OBJECTIVE: To identify carotid plaques in patients with coronary disease and indication for surgical treatment. To evaluate the degree of stenosis of the internal carotid arteries using color Doppler ultrasound (CDU) and magnetic resonance angiography (MRA). To compare plaque ultrasound echogenicity with signal intensity in magnetic resonance imaging (MRI). To evaluate the quality of the images and inter-rater reliability of MRI analysis. MATERIALS AND METHODS: This was a prospective study of 50 patients. Imaging methods used included ultrasound, T1- and T2-weighted MRI sequences, both with black-blood (BB) and fat sat black-blood (FSBB) techniques, and 3D TOF (time-of-flight) MRA, with and without administration of paramagnetic contrast media. RESULTS: Out of a total of 100 arterial segments, 81% showed stenosis on ultrasound whereas in 72 plaques with type 4 echogenicity there was high signal intensity in MRI in 59.7% in T1-BB technique, 65.3% in T1-FSBB, 62.5% in T2-BB and 66.7% in T2-FSBB. In type 2 plaques we observed high signal intensity in 71.4% in T1-BB and T1-FSBB, 85.7% in T2-BB and 71.4% in T2-FSBB. In type 1 plaques there was high signal intensity in 50% on T1- and T2-weighted images. In 19 segments ultrasound was considered normal. The same segments showed high signal intensity in 47.4% in T1-BB, 57.9% in T1-FSBB, 52.6% in T2-BB and T2-FSBB when evaluated with MRI. CONCLUSION: A high incidence of carotid atherosclerosis was observed. There was borderline reproducibility in the association between the degree of stenosis observed by CDU and MRA. There was no correlation between the types of plaque echogenicity assessed by ultrasound and MR signal intensity changes. The quality of MR images was considered optimal on T1- and T2-weighted images, and good in 3D TOF (axial). The quality of MRA images was considered excellent. Optimal inter-rater reliability was observed, with a kappa index above 0.71.
Magnetic resonance imaging; Ultrasound; Carotid artery disease; Comparative study
