Scanning time efficient slinky for non-contrast MRA at low field

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging
• Radiology

Background:

• Slab boundary artifacts (SBAs) degrade the quality of non-contrast multi-slab 3D time-of-flight magnetic resonance angiography (3D TOF MRA).
• The previously developed SLINKY (Sliding Interleaved kY) acquisition suppresses SBAs without flow assumptions and maintains signal-to-noise ratio (SNR) comparable to MOTSA.
• However, the original SLINKY method requires navigator echoes for phase error correction, increasing imaging time.

Purpose of the Study:

• To introduce an improved SLINKY technique that eliminates the need for navigator echoes.
• To reduce imaging time for 3D TOF MRA while maintaining SBA suppression and SNR.
• To demonstrate the efficacy of a specifically designed radiofrequency (RF) pulse in correcting phase errors without navigator echoes.

Main Methods:

• Implementation of a novel SLINKY acquisition strategy utilizing a specifically designed RF pulse.
• Avoidance of navigator echo collection for phase error correction along the kY axis.
• Acquisition of interleaved kY-axis data with a continuously moving slab along the z-axis.

Main Results:

• The improved SLINKY technique successfully corrects phase errors without navigator echoes.
• Slab boundary artifacts are effectively suppressed, similar to the original SLINKY method.
• No significant ghosting or SNR reduction was observed in the reconstructed images compared to the navigator-echo-based method.

Conclusions:

• The improved SLINKY technique offers an efficient alternative for 3D TOF MRA by reducing scan time.
• This method preserves image quality and artifact suppression capabilities without compromising SNR.
• The use of a specialized RF pulse is key to avoiding navigator echoes and enhancing workflow in MRA.