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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.

Nanopore Sensitivity/Specificity details

Random forest model 2. A) Example decision tree from random forest model 2. B) Out-of-bag, low-grade, and high-grade tumor classification error across 500 grown decision trees. C) Image feature importance for model 2. Similar to model 1, nuclei density and TAM density are the most important predictors; however, nuclear morphology parameters and detection of anaplasia play a more important predictive role for classifying low-grade and high-grade tumors.

Accurate histopathologic diagnosis is essential for providing optimal surgical management of pediatric brain tumors. Current methods for intraoperative histology are time- and labor-intensive and often introduce artifact that limit interpretation. Stimulated Raman histology (SRH) is a novel label-free imaging technique that provides intraoperative histologic images of fresh, unprocessed surgical specimens. Here we evaluate the capacity of SRH for use in the intraoperative diagnosis of pediatric type brain tumors. SRH revealed key diagnostic features in fresh tissue specimens collected from 33 prospectively enrolled pediatric type brain tumor patients, preserving tumor cytology and histoarchitecture in all specimens. We simulated an intraoperative consultation for 25 patients with specimens imaged using both SRH and standard hematoxylin and eosin histology. SRH-based diagnoses achieved near-perfect diagnostic concordance (Cohen's kappa, κ > 0.90) and an accuracy of 92% to 96%. We then developed a quantitative histologic method using SRH images based on rapid image feature extraction. Nuclear density, tumor-associated macrophage infiltration, and nuclear morphology parameters from 3337 SRH fields of view were used to develop and validate a decision-tree machine-learning model. Using SRH image features, our model correctly classified 25 fresh pediatric type surgical specimens into normal versus lesional tissue and low-grade versus high-grade tumors with 100% accuracy. Our results provide insight into how SRH can deliver rapid diagnostic histologic data that could inform the surgical management of pediatric brain tumors.Significance: A new imaging method simplifies diagnosis and informs decision making during pediatric brain tumor surgery. Cancer Res; 78(1); 278–89. ©2017 AACR.

Random forest model 1. A) Example decision tree from random forest model 1. B) Out-of-bag, normal tissue, and tumor tissue classification error across 500 grown decision trees. C) Image feature importance for model 1.

All supplementary data except table S3A and S3B

Descriptive statistics of patient population

Purpose:Pediatric high-grade glioma (pHGG) diagnosis portends poor prognosis and therapeutic monitoring remains difficult. Tumors release cell-free tumor DNA (cf-tDNA) into cerebrospinal fluid (CSF), allowing for potential detection of tumor-associated mutations by CSF sampling. We hypothesized that direct, electronic analysis of cf-tDNA with a handheld platform (Oxford Nanopore MinION) could quantify patient-specific CSF cf-tDNA variant allele fraction (VAF) with improved speed and limit of detection compared with established methods.Experimental Design:We performed ultra-short fragment (100–200 bp) PCR amplification of cf-tDNA for clinically actionable alterations in CSF and tumor samples from patients with pHGG (n = 12) alongside nontumor CSF (n = 6). PCR products underwent rapid amplicon-based sequencing by Oxford Nanopore Technology (Nanopore) with quantification of VAF. Additional comparison to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) was performed.Results:Nanopore demonstrated 85% sensitivity and 100% specificity in CSF samples (n = 127 replicates) with 0.1 femtomole DNA limit of detection and 12-hour results, all of which compared favorably with NGS. Multiplexed analysis provided concurrent analysis of H3.3A (H3F3A) and H3C2 (HIST1H3B) mutations in a nonbiopsied patient and results were confirmed by ddPCR. Serial CSF cf-tDNA sequencing by Nanopore demonstrated correlation of radiological response on a clinical trial, with one patient showing dramatic multi-gene molecular response that predicted long-term clinical response.Conclusions:Nanopore sequencing of ultra-short pHGG CSF cf-tDNA fragments is feasible, efficient, and sensitive with low-input samples thus overcoming many of the barriers restricting wider use of CSF cf-tDNA diagnosis and monitoring in this patient population.

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.

Hydrocephalus is a common complication of aneurysmal subarachnoid hemorrhage (aSAH) that often requires acute placement of an external ventricular drain (EVD). The current systems available for determining which patients will require long-term cerebrospinal fluid diversion remain subjective. We investigated the ventricular volume change (ΔVV) after EVD clamping as an objective predictor of shunt dependence in patients with aSAH.We performed a retrospective medical record review and image analysis of patients treated for aSAH at a single academic institution who had required EVD placement for acute hydrocephalus and had undergone 1 EVD weaning trial. Head computed tomography (CT) scans obtained before and after EVD clamping were analyzed using a custom semiautomated MATLAB program (MathWorks, Natick, Massachusetts, USA), which segments each CT scan into 5 tissue types using k-means clustering. Differences in the pre- and postclamp ventricular volumes were calculated.A total of 34 patients with an indwelling shunt met the inclusion criteria and were sex- and age-matched to 34 controls without a shunt. The mean ΔVV was 19.8 mL in the shunt patients and 3.8 mL in the nonshunt patients (P 0.0001). The area under the receiver operating characteristic curve was 0.84. The optimal ΔVV threshold was 11.4 mL, with a sensitivity of 76.5% and specificity of 88.2% for predicting shunt dependence. The mean ΔVV was significantly greater for the patients readmitted for shunt placement compared with the patients not requiring cerebrospinal fluid diversion (18.69 mL vs. 3.84 mL; P = 0.005). Finally, 70% of the patients with delayed shunt dependence had ΔVV greater than the identified threshold.The ΔVV volume between head CT scans taken before and after EVD clamping was predictive of early and delayed shunt dependence.

Chiari I malformation is a common condition seen by adult and pediatric neurosurgeons. With increased utilization of MRI over time, incidental findings of Chiari I malformation are occurring more frequently. The prevalence of symptomatic Chiari I malformation is much smaller than that of asymptomatic Chiari I malformation. The prevalence of Chiari I malformation-associated syringomyelia is likely overestimated in the literature. The epidemiology of Chiari I malformation and associated syringomyelia differs based on age, sex, ethnicity, race, and socioeconomic status. The natural history of Chiari I malformation and associated syringomyelia appears to be quite benign as few patients who are managed nonsurgically later require surgical intervention.

OBJECTIVE Posterior fossa decompression with duraplasty (PFDD) is commonly performed for Chiari I malformation (CM-I) with syringomyelia (SM). However, complication rates associated with various dural graft types are not well established. The objective of this study was to elucidate complication rates within 6 months of surgery among autograft and commonly used nonautologous grafts for pediatric patients who underwent PFDD for CM-I/SM. METHODS The Park-Reeves Syringomyelia Research Consortium database was queried for pediatric patients who had undergone PFDD for CM-I with SM. All patients had tonsillar ectopia ≥ 5 mm, syrinx diameter ≥ 3 mm, and ≥ 6 months of postoperative follow-up after PFDD. Complications (e.g., pseudomeningocele, CSF leak, meningitis, and hydrocephalus) and postoperative changes in syrinx size, headaches, and neck pain were compared for autograft versus nonautologous graft. RESULTS A total of 781 PFDD cases were analyzed (359 autograft, 422 nonautologous graft). Nonautologous grafts included bovine pericardium (n = 63), bovine collagen (n = 225), synthetic (n = 99), and human cadaveric allograft (n = 35). Autograft (103/359, 28.7%) had a similar overall complication rate compared to nonautologous graft (143/422, 33.9%) (p = 0.12). However, nonautologous graft was associated with significantly higher rates of pseudomeningocele (p = 0.04) and meningitis (p < 0.001). The higher rate of meningitis was influenced particularly by the higher rate of chemical meningitis (p = 0.002) versus infectious meningitis (p = 0.132). Among 4 types of nonautologous grafts, there were differences in complication rates (p = 0.02), including chemical meningitis (p = 0.01) and postoperative nausea/vomiting (p = 0.03). Allograft demonstrated the lowest complication rates overall (14.3%) and yielded significantly fewer complications compared to bovine collagen (p = 0.02) and synthetic (p = 0.003) grafts. Synthetic graft yielded higher complication rates than autograft (p = 0.01). Autograft and nonautologous graft resulted in equal improvements in syrinx size (p < 0.0001). No differences were found for postoperative changes in headaches or neck pain. CONCLUSIONS In the largest multicenter cohort to date, complication rates for dural autograft and nonautologous graft are similar after PFDD for CM-I/SM, although nonautologous graft results in higher rates of pseudomeningocele and meningitis. Rates of meningitis differ among nonautologous graft types. Autograft and nonautologous graft are equivalent for reducing syrinx size, headaches, and neck pain.

BACKGROUND Intracranial arachnoid cysts are common incidental imaging findings. They may rarely rupture, leading to the development of subdural hygromas and high intracranial pressure (ICP). Neurosurgical intervention has been advocated in the past, but recent evidence indicates that most cases resolve spontaneously. The role of neuro-ophthalmologic monitoring in identifying the few cases that have persisting vision-threatening papilledema that justifies intervention has not been emphasized. METHODS Retrospective review of 4 cases of leaking arachnoid cysts drawn from the files of the University of Michigan Medical Center (Michigan Medicine) between 2007 and 2018. RESULTS In 1 case, surgery was avoidable as papilledema resolved over time despite lingering imaging features of mass effect. In 3 cases, papilledema persisted with the threat of permanent vision loss, prompting neurosurgical intervention. In one of those cases, the fluid collection was thinly but extensively spread across both hemispheres without brain shift; yet, papilledema was pronounced. Emergent evacuation led to rapid resolution of papilledema and encephalopathy, but with residual optic nerve damage. CONCLUSIONS Because constitutional symptoms and even imaging are not always reliable indicators of high ICP in leaking arachnoid cysts, neuro-ophthalmologic monitoring of papilledema is valuable in identifying the cases when neurosurgical intervention is necessary.

BACKGROUND: Occipital-cervical fusion (OCF) and ventral decompression (VD) may be used in the treatment of pediatric Chiari-1 malformation (CM-1) with syringomyelia (SM) as adjuncts to posterior fossa decompression (PFD) for complex craniovertebral junction pathology. OBJECTIVE: To examine factors influencing the use of OCF and OCF/VD in a multicenter cohort of pediatric CM-1 and SM subjects treated with PFD. METHODS: The Park-Reeves Syringomyelia Research Consortium registry was used to examine 637 subjects with cerebellar tonsillar ectopia ≥ 5 mm, syrinx diameter ≥ 3 mm, and at least 1 yr of follow-up after their index PFD. Comparisons were made between subjects who received PFD alone and those with PFD + OCF or PFD + OCF/VD. RESULTS: All 637 patients underwent PFD, 505 (79.2%) with and 132 (20.8%) without duraplasty. A total of 12 subjects went on to have OCF at some point in their management (PFD + OCF), whereas 4 had OCF and VD (PFD + OCF/VD). Of those with complete data, a history of platybasia (3/10, P = .011), Klippel-Feil (2/10, P = .015), and basilar invagination (3/12, P

Purpose: Pediatric high-grade glioma (pHGG) diagnosis portends poor prognosis and therapeutic monitoring remains difficult. Tumors release cell-free tumor DNA (cf-tDNA) into cerebrospinal fluid (CSF), allowing for potential detection of tumor-associated mutations by CSF sampling. We hypothesized that direct, electronic analysis of cf-tDNA with a handheld platform (Oxford Nanopore MinION) could quantify patient-specific CSF cf-tDNA variant allele fraction (VAF) with improved speed and limit of detection compared with established methods. Experimental Design: We performed ultra-short fragment (100–200 bp) PCR amplification of cf-tDNA for clinically actionable alterations in CSF and tumor samples from patients with pHGG (n = 12) alongside nontumor CSF (n = 6). PCR products underwent rapid amplicon-based sequencing by Oxford Nanopore Technology (Nanopore) with quantification of VAF. Additional comparison to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) was performed. Results: Nanopore demonstrated 85% sensitivity and 100% specificity in CSF samples (n = 127 replicates) with 0.1 femtomole DNA limit of detection and 12-hour results, all of which compared favorably with NGS. Multiplexed analysis provided concurrent analysis of H3.3A (H3F3A) and H3C2 (HIST1H3B) mutations in a nonbiopsied patient and results were confirmed by ddPCR. Serial CSF cf-tDNA sequencing by Nanopore demonstrated correlation of radiological response on a clinical trial, with one patient showing dramatic multi-gene molecular response that predicted long-term clinical response. Conclusions: Nanopore sequencing of ultra-short pHGG CSF cf-tDNA fragments is feasible, efficient, and sensitive with low-input samples thus overcoming many of the barriers restricting wider use of CSF cf-tDNA diagnosis and monitoring in this patient population.

OBJECTIVENormal percentile growth charts for head circumference, length, and weight are well-established tools for clinicians to detect abnormal growth patterns. Currently, no standard exists for evaluating normal size or growth of cerebral ventricular volume. The current standard practice relies on clinical experience for a subjective assessment of cerebral ventricular size to determine whether a patient is outside the normal volume range. An improved definition of normal ventricular volumes would facilitate a more data-driven diagnostic process. The authors sought to develop a growth curve of cerebral ventricular volumes using a large number of normal pediatric brain MR images.METHODSThe authors performed a retrospective analysis of patients aged 0 to 18 years, who were evaluated at their institution between 2009 and 2016 with brain MRI performed for headaches, convulsions, or head injury. Patients were excluded for diagnoses of hydrocephalus, congenital brain malformations, intracranial hemorrhage, meningitis, or intracranial mass lesions established at any time during a 3- to 10-year follow-up. The volume of the cerebral ventricles for each T2-weighted MRI sequence was calculated with a custom semiautomated segmentation program written in MATLAB. Normal percentile curves were calculated using the lambda-mu-sigma smoothing method.RESULTSVentricular volume was calculated for 687 normal brain MR images obtained in 617 different patients. A chart with standardized growth curves was developed from this set of normal ventricular volumes representing the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. The charted data were binned by age at scan date by 3-month intervals for ages 0–1 year, 6-month intervals for ages 1–3 years, and 12-month intervals for ages 3–18 years. Additional percentile values were calculated for boys only and girls only.CONCLUSIONSThe authors developed centile estimation growth charts of normal 3D ventricular volumes measured on brain MRI for pediatric patients. These charts may serve as a quantitative clinical reference to help discern normal variance from pathologic ventriculomegaly.

OBJECTIVEPediatric neurosurgery is a core component of neurosurgical residency training. Pediatric case minimums are established by the Neurosurgery Residency Review Committee of the Accreditation Council for Graduate Medical Education (ACGME). Case minimums, by themselves, allow for great variability in training between programs. There are no prior data on how the residency programs meet these requirements. The authors’ objective was to gather information on pediatric neurosurgical education among the ACGME-accredited neurosurgery training programs in order to shape further pediatric neurosurgical educational efforts.METHODSA 25-question survey about pediatric neurosurgical education was created by the Education Committee of the Section on Pediatric Neurological Surgery of the American Association of Neurological Surgeons/Congress of Neurological Surgeons and distributed to program directors of all 111 ACGME-accredited neurosurgery training programs.RESULTSThe response rate was 77% (86/111). In 55% of programs the residents are rotated to a responder-designated “freestanding” children’s hospital, and 39% of programs rotate residents to a children’s hospital within a larger adult hospital or a general hospital. There are 4 or fewer pediatric neurosurgical faculty in 91% of programs. In 12% of programs less than 100 cases are performed per year, and in 45% more than 500 are performed. In 31% of responding neurosurgery residency programs there is also a pediatric neurosurgery fellowship program supported by the same sponsoring institution. Seventy-seven percent of programs have at least one specific pediatric neurosurgery rotation, with 71% of those rotations occurring during postgraduate year 3 and 50% occurring during postgraduate year 4. The duration of pediatric rotation varies from no specific rotation to more than 1 year, with 48% of residents spending 4–6 months on a pediatric rotation and 12% spending 7–11 months. Last, 17% of programs send their residents to external sites sponsoring other residency programs for their pediatric rotation.CONCLUSIONSThere is great variety between neurosurgery training programs with regard to resident education in pediatric neurosurgery. This study’s data will serve as a baseline for future studies, and the authors hope the findings will guide further efforts in pediatric neurosurgical education in residency training programs.

Background Feedback is a major component of any educational process. Competency assessment and feedback are essential tools for teaching surgical skills. Most current systems of assessment within neurosurgical residency programs use evaluations aggregated over a period of time, which lead to significant bias, rather than case-specific feedback. We describe the use of a mobile device application called SIMPL (System for Improving and Measuring Procedural Learning) to allow for immediate surgical competency assessment and improve the quality of feedback after every operative experience. Methods We retrospectively assessed our use of this program and neurosurgery residents' response to the program. Institutional review board approval was not required, and no patients were involved in the study. This application has already been implemented within general surgery programs with promising results. We document its implementation in a neurosurgery program and the output of the program for residents and program directors. Results This is the first documentation of such an application within a neurosurgical residency program. In a 6-month period at a single institution, around 300 evaluations were completed by residents and faculty, with a >80% response rate within both groups. Furthermore, these evaluations were companied by a 60% dictation rate from faculty, which contains verbal feedback that is available to residents for playback at any time. Conclusions The telephone-based SIMPL application allows for assessment of surgical competency and remains quick and easy to use, giving it the potential to improve individual neurosurgical training experiences across the United States.

OBJECTIVEFactors associated with syrinx size in pediatric patients undergoing posterior fossa decompression (PFD) or PFD with duraplasty (PFDD) for Chiari malformation type I (CM-I) with syringomyelia (SM; CM-I+SM) are not well established.METHODSUsing the Park-Reeves Syringomyelia Research Consortium registry, the authors analyzed variables associated with syrinx radiological outcomes in patients (< 20 years old at the time of surgery) with CM-I+SM undergoing PFD or PFDD. Syrinx resolution was defined as an anteroposterior (AP) diameter of ≤ 2 mm or ≤ 3 mm or a reduction in AP diameter of ≥ 50%. Syrinx regression or progression was defined using 1) change in syrinx AP diameter (≥ 1 mm), or 2) change in syrinx length (craniocaudal, ≥ 1 vertebral level). Syrinx stability was defined as a < 1-mm change in syrinx AP diameter and no change in syrinx length.RESULTSThe authors identified 380 patients with CM-I+SM who underwent PFD or PFDD. Cox proportional hazards modeling revealed younger age at surgery and PFDD as being independently associated with syrinx resolution, defined as a ≤ 2-mm or ≤ 3-mm AP diameter or ≥ 50% reduction in AP diameter. Radiological syrinx resolution was associated with improvement in headache (p < 0.005) and neck pain (p < 0.011) after PFD or PFDD. Next, PFDD (p = 0.005), scoliosis (p = 0.007), and syrinx location across multiple spinal segments (p = 0.001) were associated with syrinx diameter regression, whereas increased preoperative frontal-occipital horn ratio (FOHR; p = 0.007) and syrinx location spanning multiple spinal segments (p = 0.04) were associated with syrinx length regression. Scoliosis (HR 0.38 [95% CI 0.16–0.91], p = 0.03) and smaller syrinx diameter (5.82 ± 3.38 vs 7.86 ± 3.05 mm; HR 0.60 [95% CI 0.34–1.03], p = 0.002) were associated with syrinx diameter stability, whereas shorter preoperative syrinx length (5.75 ± 4.01 vs 9.65 ± 4.31 levels; HR 0.21 [95% CI 0.12–0.38], p = 0.0001) and smaller pB-C2 distance (6.86 ± 1.27 vs 7.18 ± 1.38 mm; HR 1.44 [95% CI 1.02–2.05], p = 0.04) were associated with syrinx length stability. Finally, younger age at surgery (8.19 ± 5.02 vs 10.29 ± 4.25 years; HR 1.89 [95% CI 1.31–3.04], p = 0.01) was associated with syrinx diameter progression, whereas increased postoperative syrinx diameter (6.73 ± 3.64 vs 3.97 ± 3.07 mm; HR 3.10 [95% CI 1.67–5.76], p = 0.003), was associated with syrinx length progression. PFD versus PFDD was not associated with syrinx progression or reoperation rate.CONCLUSIONSThese data suggest that PFDD and age are independently associated with radiological syrinx improvement, although forthcoming results from the PFDD versus PFD randomized controlled trial (NCT02669836, clinicaltrials.gov) will best answer this question.

OBJECTIVEThe nature of the relationship between spinal cord syrinx and tethered cord is not well known. It is unclear if surgical cord untethering results in resolution or improvement of an associated syrinx. The objective of this study was to report the response of spinal cord syrinx to surgical cord untethering.METHODSThe authors retrospectively reviewed all patients with a syrinx and tethered cord who presented to a single institution over an 11-year interval. Patients with open neural tube defects were excluded. Thirty-one patients were identified, 25 of whom had both clinical and imaging follow-up after surgery. Patients were grouped according to etiology of the tethered cord. Clinical outcomes and syrinx characteristics were recorded.RESULTSOf the 25 patients with tethered cord, 68% (n = 17) were male. The average age at presentation was 2.5 years (0–10.1 years) and age at surgery was 3.7 years (range 1 day to 17 years). Etiologies of tethered cord were lipomyelomeningocele (n = 8), thickened/fatty filum (n = 7), intradural lipoma (n = 5), myelocystocele (n = 2), meningocele (n = 2), and diastematomyelia (n = 1). Twenty-three of the patients underwent primary untethering, whereas 2 patients had received untethering previously at another institution. The average syrinx length and width prior to surgery were 4.81 vertebral levels (SD 4.35) and 5.19 mm (SD 2.55 mm), respectively. Conus level ranged from L1 to S3. Patients were followed for an average of 8.4 years (1.35–15.85 years). Overall there was no significant change in syrinx length or width postoperatively; the average syrinx length increased by 0.86 vertebral levels (SD 4.36) and width decreased by 0.72 mm (SD 2.94 mm). Seven of 25 patients had improvement in at least one presenting symptom, including scoliosis, weakness, bowel/bladder dysfunction, and pain. Eight patients had stable presenting symptoms. Six patients were asymptomatic and 5 patients had new or worsening symptoms, which included scoliosis, pain, or sensory changes.CONCLUSIONSAlthough some syrinxes improved after surgery for tethered cord, radiological improvement was not consistent and did not appear to be associated with change in clinical symptoms. The decision to surgically untether a cord should be focused on the clinical symptoms and not the presence of a syrinx alone. Further studies are needed to confirm this finding.

OBJECTIVEThickened or fatty filum terminale is an occult lesion that can cause tethered cord syndrome requiring surgical untethering. This study’s objectives were to estimate the incidence of tethered fibrofatty filum terminale (TFFT) in a large insured pediatric population, identify predictors of surgery among those TFFT patients, and assess a diagnostic algorithm.METHODSTFFT was defined according to the ICD-9-CM code for cord tethering (742.59), after excluding codes for diastematomyelia, lipomyelomeningocele, terminal myelocystocele, meningocele, and myelomeningocele. Utilizing the Optum Insight database for 2001–2014, the authors identified pediatric patients (< 21 years) in the US who were diagnosed with a tethered cord and estimated the TFFT incidence rates in that source population and the surgical untethering probability among TFFT patients over the 14-year period. Logistic regression was used to estimate the effects (adjusted OR and 95% CI) of age at diagnosis, sex, Charlson Comorbidity Index (CCI) score, diagnosis of Chiari malformation type I, diagnosis of syrinx, and the probability of surgery by US census region. Lastly, to evaluate their algorithm for identifying TFFT from ICD-9 codes, the authors estimated its positive predictive value (PPV) among 50 children who were diagnosed at their institution and met the ICD-9-CM criteria.RESULTSThere were 3218 diagnoses of TFFT, with 482 of these pediatric patients undergoing tethered cord release during the study period. The estimated incidence rate was 12.0 per 100,000/year (95% CI 11.6–12.4 per 100,000/year). The incidence rate was slightly higher in females than in males (12.7 vs 11.4 per 100,000/year). The probability of surgery in the total pediatric TFFT population was 15.0% (95% CI 13.8%–16.2%) and was greater in children with a syrinx (OR 2.2, 95% CI 1.6–3.0), children 7–11 years of age at diagnosis versus < 1 year (OR 1.5, 95% CI 1.1–2.0), CCI score ≥ 3 versus 0 (OR 2.3, 95% CI 1.4–3.8), and residents of the Western vs Northeastern US (OR 2.3, 95% CI 1.6–3.5). In the authors’ own institution’s database, the PPV of TFFT was 35/50 (70.0%, 95% CI 57.3%–82.7%) for identifying tethered cord due to fibrofatty filum terminale among childhood positives.CONCLUSIONSPatients with comorbidities or an associated syrinx showed a higher risk of untethering procedures for TFFT. Also, surgery was appreciably more frequent in the Western US. These findings signify the need for a collaborative prospective cohort study of long-term outcomes for TFFT patients with and without surgery to determine which patients should have surgery.

Intraoperative diagnosis is essential for providing safe and effective care during cancer surgery1. The existing workflow for intraoperative diagnosis based on hematoxylin and eosin staining of processed tissue is time, resource and labor intensive2,3. Moreover, interpretation of intraoperative histologic images is dependent on a contracting, unevenly distributed, pathology workforce4. In the present study, we report a parallel workflow that combines stimulated Raman histology (SRH)5-7, a label-free optical imaging method and deep convolutional neural networks (CNNs) to predict diagnosis at the bedside in near real-time in an automated fashion. Specifically, our CNNs, trained on over 2.5 million SRH images, predict brain tumor diagnosis in the operating room in under 150 s, an order of magnitude faster than conventional techniques (for example, 20-30 min)2. In a multicenter, prospective clinical trial (n = 278), we demonstrated that CNN-based diagnosis of SRH images was noninferior to pathologist-based interpretation of conventional histologic images (overall accuracy, 94.6% versus 93.9%). Our CNNs learned a hierarchy of recognizable histologic feature representations to classify the major histopathologic classes of brain tumors. In addition, we implemented a semantic segmentation method to identify tumor-infiltrated diagnostic regions within SRH images. These results demonstrate how intraoperative cancer diagnosis can be streamlined, creating a complementary pathway for tissue diagnosis that is independent of a traditional pathology laboratory.

OBJECTIVE Benign expansion of the subarachnoid spaces (BESS) is a condition seen in macrocephalic infants. BESS is associated with mild developmental delays which tend to resolve within a few years. It is accepted that patients with BESS are at increased risk of spontaneous subdural hematomas (SDHs), although the exact pathophysiology is not well understood. The prevalence of spontaneous SDH in BESS patients is poorly defined, with only a few large single-center series published. In this study the authors aimed to better define BESS prevalence and developmental outcomes through the longitudinal review of a large cohort of BESS patients. METHODS A large retrospective review was performed at a single institution from 1995 to 2020 for patients 2 years of age or younger with a diagnosis of BESS by neurology or neurosurgery and head circumference > 85th percentile. Demographic data, head circumference, presence of developmental delay, occurrence of SDH, and need for surgery were extracted from patient charts. The subarachnoid space (SAS) size was measured from the available MR images, and the sizes of those who did and did not develop SDH were compared. RESULTS Free text search revealed BESS mentioned within the medical records of 1410 of 2.6 million patients. After exclusion criteria, 480 patients remained eligible for the study. Thirty-two percent (n = 154) of patients were diagnosed with developmental delay, most commonly gross motor delay (53%). Gross motor delay resolved in 86% of patients at a mean age of 22.2 months. The prevalence of spontaneous SDH in this BESS population over a period of 25 years was 8.1%. There was no significant association between SAS size and SDH formation. CONCLUSIONS This study represents results for one of the largest cohorts of patients with BESS at a single institution. Gross motor delay was the most common developmental delay diagnosed, and a majority of patients had resolution of their delay. These data support that children with BESS have a higher prevalence of SDH than the general pediatric population, although SAS size was not significantly associated with SDH development.

With increasing use of intracranial imaging, the diagnosis of benign intracranial cysts is becoming more frequent in the pediatric population. These lesions are usually incidentally discovered during the work-up of unrelated symptoms. Most do not require treatment and many do not even require imaging follow-up. When symptomatic, symptoms of these lesions are usually caused by local mass effect. Symptomatic lesions warrant neurosurgical evaluation, and may require surgical intervention in rare, well-selected cases. This article describes three common benign intracranial cysts found in the pediatric population: arachnoid cysts, choroid cysts, and pineal cysts.

Background Cerebrospinal fluid (CSF) velocity at the craniovertebral junction (CVJ) is known to be altered in patients with Chiari I malformation (CMI), and normalization of CSF velocities is associated with symptom resolution. However, preoperative and intraoperative prediction methods have thus far failed to identify patients in whom CSF velocities can be normalized with posterior fossa decompression (PFD) without duraplasty. Phase contrast MRI (PC-MRI) may assist not only in diagnosis of CMI but also in guiding the intraoperative decision to perform duraplasty during PFD. Purpose To use intraoperative MRI data to quantify changes in CSF hydrodynamics at the CVJ during each step of PFD with duraplasty (PFDD) in 12 consecutive patients. Study type Retrospective case series with all patients imaged before, during and after decompression, and all data analyzed postprocedure. Population/subjects Pediatric patients, mean age 14 years (range 4-18), undergoing PFD for CMI. Field strength/sequence Intraoperative studies involved a dedicated 1.5T Siemens MRI imager. PC-MRI scans were in the axial plane at the CVJ. Assessment Two observers assessed measurements. Statistical test The equality of matched pairs of observations was tested using the Wilcoxon matched-pairs signed-ranks test. Results Data analyses of the PC-MRI demonstrated a marked and immediate increase in CSF velocity at the posterior CVJ during PFDD. Mean cranially-directed velocities increased by a mean of 1.049cm/s (P = 0.028) from preincision to postoperative measurement. There was a mean 0.45 cm/s (P = 0.022) increase in mean cranial velocity from preincision to bone decompression scans, and a mean 0.48 cm/s (P = 0.018) increase in mean velocity from preincision to duraplasty. Data conclusion In all subjects, significant increases in the mean and peak velocities of cranially- and caudally-directed velocities were observed from preincision to post-PFDD scans at the posterior CVJ. Level of evidence 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:1463-1470.

Background A range of opinions exist in the literature regarding obstetric management of pregnant women with Chiari malformation type I (CM-I). Objective To examine obstetrical practices and outcomes with childbirth of women with CM-I. Methods We examined insurance claims data from a large, privately insured health care network and identified admissions for childbirth from 2004 to 2014. Women with a diagnosis of CM-I as well as normal controls were analyzed for demographic characteristics, type of obstetric management, and complications of childbirth. Results We identified 866 patients with CM-I diagnosis who had 1048 hospitalizations for delivery, including 103 deliveries to 83 patients who underwent performance of CM-I decompression (CMD) either before or after childbirth. Among 400 births that occurred after CM-I diagnosis, rates of caesarean section (C-section) were higher (42.3% vs 36.2%, OR 1.29, 95% CI 1.00-1.66, P = .05) and rates of epidural analgesia were lower (45.3% vs 55.4%, OR 0.67, 95% CI 0.52-0.85, P = .001) compared to 648 births before CM-I diagnosis. The rate of serious maternal morbidity was similar among deliveries to women with CM-I diagnosis (both before and after delivery) compared to 11 000 normal controls. Conclusion A diagnosis of CM-I prior to delivery is associated with a higher rate of C-section and a lower rate of epidural analgesia. Rates of serious maternal morbidity among women with CM-I were similar to those for normal controls. The data suggest a predelivery diagnosis of CM-I may influence obstetric decisions despite no evidence of substantially increased delivery risk in this group.

OBJECTIVEThe goal of this study was to determine the rates of screening and surgery for foramen magnum stenosis in children with achondroplasia in a large, privately insured healthcare network.METHODSRates of screening and surgery for foramen magnum stenosis in children with achondroplasia were determined using de-identified insurance claims data from a large, privately insured healthcare network of over 58 million beneficiaries across the United States between 2001 and 2014. Cases of achondroplasia and screening and surgery claims were identified using a combination of International Classification of Diseases diagnosis codes and Current Procedural Terminology codes. American Academy of Pediatrics (AAP) practice guidelines were used to determine screening trends.RESULTSThe search yielded 3577 children age 19 years or younger with achondroplasia. Of them, 236 met criteria for inclusion in the screening analysis. Among the screening cohort, 41.9% received some form of screening for foramen magnum stenosis, whereas 13.9% of patients were fully and appropriately screened according to the 2005 guidelines from the AAP. The screening rate significantly increased after the issuance of the AAP guidelines. Among all children in the cohort, 25 underwent cervicomedullary decompression for foramen magnum stenosis. The incidence rate of undergoing cervicomedullary decompression was highest in infancy (28 per 1000 patient-years) and decreased with age (5 per 1000 patient-years for all other ages combined).CONCLUSIONSChildren with achondroplasia continue to be underscreened for foramen magnum stenosis, although screening rates have improved since the release of the 2005 AAP surveillance guidelines. The incidence of surgery was highest in infants and decreased with age.

BACKGROUND Clinical findings in children with unilateral coronal craniosynostosis are characteristic, and therefore clinicians have questioned the need for confirmatory imaging. Preoperative computed tomographic imaging is a powerful tool for diagnosing associated anomalies that can alter treatment management and surgical planning. The authors' aim was to determine whether and how routine preoperative imaging affected treatment management in unilateral coronal craniosynostosis patients within their institution. METHODS A retrospective, single-center review of all patients who underwent cranial vault remodeling for unilateral coronal craniosynostosis between 2006 and 2014 was performed. Patient data included demographics, age at computed tomographic scan, age at surgery, results of the radiographic evaluation, and modification of treatment following radiologic examination. RESULTS Of 194 patients diagnosed with single-suture craniosynostosis, 29 were diagnosed with unilateral coronal craniosynostosis. Additional radiographic anomalies were found in 19 unilateral coronal craniosynostosis patients (65.5 percent). These included severe deviation of the anterior superior sagittal sinus [n = 12 (41.4 percent)], Chiari I malformation [n = 1 (3.4 percent)], and benign external hydrocephalus [n = 2 (6.9 percent)]. The radiographic anomalies resulted in a change in management for 48.3 percent of patients. Specifically, alteration in frontal craniotomy design occurred in 12 patients (41.4 percent), and two patients (6.9 percent) required further radiographic studies. CONCLUSIONS Although clinical findings in children with unilateral coronal craniosynostosis are prototypical, preoperative computed tomographic imaging is still of great consequence and continues to play an important role in surgical management. Preoperative imaging enabled surgeons to alter surgical management and avoid inadvertent complications such as damage to a deviated superior sagittal sinus. Imaging findings of Chiari malformation and hydrocephalus also permitted judicious follow-up. CLINICAL QUESTIONS/LEVEL OF EVIDENCE Therapeutic, IV.

Background Prophylactic antiepileptic drugs (pAEDs) are often prescribed for seizure prophylaxis in patients undergoing surgical treatment of unruptured intracranial aneurysms (UIAs). We aimed to evaluate the benefit of pAEDs in patients undergoing surgical repair of UIAs. Methods We randomly assigned eligible patients undergoing surgical repair of UIAs to receive levetiracetam for seven days post-operatively or standard care alone. The primary outcome was the evaluation of seizures in the perioperative period (within 4 weeks). We also evaluated seizure occurrence throughout follow-up and assessed functional outcomes using the modified Rankin scale score (mRS). Results 35 patients were randomized to the “no-levetiracetam” group and 41 patients were randomized to receive levetiracetam. The two study groups had similar overall baseline characteristics and the surgical complication rate was similar for both groups (p = 0.8). One patient in the “no-levetiracetam” group had a seizure in the perioperative period versus 2 patients in the group randomized to receive levetiracetam (2.9% vs 4.9%, respectively, p = 1.00). No patients in the “no-levetiracetam” group had any additional late seizures (mean follow-up of 20.4 months), but three patients in the levetiracetam group had late seizures during follow-up (mean follow-up of 19.1 months) (0% vs 7.3%, p = 0.2). mRS score of 0-2 at 90 days and at the latest follow-up were similar between the two groups (p = 1.00). Conclusions Perioperative seizure prophylaxis with levetiracetam does not reduce the rate of seizures as compared to controls in patients undergoing surgical repair of UIAs.

OBJECTIVE The objective of this study was to understand the natural history of scoliosis in patients with Chiari malformation type I (CM-I) with and without syringomyelia. METHODS A retrospective review of data was conducted. Patients with CM-I were identified from a cohort of 14,118 individuals age 18 years or younger who had undergone MRI over an 11-year period at the University of Michigan. Patients eligible for study inclusion had a coronal curve ≥ 10° on radiography, associated CM-I with or without syringomyelia, and at least 1 year of clinical follow-up prior to any surgery. Curve magnitude at initial diagnosis, prior to posterior fossa decompression (PFD; if applicable), and at the last follow-up (prior to any surgical correction of scoliosis) was recorded, and clinical and radiographic characteristics were noted. The change in curve magnitude by 10° was defined as curve progression (increase by 10°) or regression (decrease by 10°). RESULTS Forty-three patients met the study inclusion criteria and were analyzed. About one-third (35%) of the patients presented with symptoms attributed to their CM-I. The mean degree of scoliosis at presentation was 32.6° ± 17.7°. Twenty-one patients (49%) had an associated syrinx. The mean tonsil position below the level of the foramen magnum was 9.8 ± 5.8 mm. Patients with a syrinx were more likely to have a curve > 20° (86% vs 41%, p = 0.002). Curve magnitude remained stable (≤ ±10°) in 77% of patients (33/43), progressed in 16% (7/43), and regressed in 7% (3/43). Mean age was higher (14.8 ± 0.59 years) among patients with regressed curves (p = 0.026). All regressed curves initially measured ≤ 20° (mean 14° ± 5.3°), and none of the patients with regressed curves had a syrinx. The change in curve magnitude was statistically similar in patients with (7.32° ± 17.7°) and without (5.32° ± 15.8°) a syrinx (p = 0.67). After a mean follow-up of 3.13 ± 2.04 years prior to surgery, 27 patients (63%) ultimately underwent posterior fossa or scoliosis correction surgery. For those who eventually underwent PFD only, the rate of change in curve magnitude prior to surgery was 0.054° ± 0.79°. The rate of change in curve magnitude was statistically similar before (0.054° ± 0.79°) and after (0.042° ± 0.33°) surgery (p = 0.45) for patients who underwent PFD surgery only. CONCLUSIONS The natural history of scoliosis in the presence of CM-I is variable, though most curves remained stable. All curves that regressed were ≤ 20° at initial diagnosis, and most patients in such cases were older at scoliosis diagnosis. Patients who underwent no surgery or PFD only had similar profiles for the change in curve magnitude, which remained relatively stable overall, as compared to patients who underwent PFD and subsequent fusion, who demonstrated curve progression. Among the patients with a syrinx, no curves regressed, most remained stable, and some progressed. Understanding this variability is a first step toward building a prediction model for outcomes for these patients.

Introduction Prophylactic antiepileptic drugs (AEDs) are often prescribed for seizure prophylaxis in patients undergoing surgical treatment of unruptured intracranial aneurysms (UIAs). We aimed to evaluate the benefit of prophylactic AEDs in patients undergoing surgical repair of UIAs. Methods We randomly assigned eligible patients undergoing surgical repair of UIAs to receive levetiracetam for seven days post-operatively or standard care alone. The primary outcome was the evaluation of seizures in the perioperative period (within 4 weeks). We also evaluated seizure occurrence throughout follow-up and assessed functional outcomes using the modified Rankin scale score (mRS). Results 35 patients were randomized to the ‘no levetiracetam’ group and 41 patients were randomized to receive levetiracetam. The two study groups had similar overall baseline characteristics and the surgical complication rate was similar for both groups (P=0.8). One patient in the ‘no levetiracetam’ group had a seizure in the perioperative period versus 2 patients in the group randomized to receive levetiracetam (2.9% vs 4.9%, respectively, P=1.00). No patients in the ‘no levetiracetam’ group had any additional late seizures (mean follow-up of 20.4 months), but three patients in the levetiracetam group had late seizures during follow-up (mean follow-up of 19.1 months) (0% vs 7.3%, P=0.2). mRS score of 0–2 at 90 days and at the latest follow-up were similar between the two groups (P=1.00). Conclusions Perioperative seizure prophylaxis with levetiracetam does not reduce the rate of seizures as compared to controls in patients undergoing surgical repair of UIAs. Disclosures B. Daou: None. K. Holste: None. G. Palmateer: None. B. Thompson: None. C. Lint: None. J. Elenbaas: None. C. Maher: None. A. Pandey: None.

OBJECTIVE Scoliosis is common in patients with Chiari malformation type I (CM-I)–associated syringomyelia. While it is known that treatment with posterior fossa decompression (PFD) may reduce the progression of scoliosis, it is unknown if decompression with duraplasty is superior to extradural decompression. METHODS A large multicenter retrospective and prospective registry of 1257 pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and syrinx (≥ 3 mm in axial width) was reviewed for patients with scoliosis who underwent PFD with or without duraplasty. RESULTS In total, 422 patients who underwent PFD had a clinical diagnosis of scoliosis. Of these patients, 346 underwent duraplasty, 51 received extradural decompression alone, and 25 were excluded because no data were available on the type of PFD. The mean clinical follow-up was 2.6 years. Overall, there was no difference in subsequent occurrence of fusion or proportion of patients with curve progression between those with and those without a duraplasty. However, after controlling for age, sex, preoperative curve magnitude, syrinx length, syrinx width, and holocord syrinx, extradural decompression was associated with curve progression > 10°, but not increased occurrence of fusion. Older age at PFD and larger preoperative curve magnitude were independently associated with subsequent occurrence of fusion. Greater syrinx reduction after PFD of either type was associated with decreased occurrence of fusion. CONCLUSIONS In patients with CM-I, syrinx, and scoliosis undergoing PFD, there was no difference in subsequent occurrence of surgical correction of scoliosis between those receiving a duraplasty and those with an extradural decompression. However, after controlling for preoperative factors including age, syrinx characteristics, and curve magnitude, patients treated with duraplasty were less likely to have curve progression than patients treated with extradural decompression. Further study is needed to evaluate the role of duraplasty in curve stabilization after PFD.

BACKGROUND AND PURPOSE: T2 signal and FLAIR changes in patients undergoing stereotactic radiosurgery for brain AVMs may occur posttreatment and could result in adverse radiation effects. We aimed to evaluate outcomes in patients with these imaging changes, the frequency and degree of this response, and factors associated with it. MATERIALS AND METHODS: Through this retrospective cohort study, consecutive patients treated with stereotactic radiosurgery for brain AVMs who had at least 1 year of follow-up MR imaging were identified. Logistic regression analysis was used to evaluate predictors of outcomes. RESULTS: One-hundred-sixty AVMs were treated in 148 patients (mean, 35.6 years of age), including 42 (26.2%) pediatric AVMs. The mean MR imaging follow-up was 56.5 months. The median Spetzler-Martin grade was III. The mean maximal AVM diameter was 2.8 cm, and the mean AVM target volume was 7.4 mL. The median radiation dose was 16.5 Gy. New T2 signal and FLAIR hyperintensity were noted in 40% of AVMs. T2 FLAIR volumes at 3, 6, 12, 18, and 24 months were, respectively, 4.04, 55.47, 56.42, 48.06, and 29.38 mL Radiation-induced neurologic symptoms were encountered in 34.4%. In patients with radiation-induced imaging changes, 69.2% had new neurologic symptoms versus 9.5% of patients with no imaging changes (P = .0001). Imaging changes were significantly associated with new neurologic findings (P

Purpose Brain tumors have become the leading cause of cancer-related mortality in young patients. Novel effective therapies on the basis of the unique biology of each tumor are urgently needed. The goal of this study was to evaluate the feasibility, utility, and clinical impact of integrative clinical sequencing and genetic counseling in children and young adults with high-risk brain tumors. Patients and Methods Fifty-two children and young adults with brain tumors designated by the treating neuro-oncologist to be high risk (> 25% chance for treatment failure; mean age, 10.2 years; range, 0 to 39 years) were enrolled in a prospective, observational, consecutive case series, in which participants underwent integrative clinical exome (tumor and germline DNA) and transcriptome (tumor RNA) sequencing and genetic counseling. Results were discussed in a multi-institutional brain tumor precision medicine teleconference. Results Sequencing revealed a potentially actionable germline or tumor alteration in 25 (63%) of 40 tumors with adequate tissue, of which 21 (53%) resulted in an impact on treatment or change of diagnosis. Platelet-derived growth factor receptor or fibroblast growth factor receptor pathway alterations were seen in nine of 20 (45%) glial tumors. Eight (20%) sequenced tumors harbored an oncogenic fusion isolated on RNA sequencing. Seventeen of 20 patients (85%) with glial tumors were found to have a potentially actionable result, which resulted in change of therapy in 14 (70%) patients. Patients with recurrent brain tumors receiving targeted therapy had a median progression-free survival (from time on therapy) of 4 months. Conclusion Selection of personalized agents for children and young adults with high-risk brain tumors on the basis of integrative clinical sequencing is feasible and resulted in a change in therapy in more than two thirds of children and young adults with high-risk glial tumors.

OBJECTIVEChiari malformation Type I (CM-I) is typically defined on imaging by a cerebellar tonsil position ≥ 5 mm below the foramen magnum. Low cerebellar tonsil position is a frequent incidental finding on brain or cervical spine imaging, even in asymptomatic individuals. Nonspecific symptoms (e.g., headache and neck pain) are common in those with low tonsil position as well as in those with normal tonsil position, leading to uncertainty regarding appropriate management for many patients with low tonsil position and nonspecific symptoms. Because cerebellar tonsil position is not strictly correlated with the presence of typical CM-I symptoms, the authors sought to determine if other 2D morphometric or 3D volumetric measurements on MRI could distinguish between patients with asymptomatic and symptomatic CM-I.METHODSThe authors retrospectively analyzed records of 102 pediatric patients whose records were in the University of Michigan clinical CM-I database. All patients in this database had cerebellar tonsil position ≥ 5 mm below the foramen magnum. Fifty-one symptomatic and 51 asymptomatic patients were matched for age at diagnosis, sex, tonsil position, and tonsil morphology. National Institutes of Health ImageJ software was used to obtain six 2D anatomical MRI measurements, and a semiautomated segmentation tool was used to obtain four 3D volumetric measurements of the posterior fossa and CSF subvolumes on MRI.RESULTSNo significant differences were observed between patients with symptomatic and asymptomatic CM-I related to tentorium length (50.3 vs 51.0 mm; p = 0.537), supraoccipital length (39.4 vs 42.6 mm; p = 0.055), clivus-tentorium distance (52.0 vs 52.1 mm; p = 0.964), clivus-torcula distance (81.5 vs 83.3 mm; p = 0.257), total posterior fossa volume (PFV; 183.4 vs 190.6 ml; p = 0.250), caudal PFV (152.5 vs 159.8 ml; p = 0.256), fourth ventricle volume to caudal PFV ratio (0.0140 vs 0.0136; p = 0.649), or CSF volume to caudal PFV ratio (0.071 vs 0.061; p = 0.138).CONCLUSIONSNo clinically useful 2D or 3D measurements were identified that could reliably distinguish pediatric patients with symptoms attributable to CM-I from those with asymptomatic CM-I.

Sacrococcygeal teratoma (SCT) with intraspinal extension is rare. There is a risk of paraplegia associated with prolonged spinal cord compression. We present the case of an infant with a prenatal diagnosis of an SCT with a large intraspinal component that was causing compression of the lower spinal cord. Ultrasound at 33 weeks showed bilateral lower extremity and foot movement without hydrops or cardiac failure. Multidisciplinary decision was made to administer betamethasone and proceed with Cesarean delivery at 34 weeks. A vigorous live-born female was delivered and a multilevel laminectomy was performed at day of life 4. The pelvic resection was performed at 4 months. Pathology revealed mature teratoma. She had an uncomplicated postoperative course, is ambulatory, continent of stool, and has no evidence of recurrence. We conclude that intraspinal extension of SCT should be evaluated prenatally with ultrasound and fetal MRI. If there is concern for spinal cord compression, early delivery and urgent decompressive laminectomy may diminish the neurologic sequelae of prolonged spinal cord compression. Since these cases are rare, risks of prematurity need to be weighed against the neurologic risks. These infants should be treated with a multidisciplinary approach.