Treatment of hydrocephalus following posterior fossa tumor resection: a multicenter collaboration from the Hydrocephalus Clinical Research Network.

OBJECTIVE: Persistent hydrocephalus following posterior fossa brain tumor (PFBT) resection is a common cause of morbidity in pediatric brain tumor patients, for which the optimal treatment is debated. The purpose of this study was to compare treatment outcomes between VPS and ETV in patients with persistent hydrocephalus following surgical resection of a PFBT. METHODS: A post-hoc analysis was performed of the Hydrocephalus Clinical Research Network (HCRN) prospective observational study evaluating VPS and ETV for pediatric patients. Children who experienced hydrocephalus secondary to PFBT from 2008 to 2021 were included. Primary outcomes were VPS/ETV treatment failure and time-to-failure (TTF). RESULTS: Among 241 patients, the VPS (183) and ETV (58) groups were similar in age, extent of tumor resection, and preoperative ETV Success Score. There was no difference in overall treatment failure between VPS and ETV (33.9% vs 31.0%, p = 0.751). However, mean TTF was shorter for ETV than VPS (0.45 years vs 1.30 years, p = 0.001). While major complication profiles were similar, compared to VPS, ETV patients had relatively higher incidence of minor CSF leak (10.3% vs. 1.1%, p = 0.003) and pseudomeningocele (12.1% vs 3.3%, p = 0.02). No ETV failures were identified beyond 3 years, while shunt failures occurred beyond 5 years. Shunt infections occurred in 5.5% of the VPS cohort. CONCLUSIONS: ETV and VPS offer similar overall success rates for PFBT-related postoperative hydrocephalus. ETV failure occurs earlier, while susceptibility to VPS failure persists beyond 5 years. Tumor histology and grade may be considered when selecting the optimal means of CSF diversion.

Longitudinal CSF Iron Pathway Proteins in Posthemorrhagic Hydrocephalus: Associations with Ventricle Size and Neurodevelopmental Outcomes.

OBJECTIVE: Iron has been implicated in the pathogenesis of brain injury and hydrocephalus after preterm germinal matrix hemorrhage-intraventricular hemorrhage, however, it is unknown how external or endogenous intraventricular clearance of iron pathway proteins affect the outcome in this group. METHODS: This prospective multicenter cohort included patients with posthemorrhagic hydrocephalus (PHH) who underwent (1) temporary and permanent cerebrospinal fluid (CSF) diversion and (2) Bayley Scales of Infant Development-III testing around 2 years of age. CSF proteins in the iron handling pathway were analyzed longitudinally and compared to ventricle size and neurodevelopmental outcomes. RESULTS: Thirty-seven patients met inclusion criteria with a median estimated gestational age at birth of 25 weeks; 65% were boys. Ventricular CSF levels of hemoglobin, iron, total bilirubin, and ferritin decreased between temporary and permanent CSF diversion with no change in CSF levels of ceruloplasmin, transferrin, haptoglobin, and hepcidin. There was an increase in CSF hemopexin during this interval. Larger ventricle size at permanent CSF diversion was associated with elevated CSF ferritin (p = 0.015) and decreased CSF hemopexin (p = 0.007). CSF levels of proteins at temporary CSF diversion were not associated with outcome, however, higher CSF transferrin at permanent CSF diversion was associated with improved cognitive outcome (p = 0.015). Importantly, longitudinal change in CSF iron pathway proteins, ferritin (decrease), and transferrin (increase) were associated with improved cognitive (p = 0.04) and motor (p = 0.03) scores and improved cognitive (p = 0.04), language (p = 0.035), and motor (p = 0.008) scores, respectively. INTERPRETATION: Longitudinal changes in CSF transferrin (increase) and ferritin (decrease) are associated with improved neurodevelopmental outcomes in neonatal PHH, with implications for understanding the pathogenesis of poor outcomes in PHH. ANN NEUROL 2021;90:217-226.

Insights into the epidemiology of infant hydrocephalus.

INTRODUCTION: Infant hydrocephalus represents an important public health issue. Recent analysis of registry-based data has improved our understanding of the variable epidemiology of infant hydrocephalus around the world and the consequent burden of disease that this vulnerable population must carry throughout their lifetimes. The purpose of this article is to review the epidemiology of infant hydrocephalus, highlighting the ways in which analysis of prospectively collected registry data has contributed to our current knowledge and how similar methods may lead to new discovery. DISCUSSION: Congenital abnormalities and spina bifida-associated hydrocephalus, along with acquired postnatal hydrocephalus secondary to intraventricular hemorrhage of prematurity and infection, represent the most common etiologies of infant hydrocephalus, with their relative prevalence dependent on geographic region and socioeconomic status. Best current estimates suggest that the incidence of congenital and acquired infant hydrocephalus may be between 80 and 125 cases/100,000 births depending on world region. These incidence figures and their forecasts, together with improved survival associated with promptly diagnosed and treated hydrocephalus, suggest that the burden of hydrocephalus, as measured by prevalence, is primed to increase. Counterbalancing these statistics is evidence that perhaps, in some regions, improvements in neurosurgical and general perinatal care, as well as shifting indications for initial surgical intervention in these infants (and therefore in the very definition of hydrocephalus itself), the number of infants who require first time surgical treatment for hydrocephalus, may be decreasing. Further longitudinal data collection will undoubtedly assist in determining whether these trends are robust. CONCLUSION: When one takes a global perspective, complexities related to the underlying epidemiology of infant hydrocephalus become abundantly clear. The causes of infant hydrocephalus vary from one world region to another, largely related to the underlying income characteristics of the population. Likewise, increased birth rates in low-income areas of the world are likely to result in an increased incidence and prevalence of infant hydrocephalus in those regions, whereas sophisticated and resource-intensive advancements in perinatal care available in other regions may result in decreased epidemiological estimates of disease burden in others. Further analysis of high-quality registry-based data may help clarify these issues.

Long-term upper extremity performance in children with cerebral palsy following selective dorsal rhizotomy.

PURPOSE: In children with spastic cerebral palsy, selective dorsal rhizotomy (SDR) is conducted to improve lower limb spasticity. Improvements in upper extremity function have also been noted in early follow-up. The purpose of this study was to determine if upper extremity improvements are sustained in the long term. METHODS: A retrospective review of prospectively collected data on children who underwent SDR was conducted. Quality of Upper Extremities Skill Test (QUEST) scores for dissociated movement, grasp and total scores were compared using repeated measures ANOVA for individual patients at three time points: preoperatively, early post-operatively (≤ 2 years) and late post-operatively (9+ years). RESULTS: Out of 200+ patients having SDR, 32 had QUEST assessment at all three time points. Significant improvements in QUEST dissociated movement (F = 3.665, p = 0.045), grasp (F = 7.995, p = 0.001) and total scores (F = 9.471, p = 0.001) were found. Pairwise comparisons were significant from pre-operative to early post-operative times for all QUEST scores (p = 0.001, 0.003, 0.001), and this was maintained at late post-operative assessment for grasp and total scores (p = 0.02, p = 0.02). There was no significant change in scores between early and late post-operative assessment time points. CONCLUSION: Early improvements in upper extremity QUEST total scores are sustained in the long term following SDR.

Immediate replacement of bone flap after craniotomy for empyema in children.

PURPOSE: Optimal management of the bone flap after craniotomy for intracranial infection has not been well defined in the pediatric population. This study reviewed the outcomes of a single Canadian center where immediate replacement of the bone flap was standard practice. METHODS: This is a retrospective study of all patients who underwent craniotomies for evacuation of epidural or subdural empyema at a single center from 1982 to 2018. Patients were identified using the prospective surgical database maintained by the Division of Pediatric Neurosurgery at BC Children's Hospital. Primary outcome was treatment failure, defined as reoperation at the site of initial surgery for removal of an infected bone flap or repeat drainage of empyema under the replaced bone flap. Secondary outcome was any reoperation for recurrent infection at any site. RESULTS: Twenty-four patients met the inclusion criteria with a minimum of 3-month follow-up from the index intervention. Treatment failure occurred in four patients (17%), all of whom required repeat surgery for further drainage of pus underlying the bone flap. Mean time to repeat surgery was 13 days. Any reoperation for recurrent infection at any site occurred in three patients. Seven out of 24 patients required a second surgery to evacuate empyema (29.2%). Age, sex, epidural or subdural location, osteomyelitis, and bone flap wash were not associated with the primary outcome of treatment failure. CONCLUSION: Immediate replacement of the bone flap in the surgical management of pediatric subdural or epidural empyema is reasonable. Replacing the flap at the time of first surgery avoids the morbidity and costs of a subsequent reconstructive operation.

Hydrocephalus treatment in patients with craniosynostosis: an analysis from the Hydrocephalus Clinical Research Network prospective registry.

OBJECTIVE: Hydrocephalus may be seen in patients with multisuture craniosynostosis and, less commonly, single-suture craniosynostosis. The optimal treatment for hydrocephalus in this population is unknown. In this study, the authors aimed to evaluate the success rate of ventriculoperitoneal shunt (VPS) treatment and endoscopic third ventriculostomy (ETV) both with and without choroid plexus cauterization (CPC) in patients with craniosynostosis. METHODS: Utilizing the Hydrocephalus Clinical Research Network (HCRN) Core Data Project (Registry), the authors identified all patients who underwent treatment for hydrocephalus associated with craniosynostosis. Descriptive statistics, demographics, and surgical outcomes were evaluated. RESULTS: In total, 42 patients underwent treatment for hydrocephalus associated with craniosynostosis. The median gestational age at birth was 39.0 weeks (IQR 38.0, 40.0); 55% were female and 60% were White. The median age at first craniosynostosis surgery was 0.6 years (IQR 0.3, 1.7), and at the first permanent hydrocephalus surgery it was 1.2 years (IQR 0.5, 2.5). Thirty-three patients (79%) had multiple different sutures fused, and 9 had a single suture: 3 unicoronal (7%), 3 sagittal (7%), 2 lambdoidal (5%), and 1 unknown (2%). Syndromes were identified in 38 patients (90%), with Crouzon syndrome being the most common (n = 16, 42%). Ten patients (28%) received permanent hydrocephalus surgery before the first craniosynostosis surgery. Twenty-eight patients (67%) underwent VPS treatment, with the remaining 14 (33%) undergoing ETV with or without CPC (ETV ± CPC). Within 12 months after initial hydrocephalus intervention, 14 patients (34%) required revision (8 VPS and 6 ETV ± CPC). At the most recent follow-up, 21 patients (50%) required a revision. The revision rate decreased as age increased. The overall infection rate was 5% (VPS 7%, 0% ETV ± CPC). CONCLUSIONS: This is the largest prospective study reported on children with craniosynostosis and hydrocephalus. Hydrocephalus in children with craniosynostosis most commonly occurs in syndromic patients and multisuture fusion. It is treated at varying ages; however, most patients undergo surgery for craniosynostosis prior to hydrocephalus treatment. While VPS treatment is performed more frequently, VPS and ETV are both reasonable options, with decreasing revision rates with increasing age, for the treatment of hydrocephalus associated with craniosynostosis.

Tremor and Quality of Life in Patients With Advanced Essential Tremor Before and After Replacing Their Standard Deep Brain Stimulation With a Directional System.

OBJECTIVES: Patients with essential tremor treated with thalamic deep brain stimulation may experience increased tremor with the progression of their disease. Initially, this can be counteracted with increased stimulation. Eventually, this may cause unwanted side-effects as the circumferential stimulation from a standard ring contact spreads into adjacent regions. Directional leads may offer a solution to this clinical problem. We aimed to compare the ability of a standard and a directional system to reduce tremor without side-effects and to improve the quality of life for patients with advanced essential tremor. MATERIALS AND METHODS: Six advanced essential tremor patients with bilateral thalamic deep brain stimulation had their standard system replaced with a directional system. Tremor rating scale scores were prospectively evaluated before and after the replacement surgery. Secondary analyses of quality of life related to tremor, voice, and general health were assessed. RESULTS: There was a significantly greater reduction in tremor without side-effects (p = 0.017) when using the directional system. There were improvements in tremor (p = 0.031) and voice (p = 0.037) related quality of life but not in general health for patients using optimized stimulation settings with the directional system compared to the standard system. CONCLUSIONS: In this cohort of advanced essential tremor patients who no longer had ideal tremor reduction with a standard system, replacing their deep brain stimulation with a directional system significantly improved their tremor and quality of life. Up-front implantation of directional deep brain stimulation leads may provide better tremor control in those patients who progress at a later time point.

Evaluation of the Patient-Practitioner Consultation on Surgical Treatment Options for Patients With Craniosynostosis.

INTRODUCTION: Endoscope-assisted craniectomy and spring-assisted cranioplasty with post-surgical helmet molding are minimally invasive alternatives to the traditional craniosynostosis treatment of open cranial vault remodeling. Families are often faced with deciding between techniques. This study aimed to understand providers' practice patterns in consulting families about surgical options. METHODS: An online survey was developed and distributed to 31 providers. The response rate was 84% (26/31). RESULTS: Twenty-six (100%) respondents offer a minimally invasive surgical option for sagittal craniosynostosis, 21 (81%) for coronal, 20 (77%) for metopic, 18 (69%) for lambdoid, and 12 (46%) for multi-suture. Social issues considered in determining whether to offer a minimally invasive option include anticipated likelihood of compliance (23 = 88%), distance traveled for care (16 = 62%) and financial considerations (6 = 23%). Common tools to explain options include verbal discussion (25 = 96%), 3D reconstructed CT scans (17 = 65%), handouts (13 = 50%), 3D models (12 = 46%), hand drawings (11 = 42%) and slides (10 = 38%). Some respondents strongly (7 = 27%) or somewhat (3 = 12%) encourage a minimally invasive option over open repair. Others indicate they remain neutral (7 = 27%) or tailor their approach to meet perceived needs (8 = 31%). One (4%) somewhat encourages open repair. Despite this variation, all completely (17 = 65%), strongly (5 = 19%) or somewhat agree (4 = 15%) they use shared decision making in presenting surgical options. CONCLUSION: This survey highlights the range of practice patterns in presenting surgical options to families and reveals possible discrepancies in the extent providers believe they use shared decision making and the extent it is actually used.

Contrast-enhanced 3-dimensional Fluid-attenuated Inversion Recovery Sequences Have Greater Sensitivity for Detection of Leptomeningeal Metastases in Pediatric Brain Tumors Compared With Conventional Spoiled Gradient Echo Sequences.

Postcontrast 3-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequences have reduced vascular and flow-related artifacts and high sensitivity to low gadolinium concentrations. We compared the performance of postcontrast spoiled gradient echo images to 3D-FLAIR in the detection of leptomeningeal metastases in 47 pediatric patients with brain tumors. We found 10 cases with more leptomeningeal signal abnormalities on 3D-FLAIR. Overall there were significantly more lesions on 3D-FLAIR than spoiled gradient echo sequences. We believe the increased detection of leptomeningeal signal abnormality is due to increased sensitivity for low concentrations of gadolinium in regions of early blood brain barrier breakdown. Our study was limited by the lack of leptomeningeal metastases in cerebrospinal fluid sampling. We plan to conduct future studies which will determine whether the time-based concentration of gadolinium affects the performance and results. Future studies will also require more cases of pathology-proven leptomeningeal disease.

Canadian Assessment of Deep Brain Stimulation Access: The Canada Study.

BACKGROUND: The Canada Health Act requires reasonable access to all medically necessary therapies. No information is available to assess the current access to neuromodulation across Canada. This study quantifies the current rate of deep brain stimulation (DBS) for the entire country of Canada. Analyses were performed to determine whether there were differences in access based on provincial or territorial location, rural or non-rural region, or socioeconomic status. METHODS: All implanted DBS devices in Canada over a 2-year epoch (January 2015 to December 2016) were supplied by either Boston Scientific or Medtronic. Investigators received anonymized data from these companies, including patient age and home residence region. The 2016 Statistics Canada census data were used to determine the rate of DBS surgery and whether access was related to provincial location, rural versus non-rural region or socioeconomic status. RESULTS: A total of 722 patients were studied. The rate of DBS surgery for the entire country was ten per million population per year. Saskatchewan was significantly above (374%) the national average, whereas Quebec (40%) and Newfoundland & Labrador (32%) were significantly below the national average. No patients from the three territories received DBS. There were no significant differences in access from rural versus non-rural areas or in regions within provinces with different socioeconomic status. CONCLUSIONS: This is the first study to quantify all patients receiving DBS within an entire country. The current rate of DBS surgery within Canada is ten cases per million per year. Statistically significant regional differences were discovered and discussed.

Use of neuroimaging measurements of optic nerve sheath diameter to assess intracranial pressure in craniosynostosis.

PURPOSE: This study aims to evaluate accuracy of optic nerve sheath diameter (ONSD) measurements obtained by magnetic resonance imaging (MRI) in patients with craniosynostosis (CS) for detection of high intracranial pressure (ICP) and to correlate MRI-derived ONSD measurements with those obtained by computed tomography (CT) scans in CS patients. METHODS: A retrospective review was conducted on CS patients who had MRI- and age-matched controls with normal MRI. Diagnosis of intracranial hypertension was based on presence of papilledema, direct ICP monitoring, and/or lumbar puncture. The search also included patients with MRI and CT done within 30 days apart. ONSDs were measured 3 mm behind the globe on both modalities. RESULTS: The study identified 56 CS patients (mean age 3.8 ± 3.47 years) and 49 controls (mean age 3.7 ± 3.62 years). Mean ONSD in patients with high ICP was significantly higher than in patients without high ICP (P = 0.0001) and in controls (P < 0.0001). The optimal ONSD threshold for predicting raised ICP in patients >1 year old was 6 mm (71.4% sensitivity, 89.7% specificity). Nineteen patients with 38 single-eye MRI/CT pairs were identified. Substantial agreement between both modalities resulted (r = 0.959, 95% CI 0.923-0.978), and Bland and Altman Plot analysis showed that 95% of measurements fell within limits of agreement (1.96 SD; ± 0.6 mm). CONCLUSION: In CS patients, ONSD measured by MRI represent indirect non-invasive means of ICP assessment. Both MRI and CT measurements of ONSD gave comparable results, and the use of CT-derived ONSD measurements may give some idea about ICP in CS patients.

Variability in Management of First Cerebrospinal Fluid Shunt Infection: A Prospective Multi-Institutional Observational Cohort Study.

OBJECTIVES: To describe the variation in approaches to surgical and antibiotic treatment for first cerebrospinal fluid (CSF) shunt infection and adherence to Infectious Diseases Society of America (IDSA) guidelines. STUDY DESIGN: We conducted a prospective cohort study of children undergoing treatment for first CSF infection at 7 Hydrocephalus Clinical Research Network hospitals from April 2008 through December 2012. Univariate analyses were performed to describe the study population. RESULTS: A total of 151 children underwent treatment for first CSF shunt-related infection. Most children had undergone initial CSF shunt placement before the age of 6 months (n = 98, 65%). Median time to infection after shunt surgery was 28 days (IQR 15-52 days). Surgical management was most often shunt removal with interim external ventricular drain placement, followed by new shunt insertion (n = 122, 81%). Median time from first negative CSF culture to final surgical procedure was 14 days (IQR 10-21 days). Median duration of intravenous (IV) antibiotic use duration was 19 days (IQR 12-28 days). For 84 infections addressed by IDSA guidelines, 7 (8%) met guidelines and 61 (73%) had longer duration of IV antibiotic use than recommended. CONCLUSIONS: Surgical treatment for infection frequently adheres to IDSA guidelines of shunt removal with external ventricular drain placement followed by new shunt insertion. However, duration of IV antibiotic use in CSF shunt infection treatment was consistently longer than recommended by the 2004 IDSA guidelines.

Risk factors for first cerebrospinal fluid shunt infection: findings from a multi-center prospective cohort study.

OBJECTIVE: To quantify the extent to which cerebrospinal fluid (CSF) shunt revisions are associated with increased risk of CSF shunt infection, after adjusting for patient factors that may contribute to infection risk. STUDY DESIGN: We used the Hydrocephalus Clinical Research Network registry to assemble a large prospective 6-center cohort of 1036 children undergoing initial CSF shunt placement between April 2008 and January 2012. The primary outcome of interest was first CSF shunt infection. Data for initial CSF shunt placement and all subsequent CSF shunt revisions prior to first CSF shunt infection, where applicable, were obtained. The risk of first infection was estimated using a multivariable Cox proportional hazard model accounting for patient characteristics and CSF shunt revisions, and is reported using hazard ratios (HRs) with 95% CI. RESULTS: Of the 102 children who developed first infection within 12 months of placement, 33 (32%) followed one or more CSF shunt revisions. Baseline factors independently associated with risk of first infection included: gastrostomy tube (HR 2.0, 95% CI, 1.1, 3.3), age 6-12 months (HR 0.3, 95% CI, 0.1, 0.8), and prior neurosurgery (HR 0.4, 95% CI, 0.2, 0.9). After controlling for baseline factors, infection risk was most significantly associated with the need for revision (1 revision vs none, HR 3.9, 95% CI, 2.2, 6.5; ≥2 revisions, HR 13.0, 95% CI, 6.5, 24.9). CONCLUSIONS: This study quantifies the elevated risk of infection associated with shunt revisions observed in clinical practice. To reduce risk of infection risk, further work should optimize revision procedures.

Shunt infection prevention practices in Hydrocephalus Clinical Research Network-Quality: a new quality improvement network for hydrocephalus management.

OBJECTIVE: Knowledge-based tools used to standardize perioperative care, such as the shunt infection prevention protocol of the Hydrocephalus Clinical Research Network (HCRN), have demonstrated their ability to reduce surgeon-based and center-based variations in outcomes and improve patient care. The mere presence of high-quality evidence, however, does not necessarily translate into improved patient outcomes owing to the implementation gap. To advance understanding of how knowledge-based tools are being utilized in the routine clinical care of children with hydrocephalus, the HCRN-Quality (HCRNq) network was started in 2019. With a focus on CSF shunt infection, the authors present baseline data regarding CSF shunt infection rates and current shunt infection prevention practices in use at HCRNq sites. METHODS: Baseline shunt surgery practices, infection rate, and risk factor data were prospectively collected within HCRNq. No standard infection protocol was recommended, but site use of a protocol was implied if at least 3 of 6 common shunt infection prevention practices were used in > 80% of shunt surgical procedures. Univariable and multivariable analyses of shunt infection risk factors were performed. RESULTS: Thirty sites accrued data on 2437 procedures between November 2019 and June 2021. The unadjusted infection rate across all sites was 3.9% (range 0%-13%) and did not differ among shunt insertion, shunt revision, or shunt insertion after infection. Protocol use was implied for only 15/30 centers and 60% of shunt operations. On univariable analysis, iodine/DuraPrep (OR 0.57, 95% CI 0.37-0.88, p = 0.02) and the use of an antibiotic-impregnated catheter in any segment of the shunt (or both) decreased infection risk (OR 0.53, 95% CI 0.34-0.82, p = 0.01). Iodine-based prep solutions (OR 0.56, 95% 0.36-0.86, p = 0.02) and the use of antibiotic-impregnated catheters (OR 0.52, 95% CI 0.34-0.81, p = 0.01) retained significance in the multivariable model, but no relationship between protocol use and infection risk was demonstrated in this baseline analysis. CONCLUSIONS: The authors have demonstrated that children undergoing CSF shunt surgery at HCRNq sites share similar demographic characteristics with other large North American multicenter cohorts, with similar observed baseline infection rates and risk factors. Many centers have implemented standardized shunt infection prevention practices, but considerable practice variation remains. As such, there is an opportunity to decrease shunt infection rates in these centers through continued standardization of care.

A re-evaluation of the Endoscopic Third Ventriculostomy Success Score: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: The Hydrocephalus Clinical Research Network (HCRN) conducted a prospective study 1) to determine if a new, better-performing version of the Endoscopic Third Ventriculostomy Success Score (ETVSS) could be developed, 2) to explore the performance characteristics of the original ETVSS in a modern endoscopic third ventriculostomy (ETV) cohort, and 3) to determine if the addition of radiological variables to the ETVSS improved its predictive abilities. METHODS: From April 2008 to August 2019, children (corrected age ≤ 17.5 years) who underwent a first-time ETV for hydrocephalus were included in a prospective multicenter HCRN study. All children had at least 6 months of clinical follow-up and were followed since the index ETV in the HCRN Core Data Registry. Children who underwent choroid plexus cauterization were excluded. Outcome (ETV success) was defined as the lack of ETV failure within 6 months of the index procedure. Kaplan-Meier curves were constructed to evaluate time-dependent variables. Multivariable binary logistic models were built to evaluate predictors of ETV success. Model performance was evaluated with Hosmer-Lemeshow and Harrell's C statistics. RESULTS: Seven hundred sixty-one children underwent a first-time ETV. The rate of 6-month ETV success was 76%. The Hosmer-Lemeshow and Harrell's C statistics of the logistic model containing more granular age and etiology categorizations did not differ significantly from a model containing the ETVSS categories. In children ≥ 12 months of age with ETVSSs of 50 or 60, the original ETVSS underestimated success, but this analysis was limited by a small sample size. Fronto-occipital horn ratio (p = 0.37), maximum width of the third ventricle (p = 0.39), and downward concavity of the floor of the third ventricle (p = 0.63) did not predict ETV success. A possible association between the degree of prepontine adhesions on preoperative MRI and ETV success was detected, but this did not reach statistical significance. CONCLUSIONS: This modern, multicenter study of ETV success shows that the original ETVSS continues to demonstrate good predictive ability, which was not substantially improved with a new success score. There might be an association between preoperative prepontine adhesions and ETV success, and this needs to be evaluated in a future large prospective study.

Comparing ventriculoatrial and ventriculopleural shunts in pediatric hydrocephalus: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: When the peritoneal cavity cannot serve as the distal shunt terminus, nonperitoneal shunts, typically terminating in the atrium or pleural space, are used. The comparative effectiveness of these two terminus options has not been evaluated. The authors directly compared shunt survival and complication rates for ventriculoatrial (VA) and ventriculopleural (VPl) shunts in a pediatric cohort. METHODS: The Hydrocephalus Clinical Research Network Core Data Project was used to identify children ≤ 18 years of age who underwent either VA or VPl shunt insertion. The primary outcome was time to shunt failure. Secondary outcomes included distal site complications and frequency of shunt failure at 6, 12, and 24 months. RESULTS: The search criteria yielded 416 children from 14 centers with either a VA (n = 318) or VPl (n = 98) shunt, including those converted from ventriculoperitoneal shunts. Children with VA shunts had a lower median age at insertion (6.1 years vs 12.4 years, p < 0.001). Among those children with VA shunts, a hydrocephalus etiology of intraventricular hemorrhage (IVH) secondary to prematurity comprised a higher proportion (47.0% vs 31.2%) and myelomeningocele comprised a lower proportion (17.8% vs 27.3%) (p = 0.024) compared with those with VPl shunts. At 24 months, there was a higher cumulative number of revisions for VA shunts (48.6% vs 38.9%, p = 0.038). When stratified by patient age at shunt insertion, VA shunts in children < 6 years had the lowest shunt survival rate (p < 0.001, log-rank test). After controlling for age and etiology, multivariable analysis did not find that shunt type (VA vs VPl) was predictive of time to shunt failure. No differences were found in the cumulative frequency of complications (VA 6.0% vs VPl 9.2%, p = 0.257), but there was a higher rate of pneumothorax in the VPl cohort (3.1% vs 0%, p = 0.013). CONCLUSIONS: Shunt survival was similar between VA and VPl shunts, although VA shunts are used more often, particularly in younger patients. Children < 6 years with VA shunts appeared to have the shortest shunt survival, which may be a result of the VA group having more cases of IVH secondary to prematurity; however, when age and etiology were included in a multivariable model, shunt location (atrium vs pleural space) was not associated with time to failure. The baseline differences between children treated with a VA versus a VPl shunt likely explain current practice patterns.

Acquisition and Analysis of Excised Neocortex from Pediatric Patients with Focal Cortical Dysplasia Using Mesoscale Diffusion MRI.

Non-invasive classification of focal cortical dysplasia (FCD) subtypes remains challenging from a radiology perspective. Quantitative imaging biomarkers (QIBs) have the potential to distinguish subtypes that lack pathognomonic features and might help in defining the extent of abnormal connectivity associated with each FCD subtype. A key motivation of diagnostic imaging is to improve the localization of a "lesion" that can guide the surgical resection of affected tissue, which is thought to cause seizures. Conversely, surgical resections to eliminate or reduce seizures provided unique opportunities to develop magnetic resonance imaging (MRI)-based QIBs by affording long scan times to evaluate multiple contrast mechanisms at the mesoscale (0.5 mm isotropic voxel dimensions). Using ex vivo hybrid diffusion tensor imaging on a 9.4 T MRI scanner, the grey to white matter ratio of scalar indices was lower in the resected middle temporal gyrus (MTG) of two neuropathologically confirmed cases of FCD compared to non-diseased control postmortem fixed temporal lobes. In contrast, fractional anisotropy was increased within FCD and also adjacent white matter tracts. Connectivity (streamlines/mm3) in the MTG was higher in FCD, suggesting that an altered connectivity at the lesion locus can potentially provide a tangible QIB to distinguish and characterize FCD abnormalities. However, as illustrated here, a major challenge for a robust tractographical comparison lies in the considerable differences in the ex vivo processing of bioptic and postmortem samples. Mesoscale diffusion MRI has the potential to better define and characterize epileptic tissues obtained from surgical resection to advance our understanding of disease etiology and treatment.

Comparison of outcomes in the management of abdominal pseudocyst in children with shunted hydrocephalus: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: Abdominal pseudocyst (APC) can cause distal site failure in children with ventriculoperitoneal shunts and is specifically designated as an infection in Hydrocephalus Clinical Research Network (HCRN) protocols. Specific management and outcomes of children with APCs have not been reported in a multicenter study. In this study, the authors investigated the management and outcomes of APC in children with shunted hydrocephalus who were treated at centers in the HCRN. METHODS: The HCRN Registry was queried to identify children < 18 years old with shunts who were diagnosed with an APC (i.e., a loculated abdominal fluid collection containing the peritoneal catheter with abdominal distention and/or displacement of peritoneal contents). The primary outcome was shunt failure after APC treatment. The primary variable was reimplantation of the distal catheter after pseudocyst treatment back into the peritoneum versus implantation in a nonperitoneal site. Other risk factors for shunt failure after APC treatment and variability in APC management were investigated. RESULTS: Among 141 children from 14 centers who underwent first-time management of an APC over a 14-year period, the median time from previous shunt surgery to APC diagnosis was 3.8 months. Overall, 17.7% of children had a positive culture: APC cultures were positive in 14.2% and CSF cultures in 15.6%. Six other children underwent shunt revision without removal; all underwent reoperation within 1 month. There was no difference in shunt survival (log-rank test, p = 0.42) or number of subsequent revisions within 6, 12, or 24 months for shunts reimplanted in the abdomen versus those implanted in a nonperitoneal location. Nonperitoneal implantation was associated with more noninfectious revisions (42.3% vs 22.9%, p = 0.019), whereas infection was more common after reimplantation in the abdomen (25.7% vs 7.0%, p = 0.003). Univariable analysis demonstrated that younger age at APC diagnosis (8.3 vs 12.2 years, p = 0.006) and prior shunt procedure within 12 weeks of APC diagnosis (59.5% vs 40.5%, p = 0.012) were associated with shunt failure after APC treatment. Multivariable modeling confirmed that prior shunt surgery within 12 weeks of APC diagnosis was independently associated with failure (HR 1.79 [95% CI 1.04-3.07], p = 0.035). CONCLUSIONS: In the HCRN, APCs in the setting of CSF shunts are usually managed with externalization. Shunt surgery within 12 weeks of APC diagnosis was associated with risk of failure after APC treatment. Although no differences were found in overall shunt failure rate, noninfectious shunt revisions were more common in the nonperitoneal distal catheter sites, and infection was a more common reason for failure after reimplantation of the shunt in the abdomen.

A qualitative study of transitioning patients with hydrocephalus from pediatric to adult care: fear of uncertainty, communication gaps, independence, and loss of relationships.

OBJECTIVE: Hydrocephalus is one of the most common condition treated by pediatric neurosurgeons. Many neurosurgeons are unable to continue to care for patients after they become adults. Although significant gaps in care are believed to exist for youth transitioning from pediatric to adult care, very little is known about how patients and their caregivers feel about the process. This qualitative study sought to examine the perceptions of adolescents, young adults, and their caregivers regarding transitioning from pediatric to adult care at a single Canadian center. METHODS: The authors explored the perceptions of patients with treated hydrocephalus and their caregivers using semistructured interviews and qualitative research methodologies. A convenience sample was recruited, composed of adolescent patients and their caregivers at the neurosurgery clinic of BC Children's Hospital, and patients and caregivers recently transitioned to adult care from the clinic. Interviews were transcribed verbatim and coded, with common themes identified. RESULTS: Four overarching themes relating to the process of transitioning from pediatric to adult hydrocephalus care for patients and their caregivers were identified from the data: 1) achieving independence, 2) communication gaps, 3) loss of significant relationships and environment, and 4) fear of uncertainty. CONCLUSIONS: Overall, patients with hydrocephalus and their families are dissatisfied with the process of transitioning. This study identified common themes and concerns among this cohort that may form the basis of an improved transition model for youth with hydrocephalus as they become adults.