3D magnetization-prepared rapid gradient echo with a RF saturation band on a compact 3T scanner

Area of Science:

• Medical Imaging
• Radiology
• Magnetic Resonance Imaging (MRI)

Background:

• Flow-related ghost artifacts in 3D MPRAGE MRI are caused by unsaturated arterial flow.
• These artifacts are more pronounced on compact 3T (C3T) scanners with smaller radiofrequency (RF) transmit coils.
• The smaller RF coil leads to a rapid B1 field fall-off, exacerbating artifacts, particularly in younger patients.

Purpose of the Study:

• To suppress flow-related artifacts in 3D MPRAGE scans on C3T scanners.
• To investigate the efficacy of adding radiofrequency saturation band (RFSB) pulses to the 3D MPRAGE sequence.

Main Methods:

• RFSB pulses were integrated as a preparation pulse option into the 3D MPRAGE sequence.
• 37 subjects were scanned on a C3T scanner with and without RFSB; 10 underwent repeat scans for reliability.
• Neuroradiologists evaluated image quality, artifacts, and diagnostic confidence; quantitative analysis assessed image intensity variability and test-retest differences.

Main Results:

• RFSB significantly reduced artifacts and improved diagnostic confidence in the posterior fossa (p < 0.0001).
• Test-retest analysis showed RFSB reduced image intensity variability in the cerebellum (normalized difference decreased from 8.71% to 6.41%, p = 0.0059).
• The method demonstrated broader applicability on a whole-body 3T scanner with a T/R head coil.

Conclusions:

• Integrating RFSB pulses into 3D MPRAGE effectively reduces flow-related ghost artifacts on C3T scanners.
• The method enhances image quality and diagnostic confidence, suggesting potential for widespread implementation across MRI systems with smaller RF-transmit coils.