【摘要】 为了给重离子治癌装置的照射野均匀度的确定提供依据 ,从理论上研究了重离子照射野均匀度对细胞存活率的影响。以细胞存活率曲线的线性平方模型为基础 ,导出了受不均匀重离子照射野照射时的细胞存活率与剂量的关系式 ,利用这个关系式讨论了照射野均匀度对细胞存活率的影响。结果表明 ,受不均匀照射野照射时的细胞存活率要比受理想的均匀照射野照射时的细胞存活率大 ,均匀度越差细胞存活率越大 ;当实际照射野均匀度 >95%时 ,方可将实际的照射野作为理想的均匀照射野来处理。因此 ,重离子治癌装置的照射野均匀度应 >95%。同时指出 ,在对不同的实验室所得到的细胞存活率曲线进行比较时 ,应考虑不同的实验室的重离子照射野的均匀度的一致性更多还原

【Abstract】 In order to provide theoretical basis for the homogeneity request of heavy-ion irradiation field,the most important design parameter of the heavy-ion radiotherapy facility planned in IMP(Institute of Modern Physics),the influence of the homogeneity of heavy-ion irradiation field on the survival fraction of cells was investigated theoretically. A formula for survival fraction of cells irradiated by the un-uniform heavy-ion irradiation field was deduced to estimate the influence of the homogeneity of heavy-ion irradiation field on the survival fraction of cells. The results show that the survival fraction of cells irradiated by the un-uniform irradiation field is larger than that of cells irradiated by the uniform irradiation field,and the survival fraction of cells increases as the homogeneity of heavy-ion irradiation field decrease. Practically,the heavy-ion irradiation field can be treated as uniform irradiation field when its homogeneity is better than 95%. According to these results,design request for the homogeneity of heavy-ion irradiation field should be better than 95%. The present results also show that the agreement of homogeneity of heavy-ion irradiation field must be checked while comparing the survival fraction curves obtained by different laboratory.更多还原