Measurement of output factors for small photon beams

Medical Physics - Tập 34 Số 6Part1 - Trang 1983-1988 - 2007
Otto A. Sauer1, Jürgen Wilbert1
1Klinik für Strahlentherapie, Klinikum der Julius-Maximilians-Universität, 97080 Würzburg, Germany

Tóm tắt

A variety of detectors and procedures for the measurement of small field output factors are discussed in the current literature. Different detectors with or without corrections are recommended. Correction factors are often derived by Monte Carlo methods, where the bias due to approximations in the model is difficult to judge. Over that, results appear to be contradictory in some cases. In this work, output factors were measured for field sizes from up to side length with different detectors. A simple linear correction for the energy response of solid state detectors is proposed. This led to identical values down to field size, as long as the size of the detector is small against the field size. The correction was of the order of a few percent. For a shielded silicon diode it was well below 1%. A physically meaningful function is proposed in order to calculate output factors for arbitrary field sizes with high accuracy.

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10.1118/1.1925187

10.1118/1.1758351

10.1088/0031-9155/49/16/015

10.1118/1.1544678

10.1118/1.1916048

10.1016/j.apradiso.2004.08.036

10.1118/1.1501138

10.1118/1.1536290

10.1088/0031-9155/48/14/304

10.1088/0031-9155/48/21/L01

10.1118/1.1446101

10.1088/0031-9155/41/1/008

10.1118/1.1514576

10.1118/1.1350437

10.1118/1.598793

10.1088/0031-9155/45/9/306

10.1088/0031-9155/44/9/303

10.1088/0031-9155/43/10/006

10.1118/1.598227

10.1259/0007-1285-39-466-727

Day M. J., 1996, Central axis depth dose data for use in radiotherapy: 1996, Br. J. Radiol., Suppl., 25, 138

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Medical Physics

Tập 34 Số 6Part1

1983-1988

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