The Quality Criteria for Computed Tomography

Abstract

Radiation exposure to the patient during CT is relatively high. It is therefore important to optimise the dose to be as low as consistent with required diagnostic image quality. The quality criteria concept as developed for conventional X ray examination of adult and paediatric patients has been proved to be an effective method for optimising the use of ionising radiation in medical imaging procedures In an EU working document, EUR 16262, regarding Quality Criteria for CT this concept has been used to provide an operational framework for radiation protection initiatives in which technical parameters required for adequate image quality are considered in relation to patient dose. The document includes diagnostic requirements specifying anatomical/diagnostic image quality criteria for six main groups of examinations: cranium, face and neck, spine, chest, abdomen and pelvis, and bones and joints (pelvis and shoulder). The image criteria refer to characteristic features of imaged anatomical structures that tire defined in the region of examination with a specific degree of visibility The production of diagnostic quality criteria was, for the retroperitoneal space, the mediastinum and the brain, partly based on preliminary clinical analyses of image quality criteria performed in one institution. The usability of the quality criteria in daily clinical practice has to be evaluated further. Therefore a multicentre clinical pilot study evaluating the use of quality criteria, including radiation dose measurement, has been initiated.