Endoscopic aqueductoplasty and stenting in the treatment of isolated fourth ventricle in children: 20-year institutional experience

Delayed symptomatic TFV in neonatal posthemorrhagic hydrocephalus-pathophysiology and therapeutic strategy: A case report and review of the literature

INTRODUCTION

Trapped fourth ventricle (TFV), which is a rare neurosurgical condition with multifactorial etiology, requires a prompt diagnosis and appropriate therapeutic method selection. We report a case of post-hemorrhagic hydrocephalus and TFV incited/worsened by prematurity, sepsis, acute respiratory distress syndrome (ARDS), mechanical ventilation, and concomitant fourth ventricle outlets stenosis; which displayed a delayed onset. This article addresses the proposed pathophysiology and the clinical importance of appropriate therapeutic strategies with a mini-review of the literature.

CASE PRESENTATION

We encountered a case involving a premature Asian male newborn with sepsis and posthemorrhagic hydrocephalus who required ventriculoperitoneal shunt surgery. However, after three years, the baby was diagnosed with a trapped fourth ventricle and subsequently underwent retrograde endoscopic surgery with stent insertion.

DISCUSSION

TFV is traditionally known as a complication of lateral ventricle shunting. However, in rare cases such as our neonate patient, it develops as a consequence of multiple pathophysiological processes including ventricular system inflammation along with associated anatomic and physiologic alterations, which necessitates prompt diagnosis and a case-specific therapeutic strategy.

CONCLUSION

Understanding the multifactorial pathophysiological mechanisms leading to the development of TFV is crucial. The presence of comorbidities such as prematurity, neonatal sepsis, and ARDS increased the risk of intraventricular hemorrhage and subsequent inflammation and further exacerbated obstructions in cerebrospinal fluid pathways. When posthemorrhagic TFV is accompanied by collapsed lateral ventricles, the optimal treatment approach is retrograde endoscopic fenestration with stent insertion. This treatment option has proven effective in alleviating the condition and restoring proper cerebrospinal fluid flow.

Endoscopic transaqueductal stent placement for tumor-related aqueductal compression in pediatric patients: surgical consideration, technique, and results

PURPOSE

Endoscopic transaqueductal stenting has become a well-accepted treatment option for a selected small subset of aqueductal stenosis-related obstructive hydrocephalus. However, transaqueductal stenting poses unique challenges and risks which requires critical consideration. This report discusses the clinical experiences with transaqueductal stenting for periaqueductal tumor-related aqueductal stenosis focusing on pediatric patients.

METHODS

A retrospective analysis of all patients undergoing endoscopic TAS from 01/1993 to 01/2022 in the author's departments was performed. Demographic, clinical, radiological, and intraoperative endoscopic data were evaluated. All patients with AS-related occlusive hydrocephalus that was treated with TAS were analyzed and prospectively followed. Special attention has been given to providing insights into indications, surgical technique, and limitations.

RESULTS

Out of 28 endoscopic transaqueductal endoscopis stenting procedures, five procedures were performed on periaqueductal tumor-related obstructive hydrocephalus, two children and three adult patients. CSF pathway was obstructed by tumor located in the aqueduct in 2, by tumor in the thalamus/mesencephalon in 1, by a tumor within the third ventricle in 1, and by a tumor of the lamina tecti in 1. Simultaneously with transaqueductal stenting, 2 endoscopic third ventriculostomies (ETV), 3 tumor biopsies, and 1 tumor resection were performed. Postoperative complications included the following: CSF fistula (1 case), and asymptomatic fornix contusion (1 case). A working aqueductal stent was achieved in all cases based on clinical follow-up evaluation. Postoperatively, all patients showed improvement or resolution of their symptoms. The mean follow-up period was 25.2 months (range, 1-108 months). One patient died due to tumor progression during early follow-up. No stent migration was seen.

CONCLUSION

Endoscopic third ventriculostomy remains the gold standard for treatment of CSF circulation obstructions with lesions in the posterior third ventricle and aqueduct. Transaqueductal stenting for periaqueductal tumor-related aqueductal compression is technically feasible. However, because of the potential high risks and subtle advantages compared with ETV transaqueductal stenting, it might be indicated in a small subset of well-selected patients if alternative treatment options are not at hand.

Endoscopic fenestration of the superior medullary velum for the treatment of a trapped fourth ventricle-technical note

A trapped fourth ventricle is a clinic-radiological entity characterised by progressive neurological symptoms due to an enlargement of the fourth ventricle secondary to obstruction to its outflow. This condition is most commonly observed in ex-preterm patients shunted for a post-haemorrhagic or post-infective hydrocephalus. Until the introduction of endoscopic aqueductoplasty and stent placement, through a supratentorial or an infratentorial approach, treatment of trapped fourth ventricle entailed high rates of complications, repeated procedures and consequent morbidity. We describe the first case of successful treatment of trapped fourth ventricle by fenestration of superior medullary velum through an infratentorial approach in a 20-month-old child with a functional supratentorial ventriculoperitoneal shunt and an aqueductal anatomy not favourable for stenting. To the best of our knowledge, this is the first reported case of utilisation of this technique in a patient with a trapped fourth ventricle, and we wish to highlight this new alternative approach in cases where conventional aqueductoplasty and stenting may not be feasible.

Trapped fourth ventricle: to stent, shunt, or fenestrate-a systematic review and individual patient data meta-analysis

Trapped or isolated fourth ventricle (TFV) is a rare but critical neurosurgical condition, mostly occurring in pediatric patients, caused by a blockage of the in- and outlets of the fourth ventricle. The purpose of this study is to review all available data on the treatment options of TFV and to compare their safety, efficacy, and durability. MEDLINE, Embase, and Google Scholar were searched from inception to September 13, 2022, for prospective or retrospective cohorts, case-control studies, case series or case reports, reporting detailing outcomes of TFV patients, treated with an endoscopic-, microsurgical-, shunt placement,- or hybrid approaches to TFV. All authors were contacted to provide individual patient data. Eighty-seven articles (314 patients) were included in the individual patient data meta-analysis (IPD) and 9 (151 patients) in the cohort meta-analysis. The IPD revealed that primary endoscopic (aOR 0.21; [95% CI 0.08-0.57]) and microsurgical interventions (aOR 0.21; [95% CI 0.05-0.82]) were associated with a significantly lower revision rate, compared to shunt placement, when adjusted for confounders. Endoscopy was also associated with a significantly higher rate of clinical improvement (aOR 4.56; [95% CI 1.2-18]). The meta-analysis revealed no significant difference in revision rate between the endoscopic (0.33 [95% CI 0.0-0.52]) and shunt group (0.44 [95% CI 0.0-1.0]). Endoscopy should be considered as the first-line treatment of TFV due to its superior efficacy, durability, and similar safety, compared to shunt placement and its minimally invasive nature. Microsurgery should be considered as a second treatment option, due to its similar clinical outcomes and revision rate as endoscopy, but it is more invasive in nature.

FOURTH VENTRICLE ENTRAPMENT MANAGEMENT AND ITS OUTCOMES: CASE-SERIES FROM A SINGLE NEUROSURGERY CENTER

This case-series aims to report the elaborate management of FVEs in our center and their outcome. Data from 2017 to 2022 were retrospectively collected. We reviewed patient's demography, clinical findings, radiology results, operative procedures, and complications after surgery. Five patients with FVE diagnosis underwent neurosurgical procedures. The procedures include VP shunt, endoscopic cyst fenestration and fourth ventricle peritoneal shunt (FVPS). Out of five patients, 3 had favorable outcomes, 1 deceased, and 1 patient were still hospitalized. The underlying diseases varied from hemorrhage, cyst, infection, congenital, and neoplasm. FVE etiologies range from congenital to intraventricular hemorrhage complications and infection. VPS, FVPS, and endoscopic treatment with stenting or fenestration are surgical options for treating FVE patients. CSF diversion using shunt device is the simplest procedure. Patients with FVE in general have favorable outcome after CSF diversion of any method.

Trapped Fourth Ventricle: Pathophysiology, History and Treatment Strategies

Trapped fourth ventricle is a clinic-radiological entity characterised by progressive neurological symptoms due to enlargement and dilatation of fourth ventricle secondary to obstruction to its outflow. There are several causative mechanisms for the development of trapped fourth ventricle, including previous haemorrhage, infection or inflammatory processes. However, this condition is most commonly observed in ex preterm paediatric patients shunted for a post-haemorrhagic or post-infective hydrocephalus. Until the introduction of endoscopic aqueductoplasty and stent placement, treatment of trapped fourth ventricle was associated with high rates of reoperation and complications resulting in morbidity. With the advent of new endoscopic techniques, supratentorial and infratentorial approaches for aqueductoplasty and stent insertion have revolutionised the treatment of trapped fourth ventricle. Fourth ventricular fenestration and direct shunting remain viable options in cases where aqueduct anatomy and length of obstruction is not surgically favourable for endoscopic approaches. In this book chapter, we explore the background, historical developments,$ and surgical treatment strategies in the management of this challenging condition.

Endoscopic-Assisted Trans-Lateral Ventricular Transchoroidal Fissure Trans-Aqueductal Approach for Evacuation of Severe Intraventricular Hemorrhage

BACKGROUND

Intraventricular hemorrhage (IVH) is one of the most fatal types of intracerebral hemorrhage (ICH), especially when the third and the fourth ventricles are involved. The use of external ventricular drainage is limited for evacuation of hemorrhage in the lateral ventricles. Endoscopic surgery can provide visualized evacuation of the hemorrhage in the lateral and third ventricles. However, it is usually challenging to access the fourth ventricle using a routine endoscopic approach.

METHODS

We have reported 3 cases of severe IVH with cast fourth ventricles treated using an endoscopic-assisted trans-lateral ventricular transchoroidal fissure trans-aqueductal approach.

RESULTS

The average preoperative Graeb score was 11, and the average IVH volume was 75.12 mL. The IVH evacuation rate was 97.5%-100%. The average Glasgow coma scale score had increased to 12 at discharge from 6.6 at admission. At 3 months after surgery, the average modified Rankin scale score was 3. No cerebrospinal fluid shunt had been required and no surgery-related complication had occurred in any patient.

CONCLUSIONS

Our results have shown that the endoscopic-assisted trans-lateral ventricular transchoroidal fissure trans-aqueductal approach is a feasible and safe endoscopic option that can achieve one-off complete removal of clots in all 4 ventricles in patients with severe IVH.

Management of Complex Hydrocephalus

Background

Management of complex/multiloculated/septated hydrocephalus is challenging. Neuroendoscopy has been well-established when compared to multiple shunt placements in management of multiloculated hydrocephalus (MH). The main aim of neuroendoscopy is to convert multiple locules into a single locule and drain it by either third ventriculostomy or ventriculoperitoneal shunt.

Objective

The objective is to reduce the number of surgical procedures and improve the quality of life. Neuroendoscopy avoids multiple shunt placement and need for revision of shunt.

Methods

Literature review regarding natural history, pathogenesis, classification and management of complex/uni/multiloculated hydrocephalus was extensively done and our minimal experience with these cases has been taken into consideration.

Conclusion

Neuroendoscopy when combined with frameless neuronavigation is reliable, accurate, and extremely useful in maintaining orientation and localizing the appropriate fenestration site in MH where anatomical landmarks are grossly distorted.