A pain in the neck

A 49 year old right handed builder presented to the emergency department after an episode of vomiting and unsteadiness, with falling to the right side. This resolved after 10 minutes, but was followed 30 minutes later by pins and needles in the right face, arm, and leg. The symptoms had been preceded by bilateral neck stiffness for the previous three days, after the patient experienced minor trauma to the neck. His medical history was of well controlled essential hypertension. His family history was relevant—his father had a stroke in his 50s.

At initial assessment the patient was found to have right sided paraesthesia, with no evidence of weakness. He had no cranial nerve lesions and no higher cortical dysfunction. Initial observations were normal, with a blood pressure of 135/90 mm Hg. A 12 lead resting electrocardiogram showed sinus rhythm. Computed tomography of the head on admission showed no abnormality.

The next day the patient had residual paraesthesia in his right hand only. Fasting glucose and cholesterol concentrations were within normal limits, and his erythrocyte sedimentation rate was 10 mm/h. He underwent magnetic resonance imaging (fig 1⇓) and magnetic resonance angiography (fig 2⇓).