Probabilistic risk assessment of radiotherapy application

Abstract

The recent rapid development and increasing complexity of radiotherapy devices and applications has increased the importance of correct and safe treatment. Risk management is very important in radiotherapy (RT), because incorrect treatment can have serious consequences in terms of mortality or morbidity. However, there are currently few studies on risk analysis in RT. This quantitative and qualitative study of the radiotherapy system (all radiotherapy process) uses the fault tree method, one of the probabilistic risk assessment methods in radiotherapy applications, which is used to devise accident preventive actions. First of all, RT applications were divided into simulation, treatment planning and treatment delivery. For each, work flow charts were determined, and fault trees were created in SAPHIRE (Systems Analysis Programs for Hands-on Integrated Reliability Evaluations) software. Fault probabilities were determined using the expert judgment method. This analysis allowed the identification of the weak points of the system, both qualitatively and quantitatively. The analyzes also revealed that there was a 0.5% occurrence probability of a top event, determined as an incorrect dose or dose distribution in RT. It was determined that the greatest contribution to this probability value was matching error with image guidance, 7.88%. Fault tree analysis (FTA) was found to facilitate a detailed examination of the radiotherapy system. After the risk analysis, the appropriate quality control method for weak points should be determined and implemented for safety management in radiotherapy.

A Coupled Mathematical Model of the Dissemination Route of Short-Term Fund-Raising Fraud

“…Fault tree analysis (FTA) is a logical directed graph from result to cause. It can analyze the causes of accidents [23][24][25]. It is assumed that X i and T represent the variables of basic events and top events, and 0 or 1 can be taken to represent the occurrence and non-occurrence of events, respectively.…”

Vers de nouvelles recommandations en radioprotection : la CIPR en marche / Towards new recommendations in radiological protection: ICRP on the move

“…La médecine est un domaine majeur d'exposition aux rayonnements ionisants avec des enjeux de radioprotection importants pour les patients. En radiothérapie, outre l'évaluation probabiliste des risques (Thellier et al, 2021;Özbay et al, 2022), les modalités d'hypofractionnement avec des doses plus élevées par fraction soulèvent de nouvelles questions de radiobiologie (Bertho et al, 2021). En radiodiagnostic, le risque de leucémie associé aux examens scanners est de nouveau examiné (Asgari et al, 2021) alors que les résultats de la grande étude épidémiologique européenne EPI-CT concernant un excès de tumeurs cérébrales et de leucémies chez l'enfant sont attendus.…”

“…Medicine is a major field of exposure to ionizing radiation with significant radiological protection issues. In radiation therapy, besides the probabilistic risk assessment (Thellier et al, 2021;Özbay et al, 2022), the hypo fractionation modalities with higher dose per fraction raises new radiation biology issues (Bertho et al, 2021). In diagnostic radiology, the risk of leukemia associated with CT examinations is again examined (Asgari et al, 2021) while the results of the large European epidemiologic study EPI-CT study regarding an excess of brain tumors and leukemia in children are pending.…”