A rare case of intralesional haemorrhage of a benign aqueductal cyst after CSF diversion treatment. A case report and review of literature.

Benign cysts within the pure aqueductal region are a rare entity. Their critical location within the ventricular system presents a risk of potentially catastrophic outcomes. We present a case of a 68-year-old female who was transferred to our unit with an acute obstructive triventricular hydrocephalus caused by a benign cyst within the cerebral aqueduct. She became unconscious and had an urgent endoscopic third ventriculostomy (ETV). Post-operatively, the patient was recovering well but then developed a sudden onset severe headache accompanied by vomiting. Imaging revealed intracystic haemorrhage with expansion of lesion but there was no obstructive hydrocephalus due to CSF diversion performed 9 d prior. She was treated conservatively and continued to improve.