A dynamic micro-CT scanner based on a carbon nanotube field emission x-ray source

Area of Science:

• Medical Imaging
• Biomedical Engineering
• X-ray Technology

Background:

• In vivo micro-CT imaging of small animals is challenging due to rapid, non-periodic physiological motion.
• Existing commercial micro-CT scanners struggle with the temporal resolution required for free-breathing subjects.

Purpose of the Study:

• To develop and evaluate a prototype physiologically gated micro-CT scanner.
• To achieve high-resolution, synchronized imaging of small animal respiratory motion.

Main Methods:

• Utilized a carbon nanotube field emission micro-focus x-ray source for synchronized pulsing.
• Implemented physiological gating to synchronize imaging with animal respiratory signals.
• Evaluated system performance using phantoms and anesthetized mice.

Main Results:

• Achieved prospective respiratory-gated micro-CT imaging of anesthetized, free-breathing mice.
• Demonstrated a temporal resolution of 50 ms.
• Obtained a spatial resolution of 6.2 lp mm(-1) at 10% system MTF.

Conclusions:

• The prototype scanner overcomes limitations of current micro-CT systems for in vivo small animal imaging.
• High spatial and temporal resolutions enable detailed imaging of free-breathing small animals.
• The technology is well-suited for studying physiological processes in real-time.