Prog Med Phys.  2015 Mar;26(1):36-41. 10.14316/pmp.2015.26.1.36.

Calculation of Dose Distribution for SBRT Patient Using Geant4 Simulation Code

• Kang J
• Lee J
• Lee DJ

• KMID: 2315776
• DOI: http://doi.org/10.14316/pmp.2015.26.1.36

Abstract

The Monte Carlo based dose calculation program for stereotactic body radiotherapy was developed in this study. The Geant4 toolkit widely used in the radiotherapy was used for this study. The photon energy spectrum of the medical linac studied in the previous research was applied for the patient dose calculations. The geometry of the radiation fields defined by multi-leaf collimators were taken into account in the PrimaryGeneratorAction class of the Geant4 code. The total of 8 fields were demonstrated in the patient dose calculations, where rotation matrix as a function of gantry angle was used for the determination of the source positions. The DicomHandler class converted the binary file format of the DICOM data containing the matrix number, pixel size, endian type, HU number, bit size, padding value and high bits order to the ASCII file format. The patient phantom was constructed using the converted ASCII file. The EGSnrc code was used to compare the calculation efficiency of the material data.

Keyword

Monte Carlo; dicom; SBRT; Geant4

MeSH Terms

Humans
Radiosurgery
Radiotherapy

Figure

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  Fig. 1. The isodose distributions for the center slice of the CT data. (a) dose distributions from iPLan, (b) dose distributions in this study.

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  Fig. 2. Dose distributions of the lateral slices, (a) dose distributions from iPLan, (b) dose distributions in this study.

Reference

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