Predicting the presence of 4th ventricular outlet obstruction in Chiari I Malformation.

INTRODUCTION: A subset of children with Chiari 1 malformation (CM-1) have a 4th ventricle arachnoid veil-a thin membrane covering the outlet of the 4th ventricle. Studies suggest that failure to disrupt this veil during posterior fossa decompression can reduce the likelihood of syringomyelia resolution. However, there is no reliable method for predicting the presence of the veil without direct surgical exploration. This study aims to evaluate the association between pre-operative symptoms, radiographic measurements, and the arachnoid veil. METHODS: A retrospective review of an institutional database of children evaluated for CM-I was conducted. For patients treated with surgery, operative notes were reviewed to determine if an arachnoid veil was present. Logistic regression was used to test for relationship of clinical variables and radiographic measurements with the presence of an arachnoid veil. RESULTS: Out of 997 children with CM-1, 226 surgical patients were included in the analysis after excluding those with inadequate documentation. An arachnoid veil was found in 23 patients (10.2%). Larger syrinx, spinal canal, and thecal sac diameters were significantly associated with the presence of a veil, with odds ratios of 1.23 (95% CI 1.2-1.48; p = 0.03), 1.27 (95% CI 1.02-1.59; p = 0.03), and 1.35 (95% CI 1.03-1.77; p = 0.03), respectively. No significant associations were found with any signs or symptoms. CONCLUSIONS: Arachnoid veil was present in 10% of cases. Radiographic measurements indicating larger syrinx size were the only variables found to be significantly associated with an arachnoid veil. Exploration of the 4th ventricular outlet is recommended for CM-I decompression in the setting of expansile syringomyelia.

Endovascular balloon usage in endoscopic third ventriculostomy for hydrocephalus during a national shortage: case series and technical note.

Endoscopic third ventriculostomy (ETV) is a well-established surgical technique for treating hydrocephalus. Many providers have transitioned to utilizing the specialized Neuroballoon for the stoma dilation in ETV; however, these devices are intermittently unavailable during supply chain shortages. We present the experience of employing cardiac angioplasty and neurovascular balloons as substitutes for the Neuroballoon in 3 patients. The scepter balloon (Microvention), priced at $1800 compared to the standard $300 Neuroballoon (Integra), proved effective, but its pliability presented technical challenges. The substantial cost differential compared to a Neuroballoon ($300) raises economic considerations. The Cardiac TREK balloon (Abbott) was similarly effective, while also being easier to manage endoscopically and cheaper at $158. These experiences support the viability of non-neuroendoscopic specialized balloons as alternatives for ETV dilation of the floor of tuber cinereum.

Characteristics and outcomes of pediatric dural arteriovenous fistulas: a systematic review.

BACKGROUND: Dural arteriovenous fistulas (dAVF) are arteriovenous shunts in communication with the dural vasculature in the brain or spine. Apart from single-center series, risk factors and treatment outcomes for pediatric dAVFs are largely undescribed. METHODS: We performed a systematic literature review of pediatric (< 18 years at diagnosis) intracranial and spinal dAVF according to PRISMA guidelines. We queried PubMed, CINAHL, SCOPUS, and Embase databases without time/date restriction. Search strings included a variety of MeSH keywords relating to dural AV fistulas in combination with MeSH keywords related to pediatric cases (see Appendix). Manuscripts describing patients diagnosed with dural sinus malformations or pial AVF were excluded. RESULTS: We identified 61 studies describing 69 individual patients. Overall, dAVF were more common in males (55.1%) with a mean age of diagnosis (5.17 ± 4.42 years). Approximately 20.2% of patients presented with cardiovascular disease (CVD), and 31.9% were discovered incidentally on neuroimaging studies. Transverse-sigmoid junction was the most common location (17.3%). Ninety-three percent (64 patients) were treated, most commonly using endovascular embolization (68.1%) followed by surgery (8.7%) and radiosurgery (2.9%). Almost half (43.8%) of dAVFs were completely obliterated. Of the 64 procedures, there were 19 neurological complications (29.7%) of varying severity where 12.5% were considered transient (i.e., pseudomeningocele) and 17.2% permanent (i.e., mortality secondary to acute sinus thrombosis, etc.). CONCLUSION: There is a paucity of information on pediatric dAVFs. This systematic review summarizes the published cases of dAVFs in the pediatric population. While the rate of missing data is high, there is publication bias, and precise details regarding complications are difficult to ascertain, this review serves as a descriptive summary of pediatric dAVFs.

Evaluation of multidisciplinary high-risk pregnancy clinic for myelomeningocele.

INTRODUCTION: A cross-sectional study retrospectively evaluating the perceived usefulness of attending a multi-disciplinary, roundtable, educational prenatal clinic for mothers expecting children with myelomeningocele is presented. METHODS: Mothers who currently have children with SB completed a survey which evaluated their overall preparedness, spina bifida education, delivery plans, surgical expectations, and expectations in terms of quality of life and development. Open comments were also collected. Statistical analysis was performed to identify differences between those who attended prenatal counseling and those who did not. RESULTS: Approximately half of these mothers received some form of prenatal SB counseling. Mothers who attended prenatal counseling reported that they felt more informed and prepared throughout their pregnancy, during the delivery of their child and during their initial hospital stay than mothers who did not. They reported that the roundtable discussions were beneficial, and the education they received was useful in helping them form accurate expectations and feel more at ease. CONCLUSION: This suggests that prenatal counseling and the High-Risk Pregnancy Clinic (HRPC) provides perceived utility to families and mothers and that the HRPC is an effective method of providing prenatal counseling to mothers whose unborn children have been diagnosed with myelomeningocele.

Neurosurgical management of Myelomeningocele in premature infants: a case series.

INTRODUCTION: Myelomeningocele (MMC) is the most common neural tube defect, but rarely seen in premature infants. Most centers advocate for closure of MMC within 24 h of birth. However, this is not always possible in severely premature infants. Given the rarity of this patient population, we aimed to share our institutional experience and outcomes of severely premature infants with MMC. METHODS: We performed a retrospective, observational review of premature infants (≤ 32 weeks gestational age) identified through our multidisciplinary spina bifida clinic (1995-2021) and surgical logs. Descriptive statistics were compiled about this sample including timing of MMC closure and incidence of adverse events such as sepsis, CSF diversion, meningitis, and death. RESULTS: Eight patients were identified (50% male) with MMC who were born ≤ 32 weeks gestational age. Mean gestational age of the population was 27.3 weeks (SD 3.5). Median time to MMC closure was 1.5 days (IQR = 1-80.8). Five patients were taken for surgery within the recommended 48 h of birth; 2 patients underwent significantly delayed closure (107 and 139 days); and one patient's defect epithelized without surgical intervention. Six of eight patients required permanent cerebrospinal fluid (CSF) diversion (2 patients were treated with ventriculoperitoneal shunting (VPS), three were treated with endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) and 1 patient treated with ETV; mean of 3 years after birth, ranging from 1 day to 16 years). Two patients required more than one permanent CSF diversion procedure. Two patients developed sepsis (defined as meeting at least 2/4 SIRS criteria). In both cases of sepsis, patients developed signs and symptoms more than 72 h after birth. Notably, both instances of sepsis occurred unrelated to operative intervention as they occurred before permanent MMC closure. Two patients had intraventricular hemorrhage (both grade III). No patients developed meningitis (defined as positive CSF cultures) prior to MMC closure. Median follow up duration was 9.7 years. During this time epoch, 3 patients died: Two before 2 years of age of causes unrelated to surgical intervention. One of the two patients with grade III IVH died within 24 h of MMC closure. CONCLUSIONS: In our institutional experience with premature infants with MMC, some patients underwent delayed MMC closure. The overall rate of meningitis, sepsis, and mortality for preterm children with MMC was similar to MMC patients born at term.

Pediatric non-galenic pial arteriovenous fistula's characteristics and outcomes: a systematic review.

INTRODUCTION: Pediatric non-galenic pial arteriovenous fistulas (pAVFs) are rare vascular malformations that are characterized by a pial arterial-venous connection without an intervening capillary bed. Outcomes and treatment strategies for pAVFs are highly individualized, owing to the rarity of the disease and lack of large-scale data guiding optimal treatment approaches. METHODS: We performed a systematic review of pediatric patients (< 18 years at diagnosis) diagnosed with a pAVF by digital subtraction angiogram (DSA). The demographics, treatment modalities, and outcomes were documented for each patient and clinical outcome data was collected. Descriptive information stratified by outcome scores were classified as follows: 1 = excellent (no deficit and full premorbid activity), 2 = good (mild deficit and full premorbid activity), 3 = fair (moderate deficit and impaired activity), 4 = poor (severe deficit and dependent on others), 5 = death. RESULTS: A total of 87 studies involving 231 patients were identified. Median age at diagnosis was 3 years (neonates to 18 years). There was slight male preponderance (55.4%), and 150 subjects (81.1%*) experienced excellent outcomes after treatment. Of the 189 patients treated using endovascular approaches, 80.3% experienced excellent outcomes and of the 15 patients surgically treated subjects 75% had an excellent outcome. The highest rate of excellent outcomes was achieved in patients treated with Onyx (95.2%) and other forms of EvOH (100%). High output heart failure and comorbid vascular lesions tended to result in worse outcomes, with only 54.2% and 68% of subjects experiencing an excellent outcome, respectively. *Outcomes were reported in only 185 patients. CONCLUSION: pAVFs are rare lesions, necessitating aggregation of patient data to inform natural history and optimal treatment strategies. This review summarizes the current literature on pAVF in children, where children presenting with heart failure as a result of high flow through the lesion were less likely to experience an excellent outcome. Prospective, large-scale studies would further characterize pediatric pAVFs and enable quantitative analysis of outcomes to inform best treatment practices.

Expedited epilepsy surgery prior to drug resistance in children: a frontier worth crossing?

Epilepsy surgery is an established safe and effective treatment for selected candidates with drug-resistant epilepsy. In this opinion piece, we outline the clinical and experimental evidence for selectively considering epilepsy surgery prior to drug resistance. Our rationale for expedited surgery is based on the observations that (i) a high proportion of patients with lesional epilepsies (e.g. focal cortical dysplasia, epilepsy-associated tumours) will progress to drug resistance; (ii) surgical treatment of these lesions, especially in non-eloquent areas of brain, is safe; and (iii) earlier surgery may be associated with better seizure outcomes. Potential benefits beyond seizure reduction or elimination include less exposure to antiseizure medications, which may lead to improved developmental trajectories in children and optimize long-term neurocognitive outcomes and quality of life. Further, there exists emerging experimental evidence that brain network dysfunction exists at the onset of epilepsy, where continuing dysfunctional activity could exacerbate network perturbations. This in turn could lead to expanded seizure foci and contribution to the comorbidities associated with epilepsy. Taken together, we rationalize that epilepsy surgery, in carefully selected cases, may be considered prior to drug resistance. Last, we outline the path forward, including the challenges associated with developing the evidence base and implementing this paradigm into clinical care.

What has changed in pediatric neurosurgical care in spina bifida? A 30-year UAB/Children's of Alabama observational overview.

Spina bifida (SB) remains the most serious and most common congenital anomaly of the human nervous system that is compatible with life. The open myelomeningocele on the back is perhaps the most obvious initial problem, but the collective impact of dysraphism upon the entirety of the nervous system and innervated organs is an equal or greater longitudinal threat. As such, patients with myelomeningocele (MMC) are best managed in a multi-disciplinary clinic that brings together experienced medical, nursing, and therapy teams that provide high standards of care while studying outcomes and sharing insights and experiences. Since its inception 30 years ago, the spina bifida program at UAB/Children's of Alabama has remained dedicated to providing exemplary multi-disciplinary care for affected children and their families. During this time, there has been great change in the care landscape, but many of the neurosurgical principles and primary issues have remained the same. In utero myelomeningocele closure (IUMC) has revolutionized initial care and has favorable impact on several important co-morbidities of SB including hydrocephalus, the Chiari II malformation, and the functional level of the neurologic deficit. Hydrocephalus however is not solved by IUMC, and hydrocephalus management remains at the center of neurosurgical care in SB. Ventricular shunts were long the cornerstone of treatment for hydrocephalus, but we came to assess and incorporate endoscopic third ventriculostomy with choroid plexus coagulation (ETV-CPC). Educated and nurtured by an experienced senior mentor, we dedicated ourselves to fundamental concepts but persistently evaluated our care outcomes and evolved our protocols and paradigms for improvement. Active conversations amidst networks of treasured colleagues were central to this development and growth. While hydrocephalus support and treatment of tethered spinal cord remained our principal neurosurgical charges, we evolved to embrace a holistic perspective and approach that is reflected and captured in the Lifetime Care Plan. Our team engaged actively in important workshops and guideline initiatives and was central to the development and support of the National Spina Bifida Patient Registry. We started and developed an adult SB clinic to support our patients who aged out of pediatric care. Lessons there taught us the importance of a model of transition that emphasized personal responsibility and awareness of health and the crucial role of dedicated support over time. Support for sleep, bowel health, and personal intimate cares are important contributors to overall health and care. This paper details our growth, learning, and evolution of care provision over the past 30 years.

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.

Quantifying and reporting outcome measures in pediatric epilepsy surgery: A systematic review.

Several instruments and outcomes measures have been reported in pediatric patients undergoing epilepsy surgery. The objective of this systematic review is to summarize, evaluate, and quantify outcome metrics for the surgical treatment of pediatric epilepsy that address seizure frequency, neuropsychological, and health-related quality of life (HRQL). We performed a systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify publications between 2010 and June 2021 from PubMed, Embase, and the Cochrane Database of Systematic Reviews that report clinical outcomes in pediatric epilepsy surgery. Eighty-one articles were included for review. Overall, rates of postoperative seizure frequency were the most common metric reported (n = 78 studies, 96%). Among the seizure frequency metrics, the Engel Epilepsy Surgery Outcome Scale (n = 48 studies, 59%) was most commonly reported. Neuropsychological outcomes, performed in 32 studies (40%) were assessed using 36 different named metrics. HRQL outcomes were performed in 16 studies (20%) using 13 different metrics. Forty-six studies (57%) reported postoperative changes in antiepileptic drug (AED) regimen, and time-to-event analysis was performed in 15 (19%) studies. Only 13 outcomes metrics (1/5 seizure frequency, 6/13 HRQL, 6/36 neuropsychological) have been validated for use in pediatric patients with epilepsy and only 13 have been assessed through reliability studies (4/5 seizure frequency, 6/13 HRQL, and 3/36 neuropsychological). Of the 81 included studies, 17 (21%) used at least one validated metric. Outcome variable metrics in pediatric epilepsy surgery are highly variable. Although nearly all studies report seizure frequency, there is considerable variation in reporting. HRQL and neuropsychological outcomes are less frequently and much more heterogeneously reported. Reliable and validated outcomes metrics should be used to increase standardization and accuracy of reporting outcomes in pediatric patients undergoing epilepsy surgery.

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.

Treatment of pediatric high-grade central nervous system tumors with high-dose methotrexate in combination with multiagent chemotherapy: A single-institution experience.

BACKGROUND: Effective treatment for pediatric embryonal brain tumors includes dose-intensive multiagent chemotherapy (DIMAC) followed by high-dose chemotherapy with stem cell rescue (HDCSCR). Use of repeated cycles of DIMAC including high-dose methotrexate (HDMTX) without HDCSCR has not been described. PROCEDURE: We retrospectively reviewed the responses/toxicities in 13 patients (aged 2-155 months, median 22 months) with central nervous system (CNS) tumors (atypical teratoid rhabdoid tumors, CNS embryonal tumors not otherwise specified, pineoblastoma, embryonal tumor with multilayered rosettes, and CNS sarcoma) treated over a 12-year period with repeated cycles of HDMTX followed by etoposide, cisplatin, cyclophosphamide, and vincristine. RESULTS: Six patients (46.2%) had disseminated disease at presentation and five (38.5%) had gross total resection. A total of 64 courses of therapy were administered with a median of five courses per patient.  Eight patients (61.5%) received radiation therapy (one at relapse). By completion of therapy, 11 patients (84.6%) achieved a response (six complete, five partial).  Six of the 13 patients (46.2%) remain alive with a median follow-up of 48 months (6-146).  Acute toxicities included fever/neutropenia (70.3%), bacteremia (15.6%), and grade 3 mucositis (18.8%).  Long-term complications included learning disability, seizure disorder, and brain necrosis, without treatment-related deaths. CONCLUSIONS: DIMAC with HDMTX without HDCSCR may be an effective treatment option for selected patients with embryonal or high-grade CNS tumors.

Incidence of delayed intracranial hypertension in children with isolated sagittal synostosis following open calvarial vault reconstruction.

PURPOSE: Delayed intracranial hypertension (DIH) occurs most frequently in children with syndromic or multi-suture synostosis after surgical correction. The rarity of DIH in children with isolated non-syndromic sagittal synostosis (ISS) warrants follow-up evaluation by large craniofacial centers until skeletal maturity. This study reports the incidence of DIH in children following open repair for ISS by our center's craniofacial team. METHODS: A single-center retrospective study of patients who underwent open calvarial vault remodeling (CVR) for ISS at our institution between November 2000 and November 2012 was performed. Syndromic and multi-suture synostosis patients were excluded. Demographic and follow-up data were extracted from the medical record for analysis until July 2017. RESULTS: One hundred five patients with ISS were identified who had undergone CVR in the aforementioned timeframe. Average age at initial surgery was 11.7 ± 15.32 months. Mean follow-up in our craniofacial clinic was 4.94 ± 3.53 years, with 69 patients (65.7%) having follow-up in craniofacial clinic ≥ 3 years and 74 (70.5%) having follow-up ≥ 3 years in any clinic at our institution. Four patients (3.8%) had intracranial pressure (ICP) monitors placed for symptoms concerning for DIH, one of which (0.95%) had confirmed DIH and underwent a second surgical procedure at 7.4 years of age. The patient presented late initially, having his first operation at 1.56 years of age. CONCLUSION: One patient out of 105 (0.95%) developed DIH, confirmed by ICP monitoring, and required reoperation. The occurrence of DIH, albeit rare, remains an important topic to include in parental discussions and mandates long-term follow-up in this population.

Relative contribution of individual versus combined functional imaging studies in predicting seizure freedom in pediatric epilepsy surgery: an area under the curve analysis.

OBJECTIVE: The goal of this study was to evaluate the predictive value and relative contribution of noninvasive presurgical functional imaging modalities based on the authors' institutional experience in pursuing seizure-free surgical outcomes in children with medically refractory epilepsy. METHODS: This was a retrospective, single-institution, observational cohort study of pediatric patients who underwent evaluation and surgical treatment for medically refractory partial epilepsy between December 2003 and June 2016. During this interval, 108 children with medically refractory partial epilepsy underwent evaluation for localization and resective epilepsy surgery. Different noninvasive functional imaging modalities, including ictal SPECT, FDG-PET, and magnetoencephalography-magnetic source imaging, were utilized to augment a standardized paradigm (electroencephalography/semiology, MRI, and neuropsychology findings) for localization. Outcomes were evaluated at a minimum of 2 years (mean 7.5 years) utilizing area under the receiver operating characteristic curve analysis. Localizing modalities and other clinical covariates were examined in relation to long-term surgical outcomes. RESULTS: There was variation in the contribution of each test, and no single presurgical workup modality could singularly and reliably predict a seizure-free outcome. However, concordance of presurgical modalities yielded a high predictive value. No difference in long-term outcomes between inconclusive (normal or diffusely abnormal) and abnormal focal MRI results were found. Long-term survival analyses revealed a statistically significant association between seizure freedom and patients with focal ictal EEG, early surgical intervention, and no history of generalized convulsions. CONCLUSIONS: Comprehensive preoperative evaluation utilizing multiple noninvasive functional imaging modalities is not redundant and can improve pediatric epilepsy surgical outcomes.

Trans-falcine and contralateral sub-frontal electrode placement in pediatric epilepsy surgery: technical note.

INTRODUCTION: Phase II monitoring with intracranial electroencephalography (ICEEG) occasionally requires bilateral placement of subdural (SD) strips, grids, and/or depth electrodes. While phase I monitoring often demonstrates a preponderance of unilateral findings, individual studies (video EEG, single photon emission computed tomography [SPECT], and positron emission tomography [PET]) can suggest or fail to exclude a contralateral epileptogenic onset zone. This study describes previously unreported techniques of trans-falcine and sub-frontal insertion of contralateral SD grids and depth electrodes for phase II monitoring in pediatric epilepsy surgery patients when concern about bilateral abnormalities has been elicited during phase I monitoring. METHODS: Pediatric patients with medically refractory epilepsy undergoing stage I surgery for phase II monitoring involving sub-frontal and/or trans-falcine insertion of SD grids and/or depth electrodes at the senior author's institution were retrospectively reviewed. Intra-operative technical details of sub-frontal and trans-falcine approaches were studied, while intra-operative complications or events were noted. Operative techniques included gentle subfrontal retraction and elevation of the olfactory tracts (while preserving the relationship between the olfactory bulb and cribriform plate) to insert SD grids across the midline for coverage of the contralateral orbito-frontal regions. Trans-falcine approaches involved accessing the inter-hemispheric space, bipolar cauterization of the anterior falx cerebri below the superior sagittal sinus, and sharp dissection using a blunt elevator and small blade scalpel. The falcine window allowed contralateral SD strip, grid, and depth electrodes to be inserted for coverage of the contralateral frontal regions. RESULTS: The study cohort included seven patients undergoing sub-frontal and/or trans-falcine insertion of contralateral SD strip, grid, and/or depth electrodes from February 2012 through June 2015. Five patients (71%) experienced no intra-operative events related to contralateral ICEEG electrode insertion. Intra-operative events of frontal territory venous engorgement (1/7, 14%) due to sacrifice of anterior bridging veins draining into the SSS and avulsion of a contralateral bridging vein (1/7, 14%), probably due to prior anterior corpus callosotomy, each occurred in one patient. There were no intra-operative or peri-operative complications in any of the patients studied. Two patients required additional surgery for supplemental SD strip and/or depth electrodes via burr hole craniectomy to enhance phase II monitoring. All patients proceeded to stage II surgery for resection of ipsilateral epileptogenic onset zones without adverse events. CONCLUSIONS: Trans-falcine and sub-frontal insertion of contralateral SD strip, grid, and depth electrodes are previously unreported techniques for achieving bilateral frontal coverage in phase II monitoring in pediatric epilepsy surgery. This technique obviates the need for contralateral craniotomy and parenchymal exposure with limited, remediable risks. Larger case series using the method described herein are now necessary.

Endoscopic third ventriculostomy: A historical review.

BACKGROUND: Endoscopic third ventriculostomy (ETV) has become one of the most common neuroendoscopic procedures. METHODS: In this article, we will review the major milestones in the history of ETV development from its early use by Walter Dandy to the techniques currently employed with advanced technology. CONCLUSIONS: ETV has become an important technique in the armamentarium of the neurosurgeon. From a meager beginning with few applications, our knowledge of long-term outcomes has evolved. ETV has a rich history and more recently, has had a renewed interest in its use. Our current understanding of its indications is growing and is based on a century of development through trial and error.

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.

Rate of shunt revision as a function of age in patients with shunted hydrocephalus due to myelomeningocele.

OBJECTIVE It is generally accepted that cerebrospinal fluid shunts fail most frequently in the first years of life. The purpose of this study was to describe the risk of shunt failure for a given patient age in a well-defined cohort with shunted hydrocephalus due to myelomeningocele (MMC). METHODS The authors analyzed data from their institutional spina bifida research database including all patients with MMC and shunted hydrocephalus. For the entire population, the number of shunt revisions in each year of life was determined. Then the number of patients at risk for shunt revision during each year of life was calculated, thus enabling them to calculate the rate of shunt revision per patient in each year of life. In this way, the timing of all shunt revision operations for the entire clinic population and the likelihood of having a shunt revision during each year of life were calculated. RESULTS A total of 655 patients were enrolled in the spina bifida research database, 519 of whom had a diagnosis of MMC and whose mean age was 17.48 ± 11.7 years (median 16 years, range 0-63 years). Four hundred seventeen patients had had a CSF shunt for the treatment of hydrocephalus and thus are included in this analysis. There were 94 shunt revisions in the 1st year of life, which represents a rate of 0.23 revisions per patient in that year. The rate of shunt revision per patient-year initially decreased as age increased, except for an increase in revision frequency in the early teen years. Shunt revisions continued to occur as late as 43 years of age. CONCLUSIONS These data substantiate the idea that shunt revision surgeries in patients with MMC are most common in the 1st year of life and decrease thereafter, except for an increase in the early teen years. A persistent risk of shunt failure was observed well into adult life. These findings underscore the importance of routine follow-up of all MMC patients with shunted hydrocephalus and will aid in counseling patients and families.

A comprehensive review of the sub-axial ligaments of the vertebral column: part I anatomy and function.

BACKGROUND: As important as the vertebral ligaments are in maintaining the integrity of the spinal column and protecting the contents of the spinal canal, a single detailed review of their anatomy and function is missing in the literature. METHODS: A literature search using online search engines was conducted. RESULTS: Single comprehensive reviews of the spinal ligaments are not found in the extant medical literature. CONCLUSIONS: This review will be useful to those who treat patients with pathology of the spine or who interpret imaging or investigate the anatomy of the ligaments of the vertebral column.

A comprehensive review of the sub-axial ligaments of the vertebral column: part II histology and embryology.

BACKGROUND: As important as the vertebral ligaments are in maintaining the integrity of the spinal column and protecting the contents of the spinal canal, a single detailed review of their histology and embryology is missing in the literature. METHODS: A literature search using online search engines was conducted. RESULTS: Single comprehensive reviews of the histology and embryology of the spinal ligaments are not found in the extant medical literature. CONCLUSIONS: This review will be useful to those who study or treat patients with pathology of the spine.