A COMPUTATIONAL STUDY OF THE OPTIC NERVE EVULSION

摘要

Optic nerve evulsion is a traumatic lesion of the optic nerve which is usually caused by high-speed traffic accidents, or a blunt object injury. The direct causes leading to nerve damage are not clear. We used a finite element model of the eye and the orbit to investigate the possible mechanisms of injury. The model, which involved the globe, optic nerve, recti muscles, and the orbital fat, was subjected to triangular acceleration pulses of peak intensity between 100 and 450g. Collision with a foreign object of cylindrical shape 6mm in diameter was used to simulate blunt object injury. The results point to rapid rotation of the globe, and a steep pressure gradient between the orbital fat and the soft tissue within the optic nerve as possible factors contributing to the optic nerve damage.