CE-MRA of abdominal and peripheral vessels at 3.0 T – initial experiences

Purpose: Feasibility of contrast-enhanced MR-Angiography (CE-MRA) of abdominal and peripheral arteries.

Subjects and Methods: All examinations were performed at a 3.0 T Intera system (Philips, Best, Netherlands). Abdominal CD-MRA was performed in 15 subjects (13 male, 2 female, age 24 to 61 years) using different protocols: FOV 400mm, matrix 335×512. TR/TE/FA=3.2–5.4 ms/ 1.1–1.5 ms/15–25°, the applied SENSE-factor (sf) varied from sf 3 to sf 5, realising breathhol time between 8 and 18.5s. The volume of the injected Contrast Media (Gadopentate Dimeglumine/ Gadobutrol, Schering,Berlin, Germany) was reduced by 1/3 as compared for the standard dosage at 1.5 T (2/3* 0.4ml/kg bw, or 2/3* 0.2ml/kg bw respectively). MRA of peripheral vessels was performed in 19 subjects (9 male, 10 female, age 15 to 75 years). In 14 cases the table movement feature “mobitrak” was used with the subsequent protocol: TR/TE/FA=3.6 ms/1.3 ms/ 20°. FOV 375mm, matrix 272×512, true voxel size, 1.38×1.38×3.5mm, 3 to 4 stacks, time per stack 24s.

Results: a) Abdominal MRA: 13/15 examinations where of diagnostic quality, anatomical variants of the liver artery could be clearly demonstrated. In two patients with ascites a drop of signal intensity in the center of the FOV caused poor image quality. b) peripheral vessels. In all cases an exellent visalisation of the whole vessel tree was achieved. Conspicuity of stenosis and occlusions was comparable to DSA.

Conclusion: MRA of abdominal arteries is feasible at 3T with SENSE factor 3 and higher, turning the breathhold time down to 8s. Further refinement of the method seems to be necessary esp. in case of ascites. CE-MRA at 3T yields an excellent visualisation of peripheral vessels.