Awake neurosurgery: Advancements in microvascular decompression for trigeminal neuralgia.

Background: The treatment landscape for trigeminal neuralgia (TN) involves various surgical interventions, among which microvascular decompression (MVD) stands out as highly effective. While MVD offers significant benefits, its success relies on precise surgical techniques and patient selection. In addition, the emergence of awake surgery techniques presents new opportunities to improve outcomes and minimize complications associated with MVD for TN. Methods: A thorough review of the literature was conducted to explore the effectiveness and challenges of MVD for TN, as well as the impact of awake surgery on its outcomes. PubMed and Medline databases were searched from inception to March 2024 using specific keywords "Awake Neurosurgery," "Microvascular Decompression," AND "Trigeminal Neuralgia." Studies reporting original research on human subjects or preclinical investigations were included in the study. Results: This review highlighted that MVD emerges as a highly effective treatment for TN, offering long-term pain relief with relatively low rates of recurrence and complications. Awake surgery techniques, including awake craniotomy, have revolutionized the approach to MVD, providing benefits such as reduced postoperative monitoring, shorter hospital stays, and improved neurological outcomes. Furthermore, awake MVD procedures offer opportunities for precise mapping and preservation of critical brain functions, enhancing surgical precision and patient outcomes. Conclusion: The integration of awake surgery techniques, particularly awake MVD, represents a significant advancement in the treatment of TN. Future research should focus on refining awake surgery techniques and exploring new approaches to optimize outcomes in MVD for TN.

Redefining cerebellar assessment: A comprehensive review of the cerebellum's cognitive and affective roles and the efficacy of CCAS scales.

Background: Emerging research expands our understanding of the cerebellum beyond motor control to include cognitive, emotional, and autonomic functions. This review examines the cerebellum's complex role, spotlighting Schmahmann's syndrome, or cerebellar cognitive affective syndrome (CCAS), which impairs executive functions, language, and spatial processing. It emphasizes advancements in diagnosing CCAS and the imperative of developing superior diagnostic tools for managing cerebellar pathologies effectively. Methods: A comprehensive literature search was performed using databases such as PubMed, OVID Embase, and OVID Medline. Using the keywords "cerebellar cognitive, affective syndrome" and "Schmahmann syndrome," the search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines for systemic review, in which the selection process narrowed down an initial set of 54 articles to 12, focusing on the impact of the CCAS scale on diagnosing and understanding Schmahmann's syndrome. Results: The review's analysis confirms the cerebellum's roles in motor and cognitive functions and underscores the CCAS scale as a significant advancement in detecting cerebellar deficits, surpassing traditional assessments such as the mini-mental state examination and Montreal cognitive assessment. Conclusion: This review emphasizes the importance of understanding the cerebellum's involvement in cognition and emotion and the crucial role of the CCAS scale for identifying cerebellar impairments. It calls for better diagnostic tools to assess CCAS accurately and suggests enhancing the CCAS Scale to reflect cultural and educational diversity. This will improve the diagnosis and treatment of cerebellar disorders, promoting a comprehensive neurological perspective on the cerebellum's functions.

Neuromodulation and the Gut-Brain Axis: Therapeutic Mechanisms and Implications for Gastrointestinal and Neurological Disorders.

The gut-brain axis (GBA) represents a complex, bidirectional communication network that intricately connects the gastrointestinal tract with the central nervous system (CNS). Understanding and intervening in this axis opens a pathway for therapeutic advancements for neurological and gastrointestinal diseases where the GBA has been proposed to play a role in the pathophysiology. In light of this, the current review assesses the effectiveness of neuromodulation techniques in treating neurological and gastrointestinal disorders by modulating the GBA, involving key elements such as gut microbiota, neurotrophic factors, and proinflammatory cytokines. Through a comprehensive literature review encompassing PubMed, Google Scholar, Web of Science, and the Cochrane Library, this research highlights the role played by the GBA in neurological and gastrointestinal diseases, in addition to the impact of neuromodulation on the management of these conditions which include both gastrointestinal (irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and gastroesophageal reflux disease (GERD)) and neurological disorders (Parkinson's disease (PD), Alzheimer's disease (AD), autism spectrum disorder (ASD), and neuropsychiatric disorders). Despite existing challenges, the ability of neuromodulation to adjust disrupted neural pathways, alleviate pain, and mitigate inflammation is significant in improving the quality of life for patients, thereby offering exciting prospects for future advancements in patient care.

Gene Expression Patterns Associated with Survival in Glioblastoma.

The aim of this study was to investigate gene expression alterations associated with overall survival (OS) in glioblastoma (GBM). Using the Nanostring nCounter platform, we identified four genes (COL1A2, IGFBP3, NGFR, and WIF1) that achieved statistical significance when comparing GBM with non-neoplastic brain tissue. The four genes were included in a multivariate Cox Proportional Hazard model, along with age, extent of resection, and O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation, to create a unique glioblastoma prognostic index (GPI). The GPI score inversely correlated with survival: patient with a high GPI had a median OS of 7.5 months (18-month OS = 9.7%) whereas patients with a low GPI had a median OS of 20.1 months (18-month OS = 54.5%; log rank p-value = 0.004). The GPI score was then validated in 188 GBM patients from The Cancer Genome Atlas (TCGA) from a national data base; similarly, patients with a high GPI had a median OS of 10.5 months (18-month OS = 12.4%) versus 16.9 months (18-month OS = 41.5%) for low GPI (log rank p-value = 0.0003). We conclude that this novel mRNA-based prognostic index could be useful in classifying GBM patients into risk groups and refine prognosis estimates to better inform treatment decisions or stratification into clinical trials.

Addressing healthcare disparities in homeless neurosurgical patients: A comprehensive literature review on strategies for equitable care and improved outcomes.

Background: Homelessness is a growing concern in the US, with 3.5 million people experiencing it annually and 600,000 on any given night. Homeless individuals face increased vulnerability to 30-day hospital readmissions and higher mortality rates, straining the healthcare system and exacerbating existing disparities. This study aims to inform neurosurgeons on evidence-based strategies to reduce readmission and mortality rates among homeless patients by reviewing the literature on the impact of medical respite on 30-day readmission rates. The study aims to gauge the efficacy of medical respite in reducing hospital readmissions and improving health outcomes for homeless individuals. Methods: A comprehensive literature search was conducted across PubMed, Embase/Medline, and Cochrane databases, as well as consulting the National Institute for Medical Respite Care and the Department of Health Care Access and Information. Ten articles were chosen from an initial 296 to investigate the impact of respite programs on readmission rates among homeless patients. Results: Homeless patients experience high readmission rates due to various factors. Interventions such as respite programs and a comprehensive approach to healthcare can lower these rates. Collaboration between hospitals and medical respites has proven particularly effective. Conclusion: Inadequate healthcare for homeless individuals leads to increased readmissions, longer hospital stays, and higher costs. Medical respites are a viable solution, but limited resources hamper their effectiveness. Therefore, it is crucial to facilitate cooperation between hospitals, respites, and other entities. Future research should focus on disparity in neurosurgical procedures and explore alternative services. An interdisciplinary approach is key to addressing healthcare inequalities.

Discontinuation of affirmative action: Consequences for black educational equity, neurosurgical residency, and medical diversity, with consideration of potential adversity as a new path forward.

Background: The underrepresentation of the Black community in neurosurgery is concerning, especially given projections that racial minorities will become the majority in the U.S. by 2044. Yet, despite these forecasts, Black candidates make up less than 4% of those in neurosurgical training programs. The recent Supreme Court decision to end Affirmative Action underscores the urgency of addressing this disparity. This research delves into the implications of eliminating Affirmative Action on neurosurgery admissions and residencies. Methods: A comprehensive literature search was performed using PubMed, OVID Embase, and OVID Medline, employing the keywords "Black", "Neurosurgery", and "Residency". The Maslow Adversity Index (MAI) was created to integrate adversity as a factor in neurosurgery residency evaluation. Results: After Affirmative Action, Black college enrollment increased, peaking at 36% by 2020. However, Black medical students remain underrepresented in neurosurgery residencies. ALDC (Athletes, Legacies, Dean's List, Children of faculty/staff) admissions criteria favor White students. Furthermore, studies have highlighted the beneficial impacts of racial concordance on patient outcomes. The end of Affirmative Action necessitates new diversity strategies in admissions. A points-based assessment, inspired by Maslow's hierarchy, recognizes adversities faced by underrepresented applicants which could help residency programs enhance diversity, inclusivity, and equity in selection. Conclusion: Despite the growth in Black college attendance, disparities persist in specialized medical fields like neurosurgery. The end to Affirmative Action policies might exacerbate these disparities. Embracing holistic admission approaches, rooted in Maslow's hierarchy. This consideration is key for inclusive representation, impacting education, professions, and health outcomes.

The importance of behavioral interventions in traumatic brain injury.

Background: Traumatic brain injury (TBI) poses a significant public health concern, profoundly impacting individuals and society. In this context, behavioral interventions have gained prominence as crucial elements in TBI management, addressing the diverse needs of TBI-affected individuals. Methods: A comprehensive literature search was conducted, utilizing databases such as PubMed, Embase, and Scopus. Inclusion criteria encompassed studies focusing on behavioral interventions in TBI, with a particular emphasis on their impact on outcomes. Relevant articles published within the past decade were prioritized, and a qualitative synthesis of the findings was performed. Results: Behavioral interventions have demonstrated their effectiveness in addressing various aspects of TBI care. They have been instrumental in improving cognitive functions, emotional stability, and adaptive behaviors among TBI patients. However, it is important to acknowledge that challenges still exist, including issues related to clinical heterogeneity and healthcare disparities. Conclusion: The integration of behavioral interventions into standard clinical practice marks a transformative shift in TBI care. This approach holds immense potential for enhancing patient outcomes and elevating the overall quality of life for individuals grappling with the complexities of this condition. This review serves as a clarion call for healthcare practitioners, researchers, and policymakers to recognize the pivotal role of behavioral interventions in TBI care, advocating for their wider adoption to advance the field toward a more holistic and patient-centric approach.

Neuroprotection strategies in traumatic brain injury: Studying the effectiveness of different clinical approaches.

Background: This review delves into clinical strategies aimed at addressing the complexities of traumatic brain injury (TBI), specifically focusing on pharmaceutical interventions and stem cell therapies as potential avenues for enhancing TBI outcomes. Methods: A thorough review of clinical strategies for TBI management, encompassing pharmaceutical and nonpharmaceutical interventions, was performed. PubMed, MEDLINE and clinical trial databases were searched to identify relevant studies and clinical trials. Inclusion criteria consisted of studies involving pharmaceutical agents and other clinical approaches (i.e., stem cell therapies) targeting neuroinflammation, excitotoxicity, oxidative stress, and neurodegeneration in TBI. Data from clinical trials and ongoing research initiatives were analyzed to assess the current status and potential of these clinical approaches. Results: Many trials have been conducted to face the challenge that is TBI. These interventions are designed to target critical aspects of secondary brain injury, encompassing neuroinflammation, excitotoxicity, oxidative stress, and neurodegeneration. Despite this, there is no panacea or definitive remedy for this condition. Combining therapies in a patient-tailored approach seems to be our best chance to improve these patients' outcomes, but systematic protocols are needed. Conclusion: Clinical strategies represent dynamic and continually evolving pathways in TBI management. This review provides an extensive overview of the existing landscape of clinical approaches and promising new studies and outlines their influence on patient outcomes. By highlighting challenges and presenting opportunities, it contributes to the ongoing mission to advance clinical care for individuals impacted by TBI.

Neuroprotection: Surgical approaches in traumatic brain injury.

Background: This review is centered on the pivotal role of surgical interventions within the comprehensive management of traumatic brain injury (TBI). Surgical strategies are indispensable components of TBI care, encompassing primary injury management and the alleviation of secondary injury processes, including the handling of intracranial hemorrhages (ICHs), contusions, and mass lesions. Methods: A systematic review was carried out by searching databases including PubMed, Embase, and Scopus. The inclusion criteria involved studies discussing surgical strategies for TBI, with a focus on primary injury management, ICHs, contusions, and mass lesions. More recent articles were prioritized, and data were synthesized to assess the impact of surgical interventions on TBI outcomes. Results: The evolution of surgical technologies has heralded a transformation in TBI management. These advancements encompass minimally invasive procedures, neuroimaging-guided surgeries, and robotic-assisted techniques, all geared toward optimizing patient outcomes. Conclusion: Surgical interventions within TBI care present unique challenges, such as timing considerations, patient selection criteria, and postoperative care. This review underscores the critical significance of multidisciplinary collaboration among neurosurgeons, neurologists, and critical care specialists. Such collaboration is essential to tailor surgical strategies to the individualized needs of patients. Moreover, the review highlights emerging trends in TBI surgery and underscores the ongoing imperative of research endeavors aimed at refining surgical protocols and ultimately enhancing patient outcomes.

Leukocyte differential gene expression prognostic value for high versus low seizure frequency in temporal lobe epilepsy.

BACKGROUND: This study was performed to test the hypothesis that systemic leukocyte gene expression has prognostic value differentiating low from high seizure frequency refractory temporal lobe epilepsy (TLE). METHODS: A consecutive series of patients with refractory temporal lobe epilepsy was studied. Based on a median baseline seizure frequency of 2.0 seizures per month, low versus high seizure frequency was defined as ≤ 2 seizures/month and > 2 seizures/month, respectively. Systemic leukocyte gene expression was analyzed for prognostic value for TLE seizure frequency. All differentially expressed genes were analyzed, with Ingenuity® Pathway Analysis (IPA®) and Reactome, to identify leukocyte gene expression and biological pathways with prognostic value for seizure frequency. RESULTS: There were ten males and six females with a mean age of 39.4 years (range: 16 to 62 years, standard error of mean: 3.6 years). There were five patients in the high and eleven patients in the low seizure frequency cohorts, respectively. Based on a threshold of twofold change (p < 0.001, FC > 2.0, FDR < 0.05) and expression within at least two pathways from both Reactome and Ingenuity® Pathway Analysis (IPA®), 13 differentially expressed leukocyte genes were identified which were all over-expressed in the low when compared to the high seizure frequency groups, including NCF2, HMOX1, RHOB, FCGR2A, PRKCD, RAC2, TLR1, CHP1, TNFRSF1A, IFNGR1, LYN, MYD88, and CASP1. Similar analysis identified four differentially expressed genes which were all over-expressed in the high when compared to the low seizure frequency groups, including AK1, F2R, GNB5, and TYMS. CONCLUSIONS: Low and high seizure frequency TLE are predicted by the respective upregulation and downregulation of specific leukocyte genes involved in canonical pathways of neuroinflammation, oxidative stress and lipid peroxidation, GABA (γ-aminobutyric acid) inhibition, and AMPA and NMDA receptor signaling. Furthermore, high seizure frequency-TLE is distinguished prognostically from low seizure frequency-TLE by differentially increased specific leukocyte gene expression involved in GABA inhibition and NMDA receptor signaling. High and low seizure frequency patients appear to represent two mechanistically different forms of temporal lobe epilepsy based on leukocyte gene expression.

Subdural hematoma, retinal hemorrhage, and fracture triad as a clinical predictor for the diagnosis of child abuse.

OBJECTIVE: Nonaccidental trauma (NAT) is a major cause of traumatic death during infancy and early childhood. Several findings are known to raise the index of clinical suspicion: subdural hematoma (SDH), retinal hemorrhage (RH), fracture, and external trauma. Combinations of certain injury types, determined via statistical frequency associations, may assist clinical diagnostic tools when child abuse is suspected. The present study sought to assess the statistical validity of the clinical triad (SDH + RH + fracture) in the diagnosis of child abuse and by extension pediatric NAT. METHODS: A retrospective review of The University of Arizona Trauma Database was performed. All patients were evaluated for the presence or absence of the components of the clinical triad according to specific International Classification of Diseases (ICD)-10 codes. Injury type combinations included some variation of SDH, RH, all fractures, noncranial fracture, and cranial fracture. Each injury type was then correlated with the ICD-10 codes for child abuse or injury comment keywords. Statistical analysis via contingency tables was then conducted for test characteristics such as sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS: There were 3149 patients younger than 18 years of age included in the quantitative analysis, all of whom had at least one component of the clinical triad. From these, 372 patients (11.8%) had a diagnosis of child abuse. When compared to a single diagnosis of either SDH, RH, all fractures, noncranial fracture, or cranial fracture, the clinical triad had a significantly greater correlation with the diagnosis of child abuse (100% of cases) (p < 0.0001). The dyad of SDH + RH also had a significantly greater correlation with a child abuse diagnosis compared to single diagnoses (88.9%) (p < 0.0001). The clinical triad of SDH + RH + fracture had a sensitivity of 88.8% (95% CI 87.6%-89.9%), specificity of 100% (95% CI 83.9%-100%), and positive predictive value of 100% (95% CI 99.9%-100%). The dyad of SDH + RH had a sensitivity of 89.1% (95% CI 87.9%-90.1%), specificity of 88.9% (95% CI 74.7%-95.6%), and positive predictive value of 99.9% (95% CI 99.6%-100%). All patients with the clinical triad were younger than 3 years of age. CONCLUSIONS: When SDH, RH, and fracture were present together, child abuse and by extension pediatric NAT were highly likely to have occurred.

Emotional intelligence in neurosurgery: Mitigating burnout and enhancing performance.

Background: This study underscores the high burnout rates among physicians, particularly surgical residents, attributing it to the demanding health-care ecosystem. It highlights the negative impacts of burnout, such as medical errors and increased health-care costs, while exploring the potential mitigating role of emotional intelligence (EI) and mindfulness. The research aimed to analyze the existing literature on EI in neurosurgery, focusing on its relationship with physician burnout and its potential role in healthcare leadership and residency training programs. Methods: A comprehensive literature review was conducted using multiple databases, including PubMed, OVID Embase, and OVID Medline, using the keywords "Emotional Intelligence" and "neurosurgery." The search duration spanned from each database's inception to June 2023. Results: The review highlighted various studies emphasizing the importance of integrating EI and mindfulness training into medical education and leadership, suggesting that a balance between technical competencies and interpersonal skills are critical. It identified personal integrity, effective communication, professional ethics, pursuit of excellence, relationship building, and critical thinking as key competencies for health-care leadership. Conclusion: EI and a growth mindset play a critical role in managing burnout, enhancing job satisfaction and performance, and promoting effective healthcare leadership. The review, however, acknowledges certain limitations such as small sample sizes, single-institution experiences, potential biases, and inconsistencies in burnout parameters and EI measurement tools. Despite these, it points toward potential areas for future investigation and highlights the importance of standardized EI measurement tools and robust quantitative assessment methods.

Outcomes following therapeutic intervention of post-traumatic vasospasm: A systematic review and meta-analysis.

BACKGROUND: Vasospasm occurrence following traumatic brain injury may impact neurologic and functional recovery of patients, yet treatment of post-traumatic vasospasm (PTV) has not been well documented. This systematic review and meta-analysis aims to assess the current evidence regarding favorable outcome as measured by Glasgow Outcome Scale (GOS) scores following treatment of PTV. METHODS: A systematic review of PubMed, Ovid MEDLINE, and Ovid EMBASE was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included manuscripts were methodically scrutinized for quality; occurrence of PTV; rate of favorable outcome following each treatment modality; and follow-up duration. Treatments evaluated were calcium channel blockers (CCBs), endovascular intervention, and dopamine-induced hypertension. Outcomes were compared via the random-effects analysis. RESULTS: Fourteen studies with 1885 PTV patients were quantitatively analyzed: 982 patients who received tailored therapeutic intervention and 903 patients who did not receive tailored therapy. For patients undergoing treatment, the rate of favorable outcome was 57.3 % (500/872 patients; 95 % CI 54.1 - 60.6 %) following administration of CCBs, 94.1 % (16/17 patients; 95 % CI 82.9 - 100.0 %) following endovascular intervention, and 54.8 % (51/93 patients; 95 % CI 44.7 - 65.0 %) following dopamine-induced hypertension. Of note, the endovascular group had the highest rate of favorable outcome but was also the smallest sample size (n = 17). Patients who received tailored therapeutic intervention for PTV had a higher rate of favorable outcome than patients who did not receive tailored therapy: 57.7 % (567/982 patients; 95 % CI 54.1 - 60.8 %) versus 52.0 % (470/903 patients; 95 % CI 48.8 - 55.3 %), respectively. CONCLUSIONS: The available data suggests that tailored therapeutic intervention of PTV results in a favorable outcome. While endovascular intervention of PTV had the highest rate of favorable outcome, both CCB administration and dopamine-induced hypertension had similar lower rates of favorable outcome.

Predictors of revision surgery after bedside subdural drain placement for chronic subdural hematomas.

BACKGROUND AND OBJECTIVE: For chronic subdural hematoma (cSDH), bedside subdural drains (SDD) provide a useful alternative to more invasive neurosurgical techniques, including evacuation through multiple burr holes or formal craniotomy. However, no scale currently exists adequately predicting SDD candidacy or treatment response. The present study sought to characterize predictors of revision surgery after initial treatment with bedside SDD for cSDH. METHODS: We conducted a retrospective case control study of cSDH patients treated with bedside SDD at a level one trauma center between 2018 and 2022. Binomial regression was used to compare SDD patients and generate odds ratios associated with revision surgery, which were compared using a binary random effects model. RESULTS: Ninety six cSDH patients were included, of whom 13 (13.5%) required a revision surgery after initial treatment failure with bedside SDD. Patients requiring revision surgery demonstrated an increased male predominance (84.6% vs. 69.9% of SDD patients not requiring revision surgery), tended to be younger (67.8 vs. 70.5 years) with a greater body mass index (28.7 vs. 25.6 kg/m2), and have a lower Glasgow Coma Scale (GCS) score on presentation of 12.5 (versus 14). Patients with an initial GCS score less than 13 (OR 11.0 95% CI 2.8 - 43.3), midline shift greater than 10 mm on CT (OR 6.5 95% CI 1.7 - 25.7), or duration of SDD placement longer than 3 days (OR 10.5 95% CI 2.6 - 41.9) demonstrated a greater likelihood of needing a revision surgery after initial treatment with bedside SDD. CONCLUSION: Among patients treated with SDD, we identified 3 independent factors predicting the need for revision surgery: GCS score, midline shift, and duration of drain placement. Craniotomy may be favored over bedside SDD in patients presenting with a GCS score less than 13 or midline shift greater than 10 mm and for SDD patients demonstrating inadequate clinical response after 3 days.

Spinal cord stimulation for genitofemoral neuropathy: A case report and review of the literature.

Background: Chronic testicular pain due to genitofemoral neuropathy often becomes refractory to conservative medical therapy. Neurostimulation is a potentially useful treatment option, should the neuropathic pain remain refractory to more invasive procedures such as orchiectomy. We provide a case report of spinal cord stimulation (SCS) for successful treatment of genitofemoral neuropathy and have also reviewed the literature to find similar cases which required a similar treatment paradigm. Case Description: A 42-year-old male underwent SCS for refractory testicular and groin pain. SCS through a four-column, 2 × 8 contact neurostimulator paddle lead, was implanted in the mid-thoracic-9 (T9) vertebral level, providing > 50% testicular pain relief with a decrease in visual analog scale scores from 8-10/10 to 3-4/10. The patient required one adjustment to the stimulation parameters at the time of the 6 weeks follow-up visit due to over-stimulation. He then continued to experience >50% resolution in pain 9 months later. A review of the literature yielded only two similar cases that successfully utilized SCS for treatment of chronic testicular pain. Conclusion: SCS should be considered as a possible treatment option for patients with chronic testicular pain localized to the genitofemoral nerve distribution.

Three-Dimensional Printing in Neurosurgery Residency Training: A Systematic Review of the Literature.

BACKGROUND: The use of three-dimensional (3D) printing in neurosurgery has become more prominent in recent years for surgical training, preoperative planning, and patient education. Several smaller studies are available using 3D printing; however, there is a lack of a concise review. This article provides a systematic review of 3D models in use by neurosurgical residents, with emphasis on training, learning, and simulation. METHODS: A structured literature search of PubMed and Embase was conducted using PRISMA guidelines to identify publications specific to 3D models trialed on neurosurgical residents. Criteria for eligibility included articles discussing only neurosurgery, 3D models in neurosurgery, and models specifically tested or trialed on residents. RESULTS: Overall, 40 articles were identified that met inclusion criteria. These studies encompassed different neurosurgical areas including aneurysm, spine, craniosynostosis, transsphenoidal, craniotomy, skull base, and tumor. Most articles were related to brain surgery. Of these studies, vascular surgery had the highest overall, with 13 of 40 articles, which include aneurysm clipping and other neurovascular surgeries. Twenty-two articles discussed cranial plus tumor surgeries, which included skull base, craniotomy, craniosynostosis, and transsphenoidal. Five studies were specific to spine surgery. Subjective outcome measures of neurosurgical residents were most commonly implemented, of which results were almost unanimously positive. CONCLUSIONS: 3D printing technology is rapidly expanding in health care and neurosurgery in particular. The technology is quickly improving, and several studies have shown the effectiveness of 3D printing for neurosurgical residency education and training.

Expression Levels of RAD51 Inversely Correlate with Survival of Glioblastoma Patients.

Treatment failures of glioblastoma (GBM) occur within high-dose radiation fields. We hypothesized that this is due to increased capacity for DNA damage repair in GBM. We identified 24 adult GBM patients treated with maximal safe resection followed by radiation with concurrent and adjuvant temozolomide. The mRNA from patients was quantified using NanoString Technologies' nCounter platform and compared with 12 non-neoplastic temporal lobe tissue samples as a control. Differential expression analysis identified seven DNA repair genes significantly upregulated in GBM tissues relative to controls (>4-fold difference, adjusted p values < 0.001). Among these seven genes, Cox proportional hazards models identified RAD51 to be associated with an increased risk of death (HR = 3.49; p = 0.03). Kaplan-Meier (KM) analysis showed that patients with high RAD51 expression had significantly shorter OS compared to low levels (median OS of 10.6 mo. vs 20.1 mo.; log-rank p = 0.03). Our findings were validated in a larger external dataset of 162 patients using publicly available gene expression data quantified by the same NanoString technology (median OS of 13.8 mo. vs. 17.4 mo; log-rank p = 0.006). Within this uniformly treated GBM population, RAD51, in the homologous recombination pathway, was overexpressed (vs. normal brain) and inversely correlated with OS. High RAD51 expression may be a prognostic biomarker and a therapeutic target in GBM.

Acoustoelectric imaging of deep dipoles in a human head phantom for guiding treatment of epilepsy.

OBJECTIVE: This study employs a human head model with real skull to demonstrate the feasibility of transcranial acoustoelectric brain imaging (tABI) as a new modality for electrical mapping of deep dipole sources during treatment of epilepsy with much better resolution and accuracy than conventional mapping methods. APPROACH: This technique exploits an interaction between a focused ultrasound (US) beam and tissue resistivity to localize current source densities as deep as 63 mm at high spatial resolution (1 to 4 mm) and resolve fast time-varying currents with sub-ms precision. MAIN RESULTS: Detection thresholds through a thick segment of the human skull at biologically safe US intensities was below 0.5 mA and within range of strong currents generated by the human brain. SIGNIFICANCE: This work suggests that 4D tABI may emerge as a revolutionary modality for real-time high-resolution mapping of neuronal currents for the purpose of monitoring, staging, and guiding treatment of epilepsy and other brain disorders characterized by abnormal rhythms.

Peripheral Nerve Stimulation for Refractory Trigeminal Pain: Recent Single-Institution Case Series With Long-Term Follow-Up and Review of the Literature.

BACKGROUND: Peripheral neurostimulation (PNS) for medically refractory trigeminal pain is an emerging alternative to traditional surgical approaches, with safety and efficacy demonstrated in several retrospective series and a prospective trial currently in progress. Many existing studies suffer from relatively small numbers and short or inconsistent follow-up, making balanced treatment assessment difficult. MATERIALS AND METHODS: Consecutive cases of trial and permanent placement of trigeminal branch stimulation electrodes by a single surgeon from May 2014 through January 2019 were retrospectively reviewed from a prospectively collected database, following the PROCESS guidelines for surgical case series. Outcomes were assessed at six months and at last follow-up. RESULTS: Ninteen patients underwent trial electrode placement, with 15 patients undergoing permanent system placement. The most common diagnoses were idiopathic trigeminal neuralgia Type 2 (N = 8) and trigeminal neuropathic pain (N = 7). Median follow-up was 14 months (range 6-58 months). At last follow-up, 12 of 15 implanted patients (80%) were still receiving stimulation, with mean (median) pain reduction of 52.3% (47.5%). Infection and revision rates were high, although erosion and migration, which have typically plagued trigeminal PNS surgery, did not occur. Implanted systems were well-tolerated, with excellent cosmetic outcomes and high patient satisfaction that proved durable over long follow-up. CONCLUSIONS: We present a single-institution series of PNS for complex craniofacial pain involving the trigeminal nerve. The procedure is safe, effective and durable over at least one year in the large majority of a well-selected patient population.