Early cellular events in the penumbra of human spontaneous intracerebral hemorrhage

A comprehensive prediction model predicts perihematomal edema growth in the acute stage after intracerebral hemorrhage

BACKGROUND

Perihematomal edema (PHE) is regarded as a potential intervention indicator of secondary injury following intracerebral hemorrhage (ICH). But it still lacks a comprehensive prediction model for early PHE formation.

METHODS

The included ICH patients have received an initial Computed Tomography scan within 6 hours of symptom onset. Hematoma volume and PHE volume were computed using semiautomated computer-assisted software. The volume of the hematoma, edema around the hematoma, and surface area of the hematoma were calculated. The platelet-to-lymphocyte ratio (PLR) was calculated by dividing the platelet count by the lymphocyte cell count. All analyses were 2-tailed, and the significance level was determined by P <0.05.

RESULTS

A total of 226 patients were included in the final analysis. The optimal cut-off values for PHE volume increase to predict poor outcomes were determined as 5.5 mL. For clinical applicability, we identified a value of 5.5 mL as the optimal threshold for early PHE growth. In the multivariate logistic regression analyses, we finally found that baseline hematoma surface area (p < 0.001), expansion-prone hematoma (p < 0.001), and PLR (p = 0.033) could independently predict PHE growth. The comprehensive prediction model demonstrated good performance in predicting PHE growth, with an area under the curve of 0.841, sensitivity of 0.807, and specificity of 0.732.

CONCLUSION

In this study, we found that baseline hematoma surface area, expansion-prone hematoma, and PLR were independently associated with PHE growth. Additionally, a risk nomogram model was established to predict the PHE growth in patients with ICH.

Intraventricular Hemorrhage Score as a Robust Predictor for Shunt-Dependent Hydrocephalus After Spontaneous Supratentorial Intracerebral Hemorrhage

OBJECTIVE

Spontaneous intracerebral hemorrhage (ICH) is a common stroke subtype, and patients often develop intraventricular hemorrhage (IVH) and hydrocephalus (H). It is essential to promptly recognize factors that can predict the need for permanent cerebrospinal fluid shunt. This study aims to assess the potential of the IVH score as a predictor for shunt-dependent H in ICH patients.

METHODS

We retrospectively reviewed data from 296 patients with spontaneous supratentorial ICH. Clinical and radiographic data were analyzed. IVH scores were calculated based on initial brain computed tomography scans. A multivariable logistic regression analysis was performed to identify independent predictors of shunt-dependent H, and a receiver operating characteristic curve was generated for the IVH score.

RESULTS

Among the 296 ICH patients, 25 (8.4%) required permanent cerebrospinal fluid shunt placement. The IVH score was identified as the sole significant independent predictor of shunt-dependent H (P < 0.01), with an odds ratio of 1.13 and a 95% confidence interval between 1.04 and 1.22. With each unit increase in the IVH score, the likelihood of shunt dependence rises by 13%. The area under the curve for the IVH score as a predictor of shunt-dependent H was 0.818. With an IVH score threshold of 6.5, the sensitivity was 80.0%, and the specificity was 26.6%.

CONCLUSIONS

The IVH score is a valuable predictor of shunt-dependent H in patients with spontaneous supratentorial ICH. Its simplicity allows for easy integration into routine clinical practice, aiding in better patient risk stratification and informed decision-making regarding permanent CSF shunt placement.

Blood-Based Biomarkers in Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is one of the most lethal subtypes of stroke, associated with high morbidity and mortality. Prevention of hematoma growth and perihematomal edema expansion are promising therapeutic targets currently under investigation. Despite recent improvements in the management of ICH, the ideal treatments are still to be determined. Early stratification and triage of ICH patients enable the adjustment of the standard of care in keeping with the personalized medicine principles. In recent years, research efforts have been concentrated on the development and validation of blood-based biomarkers. The benefit of looking for blood candidate markers is obvious because of their acceptance in terms of sample collection by the general population compared to any other body fluid. Given their ease of accessibility in clinical practice, blood-based biomarkers have been widely used as potential diagnostic, predictive, and prognostic markers. This review identifies some relevant and potentially promising blood biomarkers for ICH. These blood-based markers are summarized by their roles in clinical practice. Well-designed and large-scale studies are required to validate the use of all these biomarkers in the future.

Neutrophil percentage to albumin ratio is associated with stroke-associated pneumonia and poor outcome in patients with spontaneous intracerebral hemorrhage

Background

The purpose of this study was to investigate the diagnostic performance of the neutrophil percentage-to-albumin ratio (NPAR) for predicting stroke-associated pneumonia (SAP) and functional outcome in patients with intracerebral hemorrhage (ICH).

Methods

We analyzed our prospective database of consecutive ICH patients who were admitted to the First Affiliated Hospital of Chongqing Medical University from January 2016 to September 2021. We included subjects with a baseline computed tomography available and a complete NPAR count performed within 6h of onset. The patients' demographic and radiological characteristics were analyzed. Good outcome was defined as a modifed Rankin Scale score of 0-3 at 90 days. Poor outcome was defined as a modifed Rankin Scale score of 4-6 at 90 days. Multivariable logistic regression models were used to investigate the association between NPAR, SAP, and functional outcome. Receiver operating characteristic (ROC) curve analysis was conducted to identify the optimal cutoff of NPAR to discriminate between good and poor outcomes in ICH patients.

Results

A total of 918 patients with ICH confirmed by non-contrast computed tomography were included. Of those, 316 (34.4%) had SAP, and 258 (28.1%) had poor outcomes. Multivariate regression analysis showed that higher NPAR on admission was an independent predictor of SAP (adjusted odds ratio: 2.45; 95% confidence interval, 1.56-3.84; P<0.001) and was associated with increased risk of poor outcome (adjusted odd ratio:1.72; 95% confidence interval, 1.03-2.90; P=0.040) in patients with ICH. In ROC analysis, an NPAR of 2 was identified as the optimal cutoff value to discriminate between good and poor functional outcomes.

Conclusion

Higher NPAR is independently associated with SAP and poor functional outcome in patients with ICH. Our findings suggest that early prediction of SAP is feasible by using a simple biomarker NPAR.

The trend of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in spontaneous intracerebral hemorrhage and the predictive value of short-term postoperative prognosis in patients

Background

Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) play an important role in the inflammatory response in various diseases, but the role in the course of spontaneous intracerebral hemorrhage (ICH) is unclear.

Methods

This study retrospectively collected baseline characteristics and laboratory findings, including NLR and PLR at different time points, from spontaneous ICH patients undergoing surgery between January 2016 and June 2021. Patients were scored using the modified Rankin Scale (mRS) to evaluate their functional status at 30 days post-operation. Patients with mRS score ≥3 were defined as poor functional status, and mRS score <3 was defined as good functional status. The NLR and PLR were calculated at admission, 48 h after surgery and 3-7 days after surgery, respectively, and their trends were observed by connecting the NLR and PLR at different time points. Multivariate logistic regression analysis was used to identify independent risk factors affecting the prognosis of ICH patients at 30 days after surgery.

Results

A total of 101 patients were included in this study, and 59 patients had a poor outcome at 30 days after surgery. NLR and PLR gradually increased and then decreased, peaking at 48 h after surgery. Univariate analysis demonstrated that admission Glasgow Coma Scale (GCS) score, interval from onset to admission, hematoma location, NLR within 48 h after surgery and PLR within 48 h after surgery were associated with poor 30-day prognosis. In multivariate logistic regression analysis, NLR within 48 h after surgery (OR, 1.147; 95% CI, 1.005, 1.308; P, 0.042) was an independent risk factor for 30-day after surgery prognosis in spontaneous ICH patients.

Conclusion

In the course of spontaneous intracerebral hemorrhage, NLR and PLR initially increased and subsequently decreased, reaching their peak values at 48 h after surgery. High NLR within 48 h after surgery was an independent risk factor for poor prognosis 30 days after surgery in spontaneous ICH patients.

Spatiotemporal Cofilin Signaling, Microglial Activation, Neuroinflammation, and Cognitive Impairment Following Hemorrhagic Brain Injury

Intracerebral hemorrhage (ICH) is a significant health concern associated with high mortality. Cofilin plays a crucial role in stress conditions, but its signaling following ICH in a longitudinal study is yet to be ascertained. In the present study, we examined the cofilin expression in human ICH autopsy brains. Then, the spatiotemporal cofilin signaling, microglia activation, and neurobehavioral outcomes were investigated in a mouse model of ICH. Human autopsy brain sections from ICH patients showed increased intracellular cofilin localization within microglia in the perihematomal area, possibly associated with microglial activation and morphological changes. Various cohorts of mice were subjected to intrastriatal collagenase injection and sacrificed at time points of 1, 3, 7, 14, 21, and 28 days. Mice suffered from severe neurobehavioral deficits after ICH, lasting for 7 days, followed by a gradual improvement. Mice suffered post-stroke cognitive impairment (PSCI) both acutely and in the chronic phase. Hematoma volume increased from day 1 to 3, whereas ventricle size increased from day 21 to 28. Cofilin protein expression increased in the ipsilateral striatum on days 1 and 3 and then decreased from days 7 to 28. An increase in activated microglia was observed around the hematoma on days 1 to 7, followed by a gradual reduction up to day 28. Around the hematoma, activated microglia showed morphological changes from ramified to amoeboid. mRNA levels of inflammatory [tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), and interleukin-6 (IL-6) and anti-inflammatory markers [interleukin-10 (IL-10), transforming growth factor-β TGF-β, and arginase I (Arg1)] increased during the acute phase and decreased in the chronic phase. Blood cofilin levels increased on day 3 and matched the increase in chemokine levels. slingshot protein phosphatase 1 (SSH1) protein, which activates cofilin, was increased from day 1 to 7. These results suggest that microglial activation might be the sequel of cofilin overactivation following ICH, leading to widespread neuroinflammation and consequent PSCI.

An Ambiguous Role for Fever in Worsening Outcome After Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) accounts for 10-15% of all strokes and leaves most survivors with impairments. Fever, a rise in the thermoregulatory set point, complicates ICH. This review summarizes ICH fever studies and employs meta-analytic techniques to explore the relationship between fever and ICH. We discuss methodological considerations for future studies and provide an overview of mechanisms by which fever, and its treatment, may impact ICH. We searched the PubMed database using the following terms: ((fever OR hyperthermia) AND (intracerebral hemorrhage OR intraparenchymal hemorrhage OR intracerebral haemorrhage OR intraparenchymal haemorrhage)). Our search returned 727 studies, of which 21 were included in our final analysis, consisting of 19 clinical, and two preclinical, studies. We conducted a meta-analysis on the clinical data to quantify how fever is related to mortality, functional outcomes, and intraventricular hemorrhage. Analysis of clinical studies suggested that fever causes an increased risk of mortality but does not appear to be associated with poor outcomes among survivors, making it difficult to ascertain the extent of harm caused by post-ICH fever or the benefits of its treatment. Perhaps these inconsistencies stem from variable fever definitions, and temperature measurement and fever treatment protocols. Additionally, the lack of mechanistic data in clinical studies coupled with preclinical studies showing no harmful effects of moderate bouts of hyperthermia raise concerns about the direct contribution of hyperthermia and fever in post ICH outcome. Overall, the significance of temperature increases after ICH is unclear, making this an important area for future research.

Systemic inflammation and immune index predicting outcomes in patients with intracerebral hemorrhage

OBJECT

Recent evidence has suggested that systemic inflammatory and immune index (SIRI) and systematic inflammation index (SII) could predict prognosis in stroke patients. This study aimed to determine the effects of SIRI and SII on predicting in-hospital infections and unfavorable outcomes in patients with acute intracerebral hemorrhage (ICH).

METHODS

We used the data from a prospective and registry-based study recruiting ICH patients between January 2014 and September 2016 in a single comprehensive stroke center. All patients were stratified by quartiles of SIRI or SII. Logistic regression analysis was used to estimate the associations with follow-up prognosis. The receiver operating characteristics (ROC) curves were performed to examine the predictive utility of these indexes for infections and prognosis.

RESULTS

Six hundred and forty spontaneous ICH patients were enrolled in this study. Compared with the lowest quartile (Q1), SIRI or SII values both showed positive correlations with increased risks for poor 1-month outcomes (adjusted ORs in Q4 was 2.162 [95% CI: 1.240-3.772] for SIRI, 1.797 [95% CI: 1.052-3.070] for SII). Additionally, a higher level of SIRI, but not SII, was independently associated with a higher risk of infections and an unfavorable 3-month prognosis. The C-statistic for the combined SIRI and ICH score was higher than SIRI or ICH score alone for predicting in-hospital infections and poor outcomes.

CONCLUSION

Elevated SIRI values were associated with in-hospital infections and poor functional outcomes. It may provide a new biomarker for ICH prognosis prediction, especially in the acute stage.

The roles of chemokines following intracerebral hemorrhage in animal models and humans

Intracerebral hemorrhage (ICH) is one common yet devastating stroke subtype, imposing considerable burdens on families and society. Current guidelines are limited to symptomatic treatments after ICH, and the death rate remains significant in the acute stage. Thus, it is crucial to promote research to develop new targets on brain injury after ICH. In response to hematoma formation, amounts of chemokines are released in the brain, triggering the infiltration of resident immune cells in the brain and the chemotaxis of peripheral immune cells via the broken blood-brain barrier. During the past decades, mounting studies have focused on the roles of chemokines and their receptors in ICH injury. This review summarizes the latest advances in the study of chemokine functions in the ICH. First, we provide an overview of ICH epidemiology and underlying injury mechanisms in the pathogenesis of ICH. Second, we introduce the biology of chemokines and their receptors in brief. Third, we outline the roles of chemokines in ICH according to subgroups, including CCL2, CCL3, CCL5, CCL12, CCL17, CXCL8, CXCL12, and CX3CL1. Finally, we summarize current drug usage targeting chemokines in ICH and other cardio-cerebrovascular diseases. This review discusses the expressions of these chemokines and receptors under normal or hemorrhagic conditions and cell-specific sources. Above all, we highlight the related data of these chemokines in the progression and outcomes of the ICH disease in preclinical and clinical studies and point to therapeutic opportunities targeting chemokines productions and interactions in treating ICH, such as accelerating hematoma absorption and alleviating brain edema.

The predictive value of neutrophil to lymphocyte ratio on 30-day outcomes in spontaneous intracerebral hemorrhage patients after surgical treatment: A retrospective analysis of 128 patients

Objective

The purpose of this study was to explore the predictive value of the neutrophil-to-lymphocyte ratio (NLR) on 30-day outcomes in patients with spontaneous intracerebral hemorrhage (ICH) after surgical treatment.

Methods

This retrospective study utilized data from patients with ICH who underwent craniotomy or minimally invasive puncture and drainage (MIPD) between January 2015 and June 2021. The patients meeting the inclusion criteria were divided into two groups according to 30-day outcomes, namely, the favorable outcome group and the poor outcome group. Sex, age, time from onset to admission, vital signs at admission, admission Glasgow Coma Scale (GCS) score, diabetes mellitus, hypertension, hematoma volume, hematoma location, surgical approach, and NLR at different time points were all recorded and analyzed.

Results

A total of 128 patients were finally enrolled in this study, including 32 and 96 patients in the favorable outcome group and the poor outcome group, respectively. During the course of ICH, the changing trend of NLR was to increase first and then decrease and peaked within 48 h after surgery. In the univariate analysis, systolic blood pressure, admission GCS score, hematoma volume, surgical approach, and NLR within 48 h after surgery were statistically significant. In the multivariable analysis, NLR within 48 h after surgery (odds ratio [OR] = 1.342, p < 0.001) was an independent risk factor of the 30-day outcomes in patients with ICH after surgical treatment. The receiver operating characteristic (ROC) analysis showed that the best predictive cut-off value for NLR within 48 h after surgery was 12.35 [sensitivity 82.9%, specificity 81.8%, and area under the curve (AUC) 0.877] and 14.46 (sensitivity 55.1%, specificity 87.5%, and area under the curve 0.731) for the MIPD group and the craniotomy group, respectively.

Conclusions

In the process of ICH, the value of NLR was increased first and then decreased and peaked within 48 h after surgery. NLR within 48 h after surgery was an independent risk factor of the 30-day outcomes in patients with ICH. The peak NLR >12.35 or 14.46 in patients receiving MIPD or craniotomy reflected a poor prognosis, respectively.

Central Nervous System Tissue Regeneration after Intracerebral Hemorrhage: The Next Frontier

Despite marked advances in surgical techniques and understanding of secondary brain injury mechanisms, the prognosis of intracerebral hemorrhage (ICH) remains devastating. Harnessing and promoting the regenerative potential of the central nervous system may improve the outcomes of patients with hemorrhagic stroke, but approaches are still in their infancy. In this review, we discuss the regenerative phenomena occurring in animal models and human ICH, provide results related to cellular and molecular mechanisms of the repair process including by microglia, and review potential methods to promote tissue regeneration in ICH. We aim to stimulate research involving tissue restoration after ICH.

The Prognostic Value of the Acute Phase Systemic Immune-Inflammation Index in Patients With Intracerebral Hemorrhage

Background and Purpose: The systemic immune–inflammation index (SII) is a novel prognostic index in various diseases. We evaluated the predictive value of SII in patients with intracerebral hemorrhage (ICH).

Methods: Patients with primary spontaneous ICH were enrolled. SII was constructed based on peripheral platelet (P), neutrophil (N), and lymphocyte (L) and defined as P^*N/L. In addition to admission testing, acute phase SII was collected to analyze the potential dynamic change. Poor outcome was defined as modified Rankin Scale of more than 3 at 90 days.

Results: We included 291 patients; 98 (34%) achieved favorable functional outcomes. Day-1 SII was higher and was more related to poor outcome than was admission SII. Median time of day-1 SII was 29 h from onset. Day-1 SII had an OR in outcome (mRS >3) 1.74 (95% CI = 1.03–3.00, p = 0.04). The binary cutoff point of SII calculated using the area under the curve (AUC) method was 1,700 × 10⁹/L, AUC 0.699 (95% CI = 0.627–0.774) (sensitivity 53.3%, specificity 77.3%) (OR = 2.36, 95% CI = 1.09–5.26, p = 0.03).

Conclusions: SII, especially day-1 SII, was highly associated with 90-day functional outcome in patients with ICH and could be used to predict outcomes.

Neutrophil extracellular traps (NETs) infiltrate haematoma and surrounding brain tissue after intracerebral haemorrhage: A post-mortem study

AIMS

Because of their prothrombotic and neuroinflammatory effects, neutrophils and neutrophil extracellular traps (NETs) represent interesting therapeutic targets for spontaneous intracerebral haemorrhage (sICH). We investigated the presence, spatial and temporal distribution of NETs in a human sICH post-mortem study.

METHODS

From 2005 to 2019, all sICH patients who came to autopsy within the first month after stroke were included and grouped according to the timing of death: 72 h, 4-7 days, 8-15 days and >15 days after ICH onset. Paraffin-embedded tissue was extracted from four strategic areas: haematoma, peri-haematomal area, ipsilateral surrounding brain tissue and a control contralateral area. Myeloperoxidase and histone H3 citrulline were immunolabelled to detect neutrophils and NETs respectively.

RESULTS

Neutrophils were present in the brains of the 14 cases (4 men, median age: 78 years) and NETs were found in 7/14 cases. Both neutrophils and NETs were detected within the haematoma but also in the surrounding tissue. The appearance of neutrophils and NETs was time-dependent, following a two-wave pattern: during the first 72 h and between 8 and 15 days after ICH onset. Qualitative examination showed that neutrophils and NETs were mainly located around dense fibrin fibres within the haematoma.

CONCLUSIONS

These observations provide evidence for NETs infiltration in the brain of patients who die from sICH. NETs might interact with early haemostasis within the haematoma core, and with the surrounding neuroinflammatory response. These findings open research perspectives for NETs in the treatment of sICH injuries.

Systemic Immune-Inflammation (SII) index predicts poor outcome after spontaneous supratentorial intracerebral hemorrhage

BACKGROUND AND AIMS

In experimental models, enhanced inflammation contributes to secondary brain injury in spontaneous intracerebral hemorrhage (ICH). Several inflammatory markers have investigated in humans with inconclusive results. Here, we report the relationship between Systemic Immune-Inflammation (SII) Index and outcome.

METHODS

We reviewed the medical records of 239 supratentorial spontaneous ICH patients. Patients were dichotomized based on modified Rankin Scale (mRS) at discharge in good (mRS 0-3) and poor (mRS 4-6) outcome. Demographic, clinical, laboratory and imaging data at admission were compared for both groups. SII index was calculated as [(Platelet counts x Absolute Neutrophil Counts (ANC)/Absolute Lymphocyte Counts (ALC))/1000]. Logistic regression analyses were performed to determine the association between markers of inflammation (ANC, ALC, Platelets, SII index) and outcome adjusting for baseline differences.

RESULTS

Sixty-two percent of patients had poor outcome (median [IQR] age= 60 [52-71] years). Patients with poor outcome had lower Glasgow coma scale, larger hematoma volumes, and higher incidence of diabetes and intraventricular extension (p<0.05 for each variable). In univariate analysis, ANC and SII index were independently associated with poor outcome (p<0.05). In multivariate analysis, only SII index remained significantly associated with poor outcome (OR=1.34, 95% CI=1.04-1.72, p=0.02). ROC analysis showed that adjusted SII index is a good discriminator for poor outcome (AUC=0.89, 95% CI=0.84-0.93; P <0.0001), with the best cut-off value being 0.73 (Sensitivity 95%, Specificity 71%).

CONCLUSIONS

In patients with supratentorial spontaneous ICH early SII index is an independent predictor of poor outcome at time of hospital discharge.

The intracerebral hemorrhage blood transcriptome in humans differs from the ischemic stroke and vascular risk factor control blood transcriptomes

Understanding how the blood transcriptome of human intracerebral hemorrhage (ICH) differs from ischemic stroke (IS) and matched controls (CTRL) will improve understanding of immune and coagulation pathways in both disorders. This study examined RNA from 99 human whole-blood samples using GeneChip® HTA 2.0 arrays to assess differentially expressed transcripts of alternatively spliced genes between ICH, IS and CTRL. We used a mixed regression model with FDR-corrected p(Dx) < 0.2 and p < 0.005 and |FC| > 1.2 for individual comparisons. For time-dependent analyses, subjects were divided into four time-points: 0(CTRL), <24 h, 24-48 h, >48 h; 489 transcripts were differentially expressed between ICH and CTRL, and 63 between IS and CTRL. ICH had differentially expressed T-cell receptor and CD36 genes, and iNOS, TLR, macrophage, and T-helper pathways. IS had more non-coding RNA. ICH and IS both had angiogenesis, CTLA4 in T lymphocytes, CD28 in T helper cells, NFAT regulation of immune response, and glucocorticoid receptor signaling pathways. Self-organizing maps revealed 4357 transcripts changing expression over time in ICH, and 1136 in IS. Understanding ICH and IS transcriptomes will be useful for biomarker development, treatment and prevention strategies, and for evaluating how well animal models recapitulate human ICH and IS.

Rapid neuroinflammatory changes in human acute intracerebral hemorrhage

OBJECTIVE

Spontaneous intracerebral hemorrhage (ICH) is the commonest form of hemorrhagic stroke and is associated with a poor prognosis. Neurosurgical removal of intracerebral hematoma has limited benefit and no pharmacotherapies are available. In acute ICH, primary tissue damage is followed by secondary pathology, where the cellular and neuroinflammatory changes are poorly understood.

METHODS

We studied histological changes in postmortem tissue from a cohort of spontaneous supra-tentorial primary ICH cases (n = 27) with survival of 1-12 days, compared to a matched control group (n = 16) examined in corresponding regions. Hematoxylin-eosin and microglial (Iba1) immunolabelled sections were assessed at 0-2, 3-5, and 7-12 days post-ICH.

RESULTS

Peri-hematoma, the observed ICH-related changes include edema, tissue neutrophils and macrophages from day 1. Ischemic neurons and swollen endothelial cells were common at day 1 and universal after day 5, as were intramural erythrocytes within small vessel walls. Activated microglia were evident at day 1 post-ICH. There was a significant increase in Iba1 positive area fraction at 0-2 (threefold), 3-5 (fourfold), and 7-12 days post ICH (ninefold) relative to controls. Giant microglia were detected peri-hematoma from day 5 and consistently 7-12 days post-ICH.

INTERPRETATION

Our data indicate that neuroinflammatory processes commence from day 1 post-ICH with changing microglial size and morphology following ICH and up to day 12. From day 5 some microglia exhibit a novel multiply nucleated morphology, which may be related to changing phagocytic function. Understanding the time course of neuroinflammatory changes, post-ICH may reveal novel targets for therapy and brain restoration.

Histology of Brain Trauma and Hypoxia-Ischemia

Forensic pathologists encounter hypoxic-ischemic (HI) brain damage or traumatic brain injuries (TBI) on an almost daily basis. Evaluation of the findings guides decisions regarding cause and manner of death. When there are gross findings of brain trauma, the cause of death is often obvious. However, microscopic evaluation should be used to augment the macroscopic diagnoses. Histology can be used to seek evidence for TBI in the absence of gross findings, e.g., in the context of reported or suspected TBI. Estimating the survival interval after an insult is often of medicolegal interest; this requires targeted tissue sampling and careful histologic evaluation. Retained tissue blocks serve as forensic evidence and also provide invaluable teaching and research material. In certain contexts, histology can be used to demonstrate nontraumatic causes of seemingly traumatic lesions. Macroscopic and histologic findings of brain trauma can be confounded by concomitant HI brain injury when an individual survives temporarily after TBI. Here we review the histologic approaches for evaluating TBI, hemorrhage, and HI brain injury. Amyloid precursor protein (APP) immunohistochemistry is helpful for identifying damaged axons, but patterns of damage cannot unambiguously distinguish TBI from HI. The evolution of hemorrhagic lesions will be discussed in detail; however, timing of any lesion is at best approximate. It is important to recognize artifactual changes (e.g., dark neurons) that can resemble HI damage. Despite the shortcomings, histology is a critical adjunct to the gross examination of brains.

Neutrophil-to-Lymphocyte Ratio in Acute Cerebral Hemorrhage: a System Review

Spontaneous intracerebral hemorrhage (ICH) accounts for approximately 10 to 30% of all acute cerebrovascular events, and it is the type of stroke associated with the highest rates of mortality and residual disability. The inflammatory response is early triggered by hematoma components and can enhance the damage within the hemorrhagic brain. Assessment of peripheral biomarkers of inflammation could contribute to increase knowledge about some of the mechanisms involved in the ICH-induced injury and yield information on the disease course. The neutrophil-to-lymphocyte ratio (NLR) integrates information on both the innate and adaptive compartments of the immunity and represents a reliable measure of the inflammatory burden. The aim of the current review is to highlight the available evidence about the relationships between the NLR and clinical outcome in patients with acute ICH and provide critical insights into the underlying pathophysiology. Since no therapy targeting ICH-induced primary injury has yielded conclusive benefits and ICH treatment remains mainly supportive within a framework of general critical care management, these findings could also contribute to identify new potential targets for neuroprotection and develop novel therapeutic strategies.

Early increase of neutrophil-to-lymphocyte ratio predicts 30-day mortality in patients with spontaneous intracerebral hemorrhage

Aims

To examine whether early rise of neutrophil‐to‐lymphocyte ratio (NLR) after patient hospitalization correlates with 30‐day mortality in patients with spontaneous intracerebral hemorrhage (ICH).

Methods

This retrospective study included all patients receiving treatment for spontaneous ICH between January 2015 and September 2016 at the Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences in Shanghai, China. NLR was determined at admission (T1), at 24‐48 hours (T2) and 5‐7 days (T3). NLR and clinicopathologic features were compared between those who survived for >30 days vs not. Multivariate regression was used to identify risk factors for 30‐day mortality.

Results

A total of 275 subjects were included in the analysis: 235 survived for at least 30 days; the remaining 40 subjects died within 30 days. The patients who died within 30 days had higher ICH score, larger ICH volume, and lower GCS score (all P < 0.05). In comparison with the baseline (NLR_T1), NLR at 24‐48 hours (NLR_T2) and 5‐7 days (NLR_T3) was significantly higher in patients who died within 30 days (P < 0.05), but not in patients surviving for >30 days. In the multivariate analysis, the 30‐day mortality was associated with both NLR_T2 (OR 1.112, 95%CI 1.032‐1.199, P = 0.006) and NLR_T3 (OR 1.163, 95%CI 1.067‐1.268, P = 0.001). Spearman correlation analysis showed that both NLR_T2 and NLR_T3 correlated inversely with GCS score and positively with ICH score and ICH volume at the baseline.

Conclusions

Early rise of NLR predicts 30‐day mortality in patients with spontaneous ICH.

Neutrophil-to-lymphocyte ratio improves outcome prediction of acute intracerebral hemorrhage

BACKGROUND

The inflammatory response plays a role in determining the course of intra-cerebral hemorrhage (ICH) and immune parameters may have prognostic value. The aim of the study was to determine whether the peripheral leukocyte counts and neutrophil-to-lymphocyte ratio (NLR) were associated to 30-day functional status after ICH, and improved the accuracy of outcome prediction when added to the Modified ICH score.

METHODS

We retrospectively identified consecutive patients with spontaneous ICH who underwent blood sampling and cranial CT neuroimaging within 24 h from onset. Total white blood cells (WBC), absolute neutrophil count (ANC) and absolute lymphocyte count (ALC) were collected, and the NLR computed as the ANC to ALC ratio. The study endpoint was 30-day functional status; poor outcome was defined as death or major disability (modified Rankin Scale score ≥ 3).

RESULTS

Two hundred and eight patients were enrolled, of which 111 (53.4%) had a modified Rankin Scale score ≥ 3 at 30 days from ICH. At multivariate analysis, the WBC (adjusted odd ratio [_adjOR] for 1000 leukocytes increase 1.20, 95% confidence interval [CI] 1.05-1.38), ANC (_adjOR for 1000 neutrophils increase 1.34, 95% CI 1.14-1.57), ALC (_adjOR for 1000 lymphocytes increase 0.34, 95% CI 0.20-0.59) and NLR (_adjOR for 1-point increase 1.49, 95% CI 1.24-1.79) were independently associated with 30-day poor outcome. Predictive accuracy of the Modified ICH score was enhanced by adding the NLR.

CONCLUSIONS

The NLR was associated with 30-day mortality and morbidity after ICH, and improved the accuracy of outcome prediction when added to the Modified ICH score.

Increased Expression of Mitochondrial Inner-Membrane Protein Mpv17 After Intracerebral Hemorrhage in Adult Rats

The Mpv17 gene encodes a mitochondrial inner-membrane protein that has been implicated in several cell activities. Almost all studies have previously indicated that loss of function or gene-inactivated in Mpv17 can induce the development of disease. Here, we explored the roles of Mpv17 protein in the pathophysiology of intracerebral hemorrhage (ICH). An ICH rat model was established and assessed by behavioral tests. Using western blot and immunohistochemistry, significant up-regulation of Mpv17 was found in neurons in brain areas surrounding the hematoma following ICH. The increase of Mpv17 expression was found to be accompanied by the enhanced expression of p53, Bax, cytochrome c (Cyt c) and active caspase-3, and decreased expression of Bcl-2 in the pathological process of rat ICH. Furthermore, immunofluorescent staining revealed that Mpv17 co-localized with p53, Bax and active caspase-3 in neurons, suggesting its biological function in the process of neuronal apoptosis. Our in vitro study, using Mpv17 RNA interference in primary cortical neurons, indicated that Mpv17 might exert its anti-apoptotic function in neuronal apoptosis. Thus, Mpv17 may play a role in protecting the brain from secondary damage following ICH.

Serum ischemia-modified albumin levels in children with epileptic seizures

OBJECTIVES

The aim of the present study was to determine the level of ischemia-modified albumin (IMA) in children with epileptic seizures (ESs) and its relation with the seizure duration.

METHODS

The study was performed with 88 children as a prospective case-control study. Blood samples for IMA were obtained from 57 patients (mean age [SD], 50.86 [51.15] months) within 3 hours after ES and 31 healthy control subjects (mean age [SD], 53.13 [40.87] months). Ischemia-modified albumin was measured by the albumin cobalt binding test.

RESULTS

Although the mean (SD) of serum IMA level of the patients with seizure was 13.66 (13.16) U/mL, the mean (SD) of serum IMA level for the control group was 3.73 (1.93) U/mL. Ischemia-modified albumin levels were significantly higher in patients with seizure, compared with that in the control group (P < 0.01). When patients were grouped in itself according to the duration of ESs, the levels of IMA were detected to be increased in patients as the duration of seizures was lengthened.

CONCLUSIONS

Increased IMA levels after seizures suggest that IMA assay during seizure may be useful for predicting the diagnosis and severity of convulsion.

Inflammation in intracerebral hemorrhage: from mechanisms to clinical translation

Intracerebral hemorrhage (ICH) accounts for 10-15% of all strokes and is associated with high mortality and morbidity. Currently, no effective medical treatment is available to improve functional outcomes in patients with ICH. Potential therapies targeting secondary brain injury are arousing a great deal of interest in translational studies. Increasing evidence has shown that inflammation is the key contributor of ICH-induced secondary brain injury. Inflammation progresses in response to various stimuli produced after ICH. Hematoma components initiate inflammatory signaling via activation of microglia, subsequently releasing proinflammatory cytokines and chemokines to attract peripheral inflammatory infiltration. Hemoglobin (Hb), heme, and iron released after red blood cell lysis aggravate ICH-induced inflammatory injury. Danger associated molecular patterns such as high mobility group box 1 protein, released from damaged or dead cells, trigger inflammation in the late stage of ICH. Preclinical studies have identified inflammatory signaling pathways that are involved in microglial activation, leukocyte infiltration, toll-like receptor (TLR) activation, and danger associated molecular pattern regulation in ICH. Recent advances in understanding the pathogenesis of ICH-induced inflammatory injury have facilitated the identification of several novel therapeutic targets for the treatment of ICH. This review summarizes recent progress concerning the mechanisms underlying ICH-induced inflammation. We focus on the inflammatory signaling pathways involved in microglial activation and TLR signaling, and explore potential therapeutic interventions by targeting the removal of hematoma components and inhibition of TLR signaling.

Chemokines and their receptors in intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating clinical event which results in a high rate of disability and death. At present, no effective treatment is available for ICH. Accumulating evidence suggests that inflammatory responses contribute significantly to the ICH-induced secondary brain outcomes. During ICH, inflammatory cells accumulate at the ICH site attracted by gradients of chemokines. This review summarizes recent progress in ICH studies and the chemoattractants that act during the injury and focuses on and introduces the basic biology of the chemokine monocyte chemoattractant protein-1 (MCP1) and its role in the progression of ICH. Better understanding of MCP1 signaling cascade and the compensation after its inhibition could shed light on the development of effective treatments for ICH.

VAP-1/SSAO plasma activity and brain expression in human hemorrhagic stroke

BACKGROUND

Vascular adhesion protein-1 (VAP-1) is a cell surface and circulating enzyme that belongs to the semicarbazide-sensitive amine oxidase (SSAO) family, which oxidatively deaminates primary amines and is implicated in leukocyte extravasation. Our aim was to investigate the alteration of soluble VAP-1/SSAO activity in plasma samples after acute intracerebral hemorrhage (ICH) and its presence in human ICH brain tissue.

METHODS

VAP-1/SSAO activity was determined in plasma of 66 ICH patients and 58 healthy controls. In addition, we assessed the expression of VAP-1/SSAO in postmortem brain tissue from hemorrhagic stroke patients by Western blot and immunohistochemistry.

RESULTS

We observed significantly higher levels of plasma VAP-1/SSAO activity in patients with ICH compared to matched elderly controls (p = 0.001). Plasma VAP-1/SSAO activity <2.7 pmol/min·mg and baseline ICH volume <17 ml were independent predictors of neurological improvement after 48 h (OR 6.8, 95% CI 1.14-41.67, p = 0.035, and OR 10.64, 95% CI 1.1-100, p = 0.041, respectively), after adjustment for baseline stroke severity. We also found that membrane-bound VAP-1/SSAO levels were lower in the perihematoma region than in the corresponding contralateral brain areas of patients deceased due to ICH (p = 0.024).

CONCLUSIONS

Our data demonstrate that plasma VAP-1/SSAO activity is increased in ICH and predicts neurological outcome, suggesting a possible contribution of the soluble protein in secondary brain damage. Furthermore, anti-VAP-1/SSAO strategies might be a promising approach to prevent neurological worsening following ICH.

Peripheral leukocyte counts and outcomes after intracerebral hemorrhage

Background

Intracerebral hemorrhage (ICH) is a devastating disease that carries a 30 day mortality of approximately 45%. Only 20% of survivors return to independent function at 6 months. The role of inflammation in the pathophysiology of ICH is increasingly recognized. Several clinical studies have demonstrated an association between inflammatory markers and outcomes after ICH; however the relationship between serum biomarkers and functional outcomes amongst survivors has not been previously evaluated. Activation of the inflammatory response as measured by change in peripheral leukocyte count was examined and assessment of mortality and functional outcomes after ICH was determined.

Findings

Patients with spontaneous ICH admitted to a tertiary care center between January 2005 and April 2010 were included. The change in leukocyte count was measured as the difference between the maximum leukocyte count in the first 72 hours and the leukocyte count on admission. Mortality was the primary outcome. Secondary outcomes were mortality at 1 year, discharge disposition and the modified Barthel index (MBI) at 3 months compared to pre-admission MBI. 423 cases were included. The in-hospital mortality was 30.4%. The change in leukocyte count predicted worse discharge disposition (OR = 1.258, p = 0.009). The change in leukocyte count was also significantly correlated with a decline in the MBI at 3 months. These relationships remained even after removal of all patients with evidence of infection.

Conclusions

Greater changes in leukocyte count over the first 72 hours after admission predicted both worse short term and long term functional outcomes after ICH.

Perihematomal pathological changes in neurons and astrocytes following acute cerebral hemorrhage

We aim to investigate the pathological temporospatial characteristics of brain cell injury in the perihematomal areas. Brain autopsy samples from 44 consecutive cases of intracerebral hemorrhage were processed and analyzed following immunohistochemical staining for neurofilament (NF) and glial fibrillary acidic protein (GFAP). NF and GFAP positive cells were scored and graded according to the distance from the hematoma and the time from the onset of hematoma formation. The tissues from the same region on the contralateral side of the brain were used as controls. Neurons in the perihematomal areas exhibited pyknosis or swollen necrosis, while astrocytes were swollen. Morphological abnormalities pertaining to NF appearance were attenuated with increasing distance from the hematoma wall, but were exacerbated with prolonged bleeding time. The level of NF staining abnormality was positively correlated with time from the onset of hematoma within 7 days of intracerebral hemorrhage. In contrast, the intensity of GFAP staining was negatively correlated with time from the onset of hematoma formation. This immunoreactivity was significantly higher closer to hematoma. Taken together, these data indicate that pathological alterations in neurons and astrocytes in the perihematomal area change with time from the onset of hematoma formation.

Preclinical and clinical research on inflammation after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is one of the most lethal stroke subtypes. Despite the high morbidity and mortality associated with ICH, its pathophysiology has not been investigated as well as that of ischemic stroke. Available evidence from preclinical and clinical studies suggests that inflammatory mechanisms are involved in the progression of ICH-induced secondary brain injury. For example, in preclinical ICH models, microglial activation has been shown to occur within 1h, much earlier than neutrophil infiltration. Recent advances in our understanding of neuroinflammatory pathways have revealed several new molecular targets, and related therapeutic strategies have been tested in preclinical ICH models. This review summarizes recent progress made in preclinical models of ICH, surveys preclinical and clinical studies of inflammatory cells (leukocytes, macrophages, microglia, and astrocytes) and inflammatory mediators (matrix metalloproteinases, nuclear factor erythroid 2-related factor 2, heme oxygenase, and iron), and highlights the emerging areas of therapeutic promise.

Ischemia-modified albumin levels in cerebrovascular accidents

BACKGROUND

Previous studies have demonstrated that ischemia-modified albumin (IMA) is a useful marker for the diagnosis of ischemic events. It was also recently demonstrated that IMA levels increase in the acute phase of cerebrovascular diseases. Yet the data regarding IMA levels in various types of cerebrovascular events are insufficient. The aim of this study was to evaluate IMA levels in various types of cerebrovascular events such as ischemic stroke, subarachnoid hemorrhage (SAH), and intracranial hemorrhage.

METHODS

This case-controlled study consisted of 106 consecutive patients, 43 with brain infarction (BI), 11 with brain hemorrhage (ICH), 52 with SAH, and a 43-member control group. We investigated whether there was a statistical correlation between these 3 groups and the control group. The relations among the 3 groups were also examined. Comparisons among groups were done with analysis of variance.

RESULTS

Mean serum IMA levels were 0.280 +/- 0.045 absorbance units (ABSU) for BI patients, 0.259 +/- 0.053 ABSU for ICH patients, 0.243 +/- 0.061 ABSU for SAH patients, and 0.172 +/- 0.045 ABSU for the control group.There was a statistically significant difference between the mean IMA levels of BI, ICH, and SAH patients and the mean control patient IMA levels (P b .0001).

CONCLUSIONS

Ischemia-modified albumin levels are high in cerebrovascular diseases. Ischemia-modified albumin measurement can also be used to distinguish SAH from BI during the acute phase of cerebrovascular event in the emergency department.

Transient focal increase in perihematomal glucose metabolism after acute human intracerebral hemorrhage

BACKGROUND AND PURPOSE

Progressive perihematomal cell death over 3 to 4 days has been described after experimental intracerebral hemorrhage (ICH). We investigated whether progressive perihematomal damage occurs in human subjects by measuring relative changes in regional cerebral glucose metabolism with (18)F-fluorordeoxyglucose (FDG) positron emission tomography at multiple time points during the first week after ICH.

METHODS

Thirteen subjects with a median hematoma volume of 22 cm(3) were studied 1.0+/-0.3, 2.9+/-0.8, and 6.7+/-1.6 days after ICH. Normalized mean counts in 5 concentric annular 2-mm-thick perihematomal volumes-of-interest (VOIs) were compared to the initial study. Next, automated searches with 0.5 to 5.0 mL spherical VOIs identified maximum focal changes in normalized counts compared to the initial study.

RESULTS

No annular or focal decrease in perihematomal FDG uptake developed. Instead, FDG uptake significantly increased at session #2 in the first 3 2-mm annular VOIs (9.2%+/-14.2, 7.8%+/-11.3, 5.9%+/-9.0), returning to baseline at session #3. The VOI search identified focal regions of increased perihematomal FDG uptake relative to the contralateral control hemispheres in 6 subjects, which accounted for the annular increase.

CONCLUSIONS

Perihematomal glucose metabolism increased transiently in a subset of patients 2 to 4 days after acute ICH. These transient focal increases in glucose metabolism occurring in the brain after acute ICH demonstrate that there are ongoing processes in response to injury that last for days. Although further studies are needed to elucidate their pathophysiology, these processes may be indicative of a prolonged window for intervention to improve neurological outcome.

Guidelines for the Early Management of Adults With Ischemic Stroke

Purpose— Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

Methods— Members of the panel were appointed by the American Heart Association Stroke Council’s Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council’s Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

Results— Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

Inflammation after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating clinical event without effective therapies. Increasing evidence suggests that inflammatory mechanisms are involved in the progression of ICH-induced brain injury. Inflammation is mediated by cellular components, such as leukocytes and microglia, and molecular components, including prostaglandins, chemokines, cytokines, extracellular proteases, and reactive oxygen species. Better understanding of the role of the ICH-induced inflammatory response and its potential for modulation might have profound implications for patient treatment. In this review, a summary of the available literature on the inflammatory responses after ICH is presented along with discussion of some of the emerging opportunities for potential therapeutic strategies. In the near future, additional strategies that target inflammation could offer exciting new promise in the therapeutic approach to ICH.

Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: the American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists

PURPOSE

Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

METHODS

Members of the panel were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council's Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

RESULTS

Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

Ion channels involved in stroke

Ion channels are membrane proteins that flicker open and shut to regulate the flow of ions down their electrochemical gradient across the membrane and consequently regulate cellular excitability. Every living cell expresses ion channels, as they are critical life-sustaining proteins. Ion channels are generally either activated by voltage or by ligand interaction. For each group of ion channels the channels' molecular biology and biophysics will be introduced and the pharmacology of that group of channels will be reviewed. The in vitro and in vivo literature will be reviewed and, for ion channel groups in which clinical trials have been conducted, the efficacy and therapeutic potential of the neuroprotective compounds will be reviewed. A large part of this article will deal with glutamate receptors, focusing specifically on N-methyl-D-aspartate (NMDA) receptors. Although the outcome of clinical trials for NMDA receptor antagonists as therapeutics for acute stroke is disappointing, the culmination of these failed trials was preceded by a decade of efforts to develop these agents. Sodium and calcium channel antagonists will be reviewed and the newly emerging efforts to develop therapeutics targeting potassium channels will be discussed. The future development of stroke therapeutics targeting ion channels will be discussed in the context of the failures of the last decade in hopes that this decade will yield successful stroke therapeutics.

Stroke--acute interventions

The reduction of blood flow to parts of the brain is the cause of ischemic stroke leading to functional deficits and, if prolonged, to irreversible neurological and morphological defects. The fast reperfusion, therefore is the most important therapeutic strategy and was proven to be effective in clinical trials. Steps to intervene with secondary biochemical, molecular, or inflammatory disturbances were not successful so far. Since direct therapeutic interventions are limited, the general management of the stroke victim is of utmost importance--and was shown to be most successful in dedicated stroke units. Acute therapeutic interventions in ischemic stroke can only be successful as long as tissue in the area of the ischemic compromise is still viable. The area of irreversible damage can be identified and distinguished from the penumbral zone, i.e., tissue with impaired function but preserved morphology by functional imaging modalities, like positron emission tomography (PET) or perfusion-(PW) and diffusion-weighted (DW) magnetic resonance imaging (MRI). In such studies it was demonstrated that a large portion of the final infarct is irreversibly affected in the first few hours in many patients. A considerable tissue volume is viable but critically hypoperfused; a smaller portion of the final infarct is sufficiently perfused and in this area secondary and delayed biochemical and molecular mechanisms contribute to the damage. Based on this concept the improvement of perfusion within the time window of opportunity must be the primary goal in treatment of ischemic stroke, and neuroprotective and other strategies can only play a supportive and additive role. That this is the case can be seen from the results of many controlled therapeutic trials, in which up to now only thrombolytic therapy with a 3 h time window for systemic and a 6 h time window for intraarterial application proved its efficacy, whereas all trials with neuroprotective, anti-inflammatory or anti-apoptotic strategies failed. Since the direct treatment strategies are limited the acute management of stroke victims is of utmost importance: This can be achieved optimally in dedicated stroke units in which the outcome was significantly improved over the regular care. It is still to be investigated if invasive strategies--e.g., craniectomy and hypothermia--or the combination of reperfusion and neuroprotective therapy can improve the outcome after ischemic stroke.

Imaging in cerebrovascular disease

Various functional imaging modalities can be applied in acute ischaemic stroke to identify functionally impaired, but morphologically preserved tissue (i.e. the penumbra), and to distinguish it from irreversibly damaged tissue. Flow thresholds for irreversible tissue destruction resulting in functional impairment, as determined by positron emission tomography, perfusion and diffusion-weighted magnetic resonance imaging, single-photon computed tomography and xenon computed tomography, were comparable and ranged between 5 and 12 ml/100 g per min for the lower and 14 and 22 ml/100 g per min for the upper limit of penumbra. These imaging modalities help to select patients for thrombolytic therapy and provide evidence for the effect of this treatment on critically perfused tissue. They can also serve as surrogate markers in the evaluation of therapeutic efficacy. Further progress in interventional neuroradiology has been achieved with intra-arterial thrombolysis, which has become a treatment option beyond the 3-h therapeutic window in acute ischaemic stroke. Angioplasty and stenting of stenosis of arteries that supply the brain with blood have reached a point in their development at which a randomized trial to compare these treatments with vascular surgery is warranted.

Intracortical hemorrhage injury in rats : relationship between blood fractions and brain cell death

BACKGROUND AND PURPOSE

Intracerebral hemorrhage is associated with stroke and head trauma. The purposes of this study were to investigate the effect of intracortical injections of autologous whole blood and blood components on inflammatory cell infiltration and brain cell death and to determine if nonhemorrhagic lesions differ in these respects.

METHODS

Eighty-seven adult rats were subjected to intracortical injections of autologous whole blood or allogeneic plasma, erythrocytes, leukocytes, "activated" leukocytes, and serum. Injections of saline or mineral oil were controls. Blood injections were compared with cortical freeze injury and pial devascularization. Rats were perfusion-fixed 48 hours after injection or lesioning. Eosinophilic neurons, TUNEL-positive cells, brain damage area, infiltrating neutrophils, and CD8a-immunoreactive lymphocytes were quantified.

RESULTS

Damage area, dying cells, and inflammatory infiltrate were significantly greater after autologous whole blood, leukocyte, and "activated" leukocyte injections than injection of other fractions.

CONCLUSIONS

These results suggest that extravasated whole blood causes a greater degree of cortical cell death and inflammation than ischemic lesions of similar size. Leukocytes "activated" by systemic illness might exacerbate the injury. Secondary hemorrhagic phenomena suggest that the harmful effect is directed toward both brain cells and the vasculature. Further studies are required to delineate the mechanism(s).

Results in 95 hemorrhagic stroke patients included in CLASS, a controlled trial of clomethiazole versus placebo in acute stroke patients

BACKGROUND AND PURPOSE

Clomethiazole is a neuroprotective drug that enhances gamma-aminobutyrate type A (GABA(A)) receptor activity. Its efficacy and safety were tested in the CLomethiazole Acute Stroke Study (CLASS). The protocol allowed a CT scan to be done after randomization but within 7 days of stroke onset to minimize delays before start of treatment. Ninety-five of the 1360 patients randomized were diagnosed as having intracranial hemorrhage rather than ischemic stroke. Safety results for clomethiazole compared with placebo in this group are reported.

METHODS

The study included patients with a clinical diagnosis of acute hemispheric cerebral infarction. Treatment was a 24-hour intravenous infusion of 75 mg/kg clomethiazole or placebo. Patients with intracranial hemorrhage discovered on a postrandomization CT were withdrawn from study treatment if treatment was ongoing, and all patients were followed up to 90 days.

RESULTS

Ninety-four patients received treatment, 47 in each group. The hemorrhage was classified as intracerebral in 89 patients (94%). Mortality at 90 days was 19.1% in the clomethiazole group and 23.4% in the placebo group. Sedation was the most common adverse event, occurring at a higher incidence in clomethiazole-treated patients (clomethiazole 53%, placebo 17%), followed by rhinitis and coughing. The incidence and pattern of serious adverse events was similar between the treatment groups. The percentage of patients reaching relative functional independence on the Barthel Index (score >/=60) at 90 days was 59.6% in the clomethiazole group and 53.2% in the placebo group.

CONCLUSIONS

Clomethiazole appears safe to administer to hemorrhagic stroke patients compared with placebo. These results would obviate the need for a CT scan before therapy is initiated in acute stroke. The safety of clomethiazole in hemorrhagic stroke patients will be further evaluated in a prospective study that is under way in North America.