Evaluation of uncertainty predictions and dose output for model-based dose calculations for megavoltage photon beams

Medical Physics

Volumn 33, Issue 7, 2006, Pages 2548-2556

  Olofsson, Jörgen ^a   Nyholm, Tufve ^a   Georg, Dietmar ^b   Ahnesjö, Anders ^a,c,d   Karlsson, Mikael ^a  

^a UMEÅ UNIVERSITY   (Sweden)

^b UNIVERSITY OF VIENNA   (Austria)

^c Elekta AB   (Sweden)

^d UPPSALA UNIVERSITY   (Sweden)

Author keywords

MLC; MU verification; Output factors; Pencil kernel; Uncertainties

Indexed keywords

BIOMEDICAL ENGINEERING; ERRORS; FORECASTING; PARTICLE BEAMS; PHOTOELECTRONS; PHOTONS;

ERROR DISTRIBUTIONS; MEGAVOLTAGE PHOTONS; MODEL BASED APPROACH; MULTILEAF COLLIMATORS; OUTPUT FACTORS; PENCIL KERNEL; TREATMENT TECHNIQUES; UNCERTAINTIES;

UNCERTAINTY ANALYSIS;

ARTICLE; COLLIMATOR; DOSE CALCULATION; ENERGY; MEASUREMENT; MEGAVOLTAGE RADIATION; PHOTON; PREDICTION; PRIORITY JOURNAL; RADIATION DOSE; RADIATION MONITOR; RADIOTHERAPY; RELIABILITY; UNCERTAINTY;

EID: 33745661430     PISSN: 00942405     EISSN: None     Source Type: Journal    
DOI: 10.1118/1.2207316     Document Type: Article

References (24)

1. A. Dutreix, H. Svensson, B. E. Bjärngard, A. Bridier, B. Mijnheer, and J. Shaw, " Monitor unit calculation for high energy photon beams., " Physics for Clinical Radiotherapy, Booklet No. 3, ESTRO (Garant, Leuven, Belgium, 1997).
2. J. J. van Gasteren, S. Heukelom, H. N. Jager, B. J. Mijnheer, R. van der Laarse, H. J. van Kleffens, J. L. Venselaar, and C. F. Westermann, " Determination and use of scatter correction factors of megavoltage photon beams., " Netherlands Commission on Radiation Dosimetry, NCS Report No. 12 (NCS, Delft, The Netherlands, 1998).
3. N. Linthout, D. Verellen, S. Van Acker, and G. Storme, " A simple theoretical verification of monitor unit calculation for intensity modulated beams using dynamic mini-multileaf collimation., " Radiother. Oncol. 71, 235-241 (2004).
4. T. Knöös, S. A. Johnsson, C. P. Ceberg, A. Tomaszewicz, and P. Nilsson, " Independent checking of the delivered dose for high-energy x-rays using a hand-held PC., " Radiother. Oncol. 58, 201-208 (2001).
5. A. Ahnesjö, T. Knöös, and A. Montelius, " Application of the convolution method for calculation of output factors for therapy photon beams., " Med. Phys. 19, 295-301 (1992).
6. P. Storchi and E. Woudstra, " Calculation of the absorbed dose distribution due to irregularly shaped photon beams using pencil beam kernels derived from basic beam data., " Phys. Med. Biol. 41, 637-656 (1996).
7. H. Hansson, P. Björk, T. Knöös, and P. Nilsson, " Verification of a pencil beam based treatment planning system: output factors for open photon beams shaped with MLC or blocks., " Phys. Med. Biol. 44, N201-N207 (1999).
8. D. Georg and A. Dutreix, " A formalism to calculate the output ratios in a mini-phantom for a GE multileaf collimator., " Phys. Med. Biol. 42, 521-536 (1997).
9. A. R. Hounsell and J. M. Wilkinson, " Head scatter modeling for irregular field shaping and beam intensity modulation., " Phys. Med. Biol. 42, 1737-1749 (1997).
10. S. Kim, J. R. Palta, and T. C. Zhu, " A generalized solution for the calculation of in-air output factors in irregular fields., " Med. Phys. 25, 1692-1701 (1998).
11. S. B. Jiang, A. L. Boyer, and C. M. Ma, " Modelling the extrafocal radiation and monitor chamber backscatter for photon beam dose calculation., " Med. Phys. 28, 55-66 (2001).
12. D. Georg, J. Olofsson, T. Kunzler, and M. Karlsson, " On empirical methods to determine scatter factors for irregular MLC shaped beams., " Med. Phys. 31, 2222-2229 (2004).
13. J. Olofsson, D. Georg, and M. Karlsson, " A widely tested model for head scatter influence on photon beam output., " Radiother. Oncol. 67, 225-238 (2003).
14. N. Dunscombe and J. M. Nieminen, " On the field size dependence of relative output factors from a linear accelerator., " Med. Phys. 19, 1441-1444 (1992).
15. A. Ahnesjö, " Analytic modeling of photon scatter from flattening filters in photon therapy beams., " Med. Phys. 21, 1227-1235 (1994).
16. T. Nyholm, J. Olofsson, A. Ahnesjö, and M. Karlsson, " Photon pencil kernel parameterization based on beam quality index., " Radiother. Oncol. 78, 347-351 (2006).
17. A. Ahnesjö, M. Saxner, and A. Trepp, " A pencil beam model for photon dose calculation., " Med. Phys. 19, 263-273 (1992).
18. T. Nyholm, J. Olofsson, A. Ahnesjö, and M. Karlsson, " Modelling lateral beam quality variations in pencil kernel based photon dose calculations. " (to be published).
19. R. C. Tailor, V. M. Tello, and C. B. Schroy, " A generic off-axis energy correction for linac photon beam dosimetry., " Med. Phys. 25, 662-667 (1998).
20. T. Nyholm, J. Olofsson, A. Ahnesjö, and M. Karlsson, " Pencil kernel correction and residual error estimation for quality index based photon dose calculations. " (unpublished).
21. J. Yang, J. S. Li, L. Qin, W. Xiong, and C. M. Ma, " Modelling of electron contamination in clinical photon beams for Monte Carlo dose calculation., " Phys. Med. Biol. 49, 2657-2673 (2004).
22. L. Weber, P. Nilsson, and A. Ahnesjö, " Build-up cap materials for measurement of photon head scatter factors., " Phys. Med. Biol. 42, 1875-1886 (1997).
23. Y. Zhu, A. L. Boyer, and G. E. Desobry, " Dose distributions of x-ray fields shaped with multileaf collimators., " Phys. Med. Biol. 37, 163-173 (1992).
24. S. A. Naqvi, M. Sarfaraz, T. Holmes, C. X. Yu, and X. A. Li, " Analysing collimator structure effects in head-scatter calculations for IMRT class fields using head scatter raytracing., " Phys. Med. Biol. 46, 2009-2028 (2001).