Effect of different embolization materials on proton beam stereotactic radiosurgery Arteriovenous Malformation dose distributions using the Monte Carlo simulation code

Recently, radiation therapy with protons has received much attention. In 2020, nearly 250,000 patients in 110 centers around the world preferred radiation therapy with protons for treatment. One of them, proton-based stereotactic radiosurgery, is a treatment option after surgical interventions in Arteriovenous Malformation (AVM). The main goal of this research is to compute the amount of linear energy transfer (LET) delivered to the target because the highly preferred liquid embolic agents weaken the proton beam. LET, recoils, lateral straggle and crystalline vanacies accumulated by three different embolization materials: Ethylene vinyl alcohol (On), Cyanoacrylate (Ca) and polyvinyl alcohol (Pa) were analysed with an aim to calculate the ionization, rebound, phonon and lateral straggle of the brain at different depths for a 2 cm diameter AVM using Monte Carlo-based simulation. The obtained data were evaluated and the results compared against water. The closest Bragg peak value to water was found in Ca with a 4.1% difference. The closest to water in beam range was On with 0.9% difference. The highest recoils value was observed in PVA embolization material. The lowest lateral straggle value at all beam energy levels was in PVA embolization material.