Subarachnoid Hemorrhage

Deep learning-based recognition and segmentation of intracranial aneurysms under small sample size

The manual identification and segmentation of intracranial aneurysms (IAs) involved in the 3D reconstruction procedure are labor-intensive and prone to human errors. To meet the demands for routine clinical management and large cohort studies of IAs, fast and accurate patient-specific IA reconstruction becomes a research Frontier. In this study, a deep-learning-based framework for IA identification and segmentation was developed, and the impacts of image pre-processing and convolutional neural network (CNN) architectures on the framework's performance were investigated. Three-dimensional (3D) segmentation-dedicated architectures, including 3D UNet, VNet, and 3D Res-UNet were evaluated. The dataset used in this study included 101 sets of anonymized cranial computed tomography angiography (CTA) images with 140 IA cases. After the labeling and image pre-processing, a training set and test set containing 112 and 28 IA lesions were used to train and evaluate the convolutional neural network mentioned above. The performances of three convolutional neural networks were compared in terms of training performance, segmentation performance, and segmentation efficiency using multiple quantitative metrics. All the convolutional neural networks showed a non-zero voxel-wise recall (V-Recall) at the case level. Among them, 3D UNet exhibited a better overall segmentation performance under the relatively small sample size. The automatic segmentation results based on 3D UNet reached an average V-Recall of 0.797 ± 0.140 (3.5% and 17.3% higher than that of VNet and 3D Res-UNet), as well as an average dice similarity coefficient (DSC) of 0.818 ± 0.100, which was 4.1%, and 11.7% higher than VNet and 3D Res-UNet. Moreover, the average Hausdorff distance (HD) of the 3D UNet was 3.323 ± 3.212 voxels, which was 8.3% and 17.3% lower than that of VNet and 3D Res-UNet. The three-dimensional deviation analysis results also showed that the segmentations of 3D UNet had the smallest deviation with a max distance of +1.4760/-2.3854 mm, an average distance of 0.3480 mm, a standard deviation (STD) of 0.5978 mm, a root mean square (RMS) of 0.7269 mm. In addition, the average segmentation time (AST) of the 3D UNet was 0.053s, equal to that of 3D Res-UNet and 8.62% shorter than VNet. The results from this study suggested that the proposed deep learning framework integrated with 3D UNet can provide fast and accurate IA identification and segmentation.

Endothelial cell malfunction in unruptured intracranial aneurysm lesions revealed using a 3D-casted mold

Intracranial aneurysms (IA) are major causes of devastating subarachnoid hemorrhages. They are characterized by a chronic inflammatory process in the intracranial arterial walls triggered and modified by hemodynamic force loading. Because IA lesion morphology is complex, the blood flow conditions loaded on endothelial cells in each portion of the lesion in situ vary greatly. We created a 3D-casted mold of the human unruptured IA lesion and cultured endothelial cells on this model; it was then perfused with culture media to model physiological flow conditions. Gene expression profiles of endothelial cells in each part of the IA lesion were then analyzed. Comprehensive gene expression profile analysis revealed similar gene expression patterns in endothelial cells from each part of the IA lesion but gene ontology analysis revealed endothelial cell malfunction within the IA lesion. Histopathological examination, electron microscopy, and immunohistochemical analysis indicated that endothelial cells within IA lesions are damaged and dysfunctional. Thus, our findings reveal endothelial cell malfunction in IA lesions and provided new insights into IA pathogenesis.

Molecular mechanisms of neuronal death in brain injury after subarachnoid hemorrhage

Subarachnoid haemorrhage (SAH) is a common cerebrovascular disease with high disability and mortality rates worldwide. The pathophysiological mechanisms involved in an aneurysm rupture in SAH are complex and can be divided into early brain injury and delayed brain injury. The initial mechanical insult results in brain tissue and vascular disruption with hemorrhages and neuronal necrosis. Following this, the secondary injury results in diffused cerebral damage in the peri-core area. However, the molecular mechanisms of neuronal death following an aneurysmal SAH are complex and currently unclear. Furthermore, multiple cell death pathways are stimulated during the pathogenesis of brain damage. Notably, particular attention should be devoted to necrosis, apoptosis, autophagy, necroptosis, pyroptosis and ferroptosis. Thus, this review discussed the mechanism of neuronal death and its influence on brain injury after SAH.

Endovascular coiling versus microsurgical clipping for ruptured intracranial aneurysms: a meta-analysis and systematic review

Background

The purpose of this analysis is to evaluate the current evidence with regard to the effectiveness and safety between coiling and clipping in patients with ruptured intracranial aneurysms (RIAs).

Methods

We performed a meta-analysis that compared clipping with coiling between July 2000 and September 2021. PubMed, EMBASE, and the Cochrane Library were searched for related articles systematically. And the treatment efficacy and postoperative complications were analyzed.

Results

We identified three randomized controlled trials and thirty-seven observational studies involving 60,875 patients with ruptured cerebral aneurysms. The summary results showed that coiling was related a better quality of life (mRS0-2; OR=1.327; CI=1.093–1.612; p<0.05), a higher risk of mortality (OR=1.116; CI=1.054–1.180; p<0.05), higher rate of rebleeding (RR=1.410; CI=1.092–1.822; p<0.05), lower incidence of vasospasm (OR=0.787; CI=0.649–0.954; p<0.05), higher risk of hydrocephalous (RR=1.143; CI=1.043–1.252; p<0.05), lower risk of cerebral infarction (RR=0.669; CI=0.596–0.751; p<0.05), lower risk of neuro deficits (RR=0.720; CI=0.582-0.892; p<0.05), and a lower rate of complete occlusion (OR=0.495; CI=0.280-0.876; p<0.05).

Conclusion

Coiling was significantly associated with a better life quality (mRS0-2), a lower incidence of postoperative complications, and a higher rate of mortality, rebleeding, hydrocephalous, and a lower rate of complete occlusion than clipping.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41016-022-00283-3.

Microsurgery versus embolization: different risk factors for short- and longterm outcomes of patients with ruptured aneurysms

PURPOSE

To evaluate the risk factors for poor outcomes after surgical and endovascular treatment of aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

Patients with ≥ 18-years of age and aSAH were included, while patients who died within 12 h of admission or lost follow-up were excluded. All participants underwent standardized clinical and radiological assessment on admission and were reassessed at discharge and at 6-months follow-up using the Glasgow Outcome Scale (GOS).

RESULTS

Death at discharge was associated with female gender, anterior communication artery (ACoA) aneurysm location and presence of atherosclerotic plaque in the surgical group, and with age in the endovascular group. Both groups had clinical condition on follow-up associated with mFisher score on admission and hypertension. GOS on follow-up was also associated with presence of atherosclerotic plaque and multiple aneurysms in surgical group, and with age in endovascular group.

CONCLUSIONS

Subjects treated surgically are prone to unfavorable outcomes if atherosclerotic plaques and multiple aneurysms are present. In patients with endovascular treatment, age was the main predictor of clinical outcome.

Endothelial NOX4 aggravates eNOS uncoupling by decreasing dihydrofolate reductase after subarachnoid hemorrhage

Endothelial malfunction is a major contributor to early or delayed vasospasm after subarachnoid hemorrhage (SAH). As a representative form of endothelial dysfunction, endothelial nitric oxide synthase (eNOS) uncoupling leads to a reduction in nitric oxide (NO) generated by endothelial cells. In this study, we investigated how the interaction between endothelial NOX4 (nicotinamide adenine dinucleotide phosphate oxidase 4) and DHFR (dihydrofolate reductase) contributes to eNOS uncoupling after SAH. Setanaxib and the adeno-associated virus (AAV) targeting brain vascular endothelia were injected through the tail vein and the expression and localization of proteins were examined by western blot and immunofluorescence staining. The NO content was measured using the NO assay kit, and laser speckle contrast imaging was used to assess cortical perfusion. ROS (reactive oxygen species) level was detected by DHE (dihydroethidium) staining, DCFH-DA (2',7'-dichlorofluorescin diacetate) staining and H₂O₂ (hydrogen peroxide) measurement. The Garcia score was employed to examine neurological function. Setanaxib is widely used for its preferential inhibition for NOX1/4 over other NOX isoforms. After endothelial NOX4 was inhibited by Setanaxib in a mouse model of SAH, the endothelial DHFR level was significantly elevated, which attenuated eNOS uncoupling, increased cortical perfusion, and improved the neurological function. The protective role of inhibiting endothelial NOX4, however, disappeared after knocking down endothelial DHFR. Our results suggest that endothelial DHFR decreased significantly because of the elevated level of endothelial NOX4, which aggravated eNOS uncoupling after SAH, leading to decreased cortical perfusion and worse neurological outcome.

Exosomes in subarachnoid hemorrhage: A scoping review

INTRODUCTION

Vasospasm is a common complication following subarachnoid hemorrhage (SAH), causing increased ischemia and tissue injury, and is implicated as a major risk factor for poor outcomes. The success of current treatments for vasospasm is limited, with limited efficacy and unclear clinical benefits. Exosomes, vesicles that carry small molecules such as miRNA, have been theorized as a potential vasospasm treatment. In this study, we aim to survey the current literature discussing the role of exosomes in the setting of SAH.

METHODS

Following PRISMA guidelines, we performed a scoping review evaluating the role of exosomes in the treatment of SAH. The search was conducted using PubMed and Scopus, and all original research papers studying exosomal profiles of SAH research subjects or SAH therapy were eligible for inclusion.

RESULTS

After screening and full text review, seven papers were selected for final inclusion. Of these, two studies analyzed the expression profile of endogenous exosomes after SAH. Four papers identified and characterized miRNA-based exosomal therapies to attenuate early brain injury (EBI) after SAH. One paper discussed the role of protein overexpression in exosome delivery of miRNA for EBI after SAH. Interestingly, all identified papers studying exosomal therapy demonstrated anti-apoptotic or anti-inflammatory effects of miRNA exosomes acting via the BDNF/TrkB/CREB or HDAC3/NF-κB pathways.

CONCLUSION

Identified studies demonstrate potential neuroprotective benefits of miRNA-based exosomal treatment of EBI and SAH. Findings warrant further research investigating the anti-inflammatory and anti-apoptotic role of exosomal miRNA delivery in SAH models, specifically targeting the common pathway identified by the authors.

Spontaneous Subarachnoid Haemorrhage After COVID-19 Vaccination; a Rare Case Report

Introduction: Cerebrovascular incidents are considered uncommon but important complications of vaccination against coronavirus disease-2019 (COVID-19). Subarachnoid hemorrhages (SAH) usually occur due to an underlying cerebral aneurysm. In this study, we have reported a subarachnoid hemorrhage incidence in a patient shortly after receiving the COVID-19 vaccine (ChAdOx1-AstraZeneca). Case Presentation: The patient was a 69-year-old male with no remarkable risk factors, referred to the emergency room with complaints of headache, nausea, and vomiting. The patient had received his first dose of vaccine against COVID-19 four days before symptoms started. An aggravated headache, nausea, elevated blood pressure (180/100), and drowsiness occurred on the second day of admission. Imaging from head computed tomographic (CT) scans implied acute hydrocephalus and increased intracranial pressure (ICP) caused by subarachnoid hemorrhage. The condition was treated by inserting an external ventricular drain (EVD), removed after one week, and the patient was discharged with no permanent deficit. We found no underlying vascular abnormality in primary and follow-up cerebral angiographies. Conclusions: There are reports of cerebral hemorrhages caused by COVID-19 vaccination, mostly intra-parenchymal. Our study observed a type of cerebrovascular event that has not been reported frequently. Vaccine-associated cerebrovascular events, however rarely, are critical. It is important to demonstrate possible risks and complications, as vaccination programs against COVID-19 have become an essential part of health care in most countries.

Association between serum sodium and in-hospital mortality among critically ill patients with spontaneous subarachnoid hemorrhage

Objective

The aim of this study was to retrospectively explore the relationship between serum sodium and in-hospital mortality and related factors in critically ill patients with spontaneous subarachnoid hemorrhage (SAH).

Methods

Data were collected from the Medical Information Mart for Intensive Care IV database. Restricted cubic splines were used to explore the relationship between serum sodium and in-hospital mortality. Receiver operating characteristic analysis was used to calculate the optimal cutoff value of sodium fluctuation, and decision curve analysis was plotted to show the net benefit of different models containing serum sodium.

Results

A total of 295 patients with spontaneous SAH were included in the retrospective analysis. The level of sodium on ICU admission and minimum sodium in the ICU had a statistically significant non-linear relationship with in-hospital mortality (non-linear P-value < 0.05, total P-value < 0.001). Serum sodium on ICU admission, minimum serum sodium during ICU, and sodium fluctuation were independently associated with in-hospital mortality with odds ratios being 1.23 (95% confidence interval (CI): 1.04-1.45, P = 0.013), 1.35 (95% CI: 1.18-1.55, P < 0.001), and 1.07 (95% CI: 1.00-1.14, P = 0.047), respectively. The optimal cutoff point was 8.5 mmol/L to identify in-hospital death of patients with spontaneous SAH with sodium fluctuation, with an AUC of 0.659 (95% CI 0.573-0.744).

Conclusion

Among patients with spontaneous SAH, we found a J-shaped association between serum sodium on ICU admission and minimum sodium values during ICU with in-hospital mortality. Sodium fluctuation above 8.5 mmol/L was independently associated with in-hospital mortality. These results require being tested in prospective trials.

Self-supervised learning enables 3D digital subtraction angiography reconstruction from ultra-sparse 2D projection views: A multicenter study

3D digital subtraction angiography (DSA) reconstruction from rotational 2D projection X-ray angiography is an important basis for diagnosis and treatment of intracranial aneurysms (IAs). The gold standard requires approximately 133 different projection views for 3D reconstruction. A method to significantly reduce the radiation dosage while ensuring the reconstruction quality is yet to be developed. We propose a self-supervised learning method to realize 3D-DSA reconstruction using ultra-sparse 2D projections. 202 cases (100 from one hospital for training and testing, 102 from two other hospitals for external validation) suspected to be suffering from IAs were conducted to analyze the reconstructed images. Two radiologists scored the reconstructed images from internal and external datasets using eight projections and identified all 82 lesions with high diagnostic confidence. The radiation dosages are approximately 1/16.7 compared with the gold standard method. Our proposed method can help develop a revolutionary 3D-DSA reconstruction method for use in clinic.

Lactate-to-albumin ratio is associated with in-hospital mortality in patients with spontaneous subarachnoid hemorrhage and a nomogram model construction

Introduction

Subarachnoid hemorrhage (SAH) is a severe hemorrhagic stroke with high mortality. However, there is a lack of clinical tools for predicting in-hospital mortality in clinical practice. LAR is a novel clinical marker that has demonstrated prognostic significance in a variety of diseases.

Methods

Critically ill patients diagnosed and SAH with their data in the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database and the eICU Collaborative Research Database (eICU-CRD) were included in our study. Multivariate logistic regression was utilized to establish the nomogram.

Results

A total of 244 patients with spontaneous SAH in the MIMIC-IV database were eligible for the study as a training set, and 83 patients in eICU-CRD were included for external validation. Data on clinical characteristics, laboratory parameters and outcomes were collected. Univariate and multivariate logistic regression analysis identified age (OR: 1.042, P-value: 0.003), LAR (OR: 2.592, P-value: 0.011), anion gap (OR: 1.134, P-value: 0.036) and APSIII (OR: 1.028, P-value: < 0.001) as independent predictors of in-hospital mortality and we developed a nomogram model based on these factors. The nomogram model incorporated with LAR, APSIII, age and anion gap demonstrated great discrimination and clinical utility both in the training set (accuracy: 77.5%, AUC: 0.811) and validation set (accuracy: 75.9%, AUC: 0.822).

Conclusion

LAR is closely associated with increased in-hospital mortality of patients with spontaneous SAH, which could serve as a novel clinical marker. The nomogram model combined with LAR, APSIII, age, and anion gap presents good predictive performance and clinical practicability.

Multinational Genome-Wide Association Study and Functional Genomics Analysis Implicates Decreased SIRT3 Expression Underlying Intracranial Aneurysm Risk

BACKGROUND

The genetic mechanisms regulating intracranial aneurysm (IA) formation and rupture are largely unknown. To identify germline-genetic risk factors for IA, we perform a multinational genome-wide association study (GWAS) of individuals from the United Kingdom, Finland, and Japan.

OBJECTIVE

To identify a shared, multinational genetic basis of IA.

METHODS

Using GWAS summary statistics from UK Biobank, FinnGen, and Biobank Japan, we perform a meta-analysis of IA, containing ruptured and unruptured IA cases. Logistic regression was used to identify IA-associated single-nucleotide polymorphisms. Effect size was calculated using the coefficient r , estimating the contribution of the single-nucleotide polymorphism to the genetic variance of the trait. Genome-wide significance was set at 5.0 × 10 -8 . Expression quantitative trait loci mapping and functional genomics approaches were used to infer mechanistic consequences of implicated variants.

RESULTS

Our cohort contained 155 154 individuals (3132 IA cases and 152 022 controls). We identified 4 genetic loci reaching genome-wide: rs73392700 ( SIRT3 , effect size = 0.28, P = 4.3 × 10 -12 ), rs58721068 ( EDNRA , effect size = -0.20, P = 4.8 × 10 -12 ), rs4977574 ( AL359922.1 , effect size = 0.18, P = 7.9 × 10 -12 ), and rs11105337 ( ATP2B1 , effect size = -0.15, P = 3.4 × 10 -8 ). Expression quantitative trait loci mapping suggests that rs73392700 has a large effect size on SIRT3 gene expression in arterial and muscle, but not neurological, tissues. Functional genomics analysis suggests that rs73392700 causes decreased SIRT3 gene expression.

CONCLUSION

We perform a multinational GWAS of IA and identify 4 genetic risk loci, including 2 novel IA risk loci ( SIRT3 and AL359922.1 ). Identification of high-risk genetic loci across ancestries will enable population-genetic screening approaches to identify patients with IA.

Lumbar Drainage After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

OBJECTIVE

This study reviews the use of lumbar drains (LDs) after aneurysmal subarachnoid hemorrhage (aSAH) and compares the outcomes to those associated with external ventricular drains (EVDs) and controls.

METHODS

A comprehensive search of the literature was performed. English language studies with a sample size of more than 10 patients were included. One-arm and 2-arm meta-analyses were designed to compare external drainage groups. Random-effects models, heterogeneity measures, and risk of bias were calculated.

RESULTS

Seventeen studies were included in the meta-analysis. The 2-arm meta-analysis comparing the LD to no drainage after aSAH found a significant improvement in the postoperative modified Rankin Scale (mRS) score (0-2) within 1 month of hospital discharge in the LD group (P = 0.003), a lower mortality rate (P = 0.03), fewer cases of clinical vasospasm (P = 0.007), and a lower incidence of ischemic stroke or delayed ischemic neurological deficits (P = 0.003). When the LD was compared to EVDs, a significant improvement in the postoperative mRS score (0-2) within 1 month of discharge was found in the LD group (P < 0.001). In the LD group, rebleeding occurred in 15 (3.4%) cases and meningitis occurred in 50 (4.7%) cases.

CONCLUSIONS

Compared with patients without cerebrospinal fluid drainage, patients with the LD after aSAH had lower mortality rates, lower risk of clinical vasospasm, and lower risk of ischemic stroke, and they were more likely to have an mRS score of 0-2 within 1 month of discharge. Compared with patients with EVDs, patients with the LD were more likely to have an mRS score of 0-2 within 1 month of discharge.

Hemorrhagic Cerebral Insults and Secondary Takotsubo Syndrome: Findings in a Novel In Vitro Model Using Human Blood Samples

Intracranial hemorrhage results in devastating forms of cerebral damage. Frequently, these results also present with cardiac dysfunction ranging from ECG changes to Takotsubo syndrome (TTS). This suggests that intracranial bleeding due to subarachnoid hemorrhage (SAH) disrupts the neuro-cardiac axis leading to neurogenic stress cardiomyopathy (NSC) of different degrees. Following this notion, SAH and secondary TTS could be directly linked, thus contributing to poor outcomes. We set out to test if blood circulation is the driver of the brain-heart axis by investigating serum samples of TTS patients. We present a novel in vitro model combining SAH and secondary TTS to mimic the effects of blood or serum, respectively, on blood-brain barrier (BBB) integrity using in vitro monolayers of an established murine model. We consistently demonstrated decreased monolayer integrity and confirmed reduced Claudin-5 and Occludin levels by RT-qPCR and Western blot and morphological reorganization of actin filaments in endothelial cells. Both tight junction proteins show a time-dependent reduction. Our findings highlight a faster and more prominent disintegration of BBB in the presence of TTS and support the importance of the bloodstream as a causal link between intracerebral bleeding and cardiac dysfunction. This may represent potential targets for future therapeutic inventions in SAH and TTS.

Does the COVID-19 Screening Test Affect the Postoperative Prognosis of Patients Who Undergo Emergency Surgery for Cerebral Hemorrhage?

Objective

The coronavirus disease 2019 (COVID-19) pandemic has affected all medical fields, including neurosurgery. Particularly, performing preoperative screening tests has become mandatory, potentially extending the time from admission to the emergency room and operating room, thus possibly affecting patients' prognosis. This study aimed to determine the influence of COVID-19 screening time on patients' postoperative prognosis.

Methods

From September 10, 2020, to May 31, 2021, we retrospectively evaluated 54 patients with cerebral hemorrhage who underwent emergency surgery in the emergency room after the screening test. The control group included 89 patients with cerebral hemorrhage who underwent emergency surgery between January 2019 and March 2020, i.e., the period before the COVID-19 pandemic. Prognosis was measured using the Glasgow Coma Scale scores, which were obtained preoperatively, postoperatively, and at discharge, and the modified Rankin Scale (mRS). Additionally, unfavorable outcomes (mRS score 3-6) and in-hospital mortality rates were investigated for postoperative prognostic assessments.

Results

No remarkable differences were observed in the time to surgical intervention and prognostic evaluation scores between patients with cerebral hemorrhage who underwent COVID-19 screening tests and subjects in the control group.

Conclusion

This study confirmed that patient treatment and prognosis were not significantly affected by additional preoperative screening testing times during the pandemic. We believe that our results are informative for the evaluation and performance of emergency neurosurgery during the pandemic.

Dexras1 Induces Dysdifferentiation of Oligodendrocytes and Myelin Injury by Inhibiting the cAMP-CREB Pathway after Subarachnoid Hemorrhage

White matter damage (WMD), one of the research hotspots of subarachnoid hemorrhage (SAH), mainly manifests itself as myelin injury and oligodendrocyte differentiation disorder after SAH, although the specific mechanism remains unclear. Dexamethasone-induced Ras-related protein 1(Dexras1) has been reported to be involved in nervous system damage in autoimmune encephalitis and multiple sclerosis. However, whether Dexras1 participates in dysdifferentiation of oligodendrocytes and myelin injury after SAH has yet to be examined, which is the reason for creating the research content of this article. Here, intracerebroventricular lentiviral administration was used to modulate Dexras1 levels in order to determine its functional influence on neurological injury after SAH. Immunofluorescence, transmission electron microscopy, and Western blotting methods, were used to investigate the effects of Dexras1 on demyelination, glial cell activation, and differentiation of oligodendrocyte progenitor cells (OPCs) after SAH. Primary rat brain neurons were treated with oxyhemoglobin to verify the association between Dexras1 and cAMP-CREB. The results showed that Dexras1 levels were significantly increased upon in vivo SAH model, accompanied by OPC differentiation disturbances and myelin injury. Dexras1 overexpression significantly worsened OPC dysdifferentiation and myelin injury after SAH. In contrast, Dexras1 knockdown ameliorated myelin injury, OPC dysdifferentiation, and glial cell activation. Further research of the underlying mechanism discovered that the cAMP-CREB pathway was inhibited after Dexras1 overexpression in the in vitro model of SAH. This study is the first to confirm that Dexras1 induced oligodendrocyte dysdifferentiation and myelin injury after SAH by inhibiting the cAMP-CREB pathway. This present research may reveal novel therapeutic targets for the amelioration of brain injury and neurological dysfunction after SAH.

Safety of early rehabilitation in patients with aneurysmal subarachnoid hemorrhage: A retrospective cohort study

OBJECTIVE

To investigate the safety and efficacy of early rehabilitation in patients with aneurysmal subarachnoid hemorrhage (aSAH) patients.

METHODS

One hundred eleven patients with aSAH admitted between April 2015 and March 2019, were retrospectively evaluated. The early rehabilitation program was introduced in April 2017 to actively promote mobilization and walking training for aSAH patients. Therefore, patients were divided into two groups (The conventional group (n = 55) and the early rehabilitation group (n == 56). Clinical characteristics, mobilization progression, and treatment variables were analyzed. Complications (rebleeding, symptomatic cerebral vasospasm, hydrocephalus, disuse complications,) and a modified Rankin Scale (mRS) at 90 days were compared in two groups. Factors associated with favorable outcomes (mRS≤2) at 90 days were also assessed.

RESULTS

The early rehabilitation group had a significantly shorter span to first walking (9 vs. 5 days; P = 0.007). The prevalence of complications was not significantly increased in the early rehabilitation group. Approximately 40% of patients in both groups had pneumonia and urinary tract infections but significantly reduced antibiotic-administration days (13 vs. 6 days; P < 0.001). mRS at 90 days also showed significant improvement in the early rehabilitation group (3 vs. 2; P=0.01). Multivariate logistic regression analysis of favorable outcomes associated that the administration of the early rehabilitation program has a significant independent factor (odds ratio, 3.03; 95% confidence interval, 1.1-8.37).

CONCLUSIONS

Early rehabilitation for patients with aSAH can be feasible without increasing complication occurrences. The early rehabilitation program with active mobilization and walking training reduced antibiotic use and was associated with improved independence.

Janus Faced HMGB1 and Post-Aneurysmal Subarachnoid Hemorrhage (aSAH) Inflammation

Aneurysmal subarachnoid hemorrhage (aSAH), resulting majorly from the rupture of intracranial aneurysms, is a potentially devastating disease with high morbidity and mortality. The bleeding aneurysms can be successfully secured; however, the toxic and mechanical impact of the blood extravasation into the subarachnoid space damages the brain cells leading to the release of different damage-associated molecular pattern molecules (DAMPs). DAMPs upregulate the inflammation after binding their cognate receptors on the immune cells and underlies the early and delayed brain injury after aSAH. Moreover, these molecules are also associated with different post-aSAH complications, which lead to poor clinical outcomes. Among these DAMPs, HMGB1 represents a prototypical protein DAMP that has been well characterized for its proinflammatory role after aSAH and during different post-aSAH complications. However, recent investigations have uncovered yet another face of HMGB1, which is involved in the promotion of brain tissue remodeling, neurovascular repair, and anti-inflammatory effects after SAH. These different faces rely on different redox states of HMGB1 over the course of time after SAH. Elucidation of the dynamics of these redox states of HMGB1 has high biomarker as well as therapeutic potential. This review mainly highlights these recent findings along with the conventionally described normal role of HMGB1 as a nuclear protein and as a proinflammatory molecule during disease (aSAH).

Exosome-Encapsulated microRNA-140-5p Alleviates Neuronal Injury Following Subarachnoid Hemorrhage by Regulating IGFBP5-Mediated PI3K/AKT Signaling Pathway

Recent literature has highlighted the therapeutic implication of exosomes (Exos) released by adipose tissue-originated stromal cells (ADSCs) in regenerative medicine. Herein, the current study sought to examine the potential protective effects of ADSC-Exos on neuronal injury following subarachnoid hemorrhage (SAH) by delivering miR-140-5p. Firstly, isolated primary neurons were co-cultured together with well-identified ADSC-Exos. TDP-43-treated neurons were subsequently treated with PKH67-ADSC-Exos and Cy3-miR-140-5p to assess whether ADSC-Exos could transmit miR-140-5p to the recipient neurons to affect their behaviors. Moreover, a luciferase assay was carried out to identify the presumable binding of miR-140-5p to IGFBP5. IGFBP5 rescue experimentation was also performed to testify whether IGFBP5 conferred the impact of miR-140-5p on neuronal damage. The role of PI3K/AKT signaling pathway was further analyzed with the application of its inhibitor miltefosine. Lastly, SAH rat models were developed for in vivo validation. It was found that ADSC-Exos conferred protection against TDP-43-caused neuronal injury by augmenting viability and suppressing cell apoptosis. In addition, miR-140-5p was transmitted from ADSC-Exos to neurons and post-transcriptionally downregulated the expression of IGFBP5. As a result, by means of suppressing IGFBP5 and activating the PI3K/AKT signaling pathway, miR-140-5p from ADSC-Exos induced a neuroprotective effect. Furthermore, in vivo findings substantiated the aforementioned protective role of ADSC-Exos-miR-140-5p, contributing to protection against SAH-caused neurological dysfunction. Collectively, our findings indicated that ADSC-Exos-miR-140-5p could inhibit TDP-43-induced neuronal injury and attenuate neurological dysfunction of SAH rats by inhibiting IGFBP5 and activating the PI3K/Akt signaling pathway.

Admission Serum Iron as an Independent Risk Factor for Postoperative Delayed Cerebral Ischemia Following Aneurysmal Subarachnoid Hemorrhage: A Propensity-Matched Analysis

This study aimed to investigate the association between serum iron (SI) and postoperative delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH). We retrospectively analyzed 985 consecutive adult patients diagnosed with aSAH. Demographic, clinical, and laboratory data were recorded. Univariate and multivariate analyses were employed to assess the association between SI and DCI. Propensity-score matching (PSM) analysis was implemented to reduce confounding. Postoperative DCI developed in 14.38% of patients. Lower SI upon admission was detected in aSAH patients with severe clinical conditions and severe aSAH. SI was negatively correlated with WFNS grade (r = −0.3744, p < 0.001) and modified Fisher (mFisher) grade (r = −0.2520, p < 0.001). Multivariable analysis revealed lower SI was independently associated with DCI [odds ratios (OR) 0.281, 95% confidence interval (CI) 0.177−0.448, p < 0.001], while WFNS grade and mFisher grade were not. The receiver-operating characteristics (ROC) curve analysis of SI for DCI gave an area under the curve (AUC) of 0.7 and an optimal cut-off of 7.5 μmol/L (95% CI 0.665 to 0.733, p < 0.0001). PSM demonstrated the DCI group had a significantly lower SI than the non-DCI group (10.91 ± 6.86 vs. 20.34 ± 8.01 μmol/L, p < 0.001). Lower SI remained a significant independent predictor for DCI and an independent poor prognostic factor of aSAH in multivariate analysis (OR 0.363, 95% CI 0.209−0.630, p < 0.001). The predictive performance of SI for poor outcome had a corresponding AUC of 0.718 after PSM. Lower SI upon admission is significantly associated with WFNS grade, mFisher grade, and predicts postoperative DCI and poor outcome at 90 days following aSAH.

Stability of unruptured intracranial aneurysms in the anterior circulation: nomogram models for risk assessment

OBJECTIVE

The probable stability of the lesion is critical in guiding treatment decisions in unruptured intracranial aneurysms (IAs). The authors aimed to develop multidimensional predictive models for the stability of unruptured IAs.

METHODS

Patients with unruptured IAs in the anterior circulation were prospectively enrolled and regularly followed up. Clinical data were collected, IA morphological features were assessed, and adjacent hemodynamic features were quantified with patient-specific computational fluid dynamics modeling. Based on multivariate logistic regression analyses, nomograms incorporating these factors were developed in a primary cohort (patients enrolled between January 2017 and February 2018) to predict aneurysm rupture or growth within 2 years. The predictive accuracies of the nomograms were compared with the population, hypertension, age, size, earlier rupture, and site (PHASES) and earlier subarachnoid hemorrhage, location, age, population, size, and shape (ELAPSS) scores and validated in the validation cohort (patients enrolled between March and October 2018).

RESULTS

Among 231 patients with 272 unruptured IAs in the primary cohort, hypertension, aneurysm location, irregular shape, size ratio, normalized wall shear stress average, and relative resident time were independently related to the 2-year stability of unruptured IAs. The nomogram including clinical, morphological, and hemodynamic features (C+M+H nomogram) had the highest predictive accuracy (c-statistic 0.94), followed by the nomogram including clinical and morphological features (C+M nomogram; c-statistic 0.89), PHASES score (c-statistic 0.68), and ELAPSS score (c-statistic 0.58). Similarly, the C+M+H nomogram had the highest predictive accuracy (c-statistic 0.94) in the validation cohort (85 patients with 97 unruptured IAs).

CONCLUSIONS

Hemodynamics have predictive values for 2-year stability of unruptured IAs treated conservatively. Multidimensional nomograms have significantly higher predictive accuracies than conventional risk prediction scores.

Intracranial Aneurysm Classifier Using Phenotypic Factors: An International Pooled Analysis

Intracranial aneurysms (IAs) are usually asymptomatic with a low risk of rupture, but consequences of aneurysmal subarachnoid hemorrhage (aSAH) are severe. Identifying IAs at risk of rupture has important clinical and socio-economic consequences. The goal of this study was to assess the effect of patient and IA characteristics on the likelihood of IA being diagnosed incidentally versus ruptured. Patients were recruited at 21 international centers. Seven phenotypic patient characteristics and three IA characteristics were recorded. The analyzed cohort included 7992 patients. Multivariate analysis demonstrated that: (1) IA location is the strongest factor associated with IA rupture status at diagnosis; (2) Risk factor awareness (hypertension, smoking) increases the likelihood of being diagnosed with unruptured IA; (3) Patients with ruptured IAs in high-risk locations tend to be older, and their IAs are smaller; (4) Smokers with ruptured IAs tend to be younger, and their IAs are larger; (5) Female patients with ruptured IAs tend to be older, and their IAs are smaller; (6) IA size and age at rupture correlate. The assessment of associations regarding patient and IA characteristics with IA rupture allows us to refine IA disease models and provide data to develop risk instruments for clinicians to support personalized decision-making.

Microsurgical Management of Posterior Circulation Aneurysms: A Retrospective Study on Epidemiology, Outcomes, and Surgical Approaches

Posterior circulation aneurysms have been regarded as the most challenging for endovascular coiling and microsurgical occlusion. The role of microsurgical treatment is gradually being overlooked and diminishing in the trend of endovascular treatment. As microsurgical occlusion of posterior circulation aneurysms is decreasing, we present our relevant experience to evaluate treatment options and surgical approaches. A retrospective study was conducted in the Department of Neurosurgery of the First Affiliated Hospital of Soochow University between 2016 and 2021. Patients with posterior circulation aneurysms treated by clipping, bypass, and trapping were enrolled and followed up for at least six months. We included 50 patients carrying 53 posterior circulation aneurysms, 43 of whom had aneurysm ruptures. The posterior cerebral artery and posterior inferior cerebellar artery were the most common aneurysm locations. Direct clipping was performed in 43 patients, while bypass and trapping was performed in six patients. The retrosigmoid, far-lateral, and midline or paramedian suboccipital approaches were performed for those aneurysms in the middle and lower thirds. Aneurysms in the upper third required the lateral supraorbital approach, pterional approach, subtemporal approach, and occipital craniotomy. The lateral supraorbital approach was utilized in seven patients for aneurysms above the posterior clinoid process. Thirty-four patients recovered well with modified Rankin score 0-3 at discharge. No patient experienced aneurysm recurrence during the mean follow-up period of 3.57 years. Microsurgery clipping and bypass should be considered in conjunction with endovascular treatment as a treatment option in posterior circulation aneurysms. The lateral supraorbital approach is a feasible, safe, and simple surgical approach for aneurysms above the posterior clinoid process.

Microsurgical Management of Posterior Circulation Aneurysms: A Retrospective Study on Epidemiology, Outcomes, and Surgical Approaches

Posterior circulation aneurysms have been regarded as the most challenging for endovascular coiling and microsurgical occlusion. The role of microsurgical treatment is gradually being overlooked and diminishing in the trend of endovascular treatment. As microsurgical occlusion of posterior circulation aneurysms is decreasing, we present our relevant experience to evaluate treatment options and surgical approaches. A retrospective study was conducted in the Department of Neurosurgery of the First Affiliated Hospital of Soochow University between 2016 and 2021. Patients with posterior circulation aneurysms treated by clipping, bypass, and trapping were enrolled and followed up for at least six months. We included 50 patients carrying 53 posterior circulation aneurysms, 43 of whom had aneurysm ruptures. The posterior cerebral artery and posterior inferior cerebellar artery were the most common aneurysm locations. Direct clipping was performed in 43 patients, while bypass and trapping was performed in six patients. The retrosigmoid, far-lateral, and midline or paramedian suboccipital approaches were performed for those aneurysms in the middle and lower thirds. Aneurysms in the upper third required the lateral supraorbital approach, pterional approach, subtemporal approach, and occipital craniotomy. The lateral supraorbital approach was utilized in seven patients for aneurysms above the posterior clinoid process. Thirty-four patients recovered well with modified Rankin score 0–3 at discharge. No patient experienced aneurysm recurrence during the mean follow-up period of 3.57 years. Microsurgery clipping and bypass should be considered in conjunction with endovascular treatment as a treatment option in posterior circulation aneurysms. The lateral supraorbital approach is a feasible, safe, and simple surgical approach for aneurysms above the posterior clinoid process.

microRNAs in Subarachnoid Hemorrhage (Review of Literature)

Recently, many studies have shown that microRNAs (miRNAs) in extracellular bioliquids are strongly associated with subarachnoid hemorrhage (SAH) and its complications. The article presents issues related to the occurrence of subarachnoid hemorrhage (epidemiology, symptoms, differential diagnosis, examination, and treatment of the patient) and a review of current research on the correlation between miRNAs and the complications of SAH. The potential use of miRNAs as biomarkers in the treatment of SAH is presented.

Burden of stroke in North Africa and Middle East, 1990 to 2019: a systematic analysis for the global burden of disease study 2019

BACKGROUND

While several studies investigated the epidemiology and burden of stroke in the North Africa and Middle East region, no study has comprehensively evaluated the age-standardized attributable burden to all stroke subtypes and their risk factors yet.

OBJECTIVE

The aim of the present study is to explore the regional distribution of the burden of stroke, including ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage, and the attributable burden to its risk factors in 2019 among the 21 countries of North Africa and Middle East super-region.

METHODS

The data of the Global Burden of Disease Study (GBD) 2019 on stroke incidence, prevalence, death, disability-adjusted life years (DALYs), years of life lost (YLLs), years lived with disability (YLDs) rates, and attributed deaths, DALYs, YLLs, and YLDs to stroke risk factors were used for the present study.

RESULTS

The age-standardized deaths, DALYs, and YLLs rates were diminished statistically significant by 27.8, 32.0, and 35.1% from 1990 to 2019, respectively. Attributed deaths, DALYs, and YLLs to stroke risk factors, including high systolic blood pressure, high body-mass index, and high fasting plasma glucose shrank statistically significant by 24.9, 25.8, and 28.8%, respectively.

CONCLUSION

While the age-standardized stroke burden has reduced during these 30 years, it is still a concerning issue due to its increased burden in all-age numbers. Well-developed primary prevention, timely diagnosis and management of the stroke and its risk factors might be appreciated for further decreasing the burden of stroke and its risk factors and reaching Sustainable Development Goal 3.4 target for reducing premature mortality from non-communicable diseases.

Longitudinal ventricular cerebrospinal fluid profile in patients with spontaneous subarachnoid hemorrhage

Background

Spontaneous subarachnoid hemorrhage (SAH) is a severe neurological disease that frequently requires placement of external ventricular drainage (EVD). Cerebrospinal fluid (CSF) obtained via the drain is used to detect potential complications of SAH.

Objective

This study aimed to describe the longitudinal profile of routine CSF parameters in patients with SAH and to identify associations with neurological complications.

Methods

A total of thirty-three patients with spontaneous SAH who required an EVD and had at least three consecutive CSF samples collected over a period of more than 7 days were included in this study.

Results

A median of 6 longitudinally collected CSF samples per patient were available within 1–22 days after SAH onset. Overall, red blood cells (RBC) steadily decreased over time, whereas white blood cells (WBC) and total protein (TP) increased until days 6 and 13, respectively, and decreased thereafter. The estimated decay rates of RBC, WBC, and TP were 28, 22, and 6% per day. Distinct CSF patterns over time were linked to known complications after SAH. Patients with rebleeding showed increased RBC, TP, and phagocytosing cells compared to patients without re-bleeding. For ventriculitis, an elevated cell index with a higher proportion of granulocytes was characteristic. CSF of patients with delayed cerebral ischemia showed increased RBC and WBC compared to patients without DCI. Early CSF WBC and cell index were predictive for the occurrence of DCI and ventriculitis later during the disease course. The amount of daily CSF drainage via EVD had no impact on routine CSF parameters.

Conclusion

Longitudinal CSF characteristics are associated with SAH-related complications.

New Mechanisms and Targets of Subarachnoid Hemorrhage: A Focus on Mitochondria

Spontaneous subarachnoid hemorrhage (SAH) accounts for 5-10% of all strokes and is a subtype of hemorrhagic stroke that places a heavy burden on health care. Despite great progress in surgical clipping and endovascular treatment for ruptured aneurysms, cerebral vasospasm (CVS) and delayed cerebral ischemia (DCI) threaten the long-term outcomes of patients with SAH. Moreover, there are limited drugs available to reduce the risk of DCI and adverse outcomes in SAH patients. New insight suggests that early brain injury (EBI), which occurs within 72 h after the onset of SAH, may lay the foundation for further DCI development and poor outcomes. The mechanisms of EBI mainly include excitotoxicity, oxidative stress, neuroinflammation, blood-brain barrier (BBB) destruction, and cellular death. Mitochondria are a double-membrane organelle, and they play an important role in energy production, cell growth, differentiation, apoptosis, and survival. Mitochondrial dysfunction, which can lead to mitochondrial membrane potential (Δψm) collapse, overproduction of reactive oxygen species (ROS), release of apoptogenic proteins, disorders of mitochondrial dynamics, and activation of mitochondria-related inflammation, is considered a novel mechanism of EBI related to DCI as well as post-SAH outcomes. In addition, mitophagy is activated after SAH. In this review, we discuss the latest perspectives on the role of mitochondria in EBI and DCI after SAH. We emphasize the potential of mitochondria as therapeutic targets and summarize the promising therapeutic strategies targeting mitochondria for SAH.

The incidence of cerebral arterial vasospasm following aneurysmal subarachnoid haemorrhage: a systematic review and meta-analysis

Purpose

To describe a pooled estimated incidence of cerebral arterial vasospasm (aVSP) following aneurysmal subarachnoid haemorrhage (aSAH) and to describe sources of variation in the reported incidence.

Methods

We performed a systematic review and meta-analysis of randomised clinical trials (RCTs) and cohort studies. The primary outcome was the proportion of study participants diagnosed with aVSP. We assessed for heterogeneity based on mode of imaging, indication for imaging, study design and clinical characteristics at a study level.

Results

We identified 120 studies, including 19,171 participants. More than 40 different criteria were used to diagnose aVSP. The pooled estimate of the proportion of patients diagnosed with aVSP was 0.42 (95% CI 0.39 to 0.46, I² = 96.5%). There was no evidence that the incidence aVSP was different, nor that heterogeneity was reduced, when the estimate was assessed by study type, imaging modalities, the proportion of participants with high grade CT scores or poor grade clinical scores. The pooled estimate of the proportion of study participants diagnosed with aVSP was higher in studies with routine imaging (0.47, 95% CI 0.43 to 0.52, I² = 96.5%) compared to those when imaging was performed when indicated (0.30, 95% CI 0.25 to 0.36, I² = 94.0%, p for between-group difference < 0.0005).

Conclusion

The incidence of cerebral arterial vasospasm following aSAH varies widely from 9 to 93% of study participants. Heterogeneity in the reported incidence may be due to variation in the criteria used to diagnose aVSP. A standard set of diagnostic criteria is necessary to resolve the role that aVSP plays in delayed neurological deterioration following aSAH.

PROSPERO registration

CRD42020191895

Supplementary Information

The online version contains supplementary material available at 10.1007/s00234-022-03004-w.

Revisiting the Timeline of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage: Toward a Temporal Risk Profile

BACKGROUND

Delayed cerebral ischemia (DCI) is one of the main determinants of clinical outcome after aneurysmal subarachnoid hemorrhage (SAH). The classical description of risk for DCI over time is currently based on the outdated concept of angiographic vasospasm. The goal of this study was to assess the temporal risk profile of DCI, defined by extended clinical and radiological criteria, as well as the impact the time point of DCI onset has on clinical outcome.

METHODS

All patients with aneurysmal SAH referred to a single tertiary care center between 2010 and 2018 were considered for inclusion. This study was designed as a retrospective cohort analysis and data were extracted from existing patient files. In conscious patients, DCI was diagnosed clinically, and in unconscious patients, diagnosis was based on perfusion computed tomography imaging and multimodal neuromonitoring. Extended Glasgow Outcome Scale scores were assessed after 12 months and compared between patients with early (< day 7) and late (≥ day 7) DCI onset.

RESULTS

The median delay from day of the hemorrhage (day 0) until detection of the first DCI event was 7.0 days, with an interquartile range of 5 days. The probability of DCI development over time demonstrated a bimodal distribution with a peak risk on day 5 (0.084; confidence interval 0.05.5-0.122) and a second peak on day 9 (0.077; confidence interval 0.045-0.120). A total of 27 patients (15.6%) suffered dominant hemispheric or severe bilateral DCI-related infarctions, resulting in the withdrawal of technical life support. Of those, the majority (20 patients, 22.2%) presented with early DCI onset (vs. late onset: 7 patients, 8.4%; p = 0.013).

CONCLUSIONS

The risk profile of DCI over time mirrors the description of angiographic vasospasm; however, it comes with an added timely delay of 1 to 2 days. Early occurrence of DCI (before day 7) is associated with a higher infarct load and DCI-related mortality. Although the exact causal relationship remains to be determined, the time point of DCI onset may serve as an independent prognostic criterion in decision-making.

Geniposide attenuates early brain injury by inhibiting oxidative stress and neurocyte apoptosis after subarachnoid hemorrhage in rats

BACKGROUND

Oxidative stress and neurocyte apoptosis are crucial pathophysiological process in early brain injury (EBI) after subarachnoid hemorrhage (SAH). Geniposide (GNP) has been reported to exert neuroprotective effects by reducing oxidative injury and neurocyte apoptosis. However, the effect of GNP has not been clarified in EBI after SAH. The study was performed to evaluate the neuroprotective effects and mechanisms of GNP in EBI after SAH.

METHODS AND RESULTS

A total of 60 male Wistar rats were randomly divided into five groups. The prechiasmatic cistern SAH model was used in this study. SAH grade was evaluated using a grading system. Neurological function was evaluated using the Garcia scores. Brain edema was measured by the wet-dry method. Blood-brain barrier (BBB) permeability was measured by the extravasation of Evans Blue (EB). The neurocyte apoptosis was observed using TUNEL assay. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD), as well as the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1), glutathione S-transferase (GST) and quinone oxidoreductase-1 (NQO-1) were performed. The results showed that GNP reduced brain edema, attenuated BBB permeability, inhibited neurocyte apoptosis and improved neurological function. Moreover, GNP also decreased the levels of ROS and MDA, elevated Nrf2 expression in the temporal cortex and up-regulated the expression of NQO-1, HO-1 and GST after SAH.

CONCLUSIONS

GNP could ameliorate oxidative stress and neurocyte apoptosis to exert neuroprotective effects by Nrf2 pathway.

The role of L-arginine metabolism in neurocritical care patients

Nitric oxide is an important mediator of vascular autoregulation and is involved in pathophysiological changes after acute neurological disorders. Nitric oxide is generated by nitric oxide synthases from the amino acid L-arginine. L-arginine can also serve as a substrate for arginases or lead to the generation of dimethylarginines, asymmetric dimethylarginine, and symmetric dimethylarginine, by methylation. Asymmetric dimethylarginine is an endogenous inhibitor of nitric oxide synthase and can lead to endothelial dysfunction. This review discusses the role of L-arginine metabolism in patients suffering from acute and critical neurological disorders often requiring neuro-intensive care treatment. Conditions addressed in this review include intracerebral hemorrhage, aneurysmal subarachnoid hemorrhage, and traumatic brain injury. Recent therapeutic advances in the field are described including current randomized controlled trials for traumatic brain injuries and hemorrhagic stroke.

Efficacy of nimodipine in the treatment of subarachnoid hemorrhage: a meta-analysis

Background Subarachnoid hemorrhage (SAH) is an uncommon and serious subtype of stroke, which leads to the loss of the patient's ability to produce and live for many years.

Objective To investigate the clinical effect of nimodipine in the treatment of SAH.

Methods Electronic databases including China National Knowledge Infrastructure (CNKI), VIP, SinoMed, China Master's Theses Full-text Database (CMFD), China Doctoral Dissertations Full-text Database (CDFD), Cochrane Library, PubMed and Embase were searched from 2010 and 2021. All randomized controlled trials evaluating the efficacy of nimodipine in the treatment of SAH were included in our meta-analysis. The patients were divided into control group and treatment group. Meta-analysis was performed with Stata16.0 software.

Results A total of 10 studies were included. Compared with the control group, the treatment group had higher effective rate (OR = 3.21, 95% CI: 2.25, 4.58; p < 0.001), and lower incidence of adverse reactions (OR = 0.35, 95% CI: 0.19, 0.67; p = 0.001). Before treatment, no significant differences were identified in middle cerebral artery blood flow velocity and Glasgow coma scale (GCS) score between the two groups. However, after treatment, the middle cerebral artery blood flow velocity (SMD = −1.36, 95% CI: −2.28, −0.49; p = 0.002) and GCS score (SMD = 1.24, 95% CI: 0.58, 1.89; p < 0.001) in the treatment group were significantly better than those in the control group.

Conclusions Nimodipine is effective in the treatment of SAH, lowering incidence of adverse reactions and therefore improving the prognosis of patients.

TREM2 modulates neuroinflammation with elevated IRAK3 expression and plays a neuroprotective role after experimental SAH in rats

BACKGROUND

The modulation of neuroinflammation is a new direction that may alleviate the early brain injury after subarachnoid hemorrhage (SAH). Brain resident microglia/macrophages (Mi/MΦ) are the key drivers of neuroinflammation. Triggering receptor expressed on myeloid cells 2 (TREM2) has been reported to play a neuroprotective role by activating phagocytosis and suspending inflammatory response in experimental ischemic stroke and intracerebral hemorrhage. This study was designed to investigate the role of TREM2 on neuroinflammation and neuroprotective effects in a rat SAH model.

METHODS

Adult male Sprague-Dawley rats were induced SAH through endovascular perforation. Lentivirus vectors were administered by i.c.v. to induce TREM2 overexpression or knockdown 7 days before SAH induction. Short- and long-term neurobehavioral tests, western blotting, immunofluorescence, enzyme-linked immunosorbent assay, terminal deoxynucleotidyl transferase dUTP nick end labeling and Nissl staining were performed to explore the neuroprotective role of TREM2 after SAH.

RESULTS

The expression of TREM2 elevated in a rat SAH model with a peak at 48 h after SAH and mainly expressed in Mi/MΦ in brain. TREM2 overexpression improved short- and long-term neurological deficits induced by SAH in rats, while TREM2 knockdown worsened neurological dysfunction. The rats with TREM2 overexpressed presented less neuronal apoptosis and more neuronal survival at 48 h after SAH, while the rats with TREM2 knockdown presented on the contrary. TREM2 overexpression manifested activated phagocytosis and suppressed inflammatory response, with the increase of CD206⁺/CD11b⁺ cells and IL-10 expression as well as the decrease of the infiltration of MPO⁺ cells and the expression of TNF-α, IL-1β. While TREM2 knockdown abolished these effects. The protein level of IRAK3, a negative regulatory factor of inflammation, was significantly elevated after TREM2 overexpression and declined after TREM2 knockdown.

CONCLUSIONS

Our research suggested TREM2 played a neuroprotective role and improved the short- and long-term neurological deficits by modulating neuroinflammation after SAH. The modulation on neuroinflammation of TREM2 after SAH was related with the elevated protein level of IRAK3.

Hyperoxia is Dose-Dependently Associated with an Increase of Unfavorable Outcomes in Ventilated Patients with Aneurysmal Subarachnoid Hemorrhage: A Retrospective Cohort Study

Background

Adequate oxygenation in patients with aneurysmal subarachnoid hemorrhage (SAH) is imperative. However, hyperoxia increases formation of reactive oxygen species and may be associated with a dose-dependent toxicity. We postulated a threshold for arterial partial pressure of oxygen (paO₂) above which toxicity effects precipitate and sought to study the effects on 30-day mortality, favorable outcome at discharge and at 3 months, and delayed cerebral ischemia.

Methods

In this retrospective single-center cohort study, patients with SAH and mechanical ventilation > 72 h were included. Oxygen integrals were calculated above the following thresholds: 80, 100, 120, and 150 mm Hg and time-weighted mean paO₂. All calculations were done from admission to end of day 1, day 3, and day 14. We conducted multivariable logistic regression analyses adjusted for age, sex, duration of ventilation, and Hunt and Hess grade. Time-weighted mean paO₂ was categorized by quartiles. Favorable outcome was defined as Glasgow Outcome Scale scores of 4 and 5.

Results

From November 2010 to February 2021, 282 of 549 patients fulfilled the inclusion criteria. Odds ratios for 30-day mortality increased dose dependently and were as follows: 1.07 (95% confidence interval [CI] 1.03–1.11; p = 0.001) for each 1 mm Hg per day above 80 mm Hg; 1.16 (95% CI 1.07–1.27), above 100 mm Hg; 1.36 (95% CI 1.15–1.61), above 120 mm Hg; and 1.59 (95% CI 1.22–2.08), above 150 mm Hg (all p < 0.001) at day 14. For favorable outcome at 3 months, odds ratios were 0.96 (95% CI 0.92–0.99) for each 1 mm Hg per day above 80 mm Hg; 0.90 (95% CI 0.84–0.98), above 100 mm Hg; 0.83 (95% CI 0.72–0.97), above 120 mm Hg; and 0.77 (95% CI 0.61–0.97), above 150 mm Hg (all p < 0.05). For time-weighted mean paO₂, lowest 30-day mortality and highest favorable outcome at 3 months were found in the second quartile (78–85 mm Hg). Thirty-day mortality increased above 93 mm Hg (fourth quartile), with an odds ratio of 3.4 (95% CI 1.4–8.4, p = 0.007). Odds ratios for favorable outcome at 3 months were 0.28 (95% CI 0.12–0.69), 0.27 (95% CI 0.11–0.67), and 0.24 (95% CI 0.10–0.59) for the first, third, and fourth quartiles, respectively (all p < 0.01). No significant association was found at day 1 and day 3, for favorable outcome at discharge, or for delayed cerebral ischemia.

Conclusions

Integrals above the defined paO₂ thresholds were dose-dependently associated with an increase in mortality in ventilated patients with SAH. When we considered time-weighted mean paO₂, unfavorable outcomes and 30-day mortality were more frequent both below and above a certain range. Unfavorable outcomes increased in paO₂ ranges usually defined as normoxia. This emphasizes the necessity to further characterize oxygenation thresholds in ventilated patients with SAH in prospective clinical studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12028-022-01534-y.

Early management of patients with aneurysmal subarachnoid hemorrhage in a hospital with neurosurgical/neuroendovascular facilities: a consensus and clinical recommendations of the Italian Society of Anesthesia and Intensive Care (SIAARTI)-part 2

BACKGROUND

Questions remain on the optimal management of subarachnoid hemorrhage (SAH) patients once they are admitted to the referring center, before and after the aneurysm treatment. To address these issues, we created a consensus of experts endorsed by the Italian Society of Anesthesia and Intensive Care (SIAARTI) to provide clinical guidance regarding this topic. Specifically, in this manuscript (part 2), we aim to provide a list of experts' recommendations regarding the management of SAH patients in a center with neurosurgical/neuroendovascular facilities after aneurysm treatment.

METHODS

A multidisciplinary consensus panel composed by 24 physicians selected for their established clinical and scientific expertise in the acute management of SAH patients with different specializations (anesthesia/intensive care, neurosurgery, and interventional neuroradiology) was created. A modified Delphi approach was adopted.

RESULTS

A total of 33 statements were discussed, voted, and approved. Consensus was reached on 30 recommendations (28 strong and 2 weak). In 3 cases, where consensus could not be agreed upon, no recommendation was provided.

CONCLUSIONS

This consensus provides practical recommendations (and not mandatory standard of practice) to support clinician's decision-making in the management of SAH patients in centers with neurosurgical/neuroendovascular facilities after aneurysm securing.

Outcomes of a Stroke Response Team on the Emergent Management of Intracerebral Hemorrhage

BACKGROUND

Spontaneous intracerebral hemorrhage results in high patient mortality or poor functional outcomes. Early access to specialty care allows for rapid implementation of evidence-based strategies that improve the patient's long-term outcomes.

OBJECTIVES

The aim of this study was to determine the impact of a dedicated stroke response team on timeliness of blood pressure control, administration of anticoagulation reversal agents, and emergency department arrival to a critical care bed.

METHODS

A stroke response team was developed from the neuro intensive care unit that compliments the hospital's current rapid response team. Development of an algorithm guides the implementation of key interventions for intracerebral hemorrhages. Widespread education targeting care of patients with hemorrhagic stroke provided the stroke response team and emergency department staff with knowledge to implement the plan of care.

RESULTS

Baseline time interval data were collected on 70 consecutive patients with intracerebral hemorrhage. After implementation of a dedicated stroke response team, time interval data on 70 consecutive patients with intracerebral hemorrhage were collected for comparison with the baseline measurement. A significant decrease was seen in the time to control the patient's systolic blood pressure (median of 130 to 56 minutes, P = .000) and emergency department arrival to a critical care bed (240 to 132 minutes, P = .000). Patient arrival to anticoagulation reversal agent administration decreased from a mean of 98 to 72 minutes (P = .32).

DISCUSSION

Implementation of a stroke response team increased the knowledge of the care team, improved the timeliness of blood pressure control, and decreased the time for emergency department arrival to a critical care bed, and to anticoagulation reversal agent administration.

A Systematic Review and Meta-Analysis of Serum Concentrations of Ischaemia-Modified Albumin in Acute Ischaemic Stroke, Intracerebral Haemorrhage, and Subarachnoid Haemorrhage

The identification of robust circulating biomarkers of stroke may improve outcomes. We conducted a systematic review and meta-analysis of serum concentrations of ischaemia-modified albumin (IMA) in subjects with or without acute ischaemic stroke (AIS), intracerebral haemorrhage (ICH), and subarachnoid haemorrhage (SAH). We searched PubMed, Web of Science, Scopus, and Google Scholar from inception to March 2022. Risk of bias and certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and GRADE, respectively. In 17 studies, IMA concentrations were significantly higher in patients with AIS (standard mean difference, SMD = 2.52, 95% CI 1.92 to 3.12; p < 0.001), ICH (SMD = 3.13, 95% CI 1.00 to 5.25; p = 0.004), and SAH (SMD = 4.50, 95% CI 0.91 to 7.01; p = 0.014) vs. controls (very low certainty of evidence). In AIS, the effect size was associated with the male gender, and was relatively larger in studies conducted in Egypt and India and those using enzyme-linked immunosorbent assays. IMA concentrations were progressively higher, by direct comparison, in SAH, ICH, and AIS. In sensitivity analysis, the pooled SMDs were not altered when individual studies were sequentially removed. Our meta-analysis suggests that IMA concentrations might be useful to diagnose stroke and discriminate between AIS, ICH, and SAH (PROSPERO registration number: CRD42021320535).

Mesenchymal Stem Cell-Derived Extracellular Vesicles Alleviate M1 Microglial Activation in Brain Injury of Mice With Subarachnoid Hemorrhage via microRNA-140-5p Delivery

BACKGROUND

It is documented that mesenchymal stem cells (MSCs) secrete extracellular vesicles (EVs) to modulate subarachnoid hemorrhage (SAH) development. miR-140-5p expression has been detected in MSC-derived EVs, while the mechanism of MSC-derived EVs containing miR-140-5p in SAH remains unknown. We aim to fill this void by establishing SAH mouse models and extracting MSCs and MSC-EVs.

METHODS

After ALK5 was silenced in SAH mice, neurological function was evaluated, neuron apoptosis was detected by TdT-mediated dUTP-biotin nick end labeling with NeuN staining, and expression of serum inflammatory factors (interleukin-6, interleukin-1β, and tumor necrosis factor-α) was determined by enzyme-linked immunosorbent assay. The effect of ALK5 on NOX2 expression was assessed by western-blot analysis. Targeting the relationship between miR-140-5p and ALK5 was evaluated by dual luciferase assay. Following extraction of MSCs and MSC-EVs, EVs and miR-140-5p were labeled by PKH67 and Cy3, respectively, to identify the transferring of miR-140-5p by MSC-EVs. SAH mice were treated with EVs from miR-140-5p mimic/inhibitor-transfected MSCs to detect effects of MSC-EV-miR-140-5p on brain injury and microglial polarization.

RESULTS

ALK5 silencing increased the neurological score and reduced neuron apoptosis and neuroinflammation in SAH mice. ALK5 silencing inhibited M1 microglia activation by inactivating NOX2. ALK5 was a target gene of miR-140-5p. MSC-derived EVs contained miR-140-5p and transferred miR-140-5p into microglia. MSC-EV-delivered miR-140-3p reduced ALK5 expression to contribute to repression of brain injury and M1 microglia activation in SAH mice.

CONCLUSIONS

MSC-derived EVs transferred miR-140-5p into microglia to downregulate ALK5 and NOX2, thus inhibiting M1 microglia activation in SAH mice.

Spreading depolarizations in ischaemia after subarachnoid haemorrhage, a diagnostic phase III study

Focal brain damage after aneurysmal subarachnoid haemorrhage predominantly results from intracerebral haemorrhage, and early and delayed cerebral ischaemia. The prospective, observational, multicentre, cohort, diagnostic phase III trial, DISCHARGE-1, primarily investigated whether the peak total spreading depolarization-induced depression duration of a recording day during delayed neuromonitoring (delayed depression duration) indicates delayed ipsilateral infarction. Consecutive patients (n = 205) who required neurosurgery were enrolled in six university hospitals from September 2009 to April 2018. Subdural electrodes for electrocorticography were implanted. Participants were excluded on the basis of exclusion criteria, technical problems in data quality, missing neuroimages or patient withdrawal (n = 25). Evaluators were blinded to other measures. Longitudinal MRI, and CT studies if clinically indicated, revealed that 162/180 patients developed focal brain damage during the first 2 weeks. During 4.5 years of cumulative recording, 6777 spreading depolarizations occurred in 161/180 patients and 238 electrographic seizures in 14/180. Ten patients died early; 90/170 developed delayed infarction ipsilateral to the electrodes. Primary objective was to investigate whether a 60-min delayed depression duration cut-off in a 24-h window predicts delayed infarction with >0.60 sensitivity and >0.80 specificity, and to estimate a new cut-off. The 60-min cut-off was too short. Sensitivity was sufficient [= 0.76 (95% confidence interval: 0.65-0.84), P = 0.0014] but specificity was 0.59 (0.47-0.70), i.e. <0.80 (P < 0.0001). Nevertheless, the area under the receiver operating characteristic (AUROC) curve of delayed depression duration was 0.76 (0.69-0.83, P < 0.0001) for delayed infarction and 0.88 (0.81-0.94, P < 0.0001) for delayed ischaemia (reversible delayed neurological deficit or infarction). In secondary analysis, a new 180-min cut-off indicated delayed infarction with a targeted 0.62 sensitivity and 0.83 specificity. In awake patients, the AUROC curve of delayed depression duration was 0.84 (0.70-0.97, P = 0.001) and the prespecified 60-min cut-off showed 0.71 sensitivity and 0.82 specificity for reversible neurological deficits. In multivariate analysis, delayed depression duration (β = 0.474, P < 0.001), delayed median Glasgow Coma Score (β = -0.201, P = 0.005) and peak transcranial Doppler (β = 0.169, P = 0.016) explained 35% of variance in delayed infarction. Another key finding was that spreading depolarization-variables were included in every multiple regression model of early, delayed and total brain damage, patient outcome and death, strongly suggesting that they are an independent biomarker of progressive brain injury. While the 60-min cut-off of cumulative depression in a 24-h window indicated reversible delayed neurological deficit, only a 180-min cut-off indicated new infarction with >0.60 sensitivity and >0.80 specificity. Although spontaneous resolution of the neurological deficit is still possible, we recommend initiating rescue treatment at the 60-min rather than the 180-min cut-off if progression of injury to infarction is to be prevented.

High Neutrophil-to-Albumin Ratio Predicts Postoperative Pneumonia in Aneurysmal Subarachnoid Hemorrhage

Background and Aim

There is still an absence of objective and easily accessible biomarkers despite the variety of risk factors associated with postoperative pneumonia (POP) in patients with aneurysmal subarachnoid hemorrhage (aSAH). In the present study, we have thus evaluated the relationship between the neutrophil-to-albumin ratio (NAR) and POP in patients with aSAH.

Methods

Several consecutive patients (n = 395) who had undergone clipping or coiling of the aneurism were retrospectively assessed, of which we were able to analyze the existing population data and the related baseline variables. The patients were divided into POP and revealed not to occur. To identify independent predictors, we used the recipient operation feature (receiver operating characteristic, ROC) curve and a logic regression analysis.

Results

This cohort was based on POP that occurred in 78 out of the 395 patients (19.7%), and these revealed a significantly higher NAR than those without (0.31 [0.25–0.39] vs. 0.23 [0.18–0.28]; p &lt; 0.001). On the other hand, a multivariate logistic regression analysis showed that NAR (odds ratio = 1.907; 95% confidence interval, 1.232–2.953; p = 0.004) was independently associated with a POP after due adjustment for confounders. Moreover, the predictive performances of NAR for POP were also significant (area under the ROC curve [95% CI] 0.775 [0.717–0.832]; p &lt; 0.001).

Conclusion

The elevation of NAR at admission in patients with aSAH might help predict POP.

Intracranial Venous Alteration in Patients With Aneurysmal Subarachnoid Hemorrhage: Protocol for the Prospective and Observational SAH Multicenter Study (SMS)

Background

Arterial vasospasm has been ascribed as the responsible etiology of delayed cerebral infarction in patients with aneurysmal subarachnoid hemorrhage (aSAH), but other neurovascular structures may be involved. We present the protocol for a multicenter, prospective, observational study focused on analyzing morphological changes in cerebral veins of patients with aSAH.

Methods and Analysis

In a retrospective arm, we will collect head arterial and venous CT angiograms (CTA) of 50 patients with aSAH and 50 matching healthy controls at days 0–2 and 7–10, comparing morphological venous changes. A multicenter prospective observational study will follow. Patients aged ≥18 years of any gender with aSAH will be enrolled at 9 participating centers based on the predetermined eligibility criteria. A sample size of 52 aSAH patients is expected, and 52 healthy controls matched per age, gender, and comorbidities will be identified. For each patient, sequential CTA will be conducted upon admission (day 0–2), at 7–10 days, and at 14–21 days after aSAH, evaluating volumes and morphology of the cerebral deep veins and main cortical veins. One specialized image collecting center will analyze all anonymized CTA scans, performing volumetric calculation of targeted veins. Morphological venous changes over time will be evaluated using the Dice coefficient and the Jaccard index and scored using the Boeckh–Behrens system. Morphological venous changes will be correlated to clinical outcomes and compared between patients with aSAH and healthy-controls, and among groups based on surgical/endovascular treatments for aSAH.

Ethics and Dissemination

This protocol has been approved by the ethics committee and institutional review board of Ethikkommission, SALK, Salzburg, Austria, and will be approved at all participating sites. The study will comply with the Declaration of Helsinki. Written informed consent will be obtained from all enrolled patients or their legal tutors. We will present our findings at academic conferences and peer-reviewed journals.

Approved Protocol Version and Registration

Version 2, 09 June 2021.