Journal of Neurosurgery: Pediatrics
Volume 27: Issue 3 (Mar 2021): Pages 243-373

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Author: Virtual Meeting | January 29, 2021
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Authors: Jack Lam, Patricia Tomaszewski, Guillaume Gilbert, Jeremy T. Moreau, Marie-Christine Guiot, Steffen Albrecht, Jean-Pierre Farmer, Jeffrey Atkinson, Christine Saint-Martin, Pia Wintermark, Boris Bernhardt, Sylvain Baillet, and Roy W. R. Dudley

In Brief

Researchers tested whether a noninvasive, non–contrast-based cerebral perfusion MRI technique, called arterial spin labeling (ASL), could detect the epileptogenic zone (EZ) in children with focal epilepsy who did not have obvious, well-defined structural brain lesions on MRI. Focal ASL abnormalities were found in over two-thirds of such cases and were concordant with the surgically proven EZ in 91% of children who underwent surgery. Due to the convenient and noninvasive nature of ASL, it may be reasonable to include this sequence in all routine MRIs done for focal epilepsy in children.

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Authors: Torin Karsonovich, Allyson Alexander, Sarah Graber, and Brent R. O’Neill

In Brief

The authors sought to compare the accuracy of boltless electrode placement with that of standard placement. Placing stereotactic EEG (SEEG) electrodes without anchor bolts is technically feasible. The accuracy of boltless electrodes was similar to that of electrodes placed with standard techniques. This technique allows electrodes to be placed in areas not amenable to standard techniques that utilize an anchor bolt, such as in very thin bone or the back of the head. This is the first description, to the authors’ knowledge, of such a technique being used in SEEG.

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Authors: Daiana R. Pur, Roy Eagleson, Marcus Lo, Michael T. Jurkiewicz, Andrea Andrade, and Sandrine de Ribaupierre

In Brief

The objective of this study was to use resting-state functional MRI to preoperatively map language networks in children with epilepsy. Language networks were identified at the individual level, and more than half of the cases in the study presented with atypical language lateralization, highlighting the need for brain mapping. Preoperatively identifying language networks in pediatric cases is challenging. However, it can help optimize electrode placement.

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Authors: Mandeep S. Tamber, John R. W. Kestle, Ron W. Reeder, Richard Holubkov, Jessica Alvey, Samuel R. Browd, James M. Drake, Abhaya V. Kulkarni, David D. Limbrick Jr., Patrick J. McDonald, Curtis J. Rozzelle, Tamara D. Simon, Robert Naftel, Chevis N. Shannon, John C. Wellons III, William E. Whitehead, Jay Riva-Cambrin, and for the Hydrocephalus Clinical Research Network

In Brief

The authors examined trends in the surgical treatment of pediatric hydrocephalus over an 8-year period and found that important changes in the treatment of this condition have occurred over a very short time frame. This work represents the first study using high-quality registry data to examine changes in the surgical care of pediatric hydrocephalus in North America.

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Authors: Jason S. Hauptman, John Kestle, Jay Riva-Cambrin, Abhaya V. Kulkarni, Samuel R. Browd, Curtis J. Rozzelle, William E. Whitehead, Robert P. Naftel, Jonathan Pindrik, David D. Limbrick Jr., James Drake, John C. Wellons III, Mandeep S. Tamber, Chevis N. Shannon, Tamara D. Simon, Ian F. Pollack, Patrick J. McDonald, Mark D. Krieger, Jason Chu, Todd C. Hankinson, Eric M. Jackson, Jessica S. Alvey, Ron W. Reeder, Richard Holubkov, and for the Hydrocephalus Clinical Research Network

In Brief

The objective of the study was to characterize and understand risk factors of rapid shunt failure in pediatric hydrocephalus. Age at shunt insertion and etiology of hydrocephalus are key risk factors of fast and ultrafast shunt failure. Fast shunt failure is an unfortunately common event in pediatric hydrocephalus. This study has been an important step in defining the phenomenon and trying to understand risk factors for children who experience fast shunt failure.

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Authors: Brandon G. Rocque, Raymond P. Waldrop, Isaac Shamblin, Anastasia A. Arynchyna, Betsy Hopson, Tammie Kerr, James M. Johnston, Curtis J. Rozzelle, and Jeffrey P. Blount

In Brief

In this study, the authors defined a new variable, shunt failure cluster, to perform the first analysis of multiple and frequent shunt failures. They found that 6% of children with ventriculoperitoneal shunts have a cluster of shunt failures, and that these patients account for 30% of all shunt revisions. Risk factors for shunt failure cluster include prematurity and history of shunt infection.

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Authors: Nathan A. Shlobin, Melissa A. LoPresti, Rebecca Y. Du, and Sandi Lam

In Brief

The authors reviewed the literature to evaluate folate fortification and supplementation policies and their impact on reducing folate-sensitive neural tube defects (NTDs). Mandatory fortification was more effective than voluntary supplementation. Policies incorporating fortification and supplementation may optimally reduce folate-sensitive NTDs. Reductions in NTDs are cost-effective over time. A multimodal approach incorporating mandatory fortification, appropriate supplementation, and improved infrastructure and access to prenatal care to lead to decreased incidences of NTDs worldwide is optimal. This approach should be context-specific and culturally appropriate, with emphasis on education and consideration for local access to healthcare and social determinants of health.

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Authors: Gloria Moreno-Madueño, Mónica Rivero-Garvía, Jorge Tirado-Caballero, and Javier Márquez-Rivas
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Authors: Mihir Gupta, Tiffany M. Chan, David R. Santiago-Dieppa, Anudeep Yekula, Carlos E. Sanchez, Jennifer D. Elster, John R. Crawford, Michael L. Levy, and David D. Gonda
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Authors: Elsa V. Arocho-Quinones, Sean M. Lew, and Andrew B. Foy

In Brief

The authors evaluated their series of vacuum-assisted elevation of skull fractures in pediatric patients and the variables affecting procedural outcomes. This study will add to the growing literature on the use of nonsurgical management of depressed skull fractures in pediatric patients and help practitioners with decision-making and patient counseling.

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Authors: Soumya Mukherjee, Gnanamurthy Sivakumar, John R. Goodden, Atul K. Tyagi, and Paul D. Chumas

In Brief

The authors conducted a prospective study of isolated pediatric head injury involving analysis of a large cohort (201 children) and demonstrated that initial high blood white cell count has a predictive value for lengthy hospital stay and poor cognitive outcome in these children. This study is important because it represents the first prospective and large cohort study that supports the use of initial white cell count as a predictor of outcome in pediatric head injury.

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Authors: Ailish Coblentz, Gavin J. B. Elias, Alexandre Boutet, Jurgen Germann, Musleh Algarni, Lais M. Oliveira, Clemens Neudorfer, Elysa Widjaja, George M. Ibrahim, Suneil K. Kalia, Mehr Jain, Andres M. Lozano, and Alfonso Fasano

In Brief

The authors explored the functional and structural networks associated with improvement in children undergoing deep brain stimulation (DBS) for dystonia. The area most associated with clinical improvement was located in the posterior globus pallidus pars interna, with structural connectivity with the precentral and postcentral gyri, parietooccipital region, and brainstem. Scant information on the mechanisms of pediatric DBS is available and this study elucidates similarities and differences with the conventional target used for adult dystonia.

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Authors: Grégoire Boulouis, Sarah Stricker, Sandro Benichi, Jean-François Hak, Florent Gariel, Quentin Alias, Timothée de Saint Denis, Manoelle Kossorotoff, Fanny Bajolle, Lorenzo Garzelli, Kevin Beccaria, Giovanna Paternoster, Marie Bourgeois, Nicolas Garcelon, Annie Harroche, Rossella Letizia Mancusi, Nathalie Boddaert, Stephanie Puget, Francis Brunelle, Thomas Blauwblomme, and Olivier Naggara

In Brief

Researchers conducted a large cross-sectional cohort study pooled in a meta-analysis with existing literature to investigate the etiology of pediatric intracerebral hemorrhage. In all pooled studies, readily identifiable cerebral vascular lesions were the predominant cause, with arteriovenous malformations representing the most frequent subtype. These current data contribute adjusted estimates of the relative prevalence of the various etiologies of intracerebral hemorrhage in children and provide novel data on the increasing prevalence of vascular lesions as age increases during childhood.

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Authors: Zeferino Demartini Jr., Gelson Luis Koppe, Bernardo Corrêa de Almeida Teixeira, Adriano Keijiro, Alexandre Novicki Francisco, and Luana Antunes Maranha Gatto

In Brief

The goal of this study was to spread word of a new alternative for endovascular treatment of high-flow fistulas in children. This adjuvant maneuver provides safer coil placement. The value of this study is based on a cheap, simple, and relatively low-risk option for flow arrest during embolization of high-flow fistulas.

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Authors: Yumiko Komori, Masahiro Nonaka, Takamasa Kamei, Junichi Takeda, Tetsuo Hashiba, Kunikazu Yoshimura, and Akio Asai
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In Brief

The aim of this study was to evaluate the prevalence of postconcussive symptoms and their relation to health-related quality of life in pediatric and adolescent patients with mild traumatic brain injury (mTBI) with an indication for head CT imaging. Postconcussive symptoms were present in up to one-third of the patients and were significantly associated with decreased health-related quality of life. The authors report a considerable prevalence of postconcussive symptoms in the rarely studied subgroup of young mTBI patients receiving head CT imaging.

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In Brief

Researchers investigated phase-amplitude coupling of fast activity modulated by slow waves on scalp electroencephalography to evaluate the strength of the modulation index before and after disconnection surgery in children with intractable nonlesional epileptic spasms. A decreased modulation index value due to surgery correlates with good seizure outcomes. The modulation index may indicate epileptogenic neuronal modulation of the interhemispheric corpus callosum and intrahemispheric subcortical network for epileptic spasms.

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In Brief

The researchers evaluated the usefulness and applicability of available neurosurgical morbidity scoring scales in a large cohort of pediatric brain tumors from a single center; their results were favorably comparable to those in the literature. An improved tool to quantify morbidity from pediatric neurooncology is necessary to enable comparative surgical and unit data and reporting.

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In Brief

The authors sought to characterize the long-term rates of shunt infection and malfunction in myelomeningocele (MMC) patients before and after adoption of the Hydrocephalus Clinical Research Network (HCRN) standardized surgical protocols to reduce ventriculoperitoneal (VP) shunt infections. A 21% per person-year revision rate and 2.1% per person-year infection rate were determined in 137 patients with MMC and VP shunts, and both rates improved with adoption of the HCRN protocols. Shunt externalization prior to revision was found to be associated with a higher infection rate.

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In Brief

The authors examined the utility of ventriculogallbladder (VGB) shunts in a series of children with hydrocephalus resulting from intraventricular hemorrhage related to extreme prematurity. VGB shunts can serve as a definitive treatment or as a bridge procedure until the patient is larger and comorbid abdominal or vascular issues have resolved sufficiently to allow conversion back to ventriculoperitoneal or ventriculoatrial devices. VGB shunts should be considered earlier in the treatment of this difficult-to-manage group with hydrocephalus related to extreme prematurity.

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In Brief

Researchers used the Health Outcome Questionnaire (HOQ)–Spanish version to describe the health status of pediatric patients with hydrocephalus treated by endoscopic third ventriculostomy and to identify factors related to worse status. Possible factors related to worse outcomes were the presence of epilepsy, a prior valve, many surgical procedures, and communicating or secondary hydrocephalus. This study helps to identify clinical factors to address to improve the quality of life in pediatric patients, and use of the HOQ scale allows one to evaluate their evolution in an objective way and compare the health status between different populations.

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In Brief

The authors conducted this study to better clarify complication rates and symptom improvements for different kinds of dural graft materials used for posterior fossa decompression with duraplasty in patients with Chiari I malformation and syringomyelia. This study is important because complication rates for these different graft types are not well established and determining what may be the best graft types could be very beneficial to these patients.

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In Brief

Authors of this study evaluated the outcome of pediatric traumatic brain injury patients receiving low-molecular-weight heparin (LMWH) versus unfractionated heparin (UH). LMWH prophylaxis appeared to be more effective than UH at preventing venous thromboembolism with no increase in the mortality rate or the need for further surgical interventions to control hemorrhage in the LMWH group. These results need to be confirmed in large, prospective studies.

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In Brief

Clinical outcomes of patients undergoing shunt externalization were retrospectively reviewed to test the hypothesis that reimplantation with a ventriculoatrial shunt (VAS) rather than return to a ventriculoperitoneal shunt (VPS) is not associated with increased failure rate and may permit shorter externalization duration. There was no significant difference in shunt survival between patients with VASs and those with VPSs, although the externalization period was not shorter with VASs. Early conversion to a VAS may be a viable treatment option following shunt externalization.

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In Brief

The aim of this study was to evaluate a noninvasive biomarker (diffusion tensor imaging [DTI]) and establish its value as a predictor for the need of surgery for hydrocephalus in patients treated with prenatal repair of a myelomeningocele. DTI is an objective biomarker that significantly differentiates between prenatal myelomeningocele patients who need CSF diversion for hydrocephalus and those who do not. Ultimately, these results will help clinicians better evaluate and treat patients with myelomeningocele-associated hydrocephalus, thereby potentially avoiding the long–term neurocognitive ramifications of this lifelong condition.

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In Brief

The authors evaluated the preclinical efficacy of repurposing ribavirin, an FDA-approved antiviral drug, as a targeted therapeutic for the treatment of medulloblastoma. The results demonstrated in vitro that ribavirin reduced medulloblastoma cell growth, migration, and invasion and increased cell death. In vivo, ribavirin extended survival in an aggressive group 3 animal model. Ribavirin may be an appealing candidate for further study in medulloblastoma given its existing regulatory approval, safety profile, multitargeted activity, and radio- and chemosensitizing properties.

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In Brief

Researchers used a novel, fast MRI protocol that avoids sedation in pediatric brain injury. The goal of the study was to reduce radiation exposure while maintaining timeliness and improving the accuracy of imaging. MRI was superior to CT in demonstrating all intracranial hemorrhages, with excellent accuracy. This study shows the potential for the use of rapid MRI as a surveillance imaging tool in brain injury in order to reduce unnecessary radiation exposure from CT scans.

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In Brief

The authors evaluated whether operative decompression of Chiari 1.5 malformation in pediatric patients improved sleep-related breathing disorders and whether radiological parameters predicted improvement. This was the first series of pediatric patients with Chiari 1.5 malformations with sleep-related breathing disorders who demonstrated a marked improvement in their polysomnography results postdecompression. Improvements in sleep apnea may have a significant impact on children’s learning and development, further highlighting the importance of diagnosing the Chiari 1.5 malformation and sleep-related breathing disorders in affected children.

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In Brief

The authors analyzed the impact of standardization on surgical costs and outcomes. In the study, two groups of patients were compared, one before and one after implementation of a standardized shunt valve inventory. Findings from the study show that whereas there was no inferiority in outcomes from a limited shunt inventory, there was a significant decrease in costs.

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In Brief

Perioperative hypothermia is associated with increased surgical risk. The authors present an improvement in the perioperative care of pediatric patients undergoing instrumented spine surgery. Using a simplistic protocol, patients experienced improvement in the duration and severity of hypothermia from arrival to the operating room until the start of the operation. This was proven by comparing an observational cohort to an intervention group focused on tracking temperature as well as intentional warming, beginning in the preoperative area.

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In Brief

The authors studied the variable associated with hematoma evacuation in children with ruptured arteriovenous malformations. Determinants of hematoma evacuation were lower Glasgow Coma Scale score, higher intracerebral hemorrhage/brain volume ratio, superficial arteriovenous malformation location, and radiological signs of herniation. This study provides a framework for decision-making in pediatric ruptured arteriovenous malformation.

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In Brief

The authors assessed the safety and efficacy of corpus callosotomy performed with MR-guided laser interstitial thermal therapy (LITT) in pediatric patients with medically refractory epilepsy. The results of this novel retrospective analysis with long-term follow-up data from patients undergoing LITT or open corpus callosotomy (OCC) indicate that LITT is a safe and effective alternative to OCC. LITT demonstrates great promise as an alternative method for performing corpus callosotomy in carefully selected cases, but additional confirmation of LITT durability is needed.

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In Brief

The authors developed a set of standard work tools for performing dynamic stereo-electroencephalography. The standard work tools were used to implement this program at another institution with a similar efficiency and safety profile. It is hoped that widespread adoption of these standard work tools will facilitate multisite studies investigating focality.

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In Brief

The objective of this paper was to evaluate the clinical and hemodynamic benefits of an occipital artery–middle cerebral artery bypass for patients with pediatric moyamoya disease who had recurrent symptoms after initial revascularization. Cerebrovascular reactivity values in both middle cerebral artery and posterior cerebral artery territories are significantly improved, with clinical improvement after occipital artery–middle cerebral artery bypass despite progression of posterior cerebral artery stenosis in most patients. The occipital artery–middle cerebral artery bypass is an effective rescue therapy for cases of pediatric moyamoya disease.

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In Brief

The objective of this study was to compare the quality of imaging using EOS low-dose radiography to conventional radiography to evaluate peritoneal shunt tubing. The authors found that overall image quality and hardware delineation of EOS radiography did not significantly differ from conventional radiography for the evaluation of cerebral shunts. EOS appears to be a lower-cost and lower-radiation alternative to radiography for shunt evaluation.

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In Brief

The objective of this study was to use resting-state functional MRI to preoperatively map language networks in children with epilepsy. Language networks were identified at the individual level, and more than half of the cases in the study presented with atypical language lateralization, highlighting the need for brain mapping. Preoperatively identifying language networks in pediatric cases is challenging. However, it can help optimize electrode placement.

Restricted access

In Brief

Researchers conducted a large cross-sectional cohort study pooled in a meta-analysis with existing literature to investigate the etiology of pediatric intracerebral hemorrhage. In all pooled studies, readily identifiable cerebral vascular lesions were the predominant cause, with arteriovenous malformations representing the most frequent subtype. These current data contribute adjusted estimates of the relative prevalence of the various etiologies of intracerebral hemorrhage in children and provide novel data on the increasing prevalence of vascular lesions as age increases during childhood.

Restricted access

In Brief

The authors explored the functional and structural networks associated with improvement in children undergoing deep brain stimulation (DBS) for dystonia. The area most associated with clinical improvement was located in the posterior globus pallidus pars interna, with structural connectivity with the precentral and postcentral gyri, parietooccipital region, and brainstem. Scant information on the mechanisms of pediatric DBS is available and this study elucidates similarities and differences with the conventional target used for adult dystonia.

Restricted access

In Brief

The authors conducted a prospective study of isolated pediatric head injury involving analysis of a large cohort (201 children) and demonstrated that initial high blood white cell count has a predictive value for lengthy hospital stay and poor cognitive outcome in these children. This study is important because it represents the first prospective and large cohort study that supports the use of initial white cell count as a predictor of outcome in pediatric head injury.

Restricted access

In Brief

Researchers tested whether a noninvasive, non–contrast-based cerebral perfusion MRI technique, called arterial spin labeling (ASL), could detect the epileptogenic zone (EZ) in children with focal epilepsy who did not have obvious, well-defined structural brain lesions on MRI. Focal ASL abnormalities were found in over two-thirds of such cases and were concordant with the surgically proven EZ in 91% of children who underwent surgery. Due to the convenient and noninvasive nature of ASL, it may be reasonable to include this sequence in all routine MRIs done for focal epilepsy in children.

Restricted access

In Brief

The authors evaluated their series of vacuum-assisted elevation of skull fractures in pediatric patients and the variables affecting procedural outcomes. This study will add to the growing literature on the use of nonsurgical management of depressed skull fractures in pediatric patients and help practitioners with decision-making and patient counseling.

Restricted access

In Brief

The authors reviewed the literature to evaluate folate fortification and supplementation policies and their impact on reducing folate-sensitive neural tube defects (NTDs). Mandatory fortification was more effective than voluntary supplementation. Policies incorporating fortification and supplementation may optimally reduce folate-sensitive NTDs. Reductions in NTDs are cost-effective over time. A multimodal approach incorporating mandatory fortification, appropriate supplementation, and improved infrastructure and access to prenatal care to lead to decreased incidences of NTDs worldwide is optimal. This approach should be context-specific and culturally appropriate, with emphasis on education and consideration for local access to healthcare and social determinants of health.

Restricted access

In Brief

The goal of this study was to spread word of a new alternative for endovascular treatment of high-flow fistulas in children. This adjuvant maneuver provides safer coil placement. The value of this study is based on a cheap, simple, and relatively low-risk option for flow arrest during embolization of high-flow fistulas.

Restricted access

In Brief

The authors sought to compare the accuracy of boltless electrode placement with that of standard placement. Placing stereotactic EEG (SEEG) electrodes without anchor bolts is technically feasible. The accuracy of boltless electrodes was similar to that of electrodes placed with standard techniques. This technique allows electrodes to be placed in areas not amenable to standard techniques that utilize an anchor bolt, such as in very thin bone or the back of the head. This is the first description, to the authors’ knowledge, of such a technique being used in SEEG.

Restricted access

In Brief

The objective of the study was to characterize and understand risk factors of rapid shunt failure in pediatric hydrocephalus. Age at shunt insertion and etiology of hydrocephalus are key risk factors of fast and ultrafast shunt failure. Fast shunt failure is an unfortunately common event in pediatric hydrocephalus. This study has been an important step in defining the phenomenon and trying to understand risk factors for children who experience fast shunt failure.

Restricted access

In Brief

In this study, the authors defined a new variable, shunt failure cluster, to perform the first analysis of multiple and frequent shunt failures. They found that 6% of children with ventriculoperitoneal shunts have a cluster of shunt failures, and that these patients account for 30% of all shunt revisions. Risk factors for shunt failure cluster include prematurity and history of shunt infection.

Restricted access

In Brief

The authors examined trends in the surgical treatment of pediatric hydrocephalus over an 8-year period and found that important changes in the treatment of this condition have occurred over a very short time frame. This work represents the first study using high-quality registry data to examine changes in the surgical care of pediatric hydrocephalus in North America.

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In Brief

In this study the authors compared the survival between pediatric patients with high-grade gliomas who underwent gross-total resection after one or more reoperations versus those with subtotal resection. The authors found that median overall survival was 17 months, and progression-free survival was 10 months for all patients. The authors also found no differences in survival between patients with gross-total resection after reoperation when compared with those who achieved subtotal resection. These findings highlight the importance of the first attempt to remove the tumor, because the second surgery aiming to achieve gross-total resection may not provide the patient with longer survival.

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In Brief

Using finite element modeling techniques, the authors investigated craniocervical biomechanics in a pediatric patient with Down syndrome (DS). Two age-matched models with identical material properties, one of a patient with DS and one of a child without DS, were created and tested. The authors found increases in craniocervical motion with the DS model, supporting the hypothesis that bony geometry plays a large part in the excessive craniocervical motion that occurs in DS patients and calling into question the role of ligamentous laxity.

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In Brief

The authors present a novel method of extraoperative stereoelectroencephalography (SEEG) monitoring complemented by subsequent intraoperative recordings, designed to tailor multistaged resections in rolandic and perirolandic cortex in a highly selected group of patients with pharmacoresistant rolandic and perirolandic focal epilepsy. The results testified to the feasibility and demonstrated the value of the combined benefits of both extra- and intraoperative SEEG recordings when resecting the rolandic and perirolandic areas. With the proposed novel hybrid method one can precisely limit the volume of resection necessary to abort epileptic activity while preserving the functional cortex as much as possible.

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In Brief

Intrinsic epidermoid tumors of the brainstem are rare, histologically benign lesions associated with a high surgical morbidity and mortality due to their eloquent location. The authors describe a novel technique of endoscope-assisted microsurgery for managing symptomatic lesions and recommend a strategy of conservative surgery with resection of as much of the tumor capsule as is safely possible.

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In Brief

This paper’s objective is to demonstrate a novel innovative approach to tissue-sparing hemispherotomy in patients with intractable hemispheric epilepsy without a lateral ventricle. The surgery successfully disconnected the pathologic hemisphere and the patient has been seizure free with significant improvement in achieving developmental milestones. This technique illustrates a surgical disconnection option with low morbidity for patients who would otherwise undergo a hemispherectomy with a higher risk of significant morbidity and mortality.