A study of volumetric visualization and quantitative evaluation of bone trabeculae in helical CT

Objectives: The aim of this study was to investigate the reliability of quantitative evaluation of bone trabeculae by helical CT. Methods: Ten specimens of human cadaver mandibular condyles were examined using both micro-CT and helical CT, and volume rendered three-dimensional (3D) images were obtained from the CT data. Micro-CT was used as the reference standard. From the micro-CT data images, bone trabeculae in each condyle were extracted by image processing and their volumes were calculated automatically. From the helical CT data images, the cortical bone was manually removed and bone trabeculae in each condyle were extracted using opacity curve and colour mapping thresholds. The optimal cut-off CT value that resulted in a similar volume of bone trabeculae obtained from helical CT and micro-CT data was investigated. Results: The optimal cut-off CT value to assess the volume of bone trabeculae accurately on 3D images obtained with helical CT data was found to be 200 Hounsfield units. Conclusions: This s...