DEDICATED HEAD-NECK COIL IN MR-ANGIOGRAPHY OF THE SUPRAAORTIC ARTERIES FROM THE AORTIC-ARCH TO THE CIRCLE OF WILLIS

Purpose. To evaluate the usefulness of a dedicated head-neck coil in p re operative imaging of the supra-aortic arteries. Material and Method s: Forty consecutive patients with suspected carotid ar tery stenosis underwent MR angiography (MRA). Using a dedicated head-neck coil, we m ade a complete evaluation of the supra-aortic arteries and graded the internal carotid artery (ICA) stenoses. MRA was performed at 1.5 T wit h: coronal 3D FISP from the aortic arch to the circle of Willis; trans verse 2D FLASH and 3D TONE of the carotid bifurcation; transverse 3D T ONE of the carotid siphon and the circle of Willis; and transverse 3D FISP of the aortic arch. I.a. digital subtraction angiography (DSA) wa s used as the reference. ICA stenoses of 70% and more at DSA (NASCET m ethodology) were regarded as severe. Results. Severe ICA stenoses were detected with high sensitivity and specificity: 93% and 92% respectiv ely for coronal 3D FISP; 90% and 85% respectively for transverse 2D FL ASH; and 97% and 94% respectively for transverse 3D TONE. The carotid siphon and the intracranial ICA were best depicted by 3D TONE. None of the applied sequences gave a satisfactory visualization of the aortic arch or of the origins of the vertebral arteries. Conclusion: With th e head-neck coil, the supra-aortic arteries (including the intracrania l vessels) were visualized without the need to reposition the patient, but depiction of the aortic arch was not acceptable. The quantificati on of ICA stenoses was reliable.