XECT--a least squares curve fitting program for generalized radiotracer clearance model.

Area of Science:

• Biomedical Engineering
• Medical Physics
• Computational Biology

Background:

• Accurate quantification of radiotracer kinetics is crucial for diagnostic and research applications.
• External detection of radiotracer decay requires sophisticated modeling to interpret tissue activity.
• Non-monoexponential decay models are often necessary for complex biological systems.

Purpose of the Study:

• To develop and present a computational program for fitting generalized, non-monoexponential models of radiotracer decay.
• To enable the calculation of optimal model parameters, including blood flow rate.
• To provide a tool for visualizing experimental data against fitted model curves.

Main Methods:

• Utilizes a joint Monte Carlo-Simplex algorithm for parameter estimation.
• Applies the algorithm to fit externally detected decay of radiotracer activity in tissue.
• Generates tabular and graphical outputs of experimental data and model fits.

Main Results:

• Successfully calculates optimal parameters for generalized, non-monoexponential decay models.
• Determines the rate of blood flow from the fitted model parameters.
• Provides a clear visual comparison between experimental data and the fitted curve.

Conclusions:

• The developed program offers a robust method for analyzing radiotracer kinetics.
• The joint Monte Carlo-Simplex algorithm provides accurate parameter estimation for complex decay models.
• This tool aids in the quantitative analysis of radiotracer studies in biological tissues.