You need JavaScript to view this

A beam-matching concept for medical linear accelerators

Abstract

The flexibility in radiotherapy can be improved if a patient can be moved between any one of the Department's medical linear accelerators without the need to change anything in the patient's treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must be the same, or nearly the same i.e. the accelerators must be beam-matched. During a period of nine months, eight Varian iX accelerators with 6 and 15 MV photon beams and 6-18 MeV electron beams (only four of the eight) were installed at our clinic. All accelerators fulfilled the vendor-defined 'fine beam-match' criteria, and a more extensive set of measurements was carried out during commissioning. The measured absorbed dose data for each accelerator were compared with the first accelerator, chosen as reference, and the TPS calculations. Two of the eight accelerators showed a larger discrepancy for the 15 MV beam not revealed by the vendor-defined acceptance criteria, whereas the other six accelerators were satisfactorily matched. The beam-matching acceptance criteria defined by the vendor are not strict enough to guarantee optimal beam-match. Deviations related to dose calculations and to beam-matched accelerators may add up. The safest and most practical way to ensure that all accelerators  More>>
Authors:
Sjoestroem, David; Bjelkengren, Ulf; Ottosson, Wiviann; Behrens, Claus F [1] 
  1. Dept. of Oncology, Div. of Radiophysics, Copenhagen Univ. Hospital, Herlev (Denmark)
Publication Date:
Feb 15, 2009
Product Type:
Journal Article
Resource Relation:
Journal Name: Acta Oncologica (Stockholm) (online); Journal Volume: 48; Journal Issue: 2; Other Information: 16 refs.
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; RADIATION DOSES; LINEAR ACCELERATORS; INTERCHANGEABILITY
OSTI ID:
947677
Country of Origin:
Sweden
Language:
English
Other Identifying Numbers:
Journal ID: ISSN 1651-226X; TRN: SE0908043
Availability:
Available from DOI: http://dx.doi.org//10.1080/02841860802258794
Submitting Site:
SWDN
Size:
page(s) 192-200
Announcement Date:
Feb 23, 2009

Citation Formats

Sjoestroem, David, Bjelkengren, Ulf, Ottosson, Wiviann, and Behrens, Claus F. A beam-matching concept for medical linear accelerators. Sweden: N. p., 2009. Web.
Sjoestroem, David, Bjelkengren, Ulf, Ottosson, Wiviann, & Behrens, Claus F. A beam-matching concept for medical linear accelerators. Sweden.
Sjoestroem, David, Bjelkengren, Ulf, Ottosson, Wiviann, and Behrens, Claus F. 2009. "A beam-matching concept for medical linear accelerators." Sweden.
@misc{etde_947677,
title = {A beam-matching concept for medical linear accelerators}
author = {Sjoestroem, David, Bjelkengren, Ulf, Ottosson, Wiviann, and Behrens, Claus F}
abstractNote = {The flexibility in radiotherapy can be improved if a patient can be moved between any one of the Department's medical linear accelerators without the need to change anything in the patient's treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must be the same, or nearly the same i.e. the accelerators must be beam-matched. During a period of nine months, eight Varian iX accelerators with 6 and 15 MV photon beams and 6-18 MeV electron beams (only four of the eight) were installed at our clinic. All accelerators fulfilled the vendor-defined 'fine beam-match' criteria, and a more extensive set of measurements was carried out during commissioning. The measured absorbed dose data for each accelerator were compared with the first accelerator, chosen as reference, and the TPS calculations. Two of the eight accelerators showed a larger discrepancy for the 15 MV beam not revealed by the vendor-defined acceptance criteria, whereas the other six accelerators were satisfactorily matched. The beam-matching acceptance criteria defined by the vendor are not strict enough to guarantee optimal beam-match. Deviations related to dose calculations and to beam-matched accelerators may add up. The safest and most practical way to ensure that all accelerators are within clinical acceptable accuracy is to include TPS calculations in the evaluation. Further, comparisons between measurements and calculations should be done in absolute dose terms}
journal = []
issue = {2}
volume = {48}
place = {Sweden}
year = {2009}
month = {Feb}
}