Diffusion processes modeling in magnetic resonance imaging

Area of Science:

• Magnetic Resonance Imaging
• Biomedical Engineering
• Radiology

Background:

• Diffusion-weighted imaging (DWI) is crucial for evaluating neoplastic processes.
• Quantitative parameters and quality assurance in DWI require robust monitoring methods.
• Understanding hindered and restricted diffusion models is key for accurate interpretation.

Purpose of the Study:

• To propose a physical phantom for monitoring quantitative parameters in DWI.
• To develop a tool for quality assurance in DWI measurements.
• To simulate hindered and restricted diffusion for phantom validation.

Main Methods:

• Utilized polyvinylpyrrolidone solutions to simulate hindered diffusion.
• Created siloxane-based water-in-oil emulsions to mimic restricted diffusion.
• Employed high T2 silicon oils and a 1.5T MRI scanner for phantom DWI acquisition.
• Assessed phantom with various fat suppression techniques and whole-body DWI.

Main Results:

• Developed a phantom with control substances yielding apparent diffusion coefficient (ADC) values from 2.29 to 0.28 mm²/s.
• Simulated ADC values demonstrated relevance to mono-exponential equations with a 0.91% mean relative difference.
• Phantom enabled assessment of ADC measurement accuracy and fat suppression effectiveness.

Conclusions:

• The developed phantom accurately assesses ADC measurements and fat suppression efficacy.
• Control substances serve as effective body markers for quality assurance in whole-body DWI.
• This phantom enhances the reliability of DWI in neoplastic process evaluation.