Jacek Wendykier1, Aleksandra Grządziel1, Barbara Bekman1, Marcin Bieniasiewicz2, Adam Bekman3, Piotr Wendykier4, Bożena Woźniak3, Marta Reudelsdorf1, Krzysztof Ślosarek1. 1. Radiotherapy Planning Department, Maria Sklodowska-Curie Institute - Oncology Center Gliwice Branch, Gliwice, Poland. 2. Radiotherapy Center, Department of Medical Physics, Multidisciplinary Hospital, Gorzów Wielkopolski, Poland. 3. Medical Physics Department, Maria Sklodowska-Curie Institute - Oncology Center Gliwice Branch, Gliwice, Poland. 4. Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland.
Abstract
BACKGROUND: The comparison between profiles during the commissioning of the treatment planning system is an essential procedure. It is impossible to designate a field size for off-axis, wedged, and FFF beams directly by using the definition of the on-axis symmetric field size. This work proposes the use of different characteristic points as indicators of the field size for commissioning and QA purposes. This work aimed to search for the beam profile's characteristic points and use them for the TPS commissioning purposes. MATERIALS AND METHODS: The proposal is to use profile inflection points as the beam profile characteristic points. The usage of dedicated software allowed for comparing distances between inflection points and between points of 50% intensity. For the off-axis, wedged, and FFF fields, comparisons were made to the nominal field sizes. RESULTS: Distances between inflection points proved to be different by less than 1 mm from nominal field sizes for all kinds of investigated beams. CONCLUSIONS: Inflection points are convenient for comparing the off-axis, wedged, and FFF field sizes because of their independence from profile normalization. With finite accuracy, the inflection points could be used for the above kind of beam sizes designation.
BACKGROUND: The comparison between profiles during the commissioning of the treatment planning system is an essential procedure. It is impossible to designate a field size for off-axis, wedged, and FFF beams directly by using the definition of the on-axis symmetric field size. This work proposes the use of different characteristic points as indicators of the field size for commissioning and QA purposes. This work aimed to search for the beam profile's characteristic points and use them for the TPS commissioning purposes. MATERIALS AND METHODS: The proposal is to use profile inflection points as the beam profile characteristic points. The usage of dedicated software allowed for comparing distances between inflection points and between points of 50% intensity. For the off-axis, wedged, and FFF fields, comparisons were made to the nominal field sizes. RESULTS: Distances between inflection points proved to be different by less than 1 mm from nominal field sizes for all kinds of investigated beams. CONCLUSIONS: Inflection points are convenient for comparing the off-axis, wedged, and FFF field sizes because of their independence from profile normalization. With finite accuracy, the inflection points could be used for the above kind of beam sizes designation.
Authors: J L Bedford; P J Childs; V Nordmark Hansen; M A Mosleh-Shirazi; F Verhaegen; A P Warrington Journal: Br J Radiol Date: 2003-03 Impact factor: 3.039
Authors: Eduard Gershkevitsh; Csilla Pesznyak; Borislava Petrovic; Joseph Grezdo; Krzysztof Chelminski; Maria do Carmo Lopes; Joanna Izewska; Jacob Van Dyk Journal: Acta Oncol Date: 2013-10-28 Impact factor: 4.089
Authors: M C Lopes; A Cavaco; K Jacob; L Madureira; S Germano; S Faustino; J Lencart; M Trindade; J Vale; V Batel; M Sousa; A Bernardo; S Brás; S Macedo; D Pimparel; F Ponte; E Diaz; A Martins; A Pinheiro; F Marques; C Batista; L Silva; M Rodrigues; L Carita; E Gershkevitsh; J Izewska Journal: Phys Med Date: 2013-04-23 Impact factor: 2.685