Odontoid Fractures: A Review of the Current State of the Art.

Odontoid fractures (OFs) represent up to 15% of all cervical fractures encountered and present most commonly amongst elderly patients, typically in the setting of low energy trauma such as falls. The Anderson and D'Alonzo classification and Roy-Camille subtype description are the most clinically noteworthy descriptions of OFs used. Even though most patients will not present with neurological injury, mechanical instability can occur with type II and type III (Anderson and D'Alonzo) fractures, particularly if the transverse ligament of the atlas is ruptured; however, this is very rare. Conservative treatment is usually employed for type I and type III injuries, and to a varying degree for non-displaced type II injuries. Surgical treatment is typically reserved for type II fractures, patients with neurological injury, and in the setting of other associated fractures or ligamentous injury. Anterior screw fixation is a viable option in the setting of a favorable fracture line orientation in type II fractures, whereas posterior C1-C2 screw fixation is an option for any type II or type III fracture presentation. There is evidence that surgery for type II fractures has higher rates of union and lower mortality than nonoperative treatments. While surgical options have increased over the decades and the management of OF has been optimized by considering fracture subtypes and patient factors, there remains a significant morbidity and mortality associated with OFs. The aging population and changing demographics suggest that there will be an ongoing rise in the incidence of OFs. Therefore, the appropriate management of these cases will be essential for ensuring optimization of health care resources and the quality of life of affected patients.

Brain Metastases from Genito-Urinary Cancers in the Canton of Geneva (Switzerland): Study of Incidence, Management and Outcomes.

BACKGROUND: Incidence of brain metastases is precisely unknown and there is no clear consensus on their management. We aimed to determine the incidence of brain metastases among patients with genito-urinary primaries, present patients' characteristics and identify prognostic factors. METHOD: We identified 51 patients treated in Geneva University Hospitals between January 1992 and December 2019. We retrospectively correlated their overall survival with 23 variables. We repeated a multivariate analysis with significant variables. RESULTS: Overall incidence of Brain Metastases (BMs) among Genito-Urinary (GU) patients is estimated to be 1.76% (range per primary GU tumour type: 0.00-6.65%). BMs originate from germ cell tumours in two cases (3.92%), from urothelial cell carcinoma in 15 cases (29.41%), from prostate cancer in 13 cases (25.49%), and from renal cell carcinoma in 21 cases (41.18%); there are no BMs from penile cancer in our cohort. The median age at BM diagnosis is 67 years old (range: 25-92). Most patients (54%) have a stage IV disease at initial diagnosis and 11 patients (22%) have BM at initial diagnosis. Only six patients (12%) are asymptomatic at BM diagnosis. The median Overall Survival (OS) from BM diagnosis is 3 months (range: 0-127). Five patients (10%) are long survivors (OS > 24 months). OS is significantly influenced by patient performance status and administration of systemic treatment. In the absence of meningeal carcinomatosis, OS is influenced by systemic treatment and stereotactic radiosurgery. We also apply the Graded Prognostic Assessment (GPA) score to our cohort and note significant differences between groups. CONCLUSION: Brain metastases from solid tumours is not a uniform disease, with a prognosis varying a lot among patients. The optimal management for patients with genito-urinary malignancies with brain metastases remain unclear and further research is needed.

Changes in cortical thickness: yet another indication of supraspinal adaptations in degenerative cervical myelopathy.

This scientific commentary refers to 'Patterns of cortical thickness alterations in degenerative cervical myelopathy: associations with dexterity and gait dysfunctions', by Muhammad et al. (https://doi.org/10.1093/braincomms/fcae279).

Self-other voice discrimination task: A potential neuropsychological tool for clinical assessment of self-related deficits.

Background: Deficits in self are commonly described through different neuro-pathologies, based on clinical evaluations and experimental paradigms. However, currently available approaches lack appropriate clinical validation, making objective evaluation and discrimination of self-related deficits challenging. Methods: We applied a statistical standardized method to assess the clinical discriminatory capacity of a Self-Other Voice Discrimination (SOVD) task. This task, validated experimentally as a marker for self-related deficits, was administered to 17 patients eligible for neurosurgery due to focal hemispheric brain tumors or epileptic lesions. Results: The clinical discriminatory capacity of the SOVD task was evident in three patients who exhibited impairments for self-voice perception that could not be predicted by other neuropsychological deficits. Impairments in other-voice perception were linked to inhibitory neuropsychological deficits, suggesting a potential association with executive deficits in voice recognition. Conclusions: This exploratory study highlights the clinical discriminatory potential of the SOVD task and suggests that it could complement the standard neuropsychological assessment, paving the way for enhanced diagnoses and tailored treatments for self-related deficits.

PTPRZ1-targeting RNA CAR T cells exert antigen-specific and bystander antitumor activity in glioblastoma.

The great success of chimeric antigen receptor (CAR) T-cell therapy in the treatment of patients with B-cell malignancies has prompted its translation to solid tumors. In the case of glioblastoma (GBM), clinical trials have shown modest efficacy, but efforts to develop more effective anti-GBM CAR T cells are ongoing. In this study, we selected PTPRZ1 as a target for GBM treatment. We isolated six anti-human PTPRZ1 scFv from a human phage display library and produced 2nd generation CAR T cells in an RNA format. Patient-derived GBM PTPRZ1-knock-in cell lines were used to select the CAR construct that showed high cytotoxicity while consistently displaying high CAR expression (471_28z). CAR T cells incorporating 471_28z were able to release IFN-γ, IL-2, TNF-α, Granzyme B, IL-17A, IL-6, and soluble FasL, and displayed low tonic signaling. Additionally, they maintained an effector memory phenotype after in vitro killing. In addition, 471_28z CAR T cells displayed strong bystander killing against PTPRZ1-negative cell lines after pre-activation by PTPRZ1-positive tumor cells but did not kill antigen-negative non-tumor cells. In an orthotopic xenograft tumor model using NSG mice, a single dose of anti-PTPRZ1 CAR T cells significantly delayed tumor growth. Taken together, these results validate PTPRZ1 as a GBM target and prompt the clinical translation of anti-PTPRZ1 CAR T cells.

ICU-Electroencephalogram Unit Improves Outcome in Status Epilepticus Patients: A Retrospective Before-After Study.

OBJECTIVES: Continuous electroencephalogram (cEEG) monitoring is recommended for status epilepticus (SE) management in ICU but is still underused due to resource limitations and inconclusive evidence regarding its impact on outcome. Furthermore, the term "continuous monitoring" often implies continuous recording with variable intermittent review. The establishment of a dedicated ICU-electroencephalogram unit may fill this gap, allowing cEEG with nearly real-time review and multidisciplinary management collaboration. This study aimed to evaluate the effect of ICU-electroencephalogram unit establishing on SE outcome and management. DESIGN: Single-center retrospective before-after study. SETTING: Neuro-ICU of a Swiss academic tertiary medical care center. PATIENTS: Adult patients treated for nonhypoxic SE between November 1, 2015, and December 31, 2023. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Data from all SE patients were assessed, comparing those treated before and after ICU-electroencephalogram unit introduction. Primary outcomes were return to premorbid neurologic function, ICU mortality, SE duration, and ICU SE management. Secondary outcomes were SE type and etiology. Two hundred seven SE patients were included, 149 (72%) before and 58 (38%) after ICU-electroencephalogram unit establishment. ICU-electroencephalogram unit introduction was associated with increased detection of nonconvulsive SE ( p = 0.003) and SE due to acute symptomatic etiology ( p = 0.019). Regression analysis considering age, comorbidities, SE etiology, and SE semeiology revealed a higher chance of returning to premorbid neurologic function ( p = 0.002), reduced SE duration ( p = 0.024), and a shift in SE management with increased use of antiseizure medications ( p = 0.007) after ICU-electroencephalogram unit introduction. CONCLUSIONS: Integrating neurology expertise in the ICU setting through the establishment of an ICU-electroencephalogram unit with nearly real-time cEEG review, shortened SE duration, and increased likelihood of returning to premorbid neurologic function, with an increased number of antiseizure medications used. Further studies are warranted to validate these findings and assess long-term prognosis.

Ossification of Cranial Epidural Hematomas: A Systematic Review of Management Strategies and Presentation of an Illustrative Case.

The presence of a calcified or ossified chronic cranial epidural hematoma (EDH) is rare and has been described in only a few case reports in the literature. Consequently, clear treatment strategies remain elusive and may entail conservative and surgical approaches. In this study, we performed a systematic review of reported cases to evaluate the clinical course and treatment options for these patients. A comprehensive systematic search of two databases was performed, and information on patient characteristics, symptomatology, and treatment was extracted from eligible articles. A total of 56 cases were included in our analyses. Forty patients were male, 16 were female, with an average age of 21.38 years at the time of diagnosis. Assumed etiology was previous trauma in 35 cases, previous cranial surgery in 17 patients, and birth trauma and epidural bleeding after the utilization of the Mayfield clamp in 1 case each. The origin remained unclear in two cases. The time between trauma or surgery and diagnostics ranged between one and a half weeks and 50 years, with a median of 4 years (SD 9.8 years). The symptoms were very heterogeneous, ranging from acute neurological deterioration to chronic symptoms. In 15 cases, patients were asymptomatic, and cranial imaging was performed as part of a new trauma or a screening for other disease. Forty-one patients received surgical treatment by craniotomy and hematoma evacuation, and 13 patients were treated conservatively. In two cases, the liquid hematoma portion was aspirated through a burr hole. The localization of calcified or ossified EDH was mainly supratentorial. Young male patients most commonly present with calcified or ossified EDH after trauma, according to the epidemiological trend of acute EDH. Clinical presentation varies from asymptomatic to severe neurological deficits and signs of increased intracranial pressure. There is no standardized treatment; decisions must be made on an individual basis.

Single-cell atlas of the human brain vasculature across development, adulthood and disease.

A broad range of brain pathologies critically relies on the vasculature, and cerebrovascular disease is a leading cause of death worldwide. However, the cellular and molecular architecture of the human brain vasculature remains incompletely understood1. Here we performed single-cell RNA sequencing analysis of 606,380 freshly isolated endothelial cells, perivascular cells and other tissue-derived cells from 117 samples, from 68 human fetuses and adult patients to construct a molecular atlas of the developing fetal, adult control and diseased human brain vasculature. We identify extensive molecular heterogeneity of the vasculature of healthy fetal and adult human brains and across five vascular-dependent central nervous system (CNS) pathologies, including brain tumours and brain vascular malformations. We identify alteration of arteriovenous differentiation and reactivated fetal as well as conserved dysregulated genes and pathways in the diseased vasculature. Pathological endothelial cells display a loss of CNS-specific properties and reveal an upregulation of MHC class II molecules, indicating atypical features of CNS endothelial cells. Cell-cell interaction analyses predict substantial endothelial-to-perivascular cell ligand-receptor cross-talk, including immune-related and angiogenic pathways, thereby revealing a central role for the endothelium within brain neurovascular unit signalling networks. Our single-cell brain atlas provides insights into the molecular architecture and heterogeneity of the developing, adult/control and diseased human brain vasculature and serves as a powerful reference for future studies.

Hand Dystonia after Focused Ultrasound Thalamotomy in Essential Tremor.

INTRODUCTION: Magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy is an effective treatment for drug-resistant tremor. The most frequent side effects are ataxia, gait disturbance, paresthesias, dysgeusia, and hemiparesis. Here, we report the first case of thalamic hand dystonia rapidly occurring after MRgFUS thalamotomy of the ventral intermediate nucleus (V.im). CASE PRESENTATION: MRgFUS thalamotomy was performed in a 60-year-old left-handed patient for his disabling medically refractory essential tremor. The intervention resulted in a marked reduction of his action tremor. However, the patient developed an unvoluntary abnormal posture in his left hand a few days after the procedure with difficulty holding a cigarette between his fingers. Brain MRI revealed the expected MRgFUS lesion within the right V.im as well as an extension of the lesion anteriorly to the V.im in the ventro-oralis nucleus. Tractography showed that the lesion disrupted the dentato-rubro-thalamic tract as expected with a lesion suppressing tremor. However, the lesion also was interrupted fibers connecting to the superior frontal and pre-central cortices (primary motor cortex, premotor cortex, and supplementary area). We hypothesized that the interventional MRgFUS thalamotomy was slightly off target, which induced a dysfunction within the cortico-striato-thalamo-cortical network and the cerebello-thalamo-cortical pathway reaching a sufficient threshold of basal ganglia/cerebellum circuitry interference to induce dystonia. CONCLUSION: This rare side effect emphasizes the risk of imbalance within the dystonia network (i.e., basal ganglia-cerebello-thalamo-cortical circuit) secondary to V.im thalamotomy.

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.

Involvement of the contralateral hippocampus in ictal-like but not interictal epileptic activities in the kainate mouse model of temporal lobe epilepsy.

OBJECTIVE: Animal and human studies have shown that the seizure-generating region is vastly dependent on distant neuronal hubs that can decrease duration and propagation of ongoing seizures. However, we still lack a comprehensive understanding of the impact of distant brain areas on specific interictal and ictal epileptic activities (e.g., isolated spikes, spike trains, seizures). Such knowledge is critically needed, because all kinds of epileptic activities are not equivalent in terms of clinical expression and impact on the progression of the disease. METHODS: We used surface high-density electroencephalography and multisite intracortical recordings, combined with pharmacological silencing of specific brain regions in the well-known kainate mouse model of temporal lobe epilepsy. We tested the impact of selective regional silencing on the generation of epileptic activities within a continuum ranging from very transient to more sustained and long-lasting discharges reminiscent of seizures. RESULTS: Silencing the contralateral hippocampus completely suppresses sustained ictal activities in the focus, as efficiently as silencing the focus itself, but whereas focus silencing abolishes all focus activities, contralateral silencing fails to control transient spikes. In parallel, we observed that sustained focus epileptiform discharges in the focus are preceded by contralateral firing and more strongly phase-locked to bihippocampal delta/theta oscillations than transient spiking activities, reinforcing the presumed dominant role of the contralateral hippocampus in promoting long-lasting, but not transient, epileptic activities. SIGNIFICANCE: Altogether, our work provides suggestive evidence that the contralateral hippocampus is necessary for the interictal to ictal state transition and proposes that crosstalk between contralateral neuronal activity and ipsilateral delta/theta oscillation could be a candidate mechanism underlying the progression from short- to long-lasting epileptic activities.

Decompressive craniectomy plus best medical treatment versus best medical treatment alone for spontaneous severe deep supratentorial intracerebral haemorrhage: a randomised controlled clinical trial.

BACKGROUND: It is unknown whether decompressive craniectomy improves clinical outcome for people with spontaneous severe deep intracerebral haemorrhage. The SWITCH trial aimed to assess whether decompressive craniectomy plus best medical treatment in these patients improves outcome at 6 months compared to best medical treatment alone. METHODS: In this multicentre, randomised, open-label, assessor-blinded trial conducted in 42 stroke centres in Austria, Belgium, Finland, France, Germany, the Netherlands, Spain, Sweden, and Switzerland, adults (18-75 years) with a severe intracerebral haemorrhage involving the basal ganglia or thalamus were randomly assigned to receive either decompressive craniectomy plus best medical treatment or best medical treatment alone. The primary outcome was a score of 5-6 on the modified Rankin Scale (mRS) at 180 days, analysed in the intention-to-treat population. This trial is registered with ClincalTrials.gov, NCT02258919, and is completed. FINDINGS: SWITCH had to be stopped early due to lack of funding. Between Oct 6, 2014, and April 4, 2023, 201 individuals were randomly assigned and 197 gave delayed informed consent (96 decompressive craniectomy plus best medical treatment, 101 best medical treatment). 63 (32%) were women and 134 (68%) men, the median age was 61 years (IQR 51-68), and the median haematoma volume 57 mL (IQR 44-74). 42 (44%) of 95 participants assigned to decompressive craniectomy plus best medical treatment and 55 (58%) assigned to best medical treatment alone had an mRS of 5-6 at 180 days (adjusted risk ratio [aRR] 0·77, 95% CI 0·59 to 1·01, adjusted risk difference [aRD] -13%, 95% CI -26 to 0, p=0·057). In the per-protocol analysis, 36 (47%) of 77 participants in the decompressive craniectomy plus best medical treatment group and 44 (60%) of 73 in the best medical treatment alone group had an mRS of 5-6 (aRR 0·76, 95% CI 0·58 to 1·00, aRD -15%, 95% CI -28 to 0). Severe adverse events occurred in 42 (41%) of 103 participants receiving decompressive craniectomy plus best medical treatment and 41 (44%) of 94 receiving best medical treatment. INTERPRETATION: SWITCH provides weak evidence that decompressive craniectomy plus best medical treatment might be superior to best medical treatment alone in people with severe deep intracerebral haemorrhage. The results do not apply to intracerebral haemorrhage in other locations, and survival is associated with severe disability in both groups. FUNDING: Swiss National Science Foundation, Swiss Heart Foundation, Inselspital Stiftung, and Boehringer Ingelheim.

Current and Future Applications of Arterial Spin Labeling MRI in Cerebral Arteriovenous Malformations.

Arterial spin labeling (ASL) has emerged as a promising noninvasive tool for the evaluation of both pediatric and adult arteriovenous malformations (AVMs). This paper reviews the advantages and challenges associated with the use of ASL in AVM assessment. An assessment of the diagnostic workup of AVMs and their variants in both adult and pediatric populations is proposed. Evaluation after treatments, whether endovascular or microsurgical, was similarly examined. ASL, with its endogenous tracer and favorable safety profile, offers functional assessment and arterial feeder identification. ASL has demonstrated strong performance in identifying feeder arteries and detecting arteriovenous shunting, although some studies report inferior performance compared with digital subtraction angiography (DSA) in delineating venous drainage. Challenges include uncertainties in sensitivity for specific AVM features. Detecting AVMs in challenging locations, such as the apical cranial convexity, is further complicated, demanding careful consideration due to the risk of underestimating total blood flow. Navigating these challenges, ASL provides a noninvasive avenue with undeniable merits, but a balanced approach considering its limitations is crucial. Larger-scale prospective studies are needed to comprehensively evaluate the diagnostic performance of ASL in AVM assessment.

Clustering Functional Magnetic Resonance Imaging Time Series in Glioblastoma Characterization: A Review of the Evolution, Applications, and Potentials.

In this paper, we discuss how the clustering analysis technique can be applied to analyze functional magnetic resonance imaging (fMRI) time-series data in the context of glioblastoma (GBM), a highly heterogeneous brain tumor. The precise characterization of GBM is challenging and requires advanced analytical approaches. We have synthesized the existing literature to provide an overview of how clustering algorithms can help identify unique patterns within the dynamics of GBM. Our review shows that the clustering of fMRI time series has great potential for improving the differentiation between various subtypes of GBM, which is pivotal for developing personalized therapeutic strategies. Moreover, this method proves to be effective in capturing temporal changes occurring in GBM, enhancing the monitoring of disease progression and response to treatment. By thoroughly examining and consolidating the current research, this paper contributes to the understanding of how clustering techniques applied to fMRI data can refine the characterization of GBM. This article emphasizes the importance of incorporating cutting-edge data analysis techniques into neuroimaging and neuro-oncology research. By providing a detailed perspective, this approach may guide future investigations and boost the development of tailored therapeutic strategies for GBM.

The spectrum of acute and chronic consequences of neurotrauma in professional and amateur boxing - A call to action is advocated to better understand and prevent this phenomenon.

Introduction: Despite changes in regulations, boxing-related injuries and fatalities are still occurring. The numbers available in the literature regarding mortality and long-term consequences may not accurately represent the actual situation. Indeed, the real extent of this phenomenon remains poorly known. Research question: Delineating the spectrum of acute and chronic consequences of boxing-related traumatic brain injuries (TBI). Material and methods: Narrative review of the literature concerning acute and chronic boxing-related TBI. Keywords such as mortality, boxing, subdural hematoma were used to search in PubMed and Google scholar. An updated analysis of the Velazquez fatalities collection in boxing was undertaken. Results: The Velazquez collection includes 2076 fatalities from 1720 to the present with a death rate of 10 athletes per year. More than half of the deaths (N = 1354, 65.2%) occurred after a knock-out, and nearly 75% happened during professional bouts. In Australia, from 1832 to 2020, 163 fatalities were recorded (75% professional). In Japan, from 1952 to 2016, 38 deaths were recorded with a mean age of 23.9 years. Up to 40% of retired professional boxers in the United States were diagnosed with symptoms of chronic brain injury. Clinical dementia is far more prevalent among professional boxers than in amateurs with an incidence of 20%. Discussion and conclusions: A concerted effort to raise awareness and shed light on boxing-related neuro-trauma is required. Similar considerations can be made for other combat sports or contact sports. A call to action to address this knowledge gap, decrease and prevent this phenomenon is advocated.

Functional hemispheric disconnection procedures for chronic epilepsy: history, indications, techniques, complications and current practice in Europe. A consensus statement on behalf of the EANS functional neurosurgery section.

Introduction: The surgical procedure for severe, drug-resistant, unilateral hemispheric epilepsy is challenging. Over the last decades the surgical landscape for hemispheric disconnection procedures changed from anatomical hemispherectomy to functional hemispherotomy with a reduction of complications and stable good seizure outcome. Here, a task force of European epilepsy surgeons prepared, on behalf of the EANS Section for Functional Neurosurgery, a consensus statement on different aspects of the hemispheric disconnection procedure. Research question: To determine history, indication, timing, techniques, complications and current practice in Europe for hemispheric disconnection procedures in drug-resistant epilepsy. Material and methods: Relevant literature on the topic was collected by a literature search based on the PRISMA 2020 guidelines. Results: A comprehensive overview on the historical development of hemispheric disconnection procedures for epilepsy is presented, while discussing indications, timing, surgical techniques and complications. Current practice for this procedure in European epilepsy surgery centers is provided. At present, our knowledge of long-term seizure outcomes primarily stems from open surgical disconnection procedures. Although minimal invasive surgical techniques in epilepsy are rapidly developing and reported in case reports or small case series, long-term seizure outcome remain uncertain and needs to be reported. Discussion and conclusion: This is the first paper presenting a European consensus statement regarding history, indications, techniques and complications of hemispheric disconnection procedures for different causes of chronic, drug-resistant epilepsy. Furthermore, it serves as the pioneering document to report a comprehensive overview of the current surgical practices regarding this type of surgery employed in renowned epilepsy surgery centers across Europe.

Intracranial Epidermoid Cyst: A Volumetric Study of a Surgically Challenging Benign Lesion.

BACKGROUND: Intracranial epidermoid cysts are rare, benign tumors. Nevertheless, the microsurgical removal of these cysts is challenging. This is due to their capacity to adhere to the neurovascular tissue, as well as the associated difficulties in microsurgically peeling off their capsular wall hidden in dead angles. To better understand the rate of recurrence after surgical intervention, we have performed preoperative and postoperative volumetric analysis of epidermoid cysts, allowing the estimation of their growth rate after resection. METHODS: Imaging data from 22 patients diagnosed and surgically treated for an intracranial epidermoid cyst between 2000 and 2022 were retrospectively collected from 2 European neurosurgical centers with microsurgical expertise. Volumetric analysis was performed on magnetic resonance imaging data. RESULTS: Average cyst volume at diagnosis, before any surgery, measured in 12 patients was 28,877.6 ± 10,250.4 mm3 (standard error of the mean [SEM]). Estimated growth rate of incompletely resected epidermoids after surgery was 1,630.05 mm3 ± 729.95 (SEM). Assuming linear growth dynamics and normalizing to postoperative residual volume, the average postoperative growth rate corresponded to 61.5% ± 34.3% (SEM) of the postoperative residual volume per year. We observed signs of recurrence during a radiologic follow-up period of 6.0 ± 2.8 years (standard deviation) in more than 50% of our patients. CONCLUSIONS: Due to their slow-growing nature, epidermoid cysts can often reach a complex multicompartmental size before resection, even in young patients, thus requiring complex approaches with challenging capsular resection, which implies a high risk of nerve and vascular injury per se. Tumor recurrence may be predicted on the basis of postoperative volumetry.

Swiss trial of decompressive craniectomy versus best medical treatment of spontaneous supratentorial intracerebral haemorrhage (SWITCH): an international, multicentre, randomised-controlled, two-arm, assessor-blinded trial.

RATIONALE: Decompressive craniectomy (DC) is beneficial in people with malignant middle cerebral artery infarction. Whether DC improves outcome in spontaneous intracerebral haemorrhage (ICH) is unknown. AIM: To determine whether DC without haematoma evacuation plus best medical treatment (BMT) in people with ICH decreases the risk of death or dependence at 6 months compared to BMT alone. METHODS AND DESIGN: SWITCH is an international, multicentre, randomised (1:1), two-arm, open-label, assessor-blinded trial. Key inclusion criteria are age ⩽75 years, stroke due to basal ganglia or thalamic ICH that may extend into cerebral lobes, ventricles or subarachnoid space, Glasgow coma scale of 8-13, NIHSS score of 10-30 and ICH volume of 30-100 mL. Randomisation must be performed <66 h after onset and DC <6 h after randomisation. Both groups will receive BMT. Participants randomised to the treatment group will receive DC of at least 12 cm in diameter according to institutional standards. SAMPLE SIZE: A sample of 300 participants randomised 1:1 to DC plus BMT versus BMT alone provides over 85% power at a two-sided alpha-level of 0.05 to detect a relative risk reduction of 33% using a chi-squared test. OUTCOMES: The primary outcome is the composite of death or dependence, defined as modified Rankin scale score 5-6 at 6 months. Secondary outcomes include death, functional status, quality of life and complications at 180 days and 12 months. DISCUSSION: SWITCH will inform physicians about the outcomes of DC plus BMT in people with spontaneous deep ICH, compared to BMT alone. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02258919.

Mixed reality compared to the traditional ex cathedra format for neuroanatomy learning: the value of a three-dimensional virtual environment to better understand the real world.

OBJECTIVE: Neuroanatomy comprehension is a keystone of understanding intracranial surgeries. Traditionally taught to students during ex cathedra courses, neuroanatomy is described as complex. Mixed reality (MxR) opens new perspectives in the learning process. This study aims to compare MxR-based courses with traditional ex cathedra lectures for neuroanatomy education. METHODS: Two lectures describing the neuroanatomy of the anterior circulation arteries ("Vascular Lecture" [VS]) and important white matter fiber tracts ("White Fibers Lecture" [WF]) were designed and delivered in ex cathedra and MxR-based formats with the same audio content. Ninety-one medical students were randomly assigned to group A (ex cathedra WF/MxR VS) or group B (MxR WF/ex cathedra VS). The MxR content was delivered via MxR goggles. Prior to each lecture, students took a 10-item multiple choice question (MCQ) pretest. After the lectures, students took a 20-item MCQ posttest (75% neuroanatomy, 25% clinical correlation). RESULTS: The pretest scores showed no statistical difference between groups. Median posttest scores increased by 14.3% after using the MxR-based format compared to the ex cathedra format (16.00 [13.0, 18.0] vs 14.0 [11.0, 17.0], respectively, p < 0.01). Regarding the VS, students scored 21.7% better using the MxR format compared to the ex cathedra format (14.0 [12.0, 16.0] vs 11.5 [10.0, 14.0], p < 0.001). Concerning the WF, the median score using MxR was 18.0 (17.0, 19.0), and the median score using the ex cathedra format was 17.0 (16.0, 18.0; p < 0.01). Students showed high motivation to learn neuroanatomy in the future using MxR (74%) rather than ex cathedra format (25%; p < 0.001). Mild discomfort using the MxR goggles was reported by 48.3% of participants. Most participants (95.5%) preferred the MxR-based teaching. CONCLUSIONS: Students acquired a better knowledge of the anatomy of the anterior circulation arteries and white fiber tracts using MxR-based teaching as compared to the standard ex cathedra format. The perception of lecture quality and learning motivation was better using MxR-based teaching despite some mild discomfort. The development of MxR-based solutions is promising to improve neuroanatomy education.

Yield of non-invasive imaging in MRI-negative focal epilepsy.

OBJECTIVE: The absence of MRI-lesion reduces considerably the probability of having an excellent outcome (International League Against Epilepsies [ILAE] class I-II) after epilepsy surgery. Surgical success in magnetic-resonance imaging (MRI)-negative cases relies therefore mainly on non-invasive techniques such as positron-emission tomography (PET), subtraction ictal/inter-ictal single-photon-emission-computed-tomography co-registered to MRI (SISCOM), electric source imaging (ESI) and morphometric MRI analysis (MAP). We were interested in identifying the optimal imaging technique or combination to achieve post-operative class I-II in patients with MRI-negative focal epilepsy. METHODS: We identified 168 epileptic patients without MRI lesion. Thirty-three (19.6%) were diagnosed with unifocal epilepsy, underwent surgical resection and follow-up ⩾ 2 years. Sensitivity, specificity, predictive values, and diagnostic odds ratio (OR) were calculated for each technique individually and in combination (after co-registration). RESULTS: 23/33 (70%) were free of disabling seizures (75.0% with temporal and 61.5% extratemporal lobe epilepsy). None of the individual modalities presented an OR > 1.5, except ESI if only patients with interictal epileptiform discharges (IEDs) were considered (OR 3.2). On a dual combination, SISCOM with ESI presented the highest outcome (OR = 6). MAP contributed to detecting indistinguishable focal cortical dysplasia in particular in extratemporal epilepsies with a sensitivity of 75%. Concordance of PET, ESI on interictal epileptic discharges, and SISCOM was associated with the highest chance for post-operative seizure control (OR = 11). CONCLUSION: If MRI is negative, the chances to benefit from epilepsy surgery are almost as high as in lesional epilepsy, provided that multiple established non-invasive imaging tools are rigorously applied and co-registered together.