title: Four-dimensional Monte Carlo simulation of time-dependent geometries.
abstract: Dynamic radiation therapy techniques require that the treatment head setup varies in time and space during dose delivery. Examples are leaf motion in intensity modulated x-ray therapy, modulator wheel rotation in conventional proton therapy and variable magnet settings in proton beam scanning. Consequently, for Monte Carlo dose calculation the results of several independent simulations usually have to be combined. Depending on the complexity and the required accuracy this can become cumbersome. We present a technique to simulate time-dependent geometries within a single four-dimensional Monte Carlo simulation using the GEANT4 Monte Carlo package. Results for proton therapy applications are shown.
authors.affiliation: Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. hpaganetti@partners.org
authors.forename: H
authors.initials: H
authors.lastname: Paganetti
mesh_terms: D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D009010:Monte Carlo Method; D009068:Movement; D061766:Proton Therapy; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D011881:Radiotherapy, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D011522:Protons
chemical_list: D011522:Protons