Primary intracranial hypotension is a spontaneous clinical syndrome ch
aracterised by postural headache due to low intracranial pressure. The
syndrome has a good prognosis. The symptoms improve spontaneously. A
diffuse meningeal enhancement on MRI in patients with primary intracra
nial hypotension was described several times, although the aetiology r
emains unknown. The case of such a patient is presented and the possib
le mechanisms are discussed.