Kalender W A, Klotz E, Suess C
Radiology. 1987 Aug;164(2):419-23. doi: 10.1148/radiology.164.2.3602380.
In the assessment of vertebral bone mineral density (BMD) with quantitative computed tomography, accuracy is limited by systematic errors caused by beam-hardening effects and unknown marrow and fat concentrations in trabecular bone. Reproducibility depends on precise repositioning of the patient, selection of the region of interest (ROI), and apparatus stability. In an integrated approach, these error sources were taken into account. Dual-energy methods are incorporated and tested to avoid systematic errors. Contour-detection algorithms for automated ROI determination that work reliably and offer improved reproducibility and efficiency are presented. A new design of reference phantom with solid tissue-equivalent materials provides calibration in BMD units and checks apparatus stability. Dual-energy methods are necessary to achieve accuracy of 5% or better. Automated ROI definition and reference phantom methods are mandatory for reproducibility of 2% or better.
在通过定量计算机断层扫描评估椎骨骨密度（BMD）时，准确性受到由束硬化效应以及小梁骨中未知的骨髓和脂肪浓度所引起的系统误差的限制。可重复性取决于患者的精确重新定位、感兴趣区域（ROI）的选择以及设备的稳定性。在一种综合方法中，考虑了这些误差来源。纳入并测试了双能方法以避免系统误差。提出了用于自动确定ROI的轮廓检测算法，该算法可靠工作并提供了更高的可重复性和效率。一种采用固体组织等效材料的新型参考体模设计可提供BMD单位的校准并检查设备稳定性。双能方法对于实现5%或更高的准确性是必要的。自动ROI定义和参考体模方法对于实现2%或更高的可重复性是必不可少的。
