Posterior fossa craniotomy for trapped fourth ventricle in shunt-treated hydrocephalic children: long-term outcome

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Trapped fourth ventricle (TFV) is a rare late complication of postinfectious or posthemorrhagic hydrocephalus. This entity is distinct from a large fourth ventricle because TFV entails pressure in the fourth ventricle and posterior fossa due to abnormal inflow and outflow of CSF, causing significant symptoms and signs. As TFV is mostly found in children who were born prematurely and have cerebral palsy, diagnosis and treatment options are a true challenge.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Between February 1998 and February 2007, 12 children were treated for TFV in Dana Children's Hospital by posterior fossa craniotomy/craniectomy and opening of the TFV into the spinal subarachnoid space. The authors performed a retrospective analysis of relevant data, including pre- and postoperative clinical characteristics, surgical management, and outcome.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Thirteen fenestrations of trapped fourth ventricles (FTFVs) were performed in 12 patients. In 6 patients with prominent arachnoid thickening, a stent was left from the opened fourth ventricle into the spinal subarachnoid space. One patient underwent a second FTFV 21 months after the initial procedure. No perioperative complications were encountered. All 12 patients (100%) showed clinical improvement after FTFV. Radiological improvement was seen in only 9 (75%) of the 12 cases. The follow-up period ranged from 2 to 9.5 years (mean 6.11 ± 2.3 years) after FTFV.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Fenestration of a TFV via craniotomy is a safe and effective option with a very good long-term outcome and low rate of morbidity.</jats:p></jats:sec>

Postulating the concept of compensated trapped fourth ventricle: a case-based demonstration with long-term clinicoradiological follow-up

“…The diagnostic and treatment dilemma is to differentiate between a "true" symptomatic TFV and other conditions associated with a large fourth ventricle. This dilemma is especially significant when attempting to identify those patients who may potentially benefit from surgery, as opposed to those patients with a well-compensated process wherein ventricular dilation terminates spontaneously with normal intracranial pressure, at which point it may be termed "compensated" or "arrested" hydrocephalus [3][4][5][6]. Schick and Matson reported that this spontaneous termination occurs in 10-15% of cases of supratentorial hydrocephalus [7].…”

Cranio-cervical decompression and expansile duroplasty for isolated fourth ventricle in a patient with Chiari II malformation

“…23 Craniectomy or craniotomy was performed, the arachnoid was opened widely at the gutters bilaterally, and the dura was closed either primarily or with a periosteal graft. A stent was placed from the fourth ventricle to the spinal subarachnoid space where the arachnoid was very thick and the fourth ventricle opening was small.…”

Descending transtentorial herniation, a rare complication of the treatment of trapped fourth ventricle: case report

“…The main treatment options consist of microsurgical fenestration through a posterior fossa craniotomy/craniectomy with or without placement of a stent to the spinal subarachnoid space, to achieve a diversion of CSF, or a fourth ventricle shunt, either separate or connected via a Y-shaped connector with a supratentorial ventricular catheter. 4,15,21,25,27 The advent and recent evolution of endoscopy has introduced new options in the treatment of this condition. In fact, an internal CSF diversion channel for trapped fourth ventricle may be achieved with aqueductoplasty, with or without aqueductal stent placement, or by fenestration of the superior medullary velum.…”