Surgical management of biventricular hydrocephalus caused by tuberculosis-induced bilateral obstruction of the foramen of Monro: illustrative case.

Background: Occlusion of the foramen of Monro is an exceedingly rare condition in adults and can lead to obstructive hydrocephalus. The authors present the first reported case of biventricular hydrocephalus caused by tuberculosis-induced bilateral obstruction of the foramen of Monro. They also discuss the technical nuances and surgical challenges associated with this condition.

Observations: A 47-year-old female presented with a 3-month history of short-term memory disturbances, ultimately leading to loss of consciousness. Neuroimaging revealed symmetrical biventricular hydrocephalus accompanied by periventricular interstitial edema. A lumbar puncture indicated lymphocytic-dominant pleocytosis and reduced glucose levels. During the endoscopic approach, significant stenosis of the foramen of Monro was noticed and monroplasty and septostomy were performed. Pathological examination revealed granulomatous inflammation. At the 1-year follow-up, the patient demonstrated significant clinical and radiological improvement, with resolution of symptoms and hydrocephalus.

Lessons: Tuberculosis-induced bilateral idiopathic occlusion of the foramen of Monro is an extremely uncommon cause of hydrocephalus. Neuroendoscopy allows for visualization, biopsy, and direct treatment of the obstruction simultaneously. While conservative management may be adequate for asymptomatic cases, neuroendoscopic procedures such as septostomy or foraminoplasty provide a minimally invasive option for restoring CSF flow, avoiding unnecessary shunt insertion in symptomatic cases. https://thejns.org/doi/10.3171/CASE25349.