Multishot diffusion-weighted SPLICE PROPELLER MRI of the abdomen

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Physics
• Biomedical Engineering

Background:

• Single-shot diffusion-weighted echo-planar imaging (DW-EPI) MRI is prone to susceptibility artifacts.
• Multishot fast spin echo (FSE)-based diffusion-weighted PROPELLER (DW-PROPELLER) MRI aims to reduce these artifacts.
• Abdominal DW-PROPELLER is challenging due to large fields-of-view and respiratory motion, causing signal cancellation by violating Carr-Purcell-Meiboom-Gill (CPMG) conditions.

Purpose of the Study:

• To evaluate the feasibility of combining the SPLICE (split-echo acquisition of FSE signals) technique with PROPELLER for abdominal diffusion-weighted MRI.
• To assess the ability of DW-SPLICE-PROPELLER to mitigate non-CPMG artifacts caused by motion.
• To improve the quality and apparent diffusion coefficient (ADC) map homogeneity in abdominal DW-PROPELLER imaging.

Main Methods:

• The SPLICE technique was employed to separate spin echo and stimulated echo signals using imbalanced readout gradients and an extended acquisition window.
• Two signal families with coherent phase properties were acquired and reconstructed separately to avoid destructive phase interference.
• Phantom studies were conducted to validate signal phase properties under varying initial magnetization phases.

Main Results:

• The SPLICE technique effectively mitigates non-CPMG artifacts in FSE-based sequences.
• Combining SPLICE with PROPELLER (DW-SPLICE-PROPELLER) demonstrated feasibility for abdominal DW imaging.
• Significant improvements in DW image quality and ADC map homogeneity were observed.

Conclusions:

• DW-SPLICE-PROPELLER is a promising technique for abdominal diffusion-weighted MRI.
• This method effectively overcomes challenges posed by respiratory motion and large fields-of-view.
• The technique enhances image quality and ADC map reliability, offering an advantage over conventional DW-EPI.