摘要
目的探索胶原交联术后4周角膜基质弹性模量与基质深度的定量关系,为交联术前个性化手术设计和术后效果评估提供理论基础。方法选取健康7月龄新西兰白兔7只,任选1只做空白对照组,其余6只左眼行角膜交联术,为实验组,右眼作自身对照。术后4周,取眼球制作角膜基质冷冻切片,沿角膜基质深度方向选取3~4个50μm×50μm的区域进行原子力显微镜压痕实验,使用Sneddon接触模型对压痕曲线进行拟合,获得弹性模量,研究角膜基质弹性模量与基质深度的定量关系。结果胶原交联术后4周,角膜基质弹性模量是其自身对照眼弹性模量的1.59倍。实验组相对弹性模量(E)与基质深度(x)的关系为E=0.66+6.05 e(-x/77.50),拟合优度为0.97。有效的交联深度为190μm±41μm。结论胶原交联术后4周角膜基质的弹性模量随基质深度仍存在指数衰减的规律。本文方法可获得角膜的有效交联深度,为相关的实验提供参考。
Objective To explore the quantitative relationship between corneal matrix elastic modulus and matrix depth after collagen cross-linking operation,and to provide a theoretical basis for personalized surgical design before cross-linking operation and postoperative effect evaluation.Methods Seven healthy 7-month-old New Zealand white rabbits were selected.One was selected as the blank control group.The remaining 6 left eyes were subjected to corneal cross-linking as the experimental group,and the right eyes were used as self-control.Four weeks after the operation,the eyeballs were taken to make frozen sections of the corneal stroma.Three to four 50μm×50μm areas were selected along the depth of the corneal stroma for atomic force microscope indentation experiments.The Sneddon contact model was used to fit the indentation curve to obtain an elastic modulus.To study the quantitative relationship between corneal stroma elastic modulus and stroma depth.Results Four weeks after collagen cross-linking,the elastic modulus of the corneal stroma was 1.59 times the elastic modulus of its own control eye.The relationship between the relative elastic modulus(E)and the matrix depth(x)in the experimental group was E=0.66+6.05 e(-x/77.50),and the Goodness of fit was 0.97.The effective crosslinking depth was 190μm±41μm.Conclusions Four weeks after collagen cross-linking,the elastic modulus of the corneal stroma still has an exponential decay law with the depth of the stroma.This method can obtain the effective cross-linking depth of the cornea,and provide reference for related experiments.
作者
曾正
李林
张海霞
ZENG Zheng;LI Lin;ZHANG Haixia(School of Biomedical Engineering,Capital Medical University,Beijing Key Laboratory of Fundamental Researchon Biomechanics in Clinical Application,Beijing 100069)
出处
《北京生物医学工程》
2023年第3期221-226,共6页
Beijing Biomedical Engineering
基金
国家自然科学基金(31470914、31370952)资助。
关键词
胶原交联术
原子力显微镜
基质力学特性
Sneddon模型
定量关系
collagen cross-linking
atomic force microscopy
matrix mechanical properties
Sneddon model
quantitative relationship
