title: [Dynamic contrast-enhanced computed tomography. Tracer kinetics and radiation hygienic principles].
abstract: Technical innovations in multislice computed tomography (CT) allow for larger volume coverage in ever shorter scan times. This progress has stimulated the clinical application of dynamic contrast-enhanced (DCE) CT techniques, which offer the possibility to noninvasively characterize tissue microcirculation in terms of well-defined physiological quantities. This educational review imparts to radiologists the essential physiological terms and definitions as well as the basic tracer kinetic concepts required for the analysis of DCE-CT data. In particular, four different approaches are presented and exemplified by the analysis of representative DCE data: the steepest-gradient method, model-free algebraic deconvolution in combination with the indicator-dilution theory, two-compartment modelling and the so-called adiabatic approximation to the homogeneity model. Even though DCE-CT offers substantial methodological and practical advantages as compared to DCE-MRI (magnetic resonance imaging), there are also two serious and interconnected shortcomings: the low contrast enhancement in relation to the noise level and the high exposure of patients to ionizing radiation. These limiting aspects are considered in detail from a radiation hygienic point of view, emphasizing the basic principles of justification and optimization. Clinically established as well as potential future applications of DCE-CT will be presented in a subsequent paper.
authors.affiliation: Abteilung für Medizinischen und Beruflichen Strahlenschutz, Fachbereich Strahlenschutz und Gesundheit, Bundesamt für Strahlenschutz, Ingolstädter Landstr. 1, 85764 Neuherberg. gbrix@bfs.de
authors.forename: G
authors.initials: G
authors.lastname: Brix
authors.forename: J
authors.initials: J
authors.lastname: Griebel
authors.forename: S
authors.initials: S
authors.lastname: Delorme
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D003287:Contrast Media / Q000009:adverse effects / Q000493:pharmacokinetics*; D006801:Humans; D006920:Hygiene; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007700:Kinetics; D008954:Models, Biological; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media