定量CT骨密度测量预测椎体压缩强度的实验研究

Experimental Study of Predicting Vertebral Body Compressive Strength Using Quantitative Computed Tomography

笔者对３２个椎体用ＳｉｅｍｅｎｓＳｏｍａｔｏｍＨＩＱＣＴ机做了三种不同扫描方法的定量测量，并用材料测试机做了椎体单轴压缩负荷试验。通过对三种ＱＣＴ测量所得ＢＭＤ值与椎体压强的相关回归性研究证实三种方法所测的ＢＭＤ值（ｍｇ－ＣａＨａ／ｍｌ）与椎体的压强（Ｎ／ｃｍ２）均呈正比，相关性显著（Ｐ＜０．０１），其中椎体中部１０ｍｍ层厚单层扫描所测ＢＭＤ值与椎体压强的回归效果最好（Ｒ２＝０．６０４），椎体压强与ＢＭＤ值间存在平方回归关系，其最佳方程为γ＝２２２．５２．３５４χ＋０．０１７χ２。笔者认为ＱＣＴＢＭＤ测量作为一种非创伤性的方法，以其高度的敏感性和准确性，可以预测椎体的压缩强度，从而达到预测椎体的压缩性骨折，其中以椎体中部１０ｍｍ层厚单层扫描对椎体压缩强度的预测最敏感。

Total thirty-two vertebrae were scanned with three separate mothods and the compressive loads was performed using a material-testing machine.Vertebral compressive strength (VCS) is correlated at a hith level of significane(P<0.01) with three separate QCT measurement and the best regrssive effect is observed between the 10mm single section midplane stratgy and VCS (R2=0.604),and the VCS is related to the square of the bone mineral density with the equation:y=222.15-2.354×+0.017X2.These results further indicate that QCT as a non-invasive method with highly accuracy and sensitivity can provide an excellent predictor of the risk of vertebral compressive fracture.The central mearement of vertebral bone mineral density made with QCT is extremely sensitive for predicting VCS.