Certain brachytherapy dose distributions, such as those for LDR prostate implants, are readily modeled by treatment planning systems (TPS) that use the superposition principle of individual seed dose distributions to calculate the total dose distribution. However, dose distributions for brachytherapy treatments using high-Z shields or having significant material heterogeneities are not currentl...

As technology continues to develop, external beam radiation therapy is being employed, with increased conformity, to treat smaller targets. As this occurs, the dosimetry methods and tools employed to quantify these fields for treatment also have to evolve to provide increased spatial resolution. The team at the University of Wollongong has developed a pixelated silicon detector prototype known ...

A method is described for computing patient-specific absorbed dose rates to active marrow which accounts for spatial variation in bone volume fraction and marrow cellularity. A module has been added to the 3D Monte Carlo dosimetry program DPM to treat energy deposition in the components of bone spongiosa distinctly. Homogeneous voxels in regions containing bone spongiosa (as defined on CT image...

BACKGROUND Megavoltage beams used in radiotherapy are contaminated with secondary electrons. Different parts of linac head and air above patient act as a source of this contamination. This contamination can increase damage to skin and subcutaneous tissue during radiotherapy. Monte Carlo simulation is an accurate method for dose calculation in medical dosimetry and has an important role in optim...

In the megavoltage energy range although the mass attenuation coefficients of different bones do not vary by more than 10%, it has been estimated that a simple tissue model containing a single-bone composition could cause errors of up to 10% in the calculated dose distribution. In the kilovoltage energy range, the variation in mass attenuation coefficients of the bones is several times greater,...

A Strategic Research project was performed at NPL with the aim of investigating issues and potential improvements for light-ion dosimetry. The objectives of the project were: a literature survey, testing a number of dosimeters in the proton therapy beam of Clatterbridge Centre of Oncology (CCO), measurement of dose distributions, measurement and calculation of detector perturbations, explore th...