Contrast enhanced MR angiography in the assessment of relevant stenoses in occlusive disease of the pelvic and lower limb arteries: diagnostic value of a two-step examination protocol in comparison to conventional DSA

• Published in: European journal of radiology 2002-02, Vol.41 (2), p.153-160
• Main Authors: Winterer, Jan Thorsten, Schaefer, Oliver, Uhrmeister, Peter, Zimmermann-Paul, Gesine, Lehnhardt, Stefan, Altehoefer, C, Laubenberger, J
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Angiography; Angiography, Digital Subtraction; Arterial occlusive disease; Arterial Occlusive Diseases - diagnosis; Arteries; Arteriosclerosis; Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Comparative studies; Contrast agents intravenous; Contrast Media; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Extremities; Female; Femoral Artery - pathology; Humans; Iliac Artery - pathology; Image processing, computer assisted; Imaging sequences; Magnetic Resonance Angiography; Male; Medical sciences; Middle Aged; MR-angiography; Pelvis; Popliteal Artery - pathology; Prospective Studies; Prospective study; Sensitivity and Specificity; Vascular
• ISSN: 0720-048X; 1872-7727
• DOI: 10.1016/S0720-048X(01)00386-2

Introduction/ objectives: Contrast-enhanced MRA (ce-MRA) has been claimed by many authors as a replacement of conventional angiography evaluating peripheral arterial occlusive disease. However, reliable detection of relevant stenoses (>70%) has to be provided for planning vascular interventions. Only few data in the literature focuses on this crucial problem. The purpose of this study was to evaluate this topic using a two-step body-coil-based MRA protocol. Methods and patients: Forty three patients presenting with 82 stenoses ≥50% and 61 stenoses >70% on conventional catheter angiogram received fast Gadolinium-DTPA-enhanced high resolution 3D MR angiography at 1.5 T covering the pelvic and peripheral vascular tree in two examination steps using the body-coil. The data were evaluated double-blinded by three readers distinguishing moderate (50–70%) from severe stenoses (>70%). Results: Overall sensitivity/specificity/accuracy was 84/60/70% evaluating 143 segments. Specificity was rather poor in the iliac (58%) and crural (50%) region and moderate in the femoral and popliteal level (73%). The negative predictive value ranged between 78 and 91%. The grade of stenosis tend to be overestimated rather than underestimated in all levels with positive predictive values between 55 and 78%. Discussions and conclusions: Body-coil-based contrast-enhanced MRA has limited potential in distinguishing moderate from severe stenoses in peripheral occlusive disease. Overestimations are more common than underestimations. Both occur mainly in small-sized crural arteries but also in larger iliac arteries where vessel course in partition direction may cause inadequacy between voxel size and lumen diameter in severe stenosis.