Predicting blunt cerebrovascular injury in pediatric trauma: Validation of the Utah Score

Risk factors for blunt cerebrovascular injury (BCVI) may differ between children and adults, suggesting that children at low risk for BCVI after trauma receive unnecessary computed tomography angiography (CTA) and high-dose radiation. We previously developed a score for predicting pediatric BCVI based on retrospective cohort analysis. Our objective is to externally validate this prediction score with a retrospective multi-institutional cohort. We included patients who underwent CTA for traumatic cranial injury at four pediatric Level I trauma centers. Each patient in the validation cohort was scored using the “Utah Score” and classified as high or low risk. Before analysis, we defined a misclassification rate <25% as validating the Utah Score. Six hundred forty-five patients (mean age 8.6 ± 5.4 years; 63.4% males) underwent screening for BCVI via CTA. The validation cohort was 411 patients from three sites compared with the training cohort of 234 patients. Twenty-two BCVIs (5.4%) were identified in the validation cohort. The Utah Score was significantly associated with BCVIs in the validation cohort (odds ratio 8.1 [3.3, 19.8], p < 0.001) and discriminated well in the validation cohort (area under the curve 72%). When the Utah Score was applied to the validation cohort, the sensitivity was 59%, specificity was 85%, positive predictive value was 18%, and negative predictive value was 97%. The Utah Score misclassified 16.6% of patients in the validation cohort. The Utah Score for predicting BCVI in pediatric trauma patients was validated with a low misclassification rate using a large, independent, multicenter cohort. Its implementation in the clinical setting may reduce the use of CTA in low-risk patients

Multi-Center Validation of the McGovern Pediatric Blunt Cerebrovascular Injury Screening Score

Blunt cerebrovascular injury (BCVI) is defined as blunt trauma to the head and neck leading to damage to the vertebral and/or carotid arteries; debate exists regarding which children are considered at high risk for BCVI and in need of angiographic/vessel imaging. We previously proposed a screening tool, the McGovern score, to identify pediatric trauma patients at high risk for BCVI, and we aim to validate the McGovern score by pooling data from multiple pediatric trauma centers. This is a multi-center, hospital-based, cohort study from all prospectively registered pediatric (age) trauma patients who presented to the emergency department (ED) between 2003 and 2017 at six Level 1 pediatric trauma centers. The registry was retrospectively queried for patients who received a computed tomography angiogram (CTA) as a screening method for BCVI. Age, length of follow-up, mechanism of injury (MOI), arrival Glasgow Coma Scale (GCS) score, and focal neurological deficit were recorded. Radiological variables queried were the presence of a carotid canal fracture, petrous temporal bone fracture, and CT presence of infarction. Patients with BCVI were queried for mode of treatment, type of intracranial injury, artery damaged, and BCVI injury grade. The McGovern score was calculated for all patients who underwent CTA across all data groups. A total of 1012 patients underwent CTA; 72 of these patients were found to have BCVI, 51 of which were in the validation cohort. Across all data groups, the McGovern score has a \u3e80% sensitivity (SN) and \u3e98% negative predictive value (NPV). The McGovern score for pediatric BCVI is an effective, generalizable screening tool

Development of an online calculator for the prediction of seizure freedom following pediatric hemispherectomy using the Hemispherectomy Outcome Prediction Scale (HOPS)

OBJECTIVES Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy. METHODS Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/). RESULTS The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator

Amperometric biosensor based on horseradish peroxidase immobilised magnetic microparticles

Magnetised silica-based microparticles (MMPs) (5 μm) with a high density of nanopores were used for horseradish peroxidase (HRP) immobilization and amperometric biosensor development in batch conditions. The resulting biosensor was applied to study the peroxidation of clozapine (CLZ) which is a dibenzoazepine drug often used in the treatment of neurological disorders. The amperometric response corresponded to the electroreduction of CLZ-oxidized products namely a nitrenium cation and quinoneimine derivative of CLZ. Despite a relatively low amount of immobilized HRP (0.3 μmol/g), clozapine quantification in the micromolar concentration range was achieved by the use of a magnetized solid paraffin carbon paste electrode for microparticles attraction. Diffusion of substrate and products of the enzyme reaction within the nanopores were identified as limiting factors in the biosensor response. This amperometric biosensor configuration has number of interesting advantages such as ease and reproducible microparticle layer renewing, low enzyme consumption, controlled surface immobilization, protective enzyme microenvironment etc. © 2005 Elsevier B.V. All rights reserved.info:eu-repo/semantics/publishe

Endovascular Thrombectomy for Pediatric Acute Ischemic Stroke: A Multi-Institutional Experience of Technical and Clinical Outcomes

Background: Endovascular thrombectomy is a promising treatment for acute ischemic stroke in children, but outcome and technical data in pediatric patients with large-vessel occlusions are lacking. Objective: To assess technical and clinical outcomes of thrombectomy in pediatric patients. Methods: We undertook a retrospective cohort study of pediatric patients who experienced acute ischemic stroke from April 2017 to April 2019 who had immediate, 30-, and 90-d follow-up. Patients were treated with endovascular thrombectomy at 5 US pediatric tertiary care facilities. We recorded initial and postprocedural modified Thrombolysis in Cerebral Infarction (mTICI) grade ≥ 2b, initial and postprocedural Pediatric National Institutes of Health Stroke Scale (PedNIHSS) score, and pediatric modified Rankin scale (mRS) score 0 to 2 at 90 d. Results: There were 23 thrombectomies in 21 patients (mean age 11.6 ± 4.9 yr, median 11.5, range 2.1-19; 52% female). A total of 19 (83%) thrombectomies resulted in mTICI grade ≥ 2b recanalization. The median PedNIHSS score was 13 on presentation (range 4-33) and 2 (range 0-26) at discharge (mean reduction 11.3 ± 6.1). A total of 14 (66%) patients had a mRS score of 0 to 2 at 30-d follow-up; 18/21 (86%) achieved that by 90 d. The median mRS was 1 (range 0-4) at 30 d and 1 (range 0-5) at 90 d. One patient required a blood transfusion after thrombectomy. Conclusion: In this large series of pediatric patients treated with endovascular thrombectomy, successful recanalization was accomplished via a variety of approaches with excellent clinical outcomes; further prospective longitudinal study is needed

Morphological and ultrastructural investigation of the posterior atlanto-occipital membrane: Comparing children with Chiari malformation type I and controls.

INTRODUCTION: The fibrous posterior atlanto-occipital membrane (PAOM) at the craniocervical junction is typically removed during decompression surgery for Chiari malformation type I (CM-I); however, its importance and ultrastructural architecture have not been investigated in children. We hypothesized that there are structural differences in the PAOM of patients with CM-I and those without. METHODS: In this prospective study, blinded pathological analysis was performed on PAOM specimens from children who had surgery for CM-I and children who had surgery for posterior fossa tumors (controls). Clinical and radiographic data were collected. Statistical analysis included comparisons between the CM-I and control cohorts and correlations with imaging measures. RESULTS: A total of 35 children (mean age at surgery 10.7 years; 94.3% white) with viable specimens for evaluation were enrolled: 24 with CM-I and 11 controls. There were no statistical demographic differences between the two cohorts. Four children had a family history of CM-I and five had a syndromic condition. The cohorts had similar measurements of tonsillar descent, syringomyelia, basion to C2, and condylar-to-C2 vertical axis (all p&gt;0.05). The clival-axial angle was lower in patients with CM-I (138.1 vs. 149.3 degrees, p = 0.016). Morphologically, the PAOM demonstrated statistically higher proportions of disorganized architecture in patients with CM-I (75.0% vs. 36.4%, p = 0.012). There were no differences in PAOM fat, elastin, or collagen percentages overall and no differences in imaging or ultrastructural findings between male and female patients. Posterior fossa volume was lower in children with CM-I (163,234 mm3 vs. 218,305 mm3, p&lt;0.001), a difference that persisted after normalizing for patient height (129.9 vs. 160.9, p = 0.028). CONCLUSIONS: In patients with CM-I, the PAOM demonstrates disorganized architecture compared with that of control patients. This likely represents an anatomic adaptation in the presence of CM-I rather than a pathologic contribution

The transcriptional network for mesenchymal transformation of brain tumours

The inference of transcriptional networks that regulate transitions into physiological or pathological cellular states remains a central challenge in systems biology. A mesenchymal phenotype is the hallmark of tumour aggressiveness in human malignant glioma, but the regulatory programs responsible for implementing the associated molecular signature are largely unknown. Here we show that reverse-engineering and an unbiased interrogation of a glioma-specific regulatory network reveal the transcriptional module that activates expression of mesenchymal genes in malignant glioma. Two transcription factors (C/EBPbeta and STAT3) emerge as synergistic initiators and master regulators of mesenchymal transformation. Ectopic co-expression of C/EBPbeta and STAT3 reprograms neural stem cells along the aberrant mesenchymal lineage, whereas elimination of the two factors in glioma cells leads to collapse of the mesenchymal signature and reduces tumour aggressiveness. In human glioma, expression of C/EBPbeta and STAT3 correlates with mesenchymal differentiation and predicts poor clinical outcome. These results show that the activation of a small regulatory module is necessary and sufficient to initiate and maintain an aberrant phenotypic state in cancer cells

Seizure outcome of pediatric magnetic resonance-guided laser interstitial thermal therapy versus open surgery: A matched noninferiority cohort study

Objective: Minimally invasive magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) has been proposed as an alternative to open epilepsy surgery, to address concerns regarding the risk of open surgery. Our primary hypothesis was that seizure freedom at 1 year after MRgLITT is noninferior to open surgery in children with drug-resistant epilepsy (DRE). The secondary hypothesis was that MRgLITT has fewer complications and shorter hospitalization than surgery. The primary objective was to compare seizure outcome of MRgLITT to open surgery in children with DRE. The secondary objective was to compare complications and length of hospitalization of the two treatments. Methods: This retrospective multicenter cohort study included children with DRE treated with MRgLITT or open surgery with 1-year follow-up. Exclusion criteria were corpus callosotomy, neurostimulation, multilobar or hemispheric surgery, and lesion with maximal dimension \u3e 60 mm. MRgLITT patients were propensity matched to open surgery patients. The primary outcome was seizure freedom at 1 year posttreatment. The difference in seizure freedom was compared using noninferiority test, with noninferiority margin of −10%. The secondary outcomes were complications and length of hospitalization. Results: One hundred eighty-five MRgLITT patients were matched to 185 open surgery patients. Seizure freedom at 1 year follow-up was observed in 89 of 185 (48.1%) MRgLITT and 114 of 185 (61.6%) open surgery patients (difference = −13.5%, one-sided 97.5% confidence interval = −23.8% to ∞, pNoninferiority =.79). The lower confidence interval boundary of −23.8% was below the prespecified noninferiority margin of −10%. Overall complications were lower in MRgLITT compared to open surgery (10.8% vs. 29.2%, respectively, p \u3c.001). Hospitalization was shorter for MRgLITT than open surgery (3.1 ± 2.9 vs. 7.2 ± 6.1 days, p \u3c.001). Significance: Seizure outcome of MRgLITT at 1 year posttreatment was inferior to open surgery. However, MRgLITT has the advantage of better safety profile and shorter hospitalization. The findings will help counsel children and parents on the benefits and risks of MRgLITT and contribute to informed decision-making on treatment options

High-grade glioma before and after treatment with radiation and Avastin: Initial observations

We evaluate the effects of adjuvant treatment with the angiogenesis inhibitor Avastin (bevacizumab) on pathological tissue specimens of high-grade glioma. Tissue from five patients before and after treatment with Avastin was subjected to histological evaluation and compared to four control cases of glioma before and after similar treatment protocols not including bevacizumab. Clinical and radiographic data were reviewed. Histological analysis focused on microvessel density and vascular morphology, and expression patterns of vascular endothelial growth factor–A (VEGF-A) and the hematopoietic stem cell, mesenchymal, and cell motility markers CD34, smooth muscle actin, D2-40, and fascin. All patients with a decrease in microvessel density had a radiographic response, whereas no response was seen in the patients with increased microvessel density. Vascular morphology showed apparent “normalization” after Avastin treatment in two cases, with thin-walled and evenly distributed vessels. VEGF-A expression in tumor cells was increased in two cases and decreased in three and did not correlate with treatment response. There was a trend toward a relative increase of CD34, smooth muscle actin, D2-40, and fascin immunostaining following treatment with Avastin. Specimens from four patients with recurrent malignant gliomas before and after adjuvant treatment (not including bevacizumab) had features dissimilar from our study cases. We conclude that a change in vascular morphology can be observed following anti-angiogenic treatment. There seems to be no correlation between VEGF-A expression and clinical parameters. While the phenomena we describe may not be specific to Avastin, they demonstrate the potential of tissue-based analysis for the discovery of clinically relevant treatment response biomarkers