Biomechanics of corneal ectasia and biomechanical treatments.
Biomechanics of corneal ectasia and biomechanical treatments.
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DOI：
10.1016/j.jcrs.2014.04.013
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发表时间：
2014-06
影响因子：
2.8
通讯作者：
Dupps WJ Jr
中科院分区：
文献类型：
--
作者：
Roberts CJ;Dupps WJ Jr
存在许多用于角膜的局部/断层摄影检测的算法，所述角膜具有屈光手术后扩张的风险。提出难以找到基于角膜形态学特征的通用筛查工具的原因是曲率、高度和厚度变化都是圆锥角膜和屈光手术后扩张的次要体征，并且主要异常是生物力学特性。它进一步提出，生物力学的修改是集中在性质上，而不是一个统一的广义弱化，并在弹性模量的焦点减少沉淀的生物力学失代偿的周期，这是由不对称的生物力学性能。这引发了应变增加、应力重新分布以及随后的焦点变陡和变薄的重复循环。各种干预措施被描述的生物力学失代偿的这个周期是如何中断，如基质角膜环段，重新分配角膜应力，和胶原交联，修改的基本结构特性。
Many algorithms exist for the topographic/tomographic detection of corneas at risk for post-refractive surgery ectasia. It is proposed that the reason for the difficulty to find a universal screening tool based on corneal morphologic features is that curvature, elevation, and pachymetric changes are all secondary signs of keratoconus and post-refractive surgery ectasia and that the primary abnormality is in the biomechanical properties. It is further proposed that the biomechanical modification is focal in nature, rather than a uniform generalized weakening, and that the focal reduction in elastic modulus precipitates a cycle of biomechanical decompensation that is driven by asymmetry in the biomechanical properties. This initiates a repeating cycle of increased strain, stress redistribution, and subsequent focal steepening and thinning. Various interventions are described in terms of how this cycle of biomechanical decompensation is interrupted, such as intrastromal corneal ring segments, which redistribute the corneal stress, and collagen crosslinking, which modifies the basic structural properties.