结合Micro‑CT成像和超声共振谱技术的环状皮质骨弹性性质研究  

Study on elastic properties of annular cortical bone using Micro‑CT imaging and ultrasonic resonance spectroscopy

作　　者：王蕊 樊璠[1] 沈飞[1] 王月 任鹏玲 王振常 牛海军[1] Wang Rui;Fan Fan;Shen Fei;Wang Yue;Ren Pengling;Wang Zhenchang;Niu Haijun(School of Biological and Medical Engineering,Beihang University,Beijing 100191,China;Imaging Center,Beijing Friendship Hospital Affiliated to Capital Medical University,Beijing Institute of Clinical Medicine,Precision and Intelligent Imaging Laboratory,Beijing 100050,China)

机构地区：[1]北京航空航天大学生物与医学工程学院,北京100191 [2]首都医科大学附属北京友谊医院影像中心,北京市临床医学研究所精准与智慧影像实验室,北京100050

出　　处：《数字医学与健康》2023年第2期90-95,共6页DIGITAL MEDICINE AND HEALTH

基　　金：国家自然科学基金项目(32071315);国家重点研发计划(2020YFC0122201)。

摘　　要：目的探究Micro‑CT成像和超声共振谱技术相结合进行非规则环状皮质骨样本弹性性质测量的可行性。方法取5月龄新西兰大白兔胫骨中段,切割出3块环状皮质骨样本。使用Micro‑CT扫描样本并重建出三维形状,建立有限元模型,计算理论共振频率;同时使用超声共振平台对样本进行扫频测量,获得共振频谱,从中提取出实验共振频率;使用基于差分进化的全局寻优算法,调整有限元模型中的弹性常数值,最小化理论与实验共振频率之间的差距,并计算弹性模量、泊松比(v)等工程模量。结果使用最优弹性常数计算出的理论共振频率与实验值相吻合,首次获得了兔皮质骨材料在横观各向同性下的全部独立弹性常数:c_(11)=(23.16±1.70)GPa、c_(33)=(34.59±0.53)GPa、c_(44)=(7.91±0.96)GPa、c_(66)=(5.29±0.61)GPa、c_(_(13))=(11.26±0.71)GPa,由此计算出的工程模量为:E_(1)=(15.38±1.59)GPa,E_(3)=(27.42±1.76)GPa,G_(13)=(7.91±0.96)GPa,v_(12)=0.456±0.042,v_(13)=0.177±0.015。结论结合Micro‑CT成像和超声共振谱技术可有效测量环状皮质骨样本的弹性性质,该方法降低了小尺寸皮质骨样本的制备难度,能够获得更全面的弹性性质。Objective To explore the feasibility of Micro‑CT imaging combined with ultrasonic resonance spectroscopy to measure the elastic properties of irregular tubeshaped cortical bone samples.Methods Three tubeshaped cortical bone samples were extracted from the middle tibia of 5‑month‑old New Zealand white rabbits.Using Micro‑CT to scan the sample and reconstruct the three‑dimensional geometry,the finite element model was established and the theoretical resonant frequencies were calculated.At the same time,the ultrasound resonance platform was used to measure the sample′s resonant spectrum,and extract the experimental resonant frequencies.The global optimization algorithm based on differential evolution was used to adjust the elastic constants in the finite element model,minimize the differences between the theoretical and experimental resonant frequencies.The elastic moduli,Poisson′s ratio and other engineering moduli were then calculated from the optimized elastic constants.Results The theoretical resonant frequencies calculated by using the optimal elastic constant was consistent with the experimental value.All the independent elastic constants of rabbit cortical bone material under transverse isotropy elasticity assumptions were obtained for the first time:c_(11)=(23.16±1.70)GPa,c_(33)=(34.59±0.53)GPa,c_(44)=(7.91±0.96)GPa,c_(66)=(5.29±0.61)GPa,c_(13)=(11.26±0.71)GPa,the engineering moduli calculated from these constants were:E_(1)=(15.38±1.59)GPa,E_(3)=(27.42±1.76)GPa,G_(13)=(7.91±0.96)GPa,v_(12)=0.456±0.042,v_(13)=0.177±0.015.Conclusion The elastic properties of tube‑shaped cortical bone samples can be measured effectively by using Micro‑CT and ultrasound resonant spectroscopy.This method reduces the difficulty in preparing small size cortical bone samples and more comprehensive elastic properties can be obtained.

关 键 词：Micro‑CT 超声共振谱 有限元 弹性常数 小尺寸皮质骨 

分 类 号：R445.1[医药卫生—影像医学与核医学]