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

Ventriculo - Gallbladder shunt

INTRODUCTION

Permanent liquor diversion is associated with a high risk of failure and often requires re-intervention. The ventriculo-gallbladder shunt (VGS) has been recognized as a last-resort alternative for treating hydrocephalus when the peritoneum or other distal sites are no longer suitable for receiving shunts. This article aims to report a case from a neurosurgery referral service in Brazil and review the literature on this issue.

METHODS

A systematic literature review was conducted in accordance with the PRISMA statement. The PubMed, Embase, and Web of Science databases were searched for data screening and extraction. The reported case was conducted with ethical approval from the neurosurgical hospital's ethics committee.

RESULTS

G.B.S, male, 43 years old, no comorbidities, who has been dealing with a 12-year history of hydrocephalus, with post-surgical chronic fungal meningitis. Two years ago, he underwent a ventriculoatrial shunt (VAS) placement due to multiple ventriculoperitoneal shunt (VPS) failures. Endocarditis was suspected, and the VAS was removed. As an alternative, VGS was implanted 6 months ago, and since then, there has been no need for a new system review. The gallbladder has an absorptive capacity of 1500 cc of liquid daily, which is more than the normal daily production of cerebrospinal fluid (CSF). Therefore, it is a good alternative when the ventriculoperitoneal shunt is not feasible due to postsurgical peritoneal adhesions or when there are contraindications for ventriculoatrial shunts.

CONCLUSION

VGS is an alternative for patients who cannot undergo the most common surgical interventions, such as VPS.

Ventricular CSF proteomic profiles and predictors of surgical treatment outcome in chronic hydrocephalus

BACKGROUND

By applying an unbiased proteomic approach, we aimed to search for cerebrospinal fluid (CSF) protein biomarkers distinguishing between obstructive and communicating hydrocephalus in order to improve appropriate surgical selection for endoscopic third ventriculostomy vs. shunt implants. Our second study purpose was to look for potential CSF biomarkers distinguishing between patients with adult chronic hydrocephalus benefitting from surgery (responders) vs. those who did not (non-responders).

METHODS

Ventricular CSF samples were collected from 62 patients with communicating hydrocephalus and 28 patients with obstructive hydrocephalus. CSF was collected in relation to the patients' surgical treatment. As a control group, CSF was collected from ten patients with unruptured aneurysm undergoing preventive surgery (vascular clipping).

RESULTS

Mass spectrometry-based proteomic analysis of the samples identified 1251 unique proteins. No proteins differed significantly between the communicating hydrocephalus group and the obstructive hydrocephalus group. Four proteins were found to be significantly less abundant in CSF from communicating hydrocephalus patients compared to control subjects. A PCA plot revealed similar proteomic CSF profiles of obstructive and communicating hydrocephalus and control samples. For obstructive hydrocephalus, ten proteins were found to predict responders from non-responders.

CONCLUSION

Here, we show that the proteomic profile of ventricular CSF from patients with hydrocephalus differs slightly from control subjects. Furthermore, we find ten predictors of response to surgical outcome (endoscopic third ventriculostomy or ventriculo-peritoneal shunt) in patients with obstructive hydrocephalus.

Factors affecting endoscopic third ventriculostomy success in adults

BACKGROUND

Endoscopic third ventriculostomy (ETV) is a standard treatment in hydrocephalus of certain aetiologies. The most widely used predictive model is the ETV success score. This is frequently used to predict outcomes following ETV in adult patients; however, this was a model developed in paediatric patients with often distinct aetiologies of hydrocephalus. The aim of this study was to assess the predictive value of the model and to identify factors that influence ETV outcomes in adults.

METHODS

A retrospective study design was used to analyse consecutive patients who underwent ETV at a tertiary neurosurgical centre between 2012 and 2020. Observed ETV outcomes at 6 months were compared to pre-operative predicted ETV success scores. A multivariable Bayesian logistic regression analysis was used to determine the factors that best predicted ETV success and those factors that were redundant.

RESULTS

A total of 136 patients were analysed during the 9-year study. Thirty-one patients underwent further cerebrospinal fluid diversion within 6 months. The overall ETV success rate was 77%. Observed ETV outcomes corresponded well with predicted outcomes using the ETV success score for the higher scores, but less well for lower scores. Location of obstruction at the aqueduct irrespective of aetiology was the best predictor of success with odds of 1.65 of success. Elective procedures were also associated with higher success compared to urgent ones, whereas age under 70, nature and location of obstructive lesion (other than aqueductal) did not influence ETV success.

CONCLUSION

ETV was successful in three-quarters of adult patient with hydrocephalus within 6 months. Obstruction at the level of the aqueduct of any aetiology was a good predictor of ETV success. Clinicians should bear in mind that adult hydrocephalus responds differently to ETV compared to paediatric hydrocephalus, and more research is required to develop and validate an adult-specific predictive tool.

Agenesis of the right internal carotid artery and aqueductal stenosis in a child with hydrocephalus, the role of endoscopic third ventriculostomy: a case report

Agenesis of the internal carotid artery (aICA) is a rare congenital vascular condition that can affect one or both sides of the patient. Most patients remain asymptomatic, but ischemic/hemorrhagic stroke, intracranial aneurysm, and other neurologic findings can occur. CT scan can demonstrate the absence of the bony carotid canal and helps to differentiate a complete aICA from aplasia or hypoplasia. The association of aICA and aqueductal stenosis (AS) has never been reported in the literature. We report the case of a 9-year-old with agenesis of the right ICA associated with AS and hydrocephalus, which was treated successfully with an endoscopic third ventriculostomy (ETV). We review the literature looking for the association of the clinical findings and the evolution of the patient.

Endoscopic third ventriculostomy for noncommunicating hydrocephalus by vertebrobasilar dolichoectasia: A case report

Background:

Vertebrobasilar dolichoectasia (VBD) is a vasculopathy characterized by the elongation, widening, and tortuosity of a cerebral artery. Rarely, hydrocephalus results when the extended basilar artery impairs communication of the cerebral ventricle and cerebrospinal fluid dynamics. We experienced such a case when a patient underwent endoscopic third ventriculostomy (ETV) for noncommunicating hydrocephalus with VBD.

Case Description:

A 54-year-old man presented with cognitive dysfunction and was diagnosed with VBD by magnetic resonance imaging (MRI). Seven years later, he exhibited subacute impaired consciousness due to acute noncommunicating hydrocephalus, undergoing external ventricular drainage (EVD) that improved consciousness. After EVD removal, the noncommunicating hydrocephalus did not recur; however, 7 months later, subacute consciousness impairment due to noncommunicating hydrocephalus was again observed. MRI showed a significant dilation of both lateral ventricles and ballooning of the third ventricle while the right posterior cerebral artery shifted slightly posteriorly. The patient underwent ETV and clinical symptoms improved. One year after the treatment, MRI observed a patent ETV fenestration and no deleterious changes in clinical symptoms were observed.

Conclusion:

ETV can be an effective treatment for the noncommunicating hydrocephalus with VBD when performed with preoperative assessment of vascular anatomy and attention to vascular injury.

Idiopathic Aqueductal Stenosis: Late Neurocognitive Outcome in ETV Operated Adult Patients

Objective

The aim of the present study is to evaluate a neurocognitive outcome in patients affected by late-onset idiopathic aqueductal stenosis (LIAS) who underwent endoscopic third ventriculostomy (ETV).

Materials and Methods

A prospective study was conducted between January 2015 and December 2017 in a series of 10 consecutive adult patients referred to the Neurosurgery Department of IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy. All the adult patients admitted with absence of CSF flow through the aqueduct in phase-contrast (PC)—MRI sequences or a turbulence void signal in T2—weighted images in midsagittal thin-slice MR sequences underwent a specific neuroradiological, neurological, and neurocognitive assessment pre- and postoperatively.

Results

All patients affected by gait and sphincter disturbances improved after ETV. Attentive and executive functions as well as visuo-spatial memory and verbal executive functions improved in several patients. Similarly, the affective and behavioral scales improved in almost 50% of the patients. No major complications have been recorded, and no patients required a second surgery for shunt placement.

Conclusion

Endoscopic third ventriculostomy represents a safe and effective surgical procedure for the treatment of LIAS. In addition to neurological improvement, we demonstrated also postoperative neurocognitive improvement mainly in attentive and executive functions, visuo-spatial memory, verbal executive functions, and behavioral and affective domains.

A bi-foraminal craniometric-guided approach to endoscopic third ventriculostomy and biopsy of a pineal tumour

Background:

Pineal tumors are very rarely encountered, with an incidence of <1% of intracranial lesions in adults. Life-threatening hydrocephalus due to obstruction of the third ventricle can result from the location of these tumours. Endoscopic third ventriculostomy (ETV) and tumor biopsy is a safe and feasible strategy, particularly if the tumor appears benign. This mitigates the high risks of uncontrollable venous bleeding from open and stereotactic biopsies. While typically performed using either ipsilateral single or dual bur holes, the location of the tumor may require modifications to the standard endoscopic techniques.

Case Description:

A 55-year-old male presented with signs of intracranial hypertension and was found to have obstructive hydrocephalus due to a pineal tumour. The tumour displayed a right-sided dominance when the pre-operative imaging was assessed, which would risk forniceal injury if biopsied via a right-sided burr hole. Craniometric measurements revealed a superior trajectory to the tumour via the left foramen of Monro. A biforaminal approach was performed, with a traditional ETV using a right coronal bur hole and biopsy via a left frontal bur hole. This minimized forniceal stretching and allowed a safe biopsy.

Conclusion:

The bi-foraminal approach has not been widely described in the literature but can potentially avoid morbidity with biopsy in patients with right-sided pineal tumours. We believe this technique should be considered, particularly in low-resource settings where neuroendoscopy is not commonly done, and where the use of ipsilateral single or dual-bur holes may lead to forniceal injury.

Cognitive and gait outcomes after primary endoscopic third ventriculostomy in adults with chronic obstructive hydrocephalus

OBJECTIVE

The object of this study was to determine the short- and long-term efficacy of primary endoscopic third ventriculostomy (ETV) on cognition and gait in adults with chronic obstructive hydrocephalus.

METHODS

Patients were prospectively accrued through the Adult Hydrocephalus Clinical Research Network patient registry. Patients with previously untreated congenital or acquired obstructive hydrocephalus were included in this study. Gait velocity was assessed using a 10-m walk test. Global cognition was assessed with the Montreal Cognitive Assessment (MoCA). Only patients with documented pre- and post-ETV gait analysis and/or pre- and post-ETV MoCA were included.

RESULTS

A total of 74 patients had undergone primary ETV, 42 of whom were analyzed. The remaining 32 patients were excluded, as they could not complete both pre- and post-ETV assessments. The mean age of the 42 patients, 19 (45.2%) of whom were female, was 51.9 ± 17.1 years (range 19-79 years). Most patients were White (37 [88.1%]), and the remainder were Asian. Surgical complications were minor. Congenital etiologies occurred in 31 patients (73.8%), with aqueductal stenosis in 23 of those patients (54.8%). The remaining 11 patients (26.2%) had acquired cases. The gait short-term follow-up cohort (mean 4.7 ± 4.1 months, 35 patients) had a baseline median gait velocity of 0.9 m/sec (IQR 0.7-1.3 m/sec) and a post-ETV median velocity of 1.3 m/sec (IQR 1.1-1.4 m/sec). Gait velocity significantly improved post-ETV with a median within-patient change of 0.3 m/sec (IQR 0.0-0.6 m/sec, p < 0.001). Gait velocity improvements were sustained in the long term (mean 14 ± 2.8 months, 12 patients) with a baseline median velocity of 0.7 m/sec (IQR 0.6-1.3 m/sec), post-ETV median of 1.3 m/sec (IQR 1.1-1.7 m/sec), and median within-patient change of 0.4 m/sec (IQR 0.2-0.6 m/sec, p < 0.001). The cognitive short-term follow-up cohort (mean 4.6 ± 4.0 months, 38 patients) had a baseline median MoCA total score (MoCA TS) of 24/30 (IQR 23-27) that improved to 26/30 (IQR 24-28) post-ETV. The median within-patient change was +1 point (IQR 0-2 points, p < 0.001). However, this change is not clinically significant. The cognitive long-term follow-up cohort (mean 14 ± 3.1 months, 15 patients) had a baseline median MoCA TS of 23/30 (IQR 22-27), which improved to 26/30 (IQR 25-28) post-ETV. The median within-patient change was +2 points (IQR 1-3 points, p = 0.007), which is both statistically and clinically significant.

CONCLUSIONS

Primary ETV can safely improve symptoms of gait and cognitive dysfunction in adults with chronic obstructive hydrocephalus. Gait velocity and global cognition were significantly improved, and the worsening of either was rare following ETV.

Risk factors for pediatric surgical site infection following neurosurgical procedures for hydrocephalus: a retrospective single-center cohort study

Background

Infection is a major complication following cerebral spinal fluid (CSF) diversion procedures for hydrocephalus. However, pediatric risk factors for surgical site infection (SSI) are currently not well defined. Because a SSI prevention bundle is increasingly introduced, the purpose of this study was to evaluate risk factors associated with SSIs following CSF diversion surgeries following a SSI bundle at a single quaternary care pediatric hospital.

Methods

We performed a retrospective cohort study of patients undergoing CSF diversion procedures from 2017 to 2019. SSIs were identified prospectively through continuous surveillance. We performed unadjusted logistic regression analyses and univariate analyses to determine an association between SSIs and patient demographics, comorbidities and perioperative factors to identify independent risk factors for SSI.

Results

We identified a total of 558 CSF diversion procedures with an overall SSI rate of 3.4%. The SSI rates for shunt, external ventricular drain (EVD) placement, and endoscopic third ventriculostomy (ETV) were 4.3, 6.9 and 0%, respectively. Among 323 shunt operations, receipt of clindamycin as perioperative prophylaxis and presence of cardiac disease were significantly associated with SSI (O.R. 4.99, 95% C.I. 1.27–19.70, p = 0.02 for the former, and O.R. 7.19, 95% C.I. 1.35–38.35, p = 0.02 for the latter). No risk factors for SSI were identified among 72 EVD procedures.

Conclusion

We identified receipt of clindamycin as perioperative prophylaxis and the presence of cardiac disease as risk factors for SSI in shunt procedures. Cefazolin is recommended as a standard antibiotic for perioperative prophylaxis. Knowing that unsubstantiated beta-lactam allergy label is a significant medical problem, efforts should be made to clarify beta-lactam allergy status to maximize the number of patients who can receive cefazolin for prophylaxis before shunt placement. Further research is needed to elucidate the mechanism by which cardiac disease may increase SSI risk after shunt procedures.

Endoscopic Endonasal Transsphenoidal Approach for Third Ventriculostomy in the Management of Obstructive Hydrocephalus

ABSTRACT

Endoscopic third ventriculostomy (ETV) is a safe and effective method for the management of obstructive hydrocephalus. Traditional approach is a transfrontal trajectory through the foramen of Monro to access and open the third ventricle floor. Though endoscopic endonasal transsphenoidal approach (EETA) for pituitary and skull base tumors has become increasingly popular, no published literature has explored its utility in performing an ETV. Here, the authors reported a successful ETV for obstructive hydrocephalus through the EETA. A 57-year-old male presenting with progressive headache and gait disturbance for 3 months was diagnosed with obstructive hydrocephalus. Brain MRI revealed an obstruction of cerebrospinal fluid (CSF) flow at the cerebral aqueduct and supratentorial hydrocephalus, accompanied with dilatation and downward herniation of the third ventricle floor. Considering the displacement of the third ventricle floor and the indication for surgery, an ETV was successfully performed through the EETA. No postoperative complication was observed. Both radiological and clinical evaluation postoperatively confirmed ETV success with decreased ventricular size, increased CSF flow across the floor of the third ventricle, and improved clinical signs. EETA is a feasible approach for ETV in selected cases of obstructive hydrocephalus. This approach provides a short trajectory to directly visualize and open the Liliequist's membrane and the displaced floor of the third ventricle, while minimizes damage to normal brain tissue. Skull base repair with nasoseptal flap ensures the success rate by preventing postoperative CSF leak and infection.

The role of the Liliequist membrane in the third ventriculostomy

Endoscopic third ventriculostomy (ETV) is a hydrocephalus treatment procedure that involves opening the Liliequist membrane (LM). However, LM anatomy has not been well-studied neuroendoscopically, because approach angles differ between descriptive and microsurgical anatomical explorations. Discrepancies in ETV efficacy, especially among children age 2 and younger, may be due to incomplete LM opening. The objective of this study was to characterize the LM anatomically from a neuroendoscopic perspective to better understand the impact of anatomical features during LM ostomy and the ETV success rate. Additionally, the ETV success score was tested to predict patient outcome after the intraoperatively difficult opening of LM. Fifty-four patients who underwent ETV were prospectively analyzed with a mean follow-up of 53.1 months (1-90 months). The ETV technical parameters of difficulty were validated by seven expert neurosurgeons. The pediatric population (44) of this study represents the majority of patients (81.4%). The overall ETV success rate was 68.5%. Anomalies on the IIIVT floor resulted in an increased rate of ETV failure. The IIIVT was anomalous, and LM was thick in 33.3% of cases. Fenestration of LM was difficult in 39% of cases, and the LM and TC were opened separately in 55.6% of cases. The endoscopic third ventriculostomy success score (ETVSS) accurately predicted the level of difficulty opening the LM (p = 0.012), and the group with easy opening presented greater durability in ETV success. Neurosurgeons should be aware of the difficulty level of the overture of LM during ETV and its impact on long-term ETV effectiveness.

External validation of the ETV success score in 313 pediatric patients: a Brazilian single-center study

The endoscopic third ventriculostomy (ETV) success score (ETVSS) was developed to predict the success rate of ETV at 6 months. In this study, the authors assessed the performance of this score for > 6 months, i.e., at 12 months, and provided external validation in Brazilian children. All children undergoing first ETV (without choroid plexus cauterization) at a Brazilian single institution for > 20 years were included in the study. The ETVSS was retrospectively calculated for each patient and compared with the actual success of the procedure observed at 6 and 12 months after the procedure. A total of 313 eligible children underwent initial ETV, 34.18% of whom had undergone shunt placement before ETV. The most common etiologies were aqueductal stenosis (45%) and non-tectal brain tumors (20.8%). ETV was successful at 6 months in 229 patients (73.16%) compared with the 61.3% predicted by the ETVSS. The overall actual success rate observed at 1 year after ETV was 65.1% (204 patients). The area under the receiver operating characteristic curve was 0.660 at 6 months and 0.668 at 1 year, which suggested a tendency for the ETVSS to underestimate the actual success rate of ETV at both timepoints. The ETVSS showed good success prediction in accordance with the actual ETV success rate and proved to be useful during the decision-making process of ETV.

Endoscopic management of pineal cyst-associated aqueductal stenosis

OBJECT

The purpose of this study was to evaluate whether endoscopic third ventriculostomy (ETV) and endoscopic cyst fenestration are effective minimally invasive alternatives to a craniotomy with cyst resection for the treatment of symptomatic pineal cyst-associated aqueductal stenosis.

METHODS

Sixteen patients with symptomatic pineal cysts were operatively managed endoscopically and these cases were retrospectively reviewed. There were 12 females and 4 males. The median age at the time of surgery was 31 years (range 3 to 62 years).

RESULTS

All patients presented with symptoms and imaging consistent with elevated intracranial pressure. The median maximum cyst diameter was 15 mm (range 10 mm to 27 mm). In all cases, there was mass effect on the tectum that resulted in effacement of the cerebral aqueduct and ventriculomegaly was present in 38% of cases. ETV was performed in 15 patients. Cyst fenestration was performed in 2 patients, one of which also had an ETV. Resolution of symptoms was achieved in 81% of patients with a median follow-up of 13 months.

CONCLUSION

This study showed that ETV is effective for symptomatic pineal cyst-associated aqueductal stenosis. Patients can be symptomatic without overt ventriculomegaly and normal ventricular volume does not preclude safe endoscopic management. Endoscopic cyst fenestration is recommended if a Perinaud syndrome is present or if ETV is not feasible.

ETV in infancy and childhood below 2 years of age for treatment of hydrocephalus

PURPOSE

Age and etiology play a crucial role in success of endoscopic third ventriculostomy (ETV) as a treatment of obstructive hydrocephalus. Outcome is worse in infants, and controversies still exist whether ETV is superior to shunt placement. We retrospectively analyzed 70 patients below 2 years from 4 different centers treated with ETV and assessed success.

METHODS

Children < 2 years who received an ETV within 1994-2018 were included. Patients were classified according to age and etiology; < 3, 4-12, and 13-24 months, etiologically; aqueductal stenosis, post-hemorrhagic-hydrocephalus (PHH), tumor-related, fourth ventricle outflow obstruction, with Chiari-type II and following CSF infection. We investigated statistically the predictors for ETV success through computing Kaplan-Meier estimates using patient's follow-up time and time to ETV failure.

RESULTS

We collected 70 patients. ETV success rate was 41.4%. The highest rate was in tumor-related hydrocephalus and fourth ventricle outlet obstruction (62.5%, 60%) and the lowest rate was in Chiari-type II and following infection (16.7%, 0%). The below 3 months age group showed relatively lower success rate (33.3%) in comparison to older groups which showed similar results (46.4%, 46.6%). Statistically, a previous VP shunt was a predictor for failure (p value < 0.05).

CONCLUSION

Factors suggesting a high possibility of failure were age < 3 months and etiology such as Chiari-type II or following infection. Altered CSF dynamics in patients with PHH and under-developed arachnoid villi may play a role in ETV failure. We do not recommend ETV as first line in children < 3 months of age or in case of Chiari II or following infection.

Prediction of endoscopic third ventriculostomy (ETV) success with preoperative third ventricle floor bowing (TVFB): a supplement to ETV success score

Preoperative judgement of which children is likely to benefit from endoscopic third ventriculostomy (ETV) is still the most difficult challenge. This study aimed to compare the efficiency of third ventricular floor bowing (TVFB) and ETV success score (ETVSS) in selecting ETV candidates and achieve a better preoperative patient selection method for ETV based on our institutional experience. Children (≤ 16 years old) with newly diagnosed hydrocephalus treated with ETV between January 2013 and June 2018 were included in this prospective study. Patients with TVFB will receive ETV procedure in the pediatric subgroup of our department. ETVSS was calculated in every patient. The ETVSS predicted ETV success rate and the actual ETV success rate in our institution were compared and further analyzed. One hundred twenty-nine children with TVFB were enrolled in our study. The mean age at ETV was 5.84 ± 5.17 years (range, 0.04-16). Brain tumors, aqueductal stenosis, and inflammatory are the most common hydrocephalus etiologies. The most common complication was noninfectious fever (3.1%). During the average follow-up of 19.5 ± 14.95 months, twenty-five patients had depicted ETV failure. The actual ETV success rate (81%) in our study was higher than the success rate (69%) predicted by ETVSS. TVFB is a pragmatic, efficient, and simple model to predict the ETV outcome. We suggest that for hydrocephalic patients with preoperative third ventricular floor bowing, ETV should be the first-treatment choice regardless of the ETV success score. And for patients without such sign, ETVSS should be applied to select ETV candidates.

Predicting endoscopic third ventriculostomy success in adult hydrocephalus: preliminary assessment of a modified ETV success score for adults (ETVSS-A) in a series of 47 patients

BACKGROUND

Endoscopic third ventriculostomy is an established treatment for noncommunicating hydrocephalus. In carefully selected patients, it can be adopted for the management of communicating variant; however controversy exists in regards to the definition of the appropriate candidates. Predictive score of Endoscopic Third Ventriculostomy Success (ETVSS) has been reported for pediatric and mixed populations only. Our purpose was to define a ETV success score for adult population (ETVSS-A), measuring the strength of correlation between preoperative score retrospectively evaluated and the success rates achieved in a class of adult patients.

METHODS

A retrospective analysis of 47 cases which received ETV procedure at our Institution between 2015 and 2018 was run. Demographic data,clinical history,preoperative and postoperative signs were reviewed and ETVSS-A was calculated. Thereafter ETVSS-A results were compared with the actual success rates.

RESULTS

29 patients(61,7%) presented unchanged or improvedclinical status with a mean ETVSS-A of 54.5%;18 patients(38,3%) worsened with mean ETVSS-A of 37,7%. We found that age,type of hydrocephalus and symptoms of admission are each apart important factors in predicting ETV success:older patients and those with non-obstructive hydrocephalus had the lowest predicted ETV success. In patients in whom ETV was actually successful, the pre-operative ETVSS-A was significantly higher as compared to those patients in whom we observed a poor surgical outcome.

CONCLUSIONS

From the results of this series, though small and retrospectively analyzed, it seems that ETVSS-A can be considered as a useful instrument to help neurosurgeon in predicting the ETV success and though define a more accurate surgical strategy in cases of hydrocephalus. Wider series and prospective studies are attended to validate these preliminary results.

Outcome of single-trajectory rigid endoscopic third ventriculostomy and biopsy in the management algorithm of pineal region tumors: a case series and review of the literature

BACKGROUND

Tumors within the pineal region represent 1.5 to 8.5% of the pediatric brain tumors and 1.2% of all brain tumors. A management algorithm has been proposed in several publications. The algorithm includes endoscopic third ventriculostomy (ETV) and biopsy in cases presenting with hydrocephalus. In this series, we are presenting the efficacy of a single-trajectory approach for both ETV and biopsy.

METHODS

Eleven cases were admitted to Alexandria main university hospital from 2013 to 2016 presenting with pineal region tumors and hydrocephalus. Mean age at diagnosis was 11 years (1-27 years). All cases had ETV and biopsy using rigid ventriculoscope through a single trajectory from a burr hole planned on preoperative imaging. Follow-up period was 7-48 months.

RESULTS

All 11 cases presented with hydrocephalus and increased intracranial pressure manifestations. Histopathological diagnosis was successful in 9 out of 11 cases (81.8%). Three cases were germ-cell tumors, two cases were pineoblastomas, two cases were pilocytic astrocytomas, and two cases were grade 2 tectal gliomas. Five of the ETV cases (45.5%) failed and required VPS later on. Other complications of ETV included one case of intraventricular hemorrhage and a case with tumor disseminated to the basal cisterns.

CONCLUSION

In our series, we were able to achieve ETV and biopsy through a single trajectory and a rigid endoscope with results comparable to other studies in the literature.

The Results of Neuroendoscopic Surgery in Patients with Posttraumatic and Posthemorrhagic Hydrocephalus

BACKGROUND

Posttraumatic hydrocephalus (PTH) and posthemorrhagic hydrocephalus (PHH) were previously considered not suitable for neuroendoscopic treatment. New hydrocephalus theories support possible successful neuroendoscopy in such patients.

METHODS

This study presents the results of neuroendoscopy in PTH and PHH with a background analysis. From 130 hydrocephalic patients after neuroendoscopic surgeries, 35 cases with PTH (n = 11) or PHH (n = 24; acute: n = 9, subacute: n = 10, chronic: n = 5) were found. The success rate (Glasgow Outcome Scale [GOS] score 4 or 5 without shunt) and clinical outcome (GOS score) of endoscopic third ventriculostomy (ETV) were analyzed. During the study period, 34 patients had ventriculoperitoneal shunts implanted, including 2 PTH and 5 PHH patients (all chronic).

RESULTS

The success rate of ETV in PTH was 54.5%. In acute PHH, the success rate was 33.3%, 42.8% after excluding devastating hematomas. A post-ETV shunt was implanted in 1 patient (massive subarachnoid hemorrhage [SAH]) with final GOS score of 5. In subacute cases, the ETV success rate was 40% (no post-ETV shunts). In chronic PHH, only 1 patient with a GOS score of 5 was shunt-free (20%). The cause of ETV failure was massive SAH. Low final GOS score was caused by the extent of intracerebral bleeding or extracranial problems. The main indications for primary shunt implantation in PTH and PHH were infectious complications. The rate of good outcomes was 0% in PTH and 40% in PHH.

CONCLUSIONS

The best results of neuroendoscopy were achieved in PTH and acute PHH. ETV failures were associated with massive SAH; arachnoid cistern blockage and scarring precludes ETV success.

Endoscopic third ventriculostomy and repeat endoscopic third ventriculostomy in pediatric patients: the Dutch experience

OBJECTIVE After endoscopic third ventriculostomy (ETV), some patients develop recurrent symptoms of hydrocephalus. The optimal treatment for these patients is not clear: repeat ETV (re-ETV) or CSF shunting. The goals of the study were to assess the effectiveness of re-ETV relative to initial ETV in pediatric patients and validate the ETV success score (ETVSS) for re-ETV. METHODS Retrospective data of 624 ETV and 93 re-ETV procedures were collected from 6 neurosurgical centers in the Netherlands (1998-2015). Multivariable Cox proportional hazards modeling was used to provide an adjusted estimate of the hazard ratio for re-ETV failure relative to ETV failure. The correlation coefficient between ETVSS and the chance of re-ETV success was calculated using Kendall's tau coefficient. Model discrimination was quantified using the c-statistic. The effects of intraoperative findings and management on re-ETV success were also analyzed. RESULTS The hazard ratio for re-ETV failure relative to ETV failure was 1.23 (95% CI 0.90-1.69; p = 0.20). At 6 months, the success rates for both ETV and re-ETV were 68%. ETVSS was significantly related to the chances of re-ETV success (τ = 0.37; 95% bias corrected and accelerated CI 0.21-0.52; p < 0.001). The c-statistic was 0.74 (95% CI 0.64-0.85). The presence of prepontine arachnoid membranes and use of an external ventricular drain (EVD) were negatively associated with treatment success, with ORs of 4.0 (95% CI 1.5-10.5) and 9.7 (95% CI 3.4-27.8), respectively. CONCLUSIONS Re-ETV seems to be as safe and effective as initial ETV. ETVSS adequately predicts the chance of successful re-ETV. The presence of prepontine arachnoid membranes and the use of EVD negatively influence the chance of success.

Failure of ETV in patients with the highest ETV success scores

OBJECTIVE Endoscopic third ventriculostomy (ETV) is a surgical alternative to placing a CSF shunt in certain patients with hydrocephalus. The ETV Success Score (ETVSS) is a reliable, simple method to estimate the success of the procedure by 6 months of postoperative follow-up. The highest score is 90, estimating a 90% chance of the ETV effectively treating hydrocephalus without requiring a shunt. Treatment with ETV fails in certain patients, despite their being the theoretically best candidates for the procedure. In this study the authors attempted to identify factors that further predicted success in patients with the highest ETVSSs. METHODS A retrospective review was performed of all patients treated with ETV at 3 institutions. Demographic, radiological, and clinical data were recorded. All patients by definition were older than 1 year, had obstructive hydrocephalus, and did not have a prior shunt. Failure of ETV was defined as the need for a shunt by 1 year. The ETV was considered a success if the patient did not require another surgery (either shunt placement or a repeat endoscopic procedure) by 1 year. A statistical analysis was performed to identify factors associated with success or failure. RESULTS Fifty-nine patients met the entry criteria for the study. Eleven patients (18.6%) required further surgery by 1 year. All of these patients received a shunt. The presenting symptom of lethargy statistically correlated with success (p = 0.0126, odds ratio [OR] = 0.072). The preoperative radiological finding of transependymal flow (p = 0.0375, OR 0.158) correlated with success. A postoperative larger maximum width of the third ventricle correlated with failure (p = 0.0265). CONCLUSIONS The preoperative findings of lethargy and transependymal flow statistically correlated with success. This suggests that the best candidates for ETV are those with a relatively acute elevation of intracranial pressure. Cases without these findings may represent the failures in this highly selected group.

First 60 fetal in-utero myelomeningocele repairs at Saint Louis Fetal Care Institute in the post-MOMS trial era: hydrocephalus treatment outcomes (endoscopic third ventriculostomy versus ventriculo-peritoneal shunt)

INTRODUCTION

The published results of the Management of Myelomeningocele Study (MOMS) trial in 2011 showed improved outcomes (reduced need for shunting, decreased incidence of Chiari II malformation, and improved scores of mental development and motor function) in the fetal prenatal repair group compared to the postnatal group. Historically, endoscopic third ventriculostomy (ETV) remains as a controversial hydrocephalus treatment option with high failure rates in pediatric patients with a history of myelomeningocele (MMC). We report hydrocephalus treatment outcomes in the fetal in-utero myelomeningocele repair patients who underwent repair at our Saint Louis Fetal Care Institute following the MOMS trial. We looked carefully at ETV outcomes in this patient population and we identified risk factors for failure.

METHODS

At our Saint Louis Fetal Care Institute, we followed the maternal and fetal inclusion and exclusion criteria used by the MOMS trial. The records of our first 60 fetal MMC repairs performed at our institute between 2011 and 2017 were examined. We retrospectively reviewed the charts, prenatal fetal magnetic resonance imaging (MRI) and ultrasound (US) imaging findings, postnatal brain MRI, and Bayley neurodevelopment testing results for infants and children who underwent surgical treatment of symptomatic hydrocephalus (VP shunt versus ETV). Multiple variables possibly related to ETV failure were considered for identifying risk factors for ETV failure.

RESULTS

Between May 2011 and March 2017, 60 pregnant female patients underwent the prenatal MMC repair for their fetuses between 20 and 26 weeks' gestational age (GA) utilizing the standard hysterotomy for exposure of the fetus, and microsurgical repair of the MMC defect. All MMC defects underwent successful in-utero repair, with subsequent progression of the pregnancy. At the time of this study, 58 babies have been born, 56 are alive since there were 2 mortalities in the neonatal period due to prematurity. One patient was excluded given lack of consent for research purposes. From the remaining 55 patient included in this study, a total of 30 infants and toddlers underwent treatment of hydrocephalus (ETV and VPS groups). Twenty-five patients underwent ETV (24 primary ETV and 1 after shunt failure). Nineteen patients underwent shunt placements (6 primary/13 after ETV failure). Mean GA at time of MMC repair for the ETV group was 24 + 6/7 weeks (range 22 + 4/7 to 25 + 6/7). Mean follow up for patients who had a successful ETV was 17.25 months (range 4-57 months). Bayley neurodevelopmental testing results were examined pre- and post-ETV. Overall ETV success rate was 11/24 (45.8%) at the time of this study. The total number of patients who underwent shunt placement was 19/55 (34.5%), while shunting rate was 40% in the MOMS trial. Using a simple logistic regression analysis to identify predictors of ETV failure, ETV age ≤6 months and gestational age ≥23 weeks at repair of myelomeningocele were significant predictors for ETV failure while in-utero ventricular stability ≤4 mm and in-utero ventricular size post-repair ≤15.5 mm were significant predictors for ETV success. None of the listed variables independently predicted classification into ETV success versus ETV failure groups when entered into multiple logistic regression analysis.

CONCLUSIONS

ETV, as an alternative to initial shunting, may continue to show promising results for treating fetal MMC repair patient population who present with symptomatic hydrocephalus during infancy and early childhood. Although our overall CSF diversion rate (ETV and VPS groups) in our fetal MMC group is higher than the MOMS trial, our shunting rate is lower given our higher incidence of patients with successful ETV. To our knowledge, this is the largest reported ETV series in patients who underwent fetal MMC repair. ETV deserves a closer look in the setting of improved hindbrain herniation in fetal in-utero MMC repair patients. In our series, young age (less than 6 months) and late GA at time of fetal MMC repair (after 23 weeks GA) were predictors for ETV failure, while in-utero stability of ventricular size (less than 4 mm) and in-utero ventricular size post-repair ≤15.5 mm were predictors for ETV success. Larger series and potential prospective randomized studies are required for further evaluation of risk factors for ETV failure in the fetal MMC patient population.

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.

Endoscopic third ventriculostomy for treatment of adult hydrocephalus: long-term follow-up of 163 patients

OBJECTIVE The efficacy of endoscopic third ventriculostomy (ETV) for the treatment of pediatric hydrocephalus has been extensively reported in the literature. However, ETV-related long-term outcome data are lacking for the adult hydrocephalus population. The objective of the present study was to assess the role of ETV as a primary or secondary treatment for hydrocephalus in adults. METHODS The authors performed a retrospective chart review of all adult patients (age ≥ 18 years) with symptomatic hydrocephalus treated with ETV in Calgary, Canada, over a span of 20 years (1994-2014). Patients were dichotomized into a primary or secondary ETV cohort based on whether ETV was the initial treatment modality for the hydrocephalus or if other CSF diversion procedures had been previously attempted respectively. Primary outcomes were subjective patient-reported clinical improvement within 12 weeks of surgery and the need for any CSF diversion procedures after the initial ETV during the span of the study. Categorical and actuarial data analysis was done to compare the outcomes of the primary versus secondary ETV cohorts. RESULTS A total of 163 adult patients with symptomatic hydrocephalus treated with ETV were identified and followed over an average of 98.6 months (range 0.1-230.4 months). All patients presented with signs of intracranial hypertension or other neurological symptoms. The primary ETV group consisted of 112 patients, and the secondary ETV consisted of 51 patients who presented with failed ventriculoperitoneal (VP) shunts. After the initial ETV procedure, clinical improvement was reported more frequently by patients in the primary cohort (87%) relative to those in the secondary ETV cohort (65%, p = 0.001). Additionally, patients in the primary ETV group required fewer reoperations (p < 0.001), with cumulative ETV survival time favoring this primary ETV cohort over the course of the follow-up period (p < 0.001). Fifteen patients required repeat ETV, with all but one experiencing successful relief of symptoms. Patients in the secondary ETV cohort also had a higher incidence of complications, with one occurring in 8 patients (16%) compared with 2 in the primary ETV group (2%; p = 0.010), although most complications were minor. CONCLUSIONS ETV is an effective long-term treatment for selected adult patients with hydrocephalus. The overall ETV success rate when it was the primary treatment modality for adult hydrocephalus was approximately 87%, and 99% of patients experience symptomatic improvement after 2 ETVs. Patients in whom VP shunt surgery fails prior to an ETV have a 22% relative risk of ETV failure and an almost eightfold complication rate, although mostly minor, when compared with patients who undergo a primary ETV. Most ETV failures occur within the first 7 months of surgery in patients treated with primary ETV, but the time to failure is more prolonged in patients who present with failed previous shunts.

Assessing the Clinical Impact of Risk Prediction Models With Decision Curves: Guidance for Correct Interpretation and Appropriate Use

The decision curve is a graphical summary recently proposed for assessing the potential clinical impact of risk prediction biomarkers or risk models for recommending treatment or intervention. It was applied recently in an article in Journal of Clinical Oncology to measure the impact of using a genomic risk model for deciding on adjuvant radiation therapy for prostate cancer treated with radical prostatectomy. We illustrate the use of decision curves for evaluating clinical- and biomarker-based models for predicting a man's risk of prostate cancer, which could be used to guide the decision to biopsy. Decision curves are grounded in a decision-theoretical framework that accounts for both the benefits of intervention and the costs of intervention to a patient who cannot benefit. Decision curves are thus an improvement over purely mathematical measures of performance such as the area under the receiver operating characteristic curve. However, there are challenges in using and interpreting decision curves appropriately. We caution that decision curves cannot be used to identify the optimal risk threshold for recommending intervention. We discuss the use of decision curves for miscalibrated risk models. Finally, we emphasize that a decision curve shows the performance of a risk model in a population in which every patient has the same expected benefit and cost of intervention. If every patient has a personal benefit and cost, then the curves are not useful. If subpopulations have different benefits and costs, subpopulation-specific decision curves should be used. As a companion to this article, we released an R software package called DecisionCurve for making decision curves and related graphics.