摘要
目的以羊脊椎骨的松质骨灰重密度为标准,比较CT能谱成像、定量CT(QCT)对骨密度(BMD)测量方法的准确性,探讨CT能谱成像对BMD测量的价值。方法采用CT能谱成像分别测定38个羊椎体松质骨的钙-水基物质对密度(ρCa-H2O),根据BMDGSI=ρCa-H2O×1 004/400,得出BMD值。然后使用QCT测定每一椎体骨松质的BMD值,并将两组测定值与羊椎骨骨松质煅烧后得出的灰重密度值比较,同时分析两种影像学方法测量BMD值与灰重密度的相关性。结果 QCT测量BMD均值(0.394±0.069)g/cm3,灰重密度均值(0.445±0.050)g/cm3,CT能谱成像测量均值(0.430±0.056)g/cm3。(1)采用扩展的t检验法,QCT测量均值与灰重密度均值差异有统计学意义,且QCT测量值小于灰重密度值(t=3.530,P<0.05),CT能谱成像测量均值更接近灰重密度均值,两者间差异无统计学意义(t=1.138,P>0.05),CT能谱成像与QCT BMD测量均值差异有统计学意义,且CT能谱测量均值大于QCT测量均值(t=2.392,P<0.05)。(2)QCT组与灰重密度比较采用Spearman等级相关分析,QCT组的BMD测量均值与灰重密度均值均呈线性正相关,并有统计学意义(rQCT-灰重密度=0.58,P<0.05);CT能谱成像组与灰重密度组比较采用Pearson积差相关分析,CT能谱成像和灰重密度均值均呈线性正相关,并有统计学意义(rGSI-灰重密度=0.45,P<0.05)。结论 CT能谱成像和QCT所得BMD值与灰重密度值变化趋势均一致。CT能谱成像在采用钙-水基物质对时,测量BMD较QCT更为准确,可作为一种新的BMD测量方法。
Objective To compare the accuracy of bone mineral density （BMD） measured by CT spectral imaging （Gemstone spectral imaging, GSI）, Quantitative computed tomography （QCT）, and investigate the value of BMD measurement by GSIwith a standard of bone ash density of sheep trabecular bone in vertebra.MethodsThe 38 sheep vertebrae were scanned by gemstone spectral imaging （GSI） model and QCT. Using the GSI viewer, the calcium-water concentration （ρCa-H2O） of trabecular bone were measured. Then, we got the BMD value according to the formula BMDGSI=ρCa-H2O×1 004/400. The bone ash density were done by incinerating the vertebrae which were decorticated. At the last, we compared the two groups of BMD values by CT spectral imaging and QCT with the bone ash density in accuracy and correlation.ResultsThe BMD value of QCT, bone ash and GSI were （0.394±0.069）, （0.445±0.050） and （0.430±0.056） g/cm3. By extendedt-test, the bone ash density and BMDGSI were higher than the BMD value of QCT （t values were 3.530 and 2.392,P〈0.05）, and there was no significant difference between BMD determined by GSI and the bone ash density （t=1.138,P〉0.05）. Bone ash density were linear correlative with BMDGSI and BMDQCT （rGSI-Bone ash density=0.45,P〈0.05;rQCT-Bone ash density=0.58,P〈0.05） by Pearson product moment correlation analysis and Spearman rank correlation analysis.ConclusionThe changes of BMD determined by the two different measurements were consistent with the changes of bone ash density. The spectral computed tomography of calcium-water concentration has a more accurate BMD value compared with QCT. Thus, the spectral computed tomography is a new and more accuracy way to measure BMD.
出处
《中华临床医师杂志（电子版）》
CAS
2015年第17期90-94,共5页
Chinese Journal of Clinicians(Electronic Edition)
