Time-efficient simultaneous fat and water cardiac cine imaging using spiral magnetic resonance imaging

Area of Science:

• Cardiovascular Magnetic Resonance Imaging
• Medical Imaging Physics

Background:

• Cardiac cine imaging is crucial for assessing cardiac dysfunction.
• Water and fat (W/F) separation in cardiovascular magnetic resonance (CMR) aids in distinguishing tissues.
• Conventional methods using multi-echo balanced steady-state free precession (bSSFP) can introduce artifacts and lower temporal resolution.

Purpose of the Study:

• To implement and evaluate a spoiled gradient echo (SPGR) sequence with a spiral trajectory for simultaneous W/F separated cine imaging.
• To compare the performance of the spiral SPGR sequence against Cartesian bSSFP sequences in terms of efficiency and image quality.

Main Methods:

• Three sequences were compared: Cartesian 2-TE bSSFP, Cartesian 3-TE bSSFP, and the proposed spiral SPGR sequence.
• Scans were performed on five volunteers at 1.5T with specific spatial resolution and field of view.
• Quantitative analysis included contrast-to-noise ratio (CNR) measurements alongside qualitative assessments.

Main Results:

• The spiral SPGR sequence demonstrated superior temporal efficiency and reduced artifacts compared to Cartesian bSSFP sequences.
• The 2-TE bSSFP sequence exhibited the highest artifact levels, including fat/water swaps.
• The spiral method achieved approximately 50% scan time reduction with similar spatial/temporal resolution and lower specific absorption rate (SAR), and improved blood-myocardium contrast (p≤0.05).

Conclusions:

• The spiral SPGR sequence offers a promising approach for simultaneous W/F separated cine imaging.
• This technique enhances diagnostic potential by shortening examination times and lowering SAR.
• The improved contrast-to-noise ratio further supports its clinical utility in cardiac imaging.