[Establishment and pathophysiological observation of an experimental animal model of traumatic optic neuropathy]

To establish an animal model of traumatic optic neuropathy (TON) that resemble to clinical state and study the mechanical principle and change of pathophysiology of its nerve injury for clinical diagnosis and treatment.

New Zealand white rabbits were used as the research objects. The method introduced by Wang Yi was repeated and improved. Mild and severe animal models of TON were established by reformed Wang Yi operation separately. After the spring gun struck, all animals were observed on pupils and direct light reflex and received the examinations of pattern reversal visual evoked potentials (PR-VEP). The pathophysiology of normal and injury optic nerve was observed.

After recovery from anesthesia, the mydriasis and disappearance or dullness of direct light reflex happened in all injured eyes. No brain contusion, infection, orbital fracture and death were found. One optic nerve was broken with complete tunica vaginalis. The latency and amplitude of injured eyes deteriorated gradually. In group B, the waves became flat rapidly. After injury, the optic nerve underwent 3 stages: edema, hyperplasia and atrophy. The pathomorphological changes of injured eyes in group B were more serious than that in group A in any time.

The reformed operation can establish constant nerve injury with high success rate. In mildly injured eyes, the injury deteriorated gradually. However, part visual function remained. In severely injured eyes, the pathomorphological changes were irreversible sooner after struck, and the visual function lost completely. There is a good correlation between PR-VEP and pathomorphology. PR-VEP can guide the clinical diagnosis and treatment.