Scoping review on the state of racial disparities literature in the treatment of neurosurgical disease: a call for action.

OBJECTIVE: Racial disparities are ubiquitous across medicine in the US. This study aims to assess the evidence of racial disparities within neurosurgery and across its subspecialties, with a specific goal of quantifying the distribution of articles devoted to either identifying, understanding, or reducing disparities. METHODS: The authors searched the MEDLINE, EMBASE, and Scopus databases by using keywords to represent the concepts of neurosurgery, patients, racial disparities, and specific study types. Two independent reviewers screened the article titles and abstracts for relevance. A third reviewer resolved conflicts. Data were then extracted from the included articles and each article was categorized into one of three phases: identifying, understanding, or reducing disparities. This review was conducted in accordance with the PRISMA Extension for Scoping Reviews (PRISMA-ScR) guidelines. RESULTS: Three hundred seventy-one studies published between 1985 and 2023 were included. The distribution of racial disparities literature was not equally spread among specialties, with spine representing approximately 48.3% of the literature, followed by tumor (22.1%) and general neurosurgery (12.9%). Most studies were dedicated to identifying racial disparities (83.6%). The proportion of literature devoted to understanding and reducing disparities was much lower (15.1% and 1.3%, respectively). Black patients were the most negatively impacted racial/ethnic group in the review (63.3%). The Hispanic or Latino ethnic group was the second most negatively impacted (25.1%). The following categories-other outcomes (28.0%), the offering of treatment (21.6%), complications (18.6%), and survival (16.7%)-represented the most frequently measured outcomes. CONCLUSIONS: Although strides have been taken to identify racial disparities within neurosurgery, fewer studies have focused on understanding and reducing these disparities. The tremendous rise of literature within this domain but the relative paucity of solutions necessitates the study of targeted interventions to provide equitable care for all patients undergoing neurosurgical treatment.

Implication of nutritional status for adverse outcomes after surgery for metastatic spine tumors.

OBJECTIVE: Surgery for metastatic spinal tumors can have a substantial impact on patients' quality of life by alleviating pain, improving function, and correcting spinal instability when indicated. The decision to operate is difficult because many patients with cancer are frail. Studies have highlighted the importance of preoperative nutritional status assessments; however, little is known about which aspects of nutrition accurately inform clinical outcomes. This study investigates the interaction and prognostic importance of various nutritional and frailty measures in patients with spinal metastases. METHODS: A retrospective analysis of consecutive patients who underwent surgery for spinal metastases between 2014 and 2020 at the Massachusetts General Hospital was performed. Patients were stratified according to the New England Spinal Metastasis Score (NESMS). Frailty was assessed using the metastatic spinal tumor frailty index. Nutrition was assessed using the prognostic nutritional index (PNI), preoperative body mass index, albumin, albumin-to-globulin ratio, and platelet-to-lymphocyte ratio. Outcomes included postoperative survival and complication rates, with focus on wound-related complications. RESULTS: This study included 154 individuals (39% female; mean [SD] age 63.23 [13.14] years). NESMS 0 and NESMS 3 demonstrated the highest proportions of severely frail patients (56.2%) and nonfrail patients (16.1%), respectively. Patients with normal nutritional status (albumin-to-globulin ratio and PNI) had a better prognosis than those with poor nutritional status when stratified by NESMS. Multivariable regression adjusted for NESMS and frailty showed that a PNI > 40.4 was significantly associated with decreased odds of 90-day complications (OR 0.93, 95% CI 0.85-0.98). After accounting for age, sex, primary tumor pathology, physical function, nutritional status, and frailty, a preoperative nutrition consultation was associated with a decrease in postoperative wound-related complications (average marginal effect -5.00%; 95% CI -1.50% to -8.9%). CONCLUSIONS: The PNI was most predictive of complications and may be a key biomarker for risk stratification in the 90 days following surgery. Nutrition consultation was associated with a reduced risk of wound-related complications, attesting to the importance of this preoperative intervention. These findings suggest that nutrition plays an important role in the postsurgical course and should be considered when developing a treatment plan for spinal metastases.

Critically reading machine learning literature in neurosurgery: a reader's guide and checklist for appraising prediction models.

OBJECTIVE: Machine learning (ML) has become an increasingly popular tool for use in neurosurgical research. The number of publications and interest in the field have recently seen significant expansion in both quantity and complexity. However, this also places a commensurate burden on the general neurosurgical readership to appraise this literature and decide if these algorithms can be effectively translated into practice. To this end, the authors sought to review the burgeoning neurosurgical ML literature and to develop a checklist to help readers critically review and digest this work. METHODS: The authors performed a literature search of recent ML papers in the PubMed database with the terms "neurosurgery" AND "machine learning," with additional modifiers "trauma," "cancer," "pediatric," and "spine" also used to ensure a diverse selection of relevant papers within the field. Papers were reviewed for their ML methodology, including the formulation of the clinical problem, data acquisition, data preprocessing, model development, model validation, model performance, and model deployment. RESULTS: The resulting checklist consists of 14 key questions for critically appraising ML models and development techniques; these are organized according to their timing along the standard ML workflow. In addition, the authors provide an overview of the ML development process, as well as a review of key terms, models, and concepts referenced in the literature. CONCLUSIONS: ML is poised to become an increasingly important part of neurosurgical research and clinical care. The authors hope that dissemination of education on ML techniques will help neurosurgeons to critically review new research better and more effectively integrate this technology into their practices.

An expanded role for surgery in grade 3 1p/19q co-deleted oligodendroglioma.

Background: Grade 3 1p/19q co-deleted oligodendroglioma is an uncommon primary CNS tumor with a high rate of progression and recurrence. This study examines the benefit of surgery after progression and identifies predictors of survival. Methods: This is a single-institution retrospective cohort study of consecutive adult patients with anaplastic or grade 3 1p/19q co-deleted oligodendroglioma diagnosed between 2001 and 2020. Results: Eighty patients with 1p/19q co-deleted grade 3 oligodendroglioma were included. The median age was 47 years (interquartile range 38-56) and 38.8% were women. All patients underwent surgery, including gross total resection (GTR) for 26.3% of patients, subtotal resection (STR) for 70.0% of patients, and biopsy for 3.8% of patients. Forty-three cases (53.8%) progressed at a median of 5.6 years, and the median overall survival (OS) was 14.1 years. Among 43 cases of progression or recurrence, 21 (48.8%) underwent another resection. Patients who underwent a second operation had improved OS (P = .041) and survival after progression/recurrence (P = .012), but similar time to subsequent progression as patients who did not have repeat surgery (P = .50). Predictors of mortality at initial diagnosis included a preoperative Karnofsky Performance Status (KPS) under 80 (hazard ratio [HR] 5.4; 95% CI 1.5-19.2), an STR or biopsy rather than GTR (HR 4.1; 95% CI 1.2-14.2), and a persistent postoperative neurologic deficit (HR 4.0; 95% CI 1.2-14.1). Conclusions: Repeat surgery is associated with increased survival, but not time to subsequent progression for progressing or recurrent 1p/19q co-deleted grade 3 oligodendrogliomas recur. Mortality is associated with a preoperative KPS under 80, lack of GTR, and persistent postoperative neurologic deficits after the initial surgery.

Promoting diversity in neurosurgery through a virtual symposium.

OBJECTIVE: The rates of women and underrepresented racial and ethnic minority (UREM) students successfully matching into neurosurgical residency are extremely low and do not reflect the makeup of the general population. As of 2019, only 17.5% of neurosurgical residents in the United States were women, 4.95% were Black or African American, and 7.2% were Hispanic or Latinx. Earlier recruitment of UREM students will help to diversify the neurosurgical workforce. Therefore, the authors developed a virtual educational event for undergraduate students entitled "Future Leaders in Neurosurgery Symposium for Underrepresented Students'' (FLNSUS). The primary objectives of the FLNSUS were to expose attendees to 1) neurosurgeons from diverse gender, racial, and ethnic backgrounds; 2) neurosurgical research; 3) opportunities for neurosurgical mentorship; and 4) information about life as a neurosurgeon. The authors hypothesized that the FLNSUS would increase student self-confidence, provide exposure to the specialty, and reduce perceived barriers to a neurosurgical career. METHODS: To measure the change in participant perceptions of neurosurgery, pre- and postsymposium surveys were administered to attendees. Of the 269 participants who completed the presymposium survey, 250 participated in the virtual event and 124 completed the postsymposium survey. Paired pre- and postsurvey responses were used for analysis, yielding a response rate of 46%. To assess the impact of participant perceptions of neurosurgery as a field, pre- and postsurvey responses to questions were compared. The change in response was analyzed, and a nonparametric sign test was performed to check for significant differences. RESULTS: According to the sign test, applicants showed increased familiarity with the field (p < 0.001), increased confidence in their abilities to become neurosurgeons (p = 0.014), and increased exposure to neurosurgeons from diverse gender, racial, and ethnic backgrounds (p < 0.001 for all categories). CONCLUSIONS: These results reflect a significant improvement in student perceptions of neurosurgery and suggest that symposiums like the FLNSUS may promote further diversification of the field. The authors anticipate that events promoting diversity in neurosurgery will lead to a more equitable workforce that will ultimately translate to enhanced research productivity, cultural humility, and patient-centered care in neurosurgery.

Differences in Outcomes and Health Care Resource Utilization After Surgical Intervention for Metastatic Spinal Column Tumor in Safety-Net Hospitals.

STUDY DESIGN: Observational cohort study. OBJECTIVE: The aim of this study was to investigate the association between safety-net hospital (SNH) status and hospital length of stay (LOS), cost, and discharge disposition in patients undergoing surgery for metastatic spinal column tumors. SUMMARY OF BACKGROUND DATA: SNHs serve a high proportion of Medicaid and uninsured patients. However, few studies have assessed the effects of SNH status on outcomes after surgery for metastatic spinal column tumors. PATIENTS AND METHODS: This study was performed using the 2016-2019 Nationwide Inpatient Sample database. All adult patients undergoing metastatic spinal column tumor surgeries, identified using ICD-10-CM coding, were stratified by SNH status, defined as hospitals in the top quartile of Medicaid/uninsured coverage burden. Hospital characteristics, demographics, comorbidities, intraoperative variables, postoperative complications, and outcomes were assessed. Multivariable analyses identified independent predictors of prolonged LOS (>75th percentile of cohort), nonroutine discharge, and increased cost (>75th percentile of cohort). RESULTS: Of the 11,505 study patients, 24.0% (n = 2760) were treated at an SNH. Patients treated at SNHs were more likely to be Black-identifying, male, and lower income quartile. A significantly greater proportion of patients in the non-SNH (N-SNH) cohort experienced any postoperative complication [SNH: 965 (35.0%) vs . N-SNH: 3535 (40.4%), P = 0.021]. SNH patients had significantly longer LOS (SNH: 12.3 ± 11.3 d vs . N-SNH: 10.1 ± 9.5 d, P < 0.001), yet mean total costs (SNH: $58,804 ± 39,088 vs . N-SNH: $54,569 ± 36,781, P = 0.055) and nonroutine discharge rates [SNH: 1330 (48.2%) vs . N-SNH: 4230 (48.4%), P = 0.715) were similar. On multivariable analysis, SNH status was significantly associated with extended LOS [odds ratio (OR): 1.41, P = 0.009], but not nonroutine discharge disposition (OR: 0.97, P = 0.773) or increased cost (OR: 0.93, P = 0.655). CONCLUSIONS: Our study suggests that SNHs and N-SNHs provide largely similar care for patients undergoing metastatic spinal tumor surgeries. Patients treated at SNHs may have an increased risk of prolonged hospitalizations, but comorbidities and complications likely contribute greater to adverse outcomes than SNH status alone. LEVEL OF EVIDENCE: 3.

Can We Use Artificial Intelligence Cluster Analysis to Identify Patients with Metastatic Breast Cancer to the Spine at Highest Risk of Postoperative Adverse Events?

OBJECTIVE: Group patients who required open surgery for metastatic breast cancer to the spine by functional level and metastatic disease characteristics to identify factors that predispose to poor outcomes. METHODS: A retrospective analysis included patients managed at 2 tertiary referral centers from 2008 to 2020. The primary outcome was a 90-day adverse event. A 2-step unsupervised cluster analysis stratified patients into cohorts using function at presentation, preoperative spine radiation, structural instability, epidural spinal cord compression (ESCC), neural deficits, and tumor location/hormone status. Comparisons were performed using χ2 test and one-way analysis of variance. RESULTS: Five patient "clusters" were identified. High function (HIGH) had thoracic metastases and an Eastern Cooperative Oncology Group (ECOG) score of 1.0 ± 0.8. Low function/irradiated (LOW + RADS) had preoperative radiation and the lowest Karnofsky scores (56.0 ± 10.6). Estrogen receptor or progesterone receptor (ER/PR) positive patients had >90% estrogen/progesterone positivity and moderate Karnofsky scores (74.0 ± 11.5). Lumbar/noncompressive (NON-COMP) had the fewest patients with ESCC grade 2 or 3 epidural disease (42.1%, P < 0.001). Low function/neurologic deficits (LOW + NEURO) had ESCC grade 2 or 3 disease and neurologic deficits. Adverse event rates were 25.0% in the HIGH group, 73.3% in LOW + RADS, 24.0% in ER/PR, 31.6% in NON-COMP, and 60.0% in LOW + NEURO (P = 0.003). CONCLUSIONS: Function at presentation, tumor hormone signature, radiation history, and epidural compression delineated postoperative trajectory. We believe our results can aid in expectation management and the identification of at-risk patients who may merit closer surveillance following surgical intervention.

Assessment of Spinal Metastases Surgery Risk Stratification Tools in Breast Cancer by Molecular Subtype.

BACKGROUND: Breast cancer molecular features and modern therapies are not included in spine metastasis prediction algorithms. OBJECTIVE: To examine molecular differences and the impact of postoperative systemic therapy to improve prognosis prediction for spinal metastases surgery and aid surgical decision making. METHODS: This is a retrospective multi-institutional study of patients who underwent spine surgery for symptomatic breast cancer spine metastases from 2008 to 2021 at the Massachusetts General Hospital and Brigham and Women's Hospital. We studied overall survival, stratified by breast cancer molecular subtype, and calculated hazard ratios (HRs) adjusting for demographics, tumor characteristics, treatments, and laboratory values. We tested the performance of established models (Tokuhashi, Bauer, Skeletal Oncology Research Group, New England Spinal Metastases Score) to predict and compare all-cause. RESULTS: A total of 98 patients surgically treated for breast cancer spine metastases were identified (100% female sex; median age, 56 years [IQR, 36-84 years]). The 1-year probabilities of survival for hormone receptor positive, hormone receptor positive/human epidermal growth factor receptor 2+, human epidermal growth factor receptor 2+, and triple-negative breast cancer were 63% (45 of 71), 83% (10 of 12), 0% (0 of 3), and 12% (1 of 8), respectively ( P < .001). Patients with triple-negative breast cancer had a higher proportion of visceral metastases, brain metastases, and poor physical activity at baseline. Postoperative chemotherapy and endocrine therapy were associated with prolonged survival. The Skeletal Oncology Research Group prognostic model had the highest discrimination (area under the receiver operating characteristic, 0.77 [95% CI, 0.73-0.81]). The performance of all prognostic scores improved when preoperative molecular data and postoperative systemic treatment plans was considered. CONCLUSION: Spine metastases risk tools were able to predict prognosis at a significantly higher degree after accounting for molecular features which guide treatment response.

Evaluating frailty, mortality, and complications associated with metastatic spine tumor surgery using machine learning-derived body composition analysis.

OBJECTIVE: Cancer patients with spinal metastases may undergo surgery without clear assessments of prognosis, thereby impacting the optimal palliative strategy. Because the morbidity of surgery may adversely impact recovery and initiation of adjuvant therapies, evaluation of risk factors associated with mortality risk and complications is critical. Evaluation of body composition of cancer patients as a surrogate for frailty is an emerging area of study for improving preoperative risk stratification. METHODS: To examine the associations of muscle characteristics and adiposity with postoperative complications, length of stay, and mortality in patients with spinal metastases, the authors designed an observational study of 484 cancer patients who received surgical treatment for spinal metastases between 2010 and 2019. Sarcopenia, muscle radiodensity, visceral adiposity, and subcutaneous adiposity were assessed on routinely available 3-month preoperative CT images by using a validated deep learning methodology. The authors used k-means clustering analysis to identify patients with similar body composition characteristics. Regression models were used to examine the associations of sarcopenia, frailty, and clusters with the outcomes of interest. RESULTS: Of 484 patients enrolled, 303 had evaluable CT data on muscle and adiposity (mean age 62.00 ± 11.91 years; 57.8% male). The authors identified 2 clusters with significantly different body composition characteristics and mortality risks after spine metastases surgery. Patients in cluster 2 (high-risk cluster) had lower muscle mass index (mean ± SD 41.16 ± 7.99 vs 50.13 ± 10.45 cm2/m2), lower subcutaneous fat area (147.62 ± 57.80 vs 289.83 ± 109.31 cm2), lower visceral fat area (82.28 ± 48.96 vs 239.26 ± 98.40 cm2), higher muscle radiodensity (35.67 ± 9.94 vs 31.13 ± 9.07 Hounsfield units [HU]), and significantly higher risk of 1-year mortality (adjusted HR 1.45, 95% CI 1.05-2.01, p = 0.02) than individuals in cluster 1 (low-risk cluster). Decreased muscle mass, muscle radiodensity, and adiposity were not associated with a higher rate of complications after surgery. Prolonged length of stay (> 7 days) was associated with low muscle radiodensity (mean 30.87 vs 35.23 HU, 95% CI 1.98-6.73, p < 0.001). CONCLUSIONS: Body composition analysis shows promise for better risk stratification of patients with spinal metastases under consideration for surgery. Those with lower muscle mass and subcutaneous and visceral adiposity are at greater risk for inferior outcomes.

First treatment and retreatment of medically refractive trigeminal neuralgia by stereotactic radiosurgery versus microvascular decompression: a systematic review and Meta-analysis.

PURPOSE: Procedures to treat medically refractory trigeminal neuralgia (MRTN) include stereotactic radiosurgery (SRS) and microvascular decompression (MVD). The aim of this study was to compare outcomes of SRS versus MVD in the treatment of MRTN, with a subgroup focus on those being treated for the first time. METHODS: Search strategy was performed using the PRISMA guidelines for article identification, screening, eligibility and inclusion. Relevant articles were identified from six electronic databases from their inception to June 2017. These articles were screened against established criteria for inclusion into this study. Meta-analysis was conducted by pooling results with odds ratios and subgroup analysis. RESULTS: From 13 relevant studies identified, 683 patients treated by SRS were compared with 670 patients treated by MVD for MRTN. Overall, the significant findings were that compared to MVD, SRS was associated with lower rates of short-term (OR = 0.16; 95%CI = 0.11-0.22; p < .001) and long-term pain freedom (OR = 0.31; 95%CI = 0.22-0.44; p < .001), fewer postoperative complications (OR = 0.06; 95%CI = 0.02-0.16; p < .001), more facial numbness and dysesthesia (OR = 1.64; 95%CI = 1.08-2.49; p = .02), and more pain recurrence (OR = 2.28; 95%CI = 1.32-3.93; p = .003). These trends were all reflected in MRTN patients being treated for the first time. CONCLUSION: Both SRS and MVD alleviate pain in MRTN patients. MVD results in superior rates of short- and long-term pain relief, facial numbness and dysesthesia control, and less recurrence amongst those in whom pain freedom was achieved, at the cost of greater postoperative complications when compared to SRS. Although no significant difference was found in terms of the need for retreatment surgery, there was a trend towards less procedures favoring MVD. First treatment by either technique represents the overall trends reported.