title: [Experimental evaluation of vessel diameter from 0.3 to 8 mm in CE MR angiography].
abstract: OBJECTIVE
  To evaluate the detection rate of vascular stenosis in contrast-enhanced 3D MR angiography using a flow phantom.
  
  
  METHODS
  The examinations were performed on a 1.5 T whole body imaging system (Magnetom Symphony/Quantum) with 30 mT/m gradient field strength using a body-phased-array coil. Different 3D sequences (TR/TE/FA < 5 ms/< 2 ms/25 degrees ) with slice thicknesses ranging from 0.67 to 1.25 mm were applied. A gelantine-filled plastic cylinder with PVC tubes of 8 mm diameter was used as a vascular phantom. The tubes had concentric and excentric stenoses (50 - 90 %) of different lengths. For the detection of different vessel diameters another phantom with 0.3 - 8 mm silicon tubes was used. Both systems were flushed with a solution of Gd-DTPA (0.15 mmol/l) and saline at flow rates from 50 to 200 cm/s. The phantoms were positioned 0 degrees, 45 degrees, and 90 degrees towards the z-axis.
  
  
  RESULTS
  The degree of stenosis was under- and overestimated in less than 10 %. The sequence with the highest spatial resolution provided the best results. Detection and evaluation of tubes >/= 2 mm proved to be reliable.
  
  
  CONCLUSIONS
  Contrast-enhanced 3D MR angiography provides an almost exact evaluation of the degree of stenosis in the phantom study. Evaluation of vessel diameters < 2 mm is not possible.
authors.affiliation: Abt. Röntgendiagnostik I, Klinikum der Georg-August-Universität Göttingen. roe1@med.uni-goettingen.de
authors.forename: R
authors.initials: R
authors.lastname: Vosshenrich
authors.forename: B
authors.initials: B
authors.lastname: Engeroff
authors.forename: C
authors.initials: C
authors.lastname: Müller
authors.forename: U
authors.initials: U
authors.lastname: Fischer
authors.forename: E
authors.initials: E
authors.lastname: Grabbe
mesh_terms: D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D001783:Blood Flow Velocity / Q000502:physiology; D003287:Contrast Media; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography; D008833:Microcirculation / Q000473:pathology; D008955:Models, Cardiovascular; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA