ESTRO 2021 Abstract Book

S1426

ESTRO 2021

All dosimeters results were lower than the 0.1 mSv detection threshold. So, one dosimeter was worn by a category (e.g. one ring for all surgeons). Even though, results were still lower than threshold: measured dose for a year is lower than 0.4 mSv, even for the anatomopathologist extremities. The reason for the dose difference between evaluation and measurement may be the overestimation of time needed to ink and segment the exeresis. Conclusion Changing from a cold location technique such as metal guide to a radioactive seed implant can be safely realised regarding patients and workers with the involvement of the whole multidisciplinary team. Multicenter trial can be challenging, especially when it includes strong regulatory obligations; French national nuclear safety and radiation protection authority was supportive in this original approach. From our experience, the iodine seed technique improves the organisational flexibility and the patient comfort. At the end of the inclusions, clinical trial results will allow to conclude on the expected benefits regarding surgical quality. PO-1699 continuous quality improvement and performance assessment in radiotherapy; system thinking approach S. Abdollahi 1 , F. Varshoee 2 , Y. Makhdoumi 2 , F. Jamali 1 , L. Sobhkhiz Sabet 1 1 Reza Radiotherapy & Oncology Center, Medical Physics, Mashhad, Iran Islamic Republic of; 2 Reza Radiotherapy & Oncology Center, Radiation Oncology, Mashhad, Iran Islamic Republic of Purpose or Objective While continuous improvement and performance assessment are major concerns in most radiotherapy departments, the multidisciplinary and complex nature of radiotherapy makes the assessment a challenging managerial task as the relation between different variables and their mutual effects are not clear and the results of any intervention over time are not easy to evaluate. The aim of the study was to investigate if a holistic systemic approach can improve the ability to understand current practice, predict the system behavior, and design modifications to improve the performance.

Materials and Methods the whole radiotherapy processes were mapped to analyze each part of the chain and the strengths and weaknesses in the existing processes were identified. The process mapping was performed for admission, imaging, treatment planning, dosimetry, and treatment parts via a series of meetings with key personnel in charge of each section and the whole process was reviewed and approved by the quality management team. The cause and effect relationships between different parts of the chain were studied using a causal loop diagram (CLD) mapped by Vensim software to reveal the key feedback structure of the treatment dynamics