4D Dark Blood Arterial Wall Magnetic Resonance Imaging: Methodology and Demonstration in the Carotid Arteries

PURPOSE: To propose and test a four-dimensional (4D) dark-blood magnetic resonance imaging (MRI) method based on a radial sampling trajectory capable of displaying the human arterial wall and its motion in three spatial dimensions over the cardiac cycle. METHODS: The carotid arteries of volunteer and patient subjects were imaged with the proposed 4D dark-blood MRI sequence on a 3T scanner. Validation of arterial lumen and arterial wall areas obtained with the proposed 4D dark-blood technique was made with respect to established two-dimensional bright-blood cine and high spatial resolution three-dimensional dark-blood MRI protocols, respectively. RESULTS: The proposed 4D MRI method provided for dark-blood display of the carotid arterial wall and demonstrated its movement and distension over the cardiac cycle. Quantitative measurements of arterial lumen and wall areas were in statistical agreement with established MRI techniques. CONCLUSION: 4D blood suppressed MRI of the human vascular system with submillimeter isotropic spatial resolution is feasible in a clinically reasonable scan time, and data obtained in the carotid arteries show good agreement with established MRI techniques. Future efforts will examine the constellation of data provided by the method and investigate its utility for assessing cardiovascular risk.