Analysis of dosimetric differences between active control and passive tracking of jaws
10.13491/j.issn.1004-714X.2023.05.015
- VernacularTitle:钨门主动控制与被动跟随的剂量学差异性分析
- Author:
Liyuan CAO
1
;
Yongjian JU
1
;
Kexin LI
1
Author Information
1. Department of Radiotherapy, Second Affiliated Hospital of Nantong University, Nantong 226001 China.
- Publication Type:OriginalArticles
- Keywords:
Fixed-jaw;
Dynamic intensity-modulated radiotherapy;
Dose distribution;
Dosimetric verification
- From:
Chinese Journal of Radiological Health
2023;32(5):556-559
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the effect of the fixed-jaw technique on dosimetric parameters during dynamic intensity-modulated radiotherapy (DIMRT) planning. Methods Ten patients each with nasopharyngeal carcinoma, postoperative cervical cancer, and right breast cancer after radical surgery were selected for this study; all patients underwent DIMRT in our hospital in 2020. After administration at the prescribed dose, two methods were used to design the radiotherapy plan for each patient: split-field technique (SFT) and fixed-jaw technique (FJT). The two plans were compared for the differences in the dosimetric parameters and plan verification pass rate. Results Compared with SFT, FJT showed significant decreases (P <0.05) in the following parameters for patients with nasopharyngeal carcinoma, postoperative cervical cancer, and right breast cancer after radical surgery: number of radiation fields (down by 41.5%, 47.3%, and 34.9%, respectively, t = 7.954, 24.2, and 4.949, respectively), total number of monitor units (MUs) (down by 5.6%, 5.3%, and 13.5%, respectively, t = 3.211, 2.423, and 5.481, respectively), and actual beam-on time (down by 25.3%, 23.8%, and 13.6%, respectively, t = 5.814, 9.208, and 5.655, respectively). There were significant differences in some of the dosimetric parameters for all three types of cancer patients between the two plans (P <0.05). There were no significant differences in the plan verification pass rate (P >0.05). Conclusion FJT can reduce the total number of MUs and actual beam-on time while meeting the requirements for clinically prescribed doses in DIMRT planning.
