Evulsion of the optic nerve following blunt bulbar trauma - Case report and review of literature

Background: Evulsion of the optic nerve is a rare form of traumatic optic neuropathy. It is a rupture of the optic nerve at the disc without damage of its sheaths occurring in association with a blunt skull trauma or a blunt bulbar trauma. Method: We report on a 13-year old girl with complete evulsion of the optic nerve after blunt bulbar trauma and give a literature review. Results: While swinging on a liana the patient had crashed into a tree. The initial examination 3 hours after the accident revealed at the right eye an amaurosis without any afferent reaction of the pupil to light. Ophthalmoscopy displayed a vitreous haemorrhage at the optic disc, peripapillar white retina and interruption of the blood flow of all visible retinal vessels. Fluorescein angiogram showed no retinal perfusion and a teared off retina above the disc. Echographic examination revealed a vitreous haemorrhage at the disc shaped like a mushroom. From the eighth day, examination of the retina became impossible due to disseminating vitreous haemorrhage. After 8 months vitreous haemorrhage had disappeared revealing a white fibrosis at the area of the optic disc. Since first histological description of an optic nerve evulsion by His in 1856, 42 patients with complete and 23 with partial evulsion of the optic nerve were reported in the literature. In our review different mechanisms of injury are discussed. Conclusion: Evulsion of the optic nerve is rarely reported. It is possible that it may occur more frequently, because it cannot be seen in blunt or also penetrating bulbar traumas with severe intraocular cloudiness.