A combined fluorescence and microcomputed tomography system for small animal imaging

Area of Science:

• Biomedical Imaging
• Molecular Imaging
• Preclinical Research

Background:

• Fluorescence molecular tomography (FMT) is crucial for in vivo molecular studies in small animals.
• FMT is limited by low spatial resolution, necessitating complementary anatomical information.
• Simultaneous functional and morphological analysis is highly desired for comprehensive in vivo studies.

Purpose of the Study:

• To develop and validate a hybrid system integrating full-angle free-space FMT and X-ray micro-cone-beam computed tomography (micro-CBCT).
• To provide simultaneous acquisition of functional (fluorescence) and anatomical (CT) imaging data in small animals.
• To overcome the spatial resolution limitations of FMT by combining it with high-resolution micro-CBCT.

Main Methods:

• A hybrid prototype system combining FMT and micro-CBCT was designed and constructed.
• Synchronous acquisition of fluorescence and micro-CBCT projection data was performed to ensure consistent animal positioning.
• Tomographic reconstruction was achieved using normalized Born-based spatial regularization for FMT and Feldkamp-Davis-Kress for micro-CBCT.

Main Results:

• The integrated system successfully acquired synchronous fluorescence and micro-CBCT projection data.
• Intrinsically coregistered functional and anatomical images were reconstructed.
• Preliminary experimental results from phantoms and in vivo mouse studies demonstrated the system's accuracy and performance.

Conclusions:

• The hybrid FMT and micro-CBCT system offers a promising solution for simultaneous molecular and anatomical imaging in small animals.
• This integrated approach enhances the capabilities of in vivo molecular imaging by providing both functional and morphological insights.
• The validated system paves the way for more comprehensive preclinical research and disease process studies.