CAJ | 학술논문

目的　探讨激光与生物组织之间的相互作用，建立估算生物组织热损伤深度的数学模型，为优化激光手术安全操作规范提供理论与实验的依据。方法　采用生物组织换热的数学模型——数学上称为多边界的Stefan问题，对激光作用下生物组织的热损伤过程进行数学模拟，并将该数值解与CO2激光对离体猪肌肉作用的实验数据相对比。结果　当CO2激光功率分别为1.50、3.15和8.01 W，每种功率进行两种不同作用时间（9～20 s）的情况下，用激光医学实验和数学模拟计算两种方法去确定猪肌肉组织的热损伤深度，两者相对偏差的平均值为3.60%，最大相对偏差值为5.59%。模拟计算不仅可以确定热损伤区的数值，还能得出一些重要的参数数据：例如相间边界的移动速度、相边界温度随时间的变化以及这些参数与功率的相互关系。结论　依据Vasiliev［1］的建模思想提出了热损伤过程的实用数学模型，其数值模拟结果与激光对生物组织热损伤的实验数据能较好地符合。该数学模拟还可为激光与生物组织相互作用的基础研究，提供纯激光外科实验难以得到的大量信息。
목적　탐토격광여생물조직지간적상호작용，건립고산생물조직열손상심도적 수학모형，위우화격광수술안전조작규범제공이론여실험적의거。 방법　채용생물조직환열적수학모형——수학상칭위다변계적Stefan문제，대 격광작용하생물조직적열손상과정진행수학모의，병장해수치해여CO2격광대리체저기육 작용적실험수거상대비。 결과　당CO2격광공솔분별위1.50、3.15화8.01 W，매충공솔진행량충불 동작용시간（9～20 s）적정황하，용격광의학실험화수학모의계산량충방법거학정저 기육조직적열손상심도，량자상대편차적평균치위3.60%，최대상대편차치위5.59%。모의 계산불부가이학정열손상구적수치，환능득출일사중요적삼수수거：례여상간변계적이동속 도、상변계온도수시간적변화이급저사삼수여공솔적상호관계。 결론　의거Vasiliev［1］적건모사상제출료열손상과정적실용수학모형 ，기수치모의결과여격광대생물조직열손상적실험수거능교호지부합。해수학모의환가위격 광여생물조직상호작용적기출연구，제공순격광외과실험난이득도적대량신식。
Objective　Laser-tissue interaction was investigated in order to determine the depth of thermal damage induced by CO2 laser irradiation. The r esults obtained could be used to pr ovide the theoretical and experimental bases for optimizing the safety operating rules of laser surgery. Methods　A mathematical model of heat transfer in biological tissues —the Stefan problem with multiple-interface from the point of view of mathem atics—was adopted to simulate the thermal damage processes in laser-irradiat ed tissues, and the numerical solutions were compared with the experimental data on thermal damage caused by CO2 laser for porcine hog muscle in vitro. Results　Using two methods, i.e., the mathematical simulation and las er surgery experiment the depth of thermal damage induced by laser irradiation i n biological tissues was determined. The CO2 laser power output was 1.50 W, 3 .15 W and 8.01 W, respectively, and irradiation time was 9-20 s. The avera ge value of relative deviation which represents the departure of the numerical s olution from the experimental result was 3.60%. The maximum value of relative deviation was 5.59%. The mathematica l simulating calculation was able to find out the thermal dam age depth not only, but also able to yield some i mportant data on parameters such as the phase-change interface velocity, time- dependent interface temperature, and their relationship with power output. Conclusions　The results of numerical simulation based on Vasilev's m odelling idea［1］ showed substantial agreement with the experimental data on thermal damage in laser-irradiated tissues. This mathematical simulation co uld also furnish the basic research on laser-tissue interactions with a large a mount of information which is difficult to obtain through the laser surgery expe riment.