Clinical reasoning: a rare cause of subarachnoid hemorrhage.

SECTION 1 A 48-year-old woman presented with severe headache radiating to her neck and chest, followed by a brief period of loss of consciousness in the emergency department. After she regained consciousness, the patient described a 2-year history of right-sided pulsatile tinnitus and hearing loss. She also had a history of poorly controlled hypertension and of noncompliance with her medication. On examination her blood pressure was 239/90 mm Hg. Results of a neurologic examination were unremarkable. Brain CT showed a subarachnoid hemorrhage (figure 1, A and B).