Dictionary-based protoacoustic dose map imaging for proton range verification

Proton radiotherapy has the potential to provide state-of-the-art dose conformality in tumor area, reducing possible adverse effects on surrounding organs at risk. However, uncertainties exact location of proton Bragg peak inside patient prevent this technique from achieving full clinical potential. In context, vivo verification range protons patients is key reduce uncertainty margins. Protoacoustic employs acoustic pressure waves generated by due radio-induced thermoacoustic effect reconstruct deposited a during therapy. paper, we propose use priori knowledge shape distribution create dictionary with expected ultrasonic signals predetermined detector locations. Using dictionary, reconstruction performed matching pre-calculated data acquired online treatment. The method was evaluated single-field plan for prostate cancer patient. Dose calculation open-source treatment planning system matRad, while wave propagation carried out k-Wave. We studied ability proposed detect variations caused anatomical changes tissue density, and alterations lateral longitudinal beam position. Our results show that dictionary-based protoacoustic able identify originated all introduced, an average accuracy 1.4 mm. This procedure could be used verification, comparing measured precalculated dictionary.