ASN Report 2017
269 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 09 - Medical uses of ionising radiation Panoramic dental radiography Panoramic radiography (orthopantomography) gives a single picture showing both jaws in full, by rotating the radiation generating tube around the patient’s head for a few seconds. Cone-beam computed tomography Cone-beam computed tomography (3D) is developing very rapidly in all areas of dental radiology, due to the exceptional quality of the images produced (spatial resolution of about 100 microns). The trade-off for this better diagnostic performance is that these devices deliver significantly higher doses than in conventional dental radiology. Portable X-ray generating devices ASN and the Dental Radiation Protection Commission (CRD) published an information notice in May 2016 2 reiterating the rules associated with the possession and utilisation of portable X-ray generating devices. They draw attention to the fact that “the performance of radiological examinations outside a room fitted out for that purpose must remain the exception and be justified by vital medical needs, limited to intraoperative examinations or for patients who cannot be moved. Routine radiology practice in a dental surgery equipped with a compliant facility shall not be carried out using mobile or portable devices” . This position is supported by that of HERCA (Heads of the European Radiological protection Competent Authorities), for which the use of such devices should be reserved for incapacitated patients, forensic medicine and military field operations ( HERCA Position Statement on use of handheld portable dental x-ray equipment, June 2014). 1.2 Technical rules for fitting out radiology and tomography installations Radiology installations A conventional radiological facility usually comprises a generator (high-voltage unit, X-ray tube), associated with a support (the stand) for moving the tube, a control unit and an examination table or chair. Mobile facilities, but which are often always used in the same room, such as the X-ray generators used in operating theatres, are to be considered fixed facilities. Radiological facilities must be fitted out in accordance with the provisions of the new ASN technical resolution 2017-DC-0591 of 13th June 2017 (see chapter 3). This decision applies to all medical radiology facilities, including computed tomography and dental radiology. It does not however apply to X-ray generators that are used exclusively for bedside radiography. 2 . www.asn.fr/Informer/Actualites/Appareils-electriques-portables-rappel-de-l- ASN-et-de-la-Commission-Radioprotection-Dentaire 2. Nuclear medicine 2.1 Presentation of nuclear medicine activities Nuclear medicine includes all uses of unsealed radioactive sources for diagnostic or therapeutic purposes. Diagnostic uses can be divided into in vivo techniques, based on administration of radionuclides to a patient, and exclusively in vitro applications (medical biology). Functional exploration examinations can combine in vitro and in vivo techniques. About 1,460,000 procedures were carried out in 2016 3 , including 406,000 Positron Emission Tomography (PET) examinations. Nuclear medicine comprises slightly more than 700 specialist practitioners, along with another 1,000 or so physicians from other specialities working together in nuclear medicine units (interns, cardiologists, endocrinologists, etc.). At the end of 2016, this sector of activity comprised 232 nuclear medicine units accommodating the associated in vivo and in vitro facilities. Nearly 160 automated or semi- automated devices for preparing radiopharmaceuticals marked with fluorine-18 and as many injection devices are used. Some fifty in vitro diagnostic laboratories were inventoried in 2017, but this number is tending to drop due to the gradual phasing out of this activity in favour of methods that do not use radionuclides. For therapeutic purposes, there are 157 Internal Targeted Radiotherapy (ITR) hospital rooms spread over 45 nuclear medicine units 4 . Medical dispensaries are mandatory in public health institutions. The radiopharmaceutical preparation room, called the “radiopharmacy” within the nuclear medicine department, is part of the dispensary. There are 128 nuclear pharmacies among the 232 nuclear medicine departments. The radiopharmacist is primarily responsible for managing the medication circuit (procurement, possession, preparation, dispensing and traceability) and can be assisted by a hospital dispensary preparation technician or by radiographers. 3 . Dashboard of the SFMN (French Society of Nuclear Medicine and Molecular Imaging): www.sfmn.org/drive/SECRETARIAT%20GENERAL/ENQUETE_ ANNUELLE/EnqueteNationale2016_publicWeb.pdf 4 . Source: ASN review of nuclear medicine department inspections (2016).