Efficient Interleaved Multi-Band Outer Volume Suppression for Highly Accelerated Simultaneous Multi-Slice Imaging of...

Area of Science:

• Magnetic Resonance Imaging
• Cardiovascular Imaging
• Pulse Sequence Design

Background:

• Simultaneous multi-slice (SMS) imaging accelerates cardiac MRI but can introduce artifacts.
• Outer volume suppression (OVS) is crucial for minimizing these artifacts, especially at high acceleration factors.

Purpose of the Study:

• To develop and evaluate novel multi-band outer volume suppression (MB-OVS) pulses for accelerated cardiac MRI.
• To assess the effectiveness of MB-OVS in reducing artifacts and improving image quality in SMS-accelerated CINE and perfusion scans.

Main Methods:

• MB-OVS pulses were designed by combining slab-selective saturation pulses.
• Pulse performance was evaluated using Bloch simulations and phantom experiments.
• In vivo cardiac CINE and perfusion scans were acquired with and without MB-OVS at high acceleration rates.

Main Results:

• Amplitude-optimized sinc pulses demonstrated optimal suppression efficiency, B1+ requirements, SAR, and slab profile.
• Cardiac CINE imaging with 5-fold SMS-OVS acceleration showed significantly reduced artifacts and maintained leakage-free quality.
• Perfusion imaging achieved 16-fold spatial-only acceleration with accurate contrast dynamics and no leakage artifacts.

Conclusions:

• Interleaved MB-OVS modules effectively suppress leakage artifacts in accelerated cardiac MRI.
• The proposed MB-OVS approach shows promise for further enhancing acceleration capabilities in cardiac imaging.