Endoscopic Third Ventriculostomy in Patients with Malfunctioning CSF-Shunt

Clinical Outcome of Endoscopic Procedure in Patients with Shunt Malfunction

OBJECTIVE

The goal of this study was to analyze the clinical outcomes of endoscopic third ventriculostomy (ETV) and endoscopic septostomy when shunt malfunction occurs in a patient who has previously undergone placement of a ventriculoperitoneal shunt.

METHODS

From 2001 to 2020 at Seoul National University Children's Hospital, patients who underwent ETV or endoscopic septostomy for shunt malfunction were retrospectively analyzed. Initial diagnosis (etiology of hydrocephalus), age at first shunt insertion, age at endoscopic procedure, magnetic resonance or computed tomography image, subsequent shunting data, and follow-up period were included.

RESULTS

Thirty-six patients were included in this retrospective study. Twenty-nine patients, 18 males and 11 females, with shunt malfunction underwent ETV. At the time of shunting, the age ranged from 1 day to 15.4 years (mean, 2.4 years). The mean age at the time of ETV was 13.1 years (range, 0.7 to 29.6 years). Nineteen patients remained shunt revision free. The 5-year shunt revisionfree survival rate was 69% (95% confidence interval [CI], 0.54-0.88). Seven patients, three males and four females, with shunt malfunction underwent endoscopic septostomy. At the time of shunting, the age ranged from 0.2 to 12 years (mean, 3.9 years). The mean age at the time of endoscopic septostomy was 11.9 years (range, 0.5 to 29.5 years). Four patients remained free of shunt revision or addition. The 5-year shunt revision-free survival rate was 57% (95% CI, 0.3-1.0). There were no complications associated with the endoscopic procedures.

CONCLUSION

The results of our study demonstrate that ETV or endoscopic septostomy can be effective and safe in patients with shunt malfunction.

Converting Pediatric Patients and Young Adults From a Shunt to a Third Ventriculostomy: A Multicenter Evaluation

BACKGROUND

Endoscopic third ventriculostomy (ETV) is an effective primary treatment for certain forms of hydrocephalus. However, its use in children with an existing shunt is less well known.

OBJECTIVE

To report a multicenter experience in attempting to convert patients from shunt dependence to a third ventriculostomy and to determine predictors of success.

METHODS

Three participating centers provided retrospectively collected information on patients with an attempted conversion from a shunt to an ETV between December 1, 2008, and April 1, 2018. Demographic, clinical, and radiological data were recorded. Success was defined as shunt independence at the last follow-up.

RESULTS

Eighty patients with an existing ventricular shunt underwent an ETV. The median age at the time of the index ETV was 9.9 yr, and 44 (55%) patients were male. The overall success rate was 64% (51/80), with a median duration of follow-up of 2.0 yr (range, 0.1-9.4 yr). Four patients required a successful repeat ETV at a median of 1.7 yr (range, 0.1-5.7 yr) following the index ETV. Only age was predictive of ETV failure on multivariate analysis (odds ratio 0.86 [95% CI 0.78-0.94], P = .005). No patient less than 6 mo of age underwent an ETV, and of the 5 patients between 6 and 12 mo of age, 4 failed.

CONCLUSION

Although not every shunted patient will be a candidate for an ETV, nor will they be successfully converted, an ETV should at least be considered in every child who presents with a shunt malfunction or who has an externalized shunt.

Functional and Radiological Parameters to Assess Outcome of Endoscopic Third Ventriculostomy in Shunt Failure Patients

Background:

Placement of ventriculoperitoneal shunt is a standard treatment for hydrocephalus. The risk of shunt malfunction in the first year is 25%–40% making endoscopic third ventriculostomy (ETV) a feasible option in those patients with shunt failure.

Aim:

The aim of this study was to evaluate ETV as a viable option in patients with shunt malfunction and to correlate the clinical outcome following successful ETV with functional and radiological outcomes.

Materials and Methods:

All patients who underwent ETV as a diversion procedure for hydrocephalus following shunt failure or malfunction over 1 year were studied. Functional outcome was evaluated by Wee function independence measure score carried out preoperatively, postoperatively, and at 6-month follow-up. Similar comparison was carried out for radiological parameters such as effacement of gyri, periventricular lucency, frontal horn diameter (maximum), Evans’ index, and third ventricular diameter.

Results:

Of 15 patients, 61.5% were shunt free after ETV. All the failures were noted in the first month following the procedure. The factors, which showed statistically significant correlation with the outcome of ETV, included age (P = 0.030), preoperative functional score (P = 0.006), and all the three components of the functional scoring, namely self-care score (P = 0.087), motor control score (P = 0.035), and neurocognitive score (P = 0.003). Parameters such as Evans’ index, maximum frontal horn diameter, and third ventricular diameter showed no significant difference between preoperative and postoperative scans. In follow-up imaging, only the frontal horn diameter showed a significant improvement (P = 0.047).

Conclusion:

ETV leads to significant neurocognitive improvement and postoperative functional status making it a viable option in patients who present with shunt malfunction.

Role of Secondary Endoscopic Third Ventriculostomy in Children: Review of an Institutional Experience

BACKGROUND

Endoscopic third ventriculostomy (ETV) has become a standard and safe procedure for obstructive hydrocephalus. ETV can also play an important role in children presenting with shunt malfunction with an added advantage of shunt independence. Secondary ETV can be defined as either a redo endoscopic ventriculostomy done after primary ETV stoma closure or that done in cases presenting with shunt malfunction.

OBJECTIVE

The aim of our study was to evaluate the role of secondary ETV in the pediatric age group patients.

METHODS

This is a retrospective analysis of 36 children (<18 years) who underwent ETV after shunt malfunction and 4 children with ETV done after previous ETV stoma closure from 2004 until 2018. In all patients, the obstructive pattern suggesting aqueduct outflow obstruction was observed on MRI. Patients were followed up for a mean period of 4.25 years.

RESULTS

ETV was considered successful if the patient avoided a shunt insertion later on in their life. Considering this definition, a success rate of 72% was observed with secondary ETV for shunt malfunction whereas a success rate of 75% was observed after primary ETV failure without any major side effects in any of the patients.

CONCLUSION

ETV can be considered a primary treatment modality in children with shunt malfunction and has a good success rate in cases presenting with closure of previously performed ETV stoma.

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.

Controversy about Management of Hydrocephalus - Shunt vs. Endoscopic Third Ventriculostomy

The best management of hydrocephalus is still controversial in the twenty-first century. Shunt treatment for hydrocephalus is the most common procedure performed in neurosurgical practice and is associated with the highest complications rate. But during the last 2 decades, the treatment of hydrocephalus has improved with better shunt devices available today, increased facilities for investigations and newer approaches like endoscopic third ventriculostomy. The recent advances in development of better endoscopes have provided the patient and treating doctor with an option for an alternative surgery for treatment of hydrocephalus.

Endoscopic Third Ventriculostomy: Success and Failure

Endoscopic third ventriculostomy (ETV) has now become an accepted mode of hydrocephalus treatment in children. Varying degrees of success for the procedure have been reported depending on the type and etiology of hydrocephalus, age of the patient and certain technical parameters. Review of these factors for predictability of success, complications and validation of success score is presented.

Markedly Improved Success Rate of Endoscopically Assisted Third Ventriculostomy Is Achieved by Routine Placement of External Lumbar Drain

Hydrocephalus is a major cause of patient decreased quality of life and high health care financial burden in the United States and throughout the world. The placement of ventricular shunts (ventriculoperitoneal shunt) has proven to be a safe treatment for hydrocephalus, but it is associated with a high complication rate leading to a lower quality of life and continued financial burden for patients, their families, and society as a whole. The endoscopically assisted third ventriculostomy (ETV) has been practiced as an alternative to ventricular shunting since the 1990s. Success rates vary widely and there are many factors which contribute to the varying success rates. The ETV procedure has the potential to alleviate much of the overall quality of life issues and some of the financial burdens associated with hydrocephalus provided success rates can be increased and the procedure and management techniques are adopted more widely. Common techniques have been published in the past which report associated improvements in success rates amongst individual surgeons. Here, we report a novel perioperative technique and management strategy that displays a higher than reported success rate. Our methods and results show potential to significantly improve overall ETV success rates if reproduced and subsequently adopted widely. We retrospectively studied records of 24 adult patients with hydrocephalus who were treated with an ETV procedure. Routinely, we placed an external lumbar drain postoperatively which was continued for a minimum of 2 days. There was a 95.8% success rate at 30 days. The overall success rate was 83.3%. This is significantly higher than the average of the predicted success scores calculated by the ETV success scoring system (71.8%). It is also significantly higher than previous studies' reported ETV success rates in adults. We propose additional similar studies to be performed to test the reproducibility of increased success rates using our technique, ideally through a prospective, randomized, multicenter trial.

Simultaneous ventriculoperitoneal shunt removal and endoscopic third ventriculostomy for three patients previously treated for intracranial germ cell tumors more than 20 years ago

BACKGROUND

Obstructive hydrocephalus is the most common complication of intracranial germ cell tumors (IGCTs). Although ventriculoperitoneal shunts (VPSs) were previously used for treating this condition, they have recently been replaced by endoscopic third ventriculostomy (ETV), as the latter can avoid various complications caused by a VPS and can preserve physiological cerebrospinal fluid (CSF) dynamics. Therefore, if a VPS malfunctioned in patients who had previously been treated for IGCTs, it seems reasonable to consider removing the problematic VPS, followed by ETV, as long as magnetic resonance imaging reveals third ventricle floor ballooning and the cause of obstruction in the ventricular system, which are indicators for ETV.

CASE PRESENTATION AND DISCUSSION

Here, we present the cases of three patients who underwent simultaneous removal of malfunctioning VPSs and ETV, more than 20 years (range 20-27 years) after initial treatment for IGCT and relevant obstructive hydrocephalus. Despite a relatively long shunt dependency, their obstructive hydrocephalus was well-managed by ETV, probably because CSF absorptive capacity remained intact after IGCT ablation by radio-chemotherapy.

CONCLUSION

Patients with previously treated IGCTs can thus be released from the need for a VPS, regardless of long-term shunt dependency.

Endoscopic Third Ventriculostomy Instead of Shunt Revision in Children Younger Than 3 Years of Age

OBJECTIVE

Endoscopic third ventriculostomy (ETV) is a valuable option in the treatment of shunt failure, but no clinical data exist for young children. The aim of this study was to elucidate the role of ETV in patients younger than 3 years of age with shunt malfunction.

METHODS

A cohort of 37 patients younger than 3 years of age with shunt malfunction underwent ETV instead of shunt revision. Patients' preoperative condition and medical history were studied to determine the impact of a number of variables on outcome. The Fisher exact test was used to assess differences among groups.

RESULTS

Median age at ETV was 21.6 months (8-36 months). Diagnosis was obstructive hydrocephalus in 24 patients and communicating hydrocephalus in 13. Median age at initial shunt placement was 3.2 months (10 days to 30 months). The etiology of shunt malfunction was obstruction (n = 27) or infection (n = 10). Overall ETV failure rate was 40.5% (15/37). Patients whose age at initial shunt placement was <6 months and/or who had a preterm birth history had higher relative rates of ETV failure. Other variables, including type of hydrocephalus, interval between initial shunt placement and ETV, history of intraventricular bleeding and/or infection, and etiology of shunt malfunction, did not significantly affect the final outcome.

CONCLUSIONS

Patients younger than 3 years with obstructive or communicating hydrocephalus may benefit from ETV in the event of shunt malfunction and have about a 60% probability of becoming shunt free.

Predicting success of endoscopic third ventriculostomy: validation of the ETV Success Score in a mixed population of adult and pediatric patients

OBJECT

Endoscopic third ventriculostomy (ETV) has become the first line of treatment in obstructive hydrocephalus. The Toronto group (Kulkarni et al.) developed the ETV Success Score (ETVSS) to predict the clinical response following ETV based on age, previous shunt, and cause of hydrocephalus in a pediatric population. However, the use of the ETVSS has not been validated for a population comprising adults. The objective of this study was to validate the ETVSS in a "closed-skull" population, including patients 2 years of age and older.

METHODS

In this retrospective observational study, medical charts of all consecutive cases of ETV performed in two university hospitals were reviewed. The primary outcome, the success of ETV, was defined as the absence of reoperation or death attributable to hydrocephalus at 6 months. The ETVSS was calculated for all patients. Discriminative properties along with calibration of the ETVSS were established for the study population. The secondary outcome is the reoperation-free survival.

RESULTS

This study included 168 primary ETVs. The mean age was 40 years (range 3-85 years). ETV was successful at 6 months in 126 patients (75%) compared with a mean ETVSS of 82.4%. The area under the receiver operating characteristic curve was 0.61, revealing insufficient discrimination from the ETVSS in this population. In contrast, calibration of the ETVSS was excellent (calibration slope = 1.01), although the expected low numbers were obtained for scores < 70. Decision curve analyses demonstrate that ETVSS is marginally beneficial in clinical decision-making, a reduction of 4 and 2 avoidable ETVs per 100 cases if the threshold used on the ETVSS is set at 70 and 60, respectively. However, the use of the ETVSS showed inferior net benefit when compared with the strategy of not recommending ETV at all as a surgical option for thresholds set at 80 and 90. In this cohort, neither age nor previous shunt were significantly associated with unsuccessful ETV. However, better outcomes were achieved in patients with aqueductal stenosis, tectal compressions, and other tumor-associated hydrocephalus than in cases secondary to myelomeningocele, infection, or hemorrhage (p = 0.03).

CONCLUSIONS

The ETVSS did not show adequate discrimination but demonstrated excellent calibration in this population of patients 2 years and older. According to decision-curve analyses, the ETVSS is marginally useful in clinical scenarios in which 60% or 70% success rates are the thresholds for preferring ETV to CSF shunt. Previous history of CSF shunt and age were not associated with worse outcomes, whereas posthemorrhagic and postinfectious causes of the hydrocephalus were significantly associated with reduced success rates following ETV.

Endoscopic third ventriculocisternostomy in hydrocephalic children under 2 years of age: appropriate or not? A single-center retrospective cohort study

PURPOSE

Treating hydrocephalus can be difficult in children under the age of 2 years because a high amount of uncertainty exists as to which treatment to perform. In this retrospective cohort study, we analyzed children under the age of 2 years with hydrocephalus undergoing an endoscopic third ventriculocisternostomy (ETV) with respect to ETV outcome.

METHODS

In 59 consecutive patients under the age of 2 years, an ETV was performed between 1999 and 2010 at the Erasmus MC, Sophia Children's Hospital. Demographics, etiology of hydrocephalus, and radiological data were extracted retrospectively from the patients' medical records and operative reports and related to outcome. ETV Success Score (ETVSS) was used to retrospectively calculate the probability of success related to the actual outcome.

RESULTS

In this series, 42.4 % of patients had a successful ETV. The only statistically significant finding concerned age. The failed ETV patients appeared to be younger (0.52 ± 0.60 vs. 0.86 ± 0.56 year, p = 0.005), and when using a cutoff age of 6 months only, five out of 32 infants had a successful ETV (p = 0.002). Of the children with an arachnoid cyst, 57.1 % were treated successfully with an ETV. Of the five patients with a high probability of ETV success, four (80 %) were indeed successfully treated with ETV (p = 0.049).

CONCLUSIONS

Our data confirm the overall ineffectiveness of an ETV in children under the age of 6 months. Nevertheless, using the ETVSS is recommended to aid in the decision-making process even in patients under the age of 6 months.

Endoscopic third ventriculostomy

Endoscopic third ventriculostomy (ETV) is considered as a treatment of choice for obstructive hydrocephalus. It is indicated in hydrocephalus secondary to congenital aqueductal stenosis, posterior third ventricle tumor, cerebellar infarct, Dandy-Walker malformation, vein of Galen aneurism, syringomyelia with or without Chiari malformation type I, intraventricular hematoma, post infective, normal pressure hydrocephalus, myelomeningocele, multiloculated hydrocephalus, encephalocele, posterior fossa tumor and craniosynostosis. It is also indicated in block shunt or slit ventricle syndrome. Proper Pre-operative imaging for detailed assessment of the posterior communicating arteries distance from mid line, presence or absence of Liliequist membrane or other membranes, located in the prepontine cistern is useful. Measurement of lumbar elastance and resistance can predict patency of cranial subarachnoid space and complex hydrocephalus, which decides an ultimate outcome. Water jet dissection is an effective technique of ETV in thick floor. Ultrasonic contact probe can be useful in selected patients. Intra-operative ventriculo-stomography could help in confirming the adequacy of endoscopic procedure, thereby facilitating the need for shunt. Intraoperative observations of the patent aqueduct and prepontine cistern scarring are predictors of the risk of ETV failure. Such patients may be considered for shunt surgery. Magnetic resonance ventriculography and cine phase contrast magnetic resonance imaging are effective in assessing subarachnoid space and stoma patency after ETV. Proper case selection, post-operative care including monitoring of ICP and need for external ventricular drain, repeated lumbar puncture and CSF drainage, Ommaya reservoir in selected patients could help to increase success rate and reduce complications. Most of the complications develop in an early post-operative, but fatal complications can develop late which indicate an importance of long term follow up.