Mystery Case: Terson syndrome on CT head.

A 36-year-old woman presented with acute severe headache and generalized tonic-clonic seizures. CT head scan revealed a tentorial acute subdural hemorrhage (ASDH) and posterior globe hyperdensities suggestive of intraocular blood with a right posterior communicating artery aneurysm on cerebral angiography (figure 1). Ophthalmologic assessment confirmed Terson syndrome (figure 2). Terson’s original definition of intravitreal hemorrhage (IVH) complicating subarachnoid hemorrhage has broadened to include ASDH with retinal and preretinal hemorrhages as well as IVH. Plain CT head can demonstrate Terson syndrome, which is easily missed and warrants ophthalmologic input. Significant persisting visual impairment may require vitrectomy with or without laser membranotomy.