A 16-year-old girl presents to the emergency department with an acute-onset severe headache as well as nausea, vomiting, and intermittent diplopia. She feels dizzy while walking and cannot walk independently. She also complains of blurred vision. This is her first physician's visit for the headaches, which have been episodic during the past 2 weeks. The headaches involve her entire head. They are not throbbing and are not associated with an aura or a certain time of the day. The severity increases while coughing or straining. She has photophobia and phonophobia during these episodes. The headaches previously responded to over-the-counter analgesics, but now she has intolerable pain unrelieved by medications. She has no significant medical history, except for minor head trauma while cycling 1 month ago. Her only medication is an oral contraceptive that she has taken for 2 years. She denies any illicit drug use. The family history is positive for atypical migraine headaches; her mother has been treated with medications for this condition for years.
On physical examination, the patient is a normal-appearing teenager, but she is agitated due to her headache. She has a regular heart rate of 65 bpm, her blood pressure is 165/95 mm Hg, and her oral temperature is normal at 98.6°F (37°C). The general physical examination reveals no abnormalities in the head, neck, chest, abdomen, or extremities. A thorough neurologic examination is performed, which reveals decreased visual acuity in each eye to 6/10 (or about 20/30 US Standard). Ophthalmoscopy reveals papilledema, venous engorgement, and a diminished venous pulse. Bilateral sixth cranial nerve palsy is evident. Other neurologic examinations, including sensory and motor examinations, deep tendon reflexes, and cerebellar tests, are all within normal range.
During the initial assessment of the patient in the emergency department, she develops a generalized tonic-clonic seizure, which is immediately controlled with intravenous diazepam. Her blood pressure rises to 175/100 mm Hg, and her heart rate is 60 bpm after the convulsion. A repeat neurologic examination reveals bilateral extensor plantar reflexes and midsized pupils with slight reaction to light. After initiating a loading dose of intravenous phenytoin, an urgent computed tomography (CT) scan of the head is performed.
