正常绝经后女性椎体骨密度测量——2000QCT与QCT3000的对照研究

The Comparative Study of Measurement of Vertebral Body Bone Density in Normal Postmenopause Women with 2000QCT and 3000QCT

目的通过比较两种定量CT（QCT）体模对本地区正常绝经后女性椎体骨矿密度（BMD）的测量,探讨QCT体模对BMD测量的影响。资料与方法分别采用2000QCT与QCT3000两种体模及相同的扫描参数,对绝经后1-27年（平均15年）的正常受检者116人行T12-L2椎体QCT骨密度测定。（1）通过配对t检验比较两种QCT体模测量的椎体BMD值、T值、Z值的统计学差异,并分别计算出95%的可信区间作为正常值的参考;（2）对两种QCT体模椎体的BMD值、T值、Z值按年龄进行分组,通过单因素方差分析分别比较两体模各组椎体的BMD值、T值、Z值,并通过SNK法进行组间两两比较。结果2000QCT体模BMD值、Z值的均值明显高于QCT3000,而T值的均值则0.05）。结论QCT体模及其软件系统对QCT测量结果有较大的影响,同时其他许多因素对QCT测量也存在影响,当使用其结果对骨质疏松症（OP）进行诊断和治疗时,要结合当地该人群及该体模的正常值标准进行综合分析。

Objective To explore the influence factor of QCT phantoms in measuring BMD through comparing two kinds of QCT phantoms that used to measure local normal post-menopause women＇s vertebra of bone mineral density （BMD）. Materials and Methods The bone density of T12 - L2 with QCT was measured for 116 female members in local old age university after their menopause 1 - 27 years using phantoms of 2000 QCT and QCT 3000 with same scanning parameter respectively. （ 1 ） The statistical difference of vertebral BMD value T value and Z value between two phantoms through pairing t test was compared, and the 95 percent confidence interval respectively as the reference of normal value was also calculated. （2） Groups of the two phantoms＇ vertebral BMD value T value and Z value according to age was divided, and the vertebral BMD value T value and Z value respectively through single factor variance analyzing and the inter-group difference through SNK was also compared. Results The BMD value and mean value of Z of 2000QCT＇ s phantom was much higher than that of QCT3000, but the mean value of T was lower than that of QCT 3000 （ P 〈 0.01 ） . The inter-group statistics showed： The older of the age the BMD and T value of the two vertebral phantoms were gradually lower. It had significant statistics meaning among the three groups （ P 〈 0.01 ）. Z value among the three groups had no significant statistics meaning （ P 〉 0.05 ）. Conclusion The QCT phantom and soft ware system ＂affect the results of the QCT measuring obviously and other factors also affect the results. When using the result to diagnose and treat osteoporosis, we should analyze the results combining the local people and the phantom＇s normal value.