3D Simultaneous Post-Contrast T1/T2 Mapping and Synthetic Multi-Contrast Late Gadolinium Enhancement at 0.55T:...

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Biomedical Engineering

Background:

• Comprehensive myocardial tissue characterization is crucial for diagnosing and managing cardiac conditions.
• Current imaging techniques often require multiple scans, increasing complexity and scan time.
• Standardized, efficient methods for whole-heart assessment are needed.

Purpose of the Study:

• To develop and validate a simplified 3D simultaneous post-contrast parametric mapping and synthetic late gadolinium enhancement (LGE) imaging technique.
• To enable comprehensive whole-heart myocardial tissue characterization at 0.55T.
• To compare the performance of the proposed 3D method against conventional 2D sequences.

Main Methods:

• A 3D joint T1/T2 mapping sequence with interleaved inversion recovery (IR) and T2 preparation was utilized.
• Intrinsically co-registered 3D T1, T2, and proton density maps were generated using dictionary matching.
• Bloch equation-based models generated multi-contrast 3D synthetic LGE images (IR-LGE, T2IR-LGE).
• In vivo evaluation was performed on 10 porcine myocardial infarction models.

Main Results:

• 3D T1/T2 maps showed findings consistent with 2D references, accurately reflecting changes in myocardial infarction scar tissue.
• Significantly decreased post-contrast T1 and increased T2 values were observed in scar regions compared to remote myocardium (P<0.01).
• Generated 3D synthetic LGE images demonstrated excellent contrast, with improved scar-to-myocardium contrast for bright-blood IR-LGE and improved scar-to-blood/myocardium contrast for gray-blood IR-LGE.

Conclusions:

• The proposed 3D method provides comprehensive myocardial tissue characterization in a single, simplified scan.
• Imaging findings are consistent with established 2D reference sequences.
• This technique shows significant promise for efficient and complete cardiac assessment.