Convection-enhanced delivery of botulinum toxin serotype A into the nonhuman primate cisterna magna and hippocampus.

Objective: Botulinum toxin serotype A (BoNT/A) was reported to raise the seizure threshold when injected into the seizure focus of a kindled rodent model. Delivering BoNT/A to the nonhuman primate (NHP) central nervous system via convection-enhanced delivery (CED) has not been performed. The objective of this study was to determine the toxicity and distribution characteristics of CED of BoNT/A into the NHP hippocampus and cisterna magna.

Complications following pediatric cranioplasty after decompressive craniectomy: a multicenter retrospective study.

OBJECTIVE In children, the repair of skull defects arising from decompressive craniectomy presents a unique set of challenges. Single-center studies have identified different risk factors for the common complications of cranioplasty resorption and infection. The goal of the present study was to determine the risk factors for bone resorption and infection after pediatric cranioplasty.

Growth and alignment of the pediatric subaxial cervical spine following rigid instrumentation and fusion: a multicenter study of the Pediatric Craniocervical Society.

OBJECTIVE The long-term effects of surgical fusion on the growing subaxial cervical spine are largely unknown. Recent cross-sectional studies have demonstrated that there is continued growth of the cervical spine through the teenage years. The purpose of this multicenter study was to determine the effects of rigid instrumentation and fusion on the growing subaxial cervical spine by investigating vertical growth, cervical alignment, cervical curvature, and adjacent-segment instability over time.

Pediatric Pituitary Adenoma: Case Series, Review of the Literature, and a Skull Base Treatment Paradigm.

 Pediatric pituitary adenoma is a rare skull base neoplasm, accounting for 3% of all intracranial neoplasms in children and 5% of pituitary adenomas. Compared with pituitary tumors in adults, secreting tumors predominate and longer disease trajectories are expected due to the patient age resulting in a natural history and treatment paradigm that is complex and controversial.  The aims of this study were to describe a large, single-institution series of pediatric pituitary adenomas with extensive long-term follow-up and to conduct a systematic review examining outcomes after pituitary adenoma surgery in the pediatric population.

Acute pressure changes in the brain are correlated with MR elastography stiffness measurements: initial feasibility in an in vivo large animal model.

Purpose: The homeostasis of intracranial pressure (ICP) is of paramount importance for maintaining normal brain function. A noninvasive technique capable of making direct measurements of ICP currently does not exist. MR elastography (MRE) is capable of noninvasively measuring brain tissue stiffness in vivo, and may act as a surrogate to measure ICP.

Clinical and surgical management of a congenital Type II split cord malformation presenting with progressive cranial neuropathies: case report.

Split cord malformation (SCM) is a rare abnormality of notochord development. The majority of cases occur in the thoracolumbar region, with more than 30 cases of cervical SCM reported. The clinical impact of SCMs involving the cervical cord is therefore largely unknown.

Accuracy of Pedicle Screw Placement in Children 10 Years or Younger Using Navigation and Intraoperative CT.

Study Design: A consecutive case series.

Objective: To determine the revision rate for pedicle screws placed using intraoperative CT and image-guided navigation in children 10 years or younger.

Summary Of Background Data: Screws are frequently used for spinal instrumentation in young children, although this is only by physician-directed use.

Current Selection Criteria and Perioperative Therapy Used for Fetal Myelomeningocele Surgery.

Objective: To determine the current maternal and fetal selection criteria and operative approaches used at centers performing fetal myelomeningocele surgery.

Methods: The 17 principal investigators participating in the Fetal Myelomeningocele Consortium were asked to participate in an anonymous online survey regarding the current practice of maternal-fetal surgery for neural tube defect repair and results were tabulated. The 35-question survey related to diagnostic testing, inclusion and exclusion criteria, and clinical management.

The rise and fall of the craniocervical junction relative to the hard palate: a lifetime story.

Object: Endoscopic approaches to the anterior craniocervical junction are increasing in frequency. Choice of oral versus endoscopic endonasal approach to the odontoid often depends on the relationship of the C1-2 complex to the hard palate. However, it is not known how this relevant anatomy changes with age.

Sports participation with Chiari I malformation.

OBJECT There is currently no consensus on the safety of sports participation for patients with Chiari I malformation (CM-I). The authors' goal was to define the risk of sports participation for children with the imaging finding of CM-I. METHODS A prospective survey was administered to 503 CM-I patients at 2 sites over a 46-month period.

Penetrating head injuries in children due to BB and pellet guns: a poorly recognized public health risk.

OBJECT Nonpowder guns, defined as spring- or gas-powered BB or pellet guns, can be dangerous weapons that are often marketed to children. In recent decades, advances in compressed-gas technology have led to a significant increase in the power and muzzle velocity of these weapons. The risk of intracranial injury in children due to nonpowder weapons is poorly documented.

Superficial siderosis of the central nervous system associated with incomplete dural closure following posterior fossa surgery: report of 3 cases.

This report reviews a series of 3 patients who developed superficial siderosis following posterior fossa operations in which dural closure was incomplete. In all 3 patients, revision surgery and complete duraplasty was performed to halt the progression of superficial siderosis. Following surgery, 2 patients experienced resolution of their CSF xanthochromia while 1 patient had reduced CSF xanthochromia.

Repeat resective surgery in complex pediatric refractory epilepsy: lessons learned.

OBJECT Resection can sometimes offer the best chance of meaningful seizure reduction in children with medically intractable epilepsy. However, when surgery fails to achieve the desired outcome, reoperation may be an option. The authors sought to investigate outcomes following resective reoperation in pediatric patients with refractory epilepsy, excluding tumoral epilepsies.

Degenerative changes in adolescent spines: a comparison of motocross racers and age-matched controls.

Object: Motocross racing is a popular sport; however, its impact on the growing/developing pediatric spine is unknown. Using a retrospective cohort model, the authors compared the degree of advanced degenerative findings in young motocross racers with findings in age-matched controls.

Methods: Patients who had been treated for motocross-related injury at the authors' institution between 2000 and 2007 and had been under 18 years of age at the time of injury and had undergone plain radiographic or CT examination of any spinal region were eligible for inclusion.

Factors contributing to the yield of asymmetric bilateral implantation of intracranial electrodes.

Objective: To determine the outcome of implanting fewer electrodes over the hemisphere with less supporting presurgical localizing data.

Methods: We retrospectively reviewed our epilepsy surgery database at Mayo Clinic, Rochester, Minnesota, between January 1, 1999, and December 31, 2011, to identify patients who had an asymmetric number of electrode contacts implanted in each hemisphere for seizure localization. We scored each presurgical noninvasive data point (0, 0.

Clinical outcomes of children and adults with central nervous system primitive neuroectodermal tumor.

Central nervous system primitive neuroectodermal tumors (CNS PNETs) predominantly occur in children and rarely in adults. Because of the rarity of this tumor, its outcomes and prognostic variables are not well characterized. The purpose of this study was to evaluate clinical outcomes and prognostic factors for children and adults with CNS PNET.

Diagnostic outcome of surgical revision of intracranial electrode placements for seizure localization.

Purpose: We aimed to determine the yield of revising intracranially implanted electrodes and the factors contributing to the yield.

Methods: Patients were identified from the Mayo Clinic Epilepsy Surgery Database between 1997 and 2010. Twenty patients had revision of intracranial electrode placements because initial implantation did not localize seizure onset adequately.

Chronic subthreshold subdural cortical stimulation for the treatment of focal epilepsy originating from eloquent cortex.

Medically refractory epilepsy remains a major medical problem worldwide. Although some patients are eligible for surgical resection of seizure foci, a proportion of patients are ineligible for a variety of reasons. One such reason is that the foci reside in eloquent cortex of the brain and therefore resection would result in significant morbidity.

Spinal stenosis frequent in children with multiple hereditary exostoses.

Purpose: Children with multiple hereditary exostoses (MHE) have numerous osteochondromas, with the most prominent lesions typically over the appendicular skeleton. A recent report noted a high rate of intracanal lesions in this patient population and recommended preventative spinal screening with magnetic resonance imaging (MRI) or computed tomography (CT). We sought to evaluate the prevalence of spinal stenosis from intracanal osteochondromas at our pediatric orthopedic center in order to evaluate if routine screening is warranted.

Seizure outcomes after corpus callosotomy for drop attacks.

Background: Medically intractable epilepsy involving drop attacks can be difficult to manage and negatively affect quality of life. Most studies investigating the effect of corpus callosotomy (CC) on seizures have been limited, focusing on the pediatric population or drop seizures alone, with little attention to other factors influencing seizure outcome.

Objective: To assess seizure outcomes after CC in adults and children.

The role of nocturnal polysomnography in assessing children with Chiari type I malformation.

Objective: To evaluate nocturnal polysomnogram findings in children with suspected symptomatic Chiari type I malformation, correlate them with clinical and magnetic resonance imaging data and to determine if this information has value in clinical decision making process.

Methods: A retrospective review identified 24 children with type I Chiari malformation, presumed symptomatic who had undergone neurological assessment, cranial magnetic resonance imaging and nocturnal polysomnography. Perimedullary subarachnoid space effacement on the magnetic resonance studies and the magnitude of cerebellar tonsillar descent in relation to the McRae line were correlated with frequency of obstructive or central sleep apnea, number of cortical arousals and evidence of impaired vocal mobility on laryngoscopy.

Histologically proven, low-grade brainstem gliomas in children: 30-year experience with long-term follow-up at Mayo Clinic.

Introduction: To evaluate long-term overall survival (OS), progression-free survival (PFS), and outcomes in pathologically proven brainstem low-grade gliomas (BS-LGG) in children.

Methods: The Mayo Clinic tumor registry identified 48 consecutive children (≤20 y, 52% female) with biopsy-proven BS-LGG treated at Mayo Clinic between January 1971 and December 2004. Medical records were retrospectively reviewed.