Numerical simulation of the relationship between apparent elastic modulus and tissue elastic modulus of the trabecular meshwork in rats

doi:10.12307/2023.856

Abstract

Abstract: BACKGROUND: The tissue mechanical properties of trabecular meshwork are closely related to the resistance of the aqueous humor outflow. Considering the porous structure of trabecular meshwork, the apparent elastic modulus of trabecular meshwork tissue can be obtained by atomic force microscope indentation technique. However, the information of tissue elastic modulus cannot be obtained by this method. Therefore, there is a lack of quantitative research on the relationship between apparent and tissue elastic modulus of the trabecular meshwork.
OBJECTIVE: To further analyze the relationship between apparent and tissue elastic modulus of the trabecular meshwork by finite element simulation.
METHODS: Based on the two-photon confocal images of rat trabecular meshwork, a three-dimensional structure model of the trabecular meshwork was constructed. The finite element analysis was used to simulate the indentation experiment to obtain the apparent elastic modulus of the trabecular meshwork at different positions, and the tissue elastic modulus was obtained by simulating the whole indentation experiment.
RESULTS AND CONCLUSION: The parameters of the first-order Ogden model based on the atomic force microscope indentation experiment were obtained. The average value of the apparent elastic modulus of the trabecular meshwork obtained by simulating the atomic force microscope indentation experiment was within the range of the tissue elastic modulus of the trabecular meshwork tissue when the compression ratio was 1%-2%. This study quantifies the relationship between apparent and tissue elastic modulus of trabecular meshwork tissue and provides a methodological reference for the study of mechanical properties of trabecular meshwork tissue.

Key words: trabecular meshwork, elastic modulus, finite element analysis, indentation test, Hertz model

CLC Number:

Wang Chuan, Wang Jinhang, Liu Rundong, Zhang Jing, Li Lin, Liu Zhicheng. Numerical simulation of the relationship between apparent elastic modulus and tissue elastic modulus of the trabecular meshwork in rats[J]. Chinese Journal of Tissue Engineering Research, 2023, 27(35): 5649-5652.

Figures/Tables 4

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