Spontaneous lateral ventriculocisternostomy documented by metrizamide CT ventriculography. Case report

[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.

Relocation of ventricular catheter trough ventriculostomy due to congenital unilateral hydrocephalus: Nine year follow-up

Background:

Congenital unilateral hydrocephalus is an uncommon entity occurring almost exclusively in children. Atresia, stenosis, membranous occlusion and even functional obstruction of the foramen of Monro have been described to be the main cause of this type of hydrocephalus. There are two options available in the surgical management of unilateral hydrocephalus: one is the placement of shunt CSF diversion from the dilated ventricle and the other is fenestration of the occluded foramen of Monro or septum pellucidum by endoscopy or by stereotactic method. Migration of the ventriculoperitoneal (VP) shunt in or out of ventricles is not so uncommon, but the relocation of the ventricular tip of a catheter from the ventricle into the quadrigeminal cisterns and superior vermis in association with ventriculostomy is extremely rare. Spontaneous ventriculostomy is a rare event and results from spontaneous rupture of a ventricle into the subarachnoid space.

Case Description:

A 5½-month-old baby with a right-sided congenital unilateral hydrocephalus underwent a VP shunt andhad experienced an uneventful outcome. Four years later on an MR imaging examination, the tip of the ventricular catheter passing through the medial wall of the ventricle and the quadrigeminal cistern was found to be situated in the superior vermis. During the follow-up period, there were no neurological difficulties. The cognitive and motor skill development corresponded well with the child's age. It transpired that the hydrocephalic ventricle reduced its size dramatically to normal.

Conclusion:

We have described the extremely rare site of the relocation of the ventricular catheter after the treatment of the congenital unilateral hydrocephalus by VP shunting. Spontaneous ventriculostomy as a rare phenomenon may be the explanation of the relocation of the ventricular catheter.

Phase-contrast cine MRI revealing en valve mechanism in spontaneous third ventriculostomy: report of a case and literature review

A 50-year-old epileptic woman affected by hydrocephalus due to aqueductal stenosis was admitted to the hospital because of headache, dysarthria, and mild lateral pulsion. Cranial computed tomography (CT) revealed left cerebellar hemorrhage. Subsequent magnetic resonance imaging (MRI) of the brain demonstrated an enlarged ventricular system unchanged from prior studies. Flow-sensitive phase-contrast (PC) cine magnetic resonance imaging showed flow absence through the aqueduct and flow pulsations through the third ventricle floor in systole and diastole, consistent with spontaneous third ventricle patency. On stationary tissue images, the third ventricle floor and the mamillary body were displaced downward at systole and upward at diastole. Stenosis of the cerebral aqueduct of Sylvius was also shown. Retrospective evaluation of the sagittal T2-weighted images disclosed flow void at the level of the third ventricle floor. On-off movements of the third ventricle floor could account for chronic hydrocephalus persistence by an en valve mechanism. Spontaneous third ventriculostomy (STV) was diagnosed on the basis of these findings. STV is a rare condition occurring in chronic obstructive hydrocephalus patients as a result of longstanding pulsations against the walls of the third ventricle, the floor in particular. We reviewed the literature to establish which imaging and clinical findings could improve the identification of STV in patients affected by obstructive hydrocephalus.

Spontaneous third ventriculostomy: definition by endoscopy and cerebrospinal fluid dynamics

Chronic obstructive hydrocephalus is known to cause ventricular diverticula and, rarely, spontaneous ventriculostomy. The authors present the case of a patient in whom a spontaneous third ventriculostomy was identified with long-standing hydrocephalus secondary to aqueductal stenosis. To their knowledge, this is the first report in which a spontaneous stoma in the floor of the third ventricle was evaluated using endoscopy and cerebrospinal fluid dynamics studies. Both studies confirmed that the spontaneous stoma is similar in structure and function to surgical third ventriculostomy.

Spontaneous third ventriculocisternostomy in an infant with obstructive hydrocephalus

Spontaneous ventriculocisternostomy, the spontaneous communication between the ventricular system and the subarachnoid space, is rare. The authors report a case of an infant with obstructive hydrocephalus who developed a spontaneous third ventriculocisternostomy. The infant was initially evaluated for progressive ventriculomegaly and increasing head circumference (HC). During follow-up, the patient's HC began to follow percentile lines and magnetic resonance (MR) imaging demonstrated a reduction of the hydrocephalus. Flow-sensitive phase-contrast cine MR images revealed cerebrospinal fluid (CSF) flow through the floor of the third ventricle between the tuber cinereum and the mammillary bodies connecting the ventricular system with the prepontine cistern. Although rare, clinicians should be cognizant of this phenomenon as it may eliminate the need for CSF diversion.

Ventricular diverticula in obstructive hydrocephalus secondary to tumor growth

OBJECTIVE

The association of ventricular diverticula with intra- and paraventricular tumors causing obstructive hydrocephalus has rarely been reported.

METHODS

Records and imaging findings for 57 patients with obstructive hydrocephalus caused by tumors who were treated at our institution were reviewed for the presence of ventricular diverticula. For the anatomic study of ventricular diverticula, data were collected from five cadaveric heads.

RESULTS

Ventricular diverticula were identified on magnetic resonance imaging scans in five cases. Diverticula were similarly located in the quadrigeminal cistern but originated from the medial wall of the atrium of the lateral ventricle in three cases and from the superior portion of the fourth ventricle in two cases. Regression of diverticula occurred in all cases after either insertion of a shunt or removal of the obstructing tumor. The cadaveric study suggested that the choroidal fissure and the rostral portion of the superior medullary velum might be the origins of diverticula from the atrium and from the superior portion of the fourth ventricle, respectively.

CONCLUSION

Ventricular diverticula should be distinguished from other cystic lesions in the quadrigeminal region. Detection of an ostium of a diverticulum or communication between the cyst and the ventricular system is important for diagnosis.

Subtentorial diverticulum of the third ventricle associated with a mural cavernous angioma in a child

The authors describe a case of a large subtentorial supracollicular diverticulum of the third ventricle associated with a cavernous angioma in its wall in a 6-year-old girl who presented with developmental delay and obstructive hydrocephalus. This is the first case in which such association has been diagnosed and successfully treated. The literature is reviewed, and the possible relationship between these two rare lesions is discussed.

Diverticulum of the lateral ventricle causing cerebellar ataxia. Case report

A case of ventricular diverticulum causing cerebellar ataxia is presented. Computerized tomography clearly demonstrated the aperture of the diverticulum in the medial wall of the trigone and its extension into the posterior fossa. The diverticulum regressed and the cerebellar ataxia disappeared after placement of a ventriculoperitoneal shunt.