摘要
目的利用凹透镜诱导的试验方法获得动物模型近视眼,并对获得的豚鼠近视眼模型进行生物力学研究,同时辅以组织学研究。方法选用出生后3周龄的豚鼠,实验眼眼前固定-10.0 D凹透镜,实验前后进行一系列生物力学测量,豚鼠喂养45 d后,摘除双眼球制作巩膜条带试件,在Instron-5544生物力学实验机上进行力学实验。部分样本置于4%甲醛中固定,予常规HE组织染色,显微镜下观察巩膜显微结构。结果豚鼠经过45 d的凹透镜诱导,实验眼与对照眼比较,诱导出(-8.95±0.60)D的相对近视,眼轴延长了(0.60±0.12)mm,前后变化差异有显著性。病理学观察结果:实验测量试验眼后部巩膜厚度为(0.32±0.11)mm,对照眼后部巩膜厚度为(0.43±0.05)mm,对数据进行分析,差异有显著性(P<0.05);近视眼巩膜尤其是后极部巩膜发生了退行性变化。生物力学研究结果:实验眼巩膜弹性模量小于对照眼,差异有显著性(P<0.05);实验眼蠕变率大于对照眼,差异有显著性(P<0.05);实验眼的最大载荷、最大应力均小于对照眼,实验眼的最大应变均大于对照眼,差异有显著性(P<0.05)。结论①凹透镜诱导可以引起幼豚鼠眼轴变长,发生明显轴性近视。②通过组织学观察可见,实验性近视眼后极部巩膜变薄,胶原纤维发生退行性变化。这是近视眼巩膜弹性差、容易发生变形、具有较低的承载能力的病理基础。③通过多个生物力学指标测量说明,实验性近视眼巩膜较正常眼巩膜弹性差,具有较低的承载能力,易发生变形。④预拉伸实验对于巩膜的拉伸实验研究是非常必要的。
Objective To use a lens-induced method to establiah a myopia model in the guinea pig and to study the biomechanical properties pathological changes in the sclera of the experimental eye model.Methods Twenty three-week-old guinea pigs wore - 10.0 D monocular lenses in one, eye to induce myopia. The contralateral eye, of each animal was untreated and used as a control, Refractive state, and axial length were measured before and after the experiment. After 45 days, scleral specimens were obtained and testing was done with the Instron-5544 biomechanical machine. Some spedmens were. examined under a microscope to observe pathological changes. Results （1）Eyes became myopic （-8.95±0.60）D and elongated （0.60± 0.12）mm 45 days after insertion of the lenses （P 〈0.05）. （2）Pathological changes were found ： the thickness of the posterior sclera in the lens-induced eye was （0.32 ± 0.11） mm while the. posterior sclera of the control eye was （0.43 ± 0.05 ） mm （ P 〈 0.05）. Vacuolar degeneration of collagen fiber in the posterior sclera also appeared. （3）Biomechanical changes in the sclera： the elastic modulus of the sclera in myopic eyes was lower than that in the sdera of normal eyes. Tne load limit and stress limit of the sclera in myopic eyes were lower than that of the sclera in normal eyes. The limit displacememt change, rate and the creep rate of the sclera in myopic eyes were higher than that in the sclera of normal eyes. There was a statistically significant difference between them （ P 〈 0.05 ）. Conclusion （1） Lenses can induce axial growth and lead to myopia in young guinea pigs. （2）The sclera in the experimental guinea pig myopia model is significantly thinner than the sclem of the contralateral eyes. Vacuolar degeneration of collagen fiber also appeared in the posterior sclera. （3）The biomechanica properties of the sclera are highly significant for myopia. The selera in myopic eyes has a lower load-hearing capacity than normal sclera and the eye is easily stretched out of shape. （4）Tension measurements in the pretest phase are a necessary step in biomechanical analysis.
出处
《眼视光学杂志》
CAS
2006年第4期209-213,共5页
Chinese Journal of Optometry & Ophthalmology
基金
国家自然科学基金资助项目(10272077)
关键词
近视/发生
形觉剥夺
凹透镜诱导
巩膜
生物力学
豚鼠
模型
动物
myopia/occurrence
shape sensory deprivation
lens-induced
sclera
biomechanical
guinea pig
models,animal
