目的:近年來，癌病已成為人類死亡的主要病因，因此科學家正頃全力研究癌病的起因、防治、與診療。目前清華大學正利用清華水池式反應器，進行硼中子捕獲治療法(BoronNeutron Capture Therapy，簡稱BNCT)之中子屏蔽、藥物研發、生物實驗、劑量評估等研究。本文之目的，即在於評估硼中子捕獲治療的輻射劑量與品質。組織中，再以熱(或超熱)中子束照射，使中子和硼發生核反應，釋出高游離密度與短射程的粒子輻射，有效殺死腫瘤組織而不影響正常組織。其所造成吸收劑量的主要貢獻有α粒子劑量及鋰-7重核粒子劑量。若代入等效劑量的定義，可求得腫瘤組織的有效射質因數Q;若代入等值劑量的定義，即可求得正常組織及腫瘤組織的有效輻射加權因數W□。關係，在高濃度時則呈線性正比的關係，當腫瘤組織含硼濃度太低時，有效射質因數會降低，使得腫瘤組織與正常組織的輻射致死效應相當，而減低BNCT的治療效益。factor)、等值劑量(equivalent dose)、有效輻射加權因數(effective radiation weightingfactor)的評估程式，由外部輸入或利用系統內建的中子能譜、中子通量率、及腫瘤組織之含硼濃度等條件，進行各種核反應引起的輻射劑量與輻射品質的探討。

　　　　　Purpose: A beam port of epithermal neutrons at Tsing Hua Open Pool Reactor(THOR) was recently built. This port was designed for basic research on boron neutroncapture therapy (BNCT). The research team consisted of radiobiologists,pharmaceutical chemists, medical scientists, nuclear engineers, and healthphysicists. The dosimetry group took the responsibility for the assessment oftumor/normal tissue biological doses. Radiation dose and quality were assessed inthis work.to the patient. Isotope will accumulate in tumor mostly. Following the irradiationof an epithermal (thermal) neutron beam. □B(n,α)□Li nuclear reactions occur andshort-range and high LET particles emit. These particles kill the tumor cells butunharm the normal tissues. We focus our study on equivalent doses, effective qualityfactors (Q) and effective radiation weighting factors (W□) by the dosimetric model.concentration was nonlinear. At such concentration, when decreased, the radiationeffects for tumor and normal tissues were approximately the same. The therapeuticeffectiveness by BNCT was decreased. As boron concentration increased the relationbecame linear and the therapeutic effectiveness was better.from input of boron concentration, neutron flux and energy, irradiation geometry andtime. Results were analyzed as a function of separate and combined input factors.Optimal irradiation conditions were recommended for future clinical application.