Assessing indocyanine green pharmacokinetics in mouse liver with a dynamic diffuse fluorescence tomography system

Area of Science:

• Biomedical Imaging
• Pharmacokinetics
• Medical Physics

Background:

• Tissue pharmacokinetic rates offer quantitative physiological and pathological insights for organ function assessment.
• Dynamic diffuse fluorescence tomography (DFT) requires high sensitivity and anatomical priors to extract pharmacokinetic rates from temporal boundary intensity data.

Purpose of the Study:

• To investigate the pharmacokinetics of indocyanine green (ICG) in mouse liver.
• To evaluate the synergistic application of dynamic DFT and X-ray computed tomography (XCT) for quantitative liver function assessment.

Main Methods:

• A sensitive dynamic DFT system with photon-counting channels was employed in a CT-scanning mode.
• X-ray computed tomography (XCT) provided a priori anatomical information for enhanced reconstruction quality.
• Pharmacokinetic rates were extracted from reconstructed ICG concentration-time curves using a 2-compartment model and the Gauss-Newton fitting scheme.

Main Results:

• In vivo experiments in 10 healthy mice yielded ICG uptake and excretion rates in the liver.
• The obtained rates provide a quantitative measure for evaluating liver function.
• The study validated the effectiveness of the combined imaging system and pharmacokinetic analysis method.

Conclusions:

• The synergistic dynamic DFT and XCT approach enables accurate pharmacokinetic rate extraction for liver function evaluation.
• This method offers a non-invasive, quantitative tool for assessing organ function in vivo.
• The findings support the clinical potential of advanced fluorescence tomography techniques.