An oxygen-consuming phantom simulating perfused tissue to explore oxygen dynamics and (19)F MRI oximetry

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Physiology

Background:

• Accurate measurement of tissue oxygenation is critical for understanding and diagnosing various medical conditions.
• Fluorine-19 magnetic resonance imaging (19F MRI) oximetry offers a promising non-invasive method for assessing tissue oxygen levels.
• Validation of 19F MRI oximetry techniques requires reliable phantoms that accurately mimic physiological conditions.

Purpose of the Study:

• To present a reproducible phantom designed to simulate oxygen-consuming tissue.
• To enable the validation of 19F MRI oximetry techniques.
• To provide a platform for studying hypoxia in a controlled experimental setting.

Main Methods:

• Construction of a phantom using a haemodialysis filter with a gelatin matrix containing viable yeast cells.
• Incorporation of perfluorocarbon emulsions to mimic sequestered perfluorocarbons.
• Perfusion of a blood-substituting perfluorocarbon fluid through the filter fibers.
• Acquisition of 19F relaxometry MRI data using a 2D Look-Locker sequence on a 3T scanner.

Main Results:

• The phantom successfully simulated both acute and perfusion-related hypoxia.
• Spatially and temporally resolved imaging of simulated hypoxic conditions was achieved.
• Demonstrated the capability of the phantom to mimic oxygen consumption by cells.

Conclusions:

• The developed phantom serves as a valuable tool for validating 19F MRI oximetry.
• This experimental setup facilitates the simulation of oxygen consumption by somatic cells in vivo.
• It enables the validation of computational biophysical models for hypoxia assessment using 19F MRI.