Two Cerebrospinal Fluid (CSF) Diversion Procedures for Two Separate CSF Pathologies in a 19-Year-Old Male: A Case Report.

Hydrocephalus is a dynamic neurosurgical entity, with cerebrospinal fluid (CSF) diversion methods continually evolving to strike a balance between long-term efficacy and the risk of complications. We describe a 19-year-old man who was treated with endoscopic third ventriculostomy (ETV) for congenital aqueductal stenosis, with initial relief of symptoms. Two years later, he experienced recurring headaches and papilledema, but neuroimaging showed stable ventricles and patency of the ETV stoma. Magnetic resonance venography (MRV) ruled out venous sinus thrombosis, while lumbar CSF manometry revealed persistently elevated intracranial pressure (ICP), consistent with CSF absorption dysfunction. Given his refractory symptoms despite medical therapy, a lumboperitoneal (LP) shunt was placed, leading to complete resolution of symptoms and papilledema. This case underscores the paradox of post-ETV intracranial hypertension, reinforcing that a patent ETV does not equate to normal CSF dynamics. Integrating continuous ICP monitoring, advanced CSF flow imaging, and personalized diversion strategies may enhance long-term outcomes in this complex subset of hydrocephalus patients.