3D PHASE-CONTRAST EPI MR-ANGIOGRAPHY OF THE CAROTID ARTERIES

Objective: Our goal was to compare 3D phase contrast (PC) echo planar imaging (EPI) MRA of the carotid and vertebral arteries with conventio nal 3D PC in volunteers and patients. Materials and Methods: The carot id arteries of 12 volunteers were imaged with conventional and EPI 3D PC sequences. The visibility for each of seven carotid and four verteb ral segments was qualitatively assessed. Signal intensity and homogene ity determinations were performed on the source images. Three patients with known carotid artery disease were also imaged with the same prot ocol. Results: EPI reduced 3D PC data acquisition time from 459 to 32 s (factor of 15). Both techniques permitted full assessment of the com mon carotid artery, the bifurcation, as well as the proximal internal carotid artery (ICA), external carotid artery (ECA), and vertebral art eries. Visualization of the distal ICA/ECA and vertebral arteries was inferior with EPI compared with the conventional acquisition. In all p atients, lesions as established by X-ray angiography were seen to equa l advantage with both techniques. Conclusion: EPI 3D PC MRA renders di agnostic images of the proximal carotid system. The considerable reduc tion in data acquisition time must be weighed against poorer image qua lity.