Endoscopic transaqueductal or interventricular stent placement for the treatment of isolated fourth ventricle and pre-isolated fourth ventricle

Transcerebellar ventriculoperitoneal shunt for management of presumed arachnoid diverticulum in the fourth ventricle of a dog

OBJECTIVE

To describe the approach for placement of a transcerebellar fourth ventriculoperitoneal shunt for management of presumed fourth ventricle arachnoid diverticulum and secondary obstructive hydrocephalus of a dog. To describe the outcome of this procedure.

STUDY DESIGN

Case report.

ANIMALS

Male entire English springer spaniel, 3 years 9 months of age.

METHODS

The dog was initially presented for management of acute, progressive, and multifocal brainstem and forebrain dysfunction. Magnetic resonance imaging revealed internal obstructive hypertensive hydrocephalus. The dog was managed via ventriculoperitoneal shunting from the left lateral ventricle and made an excellent recovery. The dog acutely deteriorated 18 months after initial discharge and follow-up magnetic resonance imaging confirmed the ventricular shunt remained in situ with normal-sized lateral ventricles but revealed a cystlike lesion within the fourth ventricle, presumed to be a fourth ventricle arachnoid diverticulum. The diverticulum was causing mass effect and resultant compression of adjacent neuroparenchyma. A second ventriculoperitoneal shunt was subsequently placed into the fourth ventricle via the caudal cranial fossa and cerebellum. This was attached to a three-way connector, to which the existing shunt (within the left lateral ventricle) was also attached, and then secured to the existing medium-pressure valve.

RESULTS

Postoperatively, the dog immediately developed mild vestibular-cerebellar ataxia, with a marked improvement after 3 months. There were no shunt-associated complications. Long-term follow up at 40 months after the second surgical procedure revealed a normal neurological examination.

CONCLUSION

Transcerebellar ventriculoperitoneal shunt placement for treatment of a presumed fourth ventricle arachnoid diverticulum was performed and was associated with a favorable long-term outcome.

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.

Radiologic and clinical outcome of isolated fourth ventricle following post-hemorrhagic hydrocephalus in children

PURPOSE

Few studies report radiologic and clinical outcome of post-hemorrhagic isolated fourth ventricle (IFV) with focus on surgical versus conservative management in neonates and children. Our aim is to investigate differences in radiological and clinical findings of IFV between patients who had surgical intervention versus patients who were treated conservatively.

METHODS

A retrospective analysis of patients diagnosed with IFV was performed. Data included demographics, clinical exam findings, surgical history, and imaging findings (dilated FV extent, supratentorial ventricle dilation, brainstem and cerebellar deformity, tectal plate elevation, basal cistern and cerebellar hemisphere effacement, posterior fossa upward/downward herniation).

RESULTS

Sixty-four (30 females) patients were included. Prematurity was 94% with 90% being < 28 weeks of gestation. Mean age at first ventricular shunt was 3.6 (range 1-19); at diagnosis of IFV, post-lateral ventricular shunting was 26.2 (1-173) months. Conservatively treated patients were 87.5% versus 12.5% treated with FV shunt/endoscopic fenestration. Severe FV dilation (41%), severe deformity of brainstem (39%) and cerebellum (47%) were noted at initial diagnosis and stable findings (34%, 47%, and 52%, respectively) were seen at last follow-up imaging. FV dilation (p = 0.0001) and upward herniation (p = 0.01) showed significant differences between surgery versus conservative management. No other radiologic or clinical outcome parameters were different between two groups.

CONCLUSION

Only radiologic outcome results showed stable or normal FV dilation and stable or decreased upward herniation in the surgically treated group.

The entity of the trapped fourth ventricle: A review of its history, pathophysiology, and treatment options

An isolated or trapped fourth ventricle is a relatively rare, although serious, adverse effect of hemorrhagic, infectious, or inflammatory processes that involve the central nervous system. This entity usually occurs after successful shunting of the lateral ventricles and may become clinically evident with the development of delayed clinical deterioration. This decline of the neurological status of the patient is evident after an initial period of improvement of the relevant symptoms. Surgical treatment options include cerebrospinal fluid shunting procedures, along with open surgical and endoscopic approaches. Complications related to its management are common and are related with obstruction of the fourth ventricular catheter, along with cranial nerve or brainstem dysfunction. We used the keywords: "isolated fourth ventricle," and "trapped fourth ventricle," in PubMed^® and Web of Science^®. Treatment of the trapped fourth ventricle remains a surgical challenge, although the neurosurgical treatment armamentarium has broadened. However, prompt recognition of the clinical and neurological findings that accompany any individual patient, in conjunction with the relevant imaging findings, is mandatory to organize our treatment plan on an individual basis. The current experience suggests that any individual intervention plan should be mainly based on the underlying pathological substrate of hydrocephalus. This could help us to preserve the patient's life, on an emergent basis, as well as to ensure an uneventful neurological outcome, maintaining at least the preexisting level of neurological function.

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

BACKGROUND

Endoscopic aqueductoplasty with aqueductal stenting is an effective surgical procedure for the treatment of isolated fourth ventricle (IFV). Due to the rarity of the underlying pathology, it can be considered a rare procedure that can be performed with different surgical techniques and approaches.

OBJECTIVES

To assess long-term functioning of permanent aqueductal stents implanted in children affected by hydrocephalus and IFV and to describe some variations of the same procedure.

METHODS

We reviewed retrospectively all the patients presenting at our institution in the years 1999-2019 for symptoms of isolated fourth ventricle who underwent a surgical procedure of endoscopic aqueductoplasty and/or aqueductal stent. Surgical reports, radiological images, and surgical videos were retrospectively analyzed.

RESULTS

Thirty-three patients with symptomatic isolated fourth ventricle (IFV) underwent fifty (50) neuroendoscopic procedures in the period observed. The median age of the patients at the time of first surgery was 7 months, with 22 premature babies. In twenty-nine patients (87.8%), a precoronal approach was performed, while four patients received a suboccipital burr hole. Ten patients were never reoperated since. Twenty-three patients underwent further surgeries: a new aqueductoplasty with aqueductal stent was performed in 13 cases. The remaining 10 patients required a combination of other procedures for management of hydrocephalus. Long-term follow-up showed a permanent stent functioning rate of 87% at 2 years and 73% at 4 years, remaining stable afterwards at very long term (20 years).

CONCLUSION

Endoscopic aqueductoplasty and stenting is a reliable procedure in the long-term management of isolated fourth ventricle.

Proposed radiological score for the evaluation of isolated fourth ventricle treated by endoscopic aqueductoplasty

PURPOSE

Evidence supporting the effectiveness of endoscopic aqueductoplasty (EA) for the treatment of isolated fourth ventricle (IFV) is limited to small surgical series of cases. Additionally, studies adopted different radiological outcome criteria, which makes it difficult to compare outcomes accurately. Thus, we aimed to develop a radiological score (RS) as an alternative assessment method for EA.

METHODS

The cases of 20 consecutive pediatric patients harboring IFV and treated by EA were retrospectively reviewed. Clinical data and pre- and 1-year postoperative brain images were analyzed. The RS was based on the enlargement of the fourth ventricle and deformation of the cerebellum and brainstem. After randomization, three experts, blinded to patient outcomes, analyzed the brain images and established a consensus for the values of the score. Outcomes were validated by comparing the maximum anteroposterior distance of the fourth ventricle using the RS, pediatric functional status score, and clinical symptoms.

RESULTS

The RS was strongly correlated with the anteroposterior distance of the fourth ventricle (Pearson's coefficient = 0.78), and the mean RS dropped from 6.15 to 3.90 (p < 0.001) 1 year after EA. Upward extension (p = 0.021) and brainstem deformation (p = 0.010) were the most significant improved features. There was agreement among RS and symptom improvement in 16 children (80%) and the pediatric functional status score in 14 children (70%).

CONCLUSION

In this study, the proposed radiological score proved to be an accurate tool for the evaluation of IFV treatment with EA.

Endoscopic aqueductal stenting in the management of pediatric hydrocephalus

OBJECTIVE

Pediatric patients with long-term shunts may experience specific complications related to the segregation of the supra- and infratentorial spaces along with different pressure regimens, leading to either mesencephalic syndromes during shunt dysfunction or isolated fourth ventricle (IFV). An accepted treatment to reestablish normal CSF pathways and reequilibrate the transtentorial pressures is endoscopic aqueductal stenting (EAS) to avoid restenosis. In the present paper, the authors studied children treated with EAS during the last decade for both IFV and obstructive hydrocephalus, evaluated its impact on the course of the disease, and identified prognostic factors for EAS success.

METHODS

A noninterventional retrospective study of routinely acquired data was performed, including all hydrocephalic children undergoing EAS between 2011 and 2019 at Hôpital Necker, Paris, France. The following variables were analyzed: etiology of hydrocephalus; number of surgeries before and after stent placement; indication for EAS; type of stent connection (i.e., connected or not to a ventriculoperitoneal shunt); and the stent position. Stent failure was defined as the need to perform further shunt revision. Univariate and multivariate analyses were run to identify factors associated with stent failure.

RESULTS

Seventeen patients with a mean age at stent placement of 6 years (SD 6.5 years, range 1 month-18 years) and with a mean follow-up after EAS of 47.5 months (SD 33.7 months, range 5-120 months) were included in the analysis. The etiology of hydrocephalus was as follows: obstructive tumoral (41%), posthemorrhagic (35%), postinfectious (12%), and dysraphism related (12%). The indication for EAS was IFV (47%), rostral midbrain dysfunction syndrome (35%), prevention of secondary aqueductal stenosis after debulking surgery (12%), or primary aqueductal stenosis (6%). No transient or permanent neurological deficits related to the procedure were observed. After EAS, 10 patients did not require further surgeries (59%), and for the others the number of hydrocephalus-related surgeries significantly decreased after stenting. In univariate analysis posthemorrhagic etiology and prevention of aqueductal stenosis were identified as predictors of a good outcome, whereas in multivariate analysis posthemorrhagic hydrocephalus was found to predict a favorable outcome.

CONCLUSIONS

The results confirm EAS as a first-line treatment for IFV and suggest its efficacy in changing the history of hydrocephalic patients who have undergone multiple operations and who experience rostral midbrain dysfunction syndrome, as well as efficacy in the prevention of aqueductal stenosis in selected cases of obstructive tumoral hydrocephalus.

Endoscopic Treatment Strategy for a Disproportionately Large Communicating Fourth Ventricle: Case Series and Literature Review

An isolated fourth ventricle (IFV) is characterized by fourth ventricular dilation due to obstruction of its inlet and outlet. A disproportionately large communicating fourth ventricle (DLCFV) is a rare subtype of IFV, characterized by dilation of the fourth ventricle, regardless of the size of the lateral ventricles, with no apparent obstruction of the cerebral aqueduct. To our knowledge, this is the first case series describing endoscopic diagnosis and treatment strategy for DLCFV. We retrospectively reviewed six cases of DLCFV in which endoscopic surgery was performed at our institution and affiliated facilities between June 2013 and March 2017. DLCFV was diagnosed using radiographic imaging and intraoperative endoscopy. We also conducted a PubMed search and included only original studies related to DLCFV treatment written in English in our review of the literature. Endoscopic third ventriculostomy (ETV) was performed in all patients. Additional endoscope-assisted placement of a fourth ventriculoperitoneal (VP) shunt was performed in two patients who could not be managed with ETV alone because of severe adhesion of the interpeduncular cistern due to subarachnoid hemorrhage (SAH). The patients' symptoms and the size of the fourth ventricle improved with surgical treatment, without complications. Endoscopic surgery for DLCFV appears to be a safe and effective treatment. Based on our treatment strategy, ETV is the first-line treatment for DLCFV. Endoscope-assisted placement of the fourth VP shunt can be treatment for severe adhesion of the interpeduncular cistern.

Disproportionately large communicating fourth ventricle: two case reports

Background

Management of the disproportionately large communicating fourth ventricle is still problematic.

Case presentation

Two cases of disproportionately large communicating fourth ventricle were treated successfully. One was a case of a 51-year-old Han Chinese woman with a complaint of headache and dizziness of 1 year’s duration. Magnetic resonance imaging (MRI) demonstrated hydrocephalus with a disproportionately large fourth ventricle. She underwent a ventriculo-peritoneal shunt of the right lateral ventricle. Her symptoms were relieved totally. Five years later, magnetic resonance imaging showed she had a normal ventricular system. The other case was a 24-year-old Han Chinese man with a 2-month history of headache and dizziness accompanied by progressive loss of bilateral vision. Magnetic resonance imaging revealed hydrocephalus with a disproportionately large fourth ventricle, crowded posterior cranial fossa, and syringomyelia extending from C1 to C5. He underwent suboccipital and C1 decompression and duraplasty. Shortly after the surgery, his symptoms were relieved completely, the syringomyelia completely disappeared, and the fourth ventricle became significantly smaller.

Conclusions

The management of the disproportionately large communicating fourth ventricle should be individualized. If it coexists with crowded posterior cranial fossa or syringomyelia, posterior fossa decompression could be an option for initial management. If there is no sign of crowded posterior cranial fossa or syringomyelia, shunt of the lateral ventricles might be the first choice.

Hydrocephalus in children

Imaging of hydrocephalus in utero, in infants and children is critically dependent on an understanding of the pathophysiology and treatment options for this condition in this age spectrum. For this reason, this chapter deals not only with the imaging modalities used to study hydrocephalus and how they are applied but also reviews key aspects of the pathophysiology and treatment of hydrocephalus in children. Imaging techniques to establish the diagnosis of chronic hydrocephalus fall into two categories: (1) tracer-type techniques that require an injection and observation of the transit of an injected substance through the ventricular system or subarachnoid space and (2) cross-sectional imaging, which allows for direct visualization of a point of obstruction within the ventricular system or subarachnoid space. For cross-sectional imaging, both magnetic resonance imaging (MRI) and computed tomography can be used, but MRI is usually preferred. Nomenclature has obscured the description of imaging findings in hydrocephalus. We suggest that most hydrocephalus is obstructive and propose to designate ventriculomegaly, the condition in which the ventricles are large on imaging, but there is no true obstruction to the outflow of cerebrospinal fluid.

Predictors of Outcome Following Cerebral Aqueductoplasty: An Individual Participant Data Meta-analysis

BACKGROUND

The evidence supporting the efficacy and safety of cerebral aqueductoplasty (CA) is limited to small surgical series.

OBJECTIVE

To perform an individual participant data meta-analysis to determine the efficacy and safety of CA and to determine the effect of patient's age, etiology, surgical approach, and use of stent on success.

METHODS

Electronic databases (MEDLINE, EMBASE, and CINAHL) were searched with no language or date restrictions to identify cohort studies of consecutive participants undergoing CA (without concomitant endoscopic third ventriculostomy or cerebrospinal fluid [CSF] shunt) that reported outcome. Outcome was defined as the time elapsed from the index operation until a second procedure was performed for CSF diversion.

RESULTS

Of 146 citations, 14 articles reporting on 137 participants were eligible. One hundred three participants (75%) did not require a second CSF diversion procedure. The mean duration until repeat CSF diversion procedure was 121.6 months (95% confidence interval [CI], 102.2-141.0). In multivariate analysis, older age at surgery (hazard ratio [HR], 0.43; 95% CI, 0.21-0.88; P = .020), congenital etiology (HR, 0.18; 95% CI, 0.04-0.85; P = .030), and use of stent (HR, 0.30; 95% CI, 0.13-0.70; P = .006) were independent predictors of good outcome. Morbidity, mainly ophthalmoparesis and hemorrhage, was experienced in 22% of participants.

CONCLUSION

Small retrospective cohort studies are inherently prone to biases, some of which are overcome through the use of individual participant data. The best available evidence suggests that CA is an effective procedure with a moderate morbidity profile. Older age at surgery, congenital etiology, and use of stent predict a good outcome with respect to delaying the requirement for a second CSF diversion procedure.

Frequency and long-term follow-up of trapped fourth ventricle following neonatal posthemorrhagic hydrocephalus

OBJECTIVE Intraventricular hemorrhage (IVH) is a common complication of premature neonates with small birth weight, which often leads to hydrocephalus and treatment with ventriculoperitoneal (VP) shunting procedures. Trapped fourth ventricle (TFV) can be a devastating consequence of the subsequent occlusion of the cerebral aqueduct and foramina of Luschka and Magendie. METHODS The authors retrospectively reviewed 8 consecutive cases involving pediatric patients with TFV following VP shunting for IVH due to prematurity between 2003 and 2012. The patients ranged in gestational age from 23.0 to 32.0 weeks, with an average age at first shunting procedure of 6.1 weeks (range 3.1-12.7 weeks). Three patients were managed with surgery. Patients received long-term radiographic (mean 7.1 years; range 3.4-12.2 years) and clinical (mean 7.8 years; range 4.6-12.2 years) follow-up. RESULTS The frequency of TFV following VP shunting for neonatal posthemorrhagic hydrocephalus was found to be 15.4%. Three (37.5%) patients presented with symptoms of posterior fossa compression and were treated surgically. All of these patients showed signs of radiographic improvement with stable or improved clinical examinations during postoperative follow-up. Of the 5 patients treated conservatively, 80% experienced stable ventricular size and 1 patient experienced a slight increase (3 mm) on imaging. All of the nonsurgical patients showed stable to improved clinical examinations over the follow-up period. CONCLUSIONS The frequency of TFV among premature IVH patients is relatively high. Most patients with TFV are asymptomatic at presentation and can be managed without surgery. Symptomatic patients may be treated surgically for decompression of the fourth ventricle.

Aqueductal stenting with an intra-catheter endoscope--a technical note

INTRODUCTION

Aqueductoplasty as well as aqueductal stenting is an accepted therapy option in short-segment aqueductal stenosis and isolated fourth ventricle. Over the years, different techniques with only slight modifications by using a conventional neuroendoscope with a working sheath to introduce different instruments have been presented. In summary, the use of Fogarty balloon catheters or flexible endoscopes to pass the narrowed aqueduct is recommended.

METHODS

This technical report describes a substantially new technique for this purpose. Six patients underwent aqueductal stenting with a new intracatheter endoscope.

RESULTS

Aqueductal stenting was possible in 4 out of 6 cases. No complications occurred. Handling of this new technique was good and easy without a prolonged learning curve. All four stents did work appropriately, and the procedure was considered to be successful. Of the two failures, the technique was abandoned and endoscopic third ventriculostomy (ETV) was performed in one. In the other case, suboccipital shunting was done.

CONCLUSION

This technical report describes a substantially new technique for aqueductal stenting. The combination of an intracatheter miniature endoscope and a prepared ventricular catheter enables careful and elegant aqueductal stenting. Large or flexible endoscopes, balloons, or special instruments to place a stent have become completely obsolete in selected cases.

Acutely Trapped Ventricle: Clinical Significance and Benefit from Surgical Decompression

BACKGROUND

Focal ventricular obstruction--trapped ventricle--results in cerebrospinal fluid accumulation, mass effect and possible clinical deterioration. There are no systematic studies on the benefit of surgical decompression in adults.

METHODS

We reviewed patients admitted with acutely trapped ventricle on brain imaging to assess their prognosis and the effect of surgical intervention on 30-day mortality.

RESULTS

Of the 392 patients with trapped ventricle, the most common causes were brain tumor (45%), intracerebral hemorrhage (ICH) (20%), and subdural hematoma (SDH) (14%). Lateral ventricle trapping accounted for 97% of cases. Two hundred and twenty-one patients (56%) received a surgical intervention for trapped ventricle or its causes; 126 (83%) were treated with craniotomy, 26 (17%) with craniectomy, 30 (14%) with external ventricular drain (EVD) alone, 23 (10%) with ventriculoperitoneal shunt alone, and 16 (7%) with endoscopic fenestration of the septum pellucidum. Surgical intervention was associated with mortality reduction from 95% (n = 54) to 48% (n = 11) in the ICH group, from 47% (n = 27) to 12% (n = 15) in the tumor group and from 90% (n = 18) to 20% (n = 7) in the SDH group (p < 0.001 for all comparisons). Univariate logistic analysis showed that surgical intervention and tumor etiology were associated with decreased mortality while age, ICH etiology, intraventricular hemorrhage, midline shift, and anticoagulation were associated with increased mortality. On multivariate logistic regression, surgical intervention remained associated with decreased mortality (p < 0.0001; OR 0.20, 95% CI 0.09-0.42). On subgroup analysis of the ICH cohort, surgical intervention was also associated with decreased mortality (p = 0.028).

CONCLUSIONS

Neurosurgical intervention for decompression in patients with trapped ventricle can have a measurable beneficial effect on early mortality.