1.5 Significant radiation protection events It is mandatory to report ESRs to ASN in application of the Public Health Code (Articles L. 1333‑13, R. 1333‑21 and 22) and the Labour Code (Article R. 4451‑74) (see chapter 3, point 3.3). In the medical field, ESRs have been reported to ASN since 2007. Reporting these events makes it possible, after analysing them, give feedback to the medical professionals with a view to continuous improvement of radiation protection. An on-line services portal has been provided at Teleservices.asn.fr to enable all the medical professionals to file reports on line. This portal is integrated in the “one-stop vigilance portal” managed by the Ministry of Solidarities and Health. Depending on the type of event reported, the notification is sent automatically to ASN (regional division), to the Regional Health Agency (ARS) for all events concerning the patient, while events relating to medical devices vigilance or drug safety monitoring (RPDs) are sent to the ANSM. ASN Guide No. 11 specifies the procedures for reporting significant radiation protection events. ASN Guide No. 16 applies specifically to the reporting of ESRs concerning patients that occur in the field of radiotherapy (external-beam radiotherapy and brachytherapy). A specific scale, the ASN-SFRO scale has been developed in collaboration with the French Society for Radiation Oncology (SFRO) to inform the public about radiation protection events affecting patients undergoing radiotherapy procedures (see chapter 3). In addition to the confirmed consequences, it enables the potential effects of the event and number of patients exposed to be taken into consideration. Moreover, the incident notices are published on asn.fr. To encourage the sharing of the lessons learned from experience feedback from the medical professionals, ASN has published the newsletter Patient safety –Paving the way for progress since March 2011, Experience feedback from ESR sheets and circular letters addressed to the heads of nuclear activities. Produced by multidisciplinary working groups coordinated by ASN, the newsletter offers a thematic presentation of the good practices of medical departments and the recommendations developed by the learned societies of the discipline concerned and the health and radiation protection institutions. The “Experience feedback” sheet, for its part, draws attention to a specific ESR reported to ASN to prevent it from occurring in another centre. 2 // Nuclear-based medical activities 2.1 External-beam radiotherapy Radiotherapy, along with surgery and chemotherapy, is one of the key techniques employed to treat cancerous tumours. Radiotherapy uses ionising radiation to destroy malignant cells (and non-malignant cells in a small number of cases). The ionising radiation necessary for the treatments is produced by an electric generator or emitted by radionuclides in sealed sources. We distinguish external-beam radiotherapy, where the source of radiation (particle accelerator or a radioactive source such as Gamma knife®) is external to the patient, from brachytherapy, where the source is placed as close as possible to the cancerous lesion. The radiation sessions are always preceded by the preparation of a treatment plan which serves to set the conditions for achieving a high dose in the target volume while preserving the surrounding healthy tissues. The treatment plan defines the dose to deliver, the target volume(s) to treat, the volumes at risk to be protected, the ballistics of the radiation beams and the predicted dose distribution (dosimetry). Preparation of the treatment plan requires close cooperation between the radiation oncologist, the medical physicist and, if necessary, the dosimetrists. The main radiation protection risk is linked to the dose delivered to the patient; the change of treatment techniques with the development of hypofractionated radiotherapy (see point 2.1.1), which consists in delivering higher doses during a given session, makes it all the more crucial to control delivery of the dose. This is why ASN’s oversight focuses on both the ability of the centres to control delivery of the dose to the patient and to learn lessons from the malfunctions that could occur. Implementation of the treatment quality and safety management system, skills management, mastery of the equipment, ESR recording and follow-up are the focal points of the ASN inspections. As tech– nical, organisational and human changes have been identified as potential risk-generating situations, particular attention is also given to change management during the inspections. 2.1.1 Presentation of the techniques Several external-beam therapy techniques are currently used in France. The SFRO considers three-dimension conformal radio– therapy to be the basic technique in its Guide to recommendations for the practise of external-beam radiotherapy and brachytherapy (Recorad) published in September 2016 and updated in February 2022. This technique uses three-dimensional images of the target volumes and neighbouring organs obtained with a CT scanner, sometimes in conjunction with other imaging examinations (Positon Emission Tomography –PET, Magnetic TABLE Frequency of inspections per area of nuclear-based medical activity NUCLEAR-BASED MEDICAL ACTIVITY ROUTINE FREQUENCY External-beam radiotherapy Every 4 years Brachytherapy Every 4 years Diagnostic nuclear medicine Every 5 years Therapeutic nuclear medicine on out-patient basis (e.g. iodine <800megabecquerels (MBq), synoviortheses, etc.) Every 4 years Therapeutic nuclear medicine with complex therapies using iodine >800 MBq, of lutetium-177, yttrium-90 and hospitalisation Every 3 years Fluoroscopy-guided interventional practices Every 5 years Computed tomography (emergencies or paediatrics) Sampling: about twenty facilities per year 2 ASN Report on the state of nuclear safety and radiation protection in France in 2021 209 07 – MEDICAL USES OF IONISING RADIATIONS 08 07 13 04 10 06 12 14 03 09 05 11 02 AP 01
RkJQdWJsaXNoZXIy NjQ0NzU=