角膜的生物力学特性显示出异构性,并且与近视眼中的轴长相对应
Lingfeng Chen1, Yangyi Huang2,3,4,5, Xiaoyu Zhang2,3,4,5
1College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China.
Investigative ophthalmology & visual science
|July 21, 2023
概括
在近视眼中,角膜的生物力学特性随着轴长度 (AL) 的增加而减弱. 这项研究发现,较长眼睛的触角模量和应力-应变指数 (SSI) 降低,突出显示AL.
科学领域:
- 眼科医生 眼科 眼科
- 生物医学工程 生物医学工程
- 角质科学 角质科学
背景情况:
- 近视眼经常表现出改变的生物机械性质.
- 了解这些变化对于折射手术的结果至关重要.
研究的目的:
- 为了研究近视眼中的角膜的ex vivo和in vivo生物力学特征.
- 为了将角膜生物力学与轴长 (AL) 相对应.
主要方法:
- 使用双轴拉伸系统,对近视眼中的51个角膜 stromal 镜片进行了ex vivo 测试.
- 对应力-张力曲线的分析,以确定材料特性.
- 在体内使用手术前压力-应变指数 (SSI) 参数进行体内评估.
主要成果:
- 触角模量和SSI随着AL (≥26毫米) 的增加显著下降.
- 与AL一起,角膜异质性增加.
- 在较短的眼睛 (<26毫米) 中,SSI与AL呈负相关性.
结论:
- 角质生物力学特性随着轴长度的增加而减少.
- 触角模量在水平方向较垂直方向较低.
- 轴长是准确的角膜生物力学参数计算的关键因素.
相关概念视频
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
296
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
296
Eccentric Axial Loading in a Plane of Symmetry
231
Eccentric axial loading occurs when an axial load is applied away from the centroidal axis of a structural member. This scenario is common in engineering, where structural elements may not be directly aligned due to various design or functional requirements.
231
Focusing of Light in the Eye
2.9K
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
2.9K


