|Table of Contents|

Analysis of the influence of the level difference between accelerator and positioning CT bed board on the dosimetry of radiotherapy plan for nasopharyngeal carcinoma

Journal Of Modern Oncology[ISSN:1672-4992/CN:61-1415/R]

Issue:
2023 11
Page:
2080-2085
Research Field:
Publishing date:

Info

Title:
Analysis of the influence of the level difference between accelerator and positioning CT bed board on the dosimetry of radiotherapy plan for nasopharyngeal carcinoma
Author(s):
LIU Xiaolong1; ZHANG Jing1; LI Lei1; HAN Yunwei1; LUO Yamei2; YANG Bo1; 2
1.Department of Oncology，the Affiliated Hospital of Southwest Medical University，Sichuan Luzhou 646000,China;2.Medicine & Engineering & Informatics Fusion and Transformation Key Laboratory of Luzhou City，Sichuan Luzhou 646000，China.
Keywords:
CT couch; tilt; iso-center; setup; nasopharyngeal carcinoma
PACS:
R739.6
DOI:
10.3969/j.issn.1672-4992.2023.11.020
Abstract:
Objective:To analyze the change of radiotherapy center position and dose distribution due to the horizontal difference between the accelerator bed and the positioning CT bed.Methods:Twenty radiotherapy plans of patients with nasopharyngeal carcinoma were selected.It was assumed that the positioning CT bed plate were inclined at 1° and 2° respectively，the distance difference of radiotherapy center were calculated by making geometric figures.Results:The distance difference of radiotherapy center were 1.45 mm for 1°，and 2.89 mm for 2°.With the increase of the tilt angle，the HI and CI of PTV2 became worse，the D95% of target areas became gradually smaller and the dose of the spinal cord and brain stem increased（P＜0.05）.Conclusion:The tilting of the positioning CT bed plate has an effect on the radiotherapy center positionand dose distribution,the level of the positioning CT bed and accelerator bed should be consistent.It is suggested to establish an evaluation method of dose difference caused by the horizontal difference of bed.

References:

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Memo

Memo:
四川省科技计划项目（编号：2020JDTD0036）;医工医信融合与转化医学泸州市重点实验室项目（编号：XGY202105）;四川省医学科研课题（编号：S19007）
Last Update: 2023-04-28