A simulation study of BrachyShade, a shadow-based internal source tracking system for HDR prostate brachytherapy

Authors

Roumani Alabd, University of Technology Sydney
Mitra Safavi-Naeini, Australian Nuclear Science and Technology Organisation
Keenan Wilson, University of Technology Sydney
Anatoly B. Rosenfeld, University of WollongongFollow
Daniel R. Franklin, University of Technology SydneyFollow

RIS ID

133835

Publication Details

Alabd, R., Safavi-Naeini, M., Wilson, K. J., Rosenfeld, A. B. & Franklin, D. R. (2018). A simulation study of BrachyShade, a shadow-based internal source tracking system for HDR prostate brachytherapy. Physics in Medicine and Biology, 63 (20), 205019-1-205019-15.

Abstract

This paper presents a simulation study of BrachyShade, a proposed internal source-tracking system for real time quality assurance in high dose rate prostate brachytherapy. BrachyShade consists of a set of spherical tungsten occluders located above a pixellated silicon photodetector. The source location is estimated by minimising the mean squared error between a parametric model of the shadow image and acquired images of the shadows projected on the detector plane. A novel algorithm is finally employed to correct the systemic error resulting from Compton scattering in the medium. The worst-case error obtained with BrachyShade for a 13.5 ms image acquisition is less than 1.3 mm in the most distant part of the treatment volume, while for 75% of source locations an error of less than 0.42 mm was achieved.