High resolution in vivo micro-CT with flat panel detector based on amorphous silicon.

Area of Science:

• Biomedical imaging
• Medical physics
• Small animal research

Background:

• Accurate anatomical information is crucial for interpreting functional imaging data in small animal models.
• Integrating micro-computed tomography (micro-CT) with fluorescence molecular tomography (FMT) can improve the precision of molecular imaging.
• Existing micro-CT systems may have limitations in resolution or speed for certain preclinical applications.

Purpose of the Study:

• To construct and evaluate a high-resolution in vivo micro-CT system for small animal imaging.
• To assess the system's capability for providing anatomical information to complement FMT.
• To demonstrate the feasibility of the developed micro-CT system for in vivo applications.

Main Methods:

• A fast-scanning micro-CT system was designed using an amorphous silicon flat panel detector (FPD) and a micro-focus x-ray tube.
• Image reconstruction was performed using the Feldkamp algorithm accelerated by a graphics processing unit (GPU).
• System performance was evaluated using phantoms to determine spatial resolution, beam hardening artifacts, and contrast-to-noise ratio (CNR).

Main Results:

• The micro-CT system achieved a spatial resolution of 13 line pairs per millimeter (lp/mm) at a 6 cm field of view with a magnification factor of 4.
• Beam hardening artifacts were minimal in transaxial images of a water phantom after correction.
• The contrast-to-noise ratio (CNR) was assessed using various tissue phantoms, and successful in vivo imaging of an anesthetized mouse was demonstrated.

Conclusions:

• The developed high-resolution in vivo micro-CT system is suitable for small animal imaging.
• The system provides high-quality anatomical data that can serve as reconstruction priors for FMT.
• This integrated imaging approach holds promise for advancing preclinical molecular imaging research.