Faculty Bibliography

BACKGROUND:Sturge-Weber syndrome (SWS) is a congenital neurocutaneous disorder characterized by angiomas of the face, choroid, and leptomeninges. Seizures in these children often present within the first 2 years of life. SWS is typically unilateral, but bilateral SWS occurs in approximately 15% of cases. Bilateral SWS is associated with earlier seizure onset and poorer cognitive, developmental, and functional outcomes. More than half of children with SWS develop drug-resistant epilepsy requiring surgical intervention. Hemispherotomy has been established as a successful treatment for unilateral SWS, but resective surgery has traditionally not been considered a treatment option for patients with bilateral disease. OBSERVATIONS/METHODS:In this report, the authors present the cases of 4 children (7 months-2 years of age) with bilateral SWS and drug-resistant epilepsy with a unilateral electroencephalography predominance. After a multidisciplinary conference in each case, all children were successfully treated with unilateral hemispherotomy. These patients achieved prolonged periods of seizure freedom postoperatively, a better quality of life, and demonstrated improved developmental progress at long-term follow-up. LESSONS/CONCLUSIONS:This case series suggests that functional hemispherotomy may be a safe and effective therapeutic option for improving seizure burden in cases of bilateral drug-resistant SWS with asymmetric seizure burden. https://thejns.org/doi/10.3171/CASE25125.

INTRODUCTION/BACKGROUND:Traumatic brain injury (TBI) is the leading cause of pediatric disability. Most pediatric TBIs are mild but can result in long-term cognitive and functional impairments. Outpatient follow-up is essential to detect post-concussive symptoms and aid recovery. METHODS:All patients 3-18 years of age with positive TBI findings on CT or MRI from 2018-2024 were retrospectively reviewed. Follow-up was defined as an appointment with neurology, neuropsychology, neurosurgery, or physical medicine and rehabilitation within three months of discharge. Analyses were performed with appropriate Chi-squared, Fisher's exact, Mann-Whitney U, or t-tests. RESULTS:Fifty-seven patients (41 male, mean age 11.4 years) were identified, with mild TBIs (GCS 13-15) comprising 41/57 (71.9%). Four patients (7.0%) died from their injury. Of 53 surviving patients, 20 (37.7%) had follow-up appointments scheduled for them at discharge, seven (13.2%) were given a specific date and contact number, 17 (32.1%) received service referrals without a specific date, and eight (15.1%) received nonspecific directions or were directed only to follow-up with non-neuroscience services. Within three months, 32 (60.4%) patients followed up, though only 22/53 (41.5%) patients saw a non-surgical neuroscience discipline. Patients who followed up were more likely to have undergone neurosurgery (p = 0.007) or any surgical procedure at all (p = 0.007). They were also more likely to have a shorter hospital length of stay (p = 0.021). Discharge instruction type was significantly associated with follow-up (p = 0.0013); 62.5% of patients who followed up had an appointment scheduled for them or were given a specific date versus 33.4% of patients who did not follow-up. Conversely, 38.1% of patients without follow-up received nonspecific instructions or were told to follow-up with non-neuroscience specialties. This finding remained significant when excluding patients with severe TBI. Follow-up had no significant associations with demographics, injury severity, or insurance type. CONCLUSION/CONCLUSIONS:Patient-centered discharge instructions with detailed service referrals increase access to critical follow-up care. Children with TBIs should have follow-up care arranged regardless of injury severity. Larger multicenter studies are needed to validate these findings.

OBJECTIVE:Endoscopic third ventriculostomy (ETV) is a treatment option for obstructive hydrocephalus; reported success rates vary. We investigated immediate postoperative magnetic resonance imaging (MRI) to evaluate the role of imaging parameters associated with outcomes. METHODS:Retrospective chart review was performed patients undergoing initial ETV between 2005 -2019. Patients with pre- and postoperative MRI with follow-up >one year were included. The following were noted: changes in subarachnoid CSF, third ventricle diameter (TV), bowing of the TV floor, and postoperative flow void. Kaplan-Meier survival methods were used to assess ETV success, Univariable and multivariable Cox proportional-hazards models were fitted to assess factors contributing to ETV success. RESULTS:Fifty-eight subjects were included. Nineteen (32.8%) experienced failure within one year, individually, no single imaging parameter predicted success. However, all cases with failure had no identifiable flow void. Any postoperative radiological change was not consistently associated with decreased odds of failure. Obstructive hydrocephalus treated with ETV demonstrated significantly better ETV success than patients treated for non-obstructive hydrocephalus Inter-observer reliability was moderate for two of the radiological variables and substantial for one of the radiological variables. CONCLUSIONS:Individually none of the qualitative radiologic parameters measured in our study predicted ETV success. Absence of a flow void predicted ETV failure, but additional studies are needed to determine its true negative predictive value. Inability to clarify which specific parameter predicts success, reflects the limited role of immediate postoperative imaging in influencing clinical management.

UNLABELLED:DNA methylation is an essential molecular assay for central nervous system (CNS) tumor diagnostics. While some fusions define specific brain tumors, others occur across many different diagnoses. We performed a retrospective analysis of 219 primary CNS tumors with whole genome DNA methylation and RNA next-generation sequencing. DNA methylation profiling results were compared with RNAseq detected gene fusions. We detected 105 rare fusions involving 31 driver genes, including 23 fusions previously not implicated in brain tumors. In addition, we identified 6 multi-fusion tumors. Rare fusions and multi-fusion events can impact the diagnostic accuracy of DNA methylation by decreasing confidence in the result, such as BRAF, RAF, or FGFR1 fusions, or result in a complete mismatch, such as NTRK, EWSR1, FGFR, and ALK fusions. IMPLICATIONS/UNASSIGNED:DNA methylation signatures need to be interpreted in the context of pathology and discordant results warrant testing for novel and rare gene fusions.

OBJECTIVES/OBJECTIVE:Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, a large variability in outcomes remains. Identifying ideal hemispherectomy candidates is imperative to maximize the potential for seizure freedom. The objective was to develop an online, freely-accesible tool that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy to provide clinicians accessible and reliable prognostic information to complement clinical judgement. 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 duration based on a combination of variables identified by clinical judgement and inferential statistics as predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the (iNEST) website. RESULTS:The selected variables for inclusion in the final model included the 5 original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral FDG-PET hypometabolism) and 3 additional variables (age at surgery, history of infantile spasms, and magnetic resonance (MR) imaging lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, older age at surgery, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to side of surgery, contralateral MR imaging lesion, non-lesional MR imaging, non-stroke etiologies, and history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE/CONCLUSIONS:Online calculators are efficient, cost-free tools that can facilitate physicians in risk-estimation and inform joint decision-making with families, potentially leading to greater satisfaction. Although the HOPS data was previously validated in the first analysis, the authors encourage prospective external validation of this new tool.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Spine surgery has advanced in concert with our deeper understanding of its elements. Narrowly focused bibliometric analyses have been conducted previously, but never on the entire corpus of the field. Using big data and bibliometrics, we appraised the entire corpus of spine surgery publications to study the evolution of the specialty as a scholarly field since 1900. METHODS:We queried Web of Science for all contents from 13 major publications dedicated to spine surgery. We next queried by topic [topic = (spine OR spinal OR vertebrae OR vertebral OR intervertebral OR disc OR disk)]; these results were filtered to include articles published by 49 other publications that were manually determined to contain pertinent articles. Articles, along with their metadata, were exported. Statistical and bibliometric analyses were performed using the Bibliometrix R package and various Python packages. RESULTS:Eighty-five thousand five hundred articles from 62 journals and 134 707 unique authors were identified. The annual growth rate of publications was 2.78%, with a surge after 1980, concurrent with the growth of specialized journals. International coauthorship, absent before 1970, increased exponentially with the formation of influential spine study groups. Reference publication year spectroscopy allowed us to identify 200 articles that comprise the historical roots of modern spine surgery and each of its subdisciplines. We mapped the emergence of new topics and saw a recent lexical evolution toward outcomes- and patient-centric terms. Female and minority coauthorship has increased since 1990, but remains low, and disparities across major publications persist. CONCLUSION/CONCLUSIONS:The field of spine surgery was borne from pioneering individuals who published their findings in a variety of journals. The renaissance of spine surgery has been powered by international collaboration and is increasingly outcomes focused. While spine surgery is gradually becoming more diverse, there is a clear need for further promotion and outreach to under-represented populations.

Diffuse spinal cord gliomas (SCGs) are rare tumors associated with a high morbidity and mortality that affect both pediatric and adult populations. In this retrospective study, we sought to characterize the clinical, pathological, and molecular features of diffuse SCG in 22 patients with histological and molecular analyses. The median age of our cohort was 23.64 years (range 1-82) and the overall median survival was 397 days. K27M mutation was significantly more prevalent in males compared to females. Gross total resection and chemotherapy were associated with improved survival, compared to biopsy and no chemotherapy. While there was no association between tumor grade, K27M status (p = 0.366) or radiation (p = 0.772), and survival, males showed a trend toward shorter survival. K27M mutant tumors showed increased chromosomal instability and a distinct DNA methylation signature.