Recurrent Thunderclap Headache

Reversible cerebral vasoconstriction syndrome (RCVS) is a transient disturbance in cerebral vascular tone with subsequent multifocal segmental intracerebral arterial constriction and dilation. It typically presents with recurrent thunderclap headaches, and with focal neurological deficits if cerebral infarction has occurred. Cerebral angiography demonstrates multifocal segmental narrowing and dilatation which normalises within three months. Differentiation from primary CNS angiitis can be made clinically, and from aneurysmal subarachnoid haemorrhage radiologically. Management includes enquiring about and discontinuing any potential precipitants and commencement of calcium channel blockers may be beneficial. Prognosis is favourable, but dependent on the extent of cerebral infarction.