Ventricular diverticula in obstructive hydrocephalus secondary to tumor growth

[Lateral ventricle diverticulum as a variant of hydrocephalus evolution]

A clinical case of a 12 year-old girl with hydrocephalus complicated by rare condition, lateral ventricular diverticulum, is reported. Progression of the diverticulum was followed up according to MRI. The diverticulum of the lateral ventricular wall has emerged in the interval of 1 year (14 months have passed between the two MRI examinations) and spread towards the quadrigeminal cistern. In addition, compression of cerebellum, aqueductus cerebri Sylvii, and the fourth ventricle of the brain have emerged. A surgical treatment was suggested after the hydrocephalus had been initially revealed (when the diverticulum had not been formed yet); however, the child's parents refused the therapy. One year later, a series of epileptic seizures emerged, and MR scans showed a cystic neoplasm in the postcranial fossa above the cerebellum. The genesis of the cyst and its nature were unclear and additional invasive examination methods were required. MSCT ventriculography confirmed the diverticulum of the right lateral ventricle towards the quadrigeminal cistern.

Reversible transinsular herniation of the lateral ventricle

We present a 7-year-old boy, with a history of neonatal intraventricular hemorrhage, leading to hydrocephalus with multiple shunt revisions. The current presentation of shunt failure and resultant hydrocephalus was complicated by herniation of the trigone of the lateral ventricle into the posterior fossa. Despite the dramatic radiological appearance, this herniation of the lateral ventricle was not accompanied by any additional clinical signs or symptoms other than those usually attributed to hydrocephalus. Following successful shunt revision, the patient returned to his baseline clinically with the trigone reverting back to its normal position. We also present a second companion case.