Aneurysmal Subarachnoid Hemorrhage: the Last Decade

The oral microbiota: new insight into intracranial aneurysms

BACKGROUND

Intracranial aneurysms (IAs) are a significant clinical concern, with detection rates increasing due to advances in imaging technologies. However, precise mechanisms underlying their pathophysiology remain incompletely understood. Recent evidence suggests a pivotal role of oral microbiota dysbiosis, particularly periodontal pathogens, in systemic inflammation that may contribute to IA development and rupture.

OBJECTIVE

This review aims to critically evaluate the association between oral microbiota dysbiosis and the pathogenesis of IAs, with a focus on the molecular and immunological mechanisms by which oral pathogens influence vascular pathology.

METHODS

We conducted a comprehensive analysis of the literature regarding the impact of oral microbial dysbiosis on IA pathophysiology, emphasizing the role of specific pathogenic species, such as Porphyromonas gingivalis. The review explores how these pathogens may mediate chronic inflammation through hematogenous spread, gut microbiome alterations, and neuroinflammatory processes, leading to vascular remodeling and cerebrovascular instability.

RESULTS

The findings suggest that oral microbial dysbiosis, particularly the presence of pathogenic bacteria, is implicated in the systemic inflammatory response that exacerbates the structural integrity of the cerebrovascular wall. Chronic inflammatory states induced by oral pathogens contribute to extracellular matrix degradation, impaired vascular remodeling, and an increased susceptibility to IA rupture.

CONCLUSIONS

The findings highlight the importance of maintaining oral microbiota homeostasis as a potential therapeutic target for preventing IAs. Interventions aimed at restoring oral microbial balance may represent a novel strategy for reducing the burden of IA formation and rupture, highlighting the need for an integrated approach to oral health and IAs prevention.

Mitophagy in acute central nervous system injuries: regulatory mechanisms and therapeutic potentials

Acute central nervous system injuries, including ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, and spinal cord injury, are a major global health challenge. Identifying optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent priorities. Mitochondria are susceptible to damage after acute central nervous system injury, and this leads to the release of toxic levels of reactive oxygen species, which induce cell death. Mitophagy, a selective form of autophagy, is crucial in eliminating redundant or damaged mitochondria during these events. Recent evidence has highlighted the significant role of mitophagy in acute central nervous system injuries. In this review, we provide a comprehensive overview of the process, classification, and related mechanisms of mitophagy. We also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate mitophagy. In the final section of this review, we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

Switching Off Vascular MAPK Signaling: A Novel Strategy to Prevent Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage

Patients who initially survive the rupture and repair of a brain aneurysm often take a devastating turn for the worse some days later and die or suffer permanent neurologic deficits. This catastrophic sequela is attributed to a delayed phase of global cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH), but we lack effective treatment. Here we present our view, based on 20 years of research, that the initial drop in blood flow at the time of rupture triggers genomic responses throughout the brain vasculature that manifest days later as increased vasoconstriction and decreased cerebral blood flow. We propose a novel treatment strategy to prevent DCI by early inhibition of the vascular mitogen-activated protein kinase (MAPK) pathway that triggers expression of vasoconstrictor and inflammatory mediators. We summarize evidence from experimental SAH models showing early treatment with MAPK inhibitors "switches off" these detrimental responses, maintains flow, and improves neurological outcome. This promising therapy is currently being evaluated in clinical trials.

Development of a non-contrast CT-based radiomics nomogram for early prediction of delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage

BACKGROUNDS

Delayed cerebral ischemia (DCI) is a significant complication following aneurysmal subarachnoid hemorrhage (aSAH), leading to poor prognosis and high mortality. This study developed a non-contrast CT (NCCT)-based radiomics nomogram for early DCI prediction in aSAH patients.

METHODS

Three hundred seventy-seven aSAH patients were included in this retrospective study. Radiomic features from the baseline CTs were extracted using PyRadiomics. Feature selection was conducted using t-tests, Pearson correlation, and Lasso regression to identify those features most closely associated with DCI. Multivariable logistic regression was used to identify independent clinical and demographic risk factors. Eight machine learning algorithms were applied to construct radiomics-only and radiomics-clinical fusion nomogram models.

RESULTS

The nomogram integrated the radscore and three clinically significant parameters (aneurysm and aneurysm treatment and admission Hunt-Hess score), with the Support Vector Machine model yielding the highest performance in the validation set. The radiomics model and nomogram produced AUCs of 0.696 (95% CI: 0.578-0.815) and 0.831 (95% CI: 0.739-0.923), respectively. The nomogram achieved an accuracy of 0.775, a sensitivity of 0.750, a specificity of 0.795, and an F1 score of 0.750.

CONCLUSION

The NCCT-based radiomics nomogram demonstrated high predictive performance for DCI in aSAH patients, providing a valuable tool for early DCI identification and formulating appropriate treatment strategies.

CLINICAL TRIAL NUMBER

Not applicable.

Construction of a nomogram model for predicting delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage patients

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe cerebrovascular disease.This retrospective two-center cohort study aimed to construct a nomogram model for predicting delayed cerebral ischemia (DCI) in aSAH patients using LASSO- logistic regression. A total of 604 aSAH patients were included. We collected serological indicators of patients at admission. Lasso and multivariate logistic regression analysis and was performed to screen variables and constructed the independent predictors into a nomogram using R language. After LASSO and multivariate logistic regression, Alcoholism, PLT, Na, and APTT were identified as independent risk factors for DCI. A nomogram model was then developed based on these factors. The model showed good predictive performance in both the training set (AUC = 0.703) and the validation set (AUC = 0.633), along with stable calibration and favorable clinical benefits. Alcoholism, PLT, Na, and APTT may be independent predictors of DCI in aSAH patients. This nomogram can potentially help clinicians assess the risk of DCI in aSAH patients at an early stage and implement timely preventive and treatment measures.

External validation of outcome prediction scores for aneurysmal subarachnoid hemorrhage in a real-world setting: a monocentric experience

OBJECTIVE

To evaluate the applicability and performance of predictive scoring systems for outcome prediction in a real-world cohort of patients with aneurysmatic Subarachnoid Hemorrhage (aSAH), trying to avoid overtreatment and reducing their impact on Intensive Care Unit (ICU) overcrowding.

METHODS

All adult patients diagnosed with aSAH from January 2018 to December 2023 were retrospectively collected in a single centre. Predictive scores such as SAFIRE, HATCH, HAIR, and Nutshell were calculated, and their performance was analyzed using receiver operating characteristic (ROC) analysis. Kaplan-Meier curves were estimated by dividing the cohort according to the calculated scores.

RESULTS

Of 274 patients, 72.3% underwent endovascular treatment, 16.1% surgical clipping, and 11.7% received no treatment. The 30-day and overall mortality rates were 27.7% and 41.2%, respectively. ICU admission occurred in 74.1% of cases, with a mortality rate of 38.4%. The HAIR and the Nutshell scores performed well in predicting 30-day mortality (AUC: 0.812 and 0.749, respectively), while the SAFIRE and the HATCH scores demonstrated excellent predictive value for poor functional outcomes (AUC: 0.866 and 0.886 at discharge; 0.825 and 0.83 at one year, respectively). Patients in the worst SAFIRE group (> 15) exhibited mortality rates exceeding 89% at follow-up, with universally poor outcomes.

CONCLUSION

The SAFIRE and the HATCH scores are reliable tools for predicting outcomes in aSAH patients, with SAFIRE offering particular value at admission. Their implementation in surgical practice could improve resource allocation, guide ethical decision-making, and reduce ICU burden, especially for patients with severe aSAH and limited potential for recovery.

The effect of Fibulin-5 on early brain injury after subarachnoid hemorrhage in mice

Early brain injury (EBI) is an important cause that determines outcomes after aneurysmal subarachnoid hemorrhage (SAH). Our recent clinical study reported that a high concentration of plasma fibulin-5 (FBLN5), one of matricellular proteins, was associated with poor outcomes after SAH. The aim of this study was to investigate whether and how FBLN5 was associated with EBI during an acute phase of SAH in mice. C57BL/6 male mice underwent sham or filament perforation SAH modeling, and vehicle or four dosages (0.001, 0.01, 0.1, and 1 μg) of short or long recombinant FBLN5 (rFBLN5) were randomly administrated by an intracerebroventricular injection. Neurobehavioral test, measurements of brain water content, immunohistochemical staining, and Western blotting were performed to evaluate EBI 24 h after SAH. Short rFBLN5 had no significant effects on EBI, but administration of long rFBLN5 containing an arginine-glycine-aspartic acid motif improved neurobehavior functions depending on the dosages, without affecting brain edema. Administration of long rFBLN5 also reduced cleaved caspase-3-dependent neuronal apoptosis, associated with the inhibition of post-SAH upregulation of transforming growth factor-β1, but no significant changes in the expression level of Smad 2/3, mitogen-activated protein kinases, and another matricellular protein tenascin-C. Although further research is required to clarify the detailed mechanism, this study demonstrated for the first time that FBLN5 played a protective role against neuronal apoptosis in an acute phase of experimental SAH.

Identification of Risk Factors Influencing Hemorrhage Volume in Aneurysmal Subarachnoid Hemorrhage: A Multicenter Retrospective Study

OBJECTIVE

This multicenter retrospective study aimed to identify significant risk factors influencing hemorrhage volume in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

A total of 891 patients diagnosed with SAH were included from multiple medical centers. Data encompassing demographic characteristics, medical history, clinical parameters at admission, and radiographic findings were collected and analyzed. Univariate and multivariate logistic regression analyses were conducted to investigate associations between various risk factors and hemorrhage volume.

RESULTS

This study identifies several factors significantly associated with increased hemorrhage volume in patients with subarachnoid hemorrhage (SAH). Multivariate analysis revealed that diabetes (P = 0.022), hypertension (P = 0.047), and saccular aneurysm morphology (P = 0.008) were independent risk factors for high hemorrhage volume. Additionally, larger aneurysm size (maximum diameter: P = 0.007, neck diameter: P = 0.021) and higher systolic blood pressure after onset (P = 0.002) were also significant predictors of increased hemorrhage volume. Factors such as age (P = 0.05) and time interval to the first CT scan (P = 0.022) were found to be associated with hemorrhage volume in univariate analysis but did not maintain independent significance in multivariate regression.

CONCLUSION

This study highlights key risk factors, including diabetes, hypertension, and saccular aneurysm morphology, which independently contribute to higher hemorrhage volume in SAH patients. Management strategies focusing on early detection and control of these factors may improve clinical outcomes by reducing the risk of hemorrhagic complications. While other factors such as age and time interval to the first CT scan were associated with hemorrhage volume, they did not demonstrate independent causality in the multivariate analysis, suggesting that their role in hemorrhage volume may be secondary or context-dependent.

Revealing shared molecular and mechanistic signatures between intracranial aneurysms and abdominal aortic aneurysms: a comprehensive genomic analysis

Intracranial aneurysms (IAs) and abdominal aortic aneurysms (AAAs) are both vascular diseases that are closely linked. However, the pathogenesis underlying the co-occurrence of IAs and AAAs remains poorly understood. This study aims to identify key biomarkers that shed light on the molecular mechanisms connecting these two diseases using bioinformatics analysis. Gene expression profiles (GSE122897, GSE237229) were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) common to both IAs and AAAs were identified and subjected to functional enrichment analysis. The Cytoscape cytoHubba plugin was used to identify hub genes, and their predictive ability was evaluated using the receiver operating characteristic (ROC) curve. Additionally, immune infiltration analyses and single-gene gene set enrichment analysis (GSEA) were conducted for the hub genes. A total of 46 DEGs were identified, including 40 upregulated genes and 6 downregulated genes. The common DEGs were found to be involved in extracellular matrix structural constituents, collagen fibril organization, and regulation of basic cellular processes. ITGA11 was identified as a key gene implicated in the comorbidity of IAs and AAAs, with its upregulation strongly associated with plasma cells. Furthermore, in both IAs and AAAs, glycosaminoglycan biosynthesis of extracellular matrix components and immune-related diseases were significantly linked to the high expression of ITGA11. Our findings suggest that the comorbidity of IAs and AAAs may be driven by shared inflammatory and immune response mechanisms, with ITGA11 emerging as a potential biomarker for this co-occurrence.

Identification of pivotal genes and regulatory networks associated with SAH based on multi-omics analysis and machine learning

Subarachnoid hemorrhage (SAH) is a disease with high mortality and morbidity, and its pathophysiology is complex but poorly understood. To investigate the potential therapeutic targets post-SAH, the SAH-related feature genes were screened by the combined analysis of transcriptomics and metabolomics of rat cortical tissues following SAH and proteomics of cerebrospinal fluid from SAH patients, as well as WGCNA and machine learning. The competitive endogenous RNAs (ceRNAs) and transcription factors (TFs) regulatory networks of the feature genes were constructed and further validated by molecular biology experiments. A total of 1336 differentially expressed proteins were identified, including 729 proteins downregulated and 607 proteins upregulated. The immune microenvironment changed after SAH and the changement persisted at SAH 7d. Through multi-omics and bioinformatics techniques, five SAH-related feature genes (A2M, GFAP, GLIPR2, GPNMB, and LCN2) were identified, closely related to the immune microenvironment. In addition, ceRNAs and TFs regulatory networks of the feature genes were constructed. The increased expression levels of A2M and GLIPR2 following SAH were verified, and co-localization of A2M with intravascular microthrombus was demonstrated. Multiomics and bioinformatics tools were used to predict the SAH associated feature genes confirmed further through the ceRNAs and TFs regulatory network development. These molecules might play a key role in SAH and may serve as potential biological markers and provide clues for exploring therapeutic options.

Acute Neurovascular Inflammatory Profile in Patients with Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening condition that results from intracranial aneurysm rupture, leading to the accumulation of blood between the arachnoid and pia mater. The blood breakdown products and damage-associated molecule patterns (DAMPs), which are released as a result of vascular and cellular compromise following aneurysm rupture, elicit local endothelial reactions leading to the narrowing of cerebral arteries and ischemia. In addition, vascular inflammation, characterized by activated endothelial cells, perpetuates disruption of the neurovascular unit and the blood-brain barrier. The uncertain prognosis of aSAH patients contributes to the necessity of a fluid biomarker that can serve as a valuable adjunct to radiological and clinical evaluation. Limited studies have investigated vascular inflammation and angiogenic protein expression following aSAH. Reliable markers of the vascular inflammatory and angiogenic response associated with aSAH may allow for the earlier detection of patients at risk for complications and aid in the identification of novel pharmacologic targets. We investigated whether vascular inflammatory and angiogenesis signaling proteins may serve as potential biomarkers of aSAH. Serum and cerebrospinal fluid (CSF) from fifteen aSAH subjects and healthy age-matched controls as well as hydrocephalus (CSF) no-aneurysm controls were evaluated for levels of vascular inflammatory and angiogenesis proteins. Protein measurement was carried out using electrochemiluminescence. The area under the curve (AUC) was calculated using receiver operating characteristics (ROC) to obtain information on biomarker reliability, specificity, sensitivity, cut-off points, and likelihood ratio. In addition, patients were grouped by Glasgow Outcome Score-Extended at 3 months post-injury to determine the correlation between vascular inflammatory protein levels and clinical outcome measures. aSAH subjects demonstrated elevated vascular inflammatory protein levels in serum and CSF when compared to controls. Certain vascular injury and angiogenic proteins were found to be promising biomarkers of inflammatory response in aSAH in the CSF and serum. In particular, elevated levels of serum amyloid-alpha (SAA) were found to be correlated with unfavorable outcomes following aSAH. Determination of these protein levels in CSF and serum in aSAH may be utilized as reliable biomarkers of inflammation in aSAH and used clinically to monitor patient outcomes.

Tremella fuciformis Polysaccharides Alleviate Early Brain Injury in Experimental Subarachnoid Hemorrhage by Inhibiting the KDR-Mediated P38 MAPK/NF-κB Pathway

Subarachnoid hemorrhage (SAH) is associated with high mortality and morbidity rates. In its early stages, a substantial influx of blood into the subarachnoid space triggers excessive activation of microglia, which markedly contributes to early brain injury (EBI), a pivotal determinant of poor prognosis. Tremella fuciformis polysaccharides (TFPSs), as acidic heteropolysaccharides from the fruiting bodies of Tremella, exhibit robust anti-inflammatory characteristics and many biological properties. Nonetheless, the impact of TFPSs on EBI after SAH has yet to be reported, and the molecular mechanisms underlying these effects remain elusive. We used in vivo and in vitro models to study the effects of TFPSs on microglia post-SAH. Network pharmacology analysis was used to predict the targets of TFPSs and the pathways through which it exerts its therapeutic effects. These predictions were subsequently corroborated through flow cytometry, Western blotting, immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), and quantitative real‑time polymerase chain reaction, both in vivo and in vitro. After 24 h post-SAH, TFPS-treated mice presented improved neurological function and reduced cerebral edema. TFPSs reversed microglial activation, enhanced phagocytic ability, and reduced neuronal apoptosis. Network pharmacology identified KDR as a potential target of TFPSs, with the P38 MAPK pathway as the downstream pathway. TFPSs attenuated KDR expression, inhibited the P38 MAPK/NF-κB pathway, reduced inflammatory cytokine expression, and increased microglial phagocytic capacity post-SAH. This investigation revealed that TFPSs may ameliorate EBI after SAH, potentially via the regulation of the KDR-mediated P38 MAPK/NF-κB pathway and phagocytic function.

Intranasal administration of stem cell-derived exosome alleviates cognitive impairment against subarachnoid hemorrhage

INTRODUCTION

Brain damage caused by subarachnoid hemorrhage (SAH) currently lacks effective treatment, leading to stagnation in the improvement of functional outcomes for decades. Recent studies have demonstrated the therapeutic potential of exosomes released from mesenchymal stem cells (MSC), which effectively attenuate neuronal apoptosis and inflammation in neurological diseases. Due to the challenge of systemic dilution associated with intravenous administration, intranasal delivery has emerged as a novel approach for targeting the brain. In this study, we investigate the effects of intranasally administered MSC-derived exosomes in a SAH animal model and elucidate their mode of action.

METHODS

Exosomes were isolated from the cell supernatants of amnion-derived MSC. SAH was induced in 8-week-old Sprague-Dawley rats using an autologous blood prechiasmatic cistern injection model. A total of 1.2 × 1010 particles of exosomes in 200 μL of PBS or PBS alone were intranasally administered immediately and 24 h post-injury. Neurological function was assessed up to 7 days after injury, and histological analysis was performed to evaluate their anti-apoptotic and anti-inflammatory effects. The biodistribution of exosomes was assessed using PET/CT imaging of 64Cu labeled exosome. In vitro analyses were performed using primary glial cells and cell lines to evaluate the anti-inflammatory effects of the exosomes.

RESULTS

Animals treated with exosomes exhibited significant improvement in cognitive function compared with PBS treated animal. Apoptotic cells and inflammation were reduced for the exosome group in the hippocampal CA1 area and in cortex, resulting in better neuronal cell survival. Blood brain barrier permeability was also preserved in the exosome group. Nuclear imaging revealed that exosomes were primarily transferred to the olfactory nerve and cerebrum; furthermore, exosomes were also observed in the trigeminal nerve and brainstem, where exosomes were co-localized with microglia and with endothelial cells. In vitro assessment showed that exosome administration ameliorated inflammation and prevented the death of glial cells.

CONCLUSIONS

MSC-derived exosomes were successfully transferred into the brain through intranasal administration and alleviated brain damage following SAH.

Methylated MFGE8 Promotes Early Brain Injury After Subarachnoid Hemorrhage and Inhibiting Autophagy of Nerve Cell

BACKGROUND

Spontaneous subarachnoid hemorrhage (SAH) is a relatively common clinical hemorrhagic stroke crisis. The important role of early brain injury (EBI) and autophagy in SAH has been increasingly recognized in recent years. This study aims to investigate the function and the undergoing mechanism of MFGE8 in EBI after SAH.

METHODS

SAH model was established using C57BL/6 mice, and the SAH cell model was constructed by oxy-hemoglobin (Oxy-Hb) induced BV2 and SH-SY5Y co-culture system. Various methods were used to detect EBI and autophagy after SAH in mouse/cell lines, including mouse neurological function score, wet/dry method, HE and Evans blue staining, etc. The effect on EBI was explored after knockdown or overexpression of key genes DNMT1, MFGE8, and P2X7R. MSP was used to detect the methylation of MFGE8 promoter region, and ChIP was used to detect the binding relationship between DNMT1 and MFGE8 promoter region.

RESULTS

The results showed that the activation of autophagy attenuates EBI in SAH mice. Increased level of DNMT1 and decreased level of MFGE8 were observed in brain tissues of SAH mice. Knockdown of DNMT1 or overexpression of MFGE8 attenuates EBI in mice by promoting autophagy. At the same time, we found that DNMT1 promotes methylation of MFGE8 promoter region and suppresses its protein levels. MFGE8 downregulates P2X7R levels and subsequently activates PI3k/Akt/mTOR axis, promotes autophagy, and attenuates EBI in SAH mice.

CONCLUSION

DNMT1 promotes the methylation of MFGE8 promoter region and downregulates MFGE8 level; restoring MFGE8 downregulates P2X7R, and promotes autophagy by limiting the activation of PI3k/Akt/mTOR, thus exerting a protective effect on brain tissue of SAH mice.

HIGHLIGHTS

• High expression of DNMT1 and P2X7R and low expression of MFGE8 were observed in SAH mice. • Activation of autophagy reduces EBI after SAH in mice. • DNMT1/MFGE8 reduces autophagy in EBI after SAH in both mouse and cell models. • DNMT1 targets the MFGE8 promoter to upregulate its methylation level. • MFGE8 inhibits P2X7R to activate PI3k/AKT/mTOR pathway and autophagy, thus inhibiting EBI after SAH.

Olfactory mucosa mesenchymal stem cell-derived exosomes protect against neuroinflammation after subarachnoid hemorrhage by activating mitophagy

Subarachnoid hemorrhage (SAH) can lead to significant acute neuroinflammation, with treatment outcomes often being inadequate. Olfactory mucosa mesenchymal stem cells (OM-MSCs) have promising therapeutic potential in nerve regeneration and functional recovery. This investigation sought to elucidate the functional mechanisms through which exosomes derived from OM-MSCs provide protection against neuroinflammation following SAH. Mouse OM-MSCs and their exosomes were isolated and characterized using various techniques, including transmission electron microscopy, immunofluorescence staining, Western blotting, flow cytometry, and nanoparticle tracking analysis. Hemin-induced HT22 cells were subsequently utilized to assess the impact of OM-MSC-derived exosomes on the inflammatory response, apoptosis, and mitophagy through ELISAs, Western blotting, qPCR, flow cytometry, and immunofluorescence staining. The impacts of exosomes on neuroinflammation and neuronal damage in SAH model mice were assessed using qPCR, ELISAs, Western blotting, immunofluorescence staining, and TUNEL staining. Exosomes derived from OM-MSCs had the capacity to reduce the levels of proinflammatory factors (IL-6, IL-1β, and TNF-α) and promote apoptosis in hemin-induced HT22 cells. Exosomes alleviated neuroinflammation and neuronal injury post-SAH, as evidenced by the increase in modified Garcia scores, reduction in the brain water content, decrease in blood-brain barrier permeability, decreases in inflammatory marker levels, and reduction in apoptosis rates. Notably, the protective effects of exosomes derived from OM-MSCs on neuroinflammation and apoptosis, both in vitro and in vivo, were mediated via the activation of mitophagy. These findings provide a fresh perspective for subsequent clinical research in the domain of prevention and treatment strategies.

Machine Learning in Predicting the Cognitive Improvement of Ventriculoperitoneal Shunt for Chronic Normal Pressure Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Chronic normal pressure hydrocephalus (CNPH) is a recognized sequela of aneurysmal subarachnoid hemorrhage (ASAH). Ventriculoperitoneal shunt (VPS) is a conventional treatment for hydrocephalus, though its effectiveness for CNPH post-ASAH remains unclear.

METHODS

We included ASAH patients with CNPH who underwent VPS surgery. Changes in the modified Rankin Scale (mRS) before and after surgery were analyzed to evaluate VPS benefits. The least absolute shrinkage and selection operator identified relevant variables and predictive models were constructed using 8 supervised machine learning algorithms to assess VPS benefit.

RESULTS

Among 75 patients (39 males and 36 females), 48 (64%) benefited from VPS, while 27 (36%) did not. The beneficial group showed a longer disease course, higher cerebrospinal fluid (CSF) pressure, lower red and white blood cell counts in CSF, and lower modified Fisher (MF) and Hunt-Hess (HH) grades compared to the nonbeneficial group. Univariate logistic regression analysis indicated that disease course, CSF pressure, red blood cell/white blood cell (WBC) counts in CSF, WBC count in blood, MF grade, HH grade, and preoperative mRS were associated with favorable VPS outcomes. The extreme gradient boosting (XGB) model demonstrated the highest area under the curve of 0.946 and lowest residual error. A nomogram was subsequently developed and demonstrated a satisfactory performance.

CONCLUSIONS

VPS benefits in CNPH patients after ASAH were associated with disease course, CSF pressure, red blood cell/WBC counts in CSF, WBC count in blood, MF and HH grades, and preoperative mRS. The XGB model demonstrated optimal predictive performance, with an area under the curve of 0.946.

Therapeutic potential of stem cells in subarachnoid hemorrhage

Aneurysm rupture can result in subarachnoid hemorrhage, a condition with potentially severe consequences, such as disability and death. In the acute stage, early brain injury manifests as intracranial pressure elevation, global cerebral ischemia, acute hydrocephalus, and direct blood-brain contact due to aneurysm rupture. This may subsequently cause delayed cerebral infarction, often with cerebral vasospasm, significantly affecting patient outcomes. Chronic complications such as brain volume loss and chronic hydrocephalus can further impact outcomes. Investigating the mechanisms of subarachnoid hemorrhage-induced brain injury is paramount for identifying effective treatments. Stem cell therapy, with its multipotent differentiation capacity and anti-inflammatory effects, has emerged as a promising approach for treating previously deemed incurable conditions. This review focuses on the potential application of stem cells in subarachnoid hemorrhage pathology and explores their role in neurogenesis and as a therapeutic intervention in preclinical and clinical subarachnoid hemorrhage studies.

Inhibition of GPR17/ID2 Axis Improve Remyelination and Cognitive Recovery after SAH by Mediating OPC Differentiation in Rat Model

Myelin sheath injury contributes to cognitive deficits following subarachnoid hemorrhage (SAH). G protein-coupled receptor 17 (GPR17), a membrane receptor, negatively regulates oligodendrocyte precursor cell (OPC) differentiation in both developmental and pathological contexts. Nonetheless, GPR17's role in modulating OPC differentiation, facilitating remyelination post SAH, and its interaction with downstream molecules remain elusive. In a rat SAH model induced by arterial puncture, OPCs expressing GPR17 proliferated prominently by day 14 post-onset, coinciding with compromised myelin sheath integrity and cognitive deficits. Selective Gpr17 knockdown in oligodendrocytes (OLs) via adeno-associated virus (AAV) administration revealed that reduced GPR17 levels promoted OPC differentiation, restored myelin sheath integrity, and improved cognitive deficits by day 14 post-SAH. Moreover, GPR17 knockdown attenuated the elevated expression of the inhibitor of DNA binding 2 (ID2) post-SAH, suggesting a GPR17-ID2 regulatory axis. Bi-directional modulation of ID2 expression in OLs using AAV unveiled that elevated ID2 counteracted the restorative effects of GPR17 knockdown. This resulted in hindered differentiation, exacerbated myelin sheath impairment, and worsened cognitive deficits. These findings highlight the pivotal roles of GPR17 and ID2 in governing OPC differentiation and axonal remyelination post-SAH. This study positions GPR17 as a potential therapeutic target for SAH intervention. The interplay between GPR17 and ID2 introduces a novel avenue for ameliorating cognitive deficits post-SAH.

CTA image segmentation method for intracranial aneurysms based on MGLIA net

Accurately segmenting the aneurysm area from CTA data can reconstruct the three-dimensional morphology of the aneurysm, effectively evaluating the type, size, and risk of rupture of the aneurysm. However, accurate separation of the aneurysm is limited by the accuracy of image segmentation algorithms. Currently, the segmentation methods for intracranial aneurysms using CTA big data and deep learning lack universality. When faced with a new hospital acquired imaging modality, it is usually necessary to redesign and train the segmentation network. In response to this issue, this article proposes a more universal segmentation model and develops the GLIA Net algorithm (MGLIA Net model) based on MoblieNet, which can perform adaptive target segmentation on aneurysm images collected under different conditions. To verify the effectiveness of the algorithm in intracranial aneurysm segmentation, performance tests were conducted on an open-source dataset. The results showed that the proposed algorithm achieved segmentation accuracy of 55.9% and 73.1% on two datasets, respectively, significantly better than the original GLIA-Net algorithm.

Robotic thread-assisted clot removal for stroke treatment: A comprehensive review

Stroke is the predominant factor of long-term impairment in developed nations and is a major contributor to death globally. Stroke is a life-threatening neurological condition caused by the occlusion or rupture of blood vessels in the brain. Brain clot restricts blood movement by causing obstruction thus, damaging the blood vessels and tissues, which ultimately causes stroke. Thus, stroke requires immediate and efficient treatment to reduce neurological deterioration and increase patient recuperation. Over the last decade, there have been significant breakthroughs in diagnostic and therapeutic interventionsfor stroke. Stroke is typically treated with immediate therapeutic interventions, which may involve thrombolytic medication infusions like tissue plasminogen activator, anti-coagulants like heparin, or surgical clot clearance procedures like thrombectomy. Despite the significant benefits of these treatments, several disadvantages, including restricted therapeutic index, allergic reactions, and adverse effects (such as hypotension, recurrent stroke, hypoglycaemia, and atypical bleeding), highlight the need for far more innovative solutions. In response to these challenges, a novel approach to treating brain clots has emerged. The study investigates a novel approach to treating strokes caused by brain clots through the utilization of a steerable micro-robotic thread guided by real-time imaging to enhance precision in clot removal. This method addresses the limitations of traditional treatments namely thrombolytics and thrombectomy. In this work, we emphasized the innovative approaches in the removal of brain clots, the use and mechanisms of cutting-edge robotic thread technology, and presented specific case studies demonstrating its application.

Systematic review and meta-analysis of transcranial doppler biomarkers for the prediction of delayed cerebral ischemia following subarachnoid hemorrhage

Delayed cerebral ischemia (DCI) following an aneurysmal subarachnoid hemorrhage (aSAH) significantly impacts mortality, morbidity, and healthcare costs. This study assessed the diagnostic accuracy of Transcranial Doppler (TCD)-derived biomarkers for predicting DCI via a systematic review and meta-analysis. Included studies had to correctly define DCI and report data on sensitivity, specificity, positive predictive value, and negative predictive value. Univariate or bivariate analyses with a random effects model were used, and risk of bias was evaluated with the Quality Assessment of Diagnostic Accuracy Studies. From 23 eligible articles (n = 2371 patients), three biomarker categories were identified: cerebral blood flow velocities (CBFV), cerebral autoregulation, and microembolic signals (MES). The highest sensitivity (0.86, 95% CI 0.71-0.94) and specificity (0.75, 95% CI 0.52-0.94) for DCI prediction were achieved with a mean CBFV of 120 cm/s combined with a Lindegaard ratio. The transient hyperemic response test showed the best performance among autoregulatory biomarkers with a sensitivity of 0.88, (95% CI 0.54-0.98) and specificity of 0.82 (95% CI 0.52-0.94). MES were less effective predictors. Combining CBFV with autoregulatory biomarkers enhanced TCD's predictive value. High heterogeneity and risk of bias were noted, indicating the need for a standardized TCD approach for improved DCI evaluation.

Hereditary Haemorrhagic Cerebrovascular Disease: Implications for Clinical Management

Background

At present, treatment of hereditary haemorrhagic cerebrovascular disease remains in the symptomatic stage. It is more important to provide strategies for developing rational treatment methods, expanding our understanding with regard to the pathophysiology in the context of familial diseases.

Summary

In this article, the combined data from the literature on diseases, including familial cerebral cavernous haemangiomas, hereditary cerebral haemorrhage with amyloidosis, familial intracranial aneurysms, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, were reviewed to manage the haemorrhagic diseases discussed through genetic counselling and early prevention and treatment of these patients and their families, the genetics, pathogenesis, clinical manifestations and treatment.

Key Messages

It is important to understand and treat hereditary haemorrhagic cerebrovascular disease through genetic treatment options.

Investigating the Potential Therapeutic Targeting of the JAK-STAT Pathway in Cerebrovascular Diseases: Opportunities and Challenges

Cerebrovascular disease (CVD) is a significant neurological condition resulting from pathological changes in the brain's blood supply and is currently the leading cause of death and disability worldwide. The progression of CVD is closely associated with endothelial damage, plaque formation, and thrombosis, driven by long-term alterations in vascular endothelial cells, smooth muscle cells, microglia, and other immune-inflammatory cells. Among the key molecular pathways involved, the Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling pathway plays a central role. Dysregulation of the JAK-STAT pathway is implicated in the pathogenesis of CVD by influencing the aforementioned cell types and associated pathological processes. Importantly, the role of the JAK-STAT pathway varies across different types of CVD and throughout different stages of disease progression (e.g., pre-morbid, acute, and chronic phases). This review examines the composition, activation, and regulation of the JAK-STAT pathway and summarizes recent findings on its involvement in CVD. We discuss the distinct roles of JAK-STAT signaling in various CVD conditions, the potential reasons for these differences, and explore the clinical translational prospects and technical challenges of targeting the JAK-STAT pathway for therapeutic intervention in CVD.

Stem Cells Treatment for Subarachnoid Hemorrhage

BACKGROUND

Subarachnoid hemorrhage (SAH) refers to bleeding in the subarachnoid space, which is a serious neurologic emergency. However, the treatment effects of SAH are limited. In recent years, stem cell (SC) therapy has gradually become a very promising therapeutic method and advanced scientific research area for SAH.

REVIEW SUMMARY

The SCs used for SAH treatment are mainly bone marrow mesenchymal stem cells (BMSCs), umbilical cord mesenchymal stem cells (hUC-MSCs), dental pulp stem cells (DPSCs), neural stem cells (NSCs)/neural progenitor cell (NPC), and endothelial progenitor cell (EPC). The mechanisms mainly included differentiation and migration of SCs for tissue repair; alleviating neuronal apoptosis; anti-inflammatory effects; and blood-brain barrier (BBB) protection. The dosage of SCs was generally 10 6 orders of magnitude. The administration methods included intravenous injection, nasal, occipital foramen magnum, and intraventricular administration. The administration time is generally 1 hour after SAH modeling, but it may be as late as 24 hours or 6 days. Existing studies have confirmed the neuroprotective effect of SCs in the treatment of SAH.

CONCLUSIONS

SC has great potential application value in SAH treatment, a few case reports have provided support for this. However, the relevant research is still insufficient and there is still a lack of clinical research on the SC treatment for SAH to further evaluate the effectiveness and safety before it can go from experiment to clinical application.

Influence of meteorological changes on the occurrence of cerebral aneurysm rupture in the Montpellier region: A retrospective study

BACKGROUND/CONTEXT

Aneurysmal subarachnoid hemorrhage (aSAH) is a sudden and potentially serious event. Recognized risk factors of aSAH include smoking, high blood pressure, and alcohol consumption. Some studies have reported associations between risk of aSAH and climatic conditions, but no consensus exists. This study aimed to investigate the association between aSAH and meteorological conditions.

METHODS

We retrospectively included patients admitted for aSAH at Montpellier University Hospital between 2018-2022. We analyzed the correlation between the occurrence of aSAH and several meteorological factors, including precipitation, temperature, barometric pressure, wind speed, humidity, sunshine duration, and storms, within 24 h and 7 days before symptom onset. We collected meteorological data for days without aSAH cases as controls. A multivariate logistic regression with 10-block cross-validation and a penalty lasso method was performed.

RESULTS

For the 5-year period, 492 patients were analyzed. Incident cases per month in this period was higher in February and August and the highest in winter. Diagnoses were made predominantly between noon and midnight. The multivariate model based on 9 weather variables on the days preceding the aSAH event had an accuracy of 0.55. The area under the curve was 0.58 (95% CI 0.55-0.62). The barometric pressure was similar between aSAH days and the mean of the 5 preceding days.

CONCLUSION

Due to the low accuracy of the statistical model, our study could not provide evidence of a link between weather variables and occurrence of aSAH. This issue requires further investigation and reliable epidemiological data to fully understand the pathophysiology and real impact of weather on aSAH.

Evidence-Based Approach to Cerebral Vasospasm and Delayed Cerebral Ischemia: Milrinone as a Therapeutic Option-A Narrative Literature Review and Algorithm Treatment Proposition

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe neurocritical condition often complicated by cerebral vasospasm (CVS), leading to delayed cerebral ischemia (DCI) and significant morbidity and mortality. Despite advancements in management, therapeutic options with robust evidence remain limited. Milrinone, a phosphodiesterase type 3 (PDE3) inhibitor, has emerged as a potential therapeutic option. Intravenous milrinone demonstrated clinical and angiographic improvement in 67% of patients, reducing the need for mechanical angioplasty and the risk of functional disability at 6 months (mRS ≤ 2). Side effects, including hypotension, tachycardia, and electrolyte disturbances, were observed in 33% of patients, occasionally leading to early drug discontinuation. Based on the evidence, we propose a treatment algorithm for using milrinone to optimize outcomes and standardize its application in neurocritical care settings.

Comparison of prediction for short-term and long-term outcomes in patients with aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

Despite extensive research on prediction models for outcomes in aneurysmal subarachnoid hemorrhage (aSAH) patients, the distinction between models for short- and long-term outcomes remains insufficiently explored. This study aims to compare these models, identify the risk factors of poor outcomes, summarize the predictors of outcomes, and assess the performance of the prediction models for short- and long-term outcomes in aSAH patients. PubMed, Web of Science, the Cochrane Library, and Embase were searched to identify studies investigating risk factors for developed and/or validated prediction models for short-term (< 12 months) and long-term (≥ 12 months) outcomes in aSAH patients. The main outcome was neurological function, defined as poor if the Glasgow Outcome Scale (GOS) score was ≤ 3, or if the modified Rankin Scale (mRS) score was ≥ 3. Fifty-six studies reporting 61 models with 36,879 aSAH patients were included. A total of 93 predictors were examined and categorized into six domains including demographic factors, scoring systems, clinical factors, aneurysm characteristics, laboratory examinations, and imaging features. Among these, laboratory examinations were included in 57.45% (27/47) of models predicting short-term outcomes, while only 14.29% (2/14) of long-term prediction models incorporated them. An mFisher score of 3-4 [OR = 1.95, 95%CI (1.43, 2.64), P < 0.01] and the presence of multiple aneurysms [OR = 1.56, 95% CI (1.25, 1.94), P < 0.01] were identified as risk factors for poor short-term outcomes, however, this association was weakened in predicting poor long-term outcomes. All studies were found to have a high risk of bias, primarily due to inappropriate data sources and inadequate reporting of the analysis domain. This review suggested that aSAH patients with poor clinical scores and hypertension are at a higher risk of poor outcomes. The majority of the included prediction models perform well, but generally lack reporting in the analysis domain, which may hinder their clinical applicability.

Preventive effect of aminocaproic acid combined with nimodipine on short-term rebleeding in patients with aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening and life-limiting disease with high mortality and disability rates. Herein, we aim to explore the preventive effect of aminocaproic acid combined with nimodipine on short-term rebleeding in patients with aSAH. Retrospectively, the medical data of patients with aSAH ( n  = 256) were collected. According to different treatment methods, patients were categorized into the aminocaproic acid + nimodipine group ( n  = 152) and the nimodipine group ( n  = 104), and were treated for 1 week. Baseline characteristics, incidence of rebleeding, average velocity of cerebral artery blood flow, cerebral vasospasm index, vascular endothelial function, complications, and adverse events were analyzed between the two groups. After 1-week treatment, compared to the nimodipine group, the aminocaproic acid + nimodipine group exhibited lower incidence of rebleeding, notable decreases in average velocity of cerebral artery blood flow and the cerebral vasospasm index, and downregulation of endothelin-1 and vascular endothelial growth factor ( P  < 0.05). There were no significant differences about complications and adverse events between the two groups. Aminocaproic acid combined with nimodipine is superior to nimodipine alone in preventing the short-term rebleeding in patients with aSAH, and has good safety.

Clinical Application of Ventricular Intracranial Pressure Monitoring in the Treatment of Ruptured Anterior Circulation Aneurysms: A Retrospective Study

OBJECTIVE

To evaluate the clinical effectiveness of ventricular intracranial pressure (ICP) monitoring in the treatment of ruptured anterior circulation aneurysms and to explore its impact on intracranial pressure control, postoperative complications, length of hospital stay, and neurological recovery.  Methods: A retrospective analysis was conducted on 67 patients who underwent surgical clipping for ruptured anterior circulation aneurysms at Jinjiang Hospital, Fujian Province, between January 2021 and June 2024. The patients were divided into an experimental group (32 patients) and a control group (35 patients). Clinical characteristics, operation time, intraoperative blood loss, postoperative changes in ICP, postoperative complications, length of hospital stay, and neurological recovery were compared between the two groups.  Results: No significant differences were found between the experimental and control groups in terms of clinical characteristics, operation time, or intraoperative blood loss (P > 0.05). However, the experimental group showed superior outcomes compared to the control group in postoperative ICP changes, simplified early brain edema score (SEBES) at 72 hours, length of hospital stay, and Glasgow Outcome Scale (GOS) scores at discharge, with statistically significant differences (P < 0.05).  Conclusion: Ventricular ICP monitoring during the surgical clipping of ruptured anterior circulation aneurysms is an effective method for controlling intracranial pressure, reducing postoperative complications, shortening the length of hospital stay, and promoting neurological recovery. This approach offers a safer and more efficient monitoring solution with promising clinical applicability.

Pharmacological inhibition of P2RX4 receptor as a potential therapeutic strategy to prevent intracranial aneurysm formation

Intracranial aneurysms (IA) affect 1-5 % of the population and are a major cause of subarachnoid hemorrhage. Thus, preventing IA development and progression is crucial for public health. IA has been considered a non-physiological, high shear stress-induced chronic inflammatory disease affecting the bifurcation site of the intracranial arteries. Therefore, factors that sense high shear stress and induce IAs by triggering inflammation could potentially act as therapeutic targets. P2RX4 is a member of the purinoreceptor family that converts the strength of shear stress into intracellular signals. To verify its therapeutic potential, we investigated the effects of P2RX4 and a selective antagonist on the formation of IAs. Results showed that P2RX4 deficiency significantly suppressed the formation of IAs. Consistently, the selective P2RX4 antagonist NC-2600, which potently inhibited Ca2+ influx in response to shear-stress loading in endothelial cells in vitro, significantly suppressed the formation of IAs. The results of the present study contribute to our understanding of the pathogenesis of IAs and may provide benefits to society through the future development of medical therapies targeting P2RX4.

Clinical Characteristics and Outcomes in Patients with Ruptured Middle Cerebral Artery Aneurysms: A Multicenter Study in Northern China

INTRODUCTION

The long-term prognosis of ruptured middle cerebral artery aneurysms (MCAAs) in northern China remains unclear. The aim of this study is to analyze the epidemiological characteristics and long-term outcomes of ruptured MCAAs in northern China.

METHODS

We included patients who were consecutively admitted for ruptured MCAAs to 12 tertiary care centers in northern China from January 2017 to December 2020. Kaplan‒Meier curves were used to compare survival in hazard strata. The Cox proportional hazards model was used to analyze risk factors and mortality risk, whereas logistic regression was used to identify factors influencing 2-year survival. Subgroup analyses were performed to verify the robustness of the results.

RESULTS

Data on 959 patients with ruptured MCAAs were analyzed; 16.4% of these patients had ruptured intracranial aneurysms (RIAs) and were registered in the Chinese cerebral aneurysm database. The mean follow-up duration was 3.0 years (range 0-6.2 years). The 3-month and 2-year mortality rates were 15.5% and 18.2%, respectively. The risk factors for mortality were identified via Cox regression and were as follows: age > 70 years, previous stroke, combined intracerebral hemorrhage (ICH)/intraventricular hemorrhage (IVH), poor Hunt and Hess grade, multiple aneurysms, and conservative treatment (CT). The positive association between the risk of death and CT was consistent across subgroups. According to logistic regression, hypertension, previous stroke, combined ICH/IVH, Hunt and Hess grade, and WFNS (World Federation of Neurological Surgeons) score were identified as factors negatively influencing 2-year survival.

CONCLUSION

We detail the epidemiologic characteristics and long-term outcomes of MCAAs. The risk factors for mortality included age > 70 years, previous stroke, combined ICH/IVH, poor Hunt and Hess grade, and multiple aneurysms. Compared with microsurgical treatment (MST), CT is associated with an increased risk of mortality, while the risk of mortality associated with endovascular treatment (EVT) is not significantly different. Two-year survival was associated with hypertension, previous stroke, ICH/IVH, and poor grades at admission.

Risk Score for Early Prediction of In-Hospital Mortality After Aneurysmal Subarachnoid Hemorrhage: Pooled Analysis With Score Construction and Validation

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) has a high complications burden, with in-hospital mortality as the most devastating outcome. We aimed to develop and validate a risk score for early prediction of in-hospital mortality after aSAH.

METHODS

Data from 2 university hospitals were pooled (n = 1070), with cohorts for score construction (n = 886) and external validation (n = 184). Several parameters assessable at admission were collected. Independent predictors of in-hospital mortality were used as mortality score components. Diagnostic accuracy of the novel score was compared to the Hunt and Hess Age, Intraventricular Hemorrhage, Rebleed and World Federation of Neurosurgical Societies (WFNS) scores.

RESULTS

Overall rate of in-hospital mortality was 19% and 14.7% in construction and validation cohorts, respectively. The novel risk score (aSAH mortality score: 0-12 points) included patients' age (≤55 years: 0 points, 56-70 years: 1 point, >70 years: 2 points), aneurysm rebleeding (2 points), WFNS grade (grade I-II: 0 points, grade III-IV: 2 points, grade V: 5 points), and Hijdra sum score (≤10: 0 points, 11-20: 1 point, 21-30: 2 points, >30: 3 points). In-hospital mortality rates ranged 0.6% (0 points) to 100% (12 points) in the construction cohort, and 0% (0 points) to 60% (10 points) in the validation cohort. In the receiver operating characteristic analysis, the aneurysmal subarachnoid hemorrhage mortality score (area under the curve [AUC]: 0.829 and 0.824 in the construction and validation cohorts, respectively) was superior to the Hunt and Hess Age, Intraventricular Hemorrhage, Rebleed (AUC: 0.811 and 0.813) and WFNS scores (AUC: 0.768 and 0.795).

CONCLUSIONS

Risk of in-hospital mortality after aSAH can be predicted with high accuracy using baseline characteristics. The novel risk score showed best diagnostic performance in the construction and validation cohorts and can aid in early prognostication and treatment decisions.

Regulatory T Cell- and Natural Killer Cell-Mediated Inflammation, Cerebral Vasospasm, and Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage-A Systematic Review and Meta-Analysis Approach

Aneurysmal subarachnoid hemorrhage (SAH) involves a significant influx of blood into the cerebrospinal fluid, representing a severe form of stroke. Despite advancements in aneurysm closure and neuro-intensive care, outcomes remain impaired due to cerebral vasospasm and delayed cerebral ischemia (DCI). Previous pharmacological therapies have not successfully reduced DCI while improving overall outcomes. As a result, significant efforts are underway to better understand the cellular and molecular mechanisms involved. This review focuses on the activation and effects of immune cells after SAH and their interactions with neurotoxic and vasoactive substances as well as inflammatory mediators. Particular attention is given to clinical studies highlighting the roles of natural killer (NK) cells and regulatory T cells (Treg) cells. Alongside microglia, astrocytes, and oligodendrocytes, NK cells and Treg cells are key contributors to the inflammatory cascade following SAH. Their involvement in modulating the neuro-inflammatory response, vasospasm, and DCI underscores their potential as therapeutic targets and prognostic markers in the post-SAH recovery process. We conducted a systematic review on T cell- and natural killer cell-mediated inflammation and their roles in cerebral vasospasm and delayed cerebral ischemia. We conducted a meta-analysis to evaluate outcomes and mortality in studies focused on NK cell- and T cell-mediated mechanisms.

Stress hyperglycemia ratio is associated with delayed cerebrovascular ischemia and poor prognosis in patients with aneurysmal subarachnoid hemorrhage undergoing neurointerventional therapy

OBJECTIVE

Previous research has established a correlation between hyperglycemia following aneurysmal subarachnoid hemorrhage (aSAH) and the onset of delayed cerebrovascular ischemia (DCI), and influencing patient prognosis. The objective of this study was to evaluate the potential association between stress hyperglycemia ratio (SHR) and both the occurrence of DCI and prognosis in patients with aSAH undergoing neurointervention.

METHODS

We retrospectively analyzed 214 patients with aSAH undergoing neurointervention. The outcomes evaluated were DCI and 90-days poor prognosis (Modified Rankin Scale, mRS >2). The association between SHR level and both DCI and prognosis was analyzed. Stress hyperglycemia was assessed using SHR, calculated as: SHR = admission fasting plasma glucose (FPG, mmol/L) / [1.59 * hemoglobin A1c (HbA1c%) - 2.59].

RESULTS

Among the 214 patients, 59 (27.6 %) experienced DCI, and 60 (28 %) had a poor prognosis. Following adjustments for confounding factors, SHR emerged as an independent risk factor of both DCI (p = 0.006) and poor prognosis (p = 0.020), individuals in the T3 tertile of SHR had a higher risk of DCI than those in the T1 tertile [odds ratio (OR) 2.68; 95 % CI (1.19-6.06); p = 0.018], and individuals in the T3 tertile of SHR had a higher risk of poor 90-day prognosis than those in the T1 tertile [OR 2.47; 95 % CI (1.08-5.63); p = 0.032].

CONCLUSION

SHR was found to be a significant and independent risk factor for DCI and 90-days poor prognosis in patients with aSAH who underwent neurointerventional therapy.

Systematic Mendelian Randomization Exploring Druggable Genes for Hemorrhagic Strokes

Patients with hemorrhagic stroke have high rates of morbidity and mortality, and drugs for prevention are very limited. Mendelian randomization (MR) analysis can increase the success rate of drug development by providing genetic evidence. Previous MR analyses only analyzed the role of individual drug target genes in hemorrhagic stroke; therefore, we used MR analysis to systematically explore the druggable genes for hemorrhagic stroke. We sequentially performed summary-data-based MR analysis and two-sample MR analysis to assess the associations of all genes within the database with intracranial aneurysm, intracerebral hemorrhage, and their subtypes. Validated genes were further analyzed by colocalization. Only genes that were positive in all three analyses and were druggable were considered desirable genes. We also explored the mediators of genes affecting hemorrhagic stroke incidence. Finally, the associations of druggable genes with other cardiovascular diseases were analyzed to assess potential side effects. We identified 56 genes that significantly affected hemorrhagic stroke incidence. Moreover, TNFSF12, SLC22A4, SPARC, KL, RELT, and ADORA3 were found to be druggable. The inhibition of TNFSF12, SLC22A4, and SPARC can reduce the risk of intracranial aneurysm, subarachnoid hemorrhage, and intracerebral hemorrhage. Gene-induced hypertension may be a potential mechanism by which these genes cause hemorrhagic stroke. We also found that blocking these genes may cause side effects, such as ischemic stroke and its subtypes. Our study revealed that six druggable genes were associated with hemorrhagic stroke, and the inhibition of TNFSF12, SLC22A4, and SPARC had preventive effects against hemorrhagic strokes.

Dental Pulp Stem Cells Attenuate Early Brain Injury After Subarachnoid Hemorrhage via miR-26a-5p/PTEN/AKT Pathway

Subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke with high morbidity, mortality and disability, and early brain injury (EBI) after SAH is crucial for prognosis. Recently, stem cell therapy has garnered significant attention in the treatment of neurological diseases. Compared to other stem cells, dental pulp stem cells (DPSCs) possess several advantages, including abundant sources, absence of ethical concerns, non-invasive procurement, non-tumorigenic history and neuroprotective potential. Therefore, we aim to investigate whether DPSCs can improve EBI after SAH, and explore the mechanisms. In our study, we utilized the endovascular perforation method to establish a SAH mouse model and investigated whether DPSCs administered via tail vein injection could improve EBI after SAH. Furthermore, we used hemin-stimulated HT22 cells to simulate neuronal cell injury induced by SAH and employed a co-culture approach to examine the effects of DPSCs on these cells. To gain insights into the potential mechanisms underlying the improvement of SAH-induced EBI by DPSCs, we conducted bioinformatics analysis. Finally, we further validated our findings through experiments. In vivo experiments, we found that DPSCs administration improved neurological dysfunction, reduced brain edema, and prevented neuronal apoptosis in SAH mice. Additionally, we observed a decrease in the expression level of miR-26a-5p in the cortical tissues of SAH mice, which was significantly increased following intravenous injection of DPSCs. Through bioinformatic analysis and luciferase reporter assay, we confirmed the target relationship between miR-26a-5p and PTEN. Moreover, we demonstrated that DPSCs exerted neuroprotective effects by modulating the miR-26a-5p/PTEN/AKT pathway. Our study demonstrates that DPSCs can improve EBI after SAH through the miR-26a-5p/PTEN/AKT pathway, laying a foundation for the application of DPSCs in SAH treatment. These findings provide a theoretical basis for further investigating the therapeutic mechanisms of DPSCs and developing novel treatment strategies in SAH.

Skull bone marrow and skull meninges channels: redefining the landscape of central nervous system immune surveillance

The understanding of neuroimmune function has evolved from concepts of immune privilege and protection to a new stage of immune interaction. The discovery of skull meninges channels (SMCs) has opened new avenues for understanding central nervous system (CNS) immunity. Here, we characterize skull bone marrow and SMCs by detailing the anatomical structures adjacent to the skull, the differences between skull and peripheral bone marrow, mainstream animal processing methods, and the role of skull bone marrow in monitoring various CNS diseases. Additionally, we highlight several unresolved issues based on current research findings, aiming to guide future research directions.

The role of the neurovascular unit in vascular cognitive impairment: Current evidence and future perspectives

Vascular cognitive impairment (VCI) is a progressive cognitive impairment caused by cerebrovascular disease or vascular risk factors. It is the second most common type of cognitive impairment after Alzheimer's disease. The pathogenesis of VCI is complex, and neurovascular unit destruction is one of its important mechanisms. The neurovascular unit (NVU) is responsible for combining blood flow with brain activity and includes endothelial cells, pericytes, astrocytes and many regulatory nerve terminals. The concept of an NVU emphasizes that interactions between different types of cells are essential for maintaining brain homeostasis. A stable NVU is the basis of normal brain function. Therefore, understanding the structure and function of the neurovascular unit and its role in VCI development is crucial for gaining insights into its pathogenesis. This article reviews the structure and function of the neurovascular unit and its contribution to VCI, providing valuable information for early diagnosis and prevention.

Hyperoxia and unfavourable outcome in patients with non-traumatic subarachnoid haemorrhage: A systematic review and meta-analysis

BACKGROUND

It is common practice to administer oxygen to neurocritical patients in the Intensive Care Unit (ICU). Consequent hyperoxia has been associated with unfavourable outcomes including in patients with brain injury, after cardiac arrest, sepsis, and traumatic brain injury. The aim of this systematic review was to explore the association between hyperoxia exposure and unfavourable outcome in patients following a non-traumatic subarachnoid haemorrhage (SAH).

METHODS

Systematic searches of Medline, Embase, Emcare, CINAHL and PubMed were performed in February 2024 using key words for SAH and hyperoxia. Non-human studies, articles in languages other than English, studies that did not measure blood oxygenation levels via pulse oximetry or arterial blood gas analyses, and studies exploring traumatic SAH were excluded. The Newcastle-Ottawa Risk of Bias tool (NOS) was used to assess the quality of included manuscripts. The primary outcome was a composite outcome combining mortality or poor functional neurological outcome. Secondary outcomes included mortality, poor functional neurological outcome, and development of delayed cerebral ischaemia (DCI).

RESULTS

The literature search yielded 1,219 non-duplicate articles published after 1 January 2000, of which 21 articles were reviewed as full-texts and nine were included in this review. All included studies were rated good/high quality using the NOS. Hyperoxia exposure was associated with increased risk of adverse composite outcome of death or unfavourable functional neurological outcome (odds ratio (OR) 1.61, 95% confidence interval (CI) 1.19-2.16), poor functional neurological outcome alone (OR 1.79, 95% CI 1.33-2.42) and development of DCI (OR 2.63, 95% CI 1.79-3.85). The association of hyperoxia and hospital mortality alone was not statistically significant (OR 1.42, 95% CI 0.98-2.04).

CONCLUSION

Hyperoxia may contribute to unfavourable outcomes and the development of DCI after an non-traumatic SAH. Trials using restrictive oxygen therapy among patients with SAH are indicated.

Clinical development of the GluN2B-selective NMDA receptor inhibitor NP10679 for the treatment of neurologic deficit after subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) may be associated with cerebral vasospasm, which can lead to delayed cerebral ischemia, infarction, and worsened functional outcomes. The delayed nature of cerebral ischemia secondary to SAH-related vasculopathy presents a window of opportunity for the evaluation of well tolerated neuroprotective agents administered soon after ictus. Secondary ischemic injury in SAH is associated with increased extracellular glutamate, which can overactivate N-methyl-d-aspartate receptors (NMDARs), thereby triggering NMDAR-mediated cellular damage. In this study, we evaluated the effect of the pH-sensitive GluN2B-selective NMDAR inhibitor NP10679 on neurologic impairment after SAH. This compound demonstrates a selective increase in potency at the acidic extracellular pH levels that occur in the setting of ischemia. We found that NP10679 produced durable improvement of behavioral deficits in a well characterized murine model of SAH, and these effects were greater than those produced by nimodipine alone, the current standard of care. In addition, we observed an unexpected reduction in SAH-induced luminal narrowing of the middle cerebral artery. Neither nimodipine nor NP10679 alters each other's pharmacokinetic profile, suggesting no obvious drug-drug interactions. Based on allometric scaling of both toxicological and efficacy data, the therapeutic margin in humans should be at least 2. These results further demonstrate the utility of pH-dependent neuroprotective agents and GluN2B-selective NMDAR inhibitors as potential therapeutic strategies for the treatment of aneurysmal SAH. SIGNIFICANCE STATEMENT: This report describes the properties and utility of the GluN2B-selective pH-sensitive N-methyl-d-aspartate receptor inhibitor, NP10679, in a well characterized rodent model of subarachnoid hemorrhage. We show that the administration of NP10679 improves long-term neurological function following subarachnoid hemorrhage and that in rats, there are no drug-drug interactions between NP10679 and nimodipine, the standard of care for this indication.

Multifaceted role of thrombin in subarachnoid hemorrhage: Focusing on cerebrospinal fluid circulation disorder

Subarachnoid hemorrhage (SAH) is a severe neurological condition characterized by high morbidity and mortality. The unfavorable prognosis of SAH is closely associated with early brain injury (EBI) and delayed cerebral ischemia (DCI), wherein thrombin plays a role as part of the secondary injury components following hemorrhage in these two pathological processes. Additionally, thrombin contributes to disruptions in the circulation of cerebrospinal fluid (CSF), thereby giving rise to a spectrum of sequelae following SAH, including cerebral edema, hydrocephalus, cognitive impairments, and depressive symptoms. This review aims to provide a comprehensive understanding of the pathological role of thrombin in EBI, DCI, and CSF circulation following SAH, with a specific focus on its impact on the glymphatic-meningeal lymphatic system-a crucial mechanism for waste clearance and neurohomeostatic regulation. Additionally, this review offers an overview of current pharmacological interventions and treatment modalities targeting pathogenic mechanisms, aiming to mitigate brain injury and promote neurological recovery post-SAH.

Comprehensive Management of Intracranial Aneurysms Using Artificial Intelligence: An Overview

Intracranial aneurysms (IAs), an asymptomatic vascular lesion, are becoming increasingly common as imaging technology progresses. Subarachnoid hemorrhage from IAs rupture entails a substantial risk of mortality or severe disability. The early detection and prompt intervention of IAs posing a high risk of rupture are paramount for optimizing clinical management and safeguarding patients' lives. Artificial intelligence (AI), with its exceptional capabilities in image-based tasks, has garnered significant scholarly interest worldwide. Its application in the management of IAs holds promise for advancing medical research and patient care. Utilizing deep learning algorithms, AI exhibits remarkable capabilities in precisely identifying and segmenting aneurysms, significantly enhancing diagnostic sensitivity and accuracy. Furthermore, AI can meticulously analyze extensive aneurysm datasets to forecast aneurysm growth, rupture hazards, and prognostic scenarios, offering clinician's invaluable assistance in decision-making. This article comprehensively examines the latest advancements in the utilization of AI in aneurysm treatment, encompassing detection and segmentation, rupture risk assessment, prediction of therapeutic outcomes, and facilitation of microcatheter shaping. A brief discussion is held on the challenges and future paths for clinical AI deployments.

Value of vendor-agnostic deep learning image denoising in brain computed tomography: A multi-scanner study

To evaluate the effect of a vendor-agnostic deep learning denoising (DLD) algorithm on diagnostic image quality of non-contrast cranial computed tomography (ncCT) across five CT scanners.This retrospective single-center study included ncCT data of 150 consecutive patients (30 for each of the five scanners) who had undergone routine imaging after minor head trauma. The images were reconstructed using filtered back projection (FBP) and a vendor-agnostic DLD method. Using a 4-point Likert scale, three readers performed a subjective evaluation assessing the following quality criteria: overall diagnostic image quality, image noise, gray matter-white matter differentiation (GM-WM), artifacts, sharpness, and diagnostic confidence. Objective analysis included evaluation of noise, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and an artifact index for the posterior fossa.In subjective image quality assessment, DLD showed constantly superior results compared to FBP in all categories and for all scanners (p<0.05) across all readers. The objective image quality analysis showed significant improvement in noise, SNR, and CNR as well as for the artifact index using DLD for all scanners (p<0.001).The vendor-agnostic deep learning denoising algorithm provided significantly superior results in the subjective as well as in the objective analysis of ncCT images of patients with minor head trauma concerning all parameters compared to the FBP reconstruction. This effect has been observed in all five included scanners. · Significant improvement of image quality for 5 scanners due to the vendor-agnostic DLD. · Subjects were patients with routine imaging after minor head trauma. · Reduction of artifacts in the posterior fossa due to the DLD. · Access to improved image quality even for older scanners from different vendors. · Kapper C, Müller L, Kronfeld A et al. Value of vendor-agnostic deep learning image denoising in brain computed tomography: A multi-scanner study. Fortschr Röntgenstr 2024; DOI 10.1055/a-2290-4781.

Asiatic acid alleviates subarachnoid hemorrhage-induced brain injury in rats by inhibiting ferroptosis of neurons via targeting acyl-coenzyme a oxidase 1

The occurrence of subarachnoid hemorrhage (SAH) can lead to brain injury, which is a fatal condition with limited effective clinical intervention strategies. The naturally occurring component Asiatic acid (AA), found in the tropical plant Centella asiatica, has been reported to possess neuroprotective properties. The objective of this study was to evaluate the neuroprotective effect of AA following SAH and investigate its potential mechanisms. The SAH model was established in male Sprague-Dawley (SD) rats through intravascular perforation, following a standardized protocol. The administration of AA was performed via gavage following SAH. A lentiviral vector was constructed and utilized for the knockdown of Acyl Coenzyme A Oxidase 1 (ACOX1) Firstly, AA treatment effectively improves brain neurological deficit, neuronal damage, and iron deposition induced by SAH. Furthermore, it has been demonstrated that AA directly interacts with ACOX1, which exhibits decreased expression in neurons following SAH. Additionally, our study reveals AA can reverse SAH-induced reduction in ACOX1 expression, concurrently ameliorating neuronal ferroptosis. This improvement is evidenced by reduced lipid peroxidation, including mitigated GSH depletion, decreased MDA production, and increased GPX4 content and activity. Also, AA enhances mitochondrial constriction while alleviating cristae disruption induced by SAH, providing crucial insights into its neuroprotective effects against neuronal ferroptosis in SAH. Moreover, when ACOX1 is knocked down, the neuroprotective effects of AA are weakened. Collectively, this study elucidated the neuroprotective effect of AA by inhibiting neuronal cell ferroptosis through targeting ACOX1. These findings suggest that AA holds promise as a potential therapeutic candidate for ameliorating SAH-induced brain injury.

Risk Factors for the Development of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is a common neurosurgical disorder with high morbidity and poor prognosis, and the associated delayed cerebral ischemia (DCI) is a key factor contributing to poor prognosis. Despite extensive research on the risk factors associated with DCI development, the evidence remains conflicting. Therefore, this meta-analysis of case-control studies aimed to investigate the risk factors for DCI occurrence during hospitalization in patients with aSAH.

METHODS

We systematically searched PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials for eligible studies published before November 20, 2023. Two independent reviewers extracted relevant data from the included studies using a pre-established data extraction form. The primary outcome was DCI occurrence during hospitalization in patients with aSAH.

RESULTS

A total of 42 studies involving 21,726 patients with aSAH were included. The pooled meta-analysis showed that female sex; Hunt-Hess, modified Fisher, and World Federation of Neurosurgical Societies scale scores of 4-5, 3-4, and 4-5, respectively; vasospasm; combined intraventricular hemorrhage; pre-existing hypertension; hydrocephalus; intracranial infections; and high white blood cell count on admission were independent risk factors for the development of postoperative DCIs in patients with aSAH.

CONCLUSIONS

Patients with aSAH who have a Hunt-Hess scale score ≥4, a modified Fisher scale score ≥3, a WFNS scale score ≥4, intraventricular hemorrhage, pre-existing hypertension, cerebral vasospasm, a high white blood cell count on admission, intracranial infection, and female sex are at high risk of DCI and hence should be carefully monitored in the intensive care unit.

Progressive histological and behavioral deterioration of a novel mouse model of secondary hydrocephalus after subarachnoid hemorrhage

Hydrocephalus commonly occurs after subarachnoid hemorrhage (SAH) and is associated with increased morbidity and disability in patients with SAH. Choroid plexus cerebrospinal fluid (CSF) hypersecretion, obliterative arachnoiditis occluding the arachnoid villi, lymphatic obstruction, subarachnoid fibrosis, and glymphatic system injury are considered the main pathological mechanisms of hydrocephalus after SAH. Although the mechanisms of hydrocephalus after SAH are increasingly being revealed, the clinical prognosis of SAH still has not improved significantly. Further research on SAH is needed to reveal the underlying mechanisms of hydrocephalus and develop translatable therapies. A model that can stably mimic the histopathological and neuroethological features of hydrocephalus is critical for animal experiments. There have been fewer animal studies on hydrocephalus after SAH than on other stroke subtypes. The development of a reproducible and effective model of hydrocephalus after SAH is essential. In this study, we establish a mouse model of SAH that stably mimics brain injury and hydrocephalus after SAH through injections of autologous blood into the cisterna magna via different methods and characterize the model in terms of neurological behavior, histology, imaging, neuronal damage, and white matter damage.

SIRT2 Promotes NLRP3-Mediated Microglia Pyroptosis and Neuroinflammation via FOXO3a Pathway After Subarachnoid Hemorrhage

Purpose

This study primarily elucidating the specific mechanism of SIRT2 on neuroinflammation and microglial pyroptosis in a mouse model of SAH.

Patients and Methods

CSF were collected from 57 SAH patients and 11 healthy individuals. C57BL/6 mouse SAH model was established using prechiasmatic cistern blood injection and the in vitro hemoglobin (Hb) stimulation microglia model. Lentivirus was used as a vector for RNA interference technology to knock down the SIRT2 gene expression. Small interfering RNA was used to knockdown the expression of FOXO3a. The tools included measurements of brain water content, neurological scores, Western blot, PCR, ELISA, TEM, immunofluorescence, LDH assay, modified Garcia score, and balance beam tests to evaluate changes in pyroptosis and neuroinflammatory responses.

Results

In CSF samples from SAH patients, elevated levels of SIRT2 and GSDMD were observed, with SIRT2 demonstrating particular diagnostic value for predicting prognosis at the 3-month follow-up. SIRT2 upregulation exacerbated neurological deficits, brain edema, and blood-brain barrier disruption in mice following SAH. SIRT2 increased GSDMD, caspase-1, and IL-1β/IL-18 expression, and amplified GSDMD-positive microglia. FOXO3a was also upregulated post-SAH. siRNA-mediated SIRT2 knockdown ameliorated microglial pyroptosis after SAH. FOXO3a siRNA reduced NLRP3 inflammasome activation and microglial pyroptosis severity, along with neuroinflammation post-SAH.

Conclusion

In summary, SIRT2 promoted microglial pyroptosis, primarily by increasing the expression and activity of Foxo3a, thereby exacerbating neuroinflammatory damage following subarachnoid hemorrhage.

Update on Strategies to Reduce Early Brain Injury after Subarachnoid Hemorrhage

PURPOSE OF REVIEW

Early brain injury (EBI) after aneurysmal subarachnoid hemorrhage (SAH) is the most influential clinical determinant of outcomes. Despite significant advances in understanding of the pathophysiology of EBI, currently no treatments to target EBI have been developed. This review summarizes recent advances in EBI research over the past five years with a focus on potential therapeutic targets.

RECENT FINDINGS

Mechanism-specific translational studies are converging on several pathophysiologic pathways: improved antioxidant delivery and the Sirt1/Nrf2 pathway for reactive oxygen species; NLRP3 inflammasome and microglial polarization for inflammation; and the PI3K/Akt pathway for apoptosis. Recently identified mechanistic components, such as microcirculatory failure and ferroptosis, need particular attention. Clinical studies developing radiographic markers and mechanism-specific, biofluid markers are attempting to bridge the translational therapeutic gap. There has been an exponential growth in EBI research. Further clinical studies which address specific pathophysiology mechanisms need to be performed to identify novel therapeutic approaches.

Enlarged Perivascular Spaces (EPVS) Associated with Functional and Cognitive Outcome After Aneurysm Subarachnoid Hemorrhage (aSAH)

Aneurysmal rupture is the main cause of subarachnoid hemorrhage (SAH), leading to neurological and cognitive deficits. The clinical significance of enlarged perivascular spaces (EPVS) on aSAH (aneurysm subarachnoid hemorrhage) outcomes was unclear. Our aim was to explore the association between EPVS and the clinical outcomes of aSAH. Magnetic resonance imaging (MRI) scans of 195 aSAH survivors were analyzed. Poor outcome was defined as modified Rankin Scale (mRS) ≥ 3. Cognitive outcomes were measured with the Montreal Cognitive Assessment (MoCA). We compared the clinical characteristics of aSAH with EPVS < 10 and EPVS ≥ 10 in basal ganglia (BG) and centrum semiovale (CSO) and investigated the association of EPVS severity and topography with delayed cerebral ischemia (DCI), subacute hydrocephalus, and 3-month unfavorable functional outcome and cognitive status using binary logistic regression model, respectively. At 3 months, 159 patients completed the MoCA assessments, and 63 (39.6%) were diagnosed with cognitive impairment (MoCA < 22). BG-EPVS ≥ 10 was associated with unfavorable functional outcomes at 3 months (odds ratio [OR] 2.426, 95% confidence interval [CI] 1.128-5.216, p < 0.05), subacute hydrocephalus (OR 3.789, 95% CI 1.049-13.093, p < 0.05), and DCI (OR 2.579, 95% CI 1.086-6.123, p < 0.05), but not with cognitive impairment after adjusting for established predictors. CSO-EPVS was linked to unfavorable functional outcomes at 3 months (OR 3.411, 95% CI 1.422-8.195, p < 0.05) and worse cognitive function (OR 2.520, 95% CI 1.136-5.589, p < 0.05). Our cohort study reveals that both BG-EPVS and CSO-EPVS are independently associated with unfavorable functional outcomes after aSAH. However, only CSO-EPVS, not BG-EPVS, is related to cognitive impairment at 3 months.