的冷冻形态，血管复杂性越高，冰球不规则性增加。
