Robust water fat separated dual-echo MRI by phase-sensitive reconstruction.

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Imaging Analysis

Background:

• Accurate water-fat separation is crucial for quantitative MRI analysis.
• Existing Dixon methods can be susceptible to artifacts, limiting their robustness.

Purpose of the Study:

• To develop and evaluate a robust water-fat separation method for T1-weighted symmetric two-point Dixon data.
• To assess the performance of the phase-sensitive reconstruction (PSR) method in challenging imaging conditions.

Main Methods:

• Introduced phase-sensitive reconstruction (PSR) for water-fat separation.
• PSR involves tissue voxel cluster identification, phase unwrapping via Poisson's equation, and sign correction.
• Evaluated robustness by quantifying water-fat swap artifacts in 733 image volumes and comparing with commercial software.

Main Results:

• The PSR method showed high robustness, with minimal phase unwrapping failures and misclassifications.
• Observed artifacts were localized and did not spread, even in the presence of motion or susceptibility variations.
• PSR exhibited fewer water-fat swap artifacts compared to commercial software.

Conclusions:

• The PSR method reliably produces water-fat separated whole-body images from symmetric two-echo spoiled gradient echo data.
• PSR performs robustly under both ideal conditions and in the presence of common imaging artifacts.
• This method enhances the reliability of quantitative MRI analysis by improving water-fat separation accuracy.