With The Change Of Pressure Within The Eyeball Volume And Finite Element Numerical Simulation Study

On the basis of former research on sclera, the thesis aims at the professional discussion on seepage during researches. In the mechanical research on sclera, seepage influenced results greatly, which results in unsatisfied one. Seepage is a relatively slow course, thus, It can be regarded as at an even speed at certain height. Through measuring seepage at the stage of pre-research, It can be discovered that seepage speed and height (pressure) are presented in laws of linearity. From this point, It is choosed half-height of INSTRON Instrument to measure seepage speed, and take this speed as mean of the whole circular research. Otherwise, in order to approach statement of eyeball more precise, adopted a method of three-seepage and two-circulation, and the final seepage speed equals the mean between measures before and after researches.From the formula It can calculated distortion:Δv = (h—kt)S And more distinct effects can be got than former through this method: the circular curve of eyeball mechanical capability reaches close nearly, and research error is avoided, and being more efficient and precise than former close method of sticking film. What's more, It can finded that vitro eye gets more seepage than vivo eye. Calculating the instantaneous eye eyeball hardness found in the beginning stage show more flexibility characteristics, and the continued increase in intraocular pressure, eyeball in the process of gradually expanding flexibility features to decline gradually viscoelastical obvious; In the same eye pressure. Instantaneous hardness in the eyes and the eyes larger than that in vitro.On the basis of whole measurement of eyeball, It established ANSYS Finite model of three- dimension shell, and re-organize measure and calculation of the eyeball size. Through measuring eyeball volume, left-right diameter, front-back diameter and radius vector,It seted up models by calculating thickness of comeal shell. The data during establishment of models adopts mean got by the measurement of former researchers, and get imitating results in the elastic statements of strength and strain. In the light of result, It can finded that near eyeball back-pole, there exist powerful strength and deformity, which coordinates with glaucoma theory reported in literatures and seepage phenomena of optic nerve found in researches. In a word, it shows that under high optic pressure, the organs around optic nerve would lose function at first. Model calculation of the instantaneous hardness and hardness relatively isolated both eyes instantaneous error. The model can be better reflect the flexible nature of the eyeball.