Sensitivity of large-field electron beams to variations in a Monte Carlo accelerator model. Export

@article{Schreiber2005, abstract = {Adjustments made to Monte Carlo models during the commissioning of the simulation should be physically realistic and correspond to actual machine characteristics. Large electron fields, with the jaws fully open and the applicator removed, are sensitive to important source and geometry parameters and may provide the most accurate beam models, including those collimated by an applicator. We report on the results of a comprehensive Monte Carlo sensitivity study documenting the response of these large fields to changes in the configuration of a Siemens Primus linear accelerator. The study was performed for 6, 9 12, 15, 18 and 21 MeV configurations, and included variations of thickness, position and lateral alignment of all treatment head components. Variations of electron beam characteristics were also included in the study. Results were classified by their impact on central-axis depth dose distributions, including the bremsstrahlung tail, and on beam profiles near D(max) and in the bremsstrahlung region. Low-energy results show an increased sensitivity to electron beam properties. High-energy bremsstrahlung profiles are shown to be useful in determining misalignments between the beam axis and mechanical isocentre. For all energies, the alignment of the secondary scattering foil and monitor chamber are shown to be critical for correctly modelling beam asymmetries. The results suggest a methodology for commissioning of electron beams using Monte Carlo treatment head simulation.}, author = {Schreiber, E. C. and Faddegon, B. A.}, citeulike-article-id = {2990628}, citeulike-linkout-0 = {http://dx.doi.org/10.1088/0031-9155/50/5/003}, doi = {10.1088/0031-9155/50/5/003}, journal = {Phys Med Biol}, keywords = {accelerators, and, carlo, computer-assisted, dosage, electrons, method, models, monte, particle, photons, planning, radiation, radiotherapy, scattering, sensitivity, specificity, theoretical}, month = {Mar}, number = {5}, pages = {769--778}, posted-at = {2008-07-11 21:11:30}, priority = {2}, title = {{S}ensitivity of large-field electron beams to variations in a {M}onte {C}arlo accelerator model.}, url = {http://dx.doi.org/10.1088/0031-9155/50/5/003}, volume = {50}, year = {2005} }

TY - JOUR ID - Schreiber2005 L3 - citeulike-article-id:2990628 N2 - Adjustments made to Monte Carlo models during the commissioning of the simulation should be physically realistic and correspond to actual machine characteristics. Large electron fields, with the jaws fully open and the applicator removed, are sensitive to important source and geometry parameters and may provide the most accurate beam models, including those collimated by an applicator. We report on the results of a comprehensive Monte Carlo sensitivity study documenting the response of these large fields to changes in the configuration of a Siemens Primus linear accelerator. The study was performed for 6, 9 12, 15, 18 and 21 MeV configurations, and included variations of thickness, position and lateral alignment of all treatment head components. Variations of electron beam characteristics were also included in the study. Results were classified by their impact on central-axis depth dose distributions, including the bremsstrahlung tail, and on beam profiles near D(max) and in the bremsstrahlung region. Low-energy results show an increased sensitivity to electron beam properties. High-energy bremsstrahlung profiles are shown to be useful in determining misalignments between the beam axis and mechanical isocentre. For all energies, the alignment of the secondary scattering foil and monitor chamber are shown to be critical for correctly modelling beam asymmetries. The results suggest a methodology for commissioning of electron beams using Monte Carlo treatment head simulation. IS - 5 JF - Phys Med Biol EP - 778 TI - {S}ensitivity of large-field electron beams to variations in a {M}onte {C}arlo accelerator model. VL - 50 SP - 769 KW - accelerators KW - and KW - carlo KW - computer-assisted KW - dosage KW - electrons KW - method KW - models KW - monte KW - particle KW - photons KW - planning KW - radiation KW - radiotherapy KW - scattering KW - sensitivity KW - specificity KW - theoretical AU - Schreiber, EC AU - Faddegon, BA PY - 2005/Mar// UR - http://dx.doi.org/10.1088/0031-9155/50/5/003 ER -