科维斯ST参数的表现,包括更新的压力-应变指数,以区分正常,Forme-Fruste,亚临床和临床眼之间
Yuan-Yuan Miao1, Xiao-Min Ma2, Zhan-Xin Qu1
1National Clinical Research Center for Ocular Diseases, Eye Hospital, WenZhou Medical University (Y.-Y.M., Z.-X.Q., B.-W.W., H.X., P.W., X.-B.Z., J.-J.W., Y.-F.Y., S.-H.C., F.-J.B), Wenzhou, Zhejiang, China.
American journal of ophthalmology
|October 25, 2023
概括
更新的压力-应变指数 (SSIv2) 能够有效地区分正常眼睛与角膜及其各个阶段. 其他参数如IIR,ARTh和CBI也显示了诊断能力.
科学领域:
- 眼科医生 眼科 眼科
- 生物机械工程 生物机械工程
- 角膜成像 角膜成像
背景情况:
- 角膜是一种渐进的角膜脱落,影响视力敏度.
- 准确的诊断和分期对于及时干预至关重要.
- 科尔维斯ST提供角膜的生物力学评估.
研究的目的:
- 评估更新的应力-应变指数 (SSIv2) 和其他Corvis ST参数的诊断性能.
- 为了区分正常的眼睛和不同阶段的角质 (FFKC,SKC,CKC-I,CKC-II,CKC-III).
- 将SSIv2的准确性与其他已建立的生物力学指数进行比较.
主要方法:
- 总共分析了1084只眼睛,分为正常和不同阶段的角质.
- 进行Corvis ST检查以获得生物力学参数,包括SSIv2,CCT和bIOP.
- 用接收器操作特征 (ROC) 曲线分析来评估诊断准确性.
主要成果:
- 在正常眼睛中,SSIv2和ARTh显著更高,而IIR和CBI在正常眼睛中显著更低.
- 在SSIv2,ARTh,IIR,CBI和角质严重程度之间发现了显著的相关性.
- SSIv2在曲线下的面积 (AUC) 显示出最高的区别,以区分正常眼睛和眼睛.
结论:
- 更新的压力-应变指数 (SSIv2) 显示出在区分正常角膜与角质的优越能力.
- 此外,SSIv2还有效地区分了角的不同阶段.
- IIR,ARTh和CBI表现出类似的,虽然不那么明显的诊断性能.
相关概念视频
01:18Transformation of Plane Stress
233
Studying stress transformation is essential in understanding how stress components within a material, like a cube under plane stress, change with rotation. This change is analyzed by considering a prismatic element within the cube. As the element rotates, the stress components acting on it—both normal and shearing stresses—change in magnitude and orientation. This change is quantified using trigonometric functions of the rotation angle, relating the forces acting on the rotated element's...
233
01:15Stress: General Loading Conditions
319
To grasp the intricacy of real-world conditions where multiple loads are applied simultaneously to a structure, one might visualize a section passing through a specific point within a body, aligned parallel to the xy plane. This section is subjected to various forces, including original loads, normal forces, and shearing forces.
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
319
01:24Stress Concentrations
336
Stress concentration is when stress intensifies near discontinuities such as holes or abrupt cross-sectional changes in a structural member. This localized stress can often surpass the average stress within the member. The stress distribution in flat bars, either with a circular hole or varying widths connected by fillets, can be determined experimentally using a photoelastic method. The results are based on ratios of geometric parameters like the ratio of the hole's radius to the smaller...
336
01:23Stresses under Combined Loadings
156
When analyzing a bent tube with a circular cross-section subjected to multiple forces, it is crucial to determine the stress distribution in order to maintain structural integrity under varied load conditions.
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
156
01:20Normal Strain under Axial Loading
540
Normal strain under axial loading is an important concept in the field of mechanics of materials. Axial loading implies the application of a force along the axis of a material, like a column or bar. This force can either compress or stretch the material. In the context of axial loading, normal strain is the deformation experienced by the material in the direction of the loading force. It's calculated as the change in length divided by the original length of the material. This unitless ratio...
540
01:19Normal Stress
584
Normal stress is a type of stress that occurs when forces act perpendicular, or normal, to a material's cross-sectional area. This stress often arises in structures when subjected to axial loading, which is the application of force along the axis of an object. A practical example of this can be found in bridge truss members.
When a rod is under axial loading, the internal forces and corresponding stress are normal to the plane of the section, so it is termed normal stress. It's...
When a rod is under axial loading, the internal forces and corresponding stress are normal to the plane of the section, so it is termed normal stress. It's...
584