Enhancing medical students` confidence and performance in integrated structured clinical examinations (ISCE) through a novel near-peer, mixed model approach during the COVID-19 pandemic.

BACKGROUND: Near-peer medical education serves as an important method of delivering education to junior students by senior students. Due to the reduced clinical exposure because of the COVID-19 pandemic, we developed a mentorship scheme to help medical students with their Integrated Structured Clinical Examinations (ISCEs) by providing a combination of near-peer mentorship together with lecture-based teaching on a weekly basis for a 12-week period. Students attended a specialty-focused lecture every Tuesday followed by a small group teaching session organised by their tutor. METHODS: A longitudinal evaluative interventional study was undertaken by the international student led medical education organisation, OSCEazy. The teaching programme was organised and conducted by third year medical students to a recruited cohort of second year medical students. Students' perceptions of ISCEs (confidence, anxiety, and overall performance) were evaluated using 5-point Likert scales while their knowledge of the specialty was assessed using 10 single best answer questions which were distributed via Google® forms at the start and end of each week. In addition, we assessed tutor perceptions of their teaching and learning experience. RESULTS: Seventy-two tutees were enrolled in the programme (mean age: 24.4, female: 77.8%). 88.9% of the participants had not attended any online ISCE teaching prior to this. They preferred in-person ISCE teaching as compared to virtual sessions [median 4.5 (IQR 4-5) vs 3 (IQR 3-4), p <  0.0001), respectively]. There was a significant overall increase in knowledge when comparing pre-session and post-session performance [mean 53.7% vs 70.7%, p <  0.0001)]. There was a significant increase in student confidence [Confidence: median 3 (IQR:3-4) vs 4 (IQR 3-4), p <  0.0001] while no change was seen in the anxiety and perception of their overall performance in an ISCE. [Anxiety: median 3 (IQR 2-4) vs 3 (IQR 3-4), p = 0.37, Performance: median 3 (IQR 3-4) vs median 3 (IQR 3-4), p <  0.0001]. The tutors reported an increase in their confidence in teaching ISCEs online [median 3 (IQR 2-3.25) vs median 4 (IQR 4-5), p <  0.0001)]. CONCLUSION: Online near-peer teaching increases the confidence of both tutees and tutors involved while enhancing the tutees' knowledge of the specialty. Thus, medical schools should incorporate near-peer teaching in their curriculum to enhance the student learning experience.

Endovascular and surgical obliteration rates of spinal dural arteriovenous fistulae: a single UK Centre experience.

OBJECTIVE: Endovascular treatment (EVT) of spinal dural arteriovenous fistulae (SDAVF) has become increasingly popular given its less invasive nature. This study aims to assess radiological obliteration rates after surgery and EVT for SDAVF in a major tertiary referral centre serving a population of 2.2 million. METHOD: A retrospective review of all patients diagnosed with SDAVF between February 2010 and February 2018 was undertaken, identifying baseline demographics, treatment modality and the final radiological outcome (i.e., persistence of the SDAVF). Patients were identified from the departmental neurovascular database, clinical notes and imaging reports. RESULTS: Twenty patients were identified with an angiographically confirmed SDAVF. Two (10%) were managed conservatively. Nine patients (45%) underwent EVT. Obliteration was achieved in one patient (11%) after a single procedure, while one patient required two sessions. Further surgery was required in five patients (56%) to achieve complete obliteration. Nine patients (45%) underwent surgical disconnection as first treatment. Obliteration was radiologically confirmed in eight patients (89%). No radiological (MRI or angiographic) follow-up data was available for two patients (one from each group) and these were excluded from analysis. In this study, the obliteration rate of SDAVF after surgery was superior compared to EVT (p <0.01). CONCLUSION: Complete obliteration and recurrence rates after single treatment with EVT were inferior compared to surgical intervention. EVT may be better suited for specific presentations of SDAVF either in isolation or as an adjunct in multi-modality treatment. A national registry of outcomes may aid ongoing refinement of patient selection for EVT.

Asymptomatic chronic subdural haematoma - does it need neurosurgical intervention?

PURPOSE: Chronic subdural haematoma (CSDH) is a well-recognized consequence of head injury with a rising incidence worldwide. Whilst symptomatic CSDH warrants consideration of surgical intervention, the management of asymptomatic CSDH (AsCSDH) remains unclear. In this retrospective study, we investigate the natural history of AsCSDH, the requirement for radiological monitoring, and the role of neurosurgical input. METHODS: Head injury referrals to a tertiary neurosurgical unit over two years were screened to identify patients with AsCSDH. Clinical, radiological, and outcome parameters were collected for included patients. RESULTS: Of 2725 referrals, 106 (3.9%) patients were eligible for inclusion. The cohort consisted of predominantly male patients (70.8%) with an average age of 81.9 years and independent at baseline (79.3%). Radiological follow-up was recommended by neurosurgery in 4 patients (3.8%). Medical teams performed follow-up imaging for 57 patients (53.8%) culminating in a total of 116 follow-up scans, predominantly for falls or monitoring purposes. Antithrombotic agents were used by 61 patients (57.5%). Anticoagulants were held in 26/37 patients (70.3%) and antiplatelets in 12/29 patients (41.4%), ranging from 7 to 16 days when specified. Only one patient required neurosurgical intervention at 3 months from the time of initial presentation after the development of symptoms. CONCLUSIONS: Patients with AsCSDH do not require neuroradiological follow-up or neurosurgical intervention in the majority of instances. Medical professionals should explain to patients, families, and caregivers that the isolated finding of CSDH is not necessarily a cause for concern but safety netting advice regarding AsCSDH should be provided.

Interleukin-6 as a prognostic biomarker of clinical outcomes after traumatic brain injury: a systematic review.

Traumatic brain injury (TBI) is a major cause of mortality and morbidity worldwide. There are currently no early biomarkers for prognosis in routine clinical use. Interleukin-6 (IL-6) is a potential biomarker in the context of the established role of neuroinflammation in TBI recovery. Therefore, a systematic review of the literature was performed to assess and summarise the evidence for IL-6 secretion representing a useful biomarker for clinical outcomes. A multi-database literature search between January 1946 and July 2021 was performed. Studies were included if they reported adult TBI patients with IL-6 concentration in serum, cerebrospinal fluid (CSF) and/or brain parenchyma analysed with respect to functional outcome and/or mortality. A synthesis without meta-analysis is reported. Fifteen studies were included, reporting 699 patients. Most patients were male (71.7%), and the pooled mean age was 40.8 years; 78.1% sustained severe TBI. Eleven studies reported IL-6 levels in serum, six in CSF and one in the parenchyma. Five studies on serum demonstrated higher IL-6 concentrations were associated with poorer outcomes, and five showed no signification association. In CSF studies, one found higher IL-6 levels were associated with poorer outcomes, one found them to predict better outcomes and three found no association. Greater parenchymal IL-6 was associated with better outcomes. Despite some inconsistency in findings, it appears that exaggerated IL-6 secretion predicts poor outcomes after TBI. Future efforts require standardisation of IL-6 measurement practices as well as assessment of the importance of IL-6 concentration dynamics with respect to clinical outcomes, ideally within large prospective studies. Prospero registration number: CRD42021271200.

Pre-operative dosing of dexamethasone for the management of children with posterior fossa tumours: are we getting it right?

INTRODUCTION: Posterior fossa (PF) tumours are associated with vasogenic oedema causing symptoms of raised intracranial pressure. Preoperatively this is managed with dexamethasone. To minimise steroid related complications, the lowest effective dose should be administered. No neurosurgical guidelines exist for pre-operative dosing of dexamethasone in PF tumours. METHODS: A retrospective review was performed of surgically managed cases for patients under 16 years of age between 2013 and 2018 to ascertain the initial dose of dexamethasone with symptomatic PF tumours. RESULTS: Thirty-six patients were identified of which 30 notes were available. Sixteen were male. Median age was 6 years (range 10 months - 15 years). Twenty-two (73%) were referrals from DGH and 8 (27%) presented to our neurosurgical centre. All patients presented with symptomatic PF tumours including headache (97%), vomiting (93%), gait disturbance (43%), and nystagmus (17%). Four (13%) had papilloedema. Average initial stat dexamethasone dose was 9.15 mg; 0.31 mg/kg (range 1-16.7 mg; 0.05 - 1.77 mg/kg). Stratified according to weight, average dose (and range) was 8.8 mg; 0.94 mg/kg (1-16.6 mg; 0.13 - 1.77 mg/kg) in those weighing <10 kg; 9.7 mg; 0.66 mg/kg (4-16.7 mg; 0.21 - 1.35 mg/kg) in 10-20 kg; 12.3 mg;0.52 mg/kg (8-16.7 mg; 0.27 - 0.73mg/kg) in 20-30 kg and 7.8 mg; 0.17mg/kg (2-16.7 mg; 0.0 - 0.39 mg/kg) in >30 kg up to a maximum of 16.6 mg in any 24h period. These results suggest that dosage was higher in those children weighing less. PPI was used in 24 (80%) of cases. All doses were reduced after review by the neurosurgical team and a PPI added. CONCLUSION: Pre-operative dexamethasone dosing does not always reflect the severity of clinical symptoms for PF tumours. Guidelines are required to correlate clinical symptoms with a suggested suitable dose of dexamethasone to prevent overdose and complications associated with corticosteroid use. We recommend a weight-based regimen as provided by the Food and Drug Administration. The current advice is for 0.02-0.3mg/kg/day in 3-4 divided doses.

IL-1ß and HMGB1 are anti-neurogenic to endogenous neural stem cells in the sclerotic epileptic human hippocampus.

BACKGROUND: The dentate gyrus exhibits life-long neurogenesis of granule-cell neurons, supporting hippocampal dependent learning and memory. Both temporal lobe epilepsy patients and animal models frequently have hippocampal-dependent learning and memory difficulties and show evidence of reduced neurogenesis. Animal and human temporal lobe epilepsy studies have also shown strong innate immune system activation, which in animal models reduces hippocampal neurogenesis. We sought to determine if and how neuroinflammation signals reduced neurogenesis in the epileptic human hippocampus and its potential reversibility. METHODS: We isolated endogenous neural stem cells from surgically resected hippocampal tissue in 15 patients with unilateral hippocampal sclerosis. We examined resultant neurogenesis after growing them either as neurospheres in an ideal environment, in 3D cultures which preserved the inflammatory microenvironment and/or in 2D cultures which mimicked it. RESULTS: 3D human hippocampal cultures largely replicated the cellular composition and inflammatory environment of the epileptic hippocampus. The microenvironment of sclerotic human epileptic hippocampal tissue is strongly anti-neurogenic, with sustained release of the proinflammatory proteins HMGB1 and IL-1ß. IL-1ß and HMGB1 significantly reduce human hippocampal neurogenesis and blockade of their IL-1R and TLR 2/4 receptors by IL1Ra and Box-A respectively, significantly restores neurogenesis in 2D and 3D culture. CONCLUSION: Our results demonstrate a HMGB1 and IL-1ß-mediated environmental anti-neurogenic effect in human TLE, identifying both the IL-1R and TLR 2/4 receptors as potential drug targets for restoring human hippocampal neurogenesis in temporal lobe epilepsy.

Dissociable effects of complement C3 and C3aR on survival and morphology of adult born hippocampal neurons, pattern separation, and cognitive flexibility in male mice.

Adult hippocampal neurogenesis (AHN) is a form of ongoing plasticity in the brain that supports specific aspects of cognition. Disruptions in AHN have been observed in neuropsychiatric conditions presenting with inflammatory components and are associated with impairments in cognition and mood. Recent evidence highlights important roles of the complement system in synaptic plasticity and neurogenesis during neurodevelopment and in acute learning and memory processes. In this work we investigated the impact of the complement C3/C3aR pathway on AHN and its functional implications for AHN-related behaviours. In C3-/- mice, we found increased numbers and accelerated migration of adult born granule cells, indicating that absence of C3 leads to abnormal survival and distribution of adult born neurons. Loss of either C3 or C3aR affected the morphology of immature neurons, reducing morphological complexity, though these effects were more pronounced in the absence of C3aR. We assessed functional impacts of the cellular phenotypes in an operant spatial discrimination task that assayed AHN sensitive behaviours. Again, we observed differences in the effects of manipulating C3 or C3aR, in that whilst C3aR-/- mice showed evidence of enhanced pattern separation abilities, C3-/- mice instead demonstrated impaired behavioural flexibility. Our findings show that C3 and C3aR manipulation have distinct effects on AHN that impact at different stages in the development and maturation of newly born neurons, and that the dissociable cellular phenotypes are associated with specific alterations in AHN-related behaviours.

Surgical site infection in paediatric posterior fossa surgery: does pathology matter?

OBJECTIVES: The aim of this study was to explore the rates and potential risks of surgical site infection (SSI) after posterior fossa surgery for tumour resection in children. METHODS: We retrospectively reviewed our local paediatric (age < 16 years) database for all cases of posterior fossa (PF) brain tumour surgery between November 2008 and November 2019. We collected patient demographics, tumour histology/location, and the event of postoperative surgical site infection. RESULTS: Overall, 22.1% (n=15) developed SSI out of sixty-eight children undergoing PF surgery for resection of brain tumours; 73.3% of them had a confirmed diagnosis of medulloblastoma. There was no statistically significant difference in the age (5.1 ± 0.60 vs. 6.2 ± 0.97 years; p=0.47) and duration of operation (262 vs. 253 min; p = 0.7655) between the medulloblastoma group and other tumours. Although the rate of postoperative hydrocephalus was higher in the medulloblastoma group (12.9% vs. 0%), this was not associated with increased SSI. Rates of CSF leak between the 2 groups were not different. CONCLUSION: Medulloblastoma as a pathological entity seems to carry higher risk of postoperative surgical site infection compared to other types of paediatric posterior fossa tumours. Further larger studies are required to look into this causal relationship and other risk factors that might be involved.

Clinical features associated with the development of hydrocephalus following TBI in the paediatric age group.

INTRODUCTION: Predictive factors for post-traumatic hydrocephalus (PTH) in adults have been elucidated but remain uncertain for children. We aimed to identify the prevalence of PTH in paediatric patients and identify clinical/radiological factors which may increase the probability of children developing PTH. METHODS: This was a retrospective study of all patients < 16 years old admitted to our unit with traumatic brain injury (TBI) between March 2013 and June 2018, 108 patients in total. Patients were classified as mild (13-15), moderate (9-12) or severe (3-8) TBI based on admission GCS. Three independent reviewers collected data from case notes. CT scans were reviewed for hydrocephalus using Evan's index. Two-tailed Fisher's exact tests with a p value < 0.05 were considered statistically significant. RESULTS: Median patient age was 7 years, and 65% were males (n = 70). PTH wasn't identified in any patients with mild/moderate TBI (n = 79). In cases of severe TBI (n = 29), three patients developed PTH requiring ventriculoperitoneal shunting (10%; p = 0.02). Radiological features which were significantly more common in the PTH group were intraventricular haemorrhage (p = 0.05) and subarachnoid haemorrhage (p = 0.03). There was also a trend towards a statistically significant association with subdural haematoma (p = 0.07). The need for other neurosurgical procedures, such as fracture elevation and craniotomy, did not increase the probability of developing with PTH (p = 0.08). DISCUSSION: The prevalence of PTH in our study is 2.7%. Factors which may be associated with a higher probability of developing PTH may include IVH, SAH, severity of TBI, and subdural haematoma. We propose a national prospective multicentre database of paediatric PTH. The data collected on prevalence, presentation, risk factors, and management could guide contemporary management and improve the outcomes of children with PTH.

The need for hair removal in paediatric brain tumour surgery?

INTRODUCTION: Preoperative hair removal is conventional practice within neurosurgery in an attempt to maintain antisepsis. However, there is a lack of evidence to suggest that it makes a difference with regards to infection. This article aims to relate preoperative hair removal to SSIs for paediatric patients. METHODS AND MATERIALS: A retrospective analysis was conducted from a single paediatric neurosurgical database at the University Hospital of Wales. Patients were grouped according to whether they underwent preoperative hair removal or not. Findings were reviewed in light of the previously published literature. RESULTS: One hundred eighty two paediatric intracranial tumours were operated on between November 2008 and 2019. A total of twenty-six patients (14%) developed an infection post-operatively, of which meningitis was the most common (77%). Eighty-nine operations were undertaken without preoperative hair removal, of which there were a total of fifteen infections (17%). In the hair removal group, there were a total of eleven infections out of ninety-three operations (12%). Overall, the patients without hair removal had a higher infection rate when compared to those with hair removal (17 and 12% respectively), however, this result was not statistically significant (p-value 0.3989). CONCLUSION: We did not find evidence that hair removal in paediatric neurosurgery effects postoperative infection risk.

Neurosurgery activity levels in the United Kingdom and republic of Ireland during the first wave of the covid-19 pandemic - a retrospective cross-sectional cohort study.

The impact of Covid-19 on surgical patients worldwide has been substantial. In the United Kingdom (UK) and the Republic of Ireland (RoI), the first wave of the pandemic occurred in March 2020. The aims of this study were to: (1) evaluate the volume of neurosurgical operative activity levels, Covid-19 infection rate and mortality rate in April 2020 with a retrospective cross-sectional cohort study conducted across 16 UK and RoI neurosurgical centres, and (2) compare patient outcomes in a single institution in April-June 2020 with a comparative cohort in 2019. Across the UK and RoI, 818 patients were included. There were 594 emergency and 224 elective operations. The incidence rate of Covid-19 infection was 2.6% (21/818). The overall mortality rate in patients with a Covid-19 infection was 28.6% (6/21). In the single centre cohort analysis, an overall reduction in neurosurgical operative activity by 65% was observed between 2020 (n = 304) and 2019 (n = 868). The current and future impact on UK neurosurgical operative activity has implications for service delivery and neurosurgical training.

Demographics, presentation, and clinical outcomes after traumatic bifrontal contusions: a systematic review.

Traumatic bifrontal contusions (TBC) form a recognised clinical entity among patients with traumatic brain injury (TBI). This study aims to systematically review current literature on demographics, management, and predictors of outcomes of patients with TBC. A multi-database literature search (PubMed, Cochrane, OVID Medline/Embase) was performed using PRISMA as a search strategy. Studies were selected by predefined selection criteria (PROSPERO: CRD42018055390), and risk of bias was assessed using an adapted form of ROBINS-I tool. Of the 275 studies yielded by the literature search, seven articles met the criteria for inclusion, all of which were level III evidence. Total cohort consisted of 468 patients; predominantly male (n = 5; 303/417 patients) with average age 44.3 years (range, 7-81). Falls (44.9%) and road traffic accidents (46.6%) were the commonest mechanisms of injury with an average presentation GCS of 9.2 (n = 3, 119 patients). GCS on admission of ≤ 13.1 and contusion volume at day 2 post-injury of ≥ 62.9cm3 were associated with increased risk of deterioration needing surgical interventions (n = 1, 7 patients). The majority of patients underwent surgery; the average GOS was 4, at an average follow-up duration of 11.7 months (n = 6, 356 patients). The currently available evidence on the management of TBC is scarce. Larger multicentre well-designed studies are needed to further delineate the factors behind acute deterioration, the effectiveness of management options. Once in place, this can be used to develop and test an algorithmic approach to management of TBC resulting in consistently improved outcomes.

C-reactive protein kinetics post elective cranial surgery. A prospective observational study.

Introduction: Post cranial surgery readmission, largely caused by surgical site infection (SSI), is a marker of patient-care quality requiring comprehensive discharge planning. Currently, discharge assessment is based on clinical recovery and basic laboratory tests, including C-reactive protein (CRP). Although CRP kinetics have been examined postoperatively in a handful of papers, the validity of CRP as a standalone test to predict SSI is yet to be explored.Methods: A prospective observational study was performed on adult patients undergoing elective cranial surgery over a 3-month period. Laboratory data; CRP, white cell count (WCC), neutrophil cell count (NCC), and clinical data were assessed pre and post-operatively and were evaluated as predictors for safe discharge. Readmission rates within 1 month were recorded.Results: In this study, 68 patients were included. About 8.6% were readmitted due to SSI. A postoperativepeak in CRP was seen on day 2 with a value of 57 in the non-readmitted group, and 115 in the readmitted group. CRP dropped gradually to normal levels by day 5 in the non-readmitted group. A secondary CRP rise at day 5 was noted in the readmitted group with a sensitivity, specificity, and negative predictive value of 71%, 90%, and 96%, respectively. Interestingly, our ROC analysis indicates that a CRP value of less than 65 predicts safe discharge with a sensitivity of 86%, specificity of 89% and negative predictive value of 98% of safe discharge (area under the curve, AUC: 0.782). No significant difference in other inflammatory markers was found between both groups.Conclusions: CRP increases postoperatively for 4-5 d which could be a physiological response to surgery, however, prolonged elevation or a secondary increase in CRP may indicate an ongoing infection. Our data validate the potential use of CRP levels to predict SSI. A multicentre study is warranted to investigate the role of CRP in predicting SSI.

The Effectiveness of Virtual Reality Interventions for Improvement of Neurocognitive Performance After Traumatic Brain Injury: A Systematic Review.

OBJECTIVE: To evaluate current evidence for the effectiveness of virtual reality (VR) interventions in improving neurocognitive performance in individuals who have sustained a traumatic brain injury (TBI). METHODS: A systematic literature search across multiple databases (PubMed, EMBASE, Web of Science) for articles of relevance. Studies were evaluated according to study design, patient cohort, VR intervention, neurocognitive parameters assessed, and outcome. VR interventions were evaluated qualitatively with respect to methodology and extent of immersion and quantitatively with respect to intervention duration. OUTCOMES: Our search yielded 324 articles, of which only 13 studies including 132 patients with TBI met inclusion criteria. A wide range of VR interventions and cognitive outcome measures is reported. Cognitive measures included learning and memory, attention, executive function, community skills, problem solving, route learning, and attitudes about driving. Several studies (n = 10) reported statistically significant improvements in outcome, and 2 studies demonstrated successful translation to real-life performance. CONCLUSIONS: VR interventions hold significant potential for improving neurocognitive performance in patients with TBI. While there is some evidence for translation of gains to activities of daily living, further studies are required to confirm the validity of cognitive measures and reliable translation to real-life performance.

Subdural haematoma in neonates following forceps-assisted delivery: case series and review of the literature.

PURPOSE: Subdural haematoma (SDH) is a recognised complication of forceps-assisted delivery (FAD). There are no guidelines regarding its management. This study aims to provide a better insight into the management and outcomes of neonatal SDH post-FAD. METHODS: Retrospective review of our neonatal database and systematic review of the literature for neonatal cases that presented with SDH after FAD. Retrospective neurosurgical database search for cases of neonatal SDH post-FAD managed in our unit between January 2007 and January 2017. Systematic review of the literature was performed using PRISMA guidelines. The inclusion criteria are as follows: (1) neonates; (2) forceps-assisted delivery; (3) evidence of SDH on imaging, with or without other traumatic lesions. RESULTS: A literature search yielded nine studies with 30 patients meeting our inclusion criteria. In addition, four cases were identified from our institutional database. Forty-two percent (n = 14) had their SDH managed surgically, with subsequent full neurological recovery in 57%. In comparison, 95% (n = 18) of the conservatively managed patients made a full recovery. Hydrocephalus was present in 1/19 and 11/14 of the conservatively managed and surgically managed patients respectively. CONCLUSIONS: Conservative management can lead to a full neurological recovery in SDH following FAD in neonates. However, a significant minority may still need neurosurgical intervention for the SDH or subsequent hydrocephalus; therefore, we advocate early transfer to a specialist neuroscience centre.

AMPA receptors and seizures mediate hippocampal radial glia-like stem cell proliferation.

Neurogenesis is sustained throughout life in the mammalian brain, supporting hippocampus-dependent learning and memory. Its permanent alteration by status epilepticus (SE) is associated with learning and cognitive impairments. The mechanisms underlying the initiation of altered neurogenesis after SE are not understood. Glial fibrillary acidic protein-positive radial glia (RG)-like cells proliferate early after SE, but their proliferation dynamics and signaling are largely unclear. We have previously reported a polarized distribution of AMPA receptors (AMPARs) on RG-like cells in vivo and postulated that these may signal their proliferation. Here, we examined the acute effects of kainate on hippocampal precursor cells in vitro and in kainate-induced SE on proliferating and quiescent clones of 5-bromo-2-deoxyuridine prelabeled hippocampal precursors in vivo. In vitro, we found that 5 µM kainate shortened the cell cycle time of RG-like cells via AMPAR activation and accelerated cell cycle re-entry of their progeny. It also shifted their fate choice expanding the population of RG-like cells and reducing the population of downstream amplifying neural progenitors. Kainate enhanced the survival of all precursor cell subtypes. Pharmacologically, kainate's proliferative and survival effects were abolished by AMPAR blockade. Functional AMPAR expression was confirmed on RG-like cells in vitro. In agreement with these observations, kainate/seizures enhanced the proliferation and expansion predominantly of constitutively cycling RG-like cell clones in vivo. Our results identify AMPARs as key potential players in initiating the proliferation of dentate RG-like cells and unravel a possible receptor target for modifying the radial glia-like cell response to SE.

Correction to: the role of the complement system in traumatic brain injury: a review.

After publication of the article [1], it was brought to our attention that Tables 1 and 2 were missing from the final manuscript, These tables can be seen below and have now been added to the revised version of the article.

The role of the complement system in traumatic brain injury: a review.

Traumatic brain injury (TBI) is an important cause of disability and mortality in the western world. While the initial injury sustained results in damage, it is the subsequent secondary cascade that is thought to be the significant determinant of subsequent outcomes. The changes associated with the secondary injury do not become irreversible until some time after the start of the cascade. This may present a window of opportunity for therapeutic interventions aiming to improve outcomes subsequent to TBI. A prominent contributor to the secondary injury is a multifaceted inflammatory reaction. The complement system plays a notable role in this inflammatory reaction; however, it has often been overlooked in the context of TBI secondary injury. The complement system has homeostatic functions in the uninjured central nervous system (CNS), playing a part in neurodevelopment as well as having protective functions in the fully developed CNS, including protection from infection and inflammation. In the context of CNS injury, it can have a number of deleterious effects, evidence for which primarily comes not only from animal models but also, to a lesser extent, from human post-mortem studies. In stark contrast to this, complement may also promote neurogenesis and plasticity subsequent to CNS injury. This review aims to explore the role of the complement system in TBI secondary injury, by examining evidence from both clinical and animal studies. We examine whether specific complement activation pathways play more prominent roles in TBI than others. We also explore the potential role of complement in post-TBI neuroprotection and CNS repair/regeneration. Finally, we highlight the therapeutic potential of targeting the complement system in the context of TBI and point out certain areas on which future research is needed.

Prospective, multicentre study of external ventricular drainage-related infections in the UK and Ireland.

OBJECTIVES: External ventricular drain (EVD) insertion is a common neurosurgical procedure. EVD-related infection (ERI) is a major complication that can lead to morbidity and mortality. In this study, we aimed to establish a national ERI rate in the UK and Ireland and determine key factors influencing the infection risk. METHODS: A prospective multicentre cohort study of EVD insertions in 21 neurosurgical units was performed over 6 months. The primary outcome measure was 30-day ERI. A Cox regression model was used for multivariate analysis to calculate HR. RESULTS: A total of 495 EVD catheters were inserted into 452 patients with EVDs remaining in situ for 4700 days (median 8 days; IQR 4-13). Of the catheters inserted, 188 (38%) were antibiotic-impregnated, 161 (32.5%) were plain and 146 (29.5%) were silver-bearing. A total of 46 ERIs occurred giving an infection risk of 9.3%. Cox regression analysis demonstrated that factors independently associated with increased infection risk included duration of EVD placement for ≥8 days (HR=2.47 (1.12-5.45); p=0.03), regular sampling (daily sampling (HR=4.73 (1.28-17.42), p=0.02) and alternate day sampling (HR=5.28 (2.25-12.38); p<0.01). There was no association between catheter type or tunnelling distance and ERI. CONCLUSIONS: In the UK and Ireland, the ERI rate was 9.3% during the study period. The study demonstrated that EVDs left in situ for ≥8 days and those sampled more frequently were associated with a higher risk of infection. Importantly, the study showed no significant difference in ERI risk between different catheter types.

Ruptured pseudoaneurysm as a cause of spontaneous intracerebral bleed in a 3-month old infant.

Ruptured intracranial aneurysms in infants are very rare but if missed can lead to poor outcomes. Spontaneously dissecting false aneurysms have been described only in a handful of cases. We report a case of a three-month old girl with deteriorating neurological function due to a ruptured distal middle cerebral artery pseudoaneurysm.