Application of CARE Dose 4D in radiotherapy localization of nasopharyngeal carcinoma(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2021年第11期
- Page:
- 1349-1354
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Application of CARE Dose 4D in radiotherapy localization of nasopharyngeal carcinoma
- Author(s):
- CHENG Zhaojie; WEI Ting; LIANG Weixue; WANG Zhanyu; LIU Guangming; ZHOU Jianhong; LIN Huan
- Cancer Radiotherapy Center, Liuzhou Workers Hospital, Liuzhou 545005, China
- Keywords:
- Keywords: nasopharyngeal carcinoma CARE Dose 4D radiotherapy target area segmentation effective radiation dose
- PACS:
- R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2021.11.006
- Abstract:
- Abstract: Objective To investigate the application value of CARE Dose 4D technique in radiotherapy localization of nasopharyngeal carcinoma. Methods Sixty patients with nasopharyngeal carcinoma scheduled for radiotherapy were randomly divided into groups A and B, with 30 cases in each group. The patients in group A received routine CT examination with a tube voltage of 120 kV and a fixed value of 300 mAs, and those in group B were scanned with a tube voltage of 120 kV and CARE Dose 4D set at a preset value of 500 mAs. CIRS 064M electron density phantom was scanned by two different methods, thereby verifying if there was a difference in CT-RED conversion curve. The noise (SD), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), CT value at GTV, dose length product (DLP), volumetric CT dose index (CTDIvol) and effective radiation dose (ED) were objectively evaluated for 2 groups of images. The images were also scored subjectively by two senior physicians. Results There were no significant differences in CT values and CT-RED conversion curve between the two scanning methods, which guaranteed the accuracy of target area dose calculation. CTDIvol was 35% lower, and DLP and ED were both 43% lower in group B compared with group A, with statistically significant differences (P<0.001). The results of objective evaluation revealed that the differences in SNR, CNR and the mean CT values at GTV between two groups were trivial, without statistical differences (P>0.05), but the SD in the deltoid section in group A was higher than that in group B, with statistical differences (t=30.809, P<0.001). Moreover, there was significant difference in the subjective evaluation between two groups (z=-2.445, P<0.05). In the images of group A, the large noise in the cervical lymphatic drainage area within the shoulder cross-section caused some troubles for the physician to outline target areas on the section, thus the images in group B were superior to those in group A in terms of target area segmentation. Conclusion The application of CARE Dose 4D technique in radiotherapy localization of nasopharyngeal carcinoma is feasible, and it can improve image quality while significantly reducing the effective radiation dose to the patient.
Last Update: 2021-11-27