Contrast-enhanced, three-dimensional MR angiography of the carotid artery at 1.0 tesla in comparison to intra-arterial DSA - Is the method suitable for diagnosis of carotid artery disease?

Purpose: To evaluate the efficacy of three-dimensional, contrast-enhanced magnetic resonance angiography (CE-MRA) of the carotid artery with a 1.0 T system in comparison to intra-arterial conventional angiography (i.a.CA) for the assessment of carotid artery disease. Method: 55 patients with suspected stenosis of the carotid artery were examined with a 3D-CE gradient-echo sequence on a 1.0T scanner (TR/TE=6.2/2.2ms) and a selective DSA i.a. angiography. Image quality was evaluated by estimating the arterial contrast and venous enhancement. Morphological pathologies were registered for all arteries, stenoses of the internal carotid artery were graded by applying the NASCET criteria. Results: Sensitivity and specificity of MRA in detecting high-grade stenosis (greater than or equal to 70%) and occlusion of the extracranial internal carotid artery were 97.7 and 94.0%. Therapeutic relevant misinterpretations were mostly based on overestimating the stenoses. Conclusion: The applied CE-MRA technique with a 1.0 T system is suitable for the assessment of carotid artery stenoses. In case of a therapeutically relevant stenosis revealed by MRA, however, verification of the diagnosis by i.a.CA is recommended.