Neurosarcoidosis Presenting with Obstructive Hydrocephalus Successfully Treated with Endoscopic Third Ventriculostomy

A 58-year-old Japanese woman complained of unstable gait and dizziness lasting for a month. She had been diagnosed histologically with pulmonary and cutaneous sarcoidosis and attended outpatient clinics for routine checkups. Head computed tomography and magnetic resonance imaging (MRI) indicated obstructive hydrocephalus caused by a contrast-enhanced lesion in the cerebral aqueduct. The patient underwent endoscopic third ventriculostomy and a biopsy of the lesion, leading to the diagnosis of neurosarcoidosis. This was a rare case of neurosarcoidosis presenting with obstructive hydrocephalus that was treated with endoscopic third ventriculostomy and diagnosed histologically via an intraoperative biopsy.