An analysis of calibration coefficients measured in water and in air for Farmer-type cylindrical ionization chambers

• Autorzy: Wojciech Bulski , Piotr Ulkowski , Barbara Gwiazdowska , Joanna Rostkowska
• Języki publikacji: EN

Abstrakty

EN

A comparison of calibration coefficients of Farmer-type cylindrical ionization chambers calibrated in a Co-60 beam according to the IAEA Reports 277 and 398 formalisms.91 calibration coefficients measured in air and in water.The 398ND, W/277ND, W ratios were calculated, taking into account the wall material of the chambers. The correlation between 398ND, W and NK, ND, air277ND, W was made and the equations of the regression straight lines were determined.Calibration coefficients, determined according to the IAEA Report 398, are higher by about 1% than those determined according to the IAEA Report 277, and they depend slightly on the wall material of the chamber.The introduction of the IAEA dosimetry Report 398 resulted in an increase in the doses delivered to patients by about 1% as compared with the period of application of Report 277. The regression equations may assure increased accuracy in retrospective comparative calculation of doses according to both reports as compared with the correction based on mean percent values.

Słowa kluczowe

EN

calibration; dosimeters; ionization chambers; radiotherapy; SSDL

• Czasopismo: Polish Journal of Medical Physics And Engineering
• Rocznik: 2008
• Tom: 14
• Numer: 2
• Strony: 113-121

Daty

wydano

2008-01-01

online

2009-04-14

Twórcy

autor

Wojciech Bulski

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

autor

Piotr Ulkowski

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

autor

Barbara Gwiazdowska

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

autor

Joanna Rostkowska

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

Bibliografia

• Izewska J, Gajewski R. [Comparison of two ionometric methods of absorbed dose determination for high energy photon and electron beams]. Postepy Fizyki Medycznej. 1988; 24 (4): 223-242. Polish.
• IAEA. Absorbed dose determination in photon and electron beams. An international code of practice. Technical Reports Series, 2nd Edition, Vienna, 1997; No. TRS 277.
• Nordic Association of Clinical Physics. Procedures on external radiation therapy between 1 and 50 MeV. Acta Radiol Oncol. 1980; 19: 55.
• Nordic Association of Clinical Physics. Electron beams with mean energies at the phantom surface below 15 MeV. Supplement to the Recommendation by the NACP 1980. Acta Radiol Oncol. 1981; 20: 400.
• American Association of Physicists in Medicine. A protocol for the determination of absorbed dose from high energy photon and electron beams. Med Phys. 1983; 10: 741.
• IAEA. Absorbed Dose Determination in External Beam Radiotherapy. An International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water. Technical Reports Series. Vienna, 2000; No. TRS 398.
• Bjerke H, Hult EA. Dosimetric Criteria. Proceedings of the International Symposium on Practical Implementation of Clinical Audit for Medical Exposure. Tampere, Finland, 2004; 74-77.
• Huq MS, Andreo P. Advances in the determination of absorbed dose to water in clinical high-energy photon and electron beams using ionisation chambers. Phys Med Biol. 2004; 49: 49-104.

Identyfikatory

DOI

10.2478/v10013-008-0010-4