Predictive factors associated with ventriculoperitoneal shunting after posterior fossa tumor surgery in children

Evaluating Linear Heuristics for Ventricular Volume in Healthy Adults Using a Fully Automated Algorithm: Implications for Defining the Normal

BACKGROUND AND OBJECTIVES

Linear metrics for ventricular volume play a large role in the rapid, approximate evaluation of ventricular volume. In this article, we automatically extract linear measures of ventricular volume to explore their correlation with lateral ventricular volume (LVV) in the healthy adult population and comprehensively define normal values.

METHODS

We automatically extract Evans' ratio (ER), Frontal-Occipital Horn Ratio (FOHR), and anteroposterior lateral ventricle index (ALVI) from an open MRI data set of healthy adults ( https://brain-development.org/ixi-dataset/ ). Indices have been correlated with corresponding LVVs and lateral ventricular volumes divided by supratentorial brain volumes. Spearman rank correlation was used to compare strength of correlation.

RESULTS

ER shows correlation with lateral ventricle volume based on sex (r = 0.58; men, r = 0.65; women P < .001), including when controlling for supratentorial volume (r = 0.57; men, r = 0.63). ER did not profoundly correlate with age (r = 0.29, men; r = 0.35, women; P < .001) and seemed normally distributed around 0.25. ALVI showed strong correlation with LVV with only slight gender differences (r = 0.83, men; r = 0.84, women) and LVV to supratentorial cortical volume ratio (r = 0.9, men; r = 0.86, women). FOHR was also normally distributed around a value of 0.37 and showed moderate correlation with LVV (r = 0.68, men; r = 0.73, women) and LVV to supratentorial cortical volume ratio (r = 0.69, men; r = 0.74, women).

CONCLUSION

ALVI is a newer index with strong correlation with LVV and has strong potential for clinical use. Both FOHR and ER show moderate correlation with LVV. Reference values for linear estimates of ventricular volume may help clinicians better identify patients with pathological ventriculomegaly.

Validating the modified Canadian Preoperative Prediction Rule for Hydrocephalus for accurate hydrocephalus prediction in a statewide pediatric brain tumor cohort

PURPOSE

The modified Canadian Preoperative Prediction Rule for Hydrocephalus (mCPPRH) was developed to predict the need for permanent CSF diversion in children with posterior fossa tumors (PFT). This study aimed to externally validate the mCPPRH in a cohort of 113 pediatric patients with PFTs.

METHODS

We conducted a retrospective analysis, calculating the mCPPRH score for each patient and performing receiver operating characteristic (ROC) curve analysis to assess the tool's discriminative ability. Sensitivity, specificity, predictive values, and likelihood ratios were calculated using a cutoff score of ≥ 5. Multivariable logistic regression with bidirectional stepwise selection was used to evaluate individual components of the score. The mCPPRH components were modified and the performance of adjusted tools was compared to the original.

RESULTS

Of the 113 patients, 35 (31.0%) required permanent CSF diversion. The mCPPRH demonstrated acceptable discriminative ability (AUC = 0.701, 95% CI 0.608-0.795, p < 0.0003). Sensitivity was 34.1%, specificity 89.7%, positive predictive value 60%, and negative predictive value 75.3%. Initial regression identified no significant predictors. In stepwise regression, moderate-severe hydrocephalus independently predicted permanent CSF diversion (OR 6.37, 95% CI 1.71-41.55, p = 0.02). Increasing the age cutoff to < 5 years, removing tumor diagnosis, and modifying hydrocephalus weighting improved performance (AUC = 0.768, sensitivity 71.4%, specificity 75.6%).

CONCLUSIONS

The mCPPRH demonstrates acceptable discriminative ability (AUC 0.701) in our cohort, with particular utility in identifying low-risk patients. However, its poor sensitivity (34.1%) and variable predictor performance suggest that additional clinical factors should be considered for treatment planning, particularly in higher-risk cases. Further modification of mCPPRH components is suggested to improve its utility.

Transient and permanent hydrocephalus following resection of brain metastases located in the posterior fossa: incidence, risk factors and the necessity of perioperative external ventricular drainage placement

PURPOSE

Prophylactic insertion of an external ventricular drainage (EVD) prior to the resection of posterior fossa metastases (PFMs) is a common approach to address postoperative transient and permanent hydrocephalus. However, predicting surgery-related hydrocephalus in the preoperative phase continues to be a challenge. This study aims to analyze the incidence, preoperatively collectable risk factors and necessity of perioperative external ventricular drainage placement after posterior fossa metastasis surgery.

METHODS

All patients undergoing surgery for PFMs at the authors' neuro-oncological center between 2015 and 2021 were identified and assessed for postoperative hydrocephalus occurrence. Tumour volume, edema volume, and 4th ventricle volume were assessed on preoperative magnetic resonance imaging scans using the IntelliSpace Portal 5.0. A multivariable logistic regression analysis was performed to identify possible predictors for postoperative hydrocephalus occurrence.

RESULTS

Postoperative hydrocephalus occurred in 14 of the 130 identified PFM patients (11%). Multivariable analysis and receiver operating characteristic (ROC) analysis revealed a 4th -ventricle-to-tumor-volume ratio ≤ 0.02 (OR 33.1, 95% CI 3.8-284.3, p = 0.001), an edema-to- tumor-volume ratio ≤ 0.85 (OR 10.6, 95% CI 2.4-47.4, p = 0.002), an imaging-morphological contact to the 4th ventricle (OR 5, 95% CI 1.4-18, p = 0.013), and multiple intracranial metastases (OR 2.4, 95% CI 1-5.9, p = 0.045) as independent predictors for surgery-related postoperative hydrocephalus occurrence.

CONCLUSION

The present study identifies preoperatively detectable risk factors for the occurrence of postoperative hydrocephalus following surgery for PFMs. These findings may provide guidance in clinical decision-making regarding prophylactic EVD placement.

Clinical and radiologic criteria to predict endoscopic third ventriculostomy success in non-communicating pediatric hydrocephalus

OBJECTIVE

Endoscopic third ventriculocisternostomy (ETV) became the relevant treatment option for non-communicating pediatric hydrocephalus. ETV success was predicted in relation to age, diagnosis, and previous shunt implantation. Radiological factors are usually taken for indication decision-making. The aim of this study is to investigate radiological signs of non-communicating hydrocephalus for ETV success in a single-center retrospective analysis.

PATIENTS AND METHODS

ETV interventions were collected from a 10-year period (2010-2019) from our institution. Clinical patient characteristics such as prematurity, age, diagnosis, and previous shunt treatment and follow-up in terms of possible shunt implantation or revision surgeries were investigated. Radiological data was retrieved from the in-house PACS system to analyze preoperative signs for non-communicating hydrocephalus such as ventricular size, pressure gradients at the third ventricle, and any signs of obstruction from internal towards external cerebral spinal fluid communication. Fisher's test was used to demonstrate the significance of each individual predictor. A multivariable model was built using the backward elimination method with multiple logistic regression.

RESULTS

From 136 ETV interventions, 95 met the inclusion criteria (age < 18 years; > 6-month follow-up; MR image data availability, treatment goal for shunt independence). In chi-square statistical evaluation of single parameters age > 6 months (OR 32.5; 95% CI 4.8-364), ventricular width (FOHR < 0.56; OR 6.1; 95% CI 2.2-16.3) and non-post-hemorrhagic hydrocephalus as underlying diagnosis (OR 13.1; 95% CI 1.9-163) showed significant increased odds ratio for shunt independence during follow-up. Logistic regression analysis for multiple parameters showed age > 6 months (OR 29.3; 95% CI 4.1-606) together with outward bulged lamina terminalis (OR 4.6; 95% CI 1.2-19.6), smaller FOHR (continuous parameter; OR 2.83 × 10-5; 95% CI 4.7 × 10-9-0.045), and non-4th-ventricular-outlet obstruction (4thVOO; OR 0.31; 95% CI 0.09-1.02) as significant factors for ETV success.

CONCLUSION

ETV has become a relevant treatment for non-communicating hydrocephalus, with typical MR image characteristics. Analyzing radiological markers as predictors for success smaller ventricular width and outward displaced lamina terminalis was relevant in combination with age > 6 months. Since the analysis is based on single-center experience, a larger cohort of patients with a multi-center approach should further investigate the combined clinical and radiological criteria.

Cerebrospinal fluid diversion prior to posterior fossa tumor resection in adults: A systematic review

Background

Posterior fossa tumors (PFTs) comprise 15%-20% of adult brain tumors, with the reported frequency of hydrocephalus (HCP) ranging between 3.7% and 58%. Most HCP resolves after resection of PFTs, but studies report persistent or new-onset HCP occurring in between 2% and 7% of cases. Preoperative cerebrospinal fluid (CSF) diversion with a ventriculoperitoneal shunt (VPS), external ventricular drain (EVD), or endoscopic third ventriculostomy (ETV) has been shown to improve outcomes. Evidence regarding the efficacy of these techniques is limited.

Methods

A systematic literature search was performed in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Data points were extracted from individual patient cohort data. A failure rate was determined by the number of patients requiring further postoperative CSF diversion.

Results

In total, 8863 records were identified. Thirteen studies consisting of 17 patient cohorts met our inclusion criteria. Across all individual cohort studies, 2976 patients underwent surgical resection of a PFT in whom the frequency of hydrocephalus at presentation was 22.98% (1.92%-100%), and persistent hydrocephalus following preoperative CSF diversion was 13.63% (0%-18%). Of the 684 hydrocephalic patients, 83.63% underwent CSF diversion in the form of ETV, EVD, or VPS. Between years 1992 and 2020, 1986 and 2021, and 1981and 2013, the pre-resection ETV, EVD, and VPS failure rates were 14.66% (17/116), 16.26% (60/369), and 0% (0/87), respectively.

Conclusions

This systematic review highlights that VPS has a better failure rate profile in minimizing postoperative hydrocephalus in adult patients with PFTs.

Postoperative Cerebrospinal Fluid-Related Complications After Posterior Fossa and Posterolateral Skull Base Surgeries: Development of a Predictive Model and Clinical Risk Score

BACKGROUND

Postoperative pseudomeningocele (PMC) and cerebrospinal fluid (CSF) leak are common complications following posterior fossa and posterolateral skull base surgeries. We sought to 1) determine the rate of CSF-related complications and 2) develop a perioperative model and risk score to identify the highest risk patients for these events.

METHODS

We performed a retrospective cohort of 450 patients undergoing posterior fossa and posterolateral skull base procedures from 2016 to 2020. Logistic regressions were performed for predictor selection for 3 prespecified models: 1) a priori variables, 2) predictors selected by large effect sizes, and 3) predictors with P ≤ 0.100 on univariable analysis. A final model was created by elimination of nonsignificant predictors, and the integer-based postoperative CSF-related complications (POCC) clinical risk score was derived. Internal validation was done using 10-fold cross-validation and bootstrapping with uniform shrinkage.

RESULTS

A total of 115 patients (25.6%) developed PMC and/or CSF leakage. Age >55 years (odds ratio [OR], 0.560; 95% confidence interval [CI], 0.328-0.954), body mass index >30 kg/m2 (OR, 1.88; 95% CI, 1.14-3.10), and postoperative CSF diversion (OR, 2.85; 95% CI, 1.64-5.00) were associated with CSF leak and PMC. Model 2 was the most predictive (cross-validated area under the receiver operating characteristic curve, 0.690). The final risk score was devised using age, body mass index class, dural repair technique, use of bone substitute, and duration of postoperative CSF diversion. The POCC score performed well (cross-validated area under the receiver operating characteristic curve, 0.761) and was highly specific (96.1%).

CONCLUSIONS

We created the first generalizable and predictive risk score to identify patients at risk of CSF-related complications. The POCC score could improve surveillance, inform doctor-patient discussions regarding the risks of surgery, and assist in perioperative management.

A scoring system categorizing risk factors to evaluate the need for ventriculoperitoneal shunt in pediatric patients after brain tumor resection

Objectives

To develop a scoring system based on independent predictors of the need for ventriculoperitoneal (VP) shunt after brain tumor resection in pediatric patients.

Methods

A total of 416 pediatric patients (≤ 14 years old) with brain tumors who underwent surgery were randomly assigned to the training (n = 333) and validation cohorts (n = 83). Based on the implementation of VP shunt, the training cohort was divided into the VP shunt group (n = 35) and the non-VP shunt group (n = 298). Univariate and multivariate logistic analyses were performed. A scoring system was developed based on clinical characteristics and operative data, and scores and corresponding risks were calculated.

Results

Age < 3 (p = 0.010, odds ratio [OR] = 3.162), blood loss (BL) (p = 0.005, OR = 1.300), midline tumor location (p < 0.001, OR = 5.750), preoperative hydrocephalus (p = 0.001, OR = 7.044), and total resection (p = 0.025, OR = 0.284) were identified as independent predictors. The area under the curve (AUC) of the scoring system was higher than those of age < 3, BL, midline tumor location, preoperative hydrocephalus, and total resection (0.859 vs. 0.598, 0.717, 0.725, 0.705, and 0.555, respectively; p < 0.001). Furthermore, the scoring system showed good performance in the validation cohort (AUC = 0.971). The cutoff value for predictive scores was 5.5 points, which categorized patients into low risk (0-5 points) and high risk (6-14 points) groups.

Conclusions

Our scoring system, integrating age < 3, BL, midline tumor location, preoperative hydrocephalus, and total resection, provides a practical evaluation. Scores ranging from 6 to 14 points indicate high risk.

Incidence and Risk Factors for Necessitating Cerebrospinal Fluid Diversion Following Medulloblastoma Surgery in Children

BACKGROUND

There are insufficient data on pediatric patients with medulloblastoma who require cerebrospinal fluid (CSF) diversion following resection. Therefore, this study aimed to determine the incidence and the characteristics associated with it in this subset of patients.

METHODS

We conducted a single-center, retrospective, observational cohort study of patients aged 18 years or less who underwent medulloblastoma resection at our department between 2010 and 2021. The primary outcome was the incidence of CSF diversion surgery required after resection. Participant demographics, tumor biology, and interventions were analyzed using univariate- and multivariate-adjusted models.

RESULTS

Of the 183 patients admitted to our department, 131 (71.6%) participated in this study. The incidence of permanent CSF diversion was 26.0% (95% confidence interval [CI]: 18.7 to 34.3). Factors independently associated with requirement of permanent CSF diversion were medulloblastoma volume >46.4 cm³ (odds ratio [OR]: 2.919, 95% CI: 1.191 to 7.156) and CSF channel invasion (OR: 2.849, 95% CI: 1.142 to 7.102). The duration of manifestation may be a covariate of tumor volume with increased risk of requirement for permanent CSF diversion (OR: 1.006, 95% CI: 1.000 to 1.013), and tumor volume may be a predictor in patients who underwent subtotal resection (OR: 4.900, 95% CI: 0.992 to 24.208, P = 0.05). Finally, patients who required permanent CSF diversion were divided according to medulloblastoma molecular subgroups, and no significant differences were found.

CONCLUSION

We report major predictive factors for permanent CSF diversion surgery in patients with medulloblastoma. Our study suggests that the presence of postresection hydrocephalus is not high enough to warrant permanent, prophylactic CSF diversion in all patients.

Blood Loss in Operation Is Independently Predictive of Postoperative Ventriculoperitoneal Shunt in Pediatric Patients With Posterior Fossa Tumors

BACKGROUND

To identify the risk factors for postoperative hydrocephalus and the need for ventriculoperitoneal (VP) shunt after posterior fossa tumor (PFT) resection in pediatric patients and establish a predictive model.

METHODS

A total of 217 pediatric patients (≤14 years old) with PFTs who underwent tumor resection from November 2010 to December 2020 were divided into a VP shunt group (n = 29) and non-VP shunt group (n = 188). Univariate and multivariate logistic regression were performed. A predictive model was established based on the independent predictors. Receiver operating characteristic curves were generated to determine the cutoff values and areas under the curve (AUCs). The Delong test was performed to compare the AUCs.

RESULTS

Age less than three years (P = 0.015, odds ratio [OR] = 3.760), blood loss (BL) (P = 0.002, OR = 1.601), and locations at fourth ventricle (P < 0.001, OR = 7.697) were the independent predictors. The predictive model was as follows: total score = age (<3; yes = 2, no = 0) + BL + tumor locations (fourth ventricle; yes = 5, no = 0). The AUC of our model was higher than those of age less than three years, BL, locations at the fourth ventricle, and compound factors (age <3 + locations) (0.842 vs 0.609, 0.734, 0.732, and 0.788, respectively). The cutoff values of the model and BL were 7.5 points and 2.75 U, respectively.

CONCLUSIONS

BL, age less than three years, and tumors at the fourth ventricle were independent predictors. Model scores over 7.5 points predict a high risk.

Placement of EVD in pediatric posterior fossa tumors: safe and efficient or old-fashioned? The Vienna experience

PURPOSE

The perioperative treatment of hydrocephalus in pediatric posterior fossa tumors with an external ventricular drain (EVD) is the treatment of choice in our center. We analyzed our experience in using EVD concerning safety and effectivity.

METHODS

This is a single-center retrospective cohort study of 100 consecutive pediatric patients who underwent resection for a newly diagnosed tumor in the posterior fossa between 2011 and 2022.

RESULTS

Of the 100 patients with posterior fossa tumors, 80 patients (80%) had radiological signs of hydrocephalus at presentation, 49 patients (49%) of whom underwent placement of an EVD. In 40 patients, the EVD was inserted at a mean of 2.25 days prior to the tumor resection; 9 had the EVD inserted during tumor resection (frontal trajectory in 7 patients, occipital trajectory in 2 patients). Histology revealed pilocytic astrocytoma in 48 patients, medulloblastoma in 32, ependymoma in 11, and other histologic entities in 9 patients. Gross total/near-total resection was achieved in 46 (95.83%) of the 48 pilocytic astrocytomas, 30 (93.75%) of the 32 medulloblastomas, and 11 (100%) of the 11 ependymomas. The mean number of total days with the EVD in place was 8.61 ± 3.82 (range 2-16 days). The mean number of days with an EVD after tumor resection was 6.35 ± 3.8 (range 0-16 days). EVD-associated complications were seen in 6 patients (12.24%) including one infection. None of these resulted in a worse clinical course or any long-term sequelae. Permanent CSF diversion at 6 months after surgery was necessary in 13 patients (13%), including two VP shunt, two SD-shunt, six endoscopic third ventriculostomy (ETV), and three combined VP shunt and ETV procedures. Patients with a medulloblastoma or ependymoma had a higher rate of permanent CSF diversion needed than the group of pilocytic astrocytoma patients (27.9% versus 2.13%, p < 0.001). In patients with metastatic disease, 7 of 17 patients (41.18%) needed a permanent CSF diversion, compared to 6 of 83 patients (7.23%) in the group without metastasis (p = 0.001).

CONCLUSION

The treatment of hydrocephalus in pediatric posterior fossa tumors with an EVD as a temporary measure is safe and effective, provided that a multi-professional understanding for its handling is given and there is no need for a long transport of the children.

Perioperative external ventricular drainage vs. no-EVD strategy in pediatric posterior fossa tumors-pilot study results

INTRODUCTION

Pediatric brain tumors of the posterior fossa often present with occlusive hydrocephalus. Endoscopic third ventriculostomy (ETV) or ventriculoperitoneal shunting (VPS) has been established for definite hydrocephalus treatment. The aim of the study was to analyze the impact and safety of perioperative temporary external ventricular CSF drainage (EVD) placement on postoperative hydrocephalus outcome compared to a no-EVD strategy.

PATIENTS AND METHODS

In a prospective database, 36 posterior fossa tumor patients of 2-18 years were included with a follow-up of 1 year. Fifty-eight percent presented with preoperative hydrocephalus. Patients were assigned to non-hydrocephalus group: group I (n = 15) and to preoperative hydrocephalus, group IIa with EVD placement (n = 9), and group IIb without EVD (n = 12).

RESULTS

Median age of patients was 8.1 years (range 3.17 to 16.58 years). One-third of 21 hydrocephalus patients required ETV or VPS (n = 7). Occurrence of de novo hydrocephalus in group I after surgery was not observed in our cohort. Age and histology were no confounding factor for EVD placement between group IIa and IIb (p = 0.34). The use of EVD did not result in better control of hydrocephalus compared to no-EVD patients considering pre- and postoperative MRI ventricular indices (p = 0.4). Perioperative placement of an EVD resulted in a threefold risk for subsequent VPS or ETV (group IIa 55.5% vs group IIb 16.6%): relative risk for EVD patients compared to no-EVD patients with hydrocephalus was 3.3 (CI = 1.06-13.43, p = 0.09).

CONCLUSION

Perioperative EVD placement appears to harbor a threefold relative risk of requiring subsequent permanent CSF diversion in children above 2 years. EVD was not more effective to control ventricular enlargement compared to tumor removal alone. The no-EVD strategy was safe and did not result in postoperative complications. Thus, to evaluate potential adverse effects on hydrocephalus outcome by EVD placement, a prospective study is warranted to falsify the results.

Management of Posterior Fossa Tumors in Adults Based on the Predictors of Postoperative Hydrocephalus

Objective

This study aims to identify the predictors of postoperative hydrocephalus in patients with posterior fossa tumors (PFTs) and guide the management of perioperative hydrocephalus.

Methods

We performed a single-institution, retrospective analysis of patients who underwent resection of PFTs in our department over a 10-year period (2011–2021). A total of 682 adult patients met the inclusion criteria and were divided into either a prophylactic external ventricular drainage (EVD) group or a nonprophylactic-EVD group. We analyzed data for the nonprophylactic-EVD group by univariate and multivariate analyses to identify predictors of postoperative acute hydrocephalus. We also analyzed all cases by univariate and multivariate analyses to determine the predictors of postoperative ventriculoperitoneal (VP) shunt placement.

Results

Tumor infiltrating the midbrain aqueduct [P = 0.001; odds ratio (OR) = 9.8], postoperative hemorrhage (P &lt; 0.001; OR = 66.7), and subtotal resection (P = 0.006; OR = 9.3) were independent risk factors for postoperative EVD. Tumor infiltrating the ventricular system (P &lt; 0.001; OR = 58.5) and postoperative hemorrhage (P &lt; 0.001; OR = 28.1) were independent risk factors for postoperative VP shunt placement.

Conclusions

These findings may help promote more aggressive monitoring and earlier interventions for postoperative hydrocephalus in patients with PFTs.

Posterior Fossa Tumours in the First Year of Life: A Two-Centre Retrospective Study

Posterior fossa tumours (PFTs) in infants are very rare, and information on these tumours is scarce in the literature. This retrospective study reports their pathological characteristics and describes surgical aspects and treatment outcomes. A two-centre cohort of infants with PFTs treated from 2007 to 2018 was retrospectively reviewed. Patient characteristics, clinical, and treatment data were reviewed. Survival curves for progression-free survival (PFS) and overall survival (OS) were generated. Thirty-three infants were retrieved. There were 11 low grade and 22 high-grade tumours. The most common presenting symptom was intracranial hypertension. Fifteen children out of thirty-three progressed. Five-year PFS was significantly lower in children with high-grade tumours (38.3%) than those with low-grade tumours (69.3%), p = 0.030. High-grade pathology was the only predictor of progression (HR 3.7, 95% CI 1.1–13.31), p = 0.045. Fourteen children with high-grade tumours died, with a 5-year OS of 55.25%. PFTs in children below one year of age still represent a unique challenge. Infants with high-grade tumours display the worst outcomes and the lowest survival, indicating that more effective strategies are needed.

Risk Factors of Persistent Hydrocephalus in Children with Brain Tumor: A Retrospective Analysis

OBJECT

Hydrocephalus is one of the main complications of brain tumors in children, being present in about 50% of cases at the time of the tumor diagnosis and persisting up to 10-40% of cases after surgical resection. This is a single-institution retrospective study on the variables that may predict the need for treatment of persistent hydrocephalus in pediatric patients presenting with a brain tumor.

METHODS

Retrospective case note review of 43 newly diagnosed brain tumors in children referred between April 2012 and January 2018 to our regional pediatric neuro-oncology service was carried out. Diagnosis of hydrocephalus was carried out using both preoperative and postoperative MRI to determine Evans' index (EI) and the fronto-occipital horn ratio (FOHR) from each scan. Simple logistic regression was used to analyze categorical variables as appropriate. A p value <0.05 was considered significant.

RESULTS

Forty-three children were analyzed, 26 males and 17 females with a median age at diagnosis 10.4 years (IQR: 5.2-13.5). Hydrocephalus was present in 22/43 children (51%) preoperatively; in 8/22 children (36%) with hydrocephalus undergoing tumor resection, hydrocephalus persisted also in the postoperative period. An EI >0.34 (p = 0.028) and an FOHR >0.46 (p = 0.05) before surgery were associated with a higher prevalence of persistent hydrocephalus and therefore to the need for a cerebrospinal fluid drain device in the postoperative phase.

CONCLUSION

Preoperative identification of children at risk for developing persistent hydrocephalus would avoid delays in planning the permanent cerebrospinal fluid drain devices. This study finds that an EI >0.34 and an FOHR >0.46 at diagnosis could impact on the therapeutic management of children with hydrocephalus associated with brain tumors. Prospective and larger-scale studies are needed to standardize this approach.

The role of external ventricular drainage for the management of posterior cranial fossa tumours: a systematic review

Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after tumour removal in 70-90% and 96%, respectively. New onset hydrocephalus is reported in about 2.1% of adult and 10-40% of paediatric patients after posterior fossa surgery. There is no consensus concerning prophylactic external ventricular drainage (EVD) placement that is frequently used before posterior fossa lesion removal, as well in those cases without clear evidence of hydrocephalus. The aim of the study was to define the most correct management for patients who undergo posterior fossa tumour surgery, thus identifying cohorts of patients who are at risk of persistent hydrocephalus prior to surgery. A systematic review of literature has been performed, following PRISMA guidelines. Most of the studies reported CSF shunt only in the presence of hydrocephalus, whereas only a few authors suggested its prophylactic use in the absence of signs of ventricular dilatation. Predictive factors for postoperative hydrocephalus has been identified, including young age (< 3 years), severe symptomatic hydrocephalus at presentation, EVD placement before surgery, FOHR index > 0.46 and Evans index > 0.4, pseudomeningocele, CSF leak and infection. The use of pre-resection CSF shunt in case of signs and symptoms of hydrocephalus is mandatory, although it resolves in the majority of cases. As reported by several studies included in the present review, we suggest CSF shunt also in case of asymptomatic hydrocephalus, whereas it is not indicated without evidence of ventricular dilatation.