Objective To investigate the application effect of spiral fault fixed field intensity modulated radiation therapy(IMRT) in middle segment esophageal carcinoma.Methods A total of 83 IMRT and TD patients received radiotherapy in our hospital for middle esophageal cancer were selected,and IMRT and TD radiotherapies were applied by Pinnacle 39.0 treatment planning system by cloth field and location shooting,The average dose,acceptable dosages of 5％ and 95％ organ volume,30 ～ 40 Gy dosage volume of heart,the maximum dose of spinal cord,the volumes of lungs with doses of 5,20 and 30 Gy,average dose of normal tissue,conformal index and evenness index were assessed.Results TD plan had superior target area conformal and evenness indicators,and acceptable dosages of 5 ％ organ volume as compared to IMRT (P ＜ 0.05).The comparison of organs at risk showed that IMRT plans had larger volumes of lungs with doses of 20 and 30Gy than TD plan (P ＜0.05),but no significant difference was seen in other indexes (P ＞ 0.05).Conclusion Compared with intensity modulated radiation therapy,helical tomographic fixed field intensity-modulated radiation therapy can better improve target area conformal and evenness indicators,and reduce maximum dose of both lungs.

Objective To investigate the application effect of spiral fault fixed field intensity modulated radiation therapy(IMRT) in middle segment esophageal carcinoma.Methods A total of 83 IMRT and TD patients received radiotherapy in our hospital for middle esophageal cancer were selected,and IMRT and TD radiotherapies were applied by Pinnacle 39.0 treatment planning system by cloth field and location shooting,The average dose,acceptable dosages of 5％ and 95％ organ volume,30 ～ 40 Gy dosage volume of heart,the maximum dose of spinal cord,the volumes of lungs with doses of 5,20 and 30 Gy,average dose of normal tissue,conformal index and evenness index were assessed.Results TD plan had superior target area conformal and evenness indicators,and acceptable dosages of 5 ％ organ volume as compared to IMRT (P ＜ 0.05).The comparison of organs at risk showed that IMRT plans had larger volumes of lungs with doses of 20 and 30Gy than TD plan (P ＜0.05),but no significant difference was seen in other indexes (P ＞ 0.05).Conclusion Compared with intensity modulated radiation therapy,helical tomographic fixed field intensity-modulated radiation therapy can better improve target area conformal and evenness indicators,and reduce maximum dose of both lungs.