Performance Evaluation of a Novel Preclinical Micro-CT System In Vitro and In Vivo

Purpose: With the advent of innovation in the preclinical studies, micro-CT provides optimized resolution by high-power X-ray output tube and flat-panel detector with ultra-short scanning time. The aim of this study was to evaluate the performance of a novel preclinical micro-CT with different parameters and protocols. Methods: Imaging quality was evaluated by micro-CT HA and wire phantom. The high power output X-ray tube provides tube voltage from 40 to 90 kV with tube current, 10 to 800 μA. The detector with 1536 × 1944 pixels was implemented by three different binning modes (1 × 1, 2 × 2 and 4 × 4). The GPU-based reconstruction was applied with Feldkamp’s algorithm. The maximum reconstruction volume was 1944 × 1944 × 4536 per scan. The phantom images were acquired by four modes with pixel sizes of 44.9, 22.5,15 and 9 μm. In the animal study, ovariectomy mice were imaged followed by analysis of bone mineral density (BMD) and BV/TV ratio (bone volume/total bone volume). Results: Linearity (R²) measured in all imaging settings were > 0.9 and was 0.99962 at setting of 0.2 mm Cu filter, 90 kV tube voltage and 556 μA tube current. The spatial resolution as measured by full width half-maximum amplitude (FWHM) was 24 µm in the mode ultra-high resolution. The bone analysis results show the operated cohort has high significant (p < 0.05), whereas the control cohort revealed insignificant either in the BMD. Conclusion: In summary, this novel micro-CT system demonstrated the flexible capability and high spatial resolution with ultra-short acquisition time, and a feasible quantitative BMD software.