A systematic review on the efficacy of adjunctive surgical strategies during microvascular decompression for trigeminal neuralgia without intraoperative evidence of neurovascular conflict.

Aim of the present study was to conduct a comprehensive review of surgical strategies that can be offered to patients with trigeminal neuralgia undergoing microvascular decompression (MVD) surgery and without intraoperative evidence of neurovascular conflict, with a high pre-operative suspicion of conflict lacking intraoperative confirmation, or individuals experiencing recurrence after previous treatment. This systematic review followed established guidelines (PRISMA) to identify and critically appraise relevant studies. The review question was formulated according to the PICO (P: patients; I: intervention; C: comparison; O: outcomes) framework as follows. For patients with trigeminal neuralgia (P) undergoing MVD surgery (I) without demonstrable preoperative neurovascular conflict, high suspicion of conflict but no intraoperative confirmation or recurrence after previous treatment (C), do additional surgical techniques (nerve combing, neurapraxia, arachnoid lysis) (O) improve pain relief outcomes (O)? The search of the literature yielded a total of 221 results. Duplicate records were then removed (n = [76]). A total of 143 papers was screened, and 117 records were excluded via title and abstract screening; 26 studies were found to be relevant to our research question and were assessed for eligibility. Upon full-text review, 17 articles were included in the review, describing the following techniques; (1) internal neurolysis (n = 6) (2) arachnoid lysis/adhesiolysis (n = 2) (3) neurapraxia (n = 3) (4) partial rhizotomy of the sensory root (n = 4) (5) pontine descending tractotomy (n = 2). The risk of bias was assessed using the ROBINS-I (Risk of Bias in Non-randomized Studies - of Interventions) assessment tool. While the described techniques hold promise, further research is warranted to establish standardized protocols, refine surgical approaches, and comprehensively evaluate long-term outcomes.

Diffusion tensor imaging in detecting gliomas sub-regions of infiltration, local and remote recurrences: a systematic review.

Given that glioma cells tend to infiltrate and migrate along WM tracts, leading to demyelination and axonal injuries, Diffusion Tensor Imaging (DTI) emerged as a promising tool for identifying major "high-risk areas" of recurrence within the peritumoral brain zone (PBZ) or at a distance throughout the adjacents white matter tracts. Of our systematic review is to answer the following research question: In patients with brain tumor, is DTI able to recognizes within the peri-tumoral brain zone (PBZ) areas more prone to local (near the surgical cavity) or remote recurrence compared to the conventional imaging techniques?. We conducted a comprehensive literature search to identify relevant studies in line with the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) guidelines. 15 papers were deemed compatible with our research question and included. To enhance the paper's readability, we have categorized our findings into two distinct groups: the first delves into the role of DTI in detecting PBZ sub-regions of infiltration and local recurrences (n = 8), while the second group explores the feasibility of DTI in detecting white matter tract infiltration and remote recurrences (n = 7). DTI values and, within a broader framework, radiomics investigations can provide precise, voxel-by-voxel insights into the state of PBZ and recurrences. Better defining the regions at risk for potential recurrence within the PBZ and along WM bundles will allow targeted therapy.

Is There a Role for Machine Learning in Liquid Biopsy for Brain Tumors? A Systematic Review.

The paucity of studies available in the literature on brain tumors demonstrates that liquid biopsy (LB) is not currently applied for central nervous system (CNS) cancers. The purpose of this systematic review focused on the application of machine learning (ML) to LB for brain tumors to provide practical guidance for neurosurgeons to understand the state-of-the-art practices and open challenges. The herein presented study was conducted in accordance with the PRISMA-P (preferred reporting items for systematic review and meta-analysis protocols) guidelines. An online literature search was launched on PubMed/Medline, Scopus, and Web of Science databases using the following query: "((Liquid biopsy) AND (Glioblastoma OR Brain tumor) AND (Machine learning OR Artificial Intelligence))". The last database search was conducted in April 2023. Upon the full-text review, 14 articles were included in the study. These were then divided into two subgroups: those dealing with applications of machine learning to liquid biopsy in the field of brain tumors, which is the main aim of this review (n = 8); and those dealing with applications of machine learning to liquid biopsy in the diagnosis of other tumors (n = 6). Although studies on the application of ML to LB in the field of brain tumors are still in their infancy, the rapid development of new techniques, as evidenced by the increase in publications on the subject in the past two years, may in the future allow for rapid, accurate, and noninvasive analysis of tumor data. Thus making it possible to identify key features in the LB samples that are associated with the presence of a brain tumor. These features could then be used by doctors for disease monitoring and treatment planning.

Neuromodulation for Brain Tumors: Myth or Reality? A Narrative Review.

In recent years, research on brain cancers has turned towards the study of the interplay between the tumor and its host, the normal brain. Starting from the establishment of a parallelism between neurogenesis and gliomagenesis, the influence of neuronal activity on the development of brain tumors, particularly gliomas, has been partially unveiled. Notably, direct electrochemical synapses between neurons and glioma cells have been identified, paving the way for new approaches for the cure of brain cancers. Since this novel field of study has been defined "cancer neuroscience", anticancer therapeutic approaches exploiting these discoveries can be referred to as "cancer neuromodulation". In the present review, we provide an up-to-date description of the novel findings and of the therapeutic neuromodulation perspectives in cancer neuroscience. We focus both on more traditional oncologic approaches, aimed at modulating the major pathways involved in cancer neuroscience through drugs or genetic engineering techniques, and on electric stimulation proposals; the latter is at the cutting-edge of neuro-oncology.

Immunoregulatory effects of glioma-associated stem cells on the glioblastoma peritumoral microenvironment: a differential PD-L1 expression from core to periphery?

OBJECTIVE: Glioma-associated stem cells (GASCs) have been indicated as possible players in supporting growth and recurrence in glioblastoma. However, their role in modulating immune response in the peritumoral area has not yet been described. In this study, the authors aimed to investigate programmed death-ligand 1 (PD-L1) differential expression at the protein level in GASCs derived from different tumor areas (core, periphery, and surrounding healthy brain). METHODS: Tumor tissue samples were collected from patients who underwent surgery for a histopathologically confirmed diagnosis of glioblastoma. Sampling sites were confirmed via neuronavigation and categorized on 5-aminolevulinic acid (5-ALA) fluorescence as bright (ALA+), pale (ALA PALE), or negative (ALA-), which corresponds to the tumor mass, infiltrated peritumoral area, and healthy brain, respectively, during surgery. GASCs were first isolated from the 3 regions and analyzed; then Western blot analysis was used to evaluate the level of PD-L1 expression in the GASCs. RESULTS: Overall, 7 patients were included in the study. For all patients, the mean values ± SD of PD-L1 expression in GASCs for ALA+, ALA PALE, and ALA- were 1.12 ± 1.14, 0.89 ± 0.63, and 0.57 ± 0.18, respectively. The differentially expressed values of PD-L1 in GASCs sampled from the 3 areas were found to be significant (p < 0.05) for 3 of the 7 patients: patient S470 (ALA+ vs ALA- and ALA PALE vs ALA-), patient S473 (ALA+ vs ALA PALE and ALA PALE vs ALA-), and patient S509 (ALA+ vs ALA-). CONCLUSIONS: This analysis showed, for the first time, that GASCs expressed a constitutive level of PD-L1 and that PD-L1 expression in GASCs was not uniform among patients or within the same patient. GASC analysis combined with 5-ALA-guided sampling (from core to periphery) made it possible to highlight the role of the tumor microenvironment at the infiltrating margin, which might cause clinical resistance, opening interesting perspectives for the future.

The prevalence of imposter syndrome among young neurosurgeons and residents in neurosurgery: a multicentric study.

OBJECTIVE: Imposter syndrome (IS) occurs when high-achieving individuals have a pervasive sense of self-doubt combined with fear of being exposed as a fraud, despite objective measures of success. This is one of the main causes of burnout among professionals, threatening their mental health and general well-being. The prevalence and severity of IS among neurosurgery residents and young neurosurgeons has not been yet studied. The primary outcomes of this study were the prevalence and severity of IS. METHODS: An anonymous cross-sectional survey including both a demographic questionnaire (Clance Imposter Phenomenon Survey) and compensatory mechanisms was distributed to young neurosurgeons and residents in neurosurgery in Italy. RESULTS: A total of 103 responses were collected. The prevalence rate was 81.6%. Among the respondents with IS, 42.7% showed moderate signs, 27.2% frequent, and only 11.7% had an intense symptomatology. Level of education, female sex, and academic achievements were all identified as predictive factors of IS. CONCLUSIONS: A total of 81.6% of respondents reported potentially significant levels. The implications of IS on both the outcomes in patients and the well-being of neurosurgeons should be evaluated in future studies.

Are oral anticoagulants a risk factor for mild traumatic brain injury progression? A single-center experience focused on of direct oral anticoagulants and vitamin K antagonists.

BACKGROUND: Mild traumatic brain injury (TBI) in anticoagulated patients is a common challenge for emergency departments because of lack of appropriate epidemiological data and huge management variability for those under oral anticoagulation therapy. Given the discrepancies between guidelines, the aim of the present study was to quantify the association between oral anticoagulant therapy (either vitamin K antagonist (VKA) or direct oral anticoagulant (DOAC)) and the post-traumatic intracranial hemorrhage worsening compared to admission CT scan. METHODS: We included all consecutive records of patients admitted to our emergency department for mild TBI as chief complaint and with a positive admission CT scan. After statistical univariate comparison, cause-specific hazard ratio (HR) and 95% confidence interval (CI) were determined with the use of Cox proportional hazard model. RESULTS: In the study period, 4667 patients had a CT scan for mild TBI; 439 (9.4%) were found to have intracranial hemorrhage. Among these patients, 299 (68.1%) were prescribed observation and control CT: 46 (15.38%) were on anticoagulant therapy, 23 (50%) on VKA, and 23 (50%) on DOAC. In multivariate analysis, only oral anticoagulation therapy was significantly associated to an increased risk of intracranial hemorrhage progression (HR 2.58; 95% CI 1.411-4.703; p = .002 and HR 1.9; 95% CI 1.004-3.735; p = .0048 for VKA and DOAC, respectively). Surgery was due to isolated subdural hematoma in 87.5% of cases, to subdural hematoma associated with intraparenchymal hemorrhage in 9.38% and to intraparenchymal hemorrhage only in 3.12%; 13 cases (4.35%) deceased in intensive care unit. CONCLUSIONS: In our series, anticoagulation was associated to a significant increase in intracranial progression, leaving the question open as to what this implies in current clinical practice; subdural hematoma was the major finding associated to evolution and surgery. Against this background, further studies are needed to clarify patients' management and DOAC safety profile compared to VKA in mild TBI.

Predicting meningioma consistency and brain-meningioma interface with intraoperative strain ultrasound elastography: a novel application to guide surgical strategy.

OBJECTIVE: Providing new tools to improve surgical planning is considered a main goal in meningioma treatment. In this context, two factors are crucial in determining operating strategy: meningioma-brain interface and meningioma consistency. The use of intraoperative ultrasound (ioUS) elastosonography, a real-time imaging technique, has been introduced in general surgery to evaluate similar features in other pathological settings such as thyroid and prostate cancer. The aim of the present study was to evaluate ioUS elastosonography in the intraoperative prediction of key intracranial meningioma features and to evaluate its application in guiding surgical strategy. METHODS: An institutional series of 36 meningiomas studied with ioUS elastosonography is reported. Elastographic data, intraoperative surgical findings, and corresponding preoperative MRI features were classified, applying a score from 0 to 2 to both meningioma consistency and meningioma-brain interface. Statistical analysis was performed to determine the degree of agreement between meningioma elastosonographic features and surgical findings, and whether intraoperative elastosonography was a better predictor than preoperative MRI in assessing meningioma consistency and slip-brain interface, using intraoperative findings as the gold standard. RESULTS: A significantly high degree of reliability and agreement between ioUS elastographic scores and surgical finding scores was reported (intraclass correlation coefficient = 0.848, F = 12.147, p < 0.001). When analyzing both consistency and brain-tumor interface, ioUS elastography proved to have a rather elevated sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and positive (LR+) and negative likelihood ratio (LR-). This consideration was true especially for meningiomas with a hard consistency (sensitivity = 0.92, specificity = 0.96, PPV = 0.92, NPV = 0.96, LR+ = 22.00, LR- = 0.09) and for those presenting with an adherent slip-brain interface (sensitivity = 0.76, specificity = 0.95, PPV = 0.93, NPV = 0.82, LR+ = 14.3, LR- = 0.25). Furthermore, predictions derived from ioUS elastography were found to be more accurate than MRI-derived predictions, as demonstrated by McNemar's test results in both consistency (p < 0.001) and interface (p < 0.001). CONCLUSIONS: While external validation of the data is needed to transform ioUS elastography into a fully deployable clinical tool, this experience confirmed that it may be integrated into meningioma surgical planning, especially because of its rapidity and cost-effectiveness.

Do Minimally Invasive Approaches to Pediatric Orbital Tumors Provide an Advantage on Outcome and Efficiency?

OBJECTIVE: The present study evaluated whether minimally invasive approaches to orbital lesions could improve surgical, clinical, and aesthetic outcomes compared with more invasive ones. This is the first study specifically addressing this topic in children. METHODS: Children consecutively operated on from January 2010 to January 2020 were analyzed. Thirty patients matched the inclusion criteria and were divided into group A: 14 cases treated with traditional surgical approaches; and group B: 16 cases managed by minimally invasive approaches. RESULTS: There were no significant differences between the 2 groups in terms of demographic data and extent of tumor resection. Mean surgical time for the approach (40 minutes vs. 70 minutes, P < 0.0001), surgical complication such as periorbital edema (37% vs. 78%, P = 0.02) and dural tear (0 vs. 21%, P = 0.05), and procedures cost (P < 0.0001) were significantly reduced in group B. Regarding clinical outcomes, group B showed a significant reduction both in terms of postoperative pain (mean score based on visual pain scale was 2.9 vs. 4.1 P = 0.003) and mean hospitalization time (4.5 days vs. 5.5 days, P = 0.0004). The cosmetic outcome according to the Sloan classification was significantly better in group B as well (81% vs. 36% class I patients, P = 0.005). CONCLUSIONS: The use of mini-invasive approaches to orbital tumor has clear advantages in terms of surgical, clinical, and cosmetic outcomes in comparable patients; therefore, they should be preferred whenever feasible. Craniotomic approaches remain necessary for very large tumors.

Posterior Cranial Fossa Surgery with a 3 Dimensional Exoscope: A Single-Center Survey-Based Analysis and a Literature Review.

OBJECTIVE: The potential advantages of exoscopy have been discussed theoretically for a long time. Such a concept holds significance, especially in the specific setting of the posterior cranial fossa (PCF), characterized by complex anatomy and long and narrow surgical corridors with relatively extreme working angles. We aimed to: 1) analyze the institutional preliminary case-based data on the use of the Robotic 3D Exoscope AEOS Aesculap in three different PCF approaches: retrosigmoid (RSA), midline suboccipital (MSA), and supracerebellar infratentorial via feedbacks was collected using a 20-point questionnaire, and 2) perform a comprehensive review of the literature concerning the use of EX in PCF surgery. RESULTS: A total of 38 patients with neurosurgical pathologies underwent a neurosurgical procedure using the EX (Robotic 3D exoscope AEOS Aesculap) at our institution between January and March 2022. 21 surgeons were involved in the abovementioned PCF surgeries and answered the questionnaire. The main perceived advantages were in terms of ergonomics (67%), magnification (52%), and visualization of extreme angles. The main reported disadvantage was color vision (16, 76%), followed by manual mobility (24%). Concerning the review, the search of the literature yielded a total of 177 results. Upon full-text review, 17 articles were included, including 153 patients. CONCLUSIONS: In conclusion, our study provides a comprehensive evaluation of the advantages and challenges associated with using the exoscope in posterior fossa surgery, setting a precedent as the first to report on a questionnaire-based analysis of exoscope utilization in this specific domain.

H3K27-Altered Diffuse Glioma of the Spinal Cord in Adult Patients: A Qualitative Systematic Review and Peculiarity of Radiological Findings.

Background: Primary spinal cord diffuse gliomas (SpDG) are rare tumors that may harbor, like diffuse intrinsic pontine gliomas (DIPG), H3K27M mutations. According to the WHO (2021), SpDGs are included in diffuse midline H3K27-altered gliomas, which occur more frequently in adults and show unusual clinical presentation, neuroradiological features, and clinical behavior, which differ from H3 G34-mutant diffuse hemispheric glioma. Currently, homogeneous adult-only case series of SpDG, with complete data and adequate follow-up, are still lacking. Methods: We conducted a qualitative systematic review, focusing exclusively on adult and young adult patients, encompassing all studies reporting cases of primitive, non-metastatic SpDG with H3K27 mutation. We analyzed the type of treatment administered, survival, follow-up duration, and outcomes. Results: We identified 30 eligible articles published between 1990 and 2023, which collectively reported on 62 adult and young adult patients with primitive SpDG. Postoperative outcomes were assessed based on the duration of follow-up, with outcomes categorized as either survival or mortality. Patients who underwent surgery were followed up for a mean duration of 17.37 months, while those who underwent biopsy had a mean follow-up period of 14.65 months. Among patients who were still alive, the mean follow-up duration was 18.77 months. The radiological presentation of SpDG varies widely, indicating its lack of uniformity. Conclusion: Therefore, we presented a descriptive scenario where SpDG was initially suspected to be a meningioma, but was later revealed to be a malignant SpDG with H3K27M mutation.

Navigating Complexity: A Comprehensive Approach to Middle Cerebral Artery Aneurysms.

Background: The concept of aneurysm "complexity" has undergone significant changes in recent years, with advancements in endovascular treatments. However, surgical clipping remains a relevant option for middle cerebral artery (MCA) aneurysms. Hence, the classical criteria used to define surgically complex MCA aneurysms require updating. Our objective is to review our institutional series, considering the impacts of various complexity features, and provide a treatment strategy algorithm. Methods: We conducted a retrospective review of our institutional experience with "complex MCA" aneurysms and analyzed single aneurysmal-related factors influencing treatment decisions. Results: We identified 14 complex cases, each exhibiting at least two complexity criteria, including fusiform shape (57%), large size (35%), giant size (21%), vessel branching from the sac (50%), intrasaccular thrombi (35%), and previous clipping/coiling (14%). In 92% of cases, the aneurysm had a wide neck, and 28% exhibited tortuosity or stenosis of proximal vessels. Conclusions: The optimal management of complex MCA aneurysms depends on a decision-making algorithm that considers various complexity criteria. In a modern medical setting, this process helps clarify the choice of treatment strategy, which should be tailored to factors such as aneurysm morphology and patient characteristics, including a combination of endovascular and surgical techniques.

Stereoscopic Monitoring Technique for Motor Area Tumors.

BACKGROUND: The balance between comprehensive intraoperative neurophysiological monitoring (IONM) for both upper and lower limbs while ensuring the reliability of motor evoked potentials (MEPs) is paramount in motor area surgery. It is commonly difficult to obtain good simultaneous stimulation of both upper and lower limbs. A series of factors can bias MEP accuracy, and inappropriate stimulation intensity can result in unreliable monitoring. The presented IONM technique is based on the concurrent use of both transcranial and cortical strip electrodes to facilitate simultaneous monitoring of both upper and lower limbs at optimized stimulation intensities to increase IONM accuracy during motor area surgery. METHODS: Ten nonconsecutive motor area tumors were studied. Good visualization of both limbs was observed in the series at a low amperage (1.2 mA from the strip electrode and 165.3 mA from the transcranial electrode). RESULTS: Our analysis confirms concordance between the IONM data and postoperative outcomes. An MEP reduction >20% and >50% correlated with postoperative modified Rankin scale score changes without false-negative IONM findings. CONCLUSIONS: The technique was demonstrated to be accurate in providing a good simultaneous neurophysiological evaluation of both upper and lower limbs with an optimized and stimulation amplitude. The technique results in a low encumbrance of electrodes in the surgical field. Our results have confirmed the "proof of concept," its reliability and feasibility.

"FALSE FRIENDS" IN LANGUAGE SUBCORTICAL MAPPING: A SYSTEMATIC LITERATURE REVIEW.

BACKGROUND: Subcortical brain mapping in awake glioma surgery might optimize the extent of resection while minimizing neurological morbidity, but it requires a correct interpretation of responses evoked during surgery. AIMS: To define, with a systematic review: 1. a comprehensive 'map' of the principal white matter (WM) bundles involved in awake surgery on language-related networks, describing the most employed tests and the expected responses; 2. In linguistics, a false friend is a word in a different language that looks or sounds like a word in given language but differs significantly in meaning. Similarly, our aim is to give the surgeons a comprehensive review of potentially misleading responses, namely "false friends", in subcortical language mapping. METHODS: PRISMA guidelines were followed. Standardized data extraction was conducted. RESULTS: Out of a total of 224 initial papers, 67 were included for analysis. Expected responses, common tests, and potential "false friends" were recorded for each of the following WM bundles: Frontal Aslant Tract, Superior and Inferior Longitudinal fascicles, Arcuate Fascicle, Inferior Fronto-Occipital Fascicle, Uncinate Fascicle. Practical examples are discussed to underline the risk of intraoperative fallouts ("false friends") that might lead to an early interruption (false positive) or a risky surgical removal (false negative). CONCLUSION: This paper represents a critical review of the present status of subcortical awake mapping and underlines practical "false-friend" in mapping critical crossroads in language-related networks.

The prevalence of imposter syndrome among neurosurgeons in Europe: An EANS YNC survey.

Introduction: Imposter syndrome (IS), characterized by persistent doubts about one's abilities and fear of exposure as a fraud, is a prevalent psychological condition, particularly impacting physicians. In neurosurgery, known for its competitiveness and demands, the prevalence of IS remains high. Research question: Recognizing the limited literature on IS within the neurosurgical community, this European survey aimed to determine its prevalence among young neurosurgeons and identify associated factors. Material and methods: The survey, conducted by the Young Neurosurgeon Committee of the European Association of Neurosurgical Societies, gathered responses from 232 participants. The survey included demographics, the Clance Imposter Phenomenon Survey (CIPS), and an analysis of potential compensatory mechanisms. Results: Nearly 94% of respondents exhibited signs of IS, with the majority experiencing moderate (36.21%) or frequent (40.52%) symptoms. Analyses revealed associations between IS and factors such as level of experience, sex, and board-certification. Discussion and conclusion: The findings suggest a significant prevalence of IS among young neurosurgeons, with notable associations with sex and level of experience. Compensatory mechanisms, such as working hours, article reading, and participation in events, did not show significant correlations with IS. Notably, male sex emerged as an independent protective factor against frequent/intense IS, while reading more than five articles per week was identified as a risk factor. The identification of protective and risk factors, particularly the influence of gender and reading habits, contributes valuable insights for developing targeted interventions to mitigate IS and improve the well-being of neurosurgeons.

Predicting Role of GFAP and UCH-L1 biomarkers in Spontaneous Subarachnoid Hemorrhage: a preliminary study to evaluate in the short-term their correlation with severity of bleeding and prognosis.

BACKGROUND: Spontaneous non-traumatic subarachnoid hemorrhage (sSAH) is a severe brain vascular accident. Glial fibrillary acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) can be theoretically assayed to predict a patient's progression, picturing different aspects of clinical failure after sSAH. The study aims to: a) explore the correlation between sSAH blood volume and biomarkers variation; b) evaluate if these can be predictive of the neurogenic response after sSAH and be prognostic of patient outcome; c) establish eventual threshold levels of biomarkers to define patients' clinical outcome. METHODS: Blood volumetry at CT scan upon admission, GFAP and UCH-L1 were collected at 24 h, at 72 h, and after 7 days from hemorrhage. Trends and cut-off serum sampling were determined. Clinical outcome was assessed with mRS scale at 14 days. RESULTS: A strong correlation between GFAP and UCH-L1 and blood diffusion volume in all explored serum intervals related to unfavorable outcome. GFAP and UCH-L1 were very early predictors of unfavorable outcomes at 24 h from sSAH (p = 0.002 and 0.011 respectively). Threshold levels of UCH-L1 apparently revealed a very early, early and late predictor of unfavorable outcomes. CONCLUSION: GFAP and UCH-L1 represent a potential tool for prompt monitoring and customization of therapies in neurosurgical patients.

Reducing the Gap in Neurosurgical Education in LMICs: A Report of a Non-Profit Educational Program.

INTRODUCTION: Central to neurosurgical care, neurosurgical education is particularly needed in low- and middle-income countries (LMICs), where opportunities for neurosurgical training are limited due to social and economic constraints and an inadequate workforce. The present paper aims (1) to evaluate the validity and usability of a cadaver-free hybrid system in the context of LMICs and (2) to report their learning needs and whether the courses meet those needs via a comprehensive survey. METHODS: From April to November 2021, a non-profit initiative consisting of a series of innovative cadaver-free courses based on virtual and practical training was organized. This project emerged from a collaboration between the Young Neurosurgeons Forum of the World Federation of Neurological Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and UpSurgeOn, an Italian hi-tech company specialized in simulation technologies, creator of the UpSurgeOn Box, a hyper-realistic simulator of cranial approaches fused with augmented reality. Over that period, 11 cadaver-free courses were held in LMICs using remote hands-on Box simulators. RESULTS: One hundred sixty-eight participants completed an online survey after course completion of the course. The anatomical accuracy of simulators was overall rated high by the participant. The simulator provided a challenging but manageable learning curve, and 86% of participants found the Box to be very intuitive to use. When asked if the sequence of mental training (app), hybrid training (Augmented Reality), and manual training (the Box) was an effective method of training to fill the gap between theoretical knowledge and practice on a real patient/cadaver, 83% of participants agreed. Overall, the hands-on activities on the simulators have been satisfactory, as well as the integration between physical and digital simulation. CONCLUSIONS: This project demonstrated that a cadaver-free hybrid (virtual/hands-on) training system could potentially participate in accelerating the learning curve of neurosurgical residents, especially in the setting of limited training possibilities such as LMICs, which were only worsened during the COVID-19 pandemic.

Technical Pearls to Effectively Use 5-ALA in Fluorescence-Guided Tumor Resection-5 Lessons from the Operating Room.

BACKGROUND: Since its introduction in 2007 in Europe and in 2017 in the United States, 5-ALA has demonstrated an undisputed advantage in providing real-time tumor visualization. The aim of the present paper is to summarize our institutional experience over a decade of routine 5-ALA-guided procedures in order to provide five surgical tricks to ease surgical workflow. METHODS: Data were collected from 822 patients diagnosed with histopathologically confirmed high-grade gliomas (HGG)-according to the WHO 2021 criteria-who underwent surgery at the Fondazione Policlinico Universitario Agostino Gemelli between January 2012 and January 2022. RESULTS: From our large institutional experience, the learned technical pearls were grouped in five distinct domains: 1. Analysis of visualization, overall workflow, and technical recommendations to improve intraoperative set-up; 2. Techniques to reduce the risk of inadvertent residuals and failure to evocate fluorescence; 3. Analysis of specific surgical conditions favoring remnants; 4. Assessment of different degrees of fluorescence and their surgical meaning; 5. Analysis of false positive cases. CONCLUSIONS: With all the limitations of a qualitative and retrospective analysis, this paper was specifically conceived as a vademecum for educational purposes to promote and maximize 5-ALA employment.

Applicability and efficacy of ultrasound elastography in neurosurgery: a systematic review of the literature.

INTRODUCTION: Neurosurgery is one of the fields in which intraoperative imaging is paramount. One of these main imaging tools that have been acquiring the interest of the neurosurgical community is Ultrasound elastography (USE), which is an imaging technology sensitive to tissue stiffness. Here we present a systematic review of the use of USE in neurosurgery. EVIDENCE ACQUISITION: A systematic review of the literature has been performed, according to the PRISMA guideline, for the last 30 years on 3 different databases (MEDLINE, Scopus, and Cochrane), to gather all the studies on the use of ultrasound elastography for neurosurgical pathologies, including both clinical and laboratory studies. EVIDENCE SYNTHESIS: A total of 15 articles met the inclusion criteria. USE has widely and safely been used especially for oncological lesions (meningiomas and gliomas) and focal cortical dysplasia. However, there are also encouraging laboratory studies about its application for the management of traumatic brain injury, and ischemic stroke. CONCLUSIONS: This systematic review showed that, despite the lack of strong evidence, USE is a valid intraoperative tool, especially in oncological neurosurgery.