A method for artifact correction due to demodulation phase errors in magnetic resonance imaging

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging (MRI)

Background:

• Quadrature demodulation in MRI is susceptible to phase errors in reference signals.
• These phase errors lead to image artifacts, degrading diagnostic quality.
• Existing hardware-based phase correction methods are often incomplete.

Purpose of the Study:

• To develop and validate a new method for correcting phase errors during MRI signal demodulation.
• To eliminate image artifacts resulting from inaccurate sinusoid and cosinusoid reference signals.
• To improve the overall quality and reliability of MRI images.

Main Methods:

• A reference scan is performed before the Fast Spin Echo (FSE) sequence, omitting frequency and phase encoding gradients.
• An echo train is acquired during the reference scan to capture phase errors.
• Phase errors of the demodulation reference signals (sinusoid and cosinusoid) are calculated for each echo.
• K-space data is corrected using the calculated phase errors to remove artifacts.

Main Results:

• The proposed reference scan method successfully calculated phase errors.
• Correction of k-space data effectively removed artifacts in the MRI images.
• Experimental results on a 0.35T MRI system demonstrated significant artifact reduction.
• The method proved effective in mitigating image distortions caused by phase errors.

Conclusions:

• The reference scan method offers an effective solution for correcting phase errors in MRI quadrature demodulation.
• This technique successfully removes image artifacts, enhancing MRI image fidelity.
• The proposed approach provides a valuable tool for improving MRI image quality without relying solely on hardware solutions.