Dose calculations with the BEAM Monte Carlo code at extended SSDs

Author

Stathakis, Sotirios ; Kappas, Constantin ; Papanikolaou, Nikos

Author_Institution

Dept. of Med. Phys., Patras Univ., Greece

Volume

3

fYear

2000

fDate

2000

Firstpage

1679

Abstract

Extended Surface to Skin Distance (SSD) beam data are very useful for hemibody and total body irradiation. Monte Carlo simulation provides an alternative mechanism to calculate the dose for such treatment modalities. Comparison of the Monte Carlo results has been done with measured data of two linear accelerators of 6 MV, with results from two commercial 3D treatment-planning systems and with extrapolated data from measurements at 100 cm SSD. The results from the Monte Carlo simulations agreed with the experimental results within 1% and the PDD curves produced from the TPSs were within 2% error. The extrapolated PDD curves had a deviation of about 2%. It was found that d_max migrated towards the surface with increasing SSD which was predicted by the simulations. Also, the mean photon energy as computed by the simulation was found to be higher at extended SSD which is part of the reason why the PDDs are more penetrating for extended distances

Keywords

Monte Carlo methods; dosimetry; extrapolation; photon transport theory; radiation therapy; skin; 3D treatment-planning systems; 6 MV; BEAM Monte Carlo code; Monte Carlo simulation; dose calculations; extended surface to skin distance; extrapolated data; hemibody irradiation; linear accelerators; mean photon energy; off axis ratios; percent depth dose; primary fluence; radiotherapy treatment planning; scatter fluence; spectral distribution; total body irradiation; Computational modeling; Geometry; Linear accelerators; Monte Carlo methods; Optical computing; Performance evaluation; Predictive models; Skin; Solid modeling; Surface treatment;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society, 2000. Proceedings of the 22nd Annual International Conference of the IEEE

Conference_Location

Chicago, IL

ISSN

1094-687X

Print_ISBN

0-7803-6465-1

Type

conf

DOI

10.1109/IEMBS.2000.900402

Filename

900402