Clinical and socioeconomic predictors of shunt malfunction in the pediatric emergency department.

OBJECTIVE: The aim of this study was to delineate the clinical and socioeconomic variables associated with shunt revision in pediatric patients presenting to the emergency department (ED) with concerns of ventricular shunt malfunction. METHODS: A retrospective analysis of pediatric ED consultations for shunt malfunction over a 1-year period was conducted, examining clinical symptoms, radiographic findings, and socioeconomic variables. Sensitivities, specificities, and positive and negative predictive values were calculated for each presenting symptom collected. Logistic regression models were used to estimate the odds ratios for shunt revision based on these variables, and multivariate analyses were used to adjust for potential confounders. RESULTS: Of the 271 ED visits from 137 patients, 19.2% resulted in shunt revision. Increased ventricle size on imaging (OR 11.38, p < 0.001), shunt site swelling (OR 9.04, p = 0.01), bradycardia (OR 7.08, p < 0.001), and lethargy (OR 5.77, p < 0.001) were significantly associated with shunt revision. Seizure-like activity was inversely related to revision needs (OR 0.24, p < 0.001). Patients with private or self-pay insurance were more likely to undergo revision compared with those with public insurance (p = 0.028). Multivariate analysis further confirmed the significant associations of increased ventricle size, lethargy, and bradycardia with shunt revision, while also revealing that seizure-like activity inversely affected the likelihood of revision. Patients with severe cognitive and language disabilities were more likely to be admitted to the hospital from the ED but were not more likely to undergo revision. CONCLUSIONS: Clinical signs such as increased ventricle size, shunt site swelling, bradycardia, and lethargy may be strong predictors of the need for shunt revision in pediatric patients presenting to the ED with concerns of shunt malfunction. Socioeconomic factors play a less clear role in predicting shunt revision and admission from the ED; however, the nature of their influence is unclear. These findings can help inform clinical decision-making and optimize resource utilization in the ED.

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.

A re-evaluation of the Endoscopic Third Ventriculostomy Success Score: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: The Hydrocephalus Clinical Research Network (HCRN) conducted a prospective study 1) to determine if a new, better-performing version of the Endoscopic Third Ventriculostomy Success Score (ETVSS) could be developed, 2) to explore the performance characteristics of the original ETVSS in a modern endoscopic third ventriculostomy (ETV) cohort, and 3) to determine if the addition of radiological variables to the ETVSS improved its predictive abilities. METHODS: From April 2008 to August 2019, children (corrected age ≤ 17.5 years) who underwent a first-time ETV for hydrocephalus were included in a prospective multicenter HCRN study. All children had at least 6 months of clinical follow-up and were followed since the index ETV in the HCRN Core Data Registry. Children who underwent choroid plexus cauterization were excluded. Outcome (ETV success) was defined as the lack of ETV failure within 6 months of the index procedure. Kaplan-Meier curves were constructed to evaluate time-dependent variables. Multivariable binary logistic models were built to evaluate predictors of ETV success. Model performance was evaluated with Hosmer-Lemeshow and Harrell's C statistics. RESULTS: Seven hundred sixty-one children underwent a first-time ETV. The rate of 6-month ETV success was 76%. The Hosmer-Lemeshow and Harrell's C statistics of the logistic model containing more granular age and etiology categorizations did not differ significantly from a model containing the ETVSS categories. In children ≥ 12 months of age with ETVSSs of 50 or 60, the original ETVSS underestimated success, but this analysis was limited by a small sample size. Fronto-occipital horn ratio (p = 0.37), maximum width of the third ventricle (p = 0.39), and downward concavity of the floor of the third ventricle (p = 0.63) did not predict ETV success. A possible association between the degree of prepontine adhesions on preoperative MRI and ETV success was detected, but this did not reach statistical significance. CONCLUSIONS: This modern, multicenter study of ETV success shows that the original ETVSS continues to demonstrate good predictive ability, which was not substantially improved with a new success score. There might be an association between preoperative prepontine adhesions and ETV success, and this needs to be evaluated in a future large prospective study.

Unraveling the Complexity of the Senescence-Associated Secretory Phenotype in Adamantinomatous Craniopharyngioma Using Multi-Modal Machine Learning Analysis.

BACKGROUND: Cellular senescence can have positive and negative effects on the body, including aiding in damage repair and facilitating tumor growth. Adamantinomatous Craniopharyngioma (ACP), the most common pediatric sellar/suprasellar brain tumor, poses significant treatment challenges. Recent studies suggest that senescent cells in ACP tumors may contribute to tumor growth and invasion by releasing a Senesecence-Associated Secretory Phenotype (SASP). However, a detailed analysis of these characteristics has yet to be completed. METHODS: We analyzed primary tissue samples from ACP patients using single-cell, single-nuclei, and spatial RNA Sequencing. We performed various analyses, including gene expression clustering, inferred senescence cells from gene expression, and conducted cytokine signaling inference. We utilized LASSO to select essential gene expression pathways associated with senescence. Finally, we validated our findings through immunostaining. RESULTS: We observed significant diversity in gene expression and tissue structure. Key factors such as NFKB, RELA, and SP1 are essential in regulating gene expression, while senescence markers are present throughout the tissue. SPP1 is the most significant cytokine signaling network among ACP cells, while the Wnt signaling pathway predominantly occurs between epithelial and glial cells. Our research has identified links between senescence-associated features and pathways, such as PI3K/Akt/mTOR, MYC, FZD, and Hedgehog, with increased P53 expression associated with senescence in these cells. CONCLUSIONS: A complex interplay between cellular senescence, cytokine signaling, and gene expression pathways underlies ACP development. Further research is crucial to understand how these elements interact to create novel therapeutic approaches for patients with ACP.

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.

Midwave resonant cavity infrared detectors (RCIDs) with suppressed background noise.

We report a resonant cavity infrared detector (RCID) with an InAsSb/InAs superlattice absorber with a thickness of only ≈ 100 nm, a 33-period GaAs/Al0.92Ga0.08As distributed Bragg reflector bottom mirror, and a Ge/SiO2/Ge top mirror. At a low bias voltage of 150 mV, the external quantum efficiency (EQE) reaches 58% at the resonance wavelength λres ≈ 4.6 µm, with linewidth δλ = 19-27 nm. The thermal background current for a realistic system scenario with f/4 optic that views a 300 K scene is estimated by integrating the photocurrent generated by background spanning the entire mid-IR spectral band (3-5 µm). The resulting specific detectivity is a factor of 3 lower than for a state-of-the-art broadband HgCdTe device at 300 K, where dark current dominates the noise. However, at 125 K where the suppression of background noise becomes critical, the estimated specific detectivity D* of 5.5 × 1012 cm Hz½/W is more than 3× higher. This occurs despite a non-optimal absorber cut-off that causes the EQE to decrease rapidly with decreasing temperature, e.g., to 33% at 125 K. The present RCID's advantage over the broadband device depends critically on its low EQE at non-resonance wavelengths: ≤ 1% in the range 3.9-5.5 µm. Simulations using NRL MULTIBANDS indicate that impact ionization in the bottom contact and absorber layers dominates the dark current at near ambient temperatures. We expect future design modifications to substantially enhance D* throughout the investigated temperature range of 100-300 K.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Surgical Interventions.

BACKGROUND: Chiari malformation type I (CIM) diagnoses have increased in recent years. Controversy regarding the best operative management prompted a review of the literature to offer guidance on surgical interventions. OBJECTIVE: To assess the literature to determine (1) whether posterior fossa decompression or posterior fossa decompression with duraplasty is more effective in preoperative symptom resolution; (2) whether there is benefit from cerebellar tonsillar resection/reduction; (3) the role of intraoperative neuromonitoring; (4) in patients with a syrinx, how long should a syrinx be observed for improvement before additional surgery is performed; and 5) what is the optimal duration of follow-up care after preoperative symptom resolution. METHODS: A systematic review was performed using the National Library of Medicine/PubMed and Embase databases for studies on CIM in children and adults. The most appropriate surgical interventions, the use of neuromonitoring, and clinical improvement during follow-up were reviewed for studies published between 1946 and January 23, 2021. RESULTS: A total of 80 studies met inclusion criteria. Posterior fossa decompression with or without duraplasty or cerebellar tonsil reduction all appeared to show some benefit for symptom relief and syrinx reduction. There was insufficient evidence to determine whether duraplasty or cerebellar tonsil reduction was needed for specific patient groups. There was no strong correlation between symptom relief and syringomyelia resolution. Many surgeons follow patients for 6-12 months before considering reoperation for persistent syringomyelia. No benefit or harm was seen with the use of neuromonitoring. CONCLUSION: This evidence-based clinical guidelines for the treatment of CIM provide 1 Class II and 4 Class III recommendations. In patients with CIM with or without syringomyelia, treatment options include bone decompression with or without duraplasty or cerebellar tonsil reduction. Improved syrinx resolution may potentially be seen with dural patch grafting. Symptom resolution and syrinx resolution did not correlate directly. Reoperation for a persistent syrinx was potentially beneficial if the syrinx had not improved 6 to 12 months after the initial operation. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/3-surgical-interventions .

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Diagnosis.

BACKGROUND: Chiari I malformation (CIM) is characterized by descent of the cerebellar tonsils through the foramen magnum, potentially causing symptoms from compression or obstruction of the flow of cerebrospinal fluid. Diagnosis and treatment of CIM is varied, and guidelines produced through systematic review may be helpful for clinicians. OBJECTIVE: To perform a systematic review of the medical literature to answer specific questions on the diagnosis and treatment of CIM. METHODS: PubMed and Embase were queried between 1946 and January 23, 2021, using the search strategies provided in Appendix I of the full guidelines. RESULTS: The literature search yielded 567 abstracts, of which 151 were selected for full-text review, 109 were then rejected for not meeting the inclusion criteria or for being off-topic, and 42 were included in this systematic review. CONCLUSION: Three Grade C recommendations were made based on Level III evidence. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/1-imaging .

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Symptoms.

BACKGROUND: Chiari I malformation (CIM) is characterized by descent of the cerebellar tonsils through the foramen magnum, potentially causing symptoms from compression or obstruction of the flow of cerebrospinal fluid. Diagnosis and treatment of CIM is varied, and guidelines produced through systematic review may be helpful for clinicians. OBJECTIVE: To perform a systematic review of the medical literature to answer specific questions on the diagnosis and treatment of CIM. METHODS: PubMed and Embase were queried between 1946 and January 23, 2021, using the search strategies provided in Appendix I of the full guidelines. RESULTS: The literature search yielded 430 abstracts, of which 79 were selected for full-text review, 44 were then rejected for not meeting the inclusion criteria or for being off-topic, and 35 were included in this systematic review. CONCLUSION: Four Grade C recommendations were made based on Class III evidence, and 1 question had insufficient evidence. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/2-symptoms .

Seq-ing the SINEs of central nervous system tumors in cerebrospinal fluid.

It is often challenging to distinguish cancerous from non-cancerous lesions in the brain using conventional diagnostic approaches. We introduce an analytic technique called Real-CSF (repetitive element aneuploidy sequencing in CSF) to detect cancers of the central nervous system from evaluation of DNA in the cerebrospinal fluid (CSF). Short interspersed nuclear elements (SINEs) are PCR amplified with a single primer pair, and the PCR products are evaluated by next-generation sequencing. Real-CSF assesses genome-wide copy-number alterations as well as focal amplifications of selected oncogenes. Real-CSF was applied to 280 CSF samples and correctly identified 67% of 184 cancerous and 96% of 96 non-cancerous brain lesions. CSF analysis was considerably more sensitive than standard-of-care cytology and plasma cell-free DNA analysis in the same patients. Real-CSF therefore has the capacity to be used in combination with other clinical, radiologic, and laboratory-based data to inform the diagnosis and management of patients with suspected cancers of the brain.

Perioperative Management of Pediatric Patients with Moyamoya Arteriopathy.

Pediatric patients with moyamoya arteriopathy are at high risk for developing new onset transient or permanent neurologic deficits secondary to cerebral hypoperfusion, particularly in the perioperative period. It is therefore essential to carefully manage these patients in a multidisciplinary, coordinated effort to reduce the risk of new permanent neurologic deficits. However, little has been published on perioperative management of pediatric patients with moyamoya, particularly in the early postoperative period during intensive care unit admission. Our pediatric neurocritical care team sought to create a multidisciplinary periprocedural evidence- and consensus-based care pathway for high-risk pediatric patients with moyamoya arteriopathy undergoing anesthesia for any reason to decrease the incidence of periprocedural stroke or transient ischemic attack (TIA). We reviewed the literature to identify risk factors associated with perioperative stroke or TIA among patients with moyamoya and to gather data supporting specific perioperative management strategies. A multidisciplinary team from pediatric anesthesia, neurocritical care, nursing, child life, neurosurgery, interventional neuroradiology, neurology, and hematology created a care pathway for children with moyamoya undergoing anesthesia, classifying them as either high or standard risk, and applying an individualized perioperative management plan to high-risk patients. The incidence of neurologic sequelae before and after pathway implementation will be compared in future studies.

The Neurodevelopmental and Molecular Landscape of Medulloblastoma Subgroups: Current Targets and the Potential for Combined Therapies.

Medulloblastoma is the most common malignant pediatric brain tumor and is associated with significant morbidity and mortality in the pediatric population. Despite the use of multiple therapeutic approaches consisting of surgical resection, craniospinal irradiation, and multiagent chemotherapy, the prognosis of many patients with medulloblastoma remains dismal. Additionally, the high doses of radiation and the chemotherapeutic agents used are associated with significant short- and long-term complications and adverse effects, most notably neurocognitive delay. Hence, there is an urgent need for the development and clinical integration of targeted treatment regimens with greater efficacy and superior safety profiles. Since the adoption of the molecular-based classification of medulloblastoma into wingless (WNT) activated, sonic hedgehog (SHH) activated, group 3, and group 4, research efforts have been directed towards unraveling the genetic, epigenetic, transcriptomic, and proteomic profiles of each subtype. This review aims to delineate the progress that has been made in characterizing the neurodevelopmental and molecular features of each medulloblastoma subtype. It further delves into the implications that these characteristics have on the development of subgroup-specific targeted therapeutic agents. Furthermore, it highlights potential future avenues for combining multiple agents or strategies in order to obtain augmented effects and evade the development of treatment resistance in tumors.

Comparison of outcomes in the management of abdominal pseudocyst in children with shunted hydrocephalus: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: Abdominal pseudocyst (APC) can cause distal site failure in children with ventriculoperitoneal shunts and is specifically designated as an infection in Hydrocephalus Clinical Research Network (HCRN) protocols. Specific management and outcomes of children with APCs have not been reported in a multicenter study. In this study, the authors investigated the management and outcomes of APC in children with shunted hydrocephalus who were treated at centers in the HCRN. METHODS: The HCRN Registry was queried to identify children < 18 years old with shunts who were diagnosed with an APC (i.e., a loculated abdominal fluid collection containing the peritoneal catheter with abdominal distention and/or displacement of peritoneal contents). The primary outcome was shunt failure after APC treatment. The primary variable was reimplantation of the distal catheter after pseudocyst treatment back into the peritoneum versus implantation in a nonperitoneal site. Other risk factors for shunt failure after APC treatment and variability in APC management were investigated. RESULTS: Among 141 children from 14 centers who underwent first-time management of an APC over a 14-year period, the median time from previous shunt surgery to APC diagnosis was 3.8 months. Overall, 17.7% of children had a positive culture: APC cultures were positive in 14.2% and CSF cultures in 15.6%. Six other children underwent shunt revision without removal; all underwent reoperation within 1 month. There was no difference in shunt survival (log-rank test, p = 0.42) or number of subsequent revisions within 6, 12, or 24 months for shunts reimplanted in the abdomen versus those implanted in a nonperitoneal location. Nonperitoneal implantation was associated with more noninfectious revisions (42.3% vs 22.9%, p = 0.019), whereas infection was more common after reimplantation in the abdomen (25.7% vs 7.0%, p = 0.003). Univariable analysis demonstrated that younger age at APC diagnosis (8.3 vs 12.2 years, p = 0.006) and prior shunt procedure within 12 weeks of APC diagnosis (59.5% vs 40.5%, p = 0.012) were associated with shunt failure after APC treatment. Multivariable modeling confirmed that prior shunt surgery within 12 weeks of APC diagnosis was independently associated with failure (HR 1.79 [95% CI 1.04-3.07], p = 0.035). CONCLUSIONS: In the HCRN, APCs in the setting of CSF shunts are usually managed with externalization. Shunt surgery within 12 weeks of APC diagnosis was associated with risk of failure after APC treatment. Although no differences were found in overall shunt failure rate, noninfectious shunt revisions were more common in the nonperitoneal distal catheter sites, and infection was a more common reason for failure after reimplantation of the shunt in the abdomen.

Treatment of hydrocephalus following posterior fossa tumor resection: a multicenter collaboration from the Hydrocephalus Clinical Research Network.

OBJECTIVE: Persistent hydrocephalus following posterior fossa brain tumor (PFBT) resection is a common cause of morbidity in pediatric brain tumor patients, for which the optimal treatment is debated. The purpose of this study was to compare treatment outcomes between VPS and ETV in patients with persistent hydrocephalus following surgical resection of a PFBT. METHODS: A post-hoc analysis was performed of the Hydrocephalus Clinical Research Network (HCRN) prospective observational study evaluating VPS and ETV for pediatric patients. Children who experienced hydrocephalus secondary to PFBT from 2008 to 2021 were included. Primary outcomes were VPS/ETV treatment failure and time-to-failure (TTF). RESULTS: Among 241 patients, the VPS (183) and ETV (58) groups were similar in age, extent of tumor resection, and preoperative ETV Success Score. There was no difference in overall treatment failure between VPS and ETV (33.9% vs 31.0%, p = 0.751). However, mean TTF was shorter for ETV than VPS (0.45 years vs 1.30 years, p = 0.001). While major complication profiles were similar, compared to VPS, ETV patients had relatively higher incidence of minor CSF leak (10.3% vs. 1.1%, p = 0.003) and pseudomeningocele (12.1% vs 3.3%, p = 0.02). No ETV failures were identified beyond 3 years, while shunt failures occurred beyond 5 years. Shunt infections occurred in 5.5% of the VPS cohort. CONCLUSIONS: ETV and VPS offer similar overall success rates for PFBT-related postoperative hydrocephalus. ETV failure occurs earlier, while susceptibility to VPS failure persists beyond 5 years. Tumor histology and grade may be considered when selecting the optimal means of CSF diversion.

Spinal dysraphism in exstrophy: a single-center study of a 39-year prospective database.

OBJECTIVE: The two main objectives of this study were to explore the rate of spinal dysraphism within bladder and cloacal exstrophy and to analyze the relationship between spinal dysraphism surgery, including timing of spinal dysraphism surgery, with urological and neurological outcomes. METHODS: A prospectively maintained IRB-approved database of pediatric exstrophy patients treated from 1982 to 2021 was retrospectively reviewed for patients with spinal dysraphism. Spinal dysraphism was categorized into the following 7 subtypes: lipoma-based closed defect, myelomeningocele, meningocele, diastematomyelia, myelocystocele, low-lying conus with tethered cord/fatty filum, and sacral bony defect. Other factors assessed included patient demographic characteristics, type of spinal dysraphism procedure, reoperation, complication, presence of other neurological problems (e.g., hydrocephalus, Chiari malformation), neurological status, and urological function. RESULTS: Analysis revealed that 114/1401 patients had coexisting spinal dysraphism. Of these 114, sufficient records including type of dysraphism were available for 54. Spinal dysraphism was most common within cloacal exstrophy (83.3% [45/54 patients]), followed by cloacal exstrophy variants (9.3% [5/54]), classic bladder exstrophy (3.7% [2/54]), and classic bladder exstrophy variants (3.7% [2/54]). Within spinal dysraphism, lipoma-based closed defects (63.0% [34/54]) and low-lying conus with tethered cord/fatty filum (11.1% [6/54]) were most common. Hydrocephalus and Chiari malformation occurred in 24.1% (13/54) and 11.1% (6/54) of patients. All 13 patients with hydrocephalus underwent shunt placement. Among those who underwent neurosurgical intervention, the complication rate for spinal dysraphism was 14.6% (7/48). Motor function data were available for 41 patients and revealed that motor function declined for 2/41 (4.8%) patients and improved for 6/41 (14.6%) after neurosurgery. There was no statistical difference in lower-extremity motor outcome related to timing of neurosurgery and exstrophy closure. CONCLUSIONS: The authors have reported the surgical management and outcomes of patients with exstrophy and coexisting spinal dysraphism (n = 54). In 54 patients, spinal dysraphism was most common in the subset of patients with cloacal exstrophy (83.3%). Lipoma-based closed defects (63.0%) and low-lying conus with tethered cord/fatty filum (11.1%) were the most common, and the rates of hydrocephalus and Chiari malformation were 24.1% and 11.1%, respectively. There was no difference in lower-extremity motor outcome related to timing of neurosurgery and exstrophy closure.

Same-day versus staged revascularization of bilateral moyamoya arteriopathy in pediatric patients.

PURPOSE: To compare the outcomes of conducting left and right hemisphere surgical revascularization on the same day versus different days for bilateral pediatric moyamoya arteriopathy patients. METHODS: We retrospectively analyzed mortality, stroke, and transient neurologic event (TNE) rates in North American bilateral pediatric moyamoya arteriopathy patients who underwent bilateral cerebral revascularization. RESULTS: A total of 38 pediatric (≤ 18 years old) patients at our institution underwent bilateral cerebral revascularization for moyamoya arteriopathy. Of these patients, 24 (63.2%) had both operations on the same day and 14 (36.8%) had the two operations on different days. The average length of stay for patients who underwent same-day bilateral revascularization was 6.9 ± 2.0 days and the average length of stay for each operation for patients who underwent staged bilateral revascularization was 4.5 ± 1.4 days, p = 0.001. While there were 7 (14.6%) postoperative strokes in patients who had both hemispheres revascularized on the same day, 0 (0%) strokes occurred in hemispheres after they had been operated on in the staged cohort, p = 0.042. Additionally, the postoperative stroke-free survival time in the ipsilateral hemisphere and TNE-free survival time were significantly longer in patients in the staged revascularization cohort. CONCLUSION: Same-day bilateral revascularization was associated with longer length of stay per operation, higher rate of ipsilateral stroke, and shorter postoperative TNE-free and stroke-free survival time in the revascularized hemisphere.

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.

Postnatal Progressive Craniosynostosis in Syndromic Conditions: Two Patients With Saethre-Chotzen Due to TWIST1 Gene Deletions and Review of the Literature.

Saethre-Chotzen syndrome (SCS) is a known craniosynostosis syndrome with a variable presentation of craniofacial and somatic involvement. Congenital coronal craniosynostosis is most commonly observed in SCS; however, progressive postnatal craniosynostosis of other sutures has been reported. The authors present 2 infants with progressive postnatal craniosynostosis and SCS caused by chromosome 7p deletions including the TWIST1 gene. The evolution of their clinical features and a literature review of patients with syndromic, postnatal progressive craniosynostosis illustrate the importance of longitudinal observation and management of these patients.

Hydrocephalus surveillance following CSF diversion: a modified Delphi study.

OBJECTIVE: Long-term follow-up is often recommended for patients with hydrocephalus, but the frequency of clinical follow-up, timing and modality of imaging, and duration of surveillance have not been clearly defined. Here, the authors used the modified Delphi method to identify areas of consensus regarding the modality, frequency, and duration of hydrocephalus surveillance following surgical treatment. METHODS: Pediatric neurosurgeons serving as institutional liaisons to the Hydrocephalus Clinical Research Network (HCRN), or its implementation/quality improvement arm (HCRNq), were invited to participate in this modified Delphi study. Thirty-seven consensus statements were generated and distributed via an anonymous electronic survey, with responses structured as a 4-point Likert scale (strongly agree, agree, disagree, strongly disagree). A subsequent, virtual meeting offered the opportunity for open discussion and modification of the statements in an effort to reach consensus (defined as ≥ 80% agreement or disagreement). RESULTS: Nineteen pediatric neurosurgeons participated in the first round, after which 15 statements reached consensus. During the second round, 14 participants met virtually for review and discussion. Some statements were modified and 2 statements were combined, resulting in a total of 36 statements. At the conclusion of the session, consensus was achieved for 17 statements regarding the following: 1) the role of standardization; 2) preferred imaging modalities; 3) postoperative follow-up after shunt surgery (subdivided into immediate postoperative imaging, delayed postoperative imaging, routine clinical surveillance, and routine radiological surveillance); and 4) postoperative follow-up after an endoscopic third ventriculostomy. Consensus could not be achieved for 19 statements. CONCLUSIONS: Using the modified Delphi method, 17 consensus statements were developed with respect to both clinical and radiological follow-up after a shunt or endoscopic third ventriculostomy. The frequency, modality, and duration of surveillance were addressed, highlighting areas in which no clear data exist to guide clinical practice. Although further studies are needed to evaluate the clinical utility and cost-effectiveness of hydrocephalus surveillance, the current study provides a framework to guide future efforts to develop standardized clinical protocols for the postoperative surveillance of patients with hydrocephalus. Ultimately, the standardization of hydrocephalus surveillance has the potential to improve patient care as well as optimize the use of healthcare resources.