Highly accelerated multi-shot intravoxel incoherent motion diffusion-weighted imaging in brain enabled by parametric...

Area of Science:

• Medical Imaging
• Radiology
• Neuroimaging

Background:

• Intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) is valuable for neurological and neurovascular diseases.
• Conventional single-shot DWI methods suffer from geometric distortion and poor image quality at high resolution.
• Multi-shot techniques like multiplexed sensitivity encoding (MUSE) improve quality but increase scan time, hindering routine use.

Purpose of the Study:

• To develop and validate an accelerated acquisition and reconstruction framework for four-shot IVIM DWI.
• To significantly reduce scan time while preserving or improving image quality and quantitative accuracy.
• To enable routine clinical application of high-quality multi-shot IVIM DWI.

Main Methods:

• Proposed a parametric-POCSMUSE framework to accelerate four-shot IVIM DWI by 70%.
• Acquired only one segment per b value (except b=0 and 600 s/mm²) for acceleration.
• Integrated an IVIM-estimation scheme for joint reconstruction of multi-b images from under-sampled data.

Main Results:

• Achieved a 70% scan time reduction (13 min 8 s to 4 min 8 s).
• Produced multi-b DW images with higher SNRs and lower reconstruction errors compared to conventional acceleration.
• Generated IVIM quantitative maps comparable in quality to fully sampled MUSE data.

Conclusions:

• The proposed parametric-POCSMUSE framework enables highly accelerated multi-shot IVIM DWI without sacrificing data quality.
• This method makes multi-shot IVIM DWI feasible for routine MRI examinations.
• Improved geometric fidelity and reduced scan time enhance clinical applicability.