Konzepte zur Charakterisierung klinischer CT-Systeme unter Einbeziehung von Bildqualität und Dosis

In Germany, as in most Western countries, the exposure to the population due to CT examinations has increased over the last twenty years, despite major technological progresses which might lead to the expectation that doses would decrease. The last survey organized in Germany showed that in 2014 the average dose per inhabitant due to CT was 1.0 mSv compared to 0.8 mSv in 2007. Thus, the use of CT is a major source of concern for Public Health Authorities such as the “Bundesamts für Stahlenchutz” in Germany. Among the ways to control the population exposure creeping upwards one should ensure that the principle of justification is correctly applied and that the radiological examination and intervention are optimized in terms of the balance of low dose against required image quality. In the context of optimization, the units used should work efficiently to ensure that there is no waste of radiation in the imaging process. The aim of this project is to propose a way to benchmark CT units, allowing the assessment of the efficiency of CT units using clinically relevant protocols. The project was made of four work-packages. The first work-package was a review of the literature dedicated to image quality assessment in CT imaging. During this work-package the clinically relevant protocols used for benchmarking were also defined. The second work-package was dedicated to the set-up of the methodology to be used when dealing with the benchmarking of CT units using two different concepts. The third work-package was the application of these concepts on eight CT units; including two models from each of four manufacturers. Finally, the fourth work-package consisted in the analysis of the data with the proposal of a strategy to establish a dose efficiency index (DEI) to quantify the CT unit performances