Third ventricular diverticulum of the suprapineal recess can be a rare and confounding complication of chronic hydrocephalus: A case report with 2-year follow-up

PURPOSE

Chronic hydrocephalus is rarely seen in developed countries due to the widespread availability of CT scans for diagnosis and early treatment. In developing countries, it is more frequently encountered along with its rare complication of diverticulum formation.

METHODS

We report a case of a previously healthy 6 year old girl who presented with a 10 day history of headache, 3 day history of drowsiness and a single episode of generalized tonic clonic seizures. We review the literature on such cases and include imagining studies at follow up.

RESULTS

A CT scan done outside our hospital had been reported to be demonstrating a posterior fossa arachnoid cyst with resultant obstructive hydrocephalus. We first placed an external ventricular drain and performed an MRI of the brain to further characterize the lesion. It was again reported as an arachnoid cyst but on further scrutiny it was appreciated that it was in fact a third ventricular diverticulum of the suprapineal recess. She underwent ventriculoperitoneal shunt placement which led to resolution of the hydrocephalus as well as the diverticulum.

CONCLUSION

These diverticulae develop secondary to ventricular rupture in the setting of chronic untreated hydrocephalus. This pathology was first described in 1940 and over the years its identification has decreased due to a much lower incidence of chronic untreated hydrocephalus.

Expansion diverticulum of the suprapineal recess causing cerebellar ataxia. A case report

As a result of long-standing cerebrospinal fluid (CSF) pulsation against the thinnest segments of the ventricular walls, focal enlargement of the ventricular system (diverticulum) may occur, mainly at the medial wall of the trigone of the lateral ventricles (atrial diverticula) or at the posterior wall of the third ventricle (expansion of the suprapineal recess). In the latter case, ocular signs are the most common symptoms, due to the severe deformation of the periaqueductal region. We describe a case of non-communicating hydrocephalus in a 36-year-old woman who presented a three-year history of cerebellar ataxia. Preoperative brain magnetic resonance (MR) scan showed marked supratentorial hydrocephalus with an apparently patent aqueduct of Sylvius, and an enlarged suprapineal recess causing cerebellar and tentorial dislocation. The patient was successfully treated by endoscopic third ventriculostomy and monitored by MR scans with phase-contrast sequences for assessment of CSF flow. Cerebellar ataxia is a very rare symptomatic onset for a suprapineal recess expansion diverticulum, which may cause obstructive hydrocephalus that can be effectively treated by endoscopic third ventriculostomy.