Estimating optical parameters of biological tissues with photon-counting micro-CT

Area of Science:

• Biomedical Optics
• Medical Imaging Physics
• Translational Research

Background:

• Optical properties of biological tissues are crucial for fluorescence photon transport and optical molecular tomography resolution.
• Current methods for estimating these optical parameters, especially for small animal imaging, are complex, ill-posed optimization problems.
• Accurate optical parameter estimation is vital for advancing molecular imaging techniques.

Purpose of the Study:

• To develop and validate a novel approach for estimating optical parameters of biological tissues using photon-counting micro-computed tomography (micro-CT).
• To overcome the limitations of traditional methods in small animal imaging by providing a more robust parameter estimation technique.
• To enable accurate mapping of optical parameter distributions in vivo.

Main Methods:

• Utilized photon-counting x-ray data from multi-energy micro-CT to reconstruct images.
• Performed multi-organ segmentation and material decomposition based on tissue constituents.
• Calculated optical absorption and scattering coefficients from the derived tissue composition.
• Validated the approach through numerical simulations, phantom experiments, and in vivo animal studies.

Main Results:

• The proposed method successfully estimated optical parameters of biological tissues.
• Achieved a relative error of less than 10% in optical parameter estimation.
• Demonstrated accurate mapping of optical parameter distributions in small animal models.
• Successfully correlated tissue constituents derived from micro-CT with optical properties.

Conclusions:

• The novel micro-CT-based approach provides an accurate and efficient method for estimating optical parameters in biological tissues.
• This technique offers significant potential for improving the accuracy and reliability of optical molecular tomography in small animal research.
• The findings pave the way for enhanced in vivo molecular imaging and diagnostics.