Assessment of the influence of operative factors in the success of endoscopic third ventriculostomy in children

Ventricular Anatomical Differences-A Different Perspective on Endoscopic Treatment of Pediatric Hydrocephalus: Anomalies, Variations, and Deformations

OBJECTIVE

Endoscopic management of pediatric hydrocephalus is always challenging because of the different anatomical structure of the ventricles. The aim of this study is to document the endoscopic anatomy of the ventricular system and to show the variations and deformations.

METHODS

The study included 84 children who underwent endoscopic surgery for the treatment of hydrocephalus in the department of neurosurgery between 2017 and 2022. All preoperative and postoperative radiological images and intraoperative video recordings were retrospectively analyzed. Anatomy of the lateral ventricles and the third ventricle, variations, and deformations were detected and evaluated in detail.

RESULTS

The mean age of the patients was 7.6 months. Myelomeningocele-encephalocele-associated hydrocephalus was the most common cause of hydrocephalus (38%), followed by postventriculitis in 21%, posthemorrhagic in 21%, and obstructive causes in 20% of cases, respectively. Endoscopic anomaly/variation or deformation was detected in 83% of all cases. Based on the preoperative radiological images, septum pellucidum anomaly/variation or deformation was the most common radiological finding in 64% of the cases. Lateral ventricle anomaly/variation or deformation was noted in 62% of the cases, and third ventricle anomaly/variation or deformation was observed as a radiological finding in 27% of the cases.

CONCLUSIONS

The compliance of the brain deteriorates with increasing intracranial pressure in pediatric hydrocephalus and the intraventricular anatomical structures differ from the normal anatomy. Developmental anomalies of the ventricle are also significant and since all these variations are often unpredictable on preoperative imaging, awareness of endoscopic anatomy, variations, and deformations will improve operative safety in children.

Compare the safety and efficacy of endoscopic third ventriculostomy and ventriculoperitoneal shunt placement in infants and children with hydrocephalus: a systematic review and meta-analysis

PURPOSE

Endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt placement are two surgical options used for treatment of non-communicating hydrocephalus. The purpose of this study was to compare the efficiency and safety of these techniques in pediatric patients.

MATERIALS AND METHODS

An extensive literature review regarding the clinical outcome, safety and efficiency of ETV and shunting in treatment of hydrocephalus was conducted in Medline, PubMed, Cochrane and Google Scholar databases up to 27 November 2015. Patient demographics, ETV and shunting success and failure rates were extracted.

RESULTS

A total of seven two-arm studies were included for quantitative analysis and 25 single-arm studies were included for systematic review. The two-arm studies recruited a total of 6995 patients: 1046 in the ETV group and 5949 in the shunt group. The pooled results showed that the 1 year success rate of ETV and shunt-placement procedure were similar (pooled RR = 0.870, 95% CI = 0.680-1.112, P = 0.266). The failure rate in the ETV treatment group was 0.9 times higher than in the shunt group; however, the results did not reach statistical significance (pooled RR = 0.893, 95% CI = 0.576-1.383, P = 0.611).

CONCLUSIONS

Both ETV and shunts are associated with similar 1 year success and failure rates. Therefore, there are no current indications to recommend one mode of treatment over the other. Future studies designed to assess the effectiveness of ETV and shunt procedures depending on patient's age and etiology are warranted.

Combined Predictive Model for Endoscopic Third Ventriculostomy Success in Adults and Children

BACKGROUND

The selection of patients in whom endoscopic third ventriculostomy (ETV) can be effective remains poorly defined. The ETV success score (ETVSS) and the presence of bowing of the third ventricle have been identified as independent factors for predicting success, each with limitations. The objective of this study is to elaborate a combined predictive model to predict ETV success in a mixed cohort of patients.

METHODS

Demographic, intraoperative, postoperative, and radiologic variables were analyzed in all ventriculostomies performed consecutively at a single institution from December 2004 to December 2022. Qualitative and quantitative measurements of preoperative, immediate, and late postoperative magnetic resonance imaging were conducted. Univariate analysis and logistic regression models were performed.

RESULTS

118 ETVs were performed in the selected period. Of these procedures, 106 met the inclusion criteria. The overall success rate was 71.7%, with a median follow-up of 3.64 years (interquartile range, 1.06-5.62). The median age was 36.1 years (interquartile range, 11.7-53.5). 35.84% were children (median, 7.81 years). Among the 80 patients with third ventricle bowing, the success rate was 88.8% (P < 0.001). Larger third ventricle dimensions on preoperative mid-sagittal magnetic resonance imaging were associated with increased ETV success. The model with the best receiver operating characteristic curves, with an area under the curve of 0.918 (95% confidence interval, 0.856-0.979) includes sex, ETVSS, presence of complications, and third ventricle bowing.

CONCLUSIONS

The presence of bowing of the third ventricle is strongly associated with a higher ETV success rate. However, a combined predictive model that integrates it with the ETVSS is the most appropriate approach for selecting patients for ETV.

Aspirator-Assisted Endoscopic Third Ventriculostomy in an Infant: 2-Dimensional Operative Video

Endoscopic third ventriculostomy (ETV) is an effective treatment for hydrocephalus in carefully selected patients.1 Studies have shown that larger ostomy size may be associated with higher ETV success and reduced ostomy closure in pediatric and adult patients.2-5 Therefore dilation of the ostomy is a key step in this procedure, which is traditionally accomplished with a balloon catheter, leaving behind loose redundant tissue at the ostomy site. In this 2-dimensional endoscopic operation (Video 1), we demonstrate the technique of using an aspiration device to enlarge the ETV ostomy in a controlled and efficient manner while eliminating redundant tissue. The patient is a 6-month-old girl with newly developed triventricular hydrocephalus seen on head ultrasound, manifested as upward gaze palsy, fontanelle fullness, and rapidly increasing head circumference. We chose to treat her with an ETV, given an ETV success score of 70.6,7 She underwent an ETV augmented with the NICO Myriad aspirator (NICO Corporation, Indianapolis, Indiana, USA) and achieved excellent clinical outcome. No intraoperative or postoperative complication occurred. Postoperative magnetic resonance imaging demonstrated an 8.4-mm ostomy on the third ventricular floor, nearly twice the size of a typical ETV ostomy.5 The key considerations in using this device include setting a low aspiration limit to avoid oversuction and using only mediolateral motion to avoid damage to the basilar artery. Future comparative studies are needed to investigate the efficacy, safety, and long-term outcome in aspirator-assisted ETV versus traditional techniques, as well as to evaluate ostomy size as an independent variable for long-term ETV success.

Anatomic variations of the floor of the third ventricle: Surgical implications for endoscopic third ventriculostomy

Background:

Endoscopic third ventriculostomy (ETV) is currently used as a treatment for different types of hydrocephalus. However, the anatomical endoscopic variants of the third ventricle floor (3VF), as well as their surgical implications, have been underrated. The anatomic variations of the 3VF can influence the technique and the success rate of the ETV. The purpose of this article is to describe the anatomical variations of 3VF, assess their incidence, and discuss the implications for ETV.

Methods:

Intraoperative videos of 216 patients who underwent ETV between January 2012 and February 2020 at Hospital Infantil Universitario de San José, Bogotá, Colombia were reviewed. One hundred and eighty patients who met the criteria to demonstrate the type of 3VF were selected.

Results:

3VF types were classified as follows: (1) Thinned, (2) thickened, (3) partially erased, (4) globular or herniated, and (5) narrowed.

Conclusion:

Knowledge of anatomical variations of the 3VF is paramount for ETV and it influences the success rate of the procedure.

Failure of Endoscopic Third Ventriculostomy

Endoscopic third ventriculostomy (ETV) is an alternative to cerebrospinal fluid (CSF) shunting in the treatment of hydrocephalus. Careful patient selection is critical as patient age, etiology of hydrocephalus, and previous shunting have been shown to influence ETV success rates. Intraoperatively, patient anatomy and medical stability may prevent or limit the completion of the ventriculostomy procedure, and findings such as a patulous third ventricular floor or cisternal scarring may portend a lower chance of successful hydrocephalus treatment. Patients in whom a ventriculostomy is completed may still experience continued symptoms of hydrocephalus or CSF leak, representing an early ETV failure. In other patients, the ETV may prove a durable treatment of hydrocephalus for several months or even years before recurrence of hydrocephalus symptoms. The failure pattern for ETV is different than that of shunting, with a higher early failure rate but improved long-term failure-free survival rates. The risk factors for failure, along with the presentation and management of failure, deserve review.

Endoscopic Third Ventriculostomy in Noncommunicating Hydrocephalus: Report on a Short Series of 53 Children

Introduction:

Endoscopoic third ventriculostomy (ETV) is currently considered the best alternative to cerebrospinal fluid (CSF) shunt systems in the treatment of obstructive hydrocephalus. The aim of ETV is to communicate the third ventricle with the interpendicular cistern and create CSF flow which bypasses an obstruction to the circulation of the CSF.

Aims and Objectives:

The purpose of this study was to elucidate the indications, efficacy, safety and outcome Of ETV pediatric patients of noncommunicating hydrocephalus.

Material and Methods:

This study is a 3 year prospective study from June 2012 to May 2015. Records were kept for age, gender, etilogical factors, symptoms, signs, previous use of shunt or external ventricular device, imaging findings, and surgical complications (intraoperative and postoperative). Only those patients with age between 6months and 18 years with symptoms of intracranial hypertension and radiographic evidence of noncommunicating hydrocephalus were included in the study.

Results:

A total of 53 patients were studied, out of these 29 were boys and 24 were girls. The mean age of the patients was 6.6 years. Overall a total of 50 successful ETVs were done in 53 patients. The success rate is estimated to be 94%. There was no mortality. The average postoperative hospital stay was 4 days. The followup ranged from 6 to 16 months (mean, 12 months).

Conclusion:

ETV in children is a safe, simple and effective treatment and a logical alternative to shunting procedure for patients of noncommunicating hydrocephalus.

Endoscopic third ventriculostomy in children with a fiber optic neuroendoscopy

OBJECTIVE

Endoscopic third ventriculostomy (ETV) provides a shunt-free treatment for obstructive hydrocephalus children. With rapidly evolving technology, the semi-rigid fiber optic neuroendoscopy shows a potential application in ETV by blunt fenestration. A retrospective analysis of our experience is reviewed.

METHODS

The authors review infants and children who underwent ETV using this technique from June 2004 to June 2016 with radiological and clinical follow-up done by a single surgeon. Patients who underwent ETV with channel scope were excluded. Demographic variables and operative reports were collected. Improvement of preoperative symptoms and avoidance of additional cerebrospinal fluid (CSF) diversion procedures were considered a success. The ETV success score (ETVSS) was used to correlate with clinical outcomes.

RESULTS

A total of 79 patients were included with a mean age of 8.3 ± 5.5 years, and 40.5% were female. The mean clinical and radiographic follow-up was 38.6 ± 40.9 months. The overall complication rate was 6.3%, while 73.4% were considered successful. The ETV failure cases received conversion to ventriculoperitoneal shunt or redo of ETV with a median time of 2 months. The mean ETV success score was 74.3 ± 11.8 with positive correlation between success rate (P < 0.05). Kaplan-Meier failure-free survival rates of 30-day, 90-day, 6-month, 1-year, and 2-year were 89.9, 83.5, 78.5, 75.9, and 74.6%. Eight patients required redo ETV, and five of these patients required eventual shunt placements. Approximately 61.9% of failure occurred within 3 months. Patients with post-intraventricular hemorrhage (IVH) /infection, and age younger than 12 months had the poorest outcome (P < 0.05).

CONCLUSIONS

Blunt dissection of the third ventricle floor under endoscopic vision with the stylet tip of a fiber optic neuroendoscopy is safe and requires less equipment in the pediatric population. This technique is successful with an optimistic long-term outcome except for infants and the post-IVH and infectious subgroups.

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.

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

Endoscopic third ventriculostomy (ETV) has become a popular technique for the treatment of hydrocephalus, but small sample size has limited the generalizability of prior studies. We performed a large-scale review of all available studies to help eliminate bias and determine how outcomes have changed and been influenced by patient selection over time. A systematic literature search was performed for studies of ETV that contained original, extractable patient data, and a meta-analytic model was generated for correlative and predictive analysis. A total of 130 studies were identified, which included 11,952 cases. Brain tumor or cyst was the most common hydrocephalus etiology, but high-risk etiologies, post-infectious or post-hemorrhagic hydrocephalus, accounted for 18.4%. Post-operative mortality was very low (0.2%) and morbidity was only slightly higher in developing than in industrialized countries. The rate of ETV failure was 34.7% and was higher in the first months and plateaued around 20months. As anticipated, ETV is less successful in high-risk etiologies of hydrocephalus and younger patients. Younger patient age and high-risk etiologies predicted failure. ETVs were performed more often in high-risk etiologies over time, but, surprisingly, there was no overall change in ETV success rate over time. This study should help to influence optimal patient selection and offer guidance in predicting outcomes.

Endoscopic third ventriculostomy in children: prospective, multicenter results from the Hydrocephalus Clinical Research Network

OBJECTIVE Endoscopic third ventriculostomy (ETV) is now established as a viable treatment option for a subgroup of children with hydrocephalus. Here, the authors report prospective, multicenter results from the Hydrocephalus Clinical Research Network (HCRN) to provide the most accurate determination of morbidity, complication incidence, and efficacy of ETV in children and to determine if intraoperative predictors of ETV success add substantially to preoperative predictors. METHODS All children undergoing a first ETV (without choroid plexus cauterization) at 1 of 7 HCRN centers up to June 2013 were included in the study and followed up for a minimum of 18 months. Data, including detailed intraoperative data, were prospectively collected as part of the HCRN's Core Data Project and included details of patient characteristics, ETV failure (need for repeat hydrocephalus surgery), and, in a subset of patients, postoperative complications up to the time of discharge. RESULTS Three hundred thirty-six eligible children underwent initial ETV, 18.8% of whom had undergone shunt placement prior to the ETV. The median age at ETV was 6.9 years (IQR 1.7-12.6), with 15.2% of the study cohort younger than 12 months of age. The most common etiologies were aqueductal stenosis (24.8%) and midbrain or tectal lesions (21.2%). Visible forniceal injury (16.6%) was more common than previously reported, whereas severe bleeding (1.8%), thalamic contusion (1.8%), venous injury (1.5%), hypothalamic contusion (1.5%), and major arterial injury (0.3%) were rare. The most common postoperative complications were CSF leak (4.4%), hyponatremia (3.9%), and pseudomeningocele (3.9%). New neurological deficit occurred in 1.5% cases, with 0.5% being permanent. One hundred forty-one patients had documented failure of their ETV requiring repeat hydrocephalus surgery during follow-up, 117 of them during the first 6 months postprocedure. Kaplan-Meier rates of 30-day, 90-day, 6-month, 1-year, and 2-year failure-free survival were 73.7%, 66.7%, 64.8%, 61.7%, and 57.8%, respectively. According to multivariate modeling, the preoperative ETV Success Score (ETVSS) was associated with ETV success (p < 0.001), as was the intraoperative ability to visualize a "naked" basilar artery (p = 0.023). CONCLUSIONS The authors' documented experience represents the most detailed account of ETV results in North America and provides the most accurate picture to date of ETV success and complications, based on contemporaneously collected prospective data. Serious complications with ETV are low. In addition to the ETVSS, visualization of a naked basilar artery is predictive of ETV success.

Endoscopic neurosurgery in preterm and term newborn infants--a feasibility report

OBJECTIVE

Neuroendoscopic procedures became essential in neurosurgical treatment of disturbed cerebrospinal fluid dynamics. While a vast number of papers report on the neuroendoscopic experience for adults and children, no series so far reported on techniques and indications for neonate infants. We present our experience for the feasibility of neuroendoscopic procedures in preterm and term newborn infants.

METHODS

All preterm and term infants who underwent an endoscopic neurosurgical intervention prior to the 28th day after the previously estimated date of delivery were identified by retrospective review. Surgical procedures and techniques, complications, and further follow-up data are reported.

RESULTS

During the study period, 14 infants (median age at surgery, 36+(2)/7 weeks of gestation) underwent 20 endoscopic procedures. The performed procedures included endoscopic septostomy (n = 3), endoscopic shunt placement for multiloculated hydrocephalus (n = 4), endoscopic transaqueductal stenting for isolated fourth ventricle (n = 3), and endoscopic lavage for ventriculitis (n = 4) or for intraventricular hemorrhage (n = 6). No severe complications were seen, while two patients necessitating unexpected interventions during further follow-up (10 %).

CONCLUSIONS

Despite the fragility of preterm and term newborn infants, neuroendoscopic procedures may play an important role in the treatment of disturbed cerebrospinal fluid (CSF) dynamics also in this patient population. The neuroendoscopic approach may be curative in conditions like isolated lateral ventricle, may facilitate simplified and effective CSF diversion in multiloculated hydrocephalus or isolated fourth ventricle, and may be beneficial in the course of ventriculitis and intraventricular hemorrhage. Further studies must verify our experience with a bigger cohort of patients and on a multicenter basis.

Use of the NeuroBalloon catheter for endoscopic third ventriculostomy

Endoscopic third ventriculostomy (ETV) has become the procedure of choice for treatment of obstructive hydrocephalus. While patient selection is the most critical factor in determining the success of an ETV procedure, the technical challenge lies in the proper site of fenestration and the successful creation of a patent stoma. Positioning of a single balloon catheter at the level or below the floor of the third ventricle to achieve an optimal ventriculostomy can at times be challenging. Here, the authors describe the use of a double-barrel balloon catheter (NeuroBalloon catheter), which facilitates positioning across, as well as dilation of, the floor of the third ventricle. The surgical technique and nuances of using the NeuroBalloon catheter and the experience in more than 1000 cases are described. The occurrence of vascular injury was less than 0.1%, and the risk of balloon rupture was less than 2%. The authors found that the placement and deployment of this balloon catheter facilitate the creation of an adequate ventriculostomy in a few simple steps.

Preoperative third ventricular bowing as a predictor of endoscopic third ventriculostomy success

OBJECT

Patients with hydrocephalus often present with both intraventricular obstructive and communicating components, and determination of the predominant component is difficult. Other investigators have observed that third ventricular floor deformation, or "bowing" of the third ventricular floor, is a good indicator of intraventricular obstructive hydrocephalus, resulting in higher success rates with endoscopic third ventriculostomy (ETV). However, additional third ventricular bowing assessment and statistical evidence demonstrating a difference in ETV outcome with third ventricular bowing is needed. The authors hypothesized that patients with preoperative bowing of the third ventricle would exhibit greater long-term success rates after ETV and that lack of bowing would result in increased failure rates after ETV.

METHODS

The authors determined success and failure for 59 ETVs performed in 56 patients, and recorded patient age, time to failure, and preoperative third ventricular anatomy, as well as history of infection, intraventricular hemorrhage, and previous shunt. Third ventricular anatomy was assessed on MR imaging for bowing, which was classified as any of the following: depression of the third ventricular floor, enlargement of the supraoptic recess, anterior curvature of the lamina terminalis, dilation of the proximal aqueduct to a greater extent than the distal aqueduct, and blunting or posterior bowing of the suprapineal recess. Univariate and multivariate analyses of ETV failure and the time to failure were performed using logistic regression and the Cox proportional hazards model, respectively.

RESULTS

After adjusting for patient age and history of infection, there was a significant association between lack of anterior third ventricular preoperative bowing (either lamina terminalis, supraoptic recess, or third ventricular floor) and ETV failure (adjusted HR 2.79, 95% CI 1.08-7.20). Of the patients with bowing, 70.5% experienced success with ETV, as did 33.3% of the patients without bowing. Among the individual structures, absence of bowing in the anterior aspect of the third ventricular floor was significantly associated with censored time to ETV failure (multivariate HR 2.59, 95% CI 1.01-6.66; final model including age and history of infection).

CONCLUSIONS

The presence of preoperative third ventricular bowing is predictive of ETV success, with nearly a 3-fold likelihood of success compared with patients treated with ETV in the absence of such bowing. Although bowing is predictive, 33% of patients without bowing were also treated successfully with ETV.

The constant flow ventricular infusion test: a simple and useful study in the diagnosis of third ventriculostomy failure

Object

The evaluation of third ventriculostomy function in hydrocephalic patients is challenging. The utility of the constant flow infusion test in predicting response to shunt insertion in normal-pressure hydrocephalus, as well as in identifying shunt malfunction, has been previously demonstrated. The object of this study was to evaluate its usefulness in determining whether a revision CSF diversion procedure was indicated in patients presenting with recurring symptoms and persisting ventriculomegaly after endoscopic third ventriculostomy (ETV).

Methods

The authors conducted a prospective study of all patients who, after undergoing ETV at their institution, presented postoperatively with recurring symptoms and persisting ventriculomegaly.

Results

Forty-six patients (mean age 40.7 years, including 11 patients younger than 18 years) underwent 56 constant flow ventricular infusion tests (VITs) at a mean of 24.7 months post-ETV. Thirty-three patients with resistance to CSF outflow (Rout) less than 13 mm Hg/ml/min underwent follow-up (median 17 months) and experienced resolution of symptoms. In 10 episodes Rout was greater than 13 mm Hg/ml/min; the patients in these cases underwent revisional CSF diversion. Two patients demonstrated high and frequent B (slow) waves despite a low Rout; these patients also underwent successful revisions. Patients who improved after surgery had increased B wave activity in the plateau phase of the VIT (p = 0.01). Thirty-four patients underwent MR imaging at the same time; 4 had high Rout despite evidence of flow across the stoma. These 4 patients underwent surgery and experienced resolution of symptoms. Of 9 patients without flow, Rout was less than 13 mm Hg/ml/min in 4; these patients were successfully treated conservatively.

Conclusions

The VIT is a useful and safe adjunct to clinical and MR imaging evaluation when ETV failure is suspected.

Endoscopic third ventriculostomy in the treatment of childhood hydrocephalus: validation of a success score that predicts long-term outcome

OBJECT

The goal of this study was to externally validate the proposed Endoscopic Third Ventriculostomy Success Score (ETVSS), which predicts successful treatment for hydrocephalus on the basis of a child's individual characteristics.

METHODS

The authors retrospectively identified 181 cases of consecutive endoscopic third ventriculostomy (ETV) performed in children at a single neurosurgery center in the United Kingdom. They compared actual success at both 6 and 36 months, with mean predicted probabilities for low, moderate, and high chance of success strata based on the ETVSS. Long-term success was calculated using Kaplan-Meier methods and comparisons were made by means of unpaired t-tests.

RESULTS

Overall, 166 primary ETVs were performed; ETV success was 72.9% at 6 and 64.5% at 36 months. At long-term follow-up, the mean predicted probability of success was significantly higher in those with a successful ETV (99 patients) than in those with a failed ETV (67 patients) (p = 0.001). The ETVSS accurately predicted outcome at 36 months; the low, medium, and high chance of success strata had mean predicted probabilities of success of 82%, 63%, and 36%, and actual success of 76%, 66%, and 42%, respectively. The overall complication rate was 6%.

CONCLUSIONS

The ETVSS closely predicted the overall long-term success rates in high-, moderate-, and low-risk groups. The results of this study suggest that the ETVSS will aid clinical decision making in predicting outcome of ETV.

Evaluating the Children's Hospital of Alabama endoscopic third ventriculostomy experience using the Endoscopic Third Ventriculostomy Success Score: an external validation study

OBJECT

Endoscopic third ventriculostomy (ETV) success is dependent on patient characteristics including age, origin of hydrocephalus, and history of shunt therapy. Using these factors, an Endoscopic Third Ventriculostomy Success Score (ETVSS) model was constructed to predict success of therapy. This study reports a single-institution experience with ETV and explores the ETVSS model validity.

METHODS

A retrospective chart review identified 151 consecutive patients who underwent ETV at a pediatric hospital between August 1995 and December 2009. Of these 151, 136 patients had at least 6 months of clinical follow-up. Data concerning patient characteristics, operative characteristics, radiological findings, complications, and success of ETV were collected. The actual success rates were compared with those predicted by the ETVSS model.

RESULTS

The actual success rate of ETV at 6 months was 68.4% (93 of 136 patients), which compared well to the predicted ETVSS of 76.5% ± 12.5% (± SD). The C-statistic was 0.74 (95% CI 0.65-0.83), suggesting that the ability of the ETVSS to discriminate failures from successes was good. Secondary ETV was found to have a hazard ratio for failure of 4.2 (95% CI 2.4-7.2) compared with primary ETV (p < 0.001). The complication rate was 9.3% with no deaths. At the first radiological follow-up, the increased size of ventricles had a hazard ratio for failure of 3.0 (95% CI 1.5-6.0) compared with patients in whom ventricle size either remained stable or decreased (p = 0.002).

CONCLUSIONS

The ETVSS closely predicts the actual success of ETV, fitting the statistical model well. Shortcomings of the model were identified in overestimating success in patients with ETVSS ≤ 70, which may be attributable to the poor success of secondary ETVs in the authors' patient population.

Endoscopic third ventriculostomy in patients with shunt malfunction

OBJECTIVE

This paper presents data from a retrospective study of endoscopic third ventriculostomy (ETV) in patients with shunt malfunction and proposes a simple and reasonable post-operative protocol that can detect ETV failure.

METHODS

We enrolled 19 consecutive hydrocephalus patients (11 male and 8 female) who were treated with ETV between April 2001 and July 2010 after failure of previously placed shunts. We evaluated for correlations between the success rate of ETV and the following parameters : age at the time of surgery, etiology of hydrocephalus, number of shunt revisions, interval between the initial diagnosis of hydrocephalus or the last shunt placement and ETV, and the indwelling time of external ventricular drainage.

RESULTS

At the time of ETV after shunt failure, 14 of the 19 patients were in the pediatric age group and 5 were adults, with ages ranging from 14 months to 42 years (median age, 12 years). The patients had initially been diagnosed with hydrocephalus between the ages of 1 month 24 days and 32 years (median age, 6 years 3 months). The etiology of hydrocephalus was neoplasm in 7 patients; infection in 5; malformation, such as aqueductal stenosis or megacisterna magna in 3; trauma in 1; and unknown in 3. The overall success rate during the median follow-up duration of 1.4 years (9 days to 8.7 years) after secondary ETV was 68.4%. None of the possible contributing factors for successful ETV, including age (p=0.97) and the etiology of hydrocephalus (p=0.79), were statistically correlated with outcomes in our series.

CONCLUSION

The use of ETV in patients with shunt malfunction resulted in shunt independence in 68.4% of cases. Age, etiology of hydrocephalus, and other contributing factors were not statistically correlated with ETV success. External ventricular drainage management during the immediate post-ETV period is a good means of detecting ETV failure.

A retrospective analysis of revision endoscopic third ventriculostomy

PURPOSE

Endoscopic third ventriculostomy (ETV) has gained favour as an effective treatment for obstructive hydrocephalus. However, the timing of ETV failure and the long-term efficacy of revision ETV remain poorly documented.

METHODS

A retrospective review was performed of patients undergoing revision ETV between 1999 and 2007. Only those patients in whom there was evidence of a good sustained clinical improvement after the initial ETV were considered candidates for ETV revision. All other patients underwent insertion of a ventriculoperitoneal shunt at the time of ETV failure. Failures that were selected for repeat ETV were subdivided into; "early" if the revision occurred within the first 3 months of the primary procedure and "late" if occurring after this.

RESULTS

Ten patients underwent revision ETV (6% of all ETVs performed). Age ranged from 2 months to 32 years (mean 13.6 years). Three "early" revision ETV were performed at a mean of 1.3 months, and there were seven "late" revisions performed at a mean of 27 months. The stoma was closed in seven patients and narrowed in one patient, and a second membrane was found under the original patent stoma in a further two patients. In two patients, a third ETV procedure was performed (both at 1 month after second ETV), and the stoma was closed in both these patients. No patients have required a shunt.

CONCLUSION

At last follow-up (mean 38 months), all patients remain well. Revision ETV appears a safe and effective means of managing hydrocephalus-providing there is clinical evidence that the primary procedure was initially effective. It is important to emphasise that patients with an initially successful ETV are by no means "cured".

Surgery for hydrocephalus in sub-Saharan Africa versus developed nations: a risk-adjusted comparison of outcome

PURPOSE

Surgery for children in developing nations is challenging. Endoscopic third ventriculostomy (ETV) is an important surgical treatment for childhood hydrocephalus and has been performed in developing nations, but with lower success rates than in developed nations. It is not known if the lower success rate is due to inherent differences in prognostic factors.

METHODS

We analyzed a large cohort of children (≤20 years old) treated with ETV in developed nations (618 patients from Canada, Israel, United Kingdom) and developing nations of sub-Saharan Africa (979 patients treated in Uganda). Risk-adjusted survival analysis was performed.

RESULTS

The risk of an intra-operative ETV failure (an aborted procedure) was significantly higher in Uganda regardless of risk adjustment (hazard ratio (HR), 95% confidence interval (CI), 11.00 (6.01 to 19.84) P<0.001). After adjustment for patient prognostic factors and technical variation in the procedure (the use of choroid plexus cauterization), there was no difference in the risk of failure for completed ETVs (HR, 95% CI, 1.04 (0.83 to 1.29), P=0.74).

CONCLUSIONS

Three factors account for all significant differences in ETV failure between Uganda and developed nations: patient prognostic factors, technical variation in the procedure, and intra-operatively aborted cases. Once adjusted for these, the response to completed ETVs of children in Uganda is no different than that of children in developed nations.

Endoscopic third ventriculostomy in patients younger than 2 years: outcome analysis of 41 hydrocephalus cases

OBJECT

The object of this study was to analyze the outcome of endoscopic third ventriculostomy (ETV) in patients under 2 years of age and investigate factors related to ETV success or failure in this patient population.

METHODS

The authors reviewed their experience in using endoscopic third ventriculostomy (ETV) in the treatment of 41 hydrocephalus patients younger than 2 years. The mean duration of follow-up was 45 months. The relationship between ETV efficacy and the following variables was analyzed: cause of hydrocephalus, level of CSF occlusion, primary versus secondary ETV, type of surgical procedure, head circumference, patient age at ETV, patient age at first manifestation of hydrocephalus, and anatomical features of the ventricle. Success of ETV was assessed based on the results of neurological examination and postoperative imaging during the follow-up period.

RESULTS

The authors performed 32 primary ETVs and 10 secondary ETVs (ETV after hydrocephalus surgery) in 41 patients (a second ETV was performed in 1 patient). The success rates of primary and secondary ETV were 75.8 and 55.6%, respectively (no significant difference, p = 0.15). The ETV was clinically and radiologically successful in 30 (71.4%) of 42 procedures during a mean (+/- SD) follow-up period of 45.0 +/- 4.8 months (range 12-127 months). A negative relationship was found between success of ETV and the thickness of the floor of the third ventricle (the most effective procedures were those in which the floor of the ventricle was thinnest [p < 0.05]). There was a highly significant correlation between ETV success and prolapse of the ventricle floor (p < 0.001). Also, there was an inverse relationship between ventricle floor thickness and the width of the third ventricle (p < 0.005). In our group of patients there was significant correlation between ETV success and patient age at onset of hydrocephalus (the most effective procedures were in patients in whom signs of hydrocephalus first occurred after 1 month of age [p = 0.02]).

CONCLUSIONS

Endoscopic third ventriculostomy was successful in 71.4% of procedures in children younger than 2 years and in 75.0% of procedures in infants. Success of ETV in children younger than 2 years depends not on the age of the patient or cause of hydrocephalus but on the thickness of the floor of the third ventricle and the patient's age at first manifestation of hydrocephalus.

Endoscopic third ventriculostomy in the treatment of childhood hydrocephalus

OBJECTIVE

To develop a model to predict the probability of endoscopic third ventriculostomy (ETV) success in the treatment for hydrocephalus on the basis of a child's individual characteristics.

STUDY DESIGN

We analyzed 618 ETVs performed consecutively on children at 12 international institutions to identify predictors of ETV success at 6 months. A multivariable logistic regression model was developed on 70% of the dataset (training set) and validated on 30% of the dataset (validation set).

RESULTS

In the training set, 305/455 ETVs (67.0%) were successful. The regression model (containing patient age, cause of hydrocephalus, and previous cerebrospinal fluid shunt) demonstrated good fit (Hosmer-Lemeshow, P = .78) and discrimination (C statistic = 0.70). In the validation set, 105/163 ETVs (64.4%) were successful and the model maintained good fit (Hosmer-Lemeshow, P = .45), discrimination (C statistic = 0.68), and calibration (calibration slope = 0.88). A simplified ETV Success Score was devised that closely approximates the predicted probability of ETV success.

CONCLUSIONS

Children most likely to succeed with ETV can now be accurately identified and spared the long-term complications of CSF shunting.

Intraoperative assessment of endoscopic third ventriculostomy success

OBJECT

The authors' aim in this study was to determine if standardizing the evaluation of intraoperative findings during endoscopic third ventriculostomy (ETV) could predict patients with hydrocephalus in whom endoscopic treatment will fail and require ventriculoperitoneal shunt treatment. The creation of a uniform scale with predictive outcomes may reduce returns to the operating room for shunt treatment and reliance on postoperative externalized ventricular monitoring and MR imaging.

METHODS

The authors evaluated the preoperative history, intraoperative findings, and postoperative monitoring and imaging findings in 109 consecutive patients undergoing 112 consecutive attempted ETVs for obstructive hydrocephalus. A 5-grade scale was developed to assess preoperative risk factors and intraoperative evaluation to unify criteria that have been suspected to influence outcome independently. A grade of 0 was assigned to patients with no negative predictors, whereas increasing scores were assigned to patients who had multiple preoperative and intraoperative risks identified. Patients' grades were compared with outcome of the procedure, utility of externalized ventricular monitoring, and results of postoperative MR imaging.

RESULTS

Of 112 ETVs, 77 were successful and 35 were unsuccessful. Fifty-nine patients received a grade of 0, 27 received a grade of 1, 11 received a grade of 2, and 15 received a grade of > or = 3. In all 15 patients receiving a grade > or = 3 attempted ETV procedures failed, and the patients required a ventriculoperitoneal shunt. Postoperative monitoring with externalized ventricular drains and MR images demonstrating radiographic evidence of flow was independently less reliable than intraoperative grading in predicting success. Patients with a grade of 0 almost uniformly had successful surgery, independent of MR imaging findings. Patients with a grade of 1 or 2 who had successful surgery almost always lacked negative intraoperative predictive findings.

CONCLUSIONS

Despite reliance in recent years on post-ETV MR images and externalized ventricular monitoring, these modalities, although often useful adjuncts, appear less reliable as predictive tests than a simple assessment at the time of endoscopic fenestration. By using a uniform grading scale, the authors have introduced a novel means through which intraoperative and postoperative decision making can be aided, with the goal of reducing unnecessary procedures and tests and preventing unnecessary returns to the operating room.

Endoscopic third ventriculostomy for obstructive hydrocephalus in children younger than 6 months of age: is it a first-choice method?

INTRODUCTION

Endoscopic third ventriculostomy (ETV) is considered a safe procedure and is a method of choice in treatment of obstructive hydrocephalus nowadays. In case of Sylvian aqueduct stenosis, the success rate reaches 90%. In children younger than 6 to 24 months, respectively, however, some authors report lower effectiveness ranging between 0% and 64%. The reasons of ETV failure are discussed: hyporesorption in patients with obstruction as a consequence of hemorrhage or infection, suboptimal ETV performance, especially in premature newborns, or the theory of different cerebrospinal fluid circulation in newborn babies.

MATERIALS AND METHODS

Between January 2005 and December 2006 in our clinic, 14 patients younger than 6 months having presented with obstructive hydrocephalus were treated endoscopically. Obstruction was revealed by preoperative magnetic resonance imaging. The etiology of hydrocephalus was congenital aqueduct stenosis in five patients, posthemorrhagic obstruction in eight patients, and combination of posthemorrhagic and postinfection etiology in one patient. ETV was considered successful when no shunt operation was needed in the patient.

RESULTS

ETV was successful in eight patients who experienced regression of signs of intracranial hypertension and were not forced to undergo ventriculo-peritoneal (V-P) shunting. In one patient, a successful repeat ETV was performed. In the remaining six patients, V-P shunt implantation was necessary. Total success rate in our group of patients was 57%. The only complication was subdural hygroma in one patient requiring evacuation.

CONCLUSION

Based on our experience, we recommend ETV as the method of choice in children younger than 6 month of age.

Complications of endoscopic third ventriculostomy

OBJECTS

Although endoscopic third ventriculostomy (ETV) is considered as the first choice in the management of noncommunicating hydrocephalus, it is not without risk or complication.

METHODS

The patients who had undergone ETV only between 1998 and 2005 were retrospectively reviewed. There were 85 males and 70 females, and 173 ETVs were performed in 155 patients. The patients' age ranged from 2 months to 77 years. Complications were categorized as (1) intraoperative, (2) early postoperative (<1 month), and (3) late postoperative (>1 month). Follow-up of the patients ranged from 1 to 86 months.

RESULTS

Overall complication rate per patient was 15.4%, and complication per procedure was 18%. Complication rate significantly varied with the etiology of hydrocephalus (P = 0.013). The patients with Chiari type I malformation and tumor had no or very low complication rates. The complication risk was significantly higher in repeat endoscopic procedure (55.5%) than in the first procedure (10%; P = 0.0001).

CONCLUSION

ETV should be the first choice in the management of noncommunicating hydrocephalus. Training, experience, and meticulous technique will decrease the complication rate. Patients undergoing ETV should be followed in a similar manner to patients with cerebrospinal fluid shunts.

Role of galeal-pericranial flap in reducing postoperative CSF leak in patients with intracranial endoscopic procedures

OBJECTIVE

The authors describe a simple technique to reduce the incidence of cerebrospinal fluid (CSF) leak following endoscopic third ventriculostomy and other neuroendoscopic procedures.

METHODS

After the scalp incision, the galea and pericranium are reflected in a single layer after the scalp incision which is then closed in a watertight fashion after the procedure is completed. The securely closed flap prevents minor CSF leaks which would have otherwise required intermittent CSF drainage procedures.

CONCLUSION

This simple procedural modification is effective in children with thin cortical mantle and large ventricles who are otherwise highly susceptible for CSF leak in the postoperative period.

LASER-ASSISTED ENDOSCOPIC THIRD VENTRICULOSTOMY

OBJECTIVE

Endoscopic third ventriculostomy is a well-known surgical option in the treatment of noncommunicating hydrocephalus. We studied complications and long-term success in 202 patients to demonstrate the safety and efficacy of laser-assisted endoscopic third ventriculostomy (LA-ETV) using a unique “black” fiber tip/diode laser combination for controlled tissue ablation.

METHODS

We studied 213 LA-ETVs, which were performed in 202 patients. Patients' ages ranged from 2 days to 83 years (mean age, 27 yr). The mean follow-up period for all patients was 2.7 years (range, 2 d to 12 yr). Hydrocephalus was caused by aqueductal stenosis in 65 patients, tumors in 67 patients, hemorrhages in 24 patients, myelomeningoceles in 20 patients, cysts in 15 patients, and other causes in 11 patients. The long-term effectiveness of LA-ETV was studied with Kaplan-Meier analysis.

RESULTS

Technically successful LA-ETVs were accomplished in 196 of the 202 patients (97%). The overall success rate for a functional LA-ETV was 68% at the 2-year follow-up evaluation. LA-ETV was more effective in patients aged 1 year and older (70% success rate) than in younger patients (59% success rate). Success rates were greater in patients with aqueductal stenosis or tumors as compared to other etiologies. Complications occurred in 22 procedures (10.3%). Only one patient (0.5%) experienced a major complication. No surgical mortalities or laser-related complications occurred.

CONCLUSION

This study demonstrates that LA-ETV is a safe and effective procedure that is comparable to other techniques for ETV. LA-ETV is most effective in patients aged 1 year and older and in patients with aqueductal stenosis and tumors, with a low major complication rate.