Traumatic dysfunction of the optic chiasm.

Abstract

Trauma of the optic chiasm has been reported but its incidence is low. Retrospective review of patients diagnosed with traumatic optic neuropathy between 1992 and 2002. Among 91 patients with a diagnosis of traumatic optic neuropathy, 10 showed evidence of optic chiasm involvement. All were males, the average age was 32 years (range 22-43). Injuries resulted from a rapid deceleration in 8 cases (car or motorcycle accident or fall from a minimum height of 5 meters). Coma was present in 6 cases and neurologic disorders in 8 cases. Optic neuropathy was present in 8/10 cases. Visual improvement was noted in two patients who suffered from milder head trauma. Optic chiasm dysfunction following head trauma is not that rare, as 11 % of our traumatic optic neuropathy group presented such a dysfunction. In some cases the visual field defect was obvious, but in some others it was more subtle. Visual prognosis was generally poor, probably related to the the severity of the impact.