Three-dimensional arterial spin labeling imaging with a DANTE preparation pulse

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging
• Physiology

Background:

• Arterial spin-labeled (ASL) imaging can exhibit bright intravascular signal artifacts.
• Vascular suppression (VS) techniques aim to reduce these artifacts by dephasing labeled spins.
• Current VS methods like Motion-Sensitized Driven-Equilibrium (MSDE) can reduce signal uniformity and increase echo time.

Purpose of the Study:

• To compare the efficacy of Delays Alternating with Nutation for Tailored Excitation (DANTE) preparation pulses for VS in ASL imaging against the MSDE technique.
• To evaluate the impact of DANTE-prepared ASL on signal intensity distribution and artifact reduction.

Main Methods:

• ASL imaging was performed using both DANTE-prepared and MSDE VS sequences.
• Studies were conducted on a flow phantom with moving water and on human volunteers.
• Signal intensity, signal decay patterns, and inter-hemispheric differences were analyzed.

Main Results:

• Both DANTE and MSDE reduced bright intravascular signal artifacts in volunteer ASL images.
• Phantom studies showed similar signal decay patterns for moving water between the two methods.
• DANTE-prepared ASL demonstrated smaller right-left signal intensity differences compared to MSDE.

Conclusions:

• DANTE-prepared ASL effectively suppresses vascular signals while preserving signal intensity uniformity.
• DANTE offers a promising alternative for vessel suppression in ASL imaging, potentially improving image quality.
• This method addresses limitations of existing VS techniques in ASL MRI.