Complex intracranial aneurysms: a DELPHI study to define associated characteristics.

PURPOSE: Intracranial aneurysms present significant health risks, as their rupture leads to subarachnoid haemorrhage, which in turn has high morbidity and mortality rates. There are several elements affecting the complexity of an intracranial aneurysm. However, criteria for defining a complex intracranial aneurysm (CIA) in open surgery and endovascular treatment could differ, and actually there is no consensus on the definition of a "complex" aneurysm. This DELPHI study aims to assess consensus on variables defining a CIA. METHODS: An international panel of 50 members, representing various specialties, was recruited to define CIAs through a three-round Delphi process. The panelists participated in surveys with Likert scale responses and open-ended questions. Consensus criteria were established to determine CIA variables, and statistical analysis evaluated consensus and stability. RESULTS: In open surgery, CIAs were defined by fusiform or blister-like shape, dissecting aetiology, giant size (≥ 25 mm), broad neck encasing parent arteries, extensive neck surface, wall calcification, intraluminal thrombus, collateral branch from the sac, location (AICA, SCA, basilar), vasospasm context, and planned bypass (EC-IC or IC-IC). For endovascular treatment, CIAs included giant size, very wide neck (dome/neck ratio ≤ 1:1), and collateral branch from the sac. CONCLUSIONS: The definition of aneurysm complexity varies by treatment modality. Since elements related to complexity differ between open surgery and endovascular treatment, these consensus criteria of CIAs could even guide in selecting the best treatment approach.

Simulation to become a better neurosurgeon. An international prospective controlled trial: The Passion study.

Introduction: Surgical training traditionally adheres to the apprenticeship paradigm, potentially exposing trainees to an increased risk of complications stemming from their limited experience. To mitigate this risk, augmented and virtual reality have been considered, though their effectiveness is difficult to assess. Research question: The PASSION study seeks to investigate the improvement of manual dexterity following intensive training with neurosurgical simulators and to discern how surgeons' psychometric characteristics may influence their learning process and surgical performance. Material and methods: Seventy-two residents were randomized into the simulation group (SG) and control group (CG). The course spanned five days, commencing with assessment of technical skills in basic procedures within a wet-lab setting on day 1. Over the subsequent core days, the SG engaged in simulated procedures, while the CG carried out routine activities in an OR. On day 5, all residents' technical competencies were evaluated. Psychometric measures of all participants were subjected to analysis. Results: The SG demonstrated superior performance (p < 0.0001) in the brain tumour removal compared to the CG. Positive learning curves were evident in the SG across the three days of simulator-based training for all tumour removal tasks (all p-values <0.05). No significant differences were noted in other tasks, and no meaningful correlations were observed between performance and any psychometric parameters. Discussion and conclusion: A brief and intensive training regimen utilizing 3D virtual reality simulators enhances residents' microsurgical proficiency in brain tumour removal models. Simulators emerge as a viable tool to expedite the learning curve of in-training neurosurgeons.

The outcomes measured and reported in observational studies of incidental and untreated intracranial meningioma: A systematic review.

Background: The clinical management of patients with incidental intracranial meningioma varies markedly and is often based on clinician choice and observational data. Heterogeneous outcome measurement has likely hampered knowledge progress by preventing comparative analysis of similar cohorts of patients. This systematic review aimed to summarize the outcomes measured and reported in observational studies. Methods: A systematic literature search was performed to identify published full texts describing active monitoring of adult cohorts with incidental and untreated intracranial meningioma (PubMed, EMBASE, MEDLINE, and CINAHL via EBSCO, completed January 24, 2022). Reported outcomes were extracted verbatim, along with an associated definition and method of measurement if provided. Verbatim outcomes were de-duplicated and the resulting unique outcomes were grouped under standardized outcome terms. These were classified using the taxonomy proposed by the "Core Outcome Measures in Effectiveness Trials" (COMET) initiative. Results: Thirty-three published articles and 1 ongoing study were included describing 32 unique studies: study designs were retrospective n = 27 and prospective n = 5. In total, 268 verbatim outcomes were reported, of which 77 were defined. Following de-duplication, 178 unique verbatim outcomes remained and were grouped into 53 standardized outcome terms. These were classified using the COMET taxonomy into 9 outcome domains and 3 core areas. Conclusions: Outcome measurement across observational studies of incidental and untreated intracranial meningioma is heterogeneous. The standardized outcome terms identified will be prioritized through an eDelphi survey and consensus meeting of key stakeholders (including patients), in order to develop a Core Outcome Set for use in future observational studies.

The outcomes measured and reported in intracranial meningioma clinical trials: A systematic review.

Background: Meningioma clinical trials have assessed interventions including surgery, radiotherapy, and pharmacotherapy. However, agreement does not exist on what, how, and when outcomes of interest should be measured. To do so would allow comparative analysis of similar trials. This systematic review aimed to summarize the outcomes measured and reported in meningioma clinical trials. Methods: Systematic literature and trial registry searches were performed to identify published and ongoing intracranial meningioma clinical trials (PubMed, Embase, Medline, CINAHL via EBSCO, and Web of Science, completed January 22, 2022). Reported outcomes were extracted verbatim, along with an associated definition and method of measurement if provided. Verbatim outcomes were deduplicated and the resulting unique outcomes were grouped under standardized outcome terms. These were classified using the taxonomy proposed by the "Core Outcome Measures in Effectiveness Trials" (COMET) initiative. Results: Thirty published articles and 18 ongoing studies were included, describing 47 unique clinical trials: Phase 2 n = 33, phase 3 n = 14. Common interventions included: Surgery n = 13, radiotherapy n = 8, and pharmacotherapy n = 20. In total, 659 verbatim outcomes were reported, of which 84 were defined. Following de-duplication, 415 unique verbatim outcomes remained and were grouped into 115 standardized outcome terms. These were classified using the COMET taxonomy into 29 outcome domains and 5 core areas. Conclusions: Outcome measurement across meningioma clinical trials is heterogeneous. The standardized outcome terms identified will be prioritized through an eDelphi survey and consensus meeting of key stakeholders (including patients), in order to develop a core outcome set for use in future meningioma clinical trials.

Endovascular neurosurgery in Europe: an International Survey and future perspectives.

BACKGROUND: Recent advancements in neurosurgery have transformed patient care through minimally invasive procedures and led to a notable surge in endovascular treatments. However, the regulatory landscape governing these procedures across European countries varies, impacting treatment access and collaboration. This paper discusses the results of a survey on European legislation regarding endovascular neurosurgery, exploring current practices and speculating on the field's future. METHODS: An e-mail survey was distributed to 41 European countries, targeting European member societies within the EANS. Thirty-seven completed questionnaires were returned, providing insights into neuroendovascular treatment legislation and restrictions. RESULTS: Legislation and certification varied across the surveyed countries, with only two countries prohibiting endovascular neurosurgery. Eight countries required specific fellowship programs. Resistance from radiologists was noted in many countries. CONCLUSIONS: Despite growing support for neurosurgeons performing endovascular treatments in Europe, challenges persist. Specialized care, improved access, and a broadening spectrum of treatable conditions contribute to the argument for involvement of neurosurgeons.

Altered hierarchical auditory predictive processing after lesions to the orbitofrontal cortex.

Orbitofrontal cortex (OFC) is classically linked to inhibitory control, emotion regulation, and reward processing. Recent perspectives propose that the OFC also generates predictions about perceptual events, actions, and their outcomes. We tested the role of the OFC in detecting violations of prediction at two levels of abstraction (i.e., hierarchical predictive processing) by studying the event-related potentials (ERPs) of patients with focal OFC lesions (n = 12) and healthy controls (n = 14) while they detected deviant sequences of tones in a local-global paradigm. The structural regularities of the tones were controlled at two hierarchical levels by rules defined at a local (i.e., between tones within sequences) and at a global (i.e., between sequences) level. In OFC patients, ERPs elicited by standard tones were unaffected at both local and global levels compared to controls. However, patients showed an attenuated mismatch negativity (MMN) and P3a to local prediction violation, as well as a diminished MMN followed by a delayed P3a to the combined local and global level prediction violation. The subsequent P3b component to conditions involving violations of prediction at the level of global rules was preserved in the OFC group. Comparable effects were absent in patients with lesions restricted to the lateral PFC, which lends a degree of anatomical specificity to the altered predictive processing resulting from OFC lesion. Overall, the altered magnitudes and time courses of MMN/P3a responses after lesions to the OFC indicate that the neural correlates of detection of auditory regularity violation are impacted at two hierarchical levels of rule abstraction.

An objective skill assessment framework for microsurgical anastomosis based on ALI scores.

INTRODUCTION: The current assessment and standardization of microsurgical skills are subjective, posing challenges in reliable skill evaluation. We aim to address these limitations by developing a quantitative and objective framework for accurately assessing and enhancing microsurgical anastomosis skills among surgical trainees. We hypothesize that this framework can differentiate the proficiency levels of microsurgeons, aligning with subjective assessments based on the ALI score. METHODS: We select relevant performance metrics from the literature on laparoscopic skill assessment and human motor control studies, focusing on time, instrument kinematics, and tactile information. This information is measured and estimated by a set of sensors, including cameras, a motion capture system, and tactile sensors. The recorded data is analyzed offline using our proposed evaluation framework. Our study involves 12 participants of different ages ([Formula: see text] years) and genders (nine males and three females), including six novice and six intermediate subjects, who perform surgical anastomosis procedures on a chicken leg model. RESULTS: We show that the proposed set of objective and quantitative metrics to assess skill proficiency aligns with subjective evaluations, particularly the ALI score method, and can effectively differentiate novices from more proficient microsurgeons. Furthermore, we find statistically significant disparities, where microsurgeons with intermediate level of skill proficiency surpassed novices in both task speed, reduced idle time, and smoother, briefer hand displacements. CONCLUSION: The framework enables accurate skill assessment and provides objective feedback for improving microsurgical anastomosis skills among surgical trainees. By overcoming the subjectivity and limitations of current assessment methods, our approach contributes to the advancement of surgical education and the development of aspiring microsurgeons. Furthermore, our framework emerges to precisely distinguish and classify proficiency levels (novice and intermediate) exhibited by microsurgeons.

The Integration of 3D Virtual Reality and 3D Printing Technology as Innovative Approaches to Preoperative Planning in Neuro-Oncology.

Our study explores the integration of three-dimensional (3D) virtual reality (VR) and 3D printing in neurosurgical preoperative planning. Traditionally, surgeons relied on two-dimensional (2D) imaging for complex neuroanatomy analyses, requiring significant mental visualization. Fortunately, nowadays advanced technology enables the creation of detailed 3D models from patient scans, utilizing different software. Afterwards, these models can be experienced through VR systems, offering comprehensive preoperative rehearsal opportunities. Additionally, 3D models can be 3D printed for hands-on training, therefore enhancing surgical preparedness. This technological integration transforms the paradigm of neurosurgical planning, ensuring safer procedures.

Trans-lateral ventricular approach for surgical treatment of high-located P2-P3 junction posterior cerebral artery aneurysms: from anatomical research to clinical application.

BACKGROUND: Posterior cerebral artery (PCA) aneurysms, though rare, pose treatment challenges. Endovascular therapy is the preferred option, but microsurgery becomes necessary in certain cases. Various microsurgical approaches have been suggested for PCA aneurysms, particularly those at the P2-P3 junction. This study highlights the trans-lateral ventricular approach (TVA) for addressing these complex aneurysms. This study aims to assess the feasibility and safety of the trans-lateral ventricular approach (TVA) for treating high-located complex PCA aneurysms at the P2-P3 junction. The study evaluates both clinical outcomes and anatomical considerations. METHODS: Two cases of PCA aneurysms at the P2-P3 junction were treated using TVA in 2019. Navigation-guided entry via the interparietal sulcus was planned. Ventriculostomy was performed from the cortex to the lateral ventricle's atrium. Medial atrial floor dissection exposed PCA's P2-P3 segments. Neuronavigation and ultrasound-aided guidance was used. Anatomical studies on fixed and contrast-perfused specimens refined the approach. RESULTS: Both cases saw successful aneurysm clipping. The unruptured aneurysm patient was discharged in 6 days. The poor-grade SAH patient required extended ICU care, moving to rehabilitation with mRS = 4. The unruptured complex aneurysm case exhibited no deficits, returning to work in 3 months. Anatomical dissections validated TVA for high-located P2-P3 junction PCA aneurysms. CONCLUSION: While endovascular therapy remains primary, this study demonstrates the viability of navigation-guided TVA for select high-located P2-P3 junction PCA aneurysms. Successes and challenges underscore the importance of patient selection and anatomical awareness.

Tools and Modalities for Postural Ergonomics Research in Surgery and Neurosurgery.

Work-related musculoskeletal disorders (WMSDs) are common amongst neurosurgeons and can affect a surgeon's ability to operate. Performing surgical ergonomics research is important to minimize the prevalence and effect of WMSDs on the surgeons. The aim of this review is to highlight some of the most important objective and subjective tools available for surgical ergonomics research. Subjective tools can be divided into three categories: (1) questionnaires (either validated or non-validated) filled out by the participants, (2) survey assessments/standardized scoring systems filled out by the researchers, and (3) video analysis. Subjective tools have the drawbacks of recall bias and intra-rater and inter-rater variability. Some of the most important objective tools available are surface electromyography, force plate/pressure sensors analysis, inertial measurement units (IMUs) and kinematics data capturing using reflective markers. Although these modalities do not have the drawbacks that hinder the use of subjective tools, using most of them in the real-life operating theatre, with the exception of IMUs, is challenging. Conducting surgical ergonomics research is important to optimize the performance of neurosurgeons. The advancements towards wearable, wireless technologies will make it easier for surgeons to perform ergonomics research in the operating room.

Cavernous malformations of the central nervous system: An international consensus statement.

Introduction: Cavernous malformations (CM) of the central nervous system constitute rare vascular lesions. They are usually asymptomatic, which has allowed their management to become quite debatable. Even when they become symptomatic their optimal mode and timing of treatment remains controversial. Research question: A consensus may navigate neurosurgeons through the decision-making process of selecting the optimal treatment for asymptomatic and symptomatic CMs. Material and methods: A 17-item questionnaire was developed to address controversial issues in relation to aspects of the treatment, surgical planning, optimal surgical strategy for specific age groups, the role of stereotactic radiosurgery, as well as a follow-up pattern. Consequently, a three-stage Delphi process was ran through 19 invited experts with the goal of reaching a consensus. The agreement rate for reaching a consensus was set at 70%. Results: A consensus for surgical intervention was reached on the importance of the patient's age, symptomatology, and hemorrhagic recurrence; and the CM's location and size. The employment of advanced MRI techniques is considered of value for surgical planning. Observation for asymptomatic eloquent or deep-seated CMs represents the commonest practice among our panel. Surgical resection is considered when a deep-seated CM becomes symptomatic or after a second bleeding episode. Asymptomatic, image-proven hemorrhages constituted no indication for surgical resection for our panelists. Consensus was also reached on not resecting any developmental venous anomalies, and on resecting the associated hemosiderin rim only in epilepsy cases. Discussion and conclusion: Our Delphi consensus provides an expert common practice for specific controversial issues of CM patient management.

Endoscopic endonasal pituitary surgery: How we do it. Consensus statement on behalf of the EANS skull base section.

Introduction and research question: The use of an endoscope in skull base surgery provides a panoramic close-up view over the intracranial structures from multiple angles with excellent illumination, thus permitting greater extent of resection of tumors arising at sellar area, mostly represented by PitNet - Pituitary neuroendocrine tumors, with higher likelihood of preserving vital/intact gland tissue. For this refined specialty of neurosurgery, unique skills need to be acquired along a steep learning curve. Material and methods: EANS (European Association of Neurosurgical Societies) skull base section panelists were enrolled and 11 completed the survey: the goal was to provide a consensus statement of the endoscopic endonasal approach for pituitary adenoma surgery. Results: The survey consisted of 44 questions covering demographics data (i.e., academic/non-academic center, case load, years of experience), surgical techniques (i.e., use of neuronavigation, preoperative imaging), and follow-up management. Discussion and conclusions: In this paper we identified a series of tips and tricks at different phases of an endoscopic endonasal pituitary surgery procedure to underline the crucial steps to perform successful surgery and reduce complications: we took in consideration the principles of the surgical technique, the knowledge of the anatomy and its variations, and finally the importance of adjoining specialties experts.