EuroSafe Imaging 2020
Not applicable, Dosimetric comparison, Dosimetry, Cone beam CT, Radioprotection / Radiation dose, Interventional vascular, Interventional non-vascular, Action 9 - Facilitation of research in advanced topics of radiation protection
T. Russ, A. M. Abdelrehim, D. F. Bauer, S. Hatamikia, L. R. Schad, F. Zöllner, K. Chung
Conclusion and recommendations
The proposed framework enables the simulation of CBCT image quality and physical dose maps depending on the acquisition orbit. Accurate MTF determinations using oversampled LSFs revealed efficient alternatives to the standard circular scan trajectory in the imaging scenario of robot-assisted surgery. In addition, the possibility to calculate deposited dose to the patient using GATE simulations was demonstrated.
In future work, the major issue of insufficient photon counts in the GATE projections needs to be addressed by increasing the number of primary photons up to tenfold. This can possibly raise the simulation time to up to 30 days. Besides, the simulation framework will be extended to include a homogeneous water phantom in order to determine the noise power spectrum (NPS). In combination with the MTF, the detectability index can thus be calculated and will provide a more comprehensive evaluation of the task-based image quality. In addition, the dose to the immediate interventional environment will be simulated to enable the visualization of trajectory-dependent dose hotspots in the intervention room. This can help to minimize personnel dose and thus increase imaging safety.