Simplifying synthesis of the expanding glioblastoma literature: a topic modeling approach.

PURPOSE: Our study aims to discover the leading topics within glioblastoma (GB) research, and to examine if these topics have "hot" or "cold" trends. Additionally, we aim to showcase the potential of natural language processing (NLP) in facilitating research syntheses, offering an efficient strategy to dissect the landscape of academic literature in the realm of GB research. METHODS: The Scopus database was queried using "glioblastoma" as the search term, in the "TITLE" and "KEY" fields. BERTopic, an NLP-based topic modeling (TM) method, was used for probabilistic TM. We specified a minimum topic size of 300 documents and 5% probability cutoff for outlier detection. We labeled topics based on keywords and representative documents and visualized them with word clouds. Linear regression models were utilized to identify "hot" and "cold" topic trends per decade. RESULTS: Our TM analysis categorized 43,329 articles into 15 distinct topics. The most common topics were Genomics, Survival, Drug Delivery, and Imaging, while the least common topics were Surgical Resection, MGMT Methylation, and Exosomes. The hottest topics over the 2020s were Viruses and Oncolytic Therapy, Anticancer Compounds, and Exosomes, while the cold topics were Surgical Resection, Angiogenesis, and Tumor Metabolism. CONCLUSION: Our NLP methodology provided an extensive analysis of GB literature, revealing valuable insights about historical and contemporary patterns difficult to discern with traditional techniques. The outcomes offer guidance for research directions, policy, and identifying emerging trends. Our approach could be applied across research disciplines to summarize and examine scholarly literature, guiding future exploration.

Advancing personalized prognosis in atypical and anaplastic meningiomas through interpretable machine learning models.

PURPOSE: The primary purpose of this study was to utilize machine learning (ML) models to create a web application that can predict survival outcomes for patients diagnosed with atypical and anaplastic meningiomas. METHODS: In this retrospective cohort study, patients diagnosed with WHO grade II and III meningiomas were selected from the National Cancer Database (NCDB) to analyze survival outcomes at 12, 36, and 60 months. Five machine learning algorithms - TabPFN, TabNet, XGBoost, LightGBM, and Random Forest were employed and optimized using the Optuna library for hyperparameter tuning. The top-performing models were then deployed into our web-based application. RESULTS: From the NCDB, 12,197 adult patients diagnosed with histologically confirmed WHO grade II and III meningiomas were retrieved. The mean age was 61 (± 20), and 6,847 (56.1%) of these were females. Performance evaluation indicated that the top-performing models for each outcome were the models built with the TabPFN algorithm. The TabPFN models yielded area under the receiver operating characteristic (AUROC) values of 0.805, 0.781, and 0.815 in predicting 12-, 36-, and 60-month mortality, respectively. CONCLUSION: With the continuous growth of neuro-oncology data, ML algorithms act as key tools in predicting survival outcomes for WHO grade II and III meningioma patients. By incorporating these interpretable models into a web application, we can practically utilize them to improve risk evaluation and prognosis for meningioma patients.

Is there a morphometric cause of Chiari malformation type I? Analysis of existing literature.

Although many etiologies have been proposed for Chiari malformation type I (CM-I), there currently is no singular known cause of CM-I pathogenesis. Advances in imaging have greatly progressed the study of CM-I. This study reviews the literature to determine if an anatomical cause for CM-I could be proposed from morphometric studies in adult CM-I patients. After conducting a literature search using relevant search terms, two authors screened abstracts for relevance. Full-length articles of primary morphometric studies published in peer-reviewed journals were included. Detailed information regarding methodology and symptomatology, craniocervical instability, syringomyelia, operative effects, and genetics were extracted. Forty-six studies met inclusion criteria, averaging 93.2 CM-I patients and 41.4 healthy controls in size. To obtain measurements, 40 studies utilized MRI and 10 utilized CT imaging, whereas 41 analyzed parameters within the posterior fossa and 20 analyzed parameters of the craniovertebral junction. The most commonly measured parameters included clivus length (n = 30), tonsillar position or descent (n = 28), McRae line length (n = 26), and supraocciput length (n = 26). While certain structural anomalies including reduced clivus length have been implicated in CM-I, there is a lack of consensus on how several other morphometric parameters may or may not contribute to its development. Heterogeneity in presentation with respect to the extent of tonsillar descent suggests alternate methods utilizing morphometric measurements that may help to identify CM-I patients and may benefit future research to better understand underlying pathophysiology and sequelae such as syringomyelia.

Exoscopic resection of a parasagittal atypical meningioma.

This video demonstrates use of the Synaptive 3D exoscope to enhance complex meningioma resection. The patient was a 58-year-old female who presented with new-onset seizures. Workup revealed a parasagittal meningioma over the bilateral cortices. She was started on 750 mg of Keppra twice daily and tapered dexamethasone and discharged. MR venography demonstrated segmental occlusion of the superior sagittal sinus. She then underwent a diagnostic angiogram and tumor Onyx embolization of the bilateral middle meningeal artery feeders. She then underwent a craniotomy for meningioma resection using 3D exoscope guidance. She awoke with a stable examination in the intensive care unit and worked with physical therapy on postoperative day 1. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23164.

The Role of Lumbar Drains in the Perioperative Management of Primary Spontaneous Temporal Lobe Encephaloceles and Cerebrospinal Fluid Leaks.

OBJECTIVE: To examine the role of lumbar drains (LDs) in the success of spontaneous temporal cerebrospinal fluid (CSF) leak and encephalocele repair. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic health system. PATIENTS: Patients undergoing repair of spontaneous temporal lobe encephaloceles or middle fossa CSF leaks during years 2017 to 2023. INTERVENTIONS: Transmastoid, middle fossa craniotomy, or combination approaches to CSF leak repair. OUTCOME MEASURES: Failure rate, complication rate, length of stay (LOS), readmission. RESULTS: Sixty-nine patients were included, with a combination approach performed in 78.3%, transmastoid in 17.4%, and isolated middle fossa craniotomy in 4.3%. Mean body mass index was 33.2, mean bony defect size width was 6.51 mm, and defect locations included the epitympanum, antrum, mastoid, and petrous apex. Multilayer closure with three or more layers was performed in 87.0%. LD was used in 73.9% of cases for a mean duration 2.27 days and was associated with longer LOS (3.27 vs. 1.56 d, p = 0.006) but not with failure rate, complications, discharge destination, or readmission. Only one major complication occurred as a result of the drain, but low-pressure headache was anecdotally common. CONCLUSIONS: Use of LD in the repair of spontaneous CSF leaks and temporal lobe encephaloceles is associated with longer LOS but not failure rates or other admission-level outcomes.

Prognosis Individualized: Survival predictions for WHO grade II and III gliomas with a machine learning-based web application.

WHO grade II and III gliomas demonstrate diverse biological behaviors resulting in variable survival outcomes. In the context of glioma prognosis, machine learning (ML) approaches could facilitate the navigation through the maze of factors influencing survival, aiding clinicians in generating more precise and personalized survival predictions. Here we report the utilization of ML models in predicting survival at 12, 24, 36, and 60 months following grade II and III glioma diagnosis. From the National Cancer Database, we analyze 10,001 WHO grade II and 11,456 grade III cranial gliomas. Using the area under the receiver operating characteristic (AUROC) values, we deploy the top-performing models in a web application for individualized predictions. SHapley Additive exPlanations (SHAP) enhance the interpretability of the models. Top-performing predictive models are the ones built with LightGBM and Random Forest algorithms. For grade II gliomas, the models yield AUROC values ranging from 0.813 to 0.896 for predicting mortality across different timeframes, and for grade III gliomas, the models yield AUROCs ranging from 0.855 to 0.878. ML models provide individualized survival forecasts for grade II and III glioma patients across multiple clinically relevant time points. The user-friendly web application represents a pioneering digital tool to potentially integrate predictive analytics into neuro-oncology clinical practice, to empower prognostication and personalize clinical decision-making.

Breaking boundaries through Doctors Reaching Minority Men Exploring Neuroscience: a mentorship model to foster a pipeline for underrepresented minorities.

OBJECTIVE: In 2015, the Association of American Medical Colleges report titled "Altering the Course: Black Males in Medicine" showed a decline in the number of Black men matriculating into medical school. To alter this trend, the authors' hypothesis was that formally exposing Black men to the clinical neurosciences during high school would enhance their chances of entering the physician workforce. For this reason, in 2007, the Doctors Reaching Minority Men Exploring Neuroscience (DR. MMEN) program was established at the Icahn School of Medicine at Mount Sinai. The program aimed to provide early exposure, mentorship, and inspiration to high school-age Black and Latinx men. The aim of this study was to evaluate the impact of the DR. MMEN program in the context of the recent race and ethnicity trends among medical school matriculants (MSMs). METHODS: Association of American Medical Colleges data on MSMs stratified by race and ethnicity were reviewed for the period between 2015 and 2020. Data pertinent to the academic achievements of DR. MMEN participants, such as matriculation to college and/or medical school, were prospectively tracked and incorporated with mixed-methods exit assessment data. Qualitative responses were coded and analyzed using a thematic concept analysis method. RESULTS: Over the study period, the increase of MSMs in the US was 1.0% and 1.7% for Black and Latinx individuals, respectively. Changes for the male MSM cohort were negligible: 0.3% for Black and 0.7% for Latinx. With respect to DR. MMEN, 42% of participants from 2017 to 2019 earned college scholarships, and 25% of students from the 2017-2018 cohort matriculated to a combined college-medical program. Survey data showed that 100% of DR. MMEN participants found the program useful. Analysis of qualitative data revealed that participants considered pursuing a career in neurosurgery or in another medical field. Diligence and a passion for medicine were identified as the top two most important lessons in the program, and witnessing patient satisfaction and observing a neurosurgery operation were described as the most important experiences. Participants considered availability to give advice and feedback and a passion for teaching as the principal attributes of their mentors. CONCLUSIONS: Over the past 6 years, the slight increase in Black and Latinx MSMs has not been significant enough to remedy ethnoracial disparities among MSMs. In particular, Black male matriculation to medical school has remained stagnant. The DR. MMEN program is a promising model to inspire young scholars and improve diversity within neuroscience and medicine at large.

The Impact of Obstructive Sleep Apnea on Clinical, Perioperative, and Cost Outcomes in Patients Who Underwent Posterior Cervical Decompression and Fusion: A Single-Center Retrospective Analysis From 2008 to 2016.

BACKGROUND: Obstructive sleep apnea (OSA) is a pervasive problem that can result in diminished neurocognitive performance, increased risk of all-cause mortality, and significant cardiovascular disease. While previous studies have examined risk factors that influence outcomes following cervical fusion procedures, to our knowledge, no study has examined the cost or outcome profiles for posterior cervical decompression and fusion (PCDF) procedures in patients with OSA. METHODS: All cases at a single institution between 2008 and 2016 involving a PCDF were included. The primary outcome was prolonged extubation, defined as an extubation that took place outside of the operating room. Secondary outcomes included admission to the intensive care unit (ICU), complications, extended hospitalization, nonhome discharge, readmission within 30 and 90 days, emergency room visit within 30 and 90 days, and higher total costs. RESULTS: We reviewed 1191 PCDF cases, of which 93 patients (7.81%) had a history of OSA. At the univariate level, patients with OSA had higher rates of ICU admissions (33.3% vs 16.8%, P < 0.0001), total complications (29.0% vs 19.0%, P = 0.0202), and respiratory complications (12.9% vs 6.6%, P = 0.0217). Multivariate regression analyses revealed no difference in the odds of a prolonged extubation (P = 0.4773) and showed that history of OSA was not predictive of higher costs. However, a significant difference was observed in the odds of having an ICU admission (P = 0.0046). CONCLUSION: While patients with sleep apnea may be more likely to be admitted to the ICU postoperatively, OSA status a lone is not a risk factor for poor primary and secondary clinical outcomes following posterior cervical fusion procedures. CLINICAL RELEVANCE: Various deformities of the cervical spine can exert extraluminal forces that partially collapse or obstruct the airway, thereby predisposing patients to OSA; however, no study has examined the cost or outcome profiles for PCDF procedures in patients with OSA. Therefore, this investigation highlights the ways in which OSA influences the risks, outcomes, and costs following PCDF using medical data from an institutional registry.

Intracranial extramedullary hematopoiesis in a patient with beta-thalassemia presenting with head trauma.

Background: Beta-thalassemia is an inherited hemoglobinopathy, whereby reduced or absent expression of beta-globin genes causes impaired erythropoiesis. Extramedullary hematopoiesis (EMH) occurs in 1% of all patients with beta-thalassemia major receiving regular transfusions and is exceedingly rare intracranially. Case Description: We report a case of a male in his 20s with beta thalassemia who presented with head trauma found to have intracranial EMH mimicking multiple extra-axial hematomas. Making the correct diagnosis was critical in avoiding prolonged neuromonitoring and unnecessary interventions. Conclusion: Intracranial extramedullary hematopoietic pseudotumor is an exceedingly rare entity and seldom appears in a neurosurgeon's differential diagnosis. This case illustrates how this condition can easily mimic an acute intracranial hemorrhage in a patient with beta-thalassemia who presents with head trauma. We review the topic to further inform clinicians who may encounter this condition in their practice.

Racial and Ethnical Diversity Within the Neurosurgery Resident and Faculty Workforce in the United States.

BACKGROUND: Promoting workplace diversity leads to a variety of benefits related to a broader range of perspectives and insights. Underrepresented in medicine (URiM), including African Americans, Latinx, and Natives (Americans/Alaskan/Hawaiians/Pacific Islanders), are currently accounting for approximately 40% of the US population. OBJECTIVE: To establish a snapshot of current URiM representation within academic neurosurgery (NS) programs and trends within NS residency. METHODS: All 115 NS residencies and academic programs accredited by the Accreditation Council for Graduate Medical Education in 2020 were included in this study. The National Residency Matching Program database was reviewed from 2011 to 2020 to analyze URiM representation trends over time within the NS resident workforce. The academic rank, academic and clinical title(s), subspecialty, sex, and race of URiM NS faculty (NSF) were obtained from publicly available data. RESULTS: The Black and Latinx NS resident workforce currently accounts for 4.8% and 5.8% of the total workforce, respectively. URiM NSF are present in 71% of the Accreditation Council for Graduate Medical Education-accredited NS programs and account for 8% (148 of 1776) of the workforce. Black and Latinx women comprise 10% of URiM NSF. Latinx NSFs are the majority within the URiM cohort for both men and women. URiM comprise 5% of all department chairs. All are men. Spine (26%), tumor (26%), and trauma (17%) were the top 3 subspecialties among URiM NSF. CONCLUSION: NS has evolved, expanded, and diversified in numerous directions, including race and gender representation. Our data show that ample opportunities remain to improve URiM representation within NS.

Valproic acid ameliorates C. elegans dopaminergic neurodegeneration with implications for ERK-MAPK signaling.

Parkinson's disease (PD) is a currently incurable neurodegenerative disorder that affects the aging population. The loss of dopaminergic neurons in the substantia nigra is one of the pathological features of PD. The precise causes of PD remain unresolved but evidence supports both environmental and genetic contributions. Current efforts for the treatment of PD are directed toward the discovery of compounds that show promise in impeding age-dependent neurodegeneration in PD patients. Alpha-synuclein (α-Syn) is a human protein that is mutated in specific populations of patients with familial PD. Overexpression of α-Syn in animal models of PD replicates key symptoms of PD, including neurodegeneration. Here, we use the nematode Caenorhabditis elegans as a model system, whereby α-Syn toxicity causes dopaminergic neurodegeneration, to test the capacity of valproic acid (VA) to protect neurons. The results of our study showed that treatment of nematodes with moderate concentrations of VA significantly protects dopaminergic neurons against α-Syn toxicity. Consistent with previously established knowledge related to the mechanistic action of VA in the cell, we showed through genetic analysis that the neuroprotection conferred by VA is inhibited by cell-specific depletion of the C. elegans ortholog of the MAP extracellular signal-regulated kinase (ERK), MPK-1, in the dopaminergic neurons. These findings suggest that VA may exert its neuroprotective effect via ERK-MAPK, or alternately could act with MAPK signaling to additively provide dopaminergic neuroprotection.