Vessel-encoded dynamic magnetic resonance angiography using arterial spin labeling

Area of Science:

• Medical Imaging
• Radiology
• Neuroimaging

Background:

• Noninvasive angiography is crucial for diagnosing cerebrovascular diseases.
• Current methods like Time-of-Flight (TOF) angiography have limitations in selectivity and invasiveness.
• Need for advanced MRI techniques for detailed vessel visualization.

Purpose of the Study:

• To introduce and evaluate a new noninvasive MRI method for vessel-selective angiography of cerebral arteries.
• To assess the technique's ability to generate individual angiograms for specific carotid and vertebral arteries.
• To compare the efficacy of different pulse train durations for optimal vessel visibility.

Main Methods:

• Developed a technique combining vessel-encoded pseudocontinuous arterial spin labeling (PCASL) with 2D dynamic angiographic readout.
• Acquired data using a 3-T MRI scanner in healthy volunteers.
• Performed selective labeling at the neck for internal carotid and vertebral arteries; reconstructed using Bayesian inference.

Main Results:

• The vessel-selective dynamic angiograms were consistent with TOF images.
• A longer PCASL pulse train duration (1000 ms) improved distal vessel visibility.
• The technique provided rapid, noninvasive, and selective angiograms.

Conclusions:

• The presented noninvasive MRI method enables vessel-selective angiography of cerebral arteries.
• This technique shows promise as a noninvasive alternative to intra-arterial angiography for major vessels.
• Optimized pulse train duration enhances visualization of smaller, distal vessels.