Purpose: To present the magnetic resonance imaging findings for a patient with traumatic oculomotor nerve injury.
Methods: We examined a patient with a right pupil-involving oculomotor nerve palsy after severe closed head trauma.
Results: Magnetic resonance imaging of the brain demonstrated marked signal hypointensity on gradient-echo T2*-weighted images consistent with hemorrhage at the midbrain exit site of the right oculomotor nerve.
Conclusions: Distal fascicular damage or partial rootlet avulsion is a mechanism of injury in some traumatic oculomotor nerve palsies. Gradient-echo T2*-weighted magnetic resonance imaging is the most sensitive method to detect hemorrhagic changes associated with shearing injury.