Technical Note: A safe, cheap, and easy-to-use isotropic diffusion MRI phantom for clinical and multicenter studies

Area of Science:

• Medical Imaging
• Biophysics
• Materials Science

Background:

• Diffusion Weighted Imaging (DWI) acquisition and processing lack standardization, leading to variations in Apparent Diffusion Coefficient (ADC) measures.
• Quality assurance with standardized test objects (phantoms) is essential for consistent DWI across different MRI scanners.

Purpose of the Study:

• To present a novel, easy-to-use, and cost-effective diffusion phantom for clinical DWI quality assurance.
• To compare the new phantom with existing diffusion phantoms used in clinical settings.

Main Methods:

• Development of a diffusion phantom utilizing a polyvinylpyrrolidone (PVP) solution and a phantom holder.
• Acquisition of an Apparent Diffusion Coefficient (ADC) versus temperature calibration curve for the phantom.

Main Results:

• The phantom's ADC values (808-857 mm²/s) are comparable to those in brain tissue.
• ADC measurements demonstrated high reproducibility (intra-class correlation coefficient > 0.8).
• A temperature-dependent ADC calibration equation was established with a total uncertainty of ±1.7%.

Conclusions:

• The developed isotropic diffusion MRI phantom is user-friendly for clinical environments.
• It is cost-effective, reproducible, and contains no hazardous substances.
• The phantom facilitates standardized DWI quality assurance and reliable ADC measurements.