目的 针对胸中段食管癌患者,定量评估图像引导频率对摆位误差的影响,寻求临床靶区体积到计划靶区体积(CTV-PTV)的最佳外扩值.方法 选择安阳市肿瘤医院2018-06-01-2020-01-01接受螺旋断层放疗的胸中段食管癌患者62例,每次治疗前行兆伏级CT(MVCT)扫描,获得摆位误差.分析不同图像引导频率(0％、4％、11％、19％、23％、37％和50％)对于摆位误差的影响.17例患者治疗后再次行MVCT扫描得出分次内摆位误差,结合胸中段食管运动幅度的前期研究,得出最佳CTV-PTV外扩值.结果 随着图像引导频率增加,系统误差在X(左右)、Y(头脚)、Z(腹背)3个方向逐渐减小,随机误差增减趋势不明显.即使图像引导频率达到50％,在X、Y、Z方向仍分别有1.3％、6.6％和0.2％的摆位误差>10 mm.根据17例胸中段食管癌患者分次内摆位误差,得出X、Y、Z 3个方向CTV-PTV的外扩值分别为1.48、2.48和1.80 mm.结论 随着图像引导频率的增加,摆位误差呈减少趋势,但是仍然存在一定比例误差较大的情况,建议胸中段食管癌患者每次治疗前行MVCT图像引导.此外,放疗过程中由于患者不自主运动以及食管本身运动带来的影响,仍然需要一定的CTV-PTV外扩以保证肿瘤靶区得到足够的辐射剂量.

Objective To analyze setup errors and guide the calculation of margins from clinical target volume (CTV) and planning target volume (PTV) in esophageal cancer patients treated with tomothcrapy by the MVCT image-guided system.Methods Sixty-four esophageal canccr patients trcated with tomotherapy in our hospital in 2016 were randomly selected.MVCT images were acquired after patients' positioning and co-registered with KVCT images.The setup errors of x,y,and z translations and roll rotation were analyzed with the t-test or one-way ANOVA.Meanwhile,PTV margin was calculated based on the formula of M =2.5 Σ + 0.7δ Results According to the formula,the CTV-PTV margins in the x,y and z directions are slightly different between cancers located in the cervical,upper thoracic,middle thoracic,and lower thoracic segments.In patients with upper thoracic esophageal cancer,the average setnp error in the yaxis was lower when the head-neck-shoulder thermoplastic film fixation was used than when somatic thermoplastic film fixation (P=0.000);the setup errors of z-axis with somatic thermoplastic film fixation in the fifth and sixth weeks were slightly less than those in the first several weeks (P =0.036);the setup errors acquired by three image registration patterns were similar (x-axis P=0.868,y-axis P=0.491,z-axis P=0.169,roll P=0.985).Conclusions In the treatment of patients with esophageal cancer,the setup errors are large,but the MVCT in the TOMO HD system can greatly reduce the setup errors,ensuring the accuracy of each treatment.It is further recommended that in clinical practice,different CTV-PTV margins should be used for the treatments of esophageal cancers located in different segments.Patients with upper thoracic esophageal cancer are advised to use the head-neck-shoulder thermoplastic film fixation.

目的：研究探讨 Tomo 治疗系统在宫颈癌治疗中的应用效果。方法：选择自2015年11月至2016年2月我院收治的82例宫颈癌患者作为研究对象，按照数字随机法将其分为对照组和观察组两组，每组41例。其中对照组患者采取常规放射治疗，观察组患者则采用 Tomo 治疗系统进行治疗，比较两组患者的治疗效果。结果：观察组患者近期疗效的有效率为92．68％，显著高于对照组的75．61％，差异具有统计学意义（P ＜0．05）。观察组患者放射性直肠炎和膀胱炎的发生率显著低于对照组（P ＜0．05），两组患者恶心、干呕以及发热等不良反应的发生率差异无统计学意义（P ＞0．05）。结论：Tomo 治疗系统在宫颈癌患者治疗过程中效果良好，可显著降低常规放射治疗不良反应的发生率，安全性较好，且实用性强，值得临床推荐。

为探讨异常胰胆管连接（ＡＰＢＤＵ）在胰胆系病变病因学中的作用及其发病机制，分析比较了７９例ＡＰＢＤＵ和５９例正常胰胆管连接患者的临床和经内镜逆行胰胆管造影结果；并用２６只犬分三组建立动物模型，于术后第５～１２０天检测血清淀粉酶、磷脂酶Ａ２活性和甘胆酸含量，第９０～２７０天作胰胆管造影和病理学检查。结果：胆管炎、胆管囊肿、胆系癌和慢性胰腺炎在ＡＰＢＤＵ组的发生率显著增高。实验研究也在多数犬复制出上述病变。结果提示ＡＰＢＤＵ对多种胰胆系病变有明确的致病作用，其致病机制是胆汁与胰液混流后，激活胰酶，从而引起胰胆管上皮损害。建议对于反复并发胰胆系病变的ＡＰＢＤＵ患者，在治疗胰胆系疾病的同时宜考虑实施胰胆管重建手术