Optochiasmal avulsion secondary to minor occipital trauma.

BACKGROUND: Optic nerve avulsion is an extremely rare occurrence and usually arises in the setting of severe fronto-orbital fractures or penetrating orbital injuries. However, a few cases have been associated with minor injury. OBJECTIVE: To overview the pathophysiology of delayed optochiasmal avulsion following minor ocipital trauma and discuss management options. METHODS: Report of a unique case of a 79-year-old woman who presented with delayed partial expulsion of the right globe and complete optic nerve avulsion following closed head injury to the occiput. CONCLUSION: Antero-posterior distortion of the skull following such a deceleration injury can cause laceration and thrombosis of the pre-chiasmal and pial arteries supplying the optic chiasm. The ensuing ischaemic changes subsequently caused delayed softening of the chiasm and its avulsion. The concomitant retrobulbar haemorrhage and mass effect within the orbit consequently led to the partial expulsion of the globe.