Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

Geum-mun Back; Sung Ho Park; Tae-Hyung Kim

doi:10.14316/pmp.2017.28.2.45

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Back, Park, and Kim: Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

Original Article

Progress in Medical Physics 2017;28(2):45-48.

Published online: 17 June 2017

DOI: https://doi.org/10.14316/pmp.2017.28.2.45

Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

Geum-mun Back, Sung Ho Park^†,, Tae-Hyung Kim^†

^∗Department of Radiation Oncology, Asan Medical Center, Seoul, Korea

^†Department of Neurosurgery, Ulsan University Hospital, Ulsan, Korea

^‡Department of Radiological Science, Kangwon National University, Samcheok, Korea

Corresponding author Sung Ho Park (michael@uuh.ulsan.kr) Tel: 82-52-250-7137 Fax: 82-52-250-7138

Received 17 March 20174 June 2017 Accepted 1 July 2017

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper evaluated the amount of radiation generated by wedge filters during radiation therapy using a high-energy linear accelerator, and the dose to the worker during wedge replacement. After 10-MV photon beam was irradiated with wedge filter, the wedge was removed from the linear accelerator, and the dose rate and energy spectrum were measured. The initial measurement was approximately 1 uSv/h, and the radiation level was reduced to 0.3 uSv/h after 6 min. The effective half-life derived from the dose rate measurement was approximately 3.5 min, and the influence of AI-28 was about 53%. From the energy spectrum measurements, a peak of 1,799 keV was measured for AI-28, while the peak for Co-58 was not measured in the control room. The peaks for Au-106 and Cd-105 were found only measurement was done without wedge removement from the linear accelerator. The additional doses received by the radiation worker during wedge replacement were estimated to be 0.08−0.4 mSv per year.

Keywords: Radiation dose, Wedge filter, Linear accelerator

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