人眼角膜基质生物力学特性研究  

Biomechanical properties of normal human corneal stroma

作　　者：薛超[1] 向尧齐 王雁[1] 沈岷[2] 吴迪[1] XUE Chao;XIANG Yao-Qi;WANG Yan;SHEN Min;WU Di(From the Tianjin Eye Hospital,Tianjin Key Laboratory of Ophthalmology and Visual Science,Tianjin Eye Institute,Tianjin 300020,China;School of Mechanical Engineering,Tianjin University,Tianjin 300050,China)

机构地区：[1]天津市眼科医院,天津市眼科学与视觉科学重点实验室,天津市眼科研究所,天津市300020 [2]天津大学机械工程学院,天津市300050

出　　处：《眼科新进展》2019年第11期1009-1013,共5页Recent Advances in Ophthalmology

基　　金：国家自然科学基金资助项目(编号:81670884)~~

摘　　要：目的了解正常人眼角膜基质的生物力学特性,初步获得相对正常角膜组织生物力学相关参数。方法使用全飞秒激光小切口角膜基质透镜取出术术中获取的角膜基质透镜,根据实验需要裁切成角膜基质组织试件,在常温和水浴条件下,分别进行应力-应变实验、蠕变实验和应力松弛实验,初步得到新鲜角膜基质组织的应力-应变曲线、蠕变曲线和应力松弛曲线,以评估人眼角膜基质的生物力学特性。结果低应变区切线模量为(1.32±0.48)MPa,高应变区切线模量为(51.26±8.23)MPa,断裂点应变为(0.52±0.06)mm·mm-1,断裂点应力为(13.00±2.51)MPa。在应力为0.01 MPa、0.02 MPa、0.03 MPa时,角膜基质试件弹性模量分别为(0.89±0.25)MPa、(1.28±0.21)MPa、(1.69±0.18)MPa。在1.00 N恒定载荷下,角膜基质试件形变随时间延长而增大,早期变化较快,后期逐渐变缓,600 s时蠕变率为(4.57±1.67)%。维持角膜基质试件长度至初始长度的1.5倍,应力随着时间的延长逐渐衰减,早期衰减较快,随着时间的延长衰减趋于平缓,1 h时松弛率为(28.49±0.04)%。结论初步得出正常角膜基质组织的生物力学参数,可为进一步深入研究角膜的生物力学特性提供一定的理论参考。Objective To investigate biomechanical properties of normal human corneal stroma and obtain its biomechanical parameters preliminarily.Methods Corneal lenticule extracted from small incision lenticule extraction surgery were cut into specimens according to requirement.The stress-strain test,creep test and stress relaxation test were performed at room temperature in water bath,and then the stress-strain curve,creep curve and stress relaxation curve of relative fresh corneal stroma were obtained to evaluate the biomechanical properties of normal human corneal stroma.Results Low strain tangent modulus(LSTM)was(1.32±0.48)MPa,high strain tangent modulus(HSTM)was(51.26±8.23)MPa,strain and stress in fracture point(εD,σD)was(0.52±0.06)mm·mm^-1,(13.00±2.51)MPa,respectively.The elastic modulus of corneal stroma was(0.89±0.25)MPa,(1.28±0.21)MPa,(1.69±0.18)MPa,respectively at the stress of 0.01 MPa,0.02 MPa,0.03 MPa.At 1.00 N constant load,the deformation of the specimen enhanced with time,the change in early time was faster and gradually slowed down in the later period.The creep rate was(4.57±1.67)%at 600 s.Keeping the length of the corneal specimen 1.5 times as long as the initial length,the stress gradually attenuated with the extension of time,the early attenuation rate was relatively fast at the beginning and slowed down with time,and the relaxation rate was(28.49±0.04)%at 1 h.Conclusion The biomechanical characteristics of normal human corneal stroma are revealed in this study,which lay the foundation for the further research on human cornea.

关 键 词：角膜基质 生物力学特性 应力-应变实验 应力松弛实验 蠕变实验 

分 类 号：R778.1[医药卫生—眼科]