Dizziness caused by meningocele-associated intracranial hypotension in neurofibromatosis type 1

A 64-year-old man with neurofibromatosis type 1 (NF1) presented with falls caused by postural dizziness with negative prior workup including echocardiogram, telemetry, and tilt-table test. Neither discontinuing his β-blocker nor taking antihistamines, benzodiazepines, or antiemetics provided relief. Brain MRI demonstrated diffuse pachymeningeal enhancement (figure, A) and CT of the chest and MRI of the spine revealed large meningoceles arising from the thoracic spine (figure, B and C). Continuity of the meningoceles with cerebrospinal compartment was demonstrated with radionucleotide cisternogram (figure, D). Meningoceles are common in NF1 and can be mistaken as pleural effusions and lead to intracranial hypotension or tonsillar herniation if drained.1 Surgical intervention was considered but deferred because of difficulty in achieving dural closure with large meningoceles and complicated wound healing in NF1. With vestibular physical therapy, 6 months after hospitalization, he remained free of falls.