ESTRO 2024 - Abstract Book

S5867

RTT - Service evaluation, quality assurance and risk management

ESTRO 2024

Conclusion:

The integration of the bow-tie model into the risk analysis within radiotherapy made it possible to have a good visualization of the causes, barriers, and consequences on the three critical events analyzed. This model provides a better understanding of the risk presentation and protection needed to ensure patient safety within radiotherapy. Integrating this model also provided valuable insights to identify weak links and contributing factors that might otherwise be overlooked in traditional risk analysis such as Failure Mode, Effects and Criticality Analysis (FMECA). By using this method, the radiotherapy department is equipped with an effective tool to strengthen the safety of patient care on the one hand and to take preventive measures on the other hand for the proper functioning of its processes.

Keywords: patient safety, bow-tie methodology, radiotherapy

224

Digital Poster

Targeting accuracy of image-guided HyperArc plans using resampled planning CT and CBCT images

Coral Laosa-Bello 1 , Antonia Zamora-Pérez 1 , Claudia López-Alario 1 , Sandra Moragues-Femenia 1 , Juan-Francisco Calvo Ortega 1,2 1 Hospital Quirónsalud Barcelona, Radiation Oncology, Barcelona, Spain. 2 Hospital Quirósalud Málaga, Radiation Oncology, Málaga, Spain

Purpose/Objective:

The simulation CT (CTsim) scan required for cranial SRS planning using the Varian HyperArc technique must include the patient's shoulders to feed its collision algorithm (Fig 1). Therefore, using the 1 mm slice thickness of our radiosurgery procedure, the CTsim scan can contain up to ~350 slices, while the Portal Vision Advance (PVA) software of the TrueBeam v. 2.7 platform can load 250 slices only. To overcome this issue, the PVA performs resampling of the CTsim down to 250 slices by increasing the slice thickness beyond 1 mm. In addition, the 1 mm slice thickness CBCT, acquired to be registered online with the CTsim, is also resampled to match the slice thickness of the resampled CTsim.

This study aims to evaluate the targeting accuracy of the online CBCT-guided HyperArc plans based on resampled CTsim and CBCT scans having a slice thickness larger than 1 mm.