Clinical characteristics and outcome of central nervous system tumors harboring NTRK gene fusions.

Purpose: TRK fusions are detected in less than 2% of central nervous system tumors. There are limited data on the clinical course of affected patients.

Experimental Design: We conducted an international retrospective cohort study of patients with TRK fusion-driven CNS tumors.

GABA receptor outward currents are transiently disclosed by the convulsant 4-aminopyridine .

The K channel blocker 4-aminopyridine (4AP) has been extensively used to investigate the mechanisms underlying neuronal network synchronization in both and animal models of focal epilepsy. 4AP-induced effects are paralleled by an increase in both excitatory and inhibitory neurotransmitter release, but the mechanisms of action of 4AP on neuronal networks remain unclear. By employing simultaneous whole-cell patch clamp and field potential recordings from hippocampal CA3/4 pyramidal layer of acute brain slices obtained from mice (n = 30), we found that the appearance of epileptiform discharges induced by 4AP (100 μM) is consistently preceded by the transient recurrence of presumptive GABA outward currents, which are not mirrored by any field activity.

mTOR Pathway Somatic Pathogenic Variants in Focal Malformations of Cortical Development: Novel Variants, Topographic Mapping, and Clinical Outcomes.

Background And Objectives: Somatic and germline pathogenic variants in genes of the mammalian target of rapamycin (mTOR) signaling pathway are a common mechanism underlying a subset of focal malformations of cortical development (FMCDs) referred to as mTORopathies, which include focal cortical dysplasia (FCD) type II, subtypes of polymicrogyria, and hemimegalencephaly. Our objective is to screen resected FMCD specimens with mTORopathy features on histology for causal somatic variants in mTOR pathway genes, describe novel pathogenic variants, and examine the variant distribution in relation to neuroimaging, histopathologic classification, and clinical outcomes.

Methods: We performed ultra-deep sequencing using a custom HaloPlex Target Enrichment kit in DNA from 21 resected fresh-frozen histologically confirmed FCD type II, tuberous sclerosis complex, or hemimegalencephaly specimens.

Vasospasm following brain tumor resection in children: institutional experience and systematic review.

Objective: Delayed cerebral ischemia (DCI) associated with vasospasm is well described in the setting of aneurysmal subarachnoid hemorrhage (SAH). In addition, DCI is very infrequently encountered in patients who have undergone resection of a brain tumor with unclear pathophysiology. The occurrence of DCI in the pediatric population is exceedingly rare, and outcomes in this population have, to the authors' knowledge, never been systematically reviewed.

Subtle magnetic resonance imaging differences in tegmental pilocytic astrocytomas as a caution against attempting gross-total resection: illustrative cases.

Background: Although surgery within the tegmentum of the midbrain is challenging, resection of tegmental pilocytic astrocytomas (PAs) is a standard treatment because this has been shown to outperform chemotherapy and radiotherapy in terms of long-term tumor control. Gross total resection (GTR) assisted by intraoperative neuroelectrophysiological monitoring can be achieved with a reasonable risk-to-benefit ratio, especially for well-circumscribed tumors, but careful scrutiny of magnetic resonance imaging (MRI) is critical to surgical decision making. The authors present two cases of tegmental PAs, which appeared grossly similar on MRI and were operated on via the same surgical approach using the same intraoperative adjuncts.

K27M in canonical and noncanonical H3 variants occurs in distinct oligodendroglial cell lineages in brain midline gliomas.

Canonical (H3.1/H3.2) and noncanonical (H3.

Successful treatment of non-midline primary malignant germ cell tumors with yolk sac components in neonates: report of 2 cases.

Here, the authors present 2 cases of nongerminomatous germ cell tumor (NGGCT): a neonate with a mixed malignant germ cell tumor, 5% yolk sac tumor (YST) and 95% immature teratoma components, originating from the right mesial temporal lobe; and a 2-month-old infant with a pure YST originating from the left middle cranial fossa. These tumors with yolk sac components, which are thought to have a poor prognosis, were successfully treated with complete tumor resection alone and subtotal tumor resection with chemotherapy, respectively. Event-free survival exceeds 5 years for each patient even though neither received radiotherapy.

Operative Time as the Predominant Risk Factor for Transfusion Requirements in Nonsyndromic Craniosynostosis Repair.

Unlabelled: Despite recent advances in surgical, anesthetic, and safety protocols in the management of nonsyndromic craniosynostosis (NSC), significant rates of intraoperative blood loss continue to be reported by multiple centers. The purpose of the current study was to examine our center's experience with the surgical correction of NSC in an effort to determine independent risk factors of transfusion requirements.

Methods: A retrospective cohort study of patients with NSC undergoing surgical correction at the Montreal Children's Hospital was carried out.

Correction to: Efficacy of Dabrafenib for three children with brainstem BRAF positive ganglioglioma.

In the original article, the author names were published incorrectly. The names are correct in this publication.

Stalled developmental programs at the root of pediatric brain tumors.

Childhood brain tumors have suspected prenatal origins. To identify vulnerable developmental states, we generated a single-cell transcriptome atlas of >65,000 cells from embryonal pons and forebrain, two major tumor locations. We derived signatures for 191 distinct cell populations and defined the regional cellular diversity and differentiation dynamics.

Selective Dorsal Root Rhizotomy for Spastic Cerebral Palsy: A Longitudinal Case-Control Analysis of Functional Outcome.

Background: The benefit of selective dorsal rhizotomies (SDR) on motor function relative to the cerebral palsy (CP) natural history remains unknown.

Objective: To determine the functional benefit of SDR over the longitudinal CP natural history.

Methods: Retrospective, single-center, case-control study of patients post-SDR after 1990.

Efficacy of Dabrafenib for three children with brainstem BRAF positive ganglioglioma.

Purpose: Children with unresectable brainstem-infiltrated ganglioglioma have poor progression-free survival when treated with conventional chemotherapy and radiation regimens. The BRAF mutation occurs in a large number of gangliogliomas, making them amenable for targeted therapy using mutation-specific kinase inhibitors. However, limited data exists on the effectiveness and best treatment duration of these inhibitors in this tumor setting.

Hyperacute Infarct on Intraoperative Diffusion Imaging of Pediatric Brain Tumor Surgery.

Background: Brain neoplasms are the second-most prevalent cancer of childhood for which surgical resection remains the main treatment. Intraoperative MRI is a useful tool to optimize brain tumor resection. It is, however, not known whether intraoperative MRI can detect complications such as hyperacute ischemic infarcts.

Routine Postoperative Admission to the Intensive Care Unit Following Repair of Nonsyndromic Craniosynostosis: Is it Necessary?

Background: Cranial vault surgery for craniosynostosis is generally managed postoperatively in the intensive care unit (ICU). The purpose of the present study was to examine our center's experience with the postoperative management of otherwise healthy patients with nonsyndromic craniosynostosis (NSC) without routine ICU admission.

Methods: A retrospective cohort study of patients with NSC operated using a variety of vault reshaping techniques in our pediatric center between 2009 and 2017 was carried out.

Trametinib for progressive pediatric low-grade gliomas.

Introduction: Pediatric pilocytic astrocytomas (PAs) are low grade gliomas and the most common brain tumors in children. They often represent a therapeutic challenge when incompletely resected as they can recur and progress despite the use of several lines of chemotherapeutic agents or even radiation therapy. Genetic alterations leading to activation of the mitogen-activated-protein-kinase pathway are a hallmark of this disease and offer an interesting therapeutic alternative through the use of targeted inhibitors.

Magnetic Resonance Myelography in Congenital Absence of the Cervical Pedicle.

Absence of the cervical pedicle is a very rare congenital anomaly, easily misrecognized as a unilateral facet dislocation in a setting of acute trauma or a neoplastic process like a nerve sheath tumor. Although correct diagnosis can be achieved on the cervical radiograph and confirmed by the CT, MRI Myelography is clearly of additional value because shows the specific relationship and orientation of the nerve roots. To the best to our knowledge, this is the first description of MR Myelography findings.

3-T intraoperative MRI (iMRI) for pediatric epilepsy surgery.

Purpose: Three-tesla intraoperative MRI (iMRI) is a promising tool that could help confirm complete resections and disconnections in pediatric epilepsy surgery, leading to improved outcomes. However, a large proportion of epileptogenic pathologies in children are poorly defined on imaging, which brings into question the utility of iMRI for these cases. Our aim was to compare postoperative seizure outcomes between iMRI- and non-iMRI-based epilepsy surgeries.

Feasibility and value of preoperative embolization of a congenital choroid plexus tumour in the premature infant: An illustrative case report with technical details.

We present a case of a preterm boy (born at 35 weeks of pregnancy) who was delivered urgently by a caesarean section due to placental abruption. The baby was found to have a tense fontanelle leading to imaging that showed a 5.5 cm right intraventricular mass centred in the atrium, hydrocephalus and extensive surrounding vasogenic oedema.

Comprehensive analysis of the clinical and urodynamic outcomes of secondary tethered spinal cord before and after spinal cord untethering.

Objective: Secondary tethering of the spinal cord (TSC) occurs in 3-30% of patients with history of spinal cord dysraphism repair. As many patients with spinal cord dysraphism already have symptoms, it might be difficult to diagnose secondary TSC. Regular clinical/urodynamic (UDS) evaluation is therefore advised to pick-up changes early before they progress.

Non-random aneuploidy specifies subgroups of pilocytic astrocytoma and correlates with older age.

Pilocytic astrocytoma (PA) is the most common brain tumor in children but is rare in adults, and hence poorly studied in this age group. We investigated 222 PA and report increased aneuploidy in older patients. Aneuploid genomes were identified in 45% of adult compared with 17% of pediatric PA.

A comparison and cost analysis of cranioplasty techniques: autologous bone versus custom computer-generated implants.

Background: Cranioplasty can be performed either with gold-standard, autologous bone grafts and osteotomies or alloplastic materials in skeletally mature patients. Recently, custom computer-generated implants (CCGIs) have gained popularity with surgeons because of potential advantages, which include preoperatively planned contour, obviated donor-site morbidity, and operative time savings. A remaining concern is the cost of CCGI production.

Evidence from unilateral lesions of early uncompensable implementation of opposed response-biases in each hemisphere of the brain.

Purpose: The intact right hemisphere presents an omissive response-bias and the left hemisphere a commissive response-bias in adults. This research sought to determine whether these hemispherically lateralized response-biases manifest early developmental and uncompensable brain implementation.

Methods: Sixteen teenager and adult participants with focal left hemisphere lesions and fourteen with focal right hemisphere lesions (all with childhood onset: M=13 year recovery period) and 14 normal control participants were recruited.