Minimally invasive procedures for evacuation of intracerebral hemorrhage reduces perihematomal glutamate content, blood-brain barrier permeability and brain edema in rabbits

The impact of time to evacuation on outcomes in endoscopic surgery for supratentorial spontaneous intracerebral hemorrhage: a single-center retrospective study

Supratentorial spontaneous intracerebral hemorrhage (SICH) can be treated with endoscopic surgery, but the optimal timing remains uncertain. We retrospectively analyzed data from 46 patients who underwent endoscopic surgery for supratentorial SICH. We examined the relationship between time to evacuation and functional outcome at 3 months, adjusting for prognostic factors. Surgical outcomes and complications were compared between patients with early (≤ 12 h) or late (> 12 h) evacuation. Median time to evacuation was 12 h, and the rate of unfavorable outcome (modified Rankin Scale > 3 at 3 months) was 32.6%. Longer time to evacuation was independently associated with unfavorable outcome (odds ratio per hour delay: 1.26). Late evacuation carried a 7.25-fold higher risk of unfavorable outcome compared to early evacuation. This association held across subgroups based on hematoma volume, location, and intraventricular extension (P for interaction > 0.05). Patients with late evacuation had fewer spot signs (24% vs. 4.8%, P = 0.035) and markers of hemorrhagic expansion (36% vs. 9.5%, P = 0.018), longer neurosurgical intensive care unit (NSICU) stay (3.2 vs. 1.9 days, P = 0.011) and hospital stay (15.7 vs. 11.9 days, P = 0.014), and higher 30-day mortality (28.6 vs. 4%, P = 0.036) and complication rates (57.1% vs. 28.0%, P = 0.023). This study suggests a potential association between early endoscopic evacuation of supratentorial SICH and improved functional outcomes, lower 30-day mortality and reduced complications. The need for timely intervention in managing supratentorial SICH is highlighted, yet further validation through multi-center prospective studies is essential to substantiate these findings and provide a higher level of evidence.

Minimally invasive intracerebral hemorrhage evacuation: A bibliometric analysis of current research trends

OBJECTIVE

Intracerebral hemorrhage (ICH) is associated with significant morbidity and mortality. Randomized clinical trials focusing on minimally invasive surgery (MIS) for ICH evacuation have suggested a potential benefit regarding mortality but results remain unclear regarding impact on functional outcome. This study presents a bibliometric analysis investigating the current trends in the literature on MIS for ICH.

METHODS

Using the Scopus collection database, a search was performed to identify literature that discussed MIS for ICH from 2000 to 2021. Primary research articles were included in this study. Reviews and book chapters were excluded. Analysis and visualization of the included literature were completed with VOSviewer.

RESULTS

A total of 278 articles were identified. An upward trend in publications began in 2008, with the most publications in 2021 (36) followed by 2020 (25). The most citations occurred in 2013 (1192). The h-index, i-10 and i-100 were 37, 79 and 6 respectively. For the top 100 most cited studies, the mean citation count was 45.55 with a range of 6-760. The highest-producing institutions of MIS for ICH literature were Johns Hopkins University (31, 15 %), University of Chicago with (21, 10 %), Guiyang Medical College (17, 8 %), and Icahn School of Medicine at Mount Sinai (15, 7 %). Keyword analysis revealed four major avenues: 1) medication enhancement of clot removal, 2) minimally invasive devices such as endoscopes, 3) craniotomy approach, and 4) physiology of clot removal.

CONCLUSIONS

The literature on MIS for ICH has been expanding since 2008. Key topics include thrombolysis, device innovation, and surgical approach.

Association between minimally invasive surgery and late seizures in patients with intracerebral hemorrhage: A propensity score matching study

Purpose

The association between minimally invasive surgery (MIS) for hematoma evacuation and late seizures after intracerebral hemorrhage (ICH) remains uncertain. We aimed to investigate whether MIS increases the risk of late seizures after ICH and identify the risk factors for late seizures in this patient subgroup.

Methods

We retrospectively included consecutive inpatients diagnosed with ICH at two tertiary hospitals in China. The subjects were divided into the MIS group (ICH patients who received MIS including hematoma aspiration and thrombolysis) and conservative treatment group (ICH patients who received conservative medication). Propensity score matching was performed to balance possible risk factors for late seizures between the MIS and conservative treatment groups. Before and after matching, between-group comparisons of the incidence of late seizures were performed between the MIS and conservative treatment groups. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for late seizures in MIS-treated patients.

Results

A total of 241 and 1,689 patients were eligible for the MIS and conservative treatment groups, respectively. After matching, 161 ICH patients from the MIS group were successfully matched with 161 ICH patients from the conservative treatment group (1:1). Significant differences (p < 0.001) were found between the MIS group (31/241, 12.9%) and conservative treatment group (69/1689, 4.1%) in the incidence of late seizures before matching. However, after matching, no significant differences (p = 0.854) were found between the MIS group (17/161, 10.6%) and conservative treatment group (16/161, 9.9%). Multivariate logistic regression analysis revealed that cortical involvement (OR = 2.547; 95% CI = 1.137-5.705; p value = 0.023) and higher National Institutes of Health Stroke Scale (NIHSS) scores (OR = 1.050; 95% CI = 1.008-1.094; p value = 0.019) were independent risk factors for late seizures.

Conclusion

Our study revealed that receiving MIS did not increase the incidence of late seizures after ICH. Additionally, cortical involvement and NIHSS scores were independent risk factors for late seizures in MIS-treated patients.

Secondary Brain Injury by Oxidative Stress After Cerebral Hemorrhage: Recent Advances

Intracerebral hemorrhage (ICH) is a clinical syndrome in which blood accumulates in the brain parenchyma because of a nontraumatic rupture of a blood vessel. Because of its high morbidity and mortality rate and the lack of effective therapy, the treatment of ICH has become a hot research topic. Meanwhile, Oxidative stress is one of the main causes of secondary brain injury(SBI) after ICH. Therefore, there is a need for an in-depth study of oxidative stress after ICH. This review will discuss the pathway and effects of oxidative stress after ICH and its relationship with inflammation and autophagy, as well as the current antioxidant therapy for ICH with a view to deriving better therapeutic tools or targets for ICH.

Minimally Invasive Surgery for ICH Evacuation Combined With Deferoxamine Treatment Increased Perihematomal Claudin-5 and ZO-1 Expression Levels and Decreased BBB Permeability in Rabbits

Objective

To investigate the role of minimally invasive surgery (MIS) in intracerebral hemorrhage (ICH) evacuation combined with deferoxamine (DFX) treatment on perihematomal tight junction protein (claudin-5 and ZO-1) expression levels and blood-brain barrier (BBB) permeability in rabbits.

Methods

We randomly assigned 65 male rabbits (weight: 1.9–2.6 kg) to a normal control group (NC group, 13 rabbits), hemorrhage model group (HM group, 13), DFX treatment group (DFX group, 13 rabbits), MIS group (MIS group, 13 rabbits), or MIS combined with DFX treatment group (MIS + DFX group, 13 rabbits). ICH was established in all of the groups except the NC group. MIS was performed to evacuate the hematoma 6 h after the ICH model was created in the MIS and MIS + DFX groups. The DFX and MIS + DFX groups were treated with DFX (100 mg/kg, dissolved in 2 mL of 0.9% saline solution, administered intramuscularly) at 2 h, and then every 12 h for 7 d. The same dose of 0.9% saline solution was administered to the NC, HM, and MIS groups at the same time points. Sixty-five rabbits were divided into 5 groups, and 13 rabbits in each group. Neurological deficit (i.e., Purdy's score) was recorded in all rabbits before euthanasia (N total = 65). In each group, 2 rabbits were used for iron concentration measurement (N total = 10), 2 rabbits were used for brain water content measurement (N total = 10), 3 rabbits were used for BBB permeability measurement (N total = 15), 3 rabbits were used for claudin-5, ZO-1 expression detection by Western Blotting (N total = 15), and 3 rabbits were used for claudin-5, ZO-1 mRNA detection by real-time PCR (N total = 15). On day 7, the rabbits were sacrificed and the perihematomal brain tissue was harvested to test the iron concentration, brain water content (BWC), tight junction proteins (claudin-5 and ZO-1) expression, and BBB permeability.

Results

Purdy's score, iron concentration, and BWC were lower in the MIS and MIS + DFX groups compared to the HM and DFX groups. The MIS + DFX group showed a significant decrease in these indicators. The use of MIS to evacuate the hematoma led to increased expression levels of claudin-5 and ZO-1, as well as decreased BBB permeability. The MIS + DFX group exhibited a remarkable increase in claudin-5 and ZO-1 expression levels and a significant decrease in BBB permeability.

Conclusions

MIS combined with DFX treatment could increase the expression levels of perihematomal tight junction proteins (claudin-5 and ZO-1) expression, reduce BBB permeability, and improve the neurological function. MIS combined with DFX treatment may also prevent secondary brain damage following ICH.

Activating PPARγ Increases NQO1 and γ-GCS Expression via Nrf2 in Thrombin-activated Microglia

The present study aimed to explore the molecular mechanisms underlying the increase of nicotinamide adenine dinucleotide phosphate:quinine oxidoreductase 1 (NQO1) and γ-glutamylcysteine synthetase (γ-GCS) in brain tissues after intracerebral hemorrhage (ICH). The microglial cells obtained from newborn rats were cultured and then randomly divided into the normal control group (NC group), model control group (MC group), rosiglitazone (RSG) intervention group (RSG group), retinoic-acid intervention group (RSG+RA group), and sulforaphane group (RSG+SF group). The expression levels of NQO1, γ-GCS, and nuclear factor E2-related factor 2 (Nrf2) were measured by real-time polymerase chain reaction (RT-PCR) and Western blotting, respectively. The results showed that the levels of NQO1, γ-GCS and Nrf2 were significantly increased in the MC group and the RSG group as compared with those in the NC group (P<0.01). They were found to be markedly decreased in the RSG+RA group and increased in the RSG+SF group when compared with those in the MC group or the RSG group (P<0.01). The RSG+SF group displayed the highest levels of NQO1, γ-GCS, and Nrf2 among the five groups. In conclusion, a medium dose of RSG increased the anti-oxidative ability of thrombin-activated microglia by increasing the expression of NQO1 and γ-GCS. The molecular mechanisms underlying the increase of NQO1 and γ-GCS in thrombin-activated microglia may be associated with the activation of Nrf2.

Stereotactic Catheter Drainage Versus Conventional Craniotomy for Severe Spontaneous Intracerebral Hemorrhage in the Basal Ganglia

Intracerebral hemorrhage (ICH) is one of the most devastating forms of cerebrovascular pathology. However, its treatment remains a matter of debate among neurosurgeons and neurologists. The study was to explore the efficacy of minimally invasive surgery (stereotactic catheter drainage, SCD) for patients with severe intracerebral hemorrhage (Glasgow Coma Scale, GCS) score ≤ 8 and hematoma volume ≥ 30 cm3) and to determine predisposing factors for good clinical outcome. A total of 75 patients with severe ICH were included in this retrospective study. Patients were assigned to the SCD group (n=38) or the conventional craniotomy group (n=37). Patients were followed up for 12 months postoperatively, and their clinical parameters were compared. During the operation, the SCD group exhibited a lower bleeding volume (p<0.001) and shorter operating time (p<0.001) than the conventional craniotomy group. For postoperative efficacy, the rates of pneumonia and tracheotomy were lower (p=0.002 and p=0.027, respectively), and the duration of hospital and neurosurgery intensive care unit (NSICU) in days were significantly shorter in the SCD group (p=0.046 and p=0.047, respectively). Furthermore, patients in the SCD group showed improved modified Rankin Scale (mRS) scores at discharge (p<0.018) and at 12-month follow up (p<0.001). Predisposing factors for good clinical outcomes were hematoma volume (<50 cm3, 95% confidence interval (CI): 1.043–1.956, p<0.046), initial GCS score (>6, 95% CI: 3.248–187.466, p<0.001), hypertension (none, 95% CI: 1.440–2.922, p<0.001), and treatment modality (SCD, 95% CI: 1.422–3.226, p<0.001). Taken together, SCD surgery is safe and effective in patients with severe ICH and has fewer complications and better clinical outcomes than conventional craniotomy.

Rosiglitazone pretreatment influences thrombin-induced anti-oxidative action via activating NQO1and γ-GCS in rat microglial cells

Objective To explore the molecular mechanism involved in rosiglitazone against secondary brain damage caused by cerebral hemorrhage, we pretreated thrombin-induced microglial cells by rosiglitazone and then investigated its effect on antioxidant-related genes NQO1and γ-GCS expression change. Methods Primary microglial cells were obtained from the brain tissue of newborn Sprague-Dawley (SD) rats and were randomly divided into three groups: the normal (control), thrombin stimulation (TH), thrombin-treated plus rosiglitazone (TH+RGZ). The expression of NQO1and γ-GCS was measured by immunocytochemistry, real-time PCR, and western blot analysis. Results The immunocytochemistry showed that the number of NQO1and γ-GCS stained cells in TH and TH+RGZ group increased compared to the control group. In addition, the expression of NQO1 and γ-GCS in TH+RGZ group remarkably increased in mRNA and protein level compared to TH only group (p < 0.01). Conclusion Rosiglitazone can increase thrombin-induced microglia anti-oxidative ability by increasing NQO1and γ-GCS expression, which can effectively reduce secondary injury after cerebral hemorrhage.

Rosiglitazone Infusion Therapy Following Minimally Invasive Surgery for Intracranial Hemorrhage Evacuation Decreased Perihematomal Glutamate Content and Blood-Brain Barrier Permeability in Rabbits

OBJECTIVE

To observe effects of rosiglitazone (RSG) infusion therapy on perihematomal peroxisome-proliferator-activated receptor gamma (PPARγ), glutamate, blood-brain barrier (BBB) permeability, and brain edema.

METHODS

Fifty male rabbits (2.8-3.4 kg) were randomly assigned to a normal control (NC) group, model control (MC) group, RSG group, minimally invasive surgery (MIS) group, or MIS and RSG (MIS+RSG) group. Intracranial hemorrhage was induced in all rabbits except for the NC group. MIS procedures were performed to evacuate the intracranial hemorrhage 6 hours after the intracranial hemorrhage model was prepared successfully. The animals were sacrificed on day 7, and the perihematomal brain tissue was obtained to determine PPARγ, glutamate, and BBB permeability.

RESULTS

Compared with the MC group, the MIS group displayed a remarkable decrease in PPARγ, glutamate, and BBB permeability. The RSG group showed similar results in glutamate level and BBB permeability but a significant increase in PPARγ. The MIS+RSG group displayed an increase in PPARγ and a more significant decrease in glutamate, BBB permeability, and neurologicl deficit scores compared with the other groups.

CONCLUSIONS

Performing MIS followed by RSG infusion therapy might increase PPARγ expression and might be more efficacious for reducing glutamate level and BBB permeability and improving neurologic function than MIS or RSG therapy used alone.

Quantitative assessment on blood-brain barrier permeability of acute spontaneous intracerebral hemorrhage in basal ganglia: a CT perfusion study

PURPOSE

Blood-brain barrier (BBB) damage aggravates perihematomal edema, and edema volume predicts prognosis independently. But the BBB permeability at the late stage of acute intracerebral hemorrhage (ICH) patients is uncertain. We aimed to assess the BBB permeability of spontaneous basal ganglia ICH using computed tomographic perfusion (CTP) and investigates its relationship with hematoma and perihematomal edema volume.

METHODS

We performed CTP on 54 consecutive ICH patients within 24 to 72 h after symptom onset. Permeability-surface area product (PS) derived from CTP imaging was measured in hematoma, "high-PS spot," perihematoma, normal-appearing, hemispheric, and contralateral regions. Hematoma and edema volumes were calculated from non-contrast CT.

RESULTS

"High-PS spot" and perihematoma regions had higher PS than the contralateral regions (p < 0.001). Hematoma PS was lower than that in the contralateral regions (p < 0.001). Perihematoma PS of the large-hematoma group was higher than that of the small-hematoma group (p = 0.011). Perihematomal edema volume correlated positively with hematoma volume (β = 0.864, p < 0.001) and perihematoma PS (β = 0.478, p < 0.001). Perihematoma PS correlated positively with hematoma volume (β = 0.373, p = 0.005).

CONCLUSIONS

Locally elevated perihematoma PS was found in most spontaneous basal ganglia ICH patients within 24 to 72 h after symptom onset. Perihematoma PS was higher in larger hematomas and was associated with larger edema volume. At this period, BBB leakage is likely to be an important factor in edema formation.

Minimally invasive surgery for ICH evacuation followed by rosiglitazone infusion therapy increased perihematomal PPARγ expression and improved neurological outcomes in rabbits

OBJECTIVES

To observe the effects of minimally invasive surgery (MIS) for intracerebral hematoma (ICH) evacuation followed by rosiglitazone infusion therapy on peroxisome proliferator-activated receptor-gamma (PPARγ), blood-brain barrier (BBB) permeability, and neurological function.

METHODS

A total of 75 male rabbits (2.8-3.4 kg) were randomly assigned to a normal control group (NC group), a model control group (MC group), a rosiglitazone group (RSG group), a minimally invasive treatment group (MIS group) or a MIS combined with rosiglitazone group (MIS+RSG group). ICH was induced in all of the animals except for those in the NC group. The rosiglitazone was infused into the hematoma area in the RSG group and the MIS+RSG group. A MIS was performed to evacuate the ICH 6 h after the successful preparation of the ICH model in the MIS group and the MIS+RSG group. Each group included 15 rabbits and was divided equally into 3 subgroups (each subgroup included 5 rabbits that were killed on day 1, day 3, or day 7). Neurological deficit scores were determined, and the perihematomal brain tissue was removed to determine the PPARγ level and BBB permeability.

RESULTS

Neurological deficit scores, perihematomal PPARγ levels, and BBB permeability were all significantly increased in the MC group compared to the NC group. Performing the MIS alone to evacuate the ICH resulted in a marked decrease in these indices. The RSG used alone increased PPARγ levels and decreased BBB disruption. The MIS+RSG group displayed a marked increase in PPARγ levels and a more significant decrease in BBB permeability and neurological deficit scores.

CONCLUSIONS

Performing MIS followed by PPARγ agonist infusion therapy is more efficacious for reducing secondary damage to the brain and improving neurological function.

Oxidative Stress in Intracerebral Hemorrhage: Sources, Mechanisms, and Therapeutic Targets

Intracerebral hemorrhage (ICH) is associated with the highest mortality and morbidity despite only constituting approximately 10–15% of all strokes. Complex underlying mechanisms consisting of cytotoxic, excitotoxic, and inflammatory effects of intraparenchymal blood are responsible for its highly damaging effects. Oxidative stress (OS) also plays an important role in brain injury after ICH but attracts less attention than other factors. Increasing evidence has demonstrated that the metabolite axis of hemoglobin-heme-iron is the key contributor to oxidative brain damage after ICH, although other factors, such as neuroinflammation and prooxidases, are involved. This review will discuss the sources, possible molecular mechanisms, and potential therapeutic targets of OS in ICH.

Blood glutamate grabbing does not reduce the hematoma in an intracerebral hemorrhage model but it is a safe excitotoxic treatment modality

Recent studies have shown that blood glutamate grabbing is an effective strategy to reduce the excitotoxic effect of extracellular glutamate released during ischemic brain injury. The purpose of the study was to investigate the effect of two of the most efficient blood glutamate grabbers (oxaloacetate and recombinant glutamate oxaloacetate transaminase 1: rGOT1) in a rat model of intracerebral hemorrhage (ICH). Intracerebral hemorrhage was produced by injecting collagenase into the basal ganglia. Three treatment groups were developed: a control group treated with saline, a group treated with oxaloacetate, and a final group treated with human rGOT1. Treatments were given 1 hour after hemorrhage. Hematoma volume (analyzed by magnetic resonance imaging (MRI)), neurologic deficit, and blood glutamate and GOT levels were quantified over a period of 14 days after surgery. The results observed showed that the treatments used induced a significant reduction of blood glutamate levels; however, they did not reduce the hematoma, nor did they improve the neurologic deficit. In the present experimental study, we have shown that this novel therapeutic strategy is not effective in case of ICH pathology. More importantly, these findings suggest that blood glutamate grabbers are a safe treatment modality that can be given in cases of suspected ischemic stroke without previous neuroimaging.

Stereotactic-Guided Evacuation of Spontaneous Supratentorial Intracerebral Hemorrhage: Systematic Review and Meta-Analysis

BACKGROUND

Spontaneous intracerebral hemorrhage (SICH) has a high morbidity and mortality and places a huge significant economic burden on health care and social services. The role of surgery is still controversial as evidenced by wide variation internationally in management of SICH. Traditional surgery for SICH involved open craniotomy with hematoma evacuation. Using available evidence, this article assesses the efficacy of stereotactic-guided evacuation compared with medical treatment.

METHODS

A systematic review was performed comparing stereotactic-guided evacuation of SICH with conservative medical management. Eligible studies were identified using a text word search of an electronic journal database for randomized controlled trials. Extracted data outcomes were subjected to meta-analysis with a forest plot. Quality was assessed using Cochrane risk of bias analysis tools.

RESULTS

There were 5 studies with 740 patients. There was a nonsignificant reduction in odds ratio (OR) for death at the end of the follow-up period (OR = 0.74, 95% confidence interval = 0.45-1.21) with no significant heterogeneity. Nonsignificant benefits were observed for dependent survival (OR = 2.14, 95% confidence interval = 0.31-0.58). In the subgroup analysis, stereotactic evacuation showed improved outcomes in patients with hematoma volume <50 mL. In this review, the effectiveness of stereotactic evacuation plus subsequent thrombolysis was insignificant (OR = 1.34, 95% confidence interval = 0.57-3.12).

CONCLUSIONS

The outcome of patients who had stereotactic-guided evacuation of SICH was not better compared with patients who received medical treatment; however, there was a trend toward better quality of survival and chance of survival in the stereotactic-guided evacuation group. This study identified areas for further research.

Rosiglitazone infusion therapy following minimally invasive surgery for intracerebral hemorrhage evacuation decreases matrix metalloproteinase-9 and blood-brain barrier disruption in rabbits

Background

The objective of this study was to investigate the effects of Rosiglitazone (RSG) infusion therapy following minimally invasive surgery (MIS) for intracerebral hemorrhage(ICH) evacuation on perihematomal secondary brain damage as assessed by MMP-9 levels, blood–brain barrier (BBB) permeability and neurological function.

Methods

A total of 40 male rabbits (2.8–3.4 kg) was randomly assigned to a normal control group (NC group; 10 rabbits), a model control group (MC group; 10 rabbits), a minimally invasive treatment group (MIS group; 10 rabbits) or a combined MIS and RSG group (MIS + RSG group; 10 rabbits). ICH was induced in all the animals, except for the NC group. MIS was performed to evacuate ICH 6 hours after the successful preparation of the ICH model in the MIS and MIS + RSG groups. The animals in the MC group underwent the same procedures for ICH evacuation but without hematoma aspiration, and the NC group was subjected to sham surgical procedures. The neurological deficit scores (Purdy score) and ICH volumes were determined on days 1, 3 and 7. All of the animals were sacrificed on day 7, and the perihematomal brain tissue was removed to determine the levels of PPARγ, MMP-9, BBB permeability and brain water content (BWC).

Results

The Purdy score, perihematomal PPARγ levels, BBB permeability, and BWC were all significantly increased in the MC group compared to the NC group. After performing the MIS for evacuating the ICH, the Purdy score and the ICH volume were decreased on days 1, 3 and 7 compared to the MC group. A remarkable decrease in perihematomal levels of PPARγ, MMP-9, BBB permeability and BWC were observed. The MIS + RSG group displayed a remarkable increase in PPARγ as well as significant decrease in MMP-9, BBB permeability and BWC compared with the MIS group.

Conclusions

RSG infusion therapy following MIS for ICH treatment might be more efficacious for reducing the levels of MMP-9 and secondary brain damage than MIS therapy alone.

Early-stage minimally invasive procedures decrease perihematomal endothelin-1 levels and improve neurological functioning in a rabbit model of intracerebral hemorrhage

INTRODUCTION

To determine the effects of minimally invasive surgery (MIS) at various stages after intracerebral hemorrhage (ICH) on perihematomal endothelin (ET)-1 levels and neurological functioning.

METHODS

Sixty rabbits were randomly distributed into a model control group (MC group, 30 rabbits) or a MIS group (MI group, 30 rabbits). An ICH model was established in all animals. In the MI group, ICH was evacuated by MIS at 6, 12, 18, 24, and 48 hours (six rabbits at each time point) after the ICH was established. The animals in the MC group underwent the same procedures for ICH evacuation, but with a sham operation without hematoma aspiration. All the animals were sacrificed 7 days after the ICH was established. Neurological deficit scores were determined, and the perihematomal brain tissue was removed to determine the ET-1 levels, blood-brain barrier (BBB) permeability, and brain water content (BWC).

RESULTS

The neurological deficit scores, perihematomal ET-1 levels, BBB permeability, and BWC all decreased significantly in the MI group compared to the MC group. Performing the MIS for evacuating the ICH at 6 hours resulted in the most remarkable decreases in these indices, followed by a significant difference observed at 12 hours within the MI subgroups.

CONCLUSIONS

Performing MIS at 6-12 hours after ICH resulted in the most significant decreases in neurological deficit scores, ET-1 levels, BBB permeability, and brain edema. The optimal time window for performing MIS for ICH evacuation might be within 6-12 hours after hemorrhage.

Effects of minimally invasive procedures for evacuation of intracerebral hematoma in early stages on MMP-9 and BBB permeability in rabbits

BACKGROUND

The effects of performing a minimally invasive procedure at different stages after intracerebral hemorrhage on perihematomal MMP-9 expression and blood-brain barrier (BBB) permeability were evaluated.

METHODS

Sixty rabbits were randomly distributed into a model control group (MC group, 30 rabbits) or a minimally invasive group (MI group, 30 rabbits). A model of intracerebral hemorrhage was established in the MC and MI group. In the MI group, the intracerebral hematoma was evacuated by stereotactic minimally invasive procedures over 6 hours (6 rabbits), 12 hours (6 rabbits), 18 hours (6 rabbits) 24 hours or 48 hours (6 rabbits) following successful induction of intracerebral hemorrhage. The same procedure was performed in the MC group at the same time point but without evacuating the hematoma. All the animals were sacrificed within two weeks after the hematoma was surgically evacuated. A neurological deficit score was determined, and the perihematomal MMP-9 level and the BBB permeability were measured.

RESULTS

The neurological deficit score, perihematomal MMP-9 level and BBB permeability of the MI group decreased significantly compared to the MC group. Performing the MI procedure 6-12 h after intracerebral hemorrhage showed the most favorable outcome.

CONCLUSIONS

Regarding the pathophysiological changes surrounding the hematoma, the optimal time window of performing MI procedures for the intracerebral hematoma evacuation might be within 6-12 h after hemorrhage.

Progress in translational research on intracerebral hemorrhage: is there an end in sight?

Intracerebral hemorrhage (ICH) is a common and often fatal stroke subtype for which specific therapies and treatments remain elusive. To address this, many recent experimental and translational studies of ICH have been conducted, and these have led to several ongoing clinical trials. This review focuses on the progress of translational studies of ICH including those of the underlying causes and natural history of ICH, animal models of the condition, and effects of ICH on the immune and cardiac systems, among others. Current and potential clinical trials also are discussed for both ICH alone and with intraventricular extension.

Perihematomal glutamate level is associated with the blood-brain barrier disruption in a rabbit model of intracerebral hemorrhage

Objective

To observe the relationship between the perihematomal glutamate levels and the blood–brain barrier (BBB) permeability in a rabbit model of intracerebral hemorrhage (ICH).

Methods

Seventy-two rabbits were randomly divided into an intracerebral hemorrhage (ICH) model group and a normal control (NC) group, and each group of 36 rabbits was subsequently divided into 6, 12, 18, 24, 48 and 72 h groups (n = 6 each). An ICH model was induced by stereotactic injection of autologous, arterial, non-anticoagulated blood into rabbit basal ganglia. The same procedures were performed in the NC group, but blood was not injected. The rabbits were sacrificed at specific time points after the experiment began depending on their group. Perihematomal brain tissues were collected to determine glutamate levels, BBB permeability and brain water content (BWC).

Results

All of the assessed parameters were increased 6 hour after blood infusion and continued to gradually increase, peaking at 48 hours. Differences were observed when ICH values were compared with those of the NC group (p < 0.05).

Conclusions

Perihematomal glutamate increased significantly after ICH. High levels of glutamate are closely associated with BBB disruption and the brain edema. Therefore, glutamate may play an important role in the pathogenesis of secondary brain injury after (ICH).

Magnetic resonance imaging profile of blood-brain barrier injury in patients with acute intracerebral hemorrhage

Background

Spontaneous intracerebral hemorrhage (ICH) is associated with blood–brain barrier (BBB) injury, which is a poorly understood factor in ICH pathogenesis, potentially contributing to edema formation and perihematomal tissue injury. We aimed to assess and quantify BBB permeability following human spontaneous ICH using dynamic contrast‐enhanced magnetic resonance imaging (DCE MRI). We also investigated whether hematoma size or location affected the amount of BBB leakage.

Methods and Results

Twenty‐five prospectively enrolled patients from the Diagnostic Accuracy of MRI in Spontaneous intracerebral Hemorrhage (DASH) study were examined using DCE MRI at 1 week after symptom onset. Contrast agent dynamics in the brain tissue and general tracer kinetic modeling were used to estimate the forward leakage rate (K^trans) in regions of interest (ROI) in and surrounding the hematoma and in contralateral mirror–image locations (control ROI). In all patients BBB permeability was significantly increased in the brain tissue immediately adjacent to the hematoma, that is, the hematoma rim, compared to the contralateral mirror ROI (P<0.0001). Large hematomas (>30 mL) had higher K^trans values than small hematomas (P<0.005). K^trans values of lobar hemorrhages were significantly higher than the K^trans values of deep hemorrhages (P<0.005), independent of hematoma volume. Higher K^trans values were associated with larger edema volumes.

Conclusions

BBB leakage in the brain tissue immediately bordering the hematoma can be measured and quantified by DCE MRI in human ICH. BBB leakage at 1 week is greater in larger hematomas as well as in hematomas in lobar locations and is associated with larger edema volumes.

Early stage minimally invasive procedures reduce perihematomal MMP-9 and blood-brain barrier disruption in a rabbit model of intracerebral hemorrhage

INTRODUCTION

The effects of performing a minimally invasive procedure at different stages after intracerebral hemorrhage (ICH) on perifocal MMP-9 expression and blood-brain barrier (BBB) permeability were evaluated.

METHODS

Thirty-six rabbits were randomly distributed into a normal control group (NC group, six rabbits), a model control group (MC group, six rabbits), and a minimally invasive group (MI group, 24 rabbits). A model of ICH was established in the MC and MI groups. In the MI group, the intracerebral hematoma was evacuated by stereotactic minimally invasive procedures over 6 hours (six rabbits), 12 hours (six rabbits), 18 hours (six rabbits), and 24 hours (six rabbits), following successful induction of ICH. All animals were sacrificed within 48 hours after the hematoma was surgically evacuated. A neurological deficit score was determined, and the perihematomal MMP-9 level and the BBB permeability were measured.

RESULTS

The neurological deficit score, the perihematomal MMP-9 level, and the BBB permeability of the MI group were decreased significantly compared with the MC group. Performing the MI procedure 6-12 hours after ICH showed the most significant decrease in MMP-9, BBB permeability, and neurological deficit score.

CONCLUSION

The optimal time window of performing MI procedures for the intracerebral hematoma evacuation might be within 6-12 hours after hemorrhage.

Minimally invasive surgery plus recombinant tissue-type plasminogen activator for intracerebral hemorrhage evacuation decreases perihematomal edema

BACKGROUND AND PURPOSE

Perihematomal edema (PHE) can worsen outcomes after intracerebral hemorrhage (ICH). Reports suggest that blood degradation products lead to PHE. We hypothesized that hematoma evacuation will reduce PHE volume and that treatment with recombinant tissue-type plasminogen activator (rt-PA) will not exacerbate it.

METHODS

Minimally invasive surgery and rt-PA in ICH evacuation (MISTIE) phase II tested safety and efficacy of hematoma evacuation after ICH. We conducted a semiautomated, computerized volumetric analysis on computed tomography to assess impact of hematoma removal on PHE and effects of rt-PA on PHE. Volumetric analyses were performed on baseline stability and end of treatment scans.

RESULTS

Seventy-nine surgical and 39 medical patients from minimally invasive surgery and rt-PA in ICH evacuation phase II (MISTIE II) were analyzed. Mean hematoma volume at end of treatment was 19.6±14.5 cm(3) for the surgical cohort and 40.7±13.9 cm(3) for the medical cohort (P<0.001). Edema volume at end of treatment was lower for the surgical cohort: 27.7±13.3 cm(3) than medical cohort: 41.7±14.6 cm(3) (P<0.001). Graded effect of clot removal on PHE was observed when patients with >65%, 20% to 65%, and <20% ICH removed were analyzed (P<0.001). Positive correlation between PHE reduction and percent of ICH removed was identified (ρ=0.658; P<0.001). In the surgical cohort, 69 patients underwent surgical aspiration and rt-PA, whereas 10 underwent surgical aspiration only. Both cohorts achieved similar clot reduction: surgical aspiration and rt-PA, 18.9±14.5 cm(3); and surgical aspiration only, 24.5±14.0 cm(3) (P=0.26). Edema at end of treatment in surgical aspiration and rt-PA was 28.1±13.8 cm(3) and 24.4±8.6 cm(3) in surgical aspiration only (P=0.41).

CONCLUSIONS

Hematoma evacuation is associated with significant reduction in PHE. Furthermore, PHE does not seem to be exacerbated by rt-PA, making such neurotoxic effects unlikely when the drug is delivered to intracranial clot.

Minimally invasive procedures for intracerebral hematoma evacuation in early stages decrease perihematomal glutamate level and improve neurological function in a rabbit model of ICH

INTRODUCTION

To observe the effects of performing a minimally invasive procedure at different stages after intracerebral hemorrhage (ICH) on perihematomal glutamate level and neurological function.

METHODS

Forty-eight rabbits were randomly placed into a model control group (MC group, 24 rabbits) or a minimally invasive group (MI group, 24 rabbits). An ICH model was established in all of the animals. In the MI group, the ICH was evacuated by minimally invasive procedures in 6h (6 rabbits), 12h (6 rabbits), 18h (6 rabbits) and 24h (6 rabbits) after the ICH model was successfully induced. All of the animals were sacrificed within 48h after the hematoma was evacuated by surgery. A neurological deficit score was determined, and the perihematomal glutamate level and the BBB permeability were measured.

RESULTS

The neurological deficit score, perihematomal glutamate level and BBB permeability of the MI group were decreased significantly compared with the MC group. Performing the minimally invasive procedures in 6-12 h after ICH showed the most significant decreases of the glutamate level, BBB permeability and neurological deficit score.

CONCLUSIONS

The optimal time window of performing the minimally invasive procedures for the intracerebral hematoma evacuation might be within 6-12 h after hemorrhage.

The pathophysiological time window study of performing minimally invasive procedures for the intracerebral hematoma evacuation in rabbit

The objective of this study was to observe the pathophysiological time window of performing minimally invasive procedures for the intracerebral hematoma evacuation. Thirty-six rabbits were randomly placed in either a normal control group (NC group, 6 rabbits), a model control group (MC group, 6 rabbits) or a minimally invasive group (MI group, 24 rabbits). A model of intracerebral hemorrhage (ICH) was established in the MC and MI groups. In the MI group, the intracerebral hematoma was evacuated by stereotactic minimally invasive procedures over 6h (6 rabbits), 12h (6 rabbits), 18 h (6 rabbits) and 24h (6 rabbits), following successful induction of ICH. All of the animals in each group were sacrificed 48 h after the successful induction of ICH. Perihematomal brain tissues were removed to determine the glutamate level, BBB permeability and brain water content (BWC). The perihematomal glutamate level, BBB permeability and the BWC in the MI group were significantly decreased compared with those of the MC group. Performing minimally invasive procedures for evacuation of ICH in 6h showed the most remarkable decrease of the glutamate level, BBB permeability and BWC, followed by a significant difference observed at 12h within the MI subgroups. Performing minimally invasive procedures in early stages after ICH for the hematoma evacuation could decrease the perihematomal glutamate level, BBB permeability and BWC significantly. The pathophysiological time window of minimally invasive procedures for hematoma evacuation might be 6-12h after hemorrhage.

Minimally invasive procedures reduce perihematomal endothelin-1 levels and the permeability of the BBB in a rabbit model of intracerebral hematoma

To observe the effects of minimally invasive procedures for the evacuation of intracerebral hematomas on perihematomal ET-1 expression and their correlation with blood-brain barrier (BBB) permeability. Forty-five rabbits (2.8-3.4 kg body weight) were randomly divided into a normal control group (NC group, 15 rabbits), a model control group (MC group, 15 rabbits) and a minimally invasive group (MI group, 15 rabbits). A model of intracerebral hemorrhage (ICH) was prepared in the MC and MI groups by infusing autologous arterial blood into the rabbits' brains; the same procedure was also performed in the NC group but without infusing blood into the rabbits' brains. The intracerebral hematomas were evacuated by a stereotactic procedure in the minimally invasive group 6 h after the model was established. The neurological functions, ET-1 expression and the perihematomal BBB permeability were determined and analyzed in all of the animals. The number of endothelial cells with ET-1-positive expression and the perihematomal BBB permeability significantly increased 1, 3, and 7 days after the ICH model was prepared successfully, as compared to the NC group. In the MI group, however, both measurements decreased markedly compared with the MC group at the same time point. A positive correlation between the number of endothelial cells with ET-1-positive expression and BBB permeability was observed. Increased BBB permeability might be associated with perihematomal ET-1 levels. Minimally invasive procedures for the evacuation of intracerebral hematomas could significantly decrease BBB permeability in perihematomal brain tissues, likely by reducing the production of ET-1.

Experimental intracerebral hemorrhage: avoiding pitfalls in translational research

Intracerebral hemorrhage (ICH) has the highest mortality of all stroke subtypes, yet treatments are mainly limited to supportive management, and surgery remains controversial. Despite significant advances in our understanding of ICH pathophysiology, we still lack preclinical models that accurately replicate the underlying mechanisms of injury. Current experimental ICH models (including autologous blood and collagenase injection) simulate different aspects of ICH-mediated injury but lack some features of the clinical condition. Newly developed models, notably hypertension- and oral anticoagulant therapy-associated ICH models, offer added benefits but further study is needed to fully validate them. Here, we describe and discuss current approaches to experimental ICH, with suggestions for changes in how this condition is studied in the laboratory. Although advances in imaging over the past few decades have allowed greater insight into clinical ICH, there remains an important role for experimental models in furthering our understanding of the basic pathophysiologic processes underlying ICH, provided limitations of animal models are borne in mind. Owing to differences in existing models and the failed translation of benefits in experimental ICH to clinical practice, putative neuroprotectants should be trialed in multiple models using both histological and functional outcomes until a more accurate model of ICH is developed.