Isolated fourth ventricle as a complication of ventricular shunting. Report of three cases.

Signs of cerebellar dysfunction combined with signs suggestive of shunt malfunction developed in three children with obstructive hydrocephalus. Shunt function was normal. In all cases, the cerebellar signs persisted and computerized tomography scans revealed enlargement of the fourth ventricle. Shunting of the fourth ventricle returned the patients to normal function.     

Resolution of a fourth ventricle epithelial cyst after ventriculoperitoneal shunting: case report

BACKGROUND: Symptomatic cysts of epithelial origin occurring in the fourth ventricle are very rare. When such a cyst is encountered, the treatment strategy includes surgical removal or fenestration of the cyst into subarachnoid space. CASE 1: A 23-year-old male was diagnosed as having a cyst located in the fourth ventricle causing hydrocephalus; the patient underwent cyst removal via craniotomy. The histopathologic diagnosis was neuroepithelial cyst. Because clinical and neuroradiological findings persisted, he underwent VP shunting. The cyst disappeared and did not recur. CASE 2: A 54-year-old woman was diagnosed as having a cystic mass in the fourth ventricle and dilatation of the ventricles. Magnetic resonance imaging showed the same findings as those of the first case. The patient refused craniotomy for total mass excision. Therefore, a VP shunt was applied. Postoperatively, the clinical findings and hydrocephalus improved, and complete disappearance of the cystic mass was observed unexpectedly. Both cases had 2 years of follow-up. CONCLUSION: There is no proven mechanism to explain resolution of fourth ventricle cysts after a supratentorial VP shunting. We hypothesize that disappearance of the cyst could result from rupture of its wall because of pressure gradient, which might be facilitated by a VP shunt. The current report should not be taken as an argument against cyst removal, which is the established way of treatment. However, considering that the pathogenesis and pathophysiology of these cysts are unclear, VP shunting should be considered especially for recurrent cases accompanied by hydrocephalus.     

A case of disproportionately large communicating fourth ventricle after resection of temporal astrocytoma that evolved an isolated fourth ventricle]

The isolation and enlargement of the fourth ventricle after a ventriculoperitoneal (V-P) shunt was classified as "isolated fourth ventricle (IFV)". The term, "disproportionately large communicating fourth ventricle (DFV)" was first introduced by Scotti et al as being an enlarged fourth ventricle communicating with the third ventricle. The authors present a case of DFV after the resection of an astrocytoma. Upon recurrence of the tumor a second resection was carried out 5 years later. It was found that IFV had evolved because a cyst in the right temporal lobe was obstructing the aqueduct. After shunting of the tumor cyst, the aqueduct was again found to be patent and the fourth ventricle gradually decreased in size. A 34-year-old female presented headache, nausea, and a mild left hemiparesis. An initial CT scan demonstrated a fourth ventricle of approximately normal size and a right temporal mass. The first craniotomy revealed an astrocytoma. A CT scan after the surgical procedure showed enlargement of all ventricles, especially the fourth, resulting from the blockage of the foramina of Luschka and Magendie. The insertion of a V-P shunt was followed by a reduction in size of all ventricles. The diagnosis of DFV was thus confirmed because the fourth ventricle had a demonstrated communication with the third ventricle. After a second craniotomy for tumor recurrence five years later, a CT scan revealed the enlargement of the fourth ventricle and a cyst in the right temporal lobe. A metrizamide CT scan revealed that the cyst was isolated and an RI ventriculogram confirmed obstruction of the aqueduct.(ABSTRACT TRUNCATED AT 250 WORDS)     

Neuroendoscopic aqueductal stent placement procedure for isolated fourth ventricle after ventricular shunt placement. Case report

Isolated fourth ventricle (IFV) is a rare complication in patients who undergo shunt placement, and it is not easily corrected by surgical procedures. The authors report a case of IFV that was successfully treated with an aqueductal stent placed under direct visualization by using a neuroendoscope. This 36-year-old suffered meningitis after partial resection of a brainstem pilocytic astrocytoma, and subsequently developed hydrocephalus for which a ventriculoperitoneal shunt was placed. Nine months later, the patient presented with progressive cerebellar ataxia, and magnetic resonance imaging revealed slitlike supratentorial ventricles and a markedly enlarged fourth ventricle, which were compatible with the diagnosis of IFV. The surgical procedure described was performed under visualization through a styletlike slim optic fiberscope inserted into a ventricular catheter. The catheter, with the endoscope inside it, was passed through the foramen of Monro and then through the aqueduct to reach the enlarged fourth ventricle, where membranous occlusion of the foramen of Magendie was clearly visualized. The tip of the catheter was placed in the fastigium of the fourth ventricle. After the procedure, the size of the fourth ventricle was reduced and the patient's symptoms improved. Thus, it is concluded that endoscopic aqueductal stent placement is a simple and safe surgical procedure for treatment of IFV.     

Myxochondrosarcoma of the fourth ventricle. Case report.

The authors report a case of myxochondrosarcoma of the fourth ventricle. The tumor was heavily calcified and proved impossible to remove at surgery. Histological examination revealed areas of loose fibroblastic tissue, hyaline cartilage, osteoid, and bone. It is postulated that the tumor arose from the stroma of the choroid plexus.     

Trapped fourth ventricle

Summary A case of cystic dilatation of the fourth ventricle which developed after surgery on an arteriovenous malformation is presented with a discussion of the pathogenesis of the trapped fourth ventricle.     

Encysted fourth ventricle

A case of an encysted fourth ventricle subsequent to meningitis is described. This clinical entity may cause a progressive neurological deficit secondary to mass effect and recurrent central nervous system infections. Direct drainage, as opposed to lateral ventricular shunting alone, is indicated.     

Meningiomas of the fourth ventricle

Resumen Se presentan dos casos de meningiomas intraventriculares del cuarto ventrículo, señalando la rara ocurrencia de los mismos. En la literatura revisada solo fue posible encontrar cuatro.Se Ilama la atención sobre el hecho de que los dos casos ocurrieron en niños por debajo de los 12 años, en quienes son raros los meningiomas de la fosa posterior.

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Summary Two cases of intraventricular meningioma arising in the IV ventricle are reported.The rarity of such localization must be pointed out: only four cases were found in the reviewed literature and the two cases described occurred in children below 12 years of age in whom meningiomas of the posterior fossa are very seldom seen.

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Zusammenfassung Es werden zwei Fälle von intraventrikulären Meningiomen im IV. Ventrikel beschrieben.Die Seltenheit dieser Lokalisierung muß hervorgehoben werden: nur vier solcher Fälle wurden in der Literatur gefunden. Die zwei beschriebenen Fälle betrafen Kinder unter 12 Jahren, bei denen Meningiome der hinteren Schädelgrube sehr selten zu finden sind.

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Résumé On présente deux cas de méningiomes intraventriculaires du IV ventricule. On sait la rare fréquence de telles tumeurs dont dans la littérature révisée on a trouvé seulement quatre.Il faut aussi remarquer que ces deux cas se sont présentés chez des enfants au-dessous de douze ans chez lesquels les méningiomes de la fosse postérieure sont trop rares.

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Riassunto Vengono riportati due casi di meningioma intraventricolare con accrescimento nel IV⁰ ventricolo. La rarità di tale localizzazione è da rilevare: soltanto 4 casi sono stati riscontrati nella letteratura.I due casi descritti si riferiscono a bambini sotto i 12 anni, nei quali il meningioma della fossa posteriore è molto raro.

     

Germinoma in the fourth ventricle

Summary ¶A 33-year-old male presented with trigeminal, abducens, and facial nerve pareses associated with cerebellar signs. Magnetic resonance imaging showed a homogeneously enhanced mass occupying the lower half of the fourth ventricle and attached to the floor of the fourth ventricle. The mass was subtotally removed. The histological diagnosis was pure germinoma. Neuro-imaging cannot distinguish germinoma in the fourth ventricle from ependymoma. Germinoma in the fourth ventricle is extremely rare and requires histological differentiation from ependymoma to determine the indications for adjuvant irradiation and/or chemotherapy.Published online July 25, 2003     

Trapped fourth ventricle treated with shunt placement in the fourth ventricle by direct visualization with flexible neuroendoscope.

Shunt placement was the most common procedure used for ventricular dilatation, but in many neurosurgical centers it has been substituted by flexible neuroendoscope; however, none of them had solved the problem of the trapped and dilated fourth ventricle. The combination of the ventricle-peritoneal catheter placement in the center of the fourth ventricle by direct visualization with a flexible neuroendoscope using a single coronal burr-hole has solved this problem. Eleven patients with a trapped fourth ventricle, with previous third ventriculostomy and aqueductal plasty, were treated with this procedure; all patients were evaluated clinically and with computed tomography 8 to 24 months (mean, 18 months) later. Here, we describe the technical procedure.     

A case of isolated fourth ventricle due to ruptured cerebral aneurysm

We present a case of isolated fourth ventricle which developed after massive ventricular hemorrhage, due to a ruptured cerebral aneurysm. In an adult an isolated fourth ventricle seems to be very rare, also the symptom of unconsciousness and respiratory arrest and the rapid development in this case seemed very unusual. The aqueductal occlusion was considered to be related to the intraventricular hematoma which remained as clots over a 2-month-period of time. This case was a 57-year-old woman admitted to our hospital in a state of coma. CT showed a massive ventricular hematoma and right carotid angiogram showed an aneurysm of the anterior communicating artery. Bilateral ventricular drainage was performed because of progressive decerebrate rigidity. Since consciousness gradually arose to the Japan Coma Scale 3, clipping of the neck of the aneurysm was performed 25 days after onset. Premature rupture occurred during the operation. After surgery, CT Showed ring-like high densities due to the premature rupture of aneurysm in both lateral ventricles, and also in the fourth ventricle as well. Although the lateral ventricles drainage functioned effectively, the fourth ventricle showed remarkable gradual dilatation. The patient was stuporous, but respiratory arrest occurred suddenly 43 days after onset. Since it was considered that the intraventricular hematoma blocked the aqueduct, the same as in the outlet of the fourth ventricle and that the dilated fourth ventricle compressed the brain stem, the ventriculostomy was performed through suboccipital craniectomy. The cerebellar hemispheres showed remarkable swelling bilaterally, and no cerebrospinal fluid was found in the cisterna magna.(ABSTRACT TRUNCATED AT 250 WORDS)     

Massive acquired omental cyst as a complication of ventriculo-peritoneal shunting

A case of massive acquired omental cyst in a 13-year-old girl as a complication of ventriculo-peritoneal (VP) shunting is reported. This is the first such case to be reported. Most complications of VP shunting involve shunt blockade, infection, or both. The absence of shunt blockade, infection or inflammation, and associated symptoms in this case permitted the acquired omental cyst to reach a massive size before detection; the cyst was managed successfully by simple resection of a large part of its thin wall.     

Migration of ventriculo-peritoneal shunt into lateral ventricle of an adult.

Migration of an entire ventriculo-peritoneal shunt into the lateral ventricle of an adult patient with chronic hydrocephalus is presented. The possible causes are reviewed.     

Central neurocytoma of the fourth ventricle. Case report.

The authors report on a 17-year-old boy who suffered from slowly progressive and long-standing symptoms of ataxia, neck pain, and headache. Computerized tomography (CT) and magnetic resonance (MR) imaging revealed a tumor arising from the floor of the fourth ventricle that resulted in a moderate hydrocephalus. A partial resection was performed. Histological and immunohistological findings led to the diagnosis of an atypical central neurocytoma of the fourth ventricle. The imaging features on CT scanning, MR imaging, and proton MR spectroscopy studies, the clinical picture, and the prognosis of this very unusual tumor are discussed. Three cases of neurocytomas in the posterior fossa have been described to date; however, in all three cases some atypical aspects were present. In the present case, with the exception of the very unusual location, both imaging findings and clinical history perfectly met the definition of this rare tumor.     

Brain stem auditory evoked potentials for assessment of isolated fourth ventricle in three patients

Isolated fourth ventricle is an untoward but interesting complication caused by the shunt procedure, which has been recognized since the introduction of CT scanning. Auditory brain stem evoked potentials (BAEPs) were recorded in a patient with isolated fourth ventricle for assessment of brain stem function. Case 1. A 9-year-old boy. He had undergone repair of the lumbosacral meningocele at birth, followed by shunting procedures, including repeated shunt revision, for hydrocephalus which subsequently developed. CT scanning on admission revealed typical findings of isolated fourth ventricle, while neurological examination disclosed no abnormalities. BAEPs on admission revealed normal waves both in amplitude and latency. This patient has been doing well without further shunting procedures. Case 2. A 17-year-old male was admitted with complaints of headache, diplopia, nystagmus and ataxic gait. He had a history of operation for radical removal of cerebellar astrocytoma and lateral ventriculo-peritoneal shunt at 9 years of age. CT scanning on admission revealed a typical isolated fourth ventricle, and fourth ventricle-peritoneal shunt was performed. Postoperative serial BAEPs revealed gradual improvement of brain-stem function. Clinically he has been symptom-free thereafter except for slight nystagmus. Case 3. A 2-year-old female suffering from hydrocephalus developed after neonatal intraventricular hemorrhage and ventriculitis. After repeated revision of a lateral ventriculo-peritoneal shunt, she was admitted in semicoma with vomiting and opisthotonic posture. CT study revealed an isolated fourth ventricle and preoperative BAEPs showed marked abnormalities. Although fourth ventricle-peritoneal shunt was performed, no remarkable change in BAEPs was obtained, and neurological deficit of considerable degree persisted.(ABSTRACT TRUNCATED AT 250 WORDS)