Unusual Post-COVID-19 Presentation With Tetraventricular Hydrocephalus: A Case Report.

Objective: COVID-19 infection is suggested as one of the causes for hydrocephalus (HCP) of unknown etiology. COVID-19 infection may present with a range of neurologic symptoms given viral neurotropic and neuroinvasive properties. Postinfectious HCP is a severe complication as a potential sequela of COVID-19 infection. Methods: We identified a patient with a history of recent COVID-19 infection who presented with chronic progressive headaches with nausea, vomiting, and blurry vision over 2 weeks. Results: Neurologic examination showed bilateral papilledema. The head CT scan showed tetraventricular enlargement and marked fourth ventricular dilation. Cine MRI showed fourth ventricular turbulent CSF flow. The patient underwent external ventricular drain placement and exploratory suboccipital craniotomy, which revealed a subarachnoid web that was microsurgically resected. Reconstituted CSF flow resolved the patient's symptoms and prevented complications. Discussion: Fourth ventricular outlet obstruction is a rare cause of tetraventricular HCP. In most cases, it is associated with a history of inflammatory conditions or hemorrhage. In our case, a history of recent COVID-19 infection and normal imaging before COVID-19 make COVID-19 the most probable explanation for HCP. We suggest considering COVID-19 infection in the differential diagnosis of HCP of unclear etiology.