人与猪角膜的生物力学特性之比较

目的：由于人角膜很难获取，因此在角膜研究中，猪角膜经常被用做人角膜的替代模型。因为人们认为，它与人角膜最为相似，本文的研究目的是比较两者在生物力学上的异同之处。方法：切成条状的人角膜和猪角膜在INSTRON万能实验机上做单轴拉伸实验，测量它们的强度、应力-应变、应力松弛。结果：人角膜和猪角膜的强度，应力-应变性质相差不大，但在同一伸长比下，猪角膜的应力松弛比人角膜大，结论：仅考虑强度、应力-应变关系，猪角膜可作为人角膜的代用品进行研究，但若考虑应力松弛等生物力学特性，则人角膜与猪角膜存在的较大差异。因此，采用猪角膜作为人角膜力学研究的动物模型是不适合的。

BIOMECHANICAL PROPERTIES OF HUMAN AND PORCINE CORNEA

Due to difficulty in obtaining human cornea, pigs are often adopted as substitute models for cornea research because they are considered to have eyes similar to humans. The purpose of this study is to understand the similarities and difference in the biomechanical properties between human cornea and porcine cornea. 20 human cornea specimens and 30 porcine specimens were used for uniaxial test by Instron apparatus. Their tensile strength, stress strain relationship, relaxation properties were tested. The tensile strength and stress strain relation were very similar in the two kinds of specimens while significant differences were observed in the stress relaxation relationship: under the comparable stress and elongation level, porcine cornea relaxed much more significantly than human cornea. If tensile strength and stress strain were the only mechanical factor to be investigated, porcine cornea could be used as a substitute model for human cornea research. However, when stress relaxation factors were concerned, the biomechanical properties were quite different in the two species. In conclusion, porcine cornea cannot be used as a model for human corneas in mechanical property studies.