Nyquist ghost correction of breast diffusion weighted imaging using referenceless methods.

Area of Science:

• Magnetic Resonance Imaging
• Medical Physics
• Biomedical Engineering

Background:

• Nyquist ghosts in single-shot spin-echo echo-planar imaging (EPI) are problematic in breast diffusion-weighted imaging (DWI).
• Standard 3-line navigator correction often fails due to factors like incomplete fat suppression and B0 inhomogeneity.
• Effective ghost reduction is crucial for accurate breast DWI interpretation.

Purpose of the Study:

• To compare the efficacy of the standard 3-line navigator with four data-driven referenceless methods for Nyquist ghost correction in breast DWI.
• To evaluate novel and existing referenceless techniques for improved ghost mitigation.

Main Methods:

• Breast DWI data from 41 patients acquired using SS SE-EPI were retrospectively analyzed.
• Raw data were corrected using the standard 3-line navigator and four referenceless methods.
• Ghost levels were quantified by background signal intensity and analyzed using a linear mixed model.

Main Results:

• All four referenceless methods demonstrated statistically significant superior performance over the standard 3-line navigator.
• This improved ghost correction was consistent across all tested b-values (0, 100, 600, and 800 s/mm²).

Conclusions:

• Referenceless methods provide a robust and effective solution for reducing Nyquist ghosts in breast DWI.
• These techniques eliminate the need for additional calibration scans, simplifying the imaging protocol.