title: Evaluation of the spatial resolution with 1.5-4 tesla in a stenosis model.
abstract: Since it was first described in the early 1990s, magnetic resonance coronary angiography has evolved into a promising noninvasive modality for imaging the coronary arteries. The aim of this study was to evaluate the detection accuracy and spatial resolution of vascular stenosis in contrast-enhanced 3-dimensional magnetic resonance angiography on a flow phantom. The examinations were performed with 1.5, 3, and 4 T whole-body imaging systems. For imaging at 4 T, we used a gradient-echo-multi-slice sequence. The system was flushed with gadopentetate dimeglumine contrast medium at flow rates of 40 and 60 mL.min(-1). The accurate detection of in vitro stenoses was possible in segments of 0.4 mm in diameter at 4 T. The best results were obtained at a flow velocity of 40 mL.min(-1) and a contrast medium concentration of 0.2 mmol.L(-1). Contrast-enhanced high-field 3-dimensional magnetic resonance imaging provided a highly accurate evaluation of the degree of stenosis in this model. Exact evaluation of vessel diameters < 0.4 mm was not possible, even with 4 T. In vivo studies are necessary to overcome the current limitations in the visualization of small distal vessel segments.
authors.affiliation: , Department of Thoracic and Cardiovascular Surgery, University Hospital, Theodor-Stern-Kai 7, Frankfurt 60590, Germany. thomaswittlinger@t-online.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wittlinger
authors.forename: Ivo
authors.initials: I
authors.lastname: Martinovic
authors.forename: Anton
authors.initials: A
authors.lastname: Moritz
authors.forename: Sandro
authors.initials: S
authors.lastname: Romanzetti
mesh_terms: D023921:Coronary Stenosis / Q000175:diagnosis*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008280:Magnetics; D008955:Models, Cardiovascular; D019047:Phantoms, Imaging