ASN Report 2017

268 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 09  - Medical uses of ionising radiation Teleradiology Teleradiology provides the possibility of guiding the performance and interpreting the results of radiology examinations carried out in another location. The interchanges must be carried out in strict application of the regulations (relating to radiation protection and the quality of image production and transfer in particular) and professional ethics. Essentially two methods of interchange are used: ཛྷ ཛྷ Telediagnosis, which enables a doctor on the scene (ex: an emergency doctor), who is not a radiologist, to perform the radiological examination and then send the images to a radiologist in order to obtain an interpretation. If necessary the radiologist can guide the radiological operator during the examination and imaging process. In this case, the doctor on the scene is considered to be the doctor performing the procedure and assumes responsibility for it. ཛྷ ཛྷ Tele-expertise, which is an exchange of opinions between two radiologists, where one asks the other – the “expert radiologist” (teleradiologist) – for a remote confirmation or contradiction of a diagnosis, to determine a therapeutic orientation or to guide a remote examination. The data transmissions are protected and preserve medical secrecy and image quality. Teleradiology involves many responsibilities which must be specified in the agreement binding the practitioner performing the procedure to the teleradiologist. The teleradiology procedure is a medical procedure in its own right, like all other imaging procedures, and cannot be reduced to a simple interpretation of images. Teleradiology therefore fits into the general healthcare organisation governed by the Public Health Code and obeys the rules of professional ethics in effect (see the good practices recommendations issued by the professionals). 1.1.2 Interventional practices using ionising radiation Interventional practices using ionising radiation (fluoroscopy- guided interventional practices) group “all the techniques using ionising radiation to perform invasive medical or surgical procedures for diagnostic, preventive and/or therapeutic purposes, and surgical and medical procedures using ionising radiation for the purpose of guidance or verification” . The devices used are either fixed devices installed in rooms dedicated to this activity, chiefly vascular specialities (neuroradiology, cardiology, etc.), or mobile radiology devices used in operating theatres in several surgical specialities, such as gastroenterology, orthopaedics and urology. The detectors present on the dedicated fixed devices and on the operating theatre radiology devices are image intensifiers or flat panel detectors. These devices employ techniques that use fluoroscopy and dynamic radiography (called “photofluorography”, or “cineradiography”) intended to produce high-resolution spatial images. After injecting a contrast agent, practitioners can also use the subtraction method to obtain images. Surgeons have recently started to use CT scanners, sometimes mobile, in the operating theatre. This type of equipment helps the practitioner perform the procedure by providing multi- plane images allowing virtual navigation. These scanners however are not equipped with the latest dose reduction technologies. The staff usually work in the immediate vicinity of the patient and are also exposed to higher dose levels than during other imaging practices. In these conditions, given the exposure risks for both the operator and the patient, practices must be optimised to reduce doses and ensure the radiation protection of operators and patients alike. ASN does not know exactly how many facilities are used for interventional procedures, mainly due to a rapid and recent increase in interventional practices in medical specialities as a whole in recent years. Only the numbers of rhythmology, interventional cardiology and interventional neuroradiology units are known with precision because these healthcare activities require an authorisation from the Regional Health Agency (ARS). The regional divisions of ASN moreover use the data on hospital activities to have better insight into the activities and the risks associated with medical imaging. More than 1,000 centres (lower bracket) practising interventional radiology and fluoroscopy-guided procedures have thus been inventoried in France. 1.1.3 Dental radiodiagnosis Intra-oral radiography Intra-oral radiography generators, which are usually mounted on an articulated arm, are used to take localised planar images of the teeth (the radiological detector is placed in the patient’s mouth). They operate with low voltage and current and a very short exposure time, of about a few hundredths of a second. This technique is most often associated with digital systems for processing and filing the radiographic images. The O-arm ® , new CT scanner for the operating theatre.