Prospects of CSF shunt independence among chronically shunted patients.

BACKGROUND AND OBJECTIVES: CSF shunt placement for hydrocephalus and other etiologies has arguably been the most life-saving intervention in pediatric neurosurgery in the past 6 decades. Yet, chronic shunting remains a source of morbidity for patients of all ages. Neuroendoscopic surgery has made shunt independence possible for newly diagnosed hydrocephalic patients. In this study, we examine the prospects of shunt independence with or without endoscopic third ventriculostomy (ETV) in chronically shunted patients. METHODS: After IRB approval, a retrospective analysis was completed on patients whose shunt was ligated or removed to achieve shunt independence, with or without ETV. Clinical and imaging data were collected. RESULTS: Eighty-eight patients with CSF shunts had their shunt either ligated or removed, 57 of whom had a concomitant ETV. Original reasons for shunting included: congenital hydrocephalus 20 (23%), post-hemorrhagic hydrocephalus (PHH) of prematurity 14 (16%), aqueductal stenosis 10 (11%), intracranial cyst 8 (9%), tumor 8 (9%), infantile subdural hematomas 8 (9%), myelomeningocele 7 (8%), post-traumatic hydrocephalus 7 (8%) and post-infectious hydrocephalus 6 (7%). The decision to perform a simultaneous ETV was made based on etiology. Forty-nine (56%) patients became shunt independent. The success rate was 46% in the ETV group and 73% in the no ETV group. Using multivariate analysis and Cox Proportional Hazards models, age > 4 months at shunt placement (p = 0.032), no shunt revisions (p = 0.01), select etiologies (p = 0.043), and ETVSS > 70 (in the ETV group) (p = 0.017), were protective factors for shunt independence. CONCLUSION: Considering the long-term complications of shunting, achieving shunt independence may provide hope for improved quality of life. While this study is underpowered, it provides pilot data identifying factors that predict shunt independence in chronically shunted patients, namely age, absence of prior shunt revision, etiology, and in the ETV group, the ETVSS.

Nitrous Oxide Impairs Axon Regeneration after Nervous System Injury in Male Rats.

BACKGROUND: Nitrous oxide can induce neurotoxicity. The authors hypothesized that exposure to nitrous oxide impairs axonal regeneration and functional recovery after central nervous system injury. METHODS: The consequences of single and serial in vivo nitrous oxide exposures on axon regeneration in four experimental male rat models of nervous system injury were measured: in vitro axon regeneration in cell culture after in vivo nitrous oxide administration, in vivo axon regeneration after sharp spinal cord injury, in vivo axon regeneration after sharp optic nerve injury, and in vivo functional recovery after blunt contusion spinal cord injury. RESULTS: In vitro axon regeneration 48 h after a single in vivo 70% N2O exposure is less than half that in the absence of nitrous oxide (mean ± SD, 478 ± 275 um; n = 48) versus 210 ± 152 um (n = 48; P < 0.0001). A single exposure to 80% N2O inhibits the beneficial effects of folic acid on in vivo axonal regeneration after sharp spinal cord injury (13.4 ± 7.1% regenerating neurons [n = 12] vs. 0.6 ± 0.7% regenerating neurons [n = 4], P = 0.004). Serial 80% N2O administration reverses the benefit of folic acid on in vivo retinal ganglion cell axon regeneration after sharp optic nerve injury (1277 ± 180 regenerating retinal ganglion cells [n = 7] vs. 895 ± 164 regenerating retinal ganglion cells [n = 7], P = 0.005). Serial 80% N2O exposures reverses the benefit of folic acid on in vivo functional recovery after blunt spinal cord contusion (estimate for fixed effects ± standard error of the estimate: folic acid 5.60 ± 0.54 [n = 9] vs. folic acid + 80% N2O 5.19 ± 0.62 [n = 7], P < 0.0001). CONCLUSIONS: These data indicate that nitrous oxide can impair the ability of central nervous system neurons to regenerate axons after sharp and blunt trauma.

Syringomyelia in hereditary multiple exostosis.

We describe five children with Hereditary Multiple Exostosis (HME) who also had syringomyelia. Of these, four had a tethered cord/fibrolipoma. No spinal osteochondromas were found in these patients. All had antecedent neurological signs or symptoms that prompted spinal imaging with MRI. Of all patients with HME seen in the Midwest Regional Bone Dysplasia Clinic from 1982 to present, 44% (17/39) of patients had signs or symptoms concerning for possible cord-related neurological findings. However, only 10 of 39 had spinal imaging. Assuming that all individuals with syringomyelia were identified, then 5/39 (13%) were in that way affected. This, of course, is a minimal estimate given that many were not imaged. The incidence of syringomyelia appears to be increased in this population, and seems to be unrelated to spinal osteochondromas. A low threshold for obtaining spinal MRI in patients with Hereditary Multiple Exostosis seems rational. © 2016 Wiley Periodicals, Inc.

Cerebrospinal fluid flow impedance is elevated in Type I Chiari malformation.

Diagnosis of Type I Chiari malformation (CMI) is difficult because the most commonly used diagnostic criterion, cerebellar tonsillar herniation (CTH) greater than 3-5 mm past the foramen magnum, has been found to have little correlation with patient symptom severity. Thus, there is a need to identify new objective measurement(s) to help quantify CMI severity. This study investigated longitudinal impedance (LI) as a parameter to assess CMI in terms of impedance to cerebrospinal fluid motion near the craniovertebral junction. LI was assessed in CMI patients (N = 15) and age-matched healthy controls (N = 8) using computational fluid dynamics based on subject-specific magnetic resonance imaging (MRI) measurements of the cervical spinal subarachnoid space. In addition, CTH was measured for each subject. Mean LI in the CMI group (551 ± 66 dyn/cm5) was significantly higher than in controls (220 ± 17 dyn/cm5, p < 0.001). Mean CTH in the CMI group was 9.0 ± 1.1 mm compared to -0.4 ± 0.5 mm in controls. Regression analysis of LI versus CTH found a weak relationship (R2 = 0.46, p < 0.001), demonstrating that CTH was not a good indicator of the impedance to CSF motion caused by cerebellar herniation. These results showed that CSF flow impedance was elevated in CMI patients and that LI provides different information than a standard CTH measurement. Further research is necessary to determine if LI can be useful in CMI patient diagnosis.

Mother-Daughter Ventricular Endoscopy: A Technical Note and 2-Dimensional Video.

BACKGROUND AND IMPORTANCE: While navigating the ventricles with a rigid endoscope provides excellent visualization and the ability to use endoscopic instruments for complex surgery, these endoscopes are often too large to navigate tight areas. We present a surgical video showing the technique of mother-daughter endoscopy, which consists of the introduction of a flexible 1-mm fiberoptic endoscope through the channel of a large rigid endoscope to allow visualization across small spaces or channels, in this case, the cerebral aqueduct. This combination of superior visualization and handling of rigid endoscopes and flexibility and small size of fiberoptic endoscopes enhances safety and broadens possibilities in ventricular surgery. CLINICAL PRESENTATION: A 64-year-old woman with prior endoscopic aqueductoplasty for triventricular hydrocephalus and a failed endoscopic third ventriculostomy presented with focal restenosis of the aqueduct. A repeat endoscopic aqueductoplasty with stent placement were performed. Mother-daughter endoscopy was used to explore the occluded aqueduct for improved safety before fenestration and to ensure proper stent placement after fenestration. CONCLUSION: Mother-daughter endoscopy can add safety to complex or high-risk endoscopic procedures, particularly those with tight spaces that the large mother endoscope cannot visualize.

Reduction cranioplasty for hydrocephalic macrocephaly: a systematic review of surgical outcomes.

OBJECTIVE: Hydrocephalic macrocephaly can result in poor psychosocial development, positioning difficulties, skin breakdown, and poor cosmesis. Although reduction cranioplasty can address these sequelae, the postoperative outcomes, complications, and mortality risk of reduction cranioplasty are not well understood given the rarity of hydrocephalic macrocephaly. Therefore, the primary objective of this systematic review was to evaluate the surgical outcomes of reduction cranioplasty for the treatment of hydrocephalic macrocephaly. METHODS: A systematic review was performed using the PubMed, Scopus, and Web of Science databases while following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two independent reviewers screened 350 studies; 27 studies reporting surgical outcomes on reduction cranioplasty for hydrocephalic macrocephaly met inclusion criteria. Data on study design, patient demographics, operative details, and surgical outcomes were collected. RESULTS: There were 65 reduction cranioplasties among the 27 included studies. Eighteen (66.7%) studies presented level V evidence, 7 (25.9%) presented level IV evidence, and 2 (7.4%) presented level III evidence. Following reduction cranioplasty, there was improvement in postoperative head positioning in 23 (85.2%) studies, improvement in postoperative cosmesis in 22 (81.5%) studies, and improvement in global postoperative neurological functioning in 20 (74.1%) studies. The median estimated blood loss was 633 mL (range 20-2600 mL). Shunt revisions were the most common complication, reported in 9 (47.4%) of the 19 studies assessing complications. Of the 65 patients, there was a mortality rate of 6.2% (n = 4). CONCLUSIONS: The majority of the included studies reported improvement in head size, head positioning, cranial cosmesis, and global neurological functioning following reduction cranioplasty for hydrocephalic macrocephaly. However, the prevalence of lower-level evidence, risk of blood loss, complications, and mortality indicates the need for a serious discussion of surgical indication, an experienced team, and thorough perioperative planning to perform these complex surgeries.

RosetteArray® Platform for Quantitative High-Throughput Screening of Human Neurodevelopmental Risk.

Neural organoids have revolutionized how human neurodevelopmental disorders (NDDs) are studied. Yet, their utility for screening complex NDD etiologies and in drug discovery is limited by a lack of scalable and quantifiable derivation formats. Here, we describe the RosetteArray® platform's ability to be used as an off-the-shelf, 96-well plate assay that standardizes incipient forebrain and spinal cord organoid morphogenesis as micropatterned, 3-D, singularly polarized neural rosette tissues (>9000 per plate). RosetteArrays are seeded from cryopreserved human pluripotent stem cells, cultured over 6-8 days, and immunostained images can be quantified using artificial intelligence-based software. We demonstrate the platform's suitability for screening developmental neurotoxicity and genetic and environmental factors known to cause neural tube defect risk. Given the presence of rosette morphogenesis perturbation in neural organoid models of NDDs and neurodegenerative disorders, the RosetteArray platform could enable quantitative high-throughput screening (qHTS) of human neurodevelopmental risk across regulatory and precision medicine applications.

The role of occipital condyle and atlas anomalies on occipital cervical fusion outcomes in Chiari malformation type I with syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: Congenital anomalies of the atlanto-occipital articulation may be present in patients with Chiari malformation type I (CM-I). However, it is unclear how these anomalies affect the biomechanical stability of the craniovertebral junction (CVJ) and whether they are associated with an increased incidence of occipitocervical fusion (OCF) following posterior fossa decompression (PFD). The objective of this study was to determine the prevalence of condylar hypoplasia and atlas anomalies in children with CM-I and syringomyelia. The authors also investigated the predictive contribution of these anomalies to the occurrence of OCF following PFD (PFD+OCF). METHODS: The authors analyzed the prevalence of condylar hypoplasia and atlas arch anomalies for patients in the Park-Reeves Syringomyelia Research Consortium database who underwent PFD+OCF. Condylar hypoplasia was defined by an atlanto-occipital joint axis angle (AOJAA) ≥ 130°. Atlas assimilation and arch anomalies were identified on presurgical radiographic imaging. This PFD+OCF cohort was compared with a control cohort of patients who underwent PFD alone. The control group was matched to the PFD+OCF cohort according to age, sex, and duration of symptoms at a 2:1 ratio. RESULTS: Clinical features and radiographic atlanto-occipital joint parameters were compared between 19 patients in the PFD+OCF cohort and 38 patients in the PFD-only cohort. Demographic data were not significantly different between cohorts (p > 0.05). The mean AOJAA was significantly higher in the PFD+OCF group than in the PFD group (144° ± 12° vs 127° ± 6°, p < 0.0001). In the PFD+OCF group, atlas assimilation and atlas arch anomalies were identified in 10 (53%) and 5 (26%) patients, respectively. These anomalies were absent (n = 0) in the PFD group (p < 0.001). Multivariate regression analysis identified the following 3 CVJ radiographic variables that were predictive of OCF occurrence after PFD: AOJAA ≥ 130° (p = 0.01), clivoaxial angle < 125° (p = 0.02), and occipital condyle-C2 sagittal vertical alignment (C-C2SVA) ≥ 5 mm (p = 0.01). A predictive model based on these 3 factors accurately predicted OCF following PFD (C-statistic 0.95). CONCLUSIONS: The authors' results indicate that the occipital condyle-atlas joint complex might affect the biomechanical integrity of the CVJ in children with CM-I and syringomyelia. They describe the role of the AOJAA metric as an independent predictive factor for occurrence of OCF following PFD. Preoperative identification of these skeletal abnormalities may be used to guide surgical planning and treatment of patients with complex CM-I and coexistent osseous pathology.

Folate and epigenetic mechanisms in neural tube development and defects.

INTRODUCTION: Multiple genetic and epigenetic factors involved in central nervous system (CNS) development influence the incidence of neural tube defects (NTDs). DISCUSSION: The beneficial effect of periconceptional folic acid on NTD prevention denotes a vital role for the single-carbon biochemical pathway in NTD genesis. Indeed, NTDs are associated with polymorphisms in a diversity of genes that encode folate pathway enzymes. Recent evidence suggests that CNS development and function, and consequently NTDs, are also associated with epigenetic mechanisms, many of which participate in the folate cycle and its input and output pathways. We provide an overview with select examples drawn from the authors' research.

Extensive sinovenous thrombosis and hemorrhagic infarction during therapy for T-cell acute lymphoblastic leukemia.

Sinovenous thrombosis (SVT) is a well-recognized and serious complication in children treated for acute leukemia. This frequently occurs during or immediately upon completion of induction therapy and is commonly attributed to asparaginase therapy.Headache is the first and most common clinical symptom to occur during the early development of SVT. With advancement of the thrombosis, the clinical symptoms can progress to increased sleepiness, focal neurological deficit, seizures, and altered consciousness. We report the case of a 4-year-old girl who presented after several days of headaches and anorexia, which then progressed to seizures, left-sided weakness, and altered consciousness. She was later found to have a widespread and occlusive SVT with right cerebral hemorrhagic infarction. This case is notable for the extensive nature of the cerebral SVT and the child's complete clinical recovery from the neurological event. The report discusses the relation of the thrombosis and leukemia and also emphasizes the importance of early recognition and prompt management, while incorporating a collaborative multidisciplinary approach to prevent long-term consequences.

The Nomenclature of Chiari Malformations.

The current nomenclature of Chiari malformations includes the standard designations, Chiari 1-4, which were described by Hans Chiari in the late nineteenth century, and more recent additions, Chiari 0, 0.5, and 1.5, which emerged when the standard nomenclature failed to include important anatomical variations. The authors describe these entities and propose that to best optimize clinical care and research, it would be wise to place less focus on the eponyms and more effort on developing a descriptive or pathophysiological nomenclature.

Transgenerational epigenetic inheritance of axonal regeneration after spinal cord injury.

Human epidemiological studies reveal that dietary and environmental alterations influence the health of the offspring and that the effect is not limited to the F1 or F2 generations. Non-Mendelian transgenerational inheritance of traits in response to environmental stimuli has been confirmed in non-mammalian organisms including plants and worms and are shown to be epigenetically mediated. However, transgenerational inheritance beyond the F2 generation remains controversial in mammals. Our lab previously discovered that the treatment of rodents (rats and mice) with folic acid significantly enhances the regeneration of injured axons following spinal cord injury in vivo and in vitro, and the effect is mediated by DNA methylation. The potential heritability of DNA methylation prompted us to investigate the following question: Is the enhanced axonal regeneration phenotype inherited transgenerationally without exposure to folic acid supplementation in the intervening generations? In the present review, we condense our findings showing that a beneficial trait (i.e., enhanced axonal regeneration after spinal cord injury) and accompanying molecular alterations (i.e., DNA methylation), triggered by an environmental exposure (i.e., folic acid supplementation) to F0 animals only, are inherited transgenerationally and beyond the F3 generation.

Purified regenerating retinal neurons reveal regulatory role of DNA methylation-mediated Na+/K+-ATPase in murine axon regeneration.

While embryonic mammalian central nervous system (CNS) axons readily grow and differentiate, only a minority of fully differentiated mature CNS neurons are able to regenerate injured axons, leading to stunted functional recovery after injury and disease. To delineate DNA methylation changes specifically associated with axon regeneration, we used a Fluorescent-Activated Cell Sorting (FACS)-based methodology in a rat optic nerve transection model to segregate the injured retinal ganglion cells (RGCs) into regenerating and non-regenerating cell populations. Whole-genome DNA methylation profiling of these purified neurons revealed genes and pathways linked to mammalian RGC regeneration. Moreover, whole-methylome sequencing of purified uninjured adult and embryonic RGCs identified embryonic molecular profiles reactivated after injury in mature neurons, and others that correlate specifically with embryonic or adult axon growth, but not both. The results highlight the contribution to both embryonic growth and adult axon regeneration of subunits encoding the Na+/K+-ATPase. In turn, both biochemical and genetic inhibition of the Na+/K+-ATPase pump significantly reduced RGC axon regeneration. These data provide critical molecular insights into mammalian CNS axon regeneration, pinpoint the Na+/K+-ATPase as a key regulator of regeneration of injured mature CNS axons, and suggest that successful regeneration requires, in part, reactivation of embryonic signals.

Intraoperative neural monitoring during head and neck surgery in patients with concern for cervical spine instability.

Cervical and craniocervical instability are associated with catastrophic procedural outcomes. We discuss three individuals who required otolaryngologic surgical intervention: two with symptomatic spinal instability and one in whom spinal stability was unable to be assessed. Two cases were managed with procedural positioning precautions and evoked potential monitoring, and the other with procedural positioning precautions alone. Methods of monitoring and triggers for repositioning are discussed. This series is intended to discuss the approach and potential added value of evoked potential monitoring for risk mitigation in pediatric patients with concern for cervical spine instability.

Genetic dysregulation of an endothelial Ras signaling network in vein of Galen malformations.

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and severe congenital brain arteriovenous malformation, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP ( RASA1 ) harbored a genome-wide significant burden of loss-of-function de novo variants (p=4.79×10 -7 ). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 ( EPHB4 ) (p=1.22×10 -5 ), which cooperates with p120 RasGAP to limit Ras activation. Other probands had pathogenic variants in ACVRL1 , NOTCH1 , ITGB1 , and PTPN11 . ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomics defined developing endothelial cells as a key spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant exhibited constitutive endothelial Ras/ERK/MAPK activation and impaired hierarchical development of angiogenesis-regulated arterial-capillary-venous networks, but only when carrying a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have clinical implications.

Mutation of key signaling regulators of cerebrovascular development in vein of Galen malformations.

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and most severe of congenital brain arteriovenous malformations, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP (RASA1) harbored a genome-wide significant burden of loss-of-function de novo variants (2042.5-fold, p = 4.79 x 10-7). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 (EPHB4) (17.5-fold, p = 1.22 x 10-5), which cooperates with p120 RasGAP to regulate vascular development. Additional probands had damaging variants in ACVRL1, NOTCH1, ITGB1, and PTPN11. ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomic analysis defined developing endothelial cells as a likely spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant (Phe867Leu) exhibited disrupted developmental angiogenesis and impaired hierarchical development of arterial-capillary-venous networks, but only in the presence of a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have implications for patients and their families.

Complications and outcomes of posterior fossa decompression with duraplasty versus without duraplasty for pediatric patients with Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: The aim of this study was to determine differences in complications and outcomes between posterior fossa decompression with duraplasty (PFDD) and without duraplasty (PFD) for the treatment of pediatric Chiari malformation type I (CM1) and syringomyelia (SM). METHODS: The authors used retrospective and prospective components of the Park-Reeves Syringomyelia Research Consortium database to identify pediatric patients with CM1-SM who received PFD or PFDD and had at least 1 year of follow-up data. Preoperative, treatment, and postoperative characteristics were recorded and compared between groups. RESULTS: A total of 692 patients met the inclusion criteria for this database study. PFD was performed in 117 (16.9%) and PFDD in 575 (83.1%) patients. The mean age at surgery was 9.86 years, and the mean follow-up time was 2.73 years. There were no significant differences in presenting signs or symptoms between groups, although the preoperative syrinx size was smaller in the PFD group. The PFD group had a shorter mean operating room time (p < 0.0001), fewer patients with > 50 mL of blood loss (p = 0.04), and shorter hospital stays (p = 0.0001). There were 4 intraoperative complications, all within the PFDD group (0.7%, p > 0.99). Patients undergoing PFDD had a 6-month complication rate of 24.3%, compared with 13.7% in the PFD group (p = 0.01). There were no differences between groups for postoperative complications beyond 6 months (p = 0.33). PFD patients were more likely to require revision surgery (17.9% vs 8.3%, p = 0.002). PFDD was associated with greater improvements in headaches (89.6% vs 80.8%, p = 0.04) and back pain (86.5% vs 59.1%, p = 0.01). There were no differences between groups for improvement in neurological examination findings. PFDD was associated with greater reduction in anteroposterior syrinx size (43.7% vs 26.9%, p = 0.0001) and syrinx length (18.9% vs 5.6%, p = 0.04) compared with PFD. CONCLUSIONS: PFD was associated with reduced operative time and blood loss, shorter hospital stays, and fewer postoperative complications within 6 months. However, PFDD was associated with better symptom improvement and reduction in syrinx size and lower rates of revision decompression. The two surgeries have low intraoperative complication rates and comparable complication rates beyond 6 months.

Socioeconomic and demographic factors in the diagnosis and treatment of Chiari malformation type I and syringomyelia.

OBJECTIVE: The goal of this study was to assess the social determinants that influence access and outcomes for pediatric neurosurgical care for patients with Chiari malformation type I (CM-I) and syringomyelia (SM). METHODS: The authors used retro- and prospective components of the Park-Reeves Syringomyelia Research Consortium database to identify pediatric patients with CM-I and SM who received surgical treatment and had at least 1 year of follow-up data. Race, ethnicity, and insurance status were used as comparators for preoperative, treatment, and postoperative characteristics and outcomes. RESULTS: A total of 637 patients met inclusion criteria, and race or ethnicity data were available for 603 (94.7%) patients. A total of 463 (76.8%) were non-Hispanic White (NHW) and 140 (23.2%) were non-White. The non-White patients were older at diagnosis (p = 0.002) and were more likely to have an individualized education plan (p < 0.01). More non-White than NHW patients presented with cerebellar and cranial nerve deficits (i.e., gait ataxia [p = 0.028], nystagmus [p = 0.002], dysconjugate gaze [p = 0.03], hearing loss [p = 0.003], gait instability [p = 0.003], tremor [p = 0.021], or dysmetria [p < 0.001]). Non-White patients had higher rates of skull malformation (p = 0.004), platybasia (p = 0.002), and basilar invagination (p = 0.036). Non-White patients were more likely to be treated at low-volume centers than at high-volume centers (38.7% vs 15.2%; p < 0.01). Non-White patients were older at the time of surgery (p = 0.001) and had longer operative times (p < 0.001), higher estimated blood loss (p < 0.001), and a longer hospital stay (p = 0.04). There were no major group differences in terms of treatments performed or complications. The majority of subjects used private insurance (440, 71.5%), whereas 175 (28.5%) were using Medicaid or self-pay. Private insurance was used in 42.2% of non-White patients compared to 79.8% of NHW patients (p < 0.01). There were no major differences in presentation, treatment, or outcome between insurance groups. In multivariate modeling, non-White patients were more likely to present at an older age after controlling for sex and insurance status (p < 0.01). Non-White and male patients had a longer duration of symptoms before reaching diagnosis (p = 0.033 and 0.004, respectively). CONCLUSIONS: Socioeconomic and demographic factors appear to influence the presentation and management of patients with CM-I and SM. Race is associated with age and timing of diagnosis as well as operating room time, estimated blood loss, and length of hospital stay. This exploration of socioeconomic and demographic barriers to care will be useful in understanding how to improve access to pediatric neurosurgical care for patients with CM-I and SM.