Purpose:To determine the diagnostic performance of contrast-enhanced MR angiography (CE-MRA) with four doses of gadobenate dimeglumine for detection of significant steno-occlusive disease of the carotid, renal, and pelvic vasculature.
Materials and Methods:Eighty-four patients with suspected disease of the renal (n ϭ 16), pelvic (n ϭ 41), or carotid (n ϭ 27) arteries underwent CE-MRA (3D-spoiled gradient-echo sequences) at 1.5T. CE-MRA was performed with gadobenate dimeglumine at 0.025, 0.05, 0.1, or 0.2 mmol/kg (23,24,19, and 18 patients, respectively) administered at 2 mL/sec. Accuracy, sensitivity, specificity, and positive and negative predictive values (PPV and NPV, respectively) for detection of significant disease (Ͼ50% stenosis or occlusion for renal/pelvic arteries; Ͼ70% stenosis or occlusion for carotid arteries) was determined by three fully blinded, independent radiologists using conventional digital subtraction angiography (DSA) as reference standard. All comparisons were tested statistically (ANOVA, chi-square, and Mantel-Haenszel tests as appropriate) and reader agreement (kappa) was assessed.Results: Values for accuracy, sensitivity, specificity, PPV, and NPV on CE-MRA were consistently higher for 0.1 mmol/kg gadobenate dimeglumine (accuracy ϭ 95.2-97.3%, sensitivity ϭ 84.2% (all readers), specificity ϭ 96.9 -99.2%, PPV ϭ 80.0 -94.1%, NPV ϭ 97.6 -97.7%). The greater accuracy of the 0.1 mmol/kg dose was significant (P Ͻ 0.01, all readers) compared to all other dose groups. Agreement between the three readers was good for all dose groups (kappa Ն0.58), with the highest percent agreement (85.7%) noted for the 0.1 mmol/kg dose.
Conclusion:Significantly better diagnostic performance on CE-MRA of the renal, pelvic, and carotid arteries is achieved with a gadobenate dimeglumine dose of 0.1 mmol/kg bodyweight.