Journal article
A Cellular Solid Model of the Lamina Cribrosa: Mechanical Dependence on Morphology
Journal of biomechanical engineering, Vol.128(6), pp.879-889
12/01/2006
DOI: 10.1115/1.2354199
PMID: 17154690
Abstract
The biomechanics of the optic nerve head (ONH) may underlie many of the potential mechanisms that initiate the characteristic vision loss associated with primary open angle glaucoma. Therefore, it is important to characterize the physiological levels of stress and strain in the ONH and how they may change in relation to material properties, geometry, and microstructure of the tissue. An idealized, analytical microstructural model of the ONH load bearing tissues was developed based on an octagonal cellular solid that matched the porosity and pore area of morphological data from the lamina cribrosa (LC). A complex variable method for plane stress was applied to relate the geometrically dependent macroscale loads in the sclera to the microstructure of the LC, and the effect of different geometric parameters, including scleral canal eccentricity and laminar and scleral thickness, was examined. The transmission of macroscale load in the LC to the laminar microstructure resulted in stress amplifications between 2.8 and 24.5×IOP. The most important determinants of the LC strain were those properties pertaining to the sclera and included Young’s modulus, thickness, and scleral canal eccentricity. Much larger strains were developed perpendicular to the major axis of an elliptical canal than in a circular canal. Average strain levels as high as 5% were obtained for an increase in IOP from 15to50mm Hg.
Details
- Title: Subtitle
- A Cellular Solid Model of the Lamina Cribrosa: Mechanical Dependence on Morphology
- Creators
- E. A Sander - School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907 and Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118J. C Downs - Devers Eye Institute, Portland, OR 97232R T Hart - Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118C. F Burgoyne - Devers Eye Institute, Portland, OR 97232E. A Nauman - School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907
- Resource Type
- Journal article
- Publication Details
- Journal of biomechanical engineering, Vol.128(6), pp.879-889
- DOI
- 10.1115/1.2354199
- PMID
- 17154690
- NLM abbreviation
- J Biomech Eng
- ISSN
- 0148-0731
- eISSN
- 1528-8951
- Publisher
- ASME
- Language
- English
- Date published
- 12/01/2006
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Orthopedics and Rehabilitation; Craniofacial Anomalies Research Center; Chemical and Biochemical Engineering
- Record Identifier
- 9984064253902771
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