Finite element analysis and experimental evaluation of penetrating injury through the cornea. (February 2017)

• Record Type: Journal Article
• Authors: Lovald, Scott T.; Rau, Andrew; Nissman, Steven; Ames, Nicoli; McNulty, John; Ochoa, Jorge A.; Baldwinson, Michael
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 66(2017)
• Page Start: 104
• Page End: 110
• Publication Date: 2017-02
• Subjects: Penetrating eye injury -- Corneal perforation -- Corneal laceration -- Corneal rupture -- Traumatic eye injury -- Finite element analysis; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2016.11.001
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Penetration injuries of the eye are among the most frequent causes of permanent visual impairment resulting from trauma. The purpose of this study was to determine the peak strain at which rupture occurs in the cornea due to a penetrating object. Probes of varying diameters (1.0, 1.5, and 2.0 mm) were pressed into the apex of the cornea of 36 human cadaveric eye specimens until perforation or rupture of the specimen at the cornea, limbus, or sclera occurred. An axisymmetric finite element model of the human globe was created to replicate the experimental set-up. The models were used to map the force-displacement response of the experiments and quantitatively determine a peak strain at which the eye ruptures. For the experiments, the average force at failure increased from the smallest to largest probe (p<0.002). The average forces at failure are as follows: 30.5±5.5 N (1.0 mm probe); 40.5±8.3 N (1.5 mm probe); 58.2±14.5 N (2.0 mm probe). The force-displacement responses of the finite element models of all three probe sizes bounded and tracked the experimental data. In all cases, the peak strain at failure in the cornea was located on the posterior surface of the cornea, directly adjacent to the corneal apex. This strain was in the range of 29% to 33% for all models analyzed. In addition to determining an objective failure strain of corneal tissue, the model developed in this study can provide quantitative information for understanding the risk of penetrating eye injuries.