A dialyzer-based flow system for validating dynamic contrast enhanced MR image acquisition.

Area of Science:

• Medical Imaging
• Biomedical Engineering

Background:

• Dynamic contrast enhanced MRI (DCE-MRI) is sensitive for mass characterization and therapy response assessment.
• DCE-MRI faces challenges in standardization and procedural reproducibility.
• Evaluating the reproducibility of DCE-MRI under active flow conditions is crucial.

Purpose of the Study:

• To describe a simple dialyzer-based flow system for evaluating DCE-MRI reproducibility.
• To assess the precision and variability of contrast agent kinetics in DCE-MRI.
• To establish a method for short-term reproducibility testing of rate constants.

Main Methods:

• Utilized a dialyzer-based flow system with a bolus injection of Gd-DTPA.
• Analyzed MR signal to determine contrast agent kinetics and washout rate constants.
• Employed a simple model for estimating Gd-DTPA washout rate constants through polysulfone tubules.

Main Results:

• The flow phantom yielded reproducible measurements of washout rate constants.
• Washout rates showed a consistent increase from 0.20 ± 0.005 min⁻¹ to 0.25 ± 0.008 min⁻¹ over 32 weeks.
• Dynamic CT measurements at week 24 were approximately 12% higher than corresponding MRI values.

Conclusions:

• A simple dialyzer-based flow phantom is effective for testing DCE-MRI pulse sequences.
• This system facilitates short-term reproducibility testing of rate constants in DCE-MRI.
• The findings support the use of this phantom for enhancing DCE-MRI standardization.