PC HYPR flow: a technique for rapid imaging of contrast dynamics

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging
• Angiography

Background:

• Improving spatial and temporal resolution in 3D contrast-enhanced (CE) time-resolved MR angiography is crucial for accurate diagnosis.
• Current methods face limitations in achieving high resolution and signal-to-noise ratio (SNR) simultaneously.

Purpose of the Study:

• To introduce and evaluate a novel hybrid phase contrast (PC) and CE MRA acquisition with HYPR reconstruction (PC HYPR Flow).
• The goal is to enhance spatial and temporal resolution and SNR in 3D radial CE time-resolved MR angiography.

Main Methods:

• PC HYPR Flow integrates a CE exam with a subsequent PC scan to guide HYPR reconstruction of time-series data.
• Feasibility was assessed through computer simulations, healthy subjects, patients with brain arteriovenous malformations, and a canine aneurysm model.

Main Results:

• Simulations showed preserved contrast agent dynamics and superior performance for 2D acceleration.
• In vivo studies demonstrated 3D time series with a 0.5s frame rate, improved spatial resolution (0.8 mm isotropic), and enhanced arterial/venous ratio.
• The method maintained temporal waveform fidelity and high SNR.

Conclusions:

• PC HYPR Flow offers simultaneous 3D isotropic sub-millimeter spatial resolution, sub-second temporal reconstruction, and high SNR.
• This technique shows promise for various CE MRA applications, potentially improving diagnostic capabilities.