千伏级锥形束kV-CBCT在鼻咽癌调强放疗摆位误差的研究  

Kilovoltage Cone-Beam CT in the Evaluation of Set-Up Errors in the Nasopharyngeal Carcinoma with Intensity Modulated Radiotherapy

作　　者：莫小眯 肖爱农[2] 伍海彪[2] 屈国普[1] 谭甄干 

机构地区：[1]南华大学核科学技术学院,湖南衡阳421001 [2]南华大学附属第一医院放射治疗科

出　　处：《中国辐射卫生》2016年第2期206-208,共3页Chinese Journal of Radiological Health

基　　金：2015湖南省重点研发计划(2015SK2022)

摘　　要：目的应用机载千伏级锥形束CT(CBCT)分析鼻咽癌调强放射治疗的摆位误差。方法本研究选取32例IMRT的鼻咽癌患者,治疗过程中每周一次治疗前行CBCT扫描,获取的CBCT图像和CT图像匹配后得出三维方向上的平移误差。结果摆位误差绝对值分别为左右(1.50±0.87)mm,头脚(1.59±0.87)mm,腹背(1.95±0.99)mm,根据van Herk公式计算得到各个方向的PTV外扩值分别为左右2.9 mm、头脚4.5 mm、腹背3.1 mm。结论建议PTV不均匀外扩;腹背方向摆位误差较左右、头脚方向大,在摆位中应注意误差大的方向,提高摆位的准确性。Objective To analyze the setup errors using Kilovohage X - ray cone - beam CT imaging in nasopharyngeal carcinoma treated by intensity modulated radiotherapy. Methods 32 patients diagnosed with nasopharyngeal carcinoma and treated with IMRT were selected. Kilovoltage cone - beam scan was performed weekly before treatment. The setup errors on trans-lational directions （X, Y, Z） were obtained by matching the CBCT images and the planning CT images. Results The average errors were （ 1.50 ± 0.87 ） mm, （ 1.59 ± 0.87 ） mm and （ 1.95 ± 0.99 ） mm for right - left, head - feet and anteriority - posterior direction respectively. According to the Van Herk formula, PTV margins were 2.9 mm, 4.5 mm and 3.1 mm, respectively. Conlusion The results showed that the setup errors in anteriority - posterior direction were larger than in right - left and head -feet direction, which should be taken care during the patient daily setup.

关 键 词：鼻咽癌 摆位误差 锥形束CT 调强放射治疗 

分 类 号：R144[医药卫生—公共卫生与预防医学]