A Protocol for the Isolation of Carotid and Vertebral Arteries in MR Angiography

MR angiography [1- 9] is rapidly becoming a technique to evaluate blood flow in the carotid and vertebral arteries. We have been using a time-of-flight pulse sequence [9] to acquire axial images of carotid and vertebral arteries with flow-en-coded information. These axial images can be reformatted through a computer algorithm to give multiple angle presen-tations of the collected data in sagittal or coronal planes. We found that many of the reconstructed images were difficult to interpret because of overlap of right and left ver-tebral and carotid arteries (Fig. 1). Presented here is a protocol for optimizing the information obtained in the time-of-flight images. All of the angiograms were obtained on a clinical 1.5-T system. * Studies of the carotid artery bifurcations were per-formed with the standard linear head coil, which was used fo