Abstract:
:We determined whether the accuracy of magnetic resonance angiography (MRA) in the peripheral run-off vessels can be improved by using contrast-enhanced (CE) three-dimensional (3D) technique in comparison to electrocardiograph (ECG)-triggered two-dimensional (2D) time-of-flight (TOF) technique. In a prospective study 20 patients with occlusions of the pelvic and/or femoral arteries underwent a CE 3D MRA (repetition time (TR): 5 ms, (TE) echo time: 2 ms, flip angle (FA): 30 degrees ) and an ECG-triggered 2D time-of-flight (TOF) technique (TR: 408 resp. 608 ms, TE: 7 ms, FA: 70 degrees) of the run-off vessels on a 1.5 T MR system. Each patient received a contrast material volume of 0.15 mmol/kg of body weight of gadolinium (Gd)/DTPA using an automatic injector. The tube system to the patient was flushed by 50 mL of a saline solution applied with the same injection rate as the contrast material administration. The start of the 3D MR sequence was tailored individually to the applied contrast material after determination of circulation times by a prior bolus. All patients underwent each conventional or digital arteriography for comparison, as well. The visualization of the run-off vessels was ranked on a scale of 0-3 (0 = poor, 1 = fair, 2 = good, 3 = excellent) by three blinded reviewers. They also graded the vascular segments as either occluded or significantly altered (>50% reduction in diameter) or free of significant stenosis. CE 3D MRA was significantly faster in imaging the run-off vessels in comparison to the ECG-triggered 2D TOF technique. All 160 vascular segments were visualized with the 3D method, whereas only 142/160 segments were seen with 2D technique. The resulting image quality ranking of all vascular segments was significantly higher (p < 0.05) using CE 3D MRA (2.8) than with the 2D TOF technique (2.4). The detection of the stenoses was possible with both techniques. The grading of seven of seven stenoses was correct with 3D method and in five of seven cases with the 2D TOF technique. All vessel occlusions were detected by using both techniques. Small collaterals were visualized in more detail with the CE 3D MR angiography. These data demonstrate an improvement in image quality and accuracy of MRA of the peripheral arteries using a CE 3D technique in comparison to an ECG-triggered 2D TOF sequence.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Vosshenrich R,Kopka L,Castillo E,Böttcher U,Graessner J,Grabbe Edoi
10.1016/s0730-725x(98)00078-2subject
Has Abstractpub_date
1998-10-01 00:00:00pages
887-92issue
8eissn
0730-725Xissn
1873-5894pii
S0730-725X(98)00078-2journal_volume
16pub_type
杂志文章abstract:BACKGROUND AND PURPOSE:Slice-encoding metal artifact corrections (SEMAC)-view-angle tilting (VAT) sequences have recently been used in clinical protocols to reduce metal artifacts in MR scans of patients with spinal instrumentation. The objective of this study was to compare the SEMAC-VAT sequence with the conventional...
journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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pub_type: 杂志文章
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更新日期:1998-01-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:1988-07-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:1998-11-01 00:00:00
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更新日期:1997-01-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/j.mri.2012.10.010
更新日期:2013-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:1987-01-01 00:00:00
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更新日期:1996-01-01 00:00:00
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更新日期:2004-04-01 00:00:00
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更新日期:2005-02-01 00:00:00
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更新日期:2013-01-01 00:00:00
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更新日期:2003-07-01 00:00:00
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journal_title:Magnetic resonance imaging
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