TY - JOUR
T1 - Intraindividual comparison of high-spatial-resolution abdominal MR angiography at 1.5 T and 3.0 T
T2 - Initial experience
AU - Michaely, Henrik J.
AU - Kramer, Harald
AU - Dietrich, Olaf
AU - Nael, Kambiz
AU - Lodemann, Klaus Peter
AU - Reiser, Maximilian F.
AU - Schoenberg, Stefan O.
PY - 2007/9
Y1 - 2007/9
N2 - Purpose: To prospectively compare three-dimensional (3D) contrast material-enhanced abdominal magnetic resonance (MR) angiography at 1.5 and 3.0 T intraindividually in healthy volunteers. Materials and Methods: After institutional review board approval and informed consent were obtained, 15 healthy male volunteers (age range, 24-41 years) underwent one abdominal 3D contrast-enhanced MR angiographic examination each at 1.5 and 3.0 T in random order. Fast 3D gradient-echo sequence with parallel imaging acceleration factor of three was used for MR angiography; acquired spatial resolutions were 1 x 0.8 x 1 mm3 (imaging time, 19 seconds) at 1.5 T and 0.9 x 0.8 x 0.9 mm3 (imaging time, 18 seconds) at 3.0 T. With the latter, volume of the 3D slab was 8% larger. At 1.5 T, 20-mL bolus of gadobenate dimeglumine was delivered at 2 mL/sec; at 3.0 T, 15-mL bolus was delivered at 2.5 mL/sec. Two blinded radiologists rated image quality of aorta and proximal renal arteries in consensus with five-point scale (4 = very good, 0 = nondiagnostic) according to sequence and in direct intraindividual comparison. Visibility of proximal and segmental renal arteries was rated with three-point scale (3 = completely visible, 1 = nonvisible). Signal-to-noise ratio (SNR) was determined with phantoms. For statistical analysis of the SNRs, t tests were used. Results: All MR angiographic measurements were diagnostic. Median score for image quality at both field strengths was 4. Depiction of proximal renal arteries was rated 3 at both field strengths. The visibility of the distal renal arteries was better at 3.0 T (median score, 3) than at 1.5 T (median score, 2). With direct comparison, 3.0-T MR angiography was better in 14 of 15 cases; no field strength was preferred in the other case. Mean SNR was significantly (P < .001) higher at 3.0 T (17.8 ± 0.09 [standard deviation]) than at 1.5 T (11.9 ± 0.10). Conclusion: MR angiography at 3.0 T provided better vessel visibility and SNR than did that at 1.5 T, although voxel size and imaging time were reduced.
AB - Purpose: To prospectively compare three-dimensional (3D) contrast material-enhanced abdominal magnetic resonance (MR) angiography at 1.5 and 3.0 T intraindividually in healthy volunteers. Materials and Methods: After institutional review board approval and informed consent were obtained, 15 healthy male volunteers (age range, 24-41 years) underwent one abdominal 3D contrast-enhanced MR angiographic examination each at 1.5 and 3.0 T in random order. Fast 3D gradient-echo sequence with parallel imaging acceleration factor of three was used for MR angiography; acquired spatial resolutions were 1 x 0.8 x 1 mm3 (imaging time, 19 seconds) at 1.5 T and 0.9 x 0.8 x 0.9 mm3 (imaging time, 18 seconds) at 3.0 T. With the latter, volume of the 3D slab was 8% larger. At 1.5 T, 20-mL bolus of gadobenate dimeglumine was delivered at 2 mL/sec; at 3.0 T, 15-mL bolus was delivered at 2.5 mL/sec. Two blinded radiologists rated image quality of aorta and proximal renal arteries in consensus with five-point scale (4 = very good, 0 = nondiagnostic) according to sequence and in direct intraindividual comparison. Visibility of proximal and segmental renal arteries was rated with three-point scale (3 = completely visible, 1 = nonvisible). Signal-to-noise ratio (SNR) was determined with phantoms. For statistical analysis of the SNRs, t tests were used. Results: All MR angiographic measurements were diagnostic. Median score for image quality at both field strengths was 4. Depiction of proximal renal arteries was rated 3 at both field strengths. The visibility of the distal renal arteries was better at 3.0 T (median score, 3) than at 1.5 T (median score, 2). With direct comparison, 3.0-T MR angiography was better in 14 of 15 cases; no field strength was preferred in the other case. Mean SNR was significantly (P < .001) higher at 3.0 T (17.8 ± 0.09 [standard deviation]) than at 1.5 T (11.9 ± 0.10). Conclusion: MR angiography at 3.0 T provided better vessel visibility and SNR than did that at 1.5 T, although voxel size and imaging time were reduced.
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U2 - 10.1148/radiol.2443061647
DO - 10.1148/radiol.2443061647
M3 - Article
C2 - 17709837
AN - SCOPUS:34548091389
SN - 0033-8419
VL - 244
SP - 907
EP - 913
JO - Radiology
JF - Radiology
IS - 3
ER -