ESTRO 2022 - Abstract Book

S1385

Abstract book

ESTRO 2022

Figure 1: Simplified functional cardiac atlas. The left ventricle is delineated in red, the right ventricle in dark green, the left auricle in light green, the left auricle in pink, the high-risk cardiac zone in green, the SAN in blue and the AVN in purple. A. Axial plane. B. 3D representation.

Figure 2: performance of atlas-based auto-segmentation of the proposed simplified functional cardiac atlas. DSC: Dice Similarity Coefficient. LA : left auricle. RA : right auricle. LV : left ventricle. RV : right ventricle. HRCZ : high risk cardiac zone. SAN : sinoatrial node. AVN : atrio-ventricular node. Conclusion We proposed a simplified functional cardiac atlas, for which coronary delineation difficulties were circumvent using a surrogate high risk cardiac zone and cardiac conduction system was considered. Most cardiac substructures were associated with acceptable ABAS properties. Such atlas could be potentially evaluated for epidemiological studies and clinical practice.

PO-1601 GPU accelerated Monte Carlo activation calculations for PET range verification in proton therapy

K. McNamara 1,2 , A. Schiavi 3 , K. Brzezinski 4 , D. Borys 4 , J. Gajewski 4 , A. Rucinski 4 , S. Makkar 1,2 , J. Hrbacek 1 , D.C. Weber 1,5,6 , A. Lomax 1,2 , C. Winterhalter 1,2 1 Paul Scherrer Institute, Centre for Proton Therapy, Villigen, Switzerland; 2 ETH Zürich, Physics Department, Zürich, Switzerland; 3 Sapienza University of Rome, Department of Basic and Applied Sciences for Engineering, Rome, Italy; 4 Polish Academy of Sciences, Institute of Nuclear Physics, Krakow, Poland; 5 University Hospital of Bern, Radiation Oncology Department, Bern, Switzerland; 6 University Hospital of Zürich, Radiation Oncology Department, Zürich, Switzerland Purpose or Objective To study the feasibility of range verification of proton therapy using PET detectors, Monte Carlo simulations of patient activation are necessary. Simulations are generally performed using CPU based Monte Carlo codes, such as Geant4, but are time consuming due to the complex physical processes, low likelihood of nuclear reactions requiring simulation of a large number of protons, and sequential CPU codes. Efficient and accurate simulations are therefore required. In this work