Dose Analysis of a Diode Array for Dose Verification of Rotational Intensity Modulated Radiation Therapy Planning
- VernacularTitle:二维半导体阵列实施旋转调强治疗计划验证的剂量学评估
- Author:
Shouping XU
;
Chuanbin XIE
;
Xiangkun DAI
;
Zhongjian JU
;
Hanshun GONG
;
Ruigang GE
- Publication Type:Journal Article
- Keywords:
2D diode array;
rotational IMRT;
dose verification;
gamma analysis
- From:
Chinese Journal of Medical Physics
2009;26(6):1477-1480,1494
- CountryChina
- Language:Chinese
-
Abstract:
Objective: Quality assurance (QA) of intensity modulated radiotherapy (IMRT) dosimetry is a laborious task. The goal of this work is to evaluate the dosimetric characteristics of a new 2D diode array and assess the role it can play in routine MRT QA. Methods: A diode array, MapCHECK~(TM) and MapPHAN phantom from Sun Nuclear corporation (USC) were used for verifying the dose distribution of 10 tomotherapy IMRT plan cases. The combined phantom was set up to measure the dose distribution from coronal and sagittal orientations. After MVCT registration, the measured dose distributions of the coronal and sagittal planes were compared with those from calculation in the planning system. The results were evaluated by the absolute doses. The feasibility of the different measuring methods were studied. Results: The dose distribution measured by the MapCHECK~(TM) 2D array was well consistent with that calculated by tomotherapy planning system. In the comparison of the MapCHECK~(TM) measured versus planning system calculated using the 3mm/3% and 4mm/4% γ criteria, the number of detectors with γ parameter ≤ 1 was 96.8%/99.38% and 96.99%/99.49% average of the 10 cases respectively, for coronal and sagittal orientations. The acceptance criteria which is the combined 3mm/3% analysis would be introduced. And the number of points required to pass was generally 90%. Conclusions: MapCHECK~(TM) with MapPHAN phantom has been successfully tested for HT dose verification, and offers users an accurate and convenient rotational dosimetry solution.
