Machine learning models on a web application to predict short-term postoperative outcomes following anterior cervical discectomy and fusion.

BACKGROUND: The frequency of anterior cervical discectomy and fusion (ACDF) has increased up to 400% since 2011, underscoring the need to preoperatively anticipate adverse postoperative outcomes given the procedure's expanding use. Our study aims to accomplish two goals: firstly, to develop a suite of explainable machine learning (ML) models capable of predicting adverse postoperative outcomes following ACDF surgery, and secondly, to embed these models in a user-friendly web application, demonstrating their potential utility. METHODS: We utilized data from the National Surgical Quality Improvement Program database to identify patients who underwent ACDF surgery. The outcomes of interest were four short-term postoperative adverse outcomes: prolonged length of stay (LOS), non-home discharges, 30-day readmissions, and major complications. We utilized five ML algorithms - TabPFN, TabNET, XGBoost, LightGBM, and Random Forest - coupled with the Optuna optimization library for hyperparameter tuning. To bolster the interpretability of our models, we employed SHapley Additive exPlanations (SHAP) for evaluating predictor variables' relative importance and used partial dependence plots to illustrate the impact of individual variables on the predictions generated by our top-performing models. We visualized model performance using receiver operating characteristic (ROC) curves and precision-recall curves (PRC). Quantitative metrics calculated were the area under the ROC curve (AUROC), balanced accuracy, weighted area under the PRC (AUPRC), weighted precision, and weighted recall. Models with the highest AUROC values were selected for inclusion in a web application. RESULTS: The analysis included 57,760 patients for prolonged LOS [11.1% with prolonged LOS], 57,780 for non-home discharges [3.3% non-home discharges], 57,790 for 30-day readmissions [2.9% readmitted], and 57,800 for major complications [1.4% with major complications]. The top-performing models, which were the ones built with the Random Forest algorithm, yielded mean AUROCs of 0.776, 0.846, 0.775, and 0.747 for predicting prolonged LOS, non-home discharges, readmissions, and complications, respectively. CONCLUSIONS: Our study employs advanced ML methodologies to enhance the prediction of adverse postoperative outcomes following ACDF. We designed an accessible web application to integrate these models into clinical practice. Our findings affirm that ML tools serve as vital supplements in risk stratification, facilitating the prediction of diverse outcomes and enhancing patient counseling for ACDF.

An Interpretable Machine Learning Approach to Predict Survival Outcomes in Spinal and Sacropelvic Chordomas.

STUDY DESIGN: Retrospective, population-based cohort study. OBJECTIVE: This study aimed to develop machine learning (ML) models to predict five-year and 10-year mortality in spinal and sacropelvic chordoma patients and integrate them into a web application for enhanced prognostication. SUMMARY OF BACKGROUND DATA: Past research has uncovered factors influencing survival in spinal chordoma patients. While identifying individual predictors is important, personalized survival predictions are equally vital. Though prior efforts have resulted in nomograms aiming to serve this purpose, they cannot capture complex interactions within data and rely on statistical assumptions that may not fit real-world data. METHODS: Adult spinal and sacropelvic chordoma patients were identified from the National Cancer Database. Sociodemographic, clinicopathologic, diagnostic, and treatment-related variables were utilized as predictive features. Five supervised ML algorithms (TabPFN, CatBoost, XGBoost, LightGBM, and Random Forest) were implemented to predict mortality at five and 10 years postdiagnosis. Model performance was primarily evaluated using the area under the receiver operating characteristic (AUROC). SHapley Additive exPlanations (SHAP) values and partial dependence plots provided feature importance and interpretability. The top models were integrated into a web application. RESULTS: From the NCDB, 1206 adult patients diagnosed with histologically confirmed spinal and sacropelvic chordomas were retrieved for the five-year mortality outcome [423 (35.1%) with five-year mortality] and 801 patients for the 10-year mortality outcome [588 (73.4%) with 10-year mortality]. Top-performing models for both of the outcomes were the models created with the CatBoost algorithm. The CatBoost model for five-year mortality predictions displayed a mean AUROC of 0.801, and the CatBoost model predicting 10-year mortality yielded a mean AUROC of 0.814. CONCLUSIONS: This study developed ML models that can accurately predict five-year to 10-year survival probabilities in spinal chordoma patients. Integrating these interpretable, personalized prognostic models into a web application provides quantitative survival estimates for a given patient. The local interpretability enables transparency into how predictions are influenced. Further external validation is warranted to support generalizability and clinical utility.

Ultra-Early (<5 Hours) Decompression for Thoracolumbar Spinal Cord Injury: A Case Series.

Early surgical decompression within 24 hours for traumatic spinal cord injury (SCI) is associated with improved neurological recovery. However, the ideal timing of decompression is still up for debate. The objective of this study was to utilize our retrospective single-institution series of ultra-early (<5 hours) decompression to determine if ultra-early decompression led to improved neurological outcomes and was a feasible target over previously defined early decompression targets. Retrospective data on patients with SCI who underwent ultra-early (<5 hours) decompression at a level one metropolitan trauma center were extracted and collected from 2015-2018. American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade improvement was the primary outcome, with ASIA Motor score improvement and complication rate as secondary outcomes. Four individuals met the criteria for inclusion in this case series. All four suffered thoracolumbar SCI. All patients improved neurologically by AIS grade, and there were no complications directly related to ultra-early surgery. Given the small sample size, there was no statistically significant difference in outcomes compared to a control group who underwent early (5-24 hour) decompression in the same period. Ultra-early decompression is a feasible and safe target for thoracolumbar SCI and may lead to improved neurological outcomes without increased risk of complications. This case series can help create the foundation for future, larger studies that may definitively show the benefit of ultra-early decompression.

Complications of Implanted Vagus Nerve Stimulation: A Systematic Review and Meta-analysis.

INTRODUCTION: Vagus Nerve Stimulation (VNS) has emerged as a promising tool in ischemic stroke rehabilitation. However, there has been no systematic review summarizing its adverse effects, critical information for patients and providers when obtaining informed consent for this novel treatment. This systematic review and meta-analysis reports the adverse effects of VNS. METHODS: A systematic review was performed in accordance with PRISMA guidelines to identify common complications after VNS therapy. The search was executed in: Cochrane Central Register of Controlled Trials, Embase, and Ovid MEDLINE. All prospective, randomized controlled trials using implanted VNS therapy in adult patients were eligible for inclusion. Case studies and studies lacking complete complication reports were excluded. Extracted data included technology name, location of implantation, follow-up duration, purpose of VNS, and adverse event rates. RESULTS: After title-and-abstract screening of 4933 studies, 21 were selected for final inclusion. Across these studies, 1474 patients received VNS implantation. VNS was used as a potential therapy for epilepsy (9), depression (8), anxiety (1), ischemic stroke (1), chronic heart failure (1), and fibromyalgia (1). The 5 most common post-implant adverse events were voice alteration/hoarseness (n=671, 45.5%), paresthesia (n = 233, 15.8%), cough (n = 221, 15.0%), dyspnea (n = 211, 14.3%), and pain (n = 170, 11.5%). CONCLUSIONS: Complications from VNS are mild and transient, with reduction in severity and number of adverse events with increasing follow-up time. In prior studies, VNS has served as treatment option in several instances of treatment-resistant conditions, such as epilepsy and psychiatric conditions, and its use in stroke recovery and rehabilitation should continue to be explored.

Development and internal validation of machine learning models for personalized survival predictions in spinal cord glioma patients.

BACKGROUND CONTEXT: Numerous factors have been associated with the survival outcomes in patients with spinal cord gliomas (SCG). Recognizing these specific determinants is crucial, yet it is also vital to establish a reliable and precise prognostic model for estimating individual survival outcomes. OBJECTIVE: The objectives of this study are twofold: first, to create an array of interpretable machine learning (ML) models developed for predicting survival outcomes among SCG patients; and second, to integrate these models into an easily navigable online calculator to showcase their prospective clinical applicability. STUDY DESIGN: This was a retrospective, population-based cohort study aiming to predict the outcomes of interest, which were binary categorical variables, in SCG patients with ML models. PATIENT SAMPLE: The National Cancer Database (NCDB) was utilized to identify adults aged 18 years or older who were diagnosed with histologically confirmed SCGs between 2010 and 2019. OUTCOME MEASURES: The outcomes of interest were survival outcomes at three specific time points postdiagnosis: 1, 3, and 5 years. These outcomes were formed by combining the "Vital Status" and "Last Contact or Death (Months from Diagnosis)" variables. Model performance was evaluated visually and numerically. The visual evaluation utilized receiver operating characteristic (ROC) curves, precision-recall curves (PRCs), and calibration curves. The numerical evaluation involved metrics such as sensitivity, specificity, accuracy, area under the PRC (AUPRC), area under the ROC curve (AUROC), and Brier Score. METHODS: We employed five ML algorithms-TabPFN, CatBoost, XGBoost, LightGBM, and Random Forest-along with the Optuna library for hyperparameter optimization. The models that yielded the highest AUROC values were chosen for integration into the online calculator. To enhance the explicability of our models, we utilized SHapley Additive exPlanations (SHAP) for assessing the relative significance of predictor variables and incorporated partial dependence plots (PDPs) to delineate the influence of singular variables on the predictions made by the top performing models. RESULTS: For the 1-year survival analysis, 4,913 patients [5.6% with 1-year mortality]; for the 3-year survival analysis, 4,027 patients (11.5% with 3-year mortality]; and for the 5-year survival analysis, 2,854 patients (20.4% with 5-year mortality) were included. The top models achieved AUROCs of 0.938 for 1-year mortality (TabPFN), 0.907 for 3-year mortality (LightGBM), and 0.902 for 5-year mortality (Random Forest). Global SHAP analyses across survival outcomes at different time points identified histology, tumor grade, age, surgery, radiotherapy, and tumor size as the most significant predictor variables for the top-performing models. CONCLUSIONS: This study demonstrates ML techniques can develop highly accurate prognostic models for SCG patients with excellent discriminatory ability. The interactive online calculator provides a tool for assessment by physicians (https://huggingface.co/spaces/MSHS-Neurosurgery-Research/NCDB-SCG). Local interpretability informs prediction influences for a given individual. External validation across diverse datasets could further substantiate potential utility and generalizability. This robust, interpretable methodology aligns with the goals of precision medicine, establishing a foundation for continued research leveraging ML's predictive power to enhance patient counseling.

Ultra-early (≤8 hours) surgery for thoracolumbar spinal cord injuries: A systematic review and meta-analysis.

Background: The impact of the timing of surgery on neurological recovery in thoracolumbar spinal cord injuries (tSCI) is still a subject of discussion. Accumulating evidence is supporting early decompression (<24 hours) following tSCI. However, the potential advantages of earlier decompression remain uncertain. This systematic review and meta-analysis summarize and analyze the current evidence on the effectiveness of ultra-early decompression surgery on clinical outcomes following tSCI. Methods: A search was conducted in the electronic databases Medline, Embase, Scopus, and Web of Science from their inception until May 2022 for human studies. Groups were stratified into ultra-early (surgery within 8 hours of injury) vs control group operated >8 hours of injury. The authors included the study data from their institutional case series of thoracolumbar spinal cord injury from 2015 to 2018. An arm-based meta-analysis was performed on all studies using the R Studio. For studies that qualified, a contrast-based meta-analysis was also performed with a standardized mean difference (SMD). Outcomes were reported as effect size, treatment effect, and effect difference, all with 95% confidence intervals (CI). Results: Of the 133 patients, 74.4% patients were male. 76 (57.1%) underwent decompression ≤8 hours, while 57 (42.9%) underwent decompression >8 hours from injury. Quantitative analysis using the SMD model showed a significant difference in mean AIS improvement in the ultra-early group (Effect size 1.15 [0.62-1.67], p<.0001). On arm-based meta-analysis, a statistically significant treatment effect was found for the ultra-early arm (1.25 [0.91-1.67]), while > 8-hour arm did not show significance (0.30 [-0.08-0.71]). There was a statistically significant effect difference between the two arms (0.96 [0.49-1.48]). Conclusions: This study observed a significant improvement in the mean AIS score in patients undergoing decompression within 8 hours of tSCI. Given the scant literature regarding ultra-early decompression of tSCI, this study solidifies the need to further explore the role of early interventions for tSCIs to improve patient outcomes.

Exosome-Based Therapy for Ischemic Stroke: A Bibliometric Analysis of Current Trends and Future Directions.

BACKGROUND: Stroke is a leading cause of mortality and disability worldwide. Exosomes, or small extracellular vesicles with signaling properties, have recently been identified as novel mechanisms for stroke treatment. This study aims to use bibliometric techniques to identify current research trends and future directions of exosome-based stroke therapy. METHODS: The Web of Science Core Collection was searched using terms that included "exosome" and all stroke types. Bibliometric data, including authors, publication years, citations, countries/regions, institutions, journals, and Keywords Plus, were extracted directly from the Web of Science Core Collection. Keywords were mapped using VOSviewer. RESULTS: From 2010 to 2021, 424 documents were identified with a total of 12,708 citations. The number of publications increased yearly from 2012 to 2021, the majority of which were research and review articles. China and the United States produced the most publications with Henry Ford Hospital and Oakland University serving as the 2 most highly published research institutions. Documents were published most frequently in the journal Stroke. Keywords Plus analyses revealed 3 main research areas: exosomes as pathogenic mediators, biomarkers, and treatments of stroke. Ischemic stroke was the most prevalent type of stroke included in these studies. CONCLUSIONS: Using bibliometric techniques, this study identified a current and growing interest in the research of exosomes in stroke, particularly in their pathogenic, biomarker, and potential minimally invasive therapeutic properties. Given the high prevalence of ischemic stroke in the current literature, further characterization of exosomes in other stroke types, such as intracerebral hemorrhage, emerges as a future direction for this field of research.

Exosomes in subarachnoid hemorrhage: A scoping review.

INTRODUCTION: Vasospasm is a common complication following subarachnoid hemorrhage (SAH), causing increased ischemia and tissue injury, and is implicated as a major risk factor for poor outcomes. The success of current treatments for vasospasm is limited, with limited efficacy and unclear clinical benefits. Exosomes, vesicles that carry small molecules such as miRNA, have been theorized as a potential vasospasm treatment. In this study, we aim to survey the current literature discussing the role of exosomes in the setting of SAH. METHODS: Following PRISMA guidelines, we performed a scoping review evaluating the role of exosomes in the treatment of SAH. The search was conducted using PubMed and Scopus, and all original research papers studying exosomal profiles of SAH research subjects or SAH therapy were eligible for inclusion. RESULTS: After screening and full text review, seven papers were selected for final inclusion. Of these, two studies analyzed the expression profile of endogenous exosomes after SAH. Four papers identified and characterized miRNA-based exosomal therapies to attenuate early brain injury (EBI) after SAH. One paper discussed the role of protein overexpression in exosome delivery of miRNA for EBI after SAH. Interestingly, all identified papers studying exosomal therapy demonstrated anti-apoptotic or anti-inflammatory effects of miRNA exosomes acting via the BDNF/TrkB/CREB or HDAC3/NF-κB pathways. CONCLUSION: Identified studies demonstrate potential neuroprotective benefits of miRNA-based exosomal treatment of EBI and SAH. Findings warrant further research investigating the anti-inflammatory and anti-apoptotic role of exosomal miRNA delivery in SAH models, specifically targeting the common pathway identified by the authors.

Size Matters: Rethinking of the Sizing Classification of Pituitary Adenomas Based on the Rates of Surgery: A Multi-institutional Retrospective Study of 29,651 Patients.

Objective Pituitary adenomas are historically classified into microadenoma or macroadenomas based on size less than or greater than/equal to 1c m. "Giant" adenomas describe tumors ≥4 cm. The aim of this study is to present an evidence-based approach to size classification based on national trends. Design The design involved is multi-institutional retrospective study. Participants A total of 29,651 patients were studied from National Cancer Institute's SEER program from 2004 to 2016 across the United States. Main Outcome Measures The main outcome measures include demographics, treatment characteristics, and overall survival in the population. Results At the 20-mm threshold, the likelihood of operation exceeds the likelihood of nonoperative management. Patients with adenoma size 1 to 19 mm had significantly longer overall survival compared with 20 to 50 mm (Log rank: p < 0.0001). No survival difference was found between size 20 to 29 mm and larger. There was no significant difference in the rate of surgery between 30 to 39 mm and 40 to 50 mm tumors( p = 0.5035). Surgery group had a higher overall survival compared with nonsurgically managed patients (Log rank: p < 0.0001). Conclusion Microadenoma has classically been used to describe pituitary tumors less than 1 cm, though no clinical significance of this threshold has been demonstrated. The current study suggests a size cut-off of 20 or 30 mm as more clinically relevant. Still, future studies are warranted to examine the significance of this classification by specific tumor type, and subclassified as appropriate. There is no difference in the rate of surgery or survival for adenomas between 30 and 50 mm, challenging the 4-mm cutoff threshold for "giant" adenoma.

Feasibility of Full Neuromuscular Blockade During Transcranial Motor Evoked Potential Monitoring of Neurosurgical Procedures.

BACKGROUND: Transcranial motor evoked potential (TcMEP) monitoring is conventionally performed during surgical procedures without or with minimal neuromuscular blockade (NMB) because of its potential interference with signal interpretation. However, full blockade offers increased anesthetic management options and facilitates surgery. Here, the feasibility of TcMEP interpretation was assessed during full NMB in adult neurosurgical patients. METHODS: Patients undergoing cervical or lumbar decompression received a rocuronium bolus producing 95% or greater blockade by qualitative train-of-four at the ulnar nerve. TcMEPs were recorded in bilateral thenar-hypothenar and abductor hallucis muscles. Adequacy of response for reliable signal interpretation was determined on the basis of repeatability and clarity, assessed by coefficient of variation and signal-to-noise ratio, respectively. RESULTS: All patients had at least 3 of 4 measurable TcMEP limb responses present during full NMB, and 70.8% of patients had measurable responses in all 4 limbs. In total, 82.2% of thenar-hypothenar responses and 62.8% of abductor hallucis responses were robust enough for reliable signal interpretation on the basis of clarity. In addition, 97.8% of thenar-hypothenar responses and 79.1% of abductor hallucis responses met the criteria for reliable signal interpretation on the basis of consistency. Patient demographics, medical comorbidities, and preoperative weakness were not predictive of absent responses during full NMB. CONCLUSIONS: TcMEP interpretation may be feasible under greater levels of NMB than previously considered, allowing for monitoring with greater degrees of muscle relaxation. Consideration for monitoring TcMEP during full NMB should be made on a case-by-case basis, and baseline responses without blockade may predict which patients will have adequate responses for interpretation.

Differentiation of Outcomes by Treatment Regimen and Histology in Central Nervous System Primary Embryonal Tumors.

BACKGROUND: Central nervous system (CNS) embryonal tumors are malignant neoplasms of undifferentiated embryonic cells that typically occur in the pediatric population. They are further divided into many subgroups by distinct histologic and genetic profiles. We present the largest study to date to identify differential survival outcomes within each subgroup by treatment regimen. METHODS: The SEER (Surveillance Epidemiology and End Results) database was queried from 1973 to 2015 for embryonal tumors of primary CNS origin (n = 3900). The effects of patient demographics, tumor characteristics, and treatment regimen were analyzed using a multivariate Cox proportional hazard model in CNS embryonal tumor subtypes divided into medulloblastoma, atypical teratoid/rhabdoid tumor, and primitive neuroectodermal tumor. RESULTS: No significant patient demographic factors were found to be associated with increased mortality. In all 3 CNS embryonal tumor subtypes, most monotherapy and combinatorial treatment paradigms showed a higher hazard ratio compared with gross total resection with adjuvant chemoradiotherapy (hazard ratio, 1.72-22.94; P < 0.05 for all). In a subgroup analysis of patients with medulloblastoma ≤3 years of age, patients who did not receive radiation showed lower survival probabilities at 1, 5, and 10 years (odds ratio [OR], 0.37, P < 0.0001; OR, 0.39, P < 0.0001; OR, 0.34, P < 0.0001, respectively). Kaplan-Meier analysis of medulloblastoma histologic subtypes showed that use of radiation imparted a higher survival probability in the desmoplastic/nodular medulloblastoma and medulloblastoma not otherwise specified groups (P < 0.001 for both). CONCLUSIONS: CNS embryonal tumors are highly malignant in all populations and the best survival is seen with aggressive combination therapies. Radiation therapy may have a role in prolonging survival in patients with medulloblastoma ≤3 years of age.

Pituitary germinomas: a multi-institutional study analyzing patient demographics and management patterns.

PURPOSE: Intracranial germinomas are exceedingly rare tumors found in the pineal and suprasellar regions. The extremely low incidence of pituitary germinoma has resulted in a significant gap in knowledge regarding its demographics, management, and treatment outcomes. We present the largest multicenter analysis of pituitary germinomas to date, focused on analyzing demographic and management patterns. METHODS: This study utilizes the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program (2004-2016) to study patients with a primary intracranial germinoma of the pituitary gland. We analyzed demographic information and management strategies among adult and pediatric populations and conducted a 20-year overall survival analysis using Kaplan-Meier curve for a descriptive evaluation of survival outcomes between age groups and treatment groups. RESULTS: 92 patients were included in the study, consisting of 58% pediatric patients and 42% adults, with overall 60% males. 82% patients received radiation as part of the treatment, with no significant difference between pediatric and adult groups. Chemotherapy was used significantly more in pediatrics (p = 0.0002) while surgery was significantly more common in adults (p = 0.0117). The most common treatment in pediatrics was radiation + chemotherapy (47%), while the most common treatment in adults was radiation + gross total resection + chemotherapy (23%) followed by radiation + gross total resection (19%). Younger age, radiotherapy, and chemotherapy were associated with increased 20-year survival on Kaplan-Meier curves. CONCLUSIONS: There exist significant differences in the management of pediatric and adult populations with pituitary germinomas. The low incidence of these tumors makes them challenging to study, but also highlights the importance of national cancer registries in amassing sufficient patient data from which to draw evidence-based conclusions.

Treatment and survival of primary intracranial germ cell tumors: a population-based study using SEER database.

INTRODUCTION: Primary intracranial germ cell tumors are rare neoplasms derived from gonadal cells. They are categorized as germinoma, non-germinomatous germ cell tumor (NGCCT), or teratoma, with the latter two sparking controversy regarding the role of different treatment strategies. We provide the largest multicenter analysis of treatment outcomes for iGCTs to date. METHODS: The Surveillance, Epidemiology, and End Result (SEER) database were used to record patient demographics, tumor, and treatment characteristics. Cox proportional hazards model and multiple comparisons for the Logrank test with Sidak correction was applied to compare the different treatment regimens and survival. RESULTS: 1043 iGCT cases were divided into three cohorts of Germinoma, Malignant Teratoma (MT), and NGGCT. The mean age was 17.7 years for germinoma, 9.5 years for MT, and 14.4 years for NGGCT groups. Males comprised 77% of overall patient population. For Germinomas, both biopsy (hazard ratio [HR] = 4.6) and resection (HR = 14.1) had significantly worse survival outcomes compared to solo radiation therapy, with no difference between radiation and chemotherapy. For MT, no treatment combination had significantly different survival outcomes compared to resection alone. For NGGCTs, resection + chemotherapy + radiotherapy (HR = 0.012) and resection + chemotherapy (HR = 0.0049) had significantly better survival compared to resection alone. CONCLUSION: In germinomas, radiotherapy alone had superior survival outcomes compared to biopsy and resection, but no change in survival when compared to chemotherapy alone. Addition of radiotherapy or chemotherapy did not improve survival in MTs when compared to resection alone. Adding chemotherapy in NGGCT patients undergoing resection improved survival compared to resection alone.

Pediatric tethered cord release: an epidemiological and postoperative complication analysis.

BACKGROUND: Tethered cord release (TCR) is a common procedure in pediatric neurosurgery. Despite a reputation for being relatively safe, the risk factors for postoperative complications are poorly understood. METHODS: In this study, the American College of Surgeons-National Surgical Quality Improvement Program Pediatric Database (ACS-NSQIP-P) was reviewed to identify the demographics, risk factors, and 30-day postoperative complications for tethered cord release using univariate and multivariate analysis. A detailed analysis of reasons for readmission and reoperation was also performed. RESULTS: Three thousand and six hundred eighty-two pediatric patients were studied. Males undergoing TCR were younger (5.6 vs. 6.1 years) and had a higher rate of pre-operative comorbidities but lower 30-day complication rate versus females. Patients who later developed complications were more likely to require a microscope intraoperatively, had longer operative times, and worse preoperative American Society of Anesthesiologists (ASA) class. CONCLUSIONS: Despite being a relatively safe procedure, TCR in the pediatric population carries a finite risk of complications. In this large, international database study, males were found to have a greater number of risk factors prior to TCR, while females exhibit a higher risk of developing postoperative complications. This paper provides a large sample size of multi institutional pediatric patients undergoing TCR and may serve as a contemporary "snapshot" for future studies.

Adult Spinal Arteriovenous Malformations: Natural History and a Multicenter Study of Short-Term Surgical Outcomes.

OBJECTIVE: Spinal arteriovenous malformations (SAVMs) are a very rare and complex spinal cord pathology that require high clinical acumen to diagnose and treat. Management includes both nonoperative and operative paradigms. A review of the literature yields a paucity of data regarding the surgical outcomes of SAVMs, with the majority of data limited to single-center outcomes and/or small sample sizes. The purpose of this study was to use a multi-institutional international database to study the natural history of SAVMs. METHODS: We used the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to select patients that underwent laminectomy for surgical excision of a SAVM between 2008 and 2017. RESULTS: The data from 196 patients were studied (65.8% male, 34.2% female). A majority of cases were in the thoracic region (53.6%), followed by thoracolumbar (31.6%) and cervical (14.8%) regions. The mean age was 57.4 years and 52.5% patients were graded ASA class 3-5 before the operation. The mean operation time was 215 minutes, with a significantly lower operative time for thoracic arteriovenous malformations (195.6 minutes) when compared with cervical (266.6 minutes) and thoracolumbar (223.7 minutes). The mean length of hospital stay was 6.4 days. Patients had a 6.6% readmission rate and a 4.6% reoperation rate within 30 days. CONCLUSIONS: This study presents the largest analysis of patients undergoing surgery for SAVMs and 30-day postoperative outcomes. Operative time differed based on SAVM location. The three most frequent complications (deep vein thrombosis, wound infection, and UTI) occurred at rates of 3.6% or less.

Primary Malignant Melanoma of the Brain: A Population-Based Study.

BACKGROUND: Primary melanocytic neoplasms of the central nervous system (CNS) are rare and account for 1% of all melanomas. This study used the Surveillance, Epidemiology, and End Results (SEER) database to evaluate the epidemiology of primary CNS melanoma and further characterize their treatment. METHODS: Data from the National Cancer Institute SEER program, collected from 1973-2015, were retrospectively analyzed. A total of 86 records of malignant melanoma cases with CNS as the primary site were identified, and 54 patients were studied based on the inclusion criteria. Demographic, tumor, and treatment regimen effectiveness were studied. RESULTS: A total of 54 patients were included in this study. Tumors were distributed evenly in size and localized primarily to the cerebral meninges and spinal cord. A total of 13% of patients underwent biopsy, 40.7% gross total resection (GTR), 7.4% subtotal resection (STR), 46.3% radiation therapy (RT), and 27.3% chemotherapy (CT) in a variety of treatment combinations. GTR alone and STR + RT resulted in increased disease-specific survival compared to biopsy alone, but no survival benefit was found with biopsy with RT and/or CT as well as STR alone. CONCLUSIONS: To our knowledge, this is the largest single database study completed for primary malignant melanoma of the CNS. The study identified the need for tumor resection for the proper treatment of these lesions, particularly GTR. GTR could be paired with adjuvant RT or RT + CT providing survival benefit as well. In cases when GTR is unable to be completed, STR + RT provides significant improvement in survival compared to biopsy alone.

Supratentorial and Infratentorial Approaches to Pineal Surgery: A Database Analysis.

Objectives Neoplasms involving the pineal gland are rare. When they do occur, tumor resection is anatomically challenging and is traditionally addressed by either a supratentorial or an infratentorial approach. To date, no large, multicenter studies have been performed that systematically analyze outcomes comparing these two approaches. This study aimed to evaluate outcomes for patients undergoing pineal neoplasm resection, comparing supratentorial and infratentorial approaches. Design Retrospective database review. Setting Multi-institutional database. Participants From 2005 to 2016, 60 patients were identified, with 13 undergoing a supratentorial approach and 47 undergoing an infratentorial approach. Main Outcome Measures Patient demographics, comorbidities, and 30-day postoperative outcomes were investigated using the American College of Surgeons National Surgical Quality Improvement Program database. Demographics, readmission, reoperation, and complication rates were analyzed and compared with previous studies. Results Patient demographics were similar between these two groups. The overall complication rates for the supratentorial and infratentorial approaches were 30.8 and 17%, respectively, and the difference was not statistically significant. The most common medical complications encountered were respiratory and hematological. Conclusion As the first multi-institutional database analysis of approaches to the pineal gland, this study provides an analysis of patient demographics, comorbidities, and postoperative complications. After controlling for preoperative risk factors and demographic characteristics, no statistically significant differences in postoperative outcomes were found between infratentorial and supratentorial approaches. The mean readmission, reoperation, and complication rates were found to be 2.1, 8.3, and 20%, respectively. The lack of significant difference between approaches suggests that clinical decision-making should depend upon anatomical considerations and physician preference, although the complications illustrated here may provide some preoperative guidance.

Mycobacterium fortuitum Meningitis: Approach to Lumboperitoneal Shunt Infection.

Mycobacterium fortuitum is a rare, opportunistic pathogen most frequently contracted through contact with a contaminated source. An immunocompetent 26-year-old female patient presented to our institution with an infected lumboperitoneal (LP) shunt presenting as continued nonhealing wounds. After multiple debridements, shunt revisions, and wound closure failures, infectious disease specialists were consulted. The wound cultures returned positive for M. fortuitum and the shunt was removed. Cerebrospinal fluid studies revealed significant pleocytosis with normal opening pressure, and the patient was diagnosed as having secondary meningitis. After shunt removal, the patient was treated with intravenous and oral antibiotics, resulting in infection resolution. Five months later, a new LP shunt was placed without infection recurrence. Although M. fortuitum was previously reported in neurosurgical patients with ventriculoperitoneal shunts, which are summarized here, to date this is the first case in the literature of M. fortuitum meningitis from an LP shunt. This case demonstrates the importance of clinicians considering uncommon and slow-growing pathogens, as well as consulting infectious disease specialists for patients with persistent, unexplained infections.