Polarity effect in commercial ionization chambers used in photon beams with small fields

Radiological Physics and Technology

Volumn 2, Issue 1, 2009, Pages 97-103

  Shimono, Tetsunori ^a   Koshida, Kichiro ^b   Nambu, Hidekazu ^c   Matsubara, Kosuke ^b   Takahashi, Hiroshi ^a   Okuda, Hiroshi ^a  

^a HOSHIGAOKA KOSEINENKIN HOSPITAL   (Japan)

^b KANAZAWA UNIVERSITY   (Japan)

^c KINDAI UNIVERSITY NARA HOSPITAL   (Japan)

Author keywords

Ionization chamber; Polarity effect; Small field

Indexed keywords

ARTICLE; DOSIMETRY; ELECTRODE; ENERGY; IONIZATION CHAMBER; PHOTON THERAPY; PRIORITY JOURNAL; RADIOGRAPHY;

CALIBRATION; ELECTRICITY; PHOTONS; RADIOMETRY;

EID: 64249129990     PISSN: 18650333     EISSN: None     Source Type: Journal    
DOI: 10.1007/s12194-008-0050-1     Document Type: Article

References (21)

1. P Andreo 2000 On the beam quality specification of high-energy photons for radiotherapy dosimetry Med Phys 27 434 44
2. P Francescon S Cora C Cavedon 1998 Use of a new type of radiochromic firm, a new parallel-plate micro-chambers, MOSFETs and TLD 800 microcubes in the dosimetry of small beams Med Phys 25 503 11
3. C Martens DC Watger DW Neve 2000 The value of the PinPoint ion chamber for characterization of small field segments use in intensity-modulated radiotherapy Phys Med Biol 45 2519 30
4. DA Low RL Gerber S Mutic JA Purdy 1998 Phantoms for IMRT dose distribution measurement and treatment verification Int J Radiat Oncol Biol Phys 40 1231 5
5. DA Low KS Chao S Mutic RL Gerber CA Perez JA Purdy 1998 Quality assurance of serial tomotherapy for head and neck patient treatment Int J Radiat Oncol Biol Phys 42 681 92
6. X Ezzel 2003 Guidance document on delivery, treatment planning, and clinical implementation of IMRT Report of the IMRT subcommittee of the AAPM radiation therapy committee Med Phys 30 2089 115
7. H Aget JC Rosenwald 1991 Polarity effect for various ionization chambers with multiple irradiation conditions in electron beam Med Phys 18 67 72
8. BJ Gerbi FM Khan 1987 The polarity effect for commercially available plane-parallel ionization chambers Med Phys 14 210 5
9. CS Reft F Kuchnir 1991 Measurement of the replacement correction factor for parallel-plate chambers in electron fields Med Phys 18 1237 43
10. LO Mattsson KA Johansson H Svensson 1981 Calibration and use of plane parallel ionization chambers for the determination of absorbed dose is electron beams Acta Radiol Oncol 20 385 99
11. JA Williams SK Agarwal 1997 Energy-dependent polarity correction factors for four commercial ionization chambers used in electron dosimetry Med Phys 24 785 90
12. G Wickman T Holmstrom 1992 Polarity effect in plane-parallel ionization chambers using air or a dielectric liquid as ionization medium Med Phys 19 637 40
13. H Kubo 1993 Evaluations of two solid water parallel-plate chambers in high-energy photon and electron beams Med Phys 20 341 5
14. BJ Gerbi 1993 The response characteristics of a newly designed plane-parallel ionization chamber in high-energy photon and electron beams Med Phys 20 1411 5
15. AAPM, American Association of Physicists in Medicine, Task Group No. 25, Radiation Therapy Committee. Clinical electron beam dosimetry: report of AAPM radiation therapy committee task group No. 25. Med Phys. 1991;18:73-109.
16. JP McCaffrey B Downton H Shen D Niven M McEwen 2005 Pre-irradiation effects on ionization chambers used in radiation therapy Phys Med Biol 50 121 33
17. JW Boag 1963 Distortion of the electric field in an ionization chamber due to a difference in potential between guard electrode and collector Phys Med Biol 9 25 32
18. D Novkovic Z Milosevic K Subotic S Manic-Kudra 1996 Numerical solutions of differential equations of a cylindrical ionization chamber Phys Med Biol 41 725 41
19. F Araki 2006 Monte Carlo study of a Cyberknife stereotactic radiosurgery system Med Phys 33 2955 63
20. SE Burch KJ Kearfott JH Trueblood WC Sheils JI Yeo CKC Wang 1997 A new approach to firm dosimetry for high energy photon beams: lateral scatter filtering Med Phys 24 775 83
21. JR Sykes HV James PC Williams 1999 Letter to the editor: how much does firm sensitivity increase at depth for larger field sizes? Med Phys 26 329 30