A quantitative evaluation of multiple biokinetic models using an assembled water phantom: A feasibility study

Area of Science:

• Nuclear Medicine
• Biomedical Engineering
• Pharmacokinetics

Background:

• Commercial phantoms primarily serve imaging system surveys for quality assurance.
• Customized phantoms for multi-compartment biokinetic models are scarce due to calculation and verification complexities.
• Biokinetic models are crucial for understanding metabolic mechanisms and internal circulation.

Purpose of the Study:

• To assess the feasibility of quantitatively evaluating multiple biokinetic models.
• To establish the validity of different compartment models using a custom-built water phantom.
• To bridge the gap between theoretical biokinetic models and practical quantitative evaluation.

Main Methods:

• Assembled a water phantom with seven acrylic boxes of varying sizes, interconnected by hoses to simulate biokinetic models.
• Infused Technetium-99m labeled methylene diphosphonate (Tc-99m MDP) into the phantom and simulated biological removal using de-ionized water.
• Utilized an automatic infusion pump and gamma camera scanning for data acquisition, alongside MATLAB programming for theoretical predictions.

Main Results:

• Successfully simulated five distinct biokinetic models within the assembled water phantom.
• Quantitatively evaluated time-dependent radioactive concentrations, comparing experimental data with theoretical predictions.
• Identified agreements and disagreements between simulated and predicted model behaviors, providing insights into model validity.

Conclusions:

• The custom water phantom is a feasible tool for quantitatively evaluating biokinetic compartment models.
• The study demonstrates the potential for numerical verification of metabolic mechanisms and internal circulatory systems.
• This approach facilitates the advancement of biokinetic modeling in biomedical research.