ASN Report 2017

286 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 09  - Medical uses of ionising radiation 5.7.2 Radiation protection of patients The findings established from the inspections in 2016 with regard to patient radiation protection also confirmed the observations made over the last few years. Shortcomings were observed in the application of the dose optimisation principle, be it in the setting of the machines and the protocols used or in the practices. They resulted firstly from insufficient training and secondly from a lack of optimisation of the available protocols with a view to improving patient radiation protection. A distinct improvement was however observed in the fixed facilities, particularly in cardiology and neuroradiology, where widespread implementation of dosimetric reviews has fostered dose optimisation. Reference levels for the most common examinations were being developed locally more and more often. This approach also enables, among other things, alert levels to be set to trigger appropriate medical monitoring of the patient according to the dose levels received. The Dose Archiving and Communication Systems (DACS) currently being deployed facilitate the development of local reference levels and alert levels per machine and per type of procedure. These DACS’s are a valuable means of tracking the doses previously received by the patient and of monitoring the patient. Practitioners in the operating theatre rarely have access to a dose indicator during their intervention. The medical personnel had insufficient knowledge of the reference dose levels for the type of procedure performed. The operating theatre C-arm units, due to their mobility, were more rarely connected to the DACS of the centre than the fixed facilities in the interventional rooms. Insufficient use of medical physicists in departments practising fluoroscopy-guided interventional procedures was still hindering application of the optimisation principle. Greater involvement of the medical physicist would, among other things, enable the equipment to be better used, with the establishing of appropriate protocols for the procedures performed and the development of dosimetric reference levels. When medical centres called upon outside medical physics service providers, it was observed that the centres rarely adopted the procedures and documentation proposed by these service providers. 5.7.3 Significant events notified in the area of fluoroscopy-guided interventional practices 24 significant events were notified in the area of fluoroscopy- guided interventional practices in 2017. Among these events: ཛྷ ཛྷ Five events concerned workers. They reported cases of exceeding the projected doses evaluated during the working environment analysis or exceeding the permissible regulatory dose limits for the whole body and/or the extremities. ཛྷ ཛྷ Nine events concerned overexposure of patients, some of which led to deterministic effects such as transient alopecia (hair loss) or erythema. ཛྷ ཛྷ Four events concerned pregnant patients exposed during a fluoroscopy-guided interventional examination. In most cases the exposed woman was unaware of her pregnancy. ཛྷ ཛྷ Six events concerned the equipment (lead apron, dosimeter, radiology table, theft of equipment). Three ESRs concerning interventional practitioners who received doses to the extremities (hands) exceeding the regulatory dose limit were notified in late 2017 and rated level 2 on the INES scale. These events highlighted the deficiencies in the organisation of occupational radiation protection. The centres in question will be inspected in early 2018 to get a fuller idea of their practices. ASN inspection of the nuclear medicine unit of the Eugène-Marquis regional cancer centre in Rennes, July 2015.