CAROTID-ARTERY STENOSIS, OCCLUSION, AND PSEUDO-OCCLUSION - FIRST-PASS, GADOLINIUM-ENHANCED, 3-DIMENSIONAL MR-ANGIOGRAPHY - PRELIMINARY-STUDY

PURPOSE: To determine the accuracy of gadolinium-enhanced three-dimens ional magnetic resonance (MR) angiography in the evaluation of carotid artery stenosis. MATERIALS AND METHODS: A prospective blinded compari son of first-pass MR angiography with conventional digital subtraction angiography (DSA) was performed in 21 patients suspected of having ca rotid artery stenosis. MR angiography was performed on a 1.5-T magnet with gradient overdrive equipment, with a coronal radio-frequency-spoi led, three-dimensional, fast low-angle shot sequence after intravenous injection of contrast material. The guidelines of the North America S ymptomatic Carotid Endarterectomy Trial for measuring stenosis of the internal carotid artery were applied on maximum intensity projection i mages and conventional angiograms. RESULTS: Grading of stenoses at MR angiography agreed with that at DSA in 92% of the 44 carotid arteries. In the 18 carotid arteries with severe stenosis (70%-99%), agreement was 94%. All internal carotid occlusions (n=7) or pseudo-occlusions (n =3) were accurately detected with MR angiography. CONCLUSION: The accu racy of gadolinium-enhanced MR angiography in characterizing the degre e of carotid stenosis was high. Findings with MR angiography were accu rate for differentiating between occlusion and pseudo-occlusion.