【摘要】 目的 通过数字图像相关技术(digital image correlation, DIC)获取角膜变形位移场，并基于角膜边界位移数据反演其等效剪切模量，以期为角膜疾病的早期诊断与治疗提供支持，同时推动角膜力学特性研究的深入发展。方法 采用可视化角膜生物力学分析仪(corneal visualization scheimpflug technology, Corvis ST)获取喷气过程中角膜变形的一系列动态图像，利用DIC软件计算角膜平面位移场，进而反求表征其刚度属性的材料力学参数。结果 首先通过1组模拟数据对所提方法进行验证。结果显示，即使在高水平噪声扰动下，仍能精确求解出角膜的剪切模量。将该方法应用于7组正常角膜的实验测量数据，当以角膜水平和竖直两个方向的边界位移分量作为反问题的输入时，重建得到的等效剪切模量为(0.310±0.076) MPa;若仅考虑竖直边界位移分量时，则剪切模量为(0.286±0.063) MPa。结论 结合Corvis ST、DIC与材料参数类反演的新方法策略，在探索角膜生物力学特性表征方面展现出巨大的应用潜力，有助于推动在体、无损角膜测量技术的进一步发展。更多还原

【Abstract】 Objective To obtain the corneal deformation displacement field using digital image correlation(DIC) technology and to infer the equivalent shear modulus by utilizing the displacement data at the corneal boundary, thereby supporting the early diagnosis and treatment of corneal diseases and promoting the in-depth development of corneal mechanical property research. Methods A sequence of dynamic images depicting corneal deformation during the air puff process was captured using corneal visualization Scheimpflug technology(Corvis ST). The displacement field of the corneal plane was then calculated via DIC, and material stiffness parameters were extracted through inverse analysis. Results The proposed method was initially validated with simulated data, demonstrating that the shear modulus of the cornea could be accurately determined even under significant noise disturbances. The method was then applied to experimental measurement data from seven normal corneas. When both the horizontal and vertical components of the corneal boundary displacement were used as the input for the inverse problem, the reconstructed equivalent shear modulus was(0.310±0.076) MPa. When only the vertical component of the boundary displacement was considered, the shear modulus was(0.286±0.063) MPa. Conclusions The novel approach combining Corvis ST, DIC, and material parameter inversion demonstrates significant potential in characterizing the biomechanical properties of the cornea, contributing to the further advancement of in vivo, non-invasive corneal measurement techniques.更多还原