Performance Evaluation of a Prototype Micro-CT System

Small animal imaging is becoming an important screening tool for laboratory animals with transplanted diseases. Micro-computed tomography (micro-CT) is one of the most popular choices for small animal imaging because of its high spatial resolution and high signal-to-noise ratio. Recently, we have built a cone-beam micro-CT system based on a Faxitron micro-specimen radiographic system. The system consists of a microfocal X-ray source, a rotary stage with object holder, and a CsI-coupled CMOS detector. The presampling modulation transfer function (MTF) was measured and a geometric calibration procedure for this prototype system was performed. The projection data of mice were obtained and corrected based on the parameters obtained by geometric calibration procedure. Results of the studies show promising applicability to small animal imaging and also to investigating new image reconstruction algorithms.