Simultaneous static and cine nonenhanced MR angiography using radial sampling and highly constrained back projection...

Area of Science:

• Radiology
• Cardiovascular Imaging
• Medical Physics

Background:

• Peripheral arterial disease (PAD) diagnosis often relies on imaging techniques that may be invasive or lack dynamic information.
• Nonenhanced magnetic resonance angiography (NEMRA) offers a non-invasive alternative for visualizing the peripheral vasculature.

Purpose of the Study:

• To introduce and evaluate a novel pulse sequence for simultaneous static and cine NEMRA of peripheral arteries.
• To assess the feasibility of capturing both vascular anatomy and dynamic pulse wave propagation in a single scan.

Main Methods:

• A cine NEMRA pulse sequence was developed and tested on a 1.5 Tesla (T) system in 10 volunteers and 6 patients with PAD.
• The impact of multi-shot imaging and highly constrained back projection (HYPR) reconstruction on image quality and temporal resolution was investigated.
• Signal propagation rate along the arterial tree was quantified from the cine angiograms.

Main Results:

• The sequence successfully generated simultaneous static and cine images, displaying vascular anatomy and arterial pulse wave propagation.
• Multi-shot cine NEMRA enhanced temporal resolution and reduced artifacts.
• HYPR reconstruction significantly improved image quality for short temporal reconstruction footprints (P < 0.001).
• Slower pulse wave propagation was observed in patients with PAD compared to volunteers.

Conclusions:

• Simultaneous static and cine NEMRA of peripheral arteries is feasible and clinically applicable.
• Multi-shot acquisition and HYPR reconstruction are valuable techniques for enhancing arterial conspicuity and temporal resolution in NEMRA.
• This technique shows promise for improved non-invasive assessment of peripheral arterial hemodynamics and PAD.