Brain diffusion MRI with multiplexed sensitivity encoding for reduced distortion in a pediatric patient population

Area of Science:

• Radiology
• Medical Imaging
• Neuroimaging

Background:

• Diffusion-weighted imaging (DWI) is crucial for pediatric brain assessment.
• Standard single-shot echo-planar imaging (ssEPI) DWI sequences suffer from geometric distortions and T2*-blurring.
• Novel techniques are needed to improve DWI quality in children.

Purpose of the Study:

• To evaluate the benefits of multiplexed sensitivity-encoding (MUSE) and reversed polarity gradients MUSE (RPG-MUSE) for pediatric brain DWI.
• To compare image quality and geometric fidelity of MUSE and RPG-MUSE against conventional ssEPI.

Main Methods:

• Retrospective analysis of DWI in 14 pediatric patients.
• Comparison of ssEPI, MUSE, and RPG-MUSE sequences.
• Quantitative assessment of geometric distortions using Dice Coefficient and Hausdorff Distance.
• Evaluation of apparent diffusion coefficient (ADC) values and qualitative image quality grading.

Main Results:

• MUSE and RPG-MUSE demonstrated significantly lower geometric distortions than ssEPI.
• RPG-MUSE was rated higher for overall image quality and lower for distortions compared to ssEPI and MUSE.
• No significant differences in ADC values were found across the methods.

Conclusions:

• MUSE and RPG-MUSE provide superior geometric accuracy in pediatric brain DWI.
• RPG-MUSE enhances both image quality and geometric fidelity over ssEPI.
• These advanced DWI techniques improve diagnostic potential for pediatric neuroimaging.