中文摘要：

目的探讨激光在组织中的传输规律，为光动力学治疗计划的制定打下基础。方法建立可同时求解生物组织内三维激光场、光敏剂浓度场及温度场发展过程的Monte Carlo计算方法，以临床上常见的甲状腺癌的治疗过程为例进行模拟。结果两种典型激光照射方式即从光纤端面或侧面出射所引起的光动力学反应和热效应分布存在明显不同，在临床上有不同价值。结论计算结果有助于更好地理解光动力学治疗中组织内的基础光热质传输机制，本文方法为光动力学治疗计划的拟定建立了相对完整的理论基础。

英文摘要：

Objective To interprete the transport of laser in tissue and for establishing the theoretical model for treatment planning of photodynamic therapy. Methods The Monte Carlo method was established to simultaneously simulate the three dimensional transient fields of laser, concentration of photosensitive agent and temperature in living tissues. The commonly encountered eases on treating thyroid gland tumor in clinics were investigated. Results The photodynamie reaetion and thermal effect induced by two typical laser irradiations from either tip of laser fiber or side wall were distinctly different, which can fulfill various specific clinical requirements. Conclusion The obtained results would help better understand the fundamental optical-thermalmass transport processes during laser tissue interstitial photodynamie therapy. The present method provides a. relatively complete theoretical foundation for treatment planning in a photodynamic therapy.