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

Roumani Alabd, Mitra Safavi-Naeini, Keenan J Wilson, Anatoly B Rosenfeld, Daniel R Franklin
2018 Physics in Medicine and Biology  
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
more » ... ployed 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.
doi:10.1088/1361-6560/aae33d pmid:30239336 fatcat:v6kgzglnxnd4je4rlydbt2cmza