Traumatic brain injury: global collaboration for a global challenge

Current state of global neurosurgery activity amongst European neurosurgeons

BACKGROUND

The expanding field of global neurosurgery calls for a committed neurosurgical community to advocate for universal access to timely, safe, and affordable neurosurgical care for everyone, everywhere. The aim of this study was to assess the current state of global neurosurgery activity amongst European neurosurgeons and to identify barriers to involvement in global neurosurgery initiatives.

METHODS

Cross-sectional study through dissemination of a web-based survey, from September 2019 to January 2020, to collect data from European neurosurgeons at various career stages. Descriptive analysis was conducted on respondent data.

RESULTS

Three hundred and ten neurosurgeons from 40 European countries responded: 53.5% regularly follow global neurosurgery developments, and 29.4% had travelled abroad with a global neurosurgery collaborative, with 23.2% planning a future trip. Respondents from high income European countries predominantly travelled to Africa (41.6%) or Asia (34.4%), whereas respondents from middle income European countries frequently traversed Europe (63.2%) and North America (47.4%). Cost implications (66.5%) were the most common barrier to global neurosurgery activity, followed by interference with current practice (45.8%), family duties (35.2%), difficulties obtaining humanitarian leave (27.7%) and lack of international partners (27.4%). 86.8% would incorporate a global neurosurgery period within training programmes.

CONCLUSIONS

European neurosurgeons are interested in engaging in global neurosurgery partnerships, and several sustainable programs focused on local capacity building, education and research have been established over the last decade. However, individual and system barriers to engagement persist. We provided insight into these to allow development of tailored mechanisms to overcome such barriers, enabling European neurosurgeons to advocate for the Global Surgery 2030 goals.

Integrated Microfluidic-Transistor Sensing System for Multiplexed Detection of Traumatic Brain Injury Biomarkers

Traumatic brain injury (TBI) is widely recognized as a global public health crisis, affecting millions of people each year, leading to permanent neurologic, emotional, and occupational disability, and highlighting the urgent need for rapid, sensitive, and early assessment. Here, we design a novel and simple lithography-free method for preparing dual-channel graphene-based field-effect transistors (G-FETs) and integrating them with microfluidic channels for simultaneously multiplexed detection of key blood TBI biomarkers: neurofilament light chain (NFL) and glial fibrillary acidic protein (GFAP). The G-FET utilizes an ingenious dual-channel electrode array design, where the source is shared between channels and the drains are independent of each other, which is the key to achieving simultaneous output of dual detection signals. At the same time, the microfluidic chip realizes microscale fluidic control and fast sample response time. This integrated detection system shows excellent sensitivity in biological fluids for the TBI biomarkers with detection limits as low as 55.63 fg/mL for NFL and 144.45 fg/mL for GFAP in phosphate-buffered saline (PBS) buffer, respectively. Finally, the clinical sample analysis shows promising performance for TBI detection, with an area under the curve (AUC) of 0.98 for the two biomarkers. And the combined dual-protein assay is also a good predictor of intracranial injury findings on computed tomography (CT) scans (AUC = 0.907). The integrated microfluidic G-FET device with a dual-signal output strategy has important potential for application in clinical practice, providing more comprehensive information for brain injury assessment.

Extended tests for evaluating post-traumatic brain injury deficits in resource-limited settings: methods and pilot study data

Introduction

Traumatic brain injury (TBI) is one of the leading causes of all injury-related deaths and disabilities in the world, especially in low to middle-income countries (LMICs) which also suffer from lower levels of funding for all levels of the health care system for patients suffering from TBI. These patients do not generally get comprehensive diagnostic workup, monitoring, or treatment, and return to work too quickly, often with undiagnosed post-traumatic deficits which in turn can lead to subsequent incidents of physical harm.

Methods

Here, we share methods and results from our research project to establish innovative, simple, and scientifically based practices that dramatically leverage technology and validated testing strategies to identify post-TBI deficits quickly and accurately, to circumvent economic realities on the ground in LMICs. We utilized paper tests such as the Montreal cognitive assessment (MoCA), line-bisection, and Bell's test. Furthermore, we combined modifications of neuroscience computer tasks to aid in assessing peripheral vision, memory, and analytical accuracies. Data from seventy-one subjects (51 patients and 20 controls, 15 females and 56 males) from 4 hospitals in Ethiopia are presented. The traumatic brain injury group consists of 17 mild, 28 moderate, and 8 severe patients (based on the initial Glasgow Comma Score). Controls are age and education-matched subjects (no known history of TBI, brain lesions, or spatial neglect symptoms).

Results

We found these neurophysiological methods can: 1) be implemented in LMICs and 2) test impairments caused by TBI, which generally affect brain processing speed, memory, and both executive and cognitive controls.

Discussion

The main findings indicate that these examinations can identify several deficits, especially the MoCA test. These tests show great promise to assist in the evaluation of TBI patients and support the establishment of dedicated rehabilitation centers. Our next steps will be expansion of the cohort size and application of the tests to other settings.

Anti-inflammatory effect and mechanism of catalpol in various inflammatory diseases

Catalpol is a kind of iridoid glucoside, widely found in a variety of plants, mostly extracted from the rhizome of the traditional medicinal herb rehmanniae. It has various biological activities such as anti-inflammatory, antioxidant, and antitumor. The anti-inflammatory effects of catalpol have been demonstrated in a variety of diseases, such as neurological diseases, atherosclerosis, renal diseases, respiratory diseases, digestive diseases, bone and joint diseases, eye diseases, and periodontitis. The purpose of this review is to summarize the existing literature on the anti-inflammatory effects of catalpol in a variety of inflammatory diseases over the last decade and to focus on the anti-inflammatory mechanisms of catalpol.

Intracranial pressure monitoring in the perioperative period of patients with acute liver failure undergoing orthotopic liver transplantation

Acute liver failure (ALF) may result in severe neurological complications caused by cerebral edema and elevated intracranial pressure (ICP). Multiple pathogenic mechanisms explain the elevated ICP, and newer hypotheses have been described. While invasive ICP monitoring (ICPM) may have a role in ALF management, these patients are typically coagulopathic and at risk for intracranial hemorrhage. ICPM is the subject of much debate, and significant heterogeneity exists in clinical practice regarding its use. Contemporary ICPM techniques and coagulopathy reversal strategies may be associated with a lower risk of hemorrhage; however, most of the evidence is limited by its retrospective nature and relatively small sample size.

The role of neurosurgery in advancing pediatric CNS tumor care worldwide

Introduction

There is substantial inequity in survival outcomes for pediatric brain tumor patients residing in high-income countries (HICs) compared to low- and middle-income countries (LMICs). To address disparities in pediatric cancer survival, the World Health Organization (WHO) established the Global Initiative for Childhood Cancer (GICC) to expand quality care for children with cancer.

Research question

To provide an overview of pediatric neurosurgical capacity and detail the burden of neurosurgical diseases impacting children.

Material and methods

A narrative review of the current context of global pediatric neurosurgical capacity as it relates to neurooncology and other diseases relevant to children.

Results

In this article, we provide an overview of pediatric neurosurgical capacity and detail the burden of neurosurgical diseases impacting children. We highlight concerted advocacy and legislative efforts aimed at addressing unmet neurosurgical needs in children. Finally, we discuss the potential implications of advocacy efforts on treating pediatric CNS tumors and outline strategies to improve global outcomes for children with brain tumors worldwide in the context of the WHO GICC.

Discussion and conclusion

With both global pediatric oncology and neurosurgical initiatives converging on the treatment of pediatric brain tumors, significant strides toward decreasing the burden of pediatric neurosurgical diseases will hopefully be made.

Overexpression of GPX4 attenuates cognitive dysfunction through inhibiting hippocampus ferroptosis and neuroinflammation after traumatic brain injury

Ferroptosis is a newly discovered form of regulated cell death that is triggered primarily by lipid peroxidation. A growing body of evidence has implicated ferroptosis in the pathophysiology of traumatic brain injury (TBI). However, none of these studies focused its role on TBI-induced hippocampal injury. Here, we demonstrated that the distinct ferroptotic signature was detected in the injured hippocampus at the early stage of TBI. Besides, a prominent pro-ferroptosis environment was detected in the ipsilateral hippocampus after TBI, including elevated levels of arachidonic acid (AA), ACLS4, and ALXO15, and deficiency of GPX4. Subsequently, we used AAV-mediated Gpx4 overexpression to counteract ferroptosis in the hippocampus, and found that TBI-induced cognitive deficits were significantly alleviated after Gpx4 overexpression. Biochemical results also confirmed that TBI-induced hippocampal ferroptosis and synaptic damage were partially reversed by Gpx4 overexpression. In addition, Gpx4 overexpression inhibited TBI-induced neuroinflammation and peripheral macrophage infiltration. Interestingly, the results of transwell migration assay showed that ferroptotic neurons increased CCL2 expression and promoted iBMDM cell migration. However, this effect was inhibited by CCL2 antagonist, RS102895. These data suggested that inhibition of ferroptosis may be as a potential strategy to ameliorate TBI-induced cognitive deficits through blockade of hippocampal ferroptosis and neuroinflammation.

Catalpol Ameliorates Oxidative Stress and Neuroinflammation after Traumatic Brain Injury in Rats

Oxidative stress and neuroinflammation are deemed the prime causes of neurological damage after traumatic brain injury (TBI). Catalpol, an active ingredient of Rehmannia glutinosa, has been suggested to possess antioxidant and anti-inflammatory properties. This study was designed to investigate the protective effects of catalpol against TBI and the underlying mechanisms of action of catalpol. A rat model of TBI was induced by controlled cortical impact. Catalpol (10 mg/kg) or vehicle was administered via intravenous injection 1 h post trauma and then once daily for 3 consecutive days. Following behavioural tests performed 72 h after TBI, the animals were sacrificed and pericontusional areas of the brain were collected for neuropathological experiments and analysis. Treatment with catalpol significantly ameliorated neurological impairment, blood-brain barrier disruption, cerebral oedema, and neuronal apoptosis after TBI (P < 0.05). Catalpol also attenuated TBI-induced oxidative insults, as evidenced by reduced reactive oxygen species generation; decreased malondialdehyde levels; and enhanced superoxide dismutase, catalase and glutathione peroxidase activity (P < 0.05). Catalpol promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 and the expression of its downstream antioxidant enzyme HO-1 following TBI (P < 0.05). Moreover, catalpol treatment markedly inhibited posttraumatic microglial activation and neutrophil infiltration, suppressed NLRP3 inflammasome activation and reduced the production of the proinflammatory cytokine IL-1β (P < 0.05). Taken together, these findings reveal that catalpol provides neuroprotection against oxidative stress and neuroinflammation after TBI in rats. Therefore, catalpol may be a novel treatment strategy for TBI patients.

TrkB agonist N-acetyl serotonin promotes functional recovery after traumatic brain injury by suppressing ferroptosis via the PI3K/Akt/Nrf2/Ferritin H pathway

Ferroptosis is a form of regulated cell death that is mainly triggered by iron-dependent lipid peroxidation. A growing body of evidence suggests that ferroptosis is involved in the pathophysiology of traumatic brain injury (TBI), and tropomyosin-related kinase B (TrkB) deficiency would mediate TBI pathologies. As an agonist of TrkB and an immediate precursor of melatonin, N-acetyl serotonin (NAS) exerts several beneficial effects on TBI, but there is no information regarding the role of NAS in ferroptosis after TBI. Here, we examined the effect of NAS treatment on TBI-induced functional outcomes and ferroptosis. Remarkably, the administration of NAS alleviated TBI-induced neurobehavioral deficits, lesion volume, and neurodegeneration. NAS also rescued TBI-induced mitochondrial shrinkage, the changes in ferroptosis-related molecule expression, and iron accumulation in the ipsilateral cortex. Similar results were obtained with a well-established ferroptosis inhibitor, liproxstatin-1. Furthermore, NAS activated the TrkB/PI3K/Akt/Nrf2 pathway in the mouse model of TBI, while inhibition of PI3K and Nrf2 weakened the protection of NAS against ferroptosis both in vitro and in vivo, suggesting that a possible pathway linking NAS to the action of anti-ferroptosis was TrkB/PI3K/Akt/Nrf2. Given that ferritin H (Fth) is a known transcription target of Nrf2, we then investigated the effects of NAS on neuron-specific Fth knockout (Fth-KO) mice. Strikingly, Fth deletion almost abolished the protective effects of NAS against TBI-induced ferroptosis and synaptic damage, although Fth deletion-induced susceptibility toward ferroptosis after TBI was reversed by an iron chelator, deferoxamine. Taken together, these data indicate that the TrkB agonist NAS treatment appears to improve brain function after TBI by suppressing ferroptosis, at least in part, through activation of the PI3K/Akt/Nrf2/Fth pathway, providing evidence that NAS is likely to be a promising anti-ferroptosis agent for further treatment for TBI.

A Machine Learning Approach for the Prediction of Severe Acute Kidney Injury Following Traumatic Brain Injury

BACKGROUND

Acute kidney injury (AKI), a prevalent non-neurological complication following traumatic brain injury (TBI), is a major clinical issue with an unfavorable prognosis. This study aimed to develop and validate machine learning models to predict severe AKI (stage 3 or greater) incidence in patients with TBI.

METHODS

A retrospective cohort study was conducted by using two public databases: the Medical Information Mart for Intensive Care IV (MIMIC)-IV and the eICU Collaborative Research Database (eICU-CRD). Recursive feature elimination was used to select candidate predictors obtained within 24 h of intensive care unit admission. The area under the curve and decision curve analysis curves were used to determine the discriminatory ability. On the other hand, the calibration curve was employed to evaluate the calibrated performance of the newly developed machine learning models.

RESULTS

In the MIMIC-IV database, there were 808 patients diagnosed with moderate and severe TBI (msTBI) (msTBI is defined as Glasgow Coma Score < 12). Of these, 60 (7.43%) patients experienced severe AKI. External validation in the eICU-CRD indicated that the random forest (RF) model had the highest area under the curve of 0.819 (95% confidence interval 0.783-0.851). Furthermore, in the calibration curve, the RF model was well calibrated (P = 0.795).

CONCLUSIONS

In this study, the RF model demonstrated better discrimination in predicting severe AKI than other models. An online calculator could facilitate its application, potentially improving the early detection of severe AKI and subsequently improving the clinical outcomes among patients with msTBI.

Neurotrauma clinicians’ perspectives on the contextual challenges associated with traumatic brain injury follow up in low-income and middle-income countries: A reflexive thematic analysis

Background

Traumatic brain injury (TBI) is a major global health issue, but low- and middle-income countries (LMICs) face the greatest burden. Significant differences in neurotrauma outcomes are recognised between LMICs and high-income countries. However, outcome data is not consistently nor reliably recorded in either setting, thus the true burden of TBI cannot be accurately quantified.

Objective

To explore the specific contextual challenges of, and possible solutions to improve, long-term follow-up following TBI in low-resource settings.

Methods

A cross-sectional, pragmatic qualitative study, that considered knowledge subjective and reality multiple (i.e. situated within the naturalistic paradigm). Data collection utilised semi-structured interviews, by videoconference and asynchronous e-mail. Data were analysed using Braun and Clarke’s six-stage Reflexive Thematic Analysis.

Results

18 neurosurgeons from 13 countries participated in this study, and data analysis gave rise to five themes: Clinical Context: What must we understand?; Perspectives and Definitions: What are we talking about?; Ownership and Beneficiaries: Why do we do it?; Lost to Follow-up: Who misses out and why?; Processes and Procedures: What do we do, or what might we do?

Conclusion

The collection of long-term outcome data plays an imperative role in reducing the global burden of neurotrauma. Therefore, this was an exploratory study that examined the contextual challenges associated with long-term follow-up in LMICs. Where technology can contribute to improved neurotrauma surveillance and remote assessment, these must be implemented in a manner that improves patient outcomes, reduces clinical burden on physicians, and does not surpass the comprehension, capabilities, or financial means of the end user. Future research is recommended to investigate patient and family perspectives, the impact on clinical care teams, and the full economic implications of new technologies for follow-up.

The Application of Guideline-Based Care for Traumatic Brain and Spinal Cord Injury in Low- and Middle-Income Countries: A Provider-Based Survey

Objective

Neurosurgical guidelines have resulted in improved clinical outcomes and more optimized care for many complex neurosurgical pathologies. As momentum in global neurosurgical efforts has grown, there is little understanding about the application of these guidelines in low- and middle-income countries.

Methods

A 29-question survey was developed to assess the application of specific recommendations from neurosurgical brain and spinal cord injury guidelines. Surveys were distributed to an international cohort of neurosurgeons and neurotrauma stakeholders.

Results

A total of 82 of 222 (36.9%) neurotrauma providers responded to the survey. The majority of respondents practiced in low- and middle-income countries settings (49/82, 59.8%). There was a significantly greater mean traumatic brain injury volume in low-income countries (56% ± 13.5) and middle-income countries (46.5% ± 21.3) compared with high-income countries (27.9% ± 13.2), P < 0.001. Decompressive hemicraniectomy was estimated to occur in 61.5% (±30.8) of cases of medically refractory intracranial pressure with the lowest occurrence in the African region (44% ± 37.5). The use of prehospital cervical immobilization varied significantly by income status, with 36% (±35.6) of cases in low-income countries, 52.4% (±35.5) of cases in middle-income countries, and 95.2% (±10) in high-income countries, P < 0.001. Mean arterial pressure elevation greater than 85 mm Hg to improve spinal cord perfusion was estimated to occur in 71.7% of cases overall with lowest occurrence in Eastern Mediterranean region (55.6% ± 24).

Conclusions

While some disparities in guideline implementation are inevitably related to the availability of clinical resources, other differences could be more quickly improved with accessibility of current evidence-based guidelines and development of local data.

Delivering Large-Scale Neurosurgical Studies in the UK: The Impact of Trainees

The UK neurosurgical community has a track record of delivering high-quality, practice-changing clinical research studies, facilitated by a robust clinical research infrastructure and close collaborations between neurosurgical centers. More recently, these large-scale studies have been conceived, developed, and delivered by neurosurgical trainees, working under the umbrella of the British Neurosurgical Trainee Research Collaborative (BNTRC). In this paper, we outline the current landscape of large-scale neurosurgical studies in the UK, focusing on the role of trainees in facilitating this research. Importantly, we focus on our experience of trainee-led studies, including the development of the network, current challenges, and future directions. We believe that a similar model can be applied in different settings and countries, which will drive up the quality of neurosurgical research, ultimately benefiting future neurosurgical patients.

Rubiano A, G. Kolias A, Silva Paiva W. Evaluation of Computed Tomography Scoring Systems in the Prediction of Short-Term Mortality in Traumatic Brain Injury Patients from a Low- to Middle-Income Country

The present study aims to evaluate the accuracy of the prognostic discrimination and prediction of the short-term mortality of the Marshall computed tomography (CT) classification and Rotterdam and Helsinki CT scores in a cohort of TBI patients from a low- to middle-income country. This is a post hoc analysis of a previously conducted prospective cohort study conducted in a university-associated, tertiary-level hospital that serves a population of >12 million in Brazil. Marshall CT class, Rotterdam and Helsinki scores, and their components were evaluated in the prediction of 14-day and in-hospital mortality using Nagelkerk's pseudo-R² and area under the receiver operating characteristic curve. Multi-variate regression was performed using known outcome predictors (age, Glasgow Coma Scale, pupil response, hypoxia, hypotension, and hemoglobin values) to evaluate the increase in variance explained when adding each of the CT classification systems. Four hundred forty-seven patients were included. Mean age of the patient cohort was 40 (standard deviation, 17.83) years, and 85.5% were male. Marshall CT class was the least accurate model, showing pseudo-R² values equal to 0.122 for 14-day mortality and 0.057 for in-hospital mortality, whereas Rotterdam CT scores were 0.245 and 0.194 and Helsinki CT scores were 0.264 and 0.229. The AUC confirms the best prediction of the Rotterdam and Helsinki CT scores regarding the Marshall CT class, which presented greater discriminative ability. When associated with known outcome predictors, Marshall CT class and Rotterdam and Helsinki CT scores showed an increase in the explained variance of 2%, 13.4%, and 21.6%, respectively. In this study, Rotterdam and Helsinki scores were more accurate models in predicting short-term mortality. The study denotes a contribution to the process of external validation of the scores and may collaborate with the best risk stratification for patients with this important pathology.

Edonerpic maleate regulates glutamate receptors through CRMP2- and Arc-mediated mechanisms in response to brain trauma

Dysfunction of ionotropic glutamate receptors (iGluRs) is a key molecular mechanism of excitotoxic neuronal injury following traumatic brain injury (TBI). Edonerpic maleate is a low molecular-weight compound that was screened as a candidate neuroprotective agent. In this study, we investigated its effects on TBI and GluRs signaling. Traumatic neuronal injury (TNI) induced by scratch followed by glutamate treatment was performed to mimic TBI in vitro. Edonerpic maleate at 1 and 10 μM exerted protective activity when it was added within 2 h following injury. The protective activities were also confirmed by the reduction of lipid peroxidation and oxidative stress. In addition, edonerpic maleate inhibited the expression of surface NR2B, total GluR1, and surface GluR1, and mitigated the intracellular Ca²⁺ responses following injury in vitro. Western blot analysis showed that edonerpic maleate reduced the cleavage of collapsing response mediator protein 2 (CRMP2), but increased the expression of postsynaptic protein Arc. By using gene overexpression and silencing technologies, CRMP2 was overexpressed and Arc was knockdown in cortical neurons. The results showed that the effect of edonerpic maleate on NMDA receptor expression was mediated by CRMP2, whereas the edonerpic maleate-induced AMPA receptor regulation was dependent on Arc activation. In in vivo TBI model, 30 mg/kg edonerpic maleate alleviated the TBI-induced brain edema, neuronal loss, and microglial activation, with no effect on locomotor function at 24 h. However, edonerpic maleate improves long-term neurological function after TBI. Furthermore, edonerpic maleate inhibited CRMP2 cleavage but increased Arc activation in vivo. In summary, our results identify edonerpic maleate as a clinically potent small compound with which to attenuate TBI-related brain damage through regulating GluRs signaling.

PD-L1 signaling in reactive astrocytes counteracts neuroinflammation and ameliorates neuronal damage after traumatic brain injury

BACKGROUND

Tissue damage and cellular destruction are the major events in traumatic brain injury (TBI), which trigger sterile neuroimmune and neuroinflammatory responses in the brain. While appropriate acute and transient neuroimmune and neuroinflammatory responses facilitate the repair and adaptation of injured brain tissues, prolonged and excessive neuroimmune and neuroinflammatory responses exacerbate brain damage. The mechanisms that control the intensity and duration of neuroimmune and neuroinflammatory responses in TBI largely remain elusive.

METHODS

We used the controlled cortical impact (CCI) model of TBI to study the role of immune checkpoints (ICPs), key regulators of immune homeostasis, in the regulation of neuroimmune and neuroinflammatory responses in the brain in vivo.

RESULTS

We found that de novo expression of PD-L1, a potent inhibitory ICP, was robustly and transiently induced in reactive astrocytes, but not in microglia, neurons, or oligodendrocyte progenitor cells (OPCs). These PD-L1⁺ reactive astrocytes were highly enriched to form a dense zone around the TBI lesion. Blockade of PD-L1 signaling enlarged brain tissue cavity size, increased infiltration of inflammatory Ly-6C^High monocytes/macrophages (M/Mɸ) but not tissue-repairing Ly-6C^LowF4/80⁺ M/Mɸ, and worsened TBI outcomes in mice. PD-L1 gene knockout enhanced production of CCL2 that is best known for its ability to interact with its cognate receptor CCR2 on Ly-6C^High M/Mϕ to chemotactically recruit these cells into inflammatory sites. Mechanically, PD-L1 signaling in astrocytes likely exhibits dual inhibitory activities for the prevention of excessive neuroimmune and neuroinflammatory responses to TBI through (1) the PD-1/PD-L1 axis to suppress the activity of brain-infiltrating PD-1⁺ immune cells, such as PD-1⁺ T cells, and (2) PD-L1 intrinsic signaling to regulate the timing and intensity of astrocyte reactions to TBI.

CONCLUSIONS

PD-L1⁺ astrocytes act as a gatekeeper to the brain to control TBI-related neuroimmune and neuroinflammatory responses, thereby opening a novel avenue to study the role of ICP-neuroimmune axes in the pathophysiology of TBI and other neurological disorders.

rhFGF20 promotes angiogenesis and vascular repair following traumatic brain injury by regulating Wnt/β-catenin pathway

The pathology of cerebrovascular disorders takes an important role in traumatic brain injury (TBI) by increasing intracranial pressure. Fibroblast growth factor 20 (FGF20) is a brain-derived neurotrophic factor, that has been shown to play an important role in the survival of dopaminergic neurons and the treatment of Parkinson's disease (PD). However, little is known about the role of FGF20 in the treatment of TBI and its underlying mechanism. The purpose of this study was to evaluate the protective effect of recombinant human FGF20 (rhFGF20) on protecting cerebral blood vessels after TBI. In this study, we indicated that rhFGF20 could reduce brain edema, Evans blue penetration and upregulated the expression of blood-brain barrier (BBB)-related tight junction (TJ) proteins, exerting a protective effect on the BBB in vivo after TBI. In the TBI repair phase, rhFGF20 promoted angiogenesis, neurological and cognitive function recovery. In tumor necrosis factor-α (TNF-α)-induced human brain microvascular endothelial cells (hCMEC/D3), an in vitro BBB disruption model, rhFGF20 reversed the impairment in cell migration and tube formation induced by TNF-α. Moreover, in both the TBI mouse model and the in vitro model, rhFGF20 increased the expression of β-catenin and GSK3β, which are the two key regulators in the Wnt/β-catenin signaling pathway. In addition, the Wnt/β-catenin inhibitor IWR-1-endo significantly reversed the effects of rhFGF20. These results indicate that rhFGF20 may prevent vascular repair and angiogenesis through the Wnt/β-catenin pathway.

Catalytically active gold clusters with atomic precision for noninvasive early intervention of neurotrauma

Background

Neurotrauma is a worldwide public health problem which can be divided into primary and secondary damge. The primary damge is caused by external forces and triggers the overproduction of peroxides and superoxides, leading to long-lasting secondary damage including oxidative stress, wound infection and immunological reactions. The emerging catalysts have shown great potential in the treatment of brain injury and neurogenic inflammation, but are limited to biosafety issues and delivery efficiency.

Results

Herein, we proposed the noninvasive delivery route to brain trauma by employing highly active gold clusters with enzyme-like activity to achieve the early intervention. The decomposition rate to H₂O₂ of the ultrasmall gold clusters is 10 times that of glassy carbon (GC) electrodes, indicating excellent catalytic activity. The gold clusters can relieve the oxidative stress and decrease the excessive O₂^·− and H₂O₂ both in vitro and in vivo. Besides, gold clusters can accelerate the wound healing of brain trauma and alleviate inflammation via inhibiting the activation of astrocytes and microglia through noninvasive adminstration. decrease the peroxide and superoxide of brain tissue.

Conclusions

Present work shows noninvasive treatment is a promising route for early intervention of brain trauma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01071-4.

Neurosurgeons' experiences of conducting and disseminating clinical research in low-income and middle-income countries: a reflexive thematic analysis

OBJECTIVES

Low-income and-middle-income countries (LMICs) are increasing investment in research and development, yet there remains a paucity of neurotrauma research published by those in LMICs. The aim of this study was to understand neurosurgeons' experiences of, aspirations for, and ability to conduct and disseminate clinical research in LMICs.

DESIGN

This was a two-stage inductive qualitative study situated within the naturalistic paradigm. This study committed to an interpretivist way of knowing (epistemology), and considered reality subjective and multiple (ontology). Data collection used online methods and included a web-based survey tool for demographic data, an asynchronous online focus group and follow-up semistructured interviews. Data were analysed using Braun and Clarke's Reflexive Thematic Analysis supported by NVivo V.12.

SETTING

LMICs.

PARTICIPANTS

In April-July 2020, 26 neurosurgeons from 11 LMICs participated in this study (n=24 in the focus groups, n=20 in follow-up interviews).

RESULTS

The analysis gave rise to five themes: The local landscape; creating capacity; reach and impact; collaborative inquiry; growth and sustainability. Each theme contained an inhibitor and stimulus to neurosurgeons conducting and disseminating clinical research, interpreted as 'the neurosurgical research potential in LMICs'. Mentorship, education, infrastructure, impact and engagement were identified as specific accelerators. Whereas lack of generalisability, absence of dissemination and dissemination without peer review may desensitise the impact of research conducted by neurosurgeons.

CONCLUSION

The geographical, political and population complexities make research endeavour challenging for neurosurgeons in LMICs. Yet in spite of, and because of, these complexities LMICs provide rich opportunities to advance global neurosurgery. More studies are required to evaluate the specific effects of accelerators of research conducted by neurosurgeons and to understand the effects of desensitisers on high-quality, high-impact clinical research.

Management of severe traumatic brain injury in regions with limited resources

IMPORTANCE

Severe traumatic brain injury (sTBI) is a critical health problem in regions of limited resources (RLRs). Younger populations are among the most impacted. The objective of this review is to analyze recent consensus-based algorithms, protocols and guidelines proposed for the care of patients with TBI in RLRs.

OBSERVATIONS

The principal mechanisms for sTBI in RLRs are road traffic injuries (RTIs) and violence. Limitations of care include suboptimal or non-existent pre-hospital care, overburdened emergency services, lack of trained human resources, and surgical and intensive care. Low-cost neuromonitoring systems are currently in testing, and formal neurotrauma registries are forming to evaluate both long-term outcomes and best practices at every level of care from hospital transport to the emergency department (ED), to the operating room and intensive care unit (ICU).

CONCLUSIONS AND RELEVANCE

The burden of sTBI is highest in RLRs. As working-age adults are the predominantly affected age-group, an increase in disability-adjusted life years (DALYs) generates a loss of economic growth in regions where economic growth is needed most. Four multi-institutional collaborations between high-income countries (HICs) and LMICs have developed evidence and consensus-based documents focused on capacity building for sTBI care as a means of addressing this substantial burden of disease.

Epidemiology of traumatic brain injury based on clinical symptoms amongst inhabitants of the Southwest Region of Cameroon: a community-based study

BACKGROUND

The majority of studies investigating the epidemiology of traumatic brain injury (TBI) in sub-Saharan Africa are primarily hospital-based, missing fatal, mild, and other cases of TBI that do not present to formal care settings. This study aims to bridge this gap in data by describing the epidemiology of TBI in the Southwest Region of Cameroon.

METHODS

This was a cross-sectional community-based study. Using a three-stage cluster sampling, local research assistants surveyed households with a pre-tested questionnaire to identify individuals with symptoms of TBI in nine health districts in the Southwest Region of Cameroon from 2016 to 2017.

RESULTS

Data gathered on 8,065 individuals revealed 78 cases of suspected TBI. Road traffic injury (RTI) comprised 55% of subjects' mechanism of injury. Formal medical care was sought by 82.1% of subjects; three subjects died at the time of injury. Following injury, 59% of subjects reported difficulty affording basic necessities and 87.2% of subjects were unable to perform activities of their primary occupation.

CONCLUSIONS

This study postulates an incidence of TBI in Southwest Cameroon of 975.57 per 100,000 individuals, significantly greater than prior findings. A large proportion of TBI is secondary to RTI.

International Neurotrauma Training Based on North-South Collaborations: Results of an Inter-institutional Program in the Era of Global Neurosurgery

Objective: Shortage of general neurosurgery and specialized neurotrauma care in low resource settings is a critical setback in the national surgical plans of low and middle-income countries (LMIC). Neurotrauma fellowship programs typically exist in high-income countries (HIC), where surgeons who fulfill the requirements for positions regularly stay to practice. Due to this issue, neurosurgery residents and medical students from LMICs do not have regular access to this kind of specialized training and knowledge-hubs. The objective of this paper is to present the results of a recently established neurotrauma fellowship program for neurosurgeons of LMICs in the framework of global neurosurgery collaborations, including the involvement of specialized parallel education for neurosurgery residents and medical students. Methods: The Global Neurotrauma Fellowship (GNTF) program was inaugurated in 2015 by a multi-institutional collaboration between a HIC and an LMIC. The course organizers designed it to be a 12-month program based on adapted neurotrauma international competencies with the academic support of the Barrow Neurological Institute at Phoenix Children's Hospital and Meditech Foundation in Colombia. Since 2018, additional support from the UK, National Institute of Health Research (NIHR) Global Health Research in Neurotrauma Project from the University of Cambridge enhanced the infrastructure of the program, adding a research component in global neurosurgery and system science. Results: Eight fellows from Brazil, Venezuela, Cuba, Pakistan, and Colombia have been trained and certified via the fellowship program. The integration of international competencies and exposure to different systems of care in high-income and low-income environments creates a unique environment for training within a global neurosurgery framework. Additionally, 18 residents (Venezuela, Colombia, Ecuador, Peru, Cuba, Germany, Spain, and the USA), and ten medical students (the United Kingdom, USA, Australia, and Colombia) have also participated in elective rotations of neurotrauma and critical care during the time of the fellowship program, as well as in research projects as part of an established global surgery initiative. Conclusion: We have shown that it is possible to establish a neurotrauma fellowship program in an LMIC based on the structure of HIC formal training programs. Adaptation of the international competencies focusing on neurotrauma care in low resource settings and maintaining international mentoring and academic support will allow the participants to return to practice in their home-based countries.

Long-Term Outcome After Decompressive Craniectomy in a Developing Country

BACKGROUND

Decompressive craniectomy (DC) may reduce mortality but might increase the number of survivors in a vegetative state. In this study, we assessed the long-term functional outcome of patients undergoing DC in a middle-income country.

METHODS

This was a prospective observational study of patients undergoing DC at a single tertiary hospital in southern Brazil between January 2015 and December 2018.

RESULTS

Of the 125 patients who were included in this study, 57.6% (72/125) had a traumatic brain injury (TBI), 21.6% (27/125) had a stroke, 19.2% (24/125) had a cerebral hemorrhage (intracerebral or subarachnoid hemorrhage), and 0.8% (1/125) had a cerebral abscess. The mean age was 45.18 ± 19.6 years, and 71% of the patients were men. The mean initial Glasgow Coma Scale (GCS) score was 7.8 ± 3.6. The in-hospital mortality rate was 44.8% (56/125). Of the survivors, 50.7% (35/69) had a favorable outcome 6 months after DC. After multivariate analysis, a lower initial GCS score (7.5 ± 3.6 versus 8.8 ± 3.5, P = 0.007) and older age (49.7 ± 18.9 versus 33.3 ± 16.2 years, P = 0.0001) were associated with an unfavorable outcome.

CONCLUSION

Six months after DC, almost half of the patients who survive have a favorable outcome.

Mismatch between midline shift and hematoma thickness as a prognostic factor of mortality in patients sustaining acute subdural hematoma

Background

Acute subdural hematoma (ASDH) is a traumatic lesion commonly found secondary to traumatic brain injury. Radiological findings on CT, such as hematoma thickness (HT) and structures midline shift (MLS), have an important prognostic role in this disease. The relationship between HT and MLS has been rarely studied in the literature. Thus, this study aimed to assess the prognostic accuracy of the difference between MLS and HT for acute outcomes in patients with ASDH in a low-income to middle-income country.

Methods

This was a post-hoc analysis of a prospective cohort study conducted in a university-associated tertiary-level hospital in Brazil. The TRIPOD (Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis) statement guidelines were followed. The difference values between MLS and HT (Zumkeller index, ZI) were divided into three categories (<0.00, 0.01–3, and >3). Logistic regression analyses were performed to reveal the OR of categorized ZI in predicting primary outcome measures. A Cox regression was also performed and the results were presented through HR. The discriminative ability of three multivariate models including clinical and radiological variables (ZI, Rotterdam score, and Helsinki score) was demonstrated.

Results

A total of 114 patients were included. Logistic regression demonstrated an OR value equal to 8.12 for the ZI >3 category (OR 8.12, 95% CI 1.16 to 40.01; p=0.01), which proved to be an independent predictor of mortality in the adjusted model for surgical intervention, age, and Glasgow Coma Scale (GCS) score. Cox regression analysis demonstrated that this category was associated with 14-day survival (HR 2.92, 95% CI 1.38 to 6.16; p=0.005). A multivariate analysis performed for three models including age and GCS with categorized ZI or Helsinki or Rotterdam score demonstrated area under the receiver operating characteristic curve values of 0.745, 0.767, and 0.808, respectively.

Conclusions

The present study highlights the potential usefulness of the difference between MLS and HT as a prognostic variable in patients with ASDH.

Level of evidence

Level III, epidemiological study.

Cell Proliferation in the Piriform Cortex of Rats with Motor Cortex Ablation Treated with Growth Hormone and Rehabilitation

Traumatic brain injury represents one of the main health problems in developed countries. Growth hormone (GH) and rehabilitation have been claimed to significantly contribute to the recovery of lost motor function after acquired brain injury, but the mechanisms by which this occurs are not well understood. In this work, we have investigated cell proliferation in the piriform cortex (PC) of adult rats with ablation of the frontal motor cortex treated with GH and rehabilitation, in order to evaluate if this region of the brain, related to the sense of smell, could be involved in benefits of GH treatment. Male rats were either ablated the frontal motor cortex in the dominant hemisphere or sham-operated and treated with GH or vehicle at 35 days post-injury (dpi) for five days. At 36 dpi, all rats received daily injections of bromodeoxyuridine (BrdU) for four days. We assessed motor function through the paw-reaching-for-food task. GH treatment and rehabilitation at 35 dpi significantly improved the motor deficit caused by the injury and promoted an increase of cell proliferation in the PC ipsilateral to the injury, which could be involved in the improvement observed. Cortical ablation promoted a greater number of BrdU+ cells in the piriform cortex that was maintained long-term, which could be involved in the compensatory mechanisms of the brain after injury.

Neurotrauma clinicians' perspectives on the contextual challenges associated with long-term follow-up following traumatic brain injury in low-income and middle-income countries: a qualitative study protocol

INTRODUCTION

Traumatic brain injury (TBI) is a global public health concern; however, low/middle-income countries (LMICs) face the greatest burden. The WHO recognises the significant differences between patient outcomes following injuries in high-income countries versus those in LMICs. Outcome data are not reliably recorded in LMICs and despite improved injury surveillance data, data on disability and long-term functional outcomes remain poorly recorded. Therefore, the full picture of outcome post-TBI in LMICs is largely unknown.

METHODS AND ANALYSIS

This is a cross-sectional pragmatic qualitative study using individual semistructured interviews with clinicians who have experience of neurotrauma in LMICs. The aim of this study is to understand the contextual challenges associated with long-term follow-up of patients following TBI in LMICs. For the purpose of the study, we define 'long-term' as any data collected following discharge from hospital. We aim to conduct individual semistructured interviews with 24-48 neurosurgeons, beginning February 2020. Interviews will be recorded and transcribed verbatim. A reflexive thematic analysis will be conducted supported by NVivo software.

ETHICS AND DISSEMINATION

The University of Cambridge Psychology Research Ethics Committee approved this study in February 2020. Ethical issues within this study include consent, confidentiality and anonymity, and data protection. Participants will provide informed consent and their contributions will be kept confidential. Participants will be free to withdraw at any time without penalty; however, their interview data can only be withdrawn up to 1 week after data collection. Findings generated from the study will be shared with relevant stakeholders such as the World Federation of Neurosurgical Societies and disseminated in conference presentations and journal publications.

Development and assessment of competency-based neurotrauma course curriculum for international neurosurgery residents and neurosurgeons

OBJECTIVE

Traumatic brain injuries (TBIs) are a significant disease burden worldwide. It is imperative to improve neurosurgeons' training during and after their medical residency with appropriate neurotrauma competencies. Unfortunately, the development of these competencies during neurosurgeons' careers and in daily practice is very heterogeneous. This article aimed to describe the development and evaluation of a competency-based international course curriculum designed to address a broad spectrum of needs for taking care of patients with neurotrauma with basic and advanced interventions in different scenarios around the world.

METHODS

A committee of 5 academic neurosurgeons was involved in the task of building this course curriculum. The process started with the identification of the problems to be addressed and the subsequent performance needed. After this, competencies were defined. In the final phase, educational activities were designed to achieve the intended learning outcomes. In the end, the entire process resulted in competency and outcomes-based education strategy, including a definition of all learning activities and learning outcomes (curriculum), that can be integrated with a faculty development process, including training. Further development was completed by 4 additional academic neurosurgeons supported by a curriculum developer specialist and a project manager. After the development of the course curriculum, template programs were developed with core and optional content defined for implementation and evaluation.

RESULTS

The content of the course curriculum is divided into essentials and advanced concepts and interventions in neurotrauma care. A mixed sample of 1583 neurosurgeons and neurosurgery residents attending 36 continuing medical education activities in 30 different cities around the world evaluated the course. The average satisfaction was 97%. The average usefulness score was 4.2, according to the Likert scale.

CONCLUSIONS

An international competency-based course curriculum is an option for creating a well-accepted neurotrauma educational process designed to address a broad spectrum of needs that a neurotrauma practitioner faces during the basic and advanced care of patients in different regions of the world. This process may also be applied to other areas of the neurosurgical knowledge spectrum. Moreover, this process allows worldwide standardization of knowledge requirements and competencies, such that training may be better benchmarked between countries regardless of their income level.

Deletion of ferritin H in neurons counteracts the protective effect of melatonin against traumatic brain injury-induced ferroptosis

Accumulating evidence demonstrates that ferroptosis may be important in the pathophysiological process of traumatic brain injury (TBI). As a major hormone of the pineal gland, melatonin exerts many beneficial effects on TBI, but there is no information regarding the effects of melatonin on ferroptosis after TBI. As expected, TBI resulted in the time-course changes of ferroptosis-related molecules expression and iron accumulation in the ipsilateral cortex. Importantly, we found that treating with melatonin potently rescued TBI induced the changes mentioned above and improved functional deficits versus vehicle. Similar results were obtained with a ferroptosis inhibitor, liproxstatin-1. Moreover, the protective effect of melatonin is likely dependent on melatonin receptor 1B (MT2). Although ferritin plays a vital role in iron metabolism by storing excess cellular iron, its precise function in the brain, and whether it involves melatonin's neuroprotection remain unexplored. Considering ferritin H (Fth) is expressed predominantly in the neurons and global loss of Fth in mice induces early embryonic lethality, we then generated neuron-specific Fth conditional knockout (Fth-KO) mice, which are viable and fertile but have altered iron metabolism. In addition, Fth-KO mice were more susceptible to ferroptosis after TBI, and the neuroprotection by melatonin was largely abolished in Fth-KO mice. In vitro siFth experiments further confirmed the results mentioned above. Taken together, these data indicate that melatonin produces cerebroprotection, at least partly by inhibiting neuronal Fth-mediated ferroptosis following TBI, supporting the notion that melatonin is an excellent ferroptosis inhibitor and its anti-ferroptosis provides a potential therapeutic target for treating TBI.

Neurosurgical Randomized Trials in Low- and Middle-Income Countries

BACKGROUND

The setting of a randomized trial can determine whether its findings are generalizable and can therefore apply to different settings. The contribution of low- and middle-income countries (LMICs) to neurosurgical randomized trials has not been systematically described before.

OBJECTIVE

To perform a systematic analysis of design characteristics and methodology, funding source, and interventions studied between trials led by and/or conducted in high-income countries (HICs) vs LMICs.

METHODS

From January 2003 to July 2016, English-language trials with >5 patients assessing any one neurosurgical procedure against another procedure, nonsurgical treatment, or no treatment were retrieved from MEDLINE, Scopus, and Cochrane Library. Income classification for each country was assessed using the World Bank Atlas method.

RESULTS

A total of 73.3% of the 397 studies that met inclusion criteria were led by HICs, whereas 26.7% were led by LMICs. Of the 106 LMIC-led studies, 71 were led by China. If China is excluded, only 8.8% were led by LMICs. HIC-led trials enrolled a median of 92 patients vs a median of 65 patients in LMIC-led trials. HIC-led trials enrolled from 7.6 sites vs 1.8 sites in LMIC-led studies. Over half of LMIC-led trials were institutionally funded (54.7%). The majority of both HIC- and LMIC-led trials evaluated spinal neurosurgery, 68% and 71.7%, respectively.

CONCLUSION

We have established that there is a substantial disparity between HICs and LMICs in the number of published neurosurgical trials. A concerted effort to invest in research capacity building in LMICs is an essential step towards ensuring context- and resource-specific high-quality evidence is generated.

Dexmedetomidine inhibits inflammatory response and autophagy through the circLrp1b/miR-27a-3p/Dram2 pathway in a rat model of traumatic brain injury

Circular RNAs (circRNAs) have a regulatory function on inflammation and autophagy, of which rno-circRNA_010705 (circLrp1b) appears to be significantly up-regulated following traumatic brain injury (TBI). Dexmedetomidine (DEX) shows improvement effects in TBI by inhibiting NLRP3/caspase-1. However, whether circLrp1b plays critical roles in DEX-mediated TBI attenuation and the underlying mechanisms remain unclear. After TBI was established in rats by controlled cortical impact (CCI) to cause brain trauma, they received an intracerebroventricular injection of lentiviral vector, followed by intraperitoneal injection of DEX. Administration of DEX ameliorated autophagy in rats following TBI, accompanied by up-regulated circLrp1b and Dram2 and down-regulated miR-27a-3p. DEX promoted the effects of circLrp1b in attenuating TBI-induced neurologic impairment, autophagy, and inflammation, which was significantly reversed by inhibition of miR-27a-3p or Dram2 overexpression. Mechanistically, northern blot and luciferase reporter assays indicated that circLrp1b up-regulated Dram2 expression by functioning as a sponge for miR-27a-3p to promote autophagy involved in TBI, which was reversed by DEX treatment. Collectively, this study demonstrated that DEX inhibits inflammatory response and autophagy involved in TBI in vivo through inactivation of the circLrp1b/miR-27a-3p/Dram2 signaling pathway.

The World Federation of Neurosurgical Societies Young Neurosurgeons Survey (Part II): Barriers to Professional Development and Service Delivery in Neurosurgery

BACKGROUND

Strengthening health systems requires attention to workforce, training needs, and barriers to service delivery. The World Federation of Neurosurgical Societies Young Neurosurgeons Committee survey sought to identify challenges for residents, fellows, and consultants within 10 years of training.

METHODS

An online survey was distributed to various neurosurgical societies, personal contacts, and social media platforms (April-November 2018). Responses were grouped by World Bank income classification into high-income countries (HICs), upper middle-income countries (UMICs), low-middle-income countries (LMICs), and low-income countries (LICs). Descriptive statistical analysis was performed.

RESULTS

In total, 953 individuals completed the survey. For service delivery, the limited number of trained neurosurgeons was seen as a barrier for 12.5%, 29.8%, 69.2%, and 23.9% of respondents from HICs, UMICs, LMICs, and LICs, respectively (P < 0.0001). The most reported personal challenge was the lack of opportunities for research (HICs, 34.6%; UMICs, 57.5%; LMICs, 61.6%; and LICs, 61.5%; P = 0.03). Other differences by income class included limited access to advice from experienced/senior colleagues (P < 0.001), neurosurgical journals (P < 0.0001), and textbooks (P = 0.02). Assessing how the World Federation of Neurosurgical Societies could best help young neurosurgeons, the most frequent requests (n = 953; 1673 requests) were research (n = 384), education (n = 296), and subspecialty/fellowship training (n = 232). Skills courses and access to cadaver dissection laboratories were also heavily requested.

CONCLUSIONS

Young neurosurgeons perceived that additional neurosurgeons are needed globally, especially in LICs and LMICs, and primarily requested additional resources for research and subspecialty training.

The predictive value of RDW in AKI and mortality in patients with traumatic brain injury

Background

Red blood cell distribution width (RDW) has been validated valuable in predicting outcome and acute kidney injury (AKI) in several clinical settings. The aim of this study was to explore whether RDW is associated with outcome and AKI in patients with traumatic brain injury (TBI).

Methods

Patients admitted to our hospital for TBI from January 2015 to August 2018 were included in this study. Multivariate logistic regression analysis was performed to identify risk factors of AKI and outcome in patients with TBI. The value of RDW in predicting AKI and outcome was evaluated by receiver operating characteristic (ROC) curve.

Results

Three hundred and eighteen patients were included in this study. The median of RDW was 14.25%. We divided subjects into two groups based on the median and compared difference of variables between two groups. The incidence of AKI and mortality was higher in high RDW (RDW > 14.25) group (31.45% vs 9.43%, P < .001; 69.81% vs 29.56%, P < .001). Spearman's method showed RDW was moderately associated with 90‐day Glasgow Outcome Scale (GOS) (P < .001). In multivariate logistic regression analysis, RDW, lymphocyte, chlorine, and serum creatinine were risk factors of AKI. And Glasgow Coma Scale (GCS), glucose, chlorine, AKI, and RDW were risk factors of mortality. The area under the ROC curve (AUC) of RDW for predicting AKI and mortality was 0.724 (0.662‐0.786) and 0.754 (0.701‐0.807), respectively. Patients with higher RDW were likely to have shorter median survival time (58 vs 70, P < .001).

Conclusions

Red blood cell distribution width is an independent risk factor of AKI and mortality in patients with TBI.

Neurosurgeons' experiences of conducting and disseminating clinical research in low- and middle-income countries: a qualitative study protocol

INTRODUCTION

Low-income and middle-income countries (LMICs) face the greatest burden of neurotrauma. However, most of the research published in scientific journals originates from high-income countries, suggesting those in LMICs are either not engaging in research or are not publishing it. Evidence originating in high-income countries may not be generalisable to LMICs; therefore, it is important to nurture research capacity in LMICs so that a relevant evidence base can be developed. However, little is published about specific challenges or contextual issues relevant to increasing research activity of neurosurgeons in LMICs. Therefore, the aim of this study was to understand neurosurgeons' experiences of, aspirations for and ability to conduct and disseminate clinical research in LMICs.

METHODS AND ANALYSIS

This is a pragmatic qualitative study situated within the naturalistic paradigm using focus groups and interviews with a purposive sample of neurosurgeons from LMICs. First, we will conduct asynchronous online focus groups with 36 neurosurgeons to broadly explore issues relevant to the study aim. Second, we will select 20 participants for follow-up semistructured interviews to explore concepts in more depth and detail than could be achieved in the focus group. Interviews will be audio-recorded and transcribed verbatim. A thematic analysis will be conducted following Braun and Clarke's six stages and will be supported by NVIVO software.

ETHICS AND DISSEMINATION

The University of Cambridge Psychology Research Ethics Committee reviewed this study and provided a favourable opinion in January 2020 (REF PRE.2020.006). Participants will provide informed consent, be able to withdraw at any time and will have their contributions kept confidential. The findings of the study will be shared with relevant stakeholders and disseminated in conference presentations and journal publications.

A Scoping Review of Registered Clinical Studies on Mild Traumatic Brain Injury and Concussion (2000 to 2019)

BACKGROUND

While many patients with mild traumatic brain injury (mTBI) or concussion recover completely, prolonged postconcussion symptoms remain a challenge for patients and an opportunity for clinical research. This has led to numerous research initiatives over the last 2 decades.

OBJECTIVE

To review the characteristics of clinical studies on management of mTBI/concussion; and to examine their definitions of mTBI/concussion.

METHODS

This scoping review included all clinical studies on diagnosis and management of patients with mTBI/concussion registered at www.clinicaltrials.gov from 2000 to June/2019. The terms “mild TBI/concussion” were used for the primary search. Definitions of mTBI/concussion were obtained from the protocols. When a definition was missing in the website, the study's investigators were contacted for clarification.

RESULTS

There were 225 interventional and 95 observational studies. Most of the studies are focused on treatment (54.7%) or diagnosis (37.5%), while 3.4% examined preventive measures, 2.8% evaluated prognostic instruments, and 1.6% developed registries. Most of the studies in this American database were single-center initiatives led by American and Canadian institutions. The definitions of mTBI/concussion differed widely among 109 studies.

CONCLUSION

The results of this review suggest that most of the clinical studies are focused on diagnosis and non-pharmacological therapies for patients with mTBI/concussion. The large number of differing definitions of mTBI/concussion among the studies creates significant limitations when comparing studies. The requirements for registering research protocols on mTBI/concussion should include the necessity to state the definition being used. There is a need for consensus on a uniform definition of concussion.

Recommendations of the Colombian Consensus Committee for the Management of Traumatic Brain Injury in Prehospital, Emergency Department, Surgery, and Intensive Care (Beyond One Option for Treatment of Traumatic Brain Injury: A Stratified Protocol [BOOTStraP])

Background  Traumatic brain injury (TBI) is a global public health problem. In Colombia, it is estimated that 70% of deaths from violence and 90% of deaths from road traffic accidents are TBI related. In the year 2014, the Ministry of Health of Colombia funded the development of a clinical practice guideline (CPG) for the diagnosis and treatment of adult patients with severe TBI. A critical barrier to the widespread implementation was identified-that is, the lack of a specific protocol that spans various levels of resources and complexity across the four treatment phases. The objective of this article is to present the process and recommendations for the management of patients with TBI in various resource environments, across the treatment phases of prehospital care, emergency department (ED), surgery, and intensive care unit. Methods  Using the Delphi methodology, a consensus of 20 experts in emergency medicine, neurosurgery, prehospital care, and intensive care nationwide developed recommendations based on 13 questions for the management of patients with TBI in Colombia. Discussion  It is estimated that 80% of the global population live in developing economies where access to resources required for optimum treatment is limited. There is limitation for applications of CPGs recommendations in areas where there is low availability or absence of resources for integral care. Development of mixed methods consensus, including evidence review and expertise points of good clinical practices can fill gaps in application of CPGs. BOOTStraP (Beyond One Option for Treatment of Traumatic Brain Injury: A Stratified Protocol) is intended to be a practical handbook for care providers to use to treat TBI patients with whatever resources are available. Results  Stratification of recommendations for interventions according to the availability of the resources on different stages of integral care is a proposed method for filling gaps in actual evidence, to organize a better strategy for interventions in different real-life scenarios. We develop 10 algorithms of management for building TBI protocols based on expert consensus to articulate treatment options in prehospital care, EDs, neurological surgery, and intensive care, independent of the level of availability of resources for care.

Editorial for "Evaluating the Therapeutic Effect of Low-Intensity Transcranial Ultrasound on Traumatic Brain Injury With Diffusion Kurtosis Imaging"

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 4 J. Magn. Reson. Imaging 2020;52:532-533.

A Systematic Review of Neurosurgical Care in Low-Income Countries

OBJECTIVE

More than 5 billion individuals lack access to essential surgical care. Neurosurgical care is especially limited in low-income countries (LICs). Studies describing neurosurgical care in LICs are critical for understanding global disparities in access to neurosurgical procedures. To better understand these disparities, we conducted a systematic review of the literature identifying neurosurgical patients in LICs.

METHODS

MEDLINE (PubMed), Embase (embase.com), and Cochrane Library (Wiley) databases were systematically searched to retrieve studies describing neurosurgical care in LICs as defined by the World Bank Country and Lending Groups income classification. All databases were searched from their inception; no date or language limits were applied. All the articles were blindly reviewed by 2 individuals. Data from eligible studies were extracted and summarized.

RESULTS

Of the 4377 citations screened, 154 studies met inclusion criteria. The number of publications substantially increased over the study period, with 49% (n = 76) of studies published in the last 5 years. Twenty-six percent (n = 40) of studies had a first author, and 30% (n = 46) had a senior author, affiliated with a country different from the LIC of study. The most common neurosurgical diagnosis was traumatic brain injury (24%, n = 37), followed by hydrocephalus (26%, n = 40), and neoplastic intracranial mass (10%, n = 16). Of LICs, 43% (n = 15/35) had no published neurosurgical literature.

CONCLUSIONS

There is a significant deficit in the literature on neurosurgical care in LICs. Efforts must focus on supporting research initiatives in LICs to improve publication bias and understand disparities in access to neurosurgical care in the lowest-resource countries.

Acute Kahweol Treatment Attenuates Traumatic Brain Injury Neuroinflammation and Functional Deficits

Traumatic brain injury (TBI) affects millions worldwide with devastating long-term effects on health and cognition. Emerging data suggest that targeting the immune response may offer promising strategies to alleviate TBI outcomes; kahweol, an anti-inflammatory diterpene that remains in unfiltered coffee, has been shown to be beneficial in neuronal recovery. Here, we examined whether kahweol could alleviate brain trauma-induced injury in a mouse model of TBI and its underlying mechanisms. TBI was induced by controlled cortical impact (CCI) and various doses of kahweol were intraperitoneally administered following injury. Contusion volume, brain edema, neurobehavioral deficits, and protein expression and activity were evaluated in both short-term and long-term recovery. We found that kahweol treatments significantly reduced secondary brain injury and improved neurobehavioral outcomes in TBI mice. These changes were accompanied by the attenuation of proinflammatory cytokine secretion, decreased microglia/macrophage activation, and reduction of neutrophil and leukocyte infiltration. In addition, continuous kahweol treatment further improved short-term TBI outcomes compared to single-dosage. Collectively, our data showed that kahweol protects against TBI by reducing immune responses and may serve as a potential therapeutic intervention for TBI patients.

The Evolution of the Role of External Ventricular Drainage in Traumatic Brain Injury

External ventricular drains (EVDs) are commonly used in neurosurgery in different conditions but frequently in the management of traumatic brain injury (TBI) to monitor and/or control intracranial pressure (ICP) by diverting cerebrospinal fluid (CSF). Their clinical effectiveness, when used as a therapeutic ICP-lowering procedure in contemporary practice, remains unclear. No consensus has been reached regarding the drainage strategy and optimal timing of insertion. We review the literature on EVDs in the setting of TBI, discussing its clinical indications, surgical technique, complications, clinical outcomes, and economic considerations.