Second-Order Motion-Compensated Echo-Planar Cardiac Diffusion-Weighted MRI: Usefulness of Compressed Sensitivity...

Area of Science:

• Cardiovascular Imaging
• Magnetic Resonance Imaging
• Diffusion-Weighted Imaging

Background:

• Cardiac diffusion-weighted imaging (DWI) using second-order motion-compensated spin echo (M2C) offers noninvasive in-vivo microstructural assessment.
• However, M2C DWI is limited by a relatively low signal-to-noise ratio (SNR).
• Echo-planar imaging (EPI) with compressed sensitivity encoding (EPICS) presents a potential solution to enhance SNR.

Purpose of the Study:

• To combine M2C DWI with EPICS (M2C EPICS DWI).
• To compare the image quality of M2C EPICS DWI against standard M2C DWI.

Main Methods:

• Prospective study involving ex-vivo hearts, healthy volunteers, and patients with various heart diseases.
• Utilized 3-Tesla MRI scanners with M2C EPICS DWI and M2C DWI sequences.
• Image quality assessed using apparent SNR (aSNR) and subjective ratings by three observers on a 5-point Likert scale.

Main Results:

• M2C EPICS DWI demonstrated significantly higher aSNR than M2C DWI in healthy volunteers across multiple resolutions.
• In patients with diseased hearts, M2C EPICS DWI also showed significantly higher aSNR compared to M2C DWI.
• Apparent diffusion coefficient (ADC) values were higher with M2C EPICS DWI, and over 80% of subjective ratings favored M2C EPICS DWI in in-vivo hearts.

Conclusions:

• Cardiac imaging using M2C EPICS DWI shows improved overall image quality.
• M2C EPICS DWI offers a higher aSNR compared to conventional M2C DWI.
• This technique holds promise for enhanced noninvasive cardiac microstructural assessment.