目的 比较国产与进口直线加速器实施前列腺癌调强放射治疗的剂量学特点。方法 随机选取25例前列腺癌患者， 分别设计基于国产及进口直线加速器两组特定射野固定钨门静态调强（Intensity Modulated Radiation Therapy，IMRT）计 划，通过DVH读取分析两组计划靶区及各器官的剂量学参数，并通过比较机器跳数（MU）及剂量验证通过率，评估计划 的实施效率及准确性。结果 两组计划均实现处方剂量对靶区的较好覆盖，其中除D2%、D5%进口组优于国产组且差异有统 计学意义（P<0.05）外，其他差异均无统计学意义丨在正常器官保护上，国产组膀胱和直肠的V20均优于进口组，而在高 剂量区域，进口组优势随剂量升高体现出逐渐增加的趋势丨对于股骨头，国产组V30优于进口组，而进口组V40、V50优于国 产组，但仅右侧股骨头的V50差异有统计学意义（t=-2.27，P=0.03）。国产组计划验证通过率明显优于进口组（t=-9.89， P=0.00），且机器跳数相较于进口组减少了19.5%。结论 国产与进口直线加速器在实施前列腺癌调强放射治疗中均能实现 较好的靶区剂量分布，虽然国产加速器在危及器官高剂量照射体积偏高，但均达到了临床剂量要求，结合国产设备的应用 情况，可用于不同级别医院的前列腺癌调强放疗。

Objective To compare the dosimetric characteristics of intensity modulated radiotherapy (IMRT) for prostate cancer between domestic and imported linear accelerators. Methods A total of 25 patients with prostate cancer were randomly selected. The IMRT plans based on the domestic and imported linear accelerators were designed respectively. The dosimetric parameters of target area and organs at risk in the two groups were analyzed by DVH. The passing rate was verified by comparing the monitor unit (MU) and the dose, and the efficiency and accuracy of the plans were evaluated. Results The target area was well covered by prescription dose in both groups. There was no significant difference between the two groups except that D2% and D5% imported group were better than domestic group (P<0.05). In terms of normal organ protection, the V20 of bladder and rectum in domestic group were better than that in the imported group, while in high dose area, the advantage of imported group increased gradually with the increase of dose. For the femoral head, the V30 in domestic group was better than that of imported group, while the V40 and V50 in the imported group were better than those of domestic group, but only the V50 of the right femoral head had significant difference（t=-2.27, P=0.03）. The passing rate of the plan verification in the domestic group was significantly better than that of the imported group (t=9.89, P=0.00), and the number of MU decreased by 19.5% compared with that in the imported group. Conclusion Both the domestic and imported linear accelerators can get better target dose distribution in intensity modulated radiotherapy for prostate cancer. Although the volume of domestic accelerators in high dose irradiation of organs at risk is relatively high, they both meet the clinical dose requirements. Combined with the application of domestic equipment, it can be used in intensity modulated radiotherapy for prostate cancer in hospitals of different levels.