New-onset headache in an adolescent with MASS syndrome.

A 15-year-old girl with the "MASS" phenotype (meeting several of the minor criteria for Marfan syndrome) presents with a new onset low-pressure postural headache. Clinical features and magnetic resonance imaging suggested intracranial hypotension, which was confirmed with lumbar puncture. The pathophysiology and treatment of spontaneous intracranial hypotension are discussed.