定量CT用于测量老年人股骨头骨密度性别差异和位置差异

Cancellous bone mineral density measurement of femoral head with different genders and position by quantitative CT

目的利用定量计算机断层扫描技术(quantitative computed tomography,QCT)测量股骨头不同层面的松质骨体积骨密度(volumetric bone mineral density,v BMD),研究其性别差异以及位置差异。方法回顾性研究344例受试者的股骨头松质骨的v BMD,其中男96例、女248例。利用QCT软件中"3D Spine Exam Analysis"软件分析模块将股骨头划分为上(靠近股骨颈上部皮质)、中(经股骨颈中心)、下(靠近股骨颈下部皮质)三个层面。测量者对受试者的双侧股骨头的不同层面进行测量,计算并记录平均值。结果股骨头各层松质骨v BMD的性别差异无统计学意义(P上=0.210,P中=0.106,P下=0.115);股骨头上、中、下三层松质骨v BMD的中位数分别为149.49、163.98、153.93 mg/cm^3,差异有统计学意义(P<0.001),且中层显著大于上层和下层(P上中=0.001,P中下=0.002)。结论利用QCT中"3D Spine Exam Analysis"软件分析模块对股骨头进行测量具有可重复性强的特点,为髋部骨质疏松诊疗提供了新方法。股骨头的中间层骨密度显著大于上、下两层,并且股骨头的松质骨骨密度无性别差异。

Objective To investigate whether there are gender and position difference in cancellous volumetric bone mineral density(vBMD)of femoral heads by "3D Spine Exam Analysis" module in quantitative computed tomography(QCT).Methods Totally 344 subjects were selected for this retrospective study,and there were 248 females and 96 males.The QCT data was transferred to the QCT analysis workstation.The femoral head was divided into 3 layers parallel to the long axis of the femoral neck by the "3D Spine Exam Analysis"module of QCT Pro software:upper layer(close to the upper part of the femoral neck),middle layer(through the center of the femoral neck)and lower layer(close to the lower part of the femoral neck).The different layers of the femoral head were measured and recorded.Results There was no statistically significant difference in cancellous vBMD of femoral head at different layers between different sex subjects(Pupper=0.210,Pmiddle=0.106,Plower=0.115).There were statistical differences between cancellous vBMD at three levels of the femoral head(149.49 mg/cm^3,163.98 mg/cm3,153.93 mg/cm3),and the cancellous bone density of middle layer was significantly higher than that in the upper and lower layers(P-value of Friedman test was<0.001,andthe pairwise comparisons P-value after proofreading was Pupper-middle=0.001,Pmiddle-lower=0.002).Conclusions The vBMD of femoral head measured by "3D Spine Exam Analysis" module in QCT Pro software shows good repeatability.It provides a new method for the diagnosis and treatment of hip osteoporosis.The vBMD of the middle layer of the femoral head is significantly greater than that of the upper and lower layers,and there is no gender difference in the cancellous vBMD of the femoral head.