A 73-year-old woman with a history of hypertension and diabetes presented with sudden headache and right-sided periorbital ecchymosis (figure). There was no history of trauma. Neurologic examination was unremarkable. Ophthalmologic examination revealed normal vision and intact ocular movements and no papilledema or retinal hemorrhage. CT angiography showed subarachnoid hemorrhage (SAH) from a right ophthalmic artery aneurysm (figure). The patient underwent successful endovascular treatment and made a full recovery. In addition to skull fracture and cavernous sinus thrombosis, SAH is an important differential diagnosis of sudden severe headache with periorbital ecchymosis.