L'exposition des patients en radiodiagnostic: Bilan de l'étude dosimétrique réalisée en 2001-2003 dans 24 services français de radiologie

Abstract

Within the frame work of implementation of Directive 97/43, a French dosimetry campaign in diagnostic radiology was carried out, from April 2001 to February 2003, under supervision of a steering Committee, involving representatives of scientific and professional societies, of the Directorate-General for Nuclear Safety and Radiation Protection (DGSNR) and experts of the Institute of Radiation Protection and Nuclear Safety (IRSN). The aim was to assess patient dose associated to the standardized radiology procedures recommended by the "Société française de radiologie" and to determine national dose reference levels (DRL) in diagnostic radiology. On the basis of protocols and data sheets established by the "Société française de physique médicale" and the IRSN, measurements were performed by multidisciplinary team (radiologist, physicists and radiographer) in 24 volunteer centers. The treatment of measured and collected data was in charge of the IRSN. For each of the 8 examinations selected, (4 in Conventional Radiology (CR) and 4 in Computed Tomography (CT)), data and dose measurements were assessed for 20 adult patients in each center. In CR, the entrance surface dose for each exposure was measured on 1231 patients using thermoluminescent dosimeters. In CT, the weighted Computed Tomography Dose Index and the Dose-Length Product were calculated for 667 patients, on base of the procedure parameters and the scanner normalized dose index values. For each type of examination, mean dose values and third quartile values were determined: depending on the type of examination, the results are either similar or lower than 1996 European DRL. These results are analyzed according the dose influencing parameters. Despite the 24 involved hospitals were not randomly selected, this preliminary study emphasizes the feasibility and great interest of a larger campaign of measurements based on a precise statistical survey of radiological practices in order to determine French DRL and to facilitate their periodic review in a continuous process of unnecessary doses reduction. © 2004 EDP Sciences.