The effect and evolution of patient selection on outcomes in endoscopic third ventriculostomy for hydrocephalus: A large-scale review of the literature

Outcomes of Endoscopic Third Ventriculostomy in Pediatric Patients With Hydrocephalus

Background

Endoscopic third ventriculostomy (ETV) is used to treat patients with obstructive hydrocephalus in infants. This study evaluated the postoperative outcomes of ETV among pediatric patients.

Methodology

A retrospective study was undertaken at the Mardan Medical Complex between June 2018 and June 2021. All pediatric patients who underwent the procedure of ETV in both the absence and presence of choroid plexus cauterization (CPC) at our center were included in the study. Using medical history data, a comprehensive survey questionnaire was designed. The findings and effects were evaluated either as a success or failure.

Results

A total of 90 cases were reviewed during the study. The rate of in-hospital mortality was 1.1% while the most commonly identified causes of hydrocephalus were myelomeningocele and aqueductal stenosis. A total of 39 (43.33%) patients had a successful surgery. In patients where hydrocephalus was secondary to aqueductal stenosis, the success rate was the highest, while the success rate was quite low for post-infectious hydrocephalus and intraventricular hemorrhage (p < 0.0001). The postoperative complication rate was 55.56% in our study. The rate of in-hospital mortality was 1.1%.

Conclusions

We found that the success rate of ETV was dependent upon factors such as the cause of hydrocephalus, type of hydrocephalus, and the age of the patient. Therefore, ETV is not suitable for all patients, and vigilance must be undertaken in selecting patients for the procedure. The rate of postoperative infections in our institution was alarmingly high which is a concerning matter for the institution.

Intratumoral Hemorrhage After Endoscopic Third Ventriculostomy for Obstructive Hydrocephalus Caused by Brain Tumors

BACKGROUND

Endoscopic third ventriculostomy (ETV) for obstructive hydrocephalus and endoscopic biopsy (EB) for intraventricular and paraventricular tumors are standard therapies because they are minimally invasive procedures. Although EB-associated hemorrhagic risk has been well documented, there have been only a few reports on hemorrhagic risk associated with ETV. We conducted a single-institution retrospective study on the incidence of hemorrhage secondary to EB and/or ETV.

METHODS

We retrospectively reviewed patient characteristics, procedure, pathological findings, and complications including hemorrhage of 100 patients with intraventricular and paraventricular tumors who underwent EB and/or ETV at our institution from 2000 to 2020.

RESULTS

EB/ETV combined surgery (combined group), EB-alone surgery (EB-alone group), and ETV-alone surgery (ETV-alone group) were performed in 44 (44%), 24 (24%), and 32 (32%) patients, respectively, and all procedures were successful. The rates of definitive and suggestive diagnoses in EB were 76.5% and 23.5%, respectively. Adverse events were observed in 6 patients. In the combined group, acute obstruction of the ETV stoma was observed in 1 patient and transient double vision was observed in 1 patient. Transient aqueductal stenosis/obstruction was observed in 2 patients in the EB-alone group. In the ETV-alone group, hemorrhage was observed in 2 patients; these patients developed intratumoral hemorrhage despite ETV-alone surgery. Subsequently, these 2 patients underwent tumor removal, and the histopathological diagnosis was atypical teratoid/rhabdoid tumor in both.

CONCLUSIONS

For obstructive hydrocephalus with atypical teratoid/rhabdoid tumor, physicians must be aware of the risk of postoperative intratumoral hemorrhage after performing ETV.

Endoscopic third ventriculostomy in the treatment of hydrocephalus: A 20-year retrospective analysis of 209 consecutive cases

Background

Endoscopic third ventriculostomy (ETV) has been shown to be a sufficient alternative to shunts in surgical treatment of obstructive hydrocephalus. Long-term failure, age limitations, and outcome by cause are some of the issues debated in literature. The objective of this article is to analyze the clinical success and failure of ETV and its main complications.

Methods

A total of 209 patients with hydrocephalus were submitted to ETV, including a mixed population of children and adults (from 0 to 59 years). Patients were divided into five groups: A - tumors, B - aqueductal stenosis, C - myelomeningocele, D - infection and hemorrhage, and E - arachnoid cyst. Variables were analyzed: age, ETV success rate, cerebrospinal fluid (CSF) fistula, mortality, and complications.

Results

The two main causes of hydrocephalus were tumors (44.9%) and aqueductal stenosis (25.3%). The overall success rate was of 82.8%, and patients in Group E had the highest rate 90.9%. Group A had a success rate of 89.3%, and Group B had a rate of 88.6%. The ETV success rate was significantly higher in patients older than 1 year (P < 0.001); the former also had a lower risk of CSF fistula (P < 0.0001). The overall mortality rate was 2.8%.

Conclusion

Better results were observed in the groups of patients with tumors, aqueductal stenosis, and arachnoid cysts, while those whose primary causes of hydrocephalus were myelomeningocele, infections, or bleeding had higher rates of failure after the procedure. This study demonstrated that age under 1 year and hydrocephalus caused by myelomeningocele, bleeding, and infection were considered independent risk factors of poor prognosis in ETV.

Endoscopic third ventriculostomy for pediatric tumor-associated hydrocephalus

OBJECTIVE

Surgical options for managing hydrocephalus secondary to CNS tumors have traditionally included ventriculoperitoneal shunting (VPS) when tumor resection or medical management alone are ineffective. Endoscopic third ventriculostomy (ETV) has emerged as an attractive treatment strategy for tumor-associated hydrocephalus because it offers a lower risk of infection and hardware-related complications; however, relatively little has been written on the topic of ETV specifically for the treatment of tumor-associated hydrocephalus. Here, the authors reviewed the existing literature on the use of ETV in the treatment of tumor-associated hydrocephalus, focusing on the frequency of ETV use and the failure rates in patients with hydrocephalus secondary to CNS tumor.

METHODS

The authors queried PubMed for the following terms: "endoscopic third ventriculostomy," "tumor," and "pediatric." Papers with only adult populations, case reports, and papers published before the year 2000 were excluded. The authors analyzed the etiology of hydrocephalus and failure rates after ETV, and they compared failure rates of ETV with those of VPS where reported.

RESULTS

Thirty-two studies with data on pediatric patients undergoing ETV for tumor-related hydrocephalus were analyzed. Tumors, particularly in the posterior fossa, were reported as the etiology of hydrocephalus in 38.6% of all ETVs performed (984 of 2547 ETVs, range 29%-55%). The ETV failure rate in tumor-related hydrocephalus ranged from 6% to 38.6%, and in the largest studies analyzed (> 100 patients), the ETV failure rate ranged from 10% to 38.6%. The pooled ETV failure rate was 18.3% (199 failures after 1087 procedures). The mean or median follow-up for ETV failure assessment ranged from 6 months to 8 years in these studies. Only 5 studies directly compared ETV with VPS for tumor-associated hydrocephalus, and they reported mixed results in regard to failure rate and time to failure. Overall failure rates appear similar for ETV and VPS over time, and the risk of infection appears to be lower in those patients undergoing ETV. The literature is mixed regarding the need for routine ETV before resection for posterior fossa tumors with associated hydrocephalus.

CONCLUSIONS

Treatment of tumor-related hydrocephalus with ETV is common and is warranted in select pediatric patient populations. Failure rates are overall similar to those of VPS for tumor-associated hydrocephalus.

Detailed Analysis of Hydrocephalus and Hindbrain Herniation After Prenatal and Postnatal Myelomeningocele Closure: Report From a Single Institution

BACKGROUND

The Management of Myelomeningocele Study (MOMS) demonstrated that fetal myelomeningocele (fMMC) closure results in improved hydrocephalus and hindbrain herniation when compared to postnatal closure.

OBJECTIVE

To report on the outcomes of a single institution's experience in the post-MOMS era, with regard to hydrocephalus absence and hindbrain herniation resolution.

METHODS

A single-center retrospective study of a subset of post-MOMS patients who underwent fetal/postnatal myelomeningocele closure was performed. Primary outcomes included cerebrospinal fluid (CSF) diversion status and hindbrain herniation resolution. Families were contacted via telephone for outcome information if care was transitioned to outside institutions. Univariate/multivariable analyses were performed using several prenatal and postnatal variables.

RESULTS

From January 2011 to May 2016, data were reviewed from families of 62 postnatal and 119 fMMC closure patients. In the postnatal group, 80.6% required CSF diversion compared to 38.7% fetal cases (P < .01). Hindbrain herniation resolution occurred in 81.5% fetal repairs compared to 32.6% postnatal (P < .01). In the fetal group, fetal/premature neonatal demise occurred in 6/119 (5.0%) patients. There was a 42.0% decrease (95% CI -55.2 to -28.8) and 48.9% increase (95% CI 33.7 to 64.1) in risk difference for CSF diversion and hindbrain herniation resolution, respectively, in the fetal group. On univariate analysis for both groups, prenatal atrial diameter, frontal-occipital horn ratio, and hindbrain herniation resolution were significantly associated with the absence of clinical hydrocephalus. The treatment of hydrocephalus was significantly delayed in the fetal group compared to the postnatal group (10 mo vs 13.8 d).

CONCLUSION

This study demonstrates the benefits of fMMC closure with regard to CSF dynamics.

Success and complication rates of endoscopic third ventriculostomy for tuberculous meningitis: a systematic review and meta-analysis

Because ventriculoperitoneal shunt (VPS) insertion for patients with hydrocephalus from tuberculous meningitis (TBM) can be complicated by shunt infection and malfunction, endoscopic third ventriculostomy (ETV) has been proposed as an alternative. The aim of this review was to determine the success, technical failure, and complication rates of ETV in TBM in a meta-analysis and determine which factors are predictive of outcome. The PubMed, Scopus, and CENTRAL databases were searched from inception to April 2020 for case series, cohort studies, or randomized controlled trials reporting success, technical failure, or complication rates. For studies with individual patient data available, logistic regression analysis was done to determine whether age, sex, clinical grade, and type of hydrocephalus on imaging was predictive of outcome. Eight studies with a total of 174 patients were included in the review. Using random-effects modeling, the pooled estimate of success rate was 59% (95% CI 50-68%), with low heterogeneity (I² = 30%). The technical failure and complication rates were 5% and 15%, respectively, but these variables had moderate heterogeneity. In 36 patients with individual patient data, a non-communicating type of hydrocephalus on imaging was associated with an odds ratio of 5.90 (95% CI 1.1-32.9, p = 0.043) for success. In summary, ETV for TBM had a pooled success rate of 59%, technical failure rate of 5%, and complication rate of 15%. An imaging finding of non-communicating hydrocephalus was associated with increased success. High-quality randomized, prospective studies using VPS insertion as control are needed to further define the role of ETV in TBM.

A Review of Common Endoscopic Intracranial Approaches

With the evolution of surgical techniques, endoscopy has emerged as a suitable alternative to many instances of more invasive methods. In this review article, we aim to discuss the endoscopic advancements, procedural details, indications, and outcomes of the most commonly practiced neuroendoscopic procedures. We have also summarized the uses, techniques, and challenges of neuroendoscopy in select neurosurgical pathologies.

Third ventricle floor bowing: a useful measurement to predict endoscopic third ventriculostomy success in infantile hydrocephalus

BACKGROUND

Preoperative judgment who will benefit from endoscopic third ventriculostomy (ETV) in infantile hydrocephalus remains controversial and no sufficient clue exists. Although ETV success score (ETVSS) is a useful scale in predicting ETV success in hydrocephalus, its efficacy in infants younger than 1 year old has been limited. This study aimed to verify the efficacy of a newly defined sign, "third ventricle floor bowing (TVFB)," in predicting ETV success in infantile hydrocephalus for the first time and discuss the mechanism of this sign and its clinical meanings.

METHODS

Between January 2013 and April 2018, hydrocephalic infants (age ≤ 12 months) with third ventricle floor bowing were treated endoscopically in the Department of Neurosurgery, West China Hospital. The medical records of these patients were reviewed. Additionally, we undertook a detailed review of the reported data on the treatment of infantile hydrocephalus with endoscopic third ventriculostomy (ETV).

RESULTS

A total of 42 infants underwent ETV alone in our institution, with a median age of 7.3 ± 3.8 months. Common etiologies included postinfectious (26.2%), arachnoid cyst (14.3%), aqueductal stenosis (11.9%), and congenital condition (11.9%). The complications included seizure (2.4%), CSF leak (2.4%), and subdural effusion (2.4%). During the average follow-up of 21.7 ± 13.1 months, the ETV success rate predicted by third ventricle floor bowing (TVFB) was 71.4%, which was higher than 6-month success rate predicted by the ETVSS (52.3%). However, it was difficult to reach statistical significance (P = 0.072) due to the limited sample size and further studies with larger sample size were needed.

CONCLUSIONS

Our study suggests TVFB can serve as a useful method for selecting ETV candidates in infantile hydrocephalus preoperatively. And we speculate that good ventricle compliance and pressure difference between the ventricle and subarachnoid space are essential elements in ensuring ETV success.

Anatomical characterization of the inferior petrosal sinus and adjacent cerebellopontine angle cistern for development of an endovascular transdural cerebrospinal fluid shunt

Background and purpose

We evaluated the inferior petrosal sinus (IPS) and adjacent cerebellopontine angle (CPA) cistern as a potential implantation site for a novel venous endovascular transdural CSF shunt concept to treat communicating hydrocephalus. We analyzed the dimensions of the IPS, CPA cistern, and distances to adjacent neurovascular structures.

Materials and methods

Gadolinium enhanced T1 weighted brain MRI datasets of 36 randomly selected patients, aged 20–80 years, were analyzed with three-dimensional multiplanar reconstruction to measure IPS diameter and length, CPA cistern depth, and IPS proximity to the vertebrobasilar arteries and brainstem. Statistical analysis was used to assess gender, sidedness, and age dependence.

Results

Mean IPS diameter ranged from 2.27 mm to 3.31 mm at three axial levels, with >90% larger than 1.46 mm. CPA cistern adjacent to the IPS exhibited a mean depth of 3.86 mm to 7.39 mm between the dura and brainstem at corresponding axial levels. There was no side dependence except for a longer distance from the IPS to the basilar artery on the left compared with the right (9.72 vs 7.28, P<0.019). Linear regression analysis showed that the distance from the IPS to the brainstem was statistically significantly increased with age (P<0.0002) and was greater in men, with little side variation (P=0.524).

Conclusion

Our results demonstrate sufficient CSF CPA cisternal space adjacent to the IPS and support the feasibility of an endovascular catheter delivered transdural implantable shunt. Such a device could serve to mimic the function of the arachnoid granulation by establishing a regulated path for CSF flow from the intracranial subarachnoid space to the venous system and provide a treatment for communicating hydrocephalus.

A New Optimal Marker to Evaluate the Effectiveness of Endoscopic Third Ventriculostomy During Operation: "Folding Sign"

OBJECTIVE

Endoscopic third ventriculostomy (ETV) remains the mainstay of treatment for noncommunicating hydrocephalus these days. However, there has been no adequate clue for the intraoperative assessment of ETV efficacy until now. This time, we propose a newly defined finding, "folding sign," which is visible and enables us to confirm penetration of both the third ventricle floor and the Liliequist membrane (LM) during operation. In this report, we describe consecutive ETV cases and discuss the mechanism of folding sign and its clinical meanings.

METHODS

A folding sign is a formation of a sequence of folds at the tectal region, which is easily detectable. A total of 30 patients with newly diagnosed hydrocephalus between October 2014 and February 2018 at Tokyo Women's Medical University were enrolled in our case series (age range, 3 months to 74 years). The difference between proportions was analyzed by the χ² method.

RESULTS

In all, 12 patients (40%) showed a folding sign: congenital hydrocephalus including aqueductal stenosis (AS) and isolated fourth ventricle in 4 patients, and brain tumor-associated noncommunicating hydrocephalus in 8 patients. Statistical analysis showed that the emergence of a folding sign was related to successful ETV, indicating it as an optimal intraoperative sign to assess the effectiveness of this procedure (P = 0.0298).

CONCLUSION

The folding sign is a newly defined sign to predict the success of ETV during operation. This optimal finding appears only when the LM is sufficiently opened; therefore, it could be a good candidate for an intraoperative assessment tool.

Update on Endoscopic Third Ventriculostomy in Children

Endoscopic third ventriculostomy (ETV) provides a physiological restoration of cerebrospinal fluid and a shunt-free option for hydrocephalus children. Continuous developments in techniques and instruments have improved ETV as the first-line treatment. This paper focuses on the recent advances in surgical techniques, instruments, predictive models, imaging tools, and new cohort studies. The efficacy, safety, indications, and remaining challenges of ETV are discussed. More patients undergo ETV with a better outcome, identifying a new era of hydrocephalus treatment. Deeper understanding of ETV will improve a better shunt-free survival for pediatric hydrocephalus patients.