鼻咽癌IMRT海马头部、体部及尾部剂量分析

目的 探讨鼻咽癌患者IMRT计划中海马头部、体部及尾部的受量。方法 选取10例接受IMRT的鼻咽癌患者,在MRI T1加权相勾画左、右侧海马的头部、体部及尾部,提取照射剂量指标做比较。对海马头部、体部及尾部受量及受照体积比较行单因素方差分析,两两比较采用LSD法。WAIS-CR言语测试结果采用配对样本t检验。结果 左、右侧海马的平均受量分别为(1147±976)、(1011±602) cGy。左侧海马头部、体部及尾部的平均受量分别为(1739±1317)、(890±982)、(547±688) cGy (P=0.042);右侧海马头部、体部及尾部的平均受量分别为(1691±942)、(744±483)、(531±603) cGy (P=0.002)。海马头部、体部及尾部受量依次减少,不同照射剂量受照体积也依次减少。结论 鼻咽癌患者IMRT中海马头部、体部及尾部受量不同,海马头部受照量最高,值得临床关注。

Preliminary results of the exposed dose of head,body and tail of the hippocampus in nasopharyngeal carcinoma patients treated with intensity modulated radiotherapy

Objective To analyze the radiation doses to the head, body, and tail of the hippocampus in intensity-modulated radiotherapy(IMRT)for nasopharyngeal carcinoma(NPC). Methods Ten NPC patients treated with IMRT were selected,and the head, body, and tail of both hippocampi were delineated on T1-weighted images. The doses to the hippocampus were then analyzed. WAIS-CR speech test results were tested by paired sample t-test. Results The mean doses to left and right hippocampi were 1 147±976 cGy and 1 011±602 cGy, respectively. The mean doses to the head, body, and tail of the left hippocampus were 1 739± 1 317 cGy, 890± 982 cGy, and 547± 688 cGy, respectively(P=0.042);the mean doses to the head,body,and tail of the right hippocampus were 1 691±942 cGy,744±483 cGy,and 531±603 cGy,respectively(P=0.002).The dose to the hippocampus decreased from the head to the tail, and the irradiated volume also decreased as the dose varied. Conclusions The dose to hippocampus decreases from the head to the tail in NPC patients treated with IMRT,which is worthy of attention.