Display options
Share it on

Rep Pract Oncol Radiother. 2013 Jul 02;19(1):12-8. doi: 10.1016/j.rpor.2013.05.007. eCollection 2014 Jan.

Wax boluses and accuracy of EBT and RTQA radiochromic film detectors in radiotherapy with the JINR Phasotron proton beam.

Reports of practical oncology and radiotherapy : journal of Greatpoland Cancer Center in Poznan and Polish Society of Radiation Oncology

Dorota Maria Borowicz, Julian Malicki, Gennady Mytsin, Konstantin Shipulin

Affiliations

  1. Department of Medical Physics, Greater Poland Cancer Centre, 15 Garbary Street, 61-688 Poznan, Poland ; Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, 6 Joliot-Curie Street, 141980 Dubna, Moscow Region, Russia.
  2. Department of Medical Physics, Greater Poland Cancer Centre, 15 Garbary Street, 61-688 Poznan, Poland ; Electroradiology Department, University of Medical Sciences, 15 Garbary Street, 61-688 Poznan, Poland.
  3. Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, 6 Joliot-Curie Street, 141980 Dubna, Moscow Region, Russia.

PMID: 24936315 PMCID: PMC4054891 DOI: 10.1016/j.rpor.2013.05.007

Abstract

AIM: To present the results obtained using radiochromic films EBT and RTQA 1010P for the reconstruction the dose distributions for targets irradiated by proton beam and modified by wax boluses.

BACKGROUND: In Medico-Technical Complex at the Joint Institute for Nuclear Research in Dubna implemented technology of wax boluses.

MATERIALS AND METHODS: Wax boluses are easier to make and they give better dose distributions than boluses made from modeling clay previously used at our center. We irradiated two imaginary targets, one shaped as a cylinder and the other one as two cuboids. The evaluated calibration curve was used for calculation of the dose distributions measured by the EBT and RTQA radiochromic film. In both cases, the measured dose distributions were compared to the dose distributions calculated by the treatment planning system (TPS). We also compared dose distributions using three different conformity indices at a 95% isodose.

RESULTS: Better target coverage and better compliance of measurements (semiconductor detectors and radiochromic films) with calculated doses was obtained for cylindrical target than for cuboidal target. The 95% isodose covered well the tumor for both target shapes, while for cuboidal target larger volume around the target received therapeutic dose, due to the complicated target shape. The use wax boluses provided to be effective tool in modifying proton beam to achieve appropriate shape of isodose distribution.

CONCLUSION: EBT film yielded the best visual matching. Both EBT and RTQA films confirmed good conformity between calculated and measured doses, thus confirming that wax boluses used to modify the proton beam resulted in good dose distributions.

Keywords: Dosimetry; Proton therapy; Radiochromic films

References

  1. Expert Rev Neurother. 2010 Feb;10(2):319-30 - PubMed
  2. Med Dosim. 2006 Winter;31(4):273-82 - PubMed
  3. Phys Med. 2011 Jul;27(3):122-34 - PubMed
  4. Phys Med Biol. 1997 Oct;42(10):1887-98 - PubMed
  5. Phys Med Biol. 2005 Oct 21;50(20):N281-5 - PubMed
  6. Br J Cancer. 2005 Oct 17;93(8):849-54 - PubMed
  7. Rep Pract Oncol Radiother. 2011 Apr 08;16(3):95-102 - PubMed
  8. Rep Pract Oncol Radiother. 2012 Jun 03;17(4):190-9 - PubMed
  9. J Radiat Res. 2012;53(2):272-80 - PubMed
  10. Australas Phys Eng Sci Med. 2008 Sep;31(3):203-6 - PubMed
  11. J Appl Clin Med Phys. 2007 Oct 24;8(4):65-75 - PubMed
  12. Rep Pract Oncol Radiother. 2012 Mar 06;17(2):63-5 - PubMed
  13. Rep Pract Oncol Radiother. 2012 Feb 09;17(2):104-9 - PubMed
  14. Phys Med. 2005 January - March;21(1):15-21 - PubMed
  15. Phys Med Biol. 2004 Feb 21;49(4):R49-104 - PubMed
  16. Radiol Oncol. 2011 Dec;45(4):310-4 - PubMed
  17. Phys Med. 2009 Sep;25(3):105-10 - PubMed
  18. Radiol Oncol. 2011 Mar;45(1):1-16 - PubMed
  19. Rep Pract Oncol Radiother. 2010 Mar 30;15(2):40-6 - PubMed
  20. Phys Med Biol. 2010 Aug 21;55(16):4771-82 - PubMed

Publication Types