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Papers by Daniel Curry

Research paper thumbnail of Perioperative Costs between Stereotactic Laser Ablation and Craniotomy for Hypothalamic Hamartoma

Journal of Pediatric Epilepsy, 2017

Research paper thumbnail of EPEN-25. Exceptional Clinical and Imaging Response to TRK-Inhibition in a Patient with Supratentorial Ependymoma Harboring NTRK2 Gene Fusion

Neuro-Oncology, 2020

BACKGROUND Patients with metastatic pediatric ependymoma have limited therapeutic options and poo... more BACKGROUND Patients with metastatic pediatric ependymoma have limited therapeutic options and poor outcomes. Approximately ¾ of supratentorial ependymomas are driven by C11ORF95-RELA fusions, and the remaining by a heterogeneous group of fusion events. We present a six year-old male diagnosed with supratentorial ependymoma with leptomeningeal carcinomatosis harboring an NTRK2-fusion. Local and distant multifocal, intracranial and intraspinal tumor recurrence occurred seven months following gross total resection of the primary lesion and proton beam craniospinal irradiation. METHODS DNA and RNA from FFPE tumor were used for targeted sequencing using an 81-gene fusion panel and 124-gene mutation panel. Separately, capture transcriptome sequencing, exome sequencing, and copy number array were performed as part of the Texas KidsCanSeq study, an NHGRI/NCI-funded Clinical Sequencing Evidence-Generating Research (CSER) consortium project. All sequencing was carried out in CLIA-certified la...

Research paper thumbnail of Determination of Differences in Seed-Based Resting State Functional Magnetic Resonance Imaging Language Networks in Pediatric Patients with Left- and Right-Lateralized Language: A Pilot Study

Journal of Epilepsy Research, 2020

The current tools available for localization of expressive language, including functional magneti... more The current tools available for localization of expressive language, including functional magnetic resonance imaging (fMRI) and cortical stimulation mapping (CSM), require that the patient remain stationary and follow language commands with precise timing. Many pediatric epilepsy patients, however, have intact language skills but are unable to participate in these tasks due to cognitive impairments or young age. In adult subjects, there is evidence that language laterality can be determined by resting state (RS) fMRI activity, however there are few studies on the use of RS to accurately predict language laterality in children. Methods: A retrospective review of pediatric patients at Texas Children's Hospital was performed to identify patients who have undergone epilepsy surgical planning over 3 years with language localization using traditional methods of Wada testing, CSM, or task-based fMRI with calculated laterality index, as well as a 7-minute RS scan available without excessive motion or noise. We found the correlation between each subject's left and right Broca's region activity and each of 68 cortical regions. Results: A group of nine patients with left-lateralized language were found to have greater voxel-wise correlations than a group of six patients with right-lateralized language between a left hemispheric Broca's region seed and the following six cortical regions: left inferior temporal, left lateral orbitofrontal, left pars triangularis, right lateral orbitofrontal, right pars orbitalis and right superior frontal regions. Conclusions: In a cohort of children with epilepsy, we found that patients with left-and right-hemispheric language lateralization have different RS networks.

Research paper thumbnail of 139 Outcome of Stereotactic Laser Ablation of Primary Brain Tumors in Children

Neurosurgery, 2017

INTRODUCTION Stereotactic laser ablation (SLA) is an innovative minimally invasive strategy used ... more INTRODUCTION Stereotactic laser ablation (SLA) is an innovative minimally invasive strategy used to treat intracranial tumors. While it is applied commonly in adults as adjuvant therapy for high grade tumors, its use in children is less well understood. At Texas Children's Hospital (TCH), an interdisciplinary team considers SLA, with or without concomitant biopsy, as a diagnostic and treatment strategy in select cases. This study represents our institutional experience over 5 years using SLA for children with brain tumors. METHODS A retrospective chart review was performed for patients less than 18 years old undergoing SLA at TCH from 2012–2016. Demographics, medical history, and surgical outcomes were recorded. Biopsy diagnosis rate, adjuvant treatments, and tumor outcomes are noted. RESULTS >Fourteen children (7 males), with an average age at first surgery of 11.6 years, underwent SLA for WHO I (8), WHO II (1), WHO III (1), WHO IV (2) and unknown (2) tumors. Tumor locations...

Research paper thumbnail of Network‐targeted approach and postoperative resting‐state functional magnetic resonance imaging are associated with seizure outcome

Annals of Neurology, 2019

Objective: Postoperative resting-state functional magnetic resonance imaging (MRI) in children wi... more Objective: Postoperative resting-state functional magnetic resonance imaging (MRI) in children with intractable epilepsy has not been quantified in relation to seizure outcome. Therefore, its value as a biomarker for epileptogenic pathology is not well understood. Methods: In a sample of children with intractable epilepsy who underwent prospective resting-state seizure onset zone (SOZ)-targeted epilepsy surgery, postoperative resting-state functional MRI (rs-fMRI) was performed 6 to 12 months later. Graded normalization of the postoperative resting-state SOZ was compared to seizure outcomes, patient, surgery, and anatomical MRI characteristics. Results: A total of 64 cases were evaluated. Network-targeted surgery, followed by postoperative rs-fMRI normalization was significantly (p < 0.001) correlated with seizure reduction, with a Spearman rank correlation coefficient of 0.83. Of 39 cases with postoperative rs-fMRI SOZ normalization, 38 (97%) became completely seizure free. In contrast, of the 25 cases without complete rs-fMRI SOZ normalization, only 3 (5%) became seizure free. The accuracy of rs-fMRI as a biomarker predicting seizure freedom is 94%, with 96% sensitivity and 93% specificity. Interpretation: Among seizure localization techniques in pediatric epilepsy, network-targeted surgery, followed by postoperative rs-fMRI normalization, has high correlation with seizure freedom. This study shows that rs-fMRI SOZ can be used as a biomarker of the epileptogenic zone, and postoperative rs-fMRI normalization is a biomarker for SOZ quiescence.

Research paper thumbnail of Epilepsy outcome following resection of low-grade brain tumors in children

Journal of Neurosurgery: Pediatrics, 2019

OBJECTIVEThe indication for and timing of surgery for epilepsy associated with low-grade mixed ne... more OBJECTIVEThe indication for and timing of surgery for epilepsy associated with low-grade mixed neuronal-glial tumors may be controversial. The purpose of this study was to evaluate the effect of resection and associated variables on epilepsy and on progression-free survival (PFS).METHODSA retrospective chart review of patients treated between 1992 and 2016 was conducted to identify individuals with epilepsy and low-grade gliomas or neuronal-glial tumors who underwent resective surgery. Data analyzed included age at epilepsy onset, age at surgery, extent of resection, use of electrocorticography, the number of antiepileptic drugs (AEDs) before and after surgery, the presence of dysplasia, Engel class, histological findings, and PFS. The institutional review board protocol was specifically approved to conduct this study.RESULTSA total of 107 patients were identified. The median follow-up was 4.9 years. The most common pathology was dysembryoplastic neuroepithelial tumor (36.4%), follo...

Research paper thumbnail of Connectivity changes after laser ablation: Resting-state fMRI

Epilepsy research, Jan 28, 2017

Resting-state functional magnetic resonance imaging (rsfMRI) is emerging as a useful tool in the ... more Resting-state functional magnetic resonance imaging (rsfMRI) is emerging as a useful tool in the multimodal assessment of patients with epilepsy. In pediatric patients who cannot perform task-based fMRI, rsfMRI may present an adjunct and alternative. Although changes in brain activation during task-based fMRI have been described after surgery for epilepsy, there is limited data on the role of postoperative rsfMRI. In this short review, we discuss the role of postoperative rsfMRI after laser ablation of seizure foci. By establishing standardized anesthesia protocols and imaging parameters, we have been able to perform serial rsfMRI at postoperative follow-up. The development of in-house software that can merge rsfMRI images to surgical navigation systems has allowed us to enhance the clinical applications of this technique. Resting-state fMRI after laser ablation has the potential to identify changes in connectivity, localize new seizure foci, and guide antiepileptic therapy. In our ...

Research paper thumbnail of A standardized protocol to reduce pediatric baclofen pump infections: a quality improvement initiative

Journal of neurosurgery. Pediatrics, Jan 26, 2018

OBJECTIVE Intrathecal baclofen pumps are generally placed in children for the treatment of spasti... more OBJECTIVE Intrathecal baclofen pumps are generally placed in children for the treatment of spasticity and dystonia. Use of implants in this pediatric population with comorbidities is reported to have a high risk of complications and infections. With the aim of reducing baclofen pump-related infections, a quality improvement project was instituted at the authors' institution. METHODS A workflow paradigm unique to baclofen pump implantation aimed at decreasing implant-related infections was implemented. All baclofen pump operations performed at the authors' institution between August 2012 and June 2016 were reviewed. An infection prevention protocol was created and implemented in August 2014 based on a literature review and the consensus opinion of the pediatric neurosurgeons in the group. Compliance with the prevention bundle was tracked. Case outcomes before and after implementation of the protocol with a minimum of 3 months of follow-up were retrospectively reviewed. Univar...

Research paper thumbnail of Stereotyped high-frequency oscillations discriminate seizure onset zones and critical functional cortex in focal epilepsy

Brain : a journal of neurology, Jan 30, 2018

High-frequency oscillations in local field potentials recorded with intracranial EEG are putative... more High-frequency oscillations in local field potentials recorded with intracranial EEG are putative biomarkers of seizure onset zones in epileptic brain. However, localized 80-500 Hz oscillations can also be recorded from normal and non-epileptic cerebral structures. When defined only by rate or frequency, physiological high-frequency oscillations are indistinguishable from pathological ones, which limit their application in epilepsy presurgical planning. We hypothesized that pathological high-frequency oscillations occur in a repetitive fashion with a similar waveform morphology that specifically indicates seizure onset zones. We investigated the waveform patterns of automatically detected high-frequency oscillations in 13 epilepsy patients and five control subjects, with an average of 73 subdural and intracerebral electrodes recorded per patient. The repetitive oscillatory waveforms were identified by using a pipeline of unsupervised machine learning techniques and were then correla...

Research paper thumbnail of High-frequency oscillations detected in ECoG recordings correlate with cavernous malformation and seizure-free outcome in a child with focal epilepsy: A case report

Epilepsia Open, 2017

Epilepsy associated with cavernous malformation (CM) often requires surgical resection of seizure... more Epilepsy associated with cavernous malformation (CM) often requires surgical resection of seizure focus to achieve seizure-free outcome. High-frequency oscillations (HFOs) in intracranial electroencephalogram (EEG) are reported as potential biomarkers of epileptogenic regions, but to our knowledge there are no data on the existence of HFOs in CM-caused epilepsy. Here we report our experience of the identification of the seizure focus in a 3-year-old pediatric patient with intractable epilepsy associated with CM. The electrocorticographic recordings were obtained from a 64contact grid over 2 days in the epilepsy monitoring unit (EMU). The spatial distribution of HFOs and epileptic spikes were estimated from recording segments right after the electrode placement, during sleep and awake states separately. The HFO distribution showed consistency with the perilesional region; the location of spikes varied over days and did not correlate with the lesion. The HFO spatial distribution was more compact in sleep state and pinpointed the contacts sitting on the CM border. Following the resection of the CM and the hemosiderin ring, the patient became seizure-free. This is the first report describing HFOs in a pediatric patient with intractable epilepsy associated with CM and shows their potential in identifying the seizure focus.

Research paper thumbnail of Correlating Resting-State Functional Magnetic Resonance Imaging Connectivity by Independent Component Analysis-Based Epileptogenic Zones with Intracranial Electroencephalogram Localized Seizure Onset Zones and Surgical Outcomes in Prospective Pediatric Intractable Epilepsy Study

Brain Connectivity, 2017

The purpose of this study was to prospectively investigate the agreement between the epileptogeni... more The purpose of this study was to prospectively investigate the agreement between the epileptogenic zone(s) (EZ) localization by resting-state functional magnetic resonance imaging (rs-fMRI) and the seizure onset zone(s) (SOZ) identified by intracranial electroencephalogram (ic-EEG) using novel differentiating and ranking criteria of rs-fMRI abnormal independent components (ICs) in a large consecutive heterogeneous pediatric intractable epilepsy population without an a priori alternate modality informing EZ localization or prior declaration of total SOZ number. The EZ determination criteria were developed by using independent component analysis (ICA) on rs-fMRI in an initial cohort of 350 pediatric patients evaluated for epilepsy surgery over a 3-year period. Subsequently, these rs-fMRI EZ criteria were applied prospectively to an evaluation cohort of 40 patients who underwent ic-EEG for SOZ identification. Thirty-seven of these patients had surgical resection/disconnection of the area believed to be the primary source of seizures. One-year seizure frequency rate was collected postoperatively. Among the total 40 patients evaluated, agreement between rs-fMRI EZ and ic-EEG SOZ was 90% (36/40; 95% confidence interval [CI], 0.76-0.97). Of the 37 patients who had surgical destruction of the area believed to be the primary source of seizures, 27 (73%) rs-fMRI EZ could be classified as true positives, 7 (18%) false positives, and 2 (5%) false negatives. Sensitivity of rs-fMRI EZ was 93% (95% CI 78-98%) with a positive predictive value of 79% (95% CI, 63-89%). In those with cryptogenic localization-related epilepsy, agreement between rs-fMRI EZ and ic-EEG SOZ was 89% (8/9; 95% CI, 0.52-99), with no statistically significant difference between the agreement in the cryptogenic and symptomatic localization-related epilepsy subgroups. Two children with negative ic-EEG had removal of the rs-fMRI EZ and were seizure free 1 year postoperatively. Of the 33 patients where at least 1 rs-fMRI EZ agreed with the ic-EEG SOZ, 24% had at least 1 additional rs-fMRI EZ outside the resection area. Of these patients with un-resected rs-fMRI EZ, 75% continued to have seizures 1 year later. Conversely, among 75% of patients in whom rs-fMRI agreed with ic-EEG SOZ and had no anatomically separate rs-fMRI EZ, only 24% continued to have seizures 1 year later. This relationship between extraneous rs-fMRI EZ and seizure outcome was statistically significant (p = 0.01).

Research paper thumbnail of Ankyrin-G isoform imbalance and interneuronopathy link epilepsy and bipolar disorder

Molecular Psychiatry, 2016

ANK3, encoding the adaptor protein Ankyrin-G, has been implicated in bipolar disorder by genome w... more ANK3, encoding the adaptor protein Ankyrin-G, has been implicated in bipolar disorder by genome wide association studies. ANK3 has multiple alternative first exons, and a bipolar disorder-associated ANK3 variant has been shown to reduce expression of exon 1b. Here we identify mechanisms through which reduced ANK3 exon 1b isoform expression disrupts neuronal excitation-inhibition balance. We find that parvalbumin interneurons and principal cells differentially express ANK3 first exon subtypes. Parvalbumin interneurons express only isoforms containing exon 1b, whereas excitatory principal cells express exon 1e alone, or both 1e and 1b. In transgenic mice deficient for exon 1b, parvalbumin interneurons lack voltage-gated sodium channels at their axonal initial segments and have increased firing thresholds and diminished action potential dynamic range. These mice exhibit an Ank3 gene dosage-dependent phenotype including behavior changes modeling bipolar disorder, epilepsy, and sudden death. Thus, ANK3's important association with human bipolar susceptibility may arise from imbalance between ankyrin-G function in interneurons and principal cells and resultant excessive circuit sensitivity and output. Ankyrin-G isoform imbalance is a novel molecular endophenotype and potential therapeutic target. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

Research paper thumbnail of Comparison of Perioperative Costs between Stereotactic Laser Ablation and Craniotomy for Hypothalamic Hamartoma

Journal of Pediatric Epilepsy, 2017

Hypothalamic hamartoma (HH) is a congenital intracranial lesion associated with precocious pubert... more Hypothalamic hamartoma (HH) is a congenital intracranial lesion associated with precocious puberty and gelastic epilepsy in children. Surgical management of HH to treat refractory epilepsy is a mainstay of treatment. Our aim was to compare the demographic characteristics and perioperative costs associated with resection by craniotomy and stereotactic laser ablation (SLA) by reviewing our institutional experience with SLA and comparing these data to a national database for craniotomy and resection. Retrospective chart review was conducted for the Texas Children's Hospital cohort of patients who underwent SLA for HH between 2011 and 2013. Information about the craniotomy cohort representing historical cases of craniotomy was obtained from the Kids' Inpatient Database for years 2003, 2006, and 2009. The cohort definition for patients undergoing craniotomy for HH was modified from published adult literature to identify pediatric patients with refractory epilepsy secondary to HH. Our study has shown that children undergoing SLA for HH have a shorter length of stay and lower cost of hospitalization compared with those who underwent craniotomy and resection for the same diagnosis. Together with previous findings from our institution regarding the safety and efficacy of SLA, our findings suggest that SLA may represent an attractive alternative to craniotomy for the treatment of refractory epilepsy secondary to HH.

Research paper thumbnail of Perioperative antibiotic use in vagus nerve stimulator implantation: a clinical series

Child's Nervous System, 2017

Preoperative antibiosis contributes up to one third of total antibiotic use in major hospitals. C... more Preoperative antibiosis contributes up to one third of total antibiotic use in major hospitals. Choice of antibiotic is not uniformly standardized, and polypharmacy regimens may be used without knowing the effect on rates of surgical site infection, nonsurgical infections, or antibiotic resistance. Careful examination of trends in surgical prophylaxis is warranted. In this study, we aimed to examine our institution&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s experience with vagus nerve stimulator (VNS) implantation, focusing on association between perioperative antibiotic practices and postoperative infectious outcomes. We conducted a single-center case-control study using a retrospective chart review of 50 consecutively operated patients undergoing VNS implantation over 24 months by two experienced surgeons at our institution from April 2014 to March 2016. In each surgery, the technical procedure, operating room, and surgical team were the same, while surgeon&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s preference in antibiotic prophylaxis differed. Group 1 received a single dose of intravenous (IV) cefazolin (n = 26), and Group 2 received IV cefazolin, paired with one or both of gentamicin/vancomycin, in addition to a 10-day outpatient oral course of clindamycin (n = 24). Patient demographics, perioperative details, and minimum 3-month follow-up for infection and healthcare utilization were recorded. Student t tests were computed for significance. Group 1 patients on average were older than group 2 patients (10.2, 7.1 years, p = 0.01), and length of surgery was longer (115.5, 91.9 min, p = 0.007). There were no differences in number of surgeons gowned (p = 0.11), presence of tracheostomy (p = 0.43) or gastrostomy (p = 0.20) tube, nonsurgical infections (p = 0.32), and number of postoperative emergency department (ED) visits (p = 0.22) or readmissions (p = 0.23). Neither group had VNS infections in the follow-up period. Single preoperative dosing of one antibiotic appropriately chosen to cover typical skin flora conferred equal benefit to perioperative prophylactic polypharmacy in this study. There were no differences in postoperative infection events or ED visits/readmissions. Restraint with preoperative antibiosis shows equipoise in postoperative infection and overall resource utilization.

Research paper thumbnail of Rasmussen encephalitis tissue transfer program

Epilepsia, Jun 1, 2016

Rasmussen encephalitis tissue transfer program DISCLOSURE OF CONFLICT OF INTEREST Gary Mathern se... more Rasmussen encephalitis tissue transfer program DISCLOSURE OF CONFLICT OF INTEREST Gary Mathern serves on the Editorial Board and International League Against Epilepsy (ILAE) Executive Committee for Epilepsia. William D. Gaillard and Adam L. Hartman serve on the Editorial Board for Epilepsia. The remaining authors have no conflicts of interest. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

Research paper thumbnail of Revision surgeries following vagus nerve stimulator implantation

Journal of Clinical Neuroscience, 2016

The vagus nerve stimulator (VNS) has been shown to provide a safe, albeit costly, treatment for i... more The vagus nerve stimulator (VNS) has been shown to provide a safe, albeit costly, treatment for intractable epilepsy. We aimed to analyze the incidence, timing, and clinical/demographic associations of revision surgery post-VNS implantation in epilepsy patients. The Thomson Reuters MarketScan database, containing data from 23-50million individuals, was used. Epilepsy patients receiving VNS implantations from 2003 to 2009 were identified by Current Procedural Terminology and International Classification Of Diseases Ninth Revision codes. Incidence and timing of subsequent implant-related surgeries were recorded. Events were described using time-to-event methodology, with Kaplan-Meier failure estimation/Cox proportional hazard models adjusted for clinical/demographic factors. In 1234 patients, average incidence of revision surgeries over 6years of follow-up were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1%, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3%, 4-10%, and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1% for VNS electrode revision, battery revision/removal, battery replacement/implantation, and infection washout, respectively. For electrode revision and battery revision/replacement, the incidence was higher in the first year and for battery replacement in later years. Age, sex, insurance type, or geographic region did not significantly impact event occurrence. Implant-related revision surgeries are rare. Some events occur more often in certain follow-up years than others; none are significantly impacted by age, sex, insurance type, or geographic region. The most common reason for revision was battery replacement several years after VNS placement.

Research paper thumbnail of Trends in outcomes, complications, and hospitalization costs for hemispherectomy in the United States for the years 2000-2009

Epilepsia, 2015

Hemispherectomy is an established surgical treatment for carefully selected pediatric patients wi... more Hemispherectomy is an established surgical treatment for carefully selected pediatric patients with intractable epilepsy. Published perioperative data report low mortality rates and seizure reduction rates of 50-89%. This study investigates trends in the demographics, hospital utilization, and in-hospital complication rates of patients undergoing hemispherectomy over the past decade in the United States, using the nationally representative Kids' Inpatient Database (KID). The KID was queried for all discharges with the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure code for hemispherectomy in the years 2000, 2003, 2006, and 2009. The patient cohorts from these four time points were compared, analyzing differences in demographic data, insurance and payer status, total cost, length of stay, in-hospital mortality, and complications. National estimates and 95% confidence intervals are reported given the weighted sample design of K...

Research paper thumbnail of The surfactant poloxamer-188 protects against glutamate toxicity in the rat brain

NeuroReport, 2004

Membrane repair of damaged neurons by surfactant poloxamers has been noted in experimental spinal... more Membrane repair of damaged neurons by surfactant poloxamers has been noted in experimental spinal cord injury and in vitro excitotoxicity.We examined poloxamer-188 (P-188)-mediated neuroprotection in a rat model of glutamate toxicity. Quinolinate was infused into the striatum followed10 min and 4 h later by P-188 administered either i.v. or intracisternally (i.c.), or by vehicle. Mean neuronal loss examined volumetrically 7 days later in control animals was 50% greater (Po0.01) than after i.c. P-188 treatment; control lesion volumes were 38% greater than lesion volumes after i.v. P-188 treatment; however, that comparison did not reach signi¢cance. This robust protection against glutamate toxicity may predict P-188-mediated neuroprotection against a broad range of clinically relevant neural insults. NeuroReport 15:171^174 c 2004 Lippincott Williams & Wilkins.

Research paper thumbnail of Medulloblastoma and juvenile pilocytic astrocytoma presenting as synchronous primary brain tumors in a child

Journal of Neurosurgery: Pediatrics, 2010

Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological typ... more Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological type have been published in the adult and pediatric literature. However, the simultaneous occurrence of multiple primary brain tumors with different cell types is rare. Even more rare is the pediatric presentation of multiple primary brain tumors with different cell types. The authors describe the case of an 8-year-old boy who presented with a 2-week history of progressive headache, nausea and vomiting, and imbalance. Brain MR imaging demonstrated a heterogeneously enhancing mixed solid/cystic mass of the left cerebellar hemisphere and a larger, midline, more homogeneously enhancing lesion of the superior vermis. Spinal MR imaging was unremarkable. The patient underwent a suboccipital craniotomy and subsequent gross-total resection of both mass lesions. Pathological examination revealed the left cerebellar and superior vermian lesions to be a juvenile pilocytic astrocytoma and a medulloblas...

Research paper thumbnail of Synthes Award for Resident Research in Brain and Craniofacial Injury: poloxamer 188 volumetrically decreases neuron loss in the rat model of excitotoxicity in a time-dependent manner

Clinical neurosurgery, 2003

Research paper thumbnail of Perioperative Costs between Stereotactic Laser Ablation and Craniotomy for Hypothalamic Hamartoma

Journal of Pediatric Epilepsy, 2017

Research paper thumbnail of EPEN-25. Exceptional Clinical and Imaging Response to TRK-Inhibition in a Patient with Supratentorial Ependymoma Harboring NTRK2 Gene Fusion

Neuro-Oncology, 2020

BACKGROUND Patients with metastatic pediatric ependymoma have limited therapeutic options and poo... more BACKGROUND Patients with metastatic pediatric ependymoma have limited therapeutic options and poor outcomes. Approximately ¾ of supratentorial ependymomas are driven by C11ORF95-RELA fusions, and the remaining by a heterogeneous group of fusion events. We present a six year-old male diagnosed with supratentorial ependymoma with leptomeningeal carcinomatosis harboring an NTRK2-fusion. Local and distant multifocal, intracranial and intraspinal tumor recurrence occurred seven months following gross total resection of the primary lesion and proton beam craniospinal irradiation. METHODS DNA and RNA from FFPE tumor were used for targeted sequencing using an 81-gene fusion panel and 124-gene mutation panel. Separately, capture transcriptome sequencing, exome sequencing, and copy number array were performed as part of the Texas KidsCanSeq study, an NHGRI/NCI-funded Clinical Sequencing Evidence-Generating Research (CSER) consortium project. All sequencing was carried out in CLIA-certified la...

Research paper thumbnail of Determination of Differences in Seed-Based Resting State Functional Magnetic Resonance Imaging Language Networks in Pediatric Patients with Left- and Right-Lateralized Language: A Pilot Study

Journal of Epilepsy Research, 2020

The current tools available for localization of expressive language, including functional magneti... more The current tools available for localization of expressive language, including functional magnetic resonance imaging (fMRI) and cortical stimulation mapping (CSM), require that the patient remain stationary and follow language commands with precise timing. Many pediatric epilepsy patients, however, have intact language skills but are unable to participate in these tasks due to cognitive impairments or young age. In adult subjects, there is evidence that language laterality can be determined by resting state (RS) fMRI activity, however there are few studies on the use of RS to accurately predict language laterality in children. Methods: A retrospective review of pediatric patients at Texas Children's Hospital was performed to identify patients who have undergone epilepsy surgical planning over 3 years with language localization using traditional methods of Wada testing, CSM, or task-based fMRI with calculated laterality index, as well as a 7-minute RS scan available without excessive motion or noise. We found the correlation between each subject's left and right Broca's region activity and each of 68 cortical regions. Results: A group of nine patients with left-lateralized language were found to have greater voxel-wise correlations than a group of six patients with right-lateralized language between a left hemispheric Broca's region seed and the following six cortical regions: left inferior temporal, left lateral orbitofrontal, left pars triangularis, right lateral orbitofrontal, right pars orbitalis and right superior frontal regions. Conclusions: In a cohort of children with epilepsy, we found that patients with left-and right-hemispheric language lateralization have different RS networks.

Research paper thumbnail of 139 Outcome of Stereotactic Laser Ablation of Primary Brain Tumors in Children

Neurosurgery, 2017

INTRODUCTION Stereotactic laser ablation (SLA) is an innovative minimally invasive strategy used ... more INTRODUCTION Stereotactic laser ablation (SLA) is an innovative minimally invasive strategy used to treat intracranial tumors. While it is applied commonly in adults as adjuvant therapy for high grade tumors, its use in children is less well understood. At Texas Children's Hospital (TCH), an interdisciplinary team considers SLA, with or without concomitant biopsy, as a diagnostic and treatment strategy in select cases. This study represents our institutional experience over 5 years using SLA for children with brain tumors. METHODS A retrospective chart review was performed for patients less than 18 years old undergoing SLA at TCH from 2012–2016. Demographics, medical history, and surgical outcomes were recorded. Biopsy diagnosis rate, adjuvant treatments, and tumor outcomes are noted. RESULTS >Fourteen children (7 males), with an average age at first surgery of 11.6 years, underwent SLA for WHO I (8), WHO II (1), WHO III (1), WHO IV (2) and unknown (2) tumors. Tumor locations...

Research paper thumbnail of Network‐targeted approach and postoperative resting‐state functional magnetic resonance imaging are associated with seizure outcome

Annals of Neurology, 2019

Objective: Postoperative resting-state functional magnetic resonance imaging (MRI) in children wi... more Objective: Postoperative resting-state functional magnetic resonance imaging (MRI) in children with intractable epilepsy has not been quantified in relation to seizure outcome. Therefore, its value as a biomarker for epileptogenic pathology is not well understood. Methods: In a sample of children with intractable epilepsy who underwent prospective resting-state seizure onset zone (SOZ)-targeted epilepsy surgery, postoperative resting-state functional MRI (rs-fMRI) was performed 6 to 12 months later. Graded normalization of the postoperative resting-state SOZ was compared to seizure outcomes, patient, surgery, and anatomical MRI characteristics. Results: A total of 64 cases were evaluated. Network-targeted surgery, followed by postoperative rs-fMRI normalization was significantly (p < 0.001) correlated with seizure reduction, with a Spearman rank correlation coefficient of 0.83. Of 39 cases with postoperative rs-fMRI SOZ normalization, 38 (97%) became completely seizure free. In contrast, of the 25 cases without complete rs-fMRI SOZ normalization, only 3 (5%) became seizure free. The accuracy of rs-fMRI as a biomarker predicting seizure freedom is 94%, with 96% sensitivity and 93% specificity. Interpretation: Among seizure localization techniques in pediatric epilepsy, network-targeted surgery, followed by postoperative rs-fMRI normalization, has high correlation with seizure freedom. This study shows that rs-fMRI SOZ can be used as a biomarker of the epileptogenic zone, and postoperative rs-fMRI normalization is a biomarker for SOZ quiescence.

Research paper thumbnail of Epilepsy outcome following resection of low-grade brain tumors in children

Journal of Neurosurgery: Pediatrics, 2019

OBJECTIVEThe indication for and timing of surgery for epilepsy associated with low-grade mixed ne... more OBJECTIVEThe indication for and timing of surgery for epilepsy associated with low-grade mixed neuronal-glial tumors may be controversial. The purpose of this study was to evaluate the effect of resection and associated variables on epilepsy and on progression-free survival (PFS).METHODSA retrospective chart review of patients treated between 1992 and 2016 was conducted to identify individuals with epilepsy and low-grade gliomas or neuronal-glial tumors who underwent resective surgery. Data analyzed included age at epilepsy onset, age at surgery, extent of resection, use of electrocorticography, the number of antiepileptic drugs (AEDs) before and after surgery, the presence of dysplasia, Engel class, histological findings, and PFS. The institutional review board protocol was specifically approved to conduct this study.RESULTSA total of 107 patients were identified. The median follow-up was 4.9 years. The most common pathology was dysembryoplastic neuroepithelial tumor (36.4%), follo...

Research paper thumbnail of Connectivity changes after laser ablation: Resting-state fMRI

Epilepsy research, Jan 28, 2017

Resting-state functional magnetic resonance imaging (rsfMRI) is emerging as a useful tool in the ... more Resting-state functional magnetic resonance imaging (rsfMRI) is emerging as a useful tool in the multimodal assessment of patients with epilepsy. In pediatric patients who cannot perform task-based fMRI, rsfMRI may present an adjunct and alternative. Although changes in brain activation during task-based fMRI have been described after surgery for epilepsy, there is limited data on the role of postoperative rsfMRI. In this short review, we discuss the role of postoperative rsfMRI after laser ablation of seizure foci. By establishing standardized anesthesia protocols and imaging parameters, we have been able to perform serial rsfMRI at postoperative follow-up. The development of in-house software that can merge rsfMRI images to surgical navigation systems has allowed us to enhance the clinical applications of this technique. Resting-state fMRI after laser ablation has the potential to identify changes in connectivity, localize new seizure foci, and guide antiepileptic therapy. In our ...

Research paper thumbnail of A standardized protocol to reduce pediatric baclofen pump infections: a quality improvement initiative

Journal of neurosurgery. Pediatrics, Jan 26, 2018

OBJECTIVE Intrathecal baclofen pumps are generally placed in children for the treatment of spasti... more OBJECTIVE Intrathecal baclofen pumps are generally placed in children for the treatment of spasticity and dystonia. Use of implants in this pediatric population with comorbidities is reported to have a high risk of complications and infections. With the aim of reducing baclofen pump-related infections, a quality improvement project was instituted at the authors' institution. METHODS A workflow paradigm unique to baclofen pump implantation aimed at decreasing implant-related infections was implemented. All baclofen pump operations performed at the authors' institution between August 2012 and June 2016 were reviewed. An infection prevention protocol was created and implemented in August 2014 based on a literature review and the consensus opinion of the pediatric neurosurgeons in the group. Compliance with the prevention bundle was tracked. Case outcomes before and after implementation of the protocol with a minimum of 3 months of follow-up were retrospectively reviewed. Univar...

Research paper thumbnail of Stereotyped high-frequency oscillations discriminate seizure onset zones and critical functional cortex in focal epilepsy

Brain : a journal of neurology, Jan 30, 2018

High-frequency oscillations in local field potentials recorded with intracranial EEG are putative... more High-frequency oscillations in local field potentials recorded with intracranial EEG are putative biomarkers of seizure onset zones in epileptic brain. However, localized 80-500 Hz oscillations can also be recorded from normal and non-epileptic cerebral structures. When defined only by rate or frequency, physiological high-frequency oscillations are indistinguishable from pathological ones, which limit their application in epilepsy presurgical planning. We hypothesized that pathological high-frequency oscillations occur in a repetitive fashion with a similar waveform morphology that specifically indicates seizure onset zones. We investigated the waveform patterns of automatically detected high-frequency oscillations in 13 epilepsy patients and five control subjects, with an average of 73 subdural and intracerebral electrodes recorded per patient. The repetitive oscillatory waveforms were identified by using a pipeline of unsupervised machine learning techniques and were then correla...

Research paper thumbnail of High-frequency oscillations detected in ECoG recordings correlate with cavernous malformation and seizure-free outcome in a child with focal epilepsy: A case report

Epilepsia Open, 2017

Epilepsy associated with cavernous malformation (CM) often requires surgical resection of seizure... more Epilepsy associated with cavernous malformation (CM) often requires surgical resection of seizure focus to achieve seizure-free outcome. High-frequency oscillations (HFOs) in intracranial electroencephalogram (EEG) are reported as potential biomarkers of epileptogenic regions, but to our knowledge there are no data on the existence of HFOs in CM-caused epilepsy. Here we report our experience of the identification of the seizure focus in a 3-year-old pediatric patient with intractable epilepsy associated with CM. The electrocorticographic recordings were obtained from a 64contact grid over 2 days in the epilepsy monitoring unit (EMU). The spatial distribution of HFOs and epileptic spikes were estimated from recording segments right after the electrode placement, during sleep and awake states separately. The HFO distribution showed consistency with the perilesional region; the location of spikes varied over days and did not correlate with the lesion. The HFO spatial distribution was more compact in sleep state and pinpointed the contacts sitting on the CM border. Following the resection of the CM and the hemosiderin ring, the patient became seizure-free. This is the first report describing HFOs in a pediatric patient with intractable epilepsy associated with CM and shows their potential in identifying the seizure focus.

Research paper thumbnail of Correlating Resting-State Functional Magnetic Resonance Imaging Connectivity by Independent Component Analysis-Based Epileptogenic Zones with Intracranial Electroencephalogram Localized Seizure Onset Zones and Surgical Outcomes in Prospective Pediatric Intractable Epilepsy Study

Brain Connectivity, 2017

The purpose of this study was to prospectively investigate the agreement between the epileptogeni... more The purpose of this study was to prospectively investigate the agreement between the epileptogenic zone(s) (EZ) localization by resting-state functional magnetic resonance imaging (rs-fMRI) and the seizure onset zone(s) (SOZ) identified by intracranial electroencephalogram (ic-EEG) using novel differentiating and ranking criteria of rs-fMRI abnormal independent components (ICs) in a large consecutive heterogeneous pediatric intractable epilepsy population without an a priori alternate modality informing EZ localization or prior declaration of total SOZ number. The EZ determination criteria were developed by using independent component analysis (ICA) on rs-fMRI in an initial cohort of 350 pediatric patients evaluated for epilepsy surgery over a 3-year period. Subsequently, these rs-fMRI EZ criteria were applied prospectively to an evaluation cohort of 40 patients who underwent ic-EEG for SOZ identification. Thirty-seven of these patients had surgical resection/disconnection of the area believed to be the primary source of seizures. One-year seizure frequency rate was collected postoperatively. Among the total 40 patients evaluated, agreement between rs-fMRI EZ and ic-EEG SOZ was 90% (36/40; 95% confidence interval [CI], 0.76-0.97). Of the 37 patients who had surgical destruction of the area believed to be the primary source of seizures, 27 (73%) rs-fMRI EZ could be classified as true positives, 7 (18%) false positives, and 2 (5%) false negatives. Sensitivity of rs-fMRI EZ was 93% (95% CI 78-98%) with a positive predictive value of 79% (95% CI, 63-89%). In those with cryptogenic localization-related epilepsy, agreement between rs-fMRI EZ and ic-EEG SOZ was 89% (8/9; 95% CI, 0.52-99), with no statistically significant difference between the agreement in the cryptogenic and symptomatic localization-related epilepsy subgroups. Two children with negative ic-EEG had removal of the rs-fMRI EZ and were seizure free 1 year postoperatively. Of the 33 patients where at least 1 rs-fMRI EZ agreed with the ic-EEG SOZ, 24% had at least 1 additional rs-fMRI EZ outside the resection area. Of these patients with un-resected rs-fMRI EZ, 75% continued to have seizures 1 year later. Conversely, among 75% of patients in whom rs-fMRI agreed with ic-EEG SOZ and had no anatomically separate rs-fMRI EZ, only 24% continued to have seizures 1 year later. This relationship between extraneous rs-fMRI EZ and seizure outcome was statistically significant (p = 0.01).

Research paper thumbnail of Ankyrin-G isoform imbalance and interneuronopathy link epilepsy and bipolar disorder

Molecular Psychiatry, 2016

ANK3, encoding the adaptor protein Ankyrin-G, has been implicated in bipolar disorder by genome w... more ANK3, encoding the adaptor protein Ankyrin-G, has been implicated in bipolar disorder by genome wide association studies. ANK3 has multiple alternative first exons, and a bipolar disorder-associated ANK3 variant has been shown to reduce expression of exon 1b. Here we identify mechanisms through which reduced ANK3 exon 1b isoform expression disrupts neuronal excitation-inhibition balance. We find that parvalbumin interneurons and principal cells differentially express ANK3 first exon subtypes. Parvalbumin interneurons express only isoforms containing exon 1b, whereas excitatory principal cells express exon 1e alone, or both 1e and 1b. In transgenic mice deficient for exon 1b, parvalbumin interneurons lack voltage-gated sodium channels at their axonal initial segments and have increased firing thresholds and diminished action potential dynamic range. These mice exhibit an Ank3 gene dosage-dependent phenotype including behavior changes modeling bipolar disorder, epilepsy, and sudden death. Thus, ANK3's important association with human bipolar susceptibility may arise from imbalance between ankyrin-G function in interneurons and principal cells and resultant excessive circuit sensitivity and output. Ankyrin-G isoform imbalance is a novel molecular endophenotype and potential therapeutic target. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

Research paper thumbnail of Comparison of Perioperative Costs between Stereotactic Laser Ablation and Craniotomy for Hypothalamic Hamartoma

Journal of Pediatric Epilepsy, 2017

Hypothalamic hamartoma (HH) is a congenital intracranial lesion associated with precocious pubert... more Hypothalamic hamartoma (HH) is a congenital intracranial lesion associated with precocious puberty and gelastic epilepsy in children. Surgical management of HH to treat refractory epilepsy is a mainstay of treatment. Our aim was to compare the demographic characteristics and perioperative costs associated with resection by craniotomy and stereotactic laser ablation (SLA) by reviewing our institutional experience with SLA and comparing these data to a national database for craniotomy and resection. Retrospective chart review was conducted for the Texas Children's Hospital cohort of patients who underwent SLA for HH between 2011 and 2013. Information about the craniotomy cohort representing historical cases of craniotomy was obtained from the Kids' Inpatient Database for years 2003, 2006, and 2009. The cohort definition for patients undergoing craniotomy for HH was modified from published adult literature to identify pediatric patients with refractory epilepsy secondary to HH. Our study has shown that children undergoing SLA for HH have a shorter length of stay and lower cost of hospitalization compared with those who underwent craniotomy and resection for the same diagnosis. Together with previous findings from our institution regarding the safety and efficacy of SLA, our findings suggest that SLA may represent an attractive alternative to craniotomy for the treatment of refractory epilepsy secondary to HH.

Research paper thumbnail of Perioperative antibiotic use in vagus nerve stimulator implantation: a clinical series

Child's Nervous System, 2017

Preoperative antibiosis contributes up to one third of total antibiotic use in major hospitals. C... more Preoperative antibiosis contributes up to one third of total antibiotic use in major hospitals. Choice of antibiotic is not uniformly standardized, and polypharmacy regimens may be used without knowing the effect on rates of surgical site infection, nonsurgical infections, or antibiotic resistance. Careful examination of trends in surgical prophylaxis is warranted. In this study, we aimed to examine our institution&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s experience with vagus nerve stimulator (VNS) implantation, focusing on association between perioperative antibiotic practices and postoperative infectious outcomes. We conducted a single-center case-control study using a retrospective chart review of 50 consecutively operated patients undergoing VNS implantation over 24 months by two experienced surgeons at our institution from April 2014 to March 2016. In each surgery, the technical procedure, operating room, and surgical team were the same, while surgeon&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s preference in antibiotic prophylaxis differed. Group 1 received a single dose of intravenous (IV) cefazolin (n = 26), and Group 2 received IV cefazolin, paired with one or both of gentamicin/vancomycin, in addition to a 10-day outpatient oral course of clindamycin (n = 24). Patient demographics, perioperative details, and minimum 3-month follow-up for infection and healthcare utilization were recorded. Student t tests were computed for significance. Group 1 patients on average were older than group 2 patients (10.2, 7.1 years, p = 0.01), and length of surgery was longer (115.5, 91.9 min, p = 0.007). There were no differences in number of surgeons gowned (p = 0.11), presence of tracheostomy (p = 0.43) or gastrostomy (p = 0.20) tube, nonsurgical infections (p = 0.32), and number of postoperative emergency department (ED) visits (p = 0.22) or readmissions (p = 0.23). Neither group had VNS infections in the follow-up period. Single preoperative dosing of one antibiotic appropriately chosen to cover typical skin flora conferred equal benefit to perioperative prophylactic polypharmacy in this study. There were no differences in postoperative infection events or ED visits/readmissions. Restraint with preoperative antibiosis shows equipoise in postoperative infection and overall resource utilization.

Research paper thumbnail of Rasmussen encephalitis tissue transfer program

Epilepsia, Jun 1, 2016

Rasmussen encephalitis tissue transfer program DISCLOSURE OF CONFLICT OF INTEREST Gary Mathern se... more Rasmussen encephalitis tissue transfer program DISCLOSURE OF CONFLICT OF INTEREST Gary Mathern serves on the Editorial Board and International League Against Epilepsy (ILAE) Executive Committee for Epilepsia. William D. Gaillard and Adam L. Hartman serve on the Editorial Board for Epilepsia. The remaining authors have no conflicts of interest. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

Research paper thumbnail of Revision surgeries following vagus nerve stimulator implantation

Journal of Clinical Neuroscience, 2016

The vagus nerve stimulator (VNS) has been shown to provide a safe, albeit costly, treatment for i... more The vagus nerve stimulator (VNS) has been shown to provide a safe, albeit costly, treatment for intractable epilepsy. We aimed to analyze the incidence, timing, and clinical/demographic associations of revision surgery post-VNS implantation in epilepsy patients. The Thomson Reuters MarketScan database, containing data from 23-50million individuals, was used. Epilepsy patients receiving VNS implantations from 2003 to 2009 were identified by Current Procedural Terminology and International Classification Of Diseases Ninth Revision codes. Incidence and timing of subsequent implant-related surgeries were recorded. Events were described using time-to-event methodology, with Kaplan-Meier failure estimation/Cox proportional hazard models adjusted for clinical/demographic factors. In 1234 patients, average incidence of revision surgeries over 6years of follow-up were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1%, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3%, 4-10%, and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1% for VNS electrode revision, battery revision/removal, battery replacement/implantation, and infection washout, respectively. For electrode revision and battery revision/replacement, the incidence was higher in the first year and for battery replacement in later years. Age, sex, insurance type, or geographic region did not significantly impact event occurrence. Implant-related revision surgeries are rare. Some events occur more often in certain follow-up years than others; none are significantly impacted by age, sex, insurance type, or geographic region. The most common reason for revision was battery replacement several years after VNS placement.

Research paper thumbnail of Trends in outcomes, complications, and hospitalization costs for hemispherectomy in the United States for the years 2000-2009

Epilepsia, 2015

Hemispherectomy is an established surgical treatment for carefully selected pediatric patients wi... more Hemispherectomy is an established surgical treatment for carefully selected pediatric patients with intractable epilepsy. Published perioperative data report low mortality rates and seizure reduction rates of 50-89%. This study investigates trends in the demographics, hospital utilization, and in-hospital complication rates of patients undergoing hemispherectomy over the past decade in the United States, using the nationally representative Kids' Inpatient Database (KID). The KID was queried for all discharges with the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure code for hemispherectomy in the years 2000, 2003, 2006, and 2009. The patient cohorts from these four time points were compared, analyzing differences in demographic data, insurance and payer status, total cost, length of stay, in-hospital mortality, and complications. National estimates and 95% confidence intervals are reported given the weighted sample design of K...

Research paper thumbnail of The surfactant poloxamer-188 protects against glutamate toxicity in the rat brain

NeuroReport, 2004

Membrane repair of damaged neurons by surfactant poloxamers has been noted in experimental spinal... more Membrane repair of damaged neurons by surfactant poloxamers has been noted in experimental spinal cord injury and in vitro excitotoxicity.We examined poloxamer-188 (P-188)-mediated neuroprotection in a rat model of glutamate toxicity. Quinolinate was infused into the striatum followed10 min and 4 h later by P-188 administered either i.v. or intracisternally (i.c.), or by vehicle. Mean neuronal loss examined volumetrically 7 days later in control animals was 50% greater (Po0.01) than after i.c. P-188 treatment; control lesion volumes were 38% greater than lesion volumes after i.v. P-188 treatment; however, that comparison did not reach signi¢cance. This robust protection against glutamate toxicity may predict P-188-mediated neuroprotection against a broad range of clinically relevant neural insults. NeuroReport 15:171^174 c 2004 Lippincott Williams & Wilkins.

Research paper thumbnail of Medulloblastoma and juvenile pilocytic astrocytoma presenting as synchronous primary brain tumors in a child

Journal of Neurosurgery: Pediatrics, 2010

Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological typ... more Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological type have been published in the adult and pediatric literature. However, the simultaneous occurrence of multiple primary brain tumors with different cell types is rare. Even more rare is the pediatric presentation of multiple primary brain tumors with different cell types. The authors describe the case of an 8-year-old boy who presented with a 2-week history of progressive headache, nausea and vomiting, and imbalance. Brain MR imaging demonstrated a heterogeneously enhancing mixed solid/cystic mass of the left cerebellar hemisphere and a larger, midline, more homogeneously enhancing lesion of the superior vermis. Spinal MR imaging was unremarkable. The patient underwent a suboccipital craniotomy and subsequent gross-total resection of both mass lesions. Pathological examination revealed the left cerebellar and superior vermian lesions to be a juvenile pilocytic astrocytoma and a medulloblas...

Research paper thumbnail of Synthes Award for Resident Research in Brain and Craniofacial Injury: poloxamer 188 volumetrically decreases neuron loss in the rat model of excitotoxicity in a time-dependent manner

Clinical neurosurgery, 2003