3-Dimensional Dosimetry of Small Field Photon Beam.
- Author:
Jisun JANG
1
;
Soo Il KWON
Author Information
1. CyberKnife Center, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Small field dosimetry;
Gel dosimetry;
Radiosugery;
3D dose distribution
- MeSH:
Antineoplastic Combined Chemotherapy Protocols;
Cytarabine;
Head;
Magnetic Resonance Imaging;
Neck;
Polymers;
Quality Control;
Thioguanine
- From:Korean Journal of Medical Physics
2012;23(1):54-61
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
A polymer gel dosimeter was fabricated. A 3-dimensional dosimetry experiment was performed in the small field of the photon of the cyberknife. The dosimeter was installed in a head and neck phantom. It was manufactured from the acrylic and it was used in dosimetry. By using the head and neck CT protocol of the CyberKnife system, CT images of the head and neck phantom were obtained and delivered to the treatment planning system. The irradiation to the dosimeter in the treatment planning was performed, and then, the image was obtained by using 3.0T magnetic resonance imaging (MRI) after 24 hours. The dose distribution of the phantom was analyzed by using MATLAB. The results of this measurement were compared to the results of calculation in the treatment planning. In the isodose curve on the axial direction, the dose distribution coincided with the high dose area, 0.76mm difference on 80%, rather than the low dose area, 1.29 mm difference on 40%. In this research, the fact that the polymer gel dosimeter and MRI can be applied for analyzing a small field in a 3 dimensional dosimetry was confirmed. Moreover, the feasibility of using these for the therapeutic radiation quality control was also confirmed.
