应用不同深度和大小的乳房肿瘤低温治疗评估皮肤表面热对比度的三维数值。
Three-dimensional numerical evaluation of skin surface thermal contrast by application of hypothermia at different depths and sizes of the breast tumor.
机构信息
Department of Mechanical Engineering, State University of Maranhao, Sao Luis, Brazil.
Department of Mechanical Engineering, State University of Maranhao, Sao Luis, Brazil; Post-Graduate Program in Mechanical Engineering, Federal Institute of Education, Science and Technology of Maranhao, Sao Luis, Brazil.
出版信息
Comput Methods Programs Biomed. 2023 Jun;236:107562. doi: 10.1016/j.cmpb.2023.107562. Epub 2023 Apr 30.
BACKGROUND AND OBJECTIVE
Thermal procedures can provide improvements in the thermal contrast of thermographic images in an attempt to diagnose early cases of breast cancer. This work aims to analyze the thermal contrast of different stages and depths of breast tumors from hypothermia treatment using an active thermography analysis. The influence of variation in metabolic heat generation and adipose tissue composition on thermal contrasts is also analyzed.
METHODS
The proposed methodology was based on the solution of the Pennes equation for a three-dimensional model similar to the real anatomy of the breast by commercial software COMSOL Multiphysics. The thermal procedure consists of three steps: Stationary, hypothermia and thermal recovery. During hypothermia, the boundary condition of the external surface was replaced by a constant temperature of 0, 5, 10, and 15 C, simulating a gel pack, for cooling times of up to 20 min. In the thermal recovery, after the removal of the cooling, the breast was submitted again to the condition of natural convection on the external surface.
RESULTS
Thermal contrasts in superficial tumors, for all hypothermia resulted in improvements in thermographs. For smallest tumor, the use of high resolution and sensitive thermal imaging cameras to acquire this thermal change may be necessary. For tumor of diameter of 10 cm, cooling from 0 C can increase the thermal contrast by up to 136% compared to the passive thermography. Analyzes with deeper tumors showed very small temperature variations. Even so, the thermal contrast gain in cooling at 0 C for the tumor with a diameter of 1 cm reached 37% in relation to passive thermography.
CONCLUSIONS
Thus, this work contributes as an important tool in the analysis of the appropriate use of hypothermia for different cases in early stages of breast cancer, considering that long times are needed to obtain the best thermal contrast.
背景与目的
热疗方法可以提高热成像的热对比度，以尝试诊断早期乳腺癌病例。本研究旨在通过主动热成像分析，分析不同阶段和深度的乳腺肿瘤在低温治疗下的热对比度。还分析了代谢产热和脂肪组织组成的变化对热对比度的影响。
方法
所提出的方法基于使用商业软件 COMSOL Multiphysics 对类似于乳房真实解剖结构的三维模型求解 Pennes 方程。热疗过程包括三个步骤：稳定、低温和热恢复。在低温过程中，通过将外部表面的边界条件替换为 0、5、10 和 15°C 的恒定温度，模拟凝胶包，来冷却长达 20 分钟。在热恢复中，冷却去除后，乳房再次处于外部表面自然对流的条件下。
结果
所有低温处理后的浅层肿瘤的热对比度都得到了改善。对于最小的肿瘤，可能需要使用高分辨率和高灵敏度的热成像相机来获取这种热变化。对于直径为 10cm 的肿瘤，与被动热成像相比，冷却至 0°C 可将热对比度提高高达 136%。对更深层肿瘤的分析显示出非常小的温度变化。即便如此，直径为 1cm 的肿瘤在 0°C 冷却时，与被动热成像相比，热对比度的增益仍达到了 37%。
结论
因此，这项工作为分析不同情况下低温治疗在乳腺癌早期的适当应用提供了重要工具，因为需要较长时间才能获得最佳的热对比度。
Zotero 插件