Fibrinolysis therapy achieved with tissue plasminogen activator and aspiration of the liquefied clot after experimental intracerebral hemorrhage: rapid reduction in hematoma volume but intensification of delayed edema formation

Effectiveness of Intracerebral Hemorrhage Aspiration with Catheter Insertion: Impact on Hematoma Volume and Symptom Improvement

Background: Catheter insertion is the most commonly used method for treating intracerebral hemorrhage (ICH). Simultaneous hematoma aspiration allows for faster decompression than catheter insertion alone. Methods: Between March 2020 and Apri1 2024, 49 patients (25 men and 24 women) with ICH underwent ICH catheter insertion. Thirty-two patients (Group A) underwent intraoperative aspiration simultaneously with ICH catheter insertion. The other seventeen patients underwent catheter insertion alone (Group B). Four patients in Group A (12.5%) and two patients in Group B (11.8%) died within one month after surgery. Consequently, a total of 43 patients were included in the final analysis (Group A-1 vs. Group B-1). The Glasgow coma scale (GCS) score and muscle strength of the four extremities in both groups were compared 2 weeks later (first period) and on the date of discharge (second period). Patients in Group A-1 were discharged 5 days earlier than those in Group B-1. (average 49 ± 20 vs. 54 ± 31 days). Results: In Group A, the preoperative ICH volume was 66.2 ± 28.8 mL, and the median aspiration volume was 30 ± 19.6 mL. The preoperative ICH volume was 55.9 ± 22.2 mL in group B. Intraoperative ICH aspiration (Group A-1) significantly improved motor scores during the second period (p = 0.001). It also showed the trend toward improved GCS scores during the first period (p = 0.095) and the second period (p = 0.069). Conclusions: Compared to ICH catheter insertion alone, additional intraoperative ICH aspiration resulted in greater motor improvement at 7 weeks postoperatively (p = 0.004). It also showed a trend toward greater improvement in the GCS scores (p = 0.12).

O2L-001, an innovative thrombolytic to evacuate intracerebral haematoma

Intracerebral haemorrhage is an unmet medical need affecting more than 3 million people worldwide every year and leading to the formation of an intracerebral haematoma. Updated guidelines (2022) for the management of intracerebral haemorrhage patients recognize that minimally invasive approaches for the evacuation of supratentorial intracerebral haemorrhage have demonstrated reductions in mortality compared with medical management alone. However, improvement of functional outcome with a procedure involving thrombolytic therapy was neutral in the last large phase 3 clinical trial and requires a more effective and safer thrombolytic agent than those currently available. Here, we demonstrate that O2L-001 allows for the extended release of W253R/R275S recombinant tissue-type plasminogen activator (rtPA). A new rtPA variant, called optimized tPA (OptPA), offers improved efficacy for haematoma evacuation as well as improved safety. OptPA was produced in a Chinese hamster ovary cell line before purification, nanoprecipitation using the NANOp2Lysis® technological platform followed by suspension in a solution of 17% poloxamer 407 to obtain O2L-001. Plasmin generation assays were performed to demonstrate O2L-001 safety. Ex vivo haematoma models using human blood were used to demonstrate O2L-001 thrombolysis properties and efficacy. For the best translational significance, a clinical sized haematoma was used to ensure catheter placement and to allow administration of the thrombolytic agent into the core of the haematoma via a minimally invasive procedure. The capacity of OptPA to convert plasminogen into plasmin is strongly decreased compared to rtPA, thereby reducing potential bleeding events. However, a clot lysis assay showed that OptPA had the same fibrinolytic activity as rtPA. We demonstrated that long-term exposure to a thrombolytic agent was essential to achieve high thrombolysis efficacy. Indeed, 24 h continuous exposure to 0.1 µg/ml rtPA had similar efficacy than repeated short exposure to 30 µg/ml rtPA. This finding led to the development of O2L-001, allowing the extended release of OptPA in the first 6 h following injection. An ex vivo model using human blood was used to demonstrate O2L-001 efficacy. Interestingly, unlike rtPA, O2L-001 was able to induce the complete lysis of the 5 ml haematoma. In clinical sized haematomas (obtained from 30 ml of human blood), a single injection of O2L-001 at 1 mg/ml into the core of the haematoma led to a 44% increase in thrombolysis compared to rtPA. Taken together, these results demonstrate that O2L-001 provides new hope for haematoma evacuation and the treatment of patients with intracerebral haemorrhage.

Adherens, tight, and gap junctions in ependymal cells: A systematic review of their contribution to CSF-brain barrier

Introduction

The movement of fluids and solutes across the ependymal barrier, and their changes in physiologic and disease states are poorly understood. This gap in knowledge contributes strongly to treatment failures and complications in various neurological disorders.

Methods

We systematically searched and reviewed original research articles treating ependymal intercellular junctions on PubMed. Reviews, opinion papers, and abstracts were excluded. Research conducted on tissue samples, cell lines, CSF, and animal models was considered.

Results

A total of 45 novel articles treating tight, adherens and gap junctions of the ependyma were included in our review, spanning from 1960 to 2022. The findings of this review point toward a central and not yet fully characterized role of the ependymal lining ultrastructure in fluid flow interactions in the brain. In particular, tight junctions circumferentially line the apical equator of ependymal cells, changing between embryonal and adult life in several rodent models, shaping fluid and solute transit in this location. Further, adherens and gap junctions appear to have a pivotal role in several forms of congenital hydrocephalus.

Conclusions

These findings may provide an opportunity for medical management of CSF disorders, potentially allowing for tuning of CSF secretion and absorption. Beyond hydrocephalus, stroke, trauma, this information has relevance for metabolite clearance and drug delivery, with potential to affect many patients with a variety of neurological disorders. This critical look at intercellular junctions in ependyma and the surrounding interstitial spaces is meant to inspire future research on a central and rather unknown component of the CSF-brain interface.

Animal models for the study of intracranial hematomas (Review)

Intracranial hematomas (ICH) are a frequent condition in neurosurgical and neurological practices, with several mechanisms of primary and secondary injury. Experimental research has been fundamental for the understanding of the pathophysiology implicated with ICH and the development of therapeutic interventions. To date, a variety of different animal approaches have been described that consider, for example, the ICH evolutive phase, molecular implications and hemodynamic changes. Therefore, choosing a test protocol should consider the scope of each particular study. The present review summarized investigational protocols in experimental research on the subject of ICH. With this subject, injection of autologous blood or bacterial collagenase, inflation of intracranial balloon and avulsion of cerebral vessels were the models identified. Rodents (mice) and swine were the most frequent species used. These different models allowed improvements on the understanding of intracranial hypertension establishment, neuroinflammation, immunology, brain hemodynamics and served to the development of therapeutic strategies.

Dissolution Effect of Alteplase on Arterial Blood Clot Model of Hypertensive Intracerebral Hemorrhage Patients in vitro

Objective

To explore the dissolution effect of alteplase (rt-PA) on arterial blood clots of patients with hypertensive cerebral hemorrhage in vitro and analyze the optimal concentration and action time of rt-PA for intracranial hematomas.

Methods

The arterial blood of 35 patients with confirmed hypertensive cerebral hemorrhage were collected, centrifuged, and the serum was aspirated to prepare the blood clot model. The 0.125, 0.25, 0.5, 1, 2, and 3 mg t-PA, 20,000 U, and 40,000 U urokinase (u-PA) were taken for the corresponding blood clot for dissolution test. The blood clot volume and dissolution volume was measured at 0, 30, 60, 90, 120, and 150 min.

Results

Without intervention, the blood clot volume of men was higher than that of women at 0, 30, 60, and 90 min (P < 0.05). Without intervention, hematocrit (HCT) was correlated with blood clot volume and the correlation decreased with time. The 30, 60, and 90 min dissolution curves of each group showed an upward trend (P < 0.05), and the dissolution curves tended to be flat at 120 min and 150 min. The dissolution volume of.125 mg/3 ml, 0.25 mg/3 ml, 0.5 mg/3 ml rt-PA, 20,000 U, 40,000 U u-PA was higher than that of 1, 2, 3 mg/ml rt-PA (P < 0.05). The dissolution volume of.125 mg/3 ml, 0.25 mg/3 ml, 0.5 mg/3 ml rt-PA was not significantly different from 20,000 and 40,000 U u-PA (P > 0.05). Gender differences did not affect the effects of the above drugs.

Conclusion

In vitro, low-concentration rt-PA has a better dissolution effect, and it shows a time-dependent effect, reaching the highest effect in 90 min.

Upregulation of AQP4 Improves Blood-Brain Barrier Integrity and Perihematomal Edema Following Intracerebral Hemorrhage

In intracerebral hemorrhage (ICH), delayed secondary neural damages largely occur from perihematomal edema (PHE) resulting from the disruption of the blood-brain barrier (BBB). PHE is often considered the principal cause of morbidity and mortality in patients with ICH. Nevertheless, the main cellular mechanism as well as the specific BBB component involved in the formation of PHE after ICH remains elusive. Herein, we evaluated the role of AQP4, a water channel expressed on the astrocytes of the BBB, in the formation of PHE in ICH. The static and dynamic functions of the BBB were evaluated by analyzing the microstructure and leakage assay. Protein changes in the PHE lesion were analyzed and the control mechanism of AQP4 expression by reactive oxygen species was also investigated. Delayed PHE formation due to BBB disruption after ICH was confirmed by the decreased coverage of multiple BBB components and increased dynamic leakages. Microstructure assay showed that among the BBB components, AQP4 showed a markedly decreased expression in the PHE lesions. The decrease in AQP4 was due to microenvironmental ROS derived from the hemorrhage and was restored by treatment with ROS scavenger. AQP4-deficient mice had significantly larger PHE lesions and unfavorable survival outcomes compared with wild-type mice. Our data identify AQP4 as a specific BBB-modulating target for alleviating PHE in ICH. Further comprehensive studies are needed to form the preclinical basis for the use of AQP4 enhancers as BBB modulators for preventing delayed cerebral edema after ICH.

Intrahematomal Ultrasound Enhances RtPA-Fibrinolysis in a Porcine Model of Intracerebral Hemorrhage

Catheter-based ultrasound-thrombolysis has been successfully used in a small clinical trial in order to enhance recombinant tissue plasminogen activator (rtPA)-fibrinolysis, for the treatment of spontaneous intracerebral hemorrhages (ICHs). The aim of this study was to investigate the ultra-early effects of ultrasound on hematoma and the surrounding brain tissue in a porcine ICH-model. To achieve this, 21 pigs with a right frontal ICH were randomly assigned to four groups: (1) drainage (n = 3), (2) drainage + rtPA (n = 6), (3) drainage + ultrasound (n = 6), and (4) drainage + ultrasound + rtPA (n = 6). The hematoma volume assessment was performed using cranial MRI before and after the treatments. Subsequently, the brain sections were analyzed using HE-staining and immunohistochemistry. The combined treatment using rtPA and ultrasound led to a significantly higher hematoma reduction (62 ± 5%) compared to the other groups (Group 1: 2 ± 1%; Group 2: 30 ± 12%; Group 3: 18 ± 8% (p < 0.0001)). In all groups, the MRI revealed an increase in diffusion restriction but neither hyper- or hypoperfusion, nor perihematomal edema. HE stains showed perihematomal microhemorrhages were equally distributed in each group, while edema was more pronounced within the control group. Immunohistochemistry did not reveal any ultra-early side effects. The combined therapy of drainage, rtPA and ultrasound is a safe and effective technique for hematoma-reduction and protection of the perihematomal tissue in regard to ultra-early effects.

Relevance of Porcine Stroke Models to Bridge the Gap from Pre-Clinical Findings to Clinical Implementation

In the search of animal stroke models providing translational advantages for biomedical research, pigs are large mammals with interesting brain characteristics and wide social acceptance. Compared to rodents, pigs have human-like highly gyrencephalic brains. In addition, increasingly through phylogeny, animals have more sophisticated white matter connectivity; thus, ratios of white-to-gray matter in humans and pigs are higher than in rodents. Swine models provide the opportunity to study the effect of stroke with emphasis on white matter damage and neuroanatomical changes in connectivity, and their pathophysiological correlate. In addition, the subarachnoid space surrounding the swine brain resembles that of humans. This allows the accumulation of blood and clots in subarachnoid hemorrhage models mimicking the clinical condition. The clot accumulation has been reported to mediate pathological mechanisms known to contribute to infarct progression and final damage in stroke patients. Importantly, swine allows trustworthy tracking of brain damage evolution using the same non-invasive multimodal imaging sequences used in the clinical practice. Moreover, several models of comorbidities and pathologies usually found in stroke patients have recently been established in swine. We review here ischemic and hemorrhagic stroke models reported so far in pigs. The advantages and limitations of each model are also discussed.

Bedside Catheter Hematoma Evacuation in Vitamin K Antagonist-Related Intracerebral Hemorrhage: A Safe and Feasible Approach

Background and Purpose: Although outcome in intracerebral hemorrhage (ICH) patients is generally not improved by surgical intervention, the use of minimally invasive surgery (MIS) has shown promising results. However, vitamin K antagonist (VKA)-related ICH patients are underrepresented in surgical treatment trials. We therefore assessed the safety and efficacy of a bedside MIS approach including local application of urokinase in VKA-related ICH. Methods: Patients with a VKA-related ICH > 20 ml who received bedside hematoma evacuation treatment (n = 21) at the University Medical Center Freiburg were retrospectively included for analysis and compared to a historical control group (n = 35) selected from an institutional database (University Medical Center Erlangen) according to identical inclusion criteria. Propensity score matching was performed to obtain comparable cohorts. The evolution of hematoma and peri-hemorrhagic edema (PHE) volumes, midline shift, and the occurrence of adverse events were analyzed. Furthermore, we assessed the modified Rankin Scale and NIHSS scores recorded at discharge. Results: Propensity score matching resulted in 16 patients per group with well-balanced characteristics. Median ICH volume at admission was 45.7 (IQR: 24.2-56.7) ml in the control group and 48.4 (IQR: 28.7-59.6) ml in the treatment group (p = 0.327). ICH volume at day 7 was less pronounced in the treatment group [MIS: 23.2 ml (IQR: 15.8-32.3) vs. control: 43.2 ml (IQR: 27.5-52.4); p = 0.013], as was the increase in midline shift up to day 7 [MIS: -3.75 mM (IQR: -4.25 to -2) vs. control: 1 mM (IQR: 0-2); p < 0.001]. No group differences were observed in PHE volume on day 7 [MIS: 42.4 ml (IQR: 25.0-72.3) vs. control: 31.0 ml (IQR: 18.8-53.8); p = 0.274] or mRS at discharge [MIS: 5 (IQR: 4-5) and 5 (IQR: 4-5); p = 0.949]. No hematoma expansion was observed. The catheter had to be replaced in 1 patient (6%). Conclusions: Bedside catheter-based hematoma evacuation followed by local thrombolysis with urokinase appears to be feasible and safe in cases of large VKA-related ICH. Further studies that assess the functional outcome associated with this technique are warranted. Clinical Trial Registration: DRKS00007908 (German Clinical Trial Register; www.drks.de).

In-Vitro Study of Urokinase Thrombolysis Following Stereotactic Aspiration of Intracerebral Hematoma

Objective

A consensus regarding the ideal regimen for urokinase (UK) thrombolysis subsequent to stereotactic spontaneous intracerebral hemorrhage aspiration has yet to be established. The purpose of this study is to evaluate the efficacy of UK thrombolysis relative to when the regimen is changed.

Methods

Venous blood from 30 heathy volunteers was obtained for this in-vitro study. Various concentrations of UK solution were added to microcentrifuge tubes containing the clotted blood. The efficacy of UK thrombolysis was identified by checking the weight of lysed hematoma following various time intervals with different concentrations of UK solution. Group one, the “3×4” group involved four administrations every 3 hours over 12 hours, and group two, the “6×2” group involved two administrations every 6 hours over 12 hours.

Results

More hematoma was lysed in the 3×4 group than the 6×2 group across all concentration levels (however, the differences were only significant between groups at the 500 and 1000 IU concentration levels, p<0.05). There were no significant differences of lysed hematoma among the various UK solution concentrations within groups.

Conclusion

This study suggests that frequent administrations of UK thrombolysis may result in a greater degree of lysed hematoma in comparison to a higher concentration of UK.

Insufficient cerebral venous drainage predicts early edema in acute intracerebral hemorrhage

OBJECTIVES

To explore the relationship between insufficient ipsilateral cerebral venous drainage and the development of perihematomal edema (PHE) and functional outcome in patients with acute intracerebral hemorrhage (ICH).

METHODS

We retrospectively reviewed our prospectively collected database for patients with acute spontaneous supratentorial ICH and analyzed patients who underwent baseline CT perfusion (CTP) within 6 hours of onset and noncontrast CT at 24 hours. Absence of filling of 1 or more of the ipsilateral superficial middle cerebral vein, vein of Trolard, vein of Labbé, basal vein of Rosenthal, and internal cerebral vein, evaluated on venous maps generated from baseline CTP, was identified as absent ipsilateral venous filling (AIVF). Relative PHE (rPHE) was calculated as the ratio of PHE volume to hematoma volume on follow-up CT.

RESULTS

A total of 138 patients were included. Median absolute PHE volume on follow-up CT was 3.5 (1.0-9.3) mL and rPHE was 24.3% (9.0%-49.4%). One absent ipsilateral vein was observed in 38 (27.5%) patients, and 2 absent veins were observed in 5 (3.6%) patients. Multivariate analysis showed that AIVF was independently associated with large rPHE at 24 hours (odds ratio [OR] 4.032, 95% confidence interval [CI] 1.739-9.347, p < 0.001). Large PHE volume was independently associated with poor outcome (OR 1.109, 95% CI 1.009-1.218, p = 0.031).

CONCLUSION

AIVF was observed in about one-third of patients with acute ICH, which might be attributed to hypoperfusion after ICH and was strongly related to the development of PHE. Identification of cerebral venous filling status might be a promising imaging marker for PHE and a potential therapeutic target in ICH.

Stereotactic aspiration for hypertensive intracerebral haemorrhage in a Chinese population: a retrospective cohort study

Objective

We aimed to compare the therapeutic effects of stereotactic aspiration and best medical management in patients who developed supratentorial hypertensive intracerebral haemorrhage (HICH) with a volume of haemorrhage between 20 and 40 mL.

Methods

The clinical data of 220 patients with supratentorial HICH with a volume between 20 and 40 mL were retrospectively analysed. Among them, 142 received stereotactic aspiration surgery (stereotactic aspiration group) and 78 received best medical management (conservative group). All were followed up for 6 months. Multivariate logistic regression and Kaplan-Meier survival curves were used to compare the outcome between the two groups.

Results

The rebleeding rate was lower in the group that had stereotactic aspiration when compared with the group with medical treatment (6 [4.2%] vs 9 [11.5%], χ2=4.364, p=0.037). After 6 months, although the mortality rate did not differ significantly between the two groups (8 cases [5.6%] vs 10 cases [12.8%], χ2=3.461, p=0.063), the rate of a favourable outcome was higher in the group who received stereotactic aspiration (χ2=15.870, p=0.000). Logistic regression identified that medical treatment (OR=1.64, p=0.000) was an independent risk factor for an unfavourable outcome. The Kaplan-Meier curves indicated that the median favourable outcome time in the stereotactic aspiration group was 59.5 days compared with that in the medically treated group (87.0 days). The log-rank test indicated that the prognosis at 6 months was better for those treated with stereotactic haematoma aspiration (χ2=29.866, p=0.000). However, the 6-month survival rate was similar between the two groups (χ2=3.253, p=0.068).

Conclusions

Stereotactic haematoma aspiration significantly improved the quality of life, although did not effectively reduce the rate of mortality. When selected appropriately, patients with HICH may benefit from this type of surgical intervention.

Doppler sonography enhances rtPA-induced fibrinolysis in an in vitro clot model of spontaneous intracerebral hemorrhages

Background

Transcranial Doppler (TCD) was shown to enhance intravascular fibrinolysis by rtPA in ischemic stroke. Studies revealed that catheter-based administration of rtPA induces lysis of intracerebral hemorrhages (ICH). However, it is unknown whether TCD would be suitable to enhance rtPA-induced fibrinolysis in patients with ICH. The aim of this study was to assess the potential of TCD to enhance rtPA-induced fibrinolysis in an in vitro clot system.

Methods

Reproducible human blood clots of 25 ml were incubated in a water bath at 37°C during treatments. They were weighed before and after 6 different treatments: (I) control (incubation only), (II) rtPA only, (III) one Doppler probe, (IV) two Doppler probes placed vis-à-vis, (V) one probe and rtPA and (VI) two probes and rtPA. To quantify lysis of the blood clots and attenuation of the Doppler through a temporal squama acoustic peak rarefaction pressure (APRP) was measured in the field of the probes. Temperature was assessed to evaluate possible side effects.

Results

Clot weight was reduced in all groups. The control group had the highest relative end weight of 70.2%±7.2% compared to all other groups (p<0,0001). Most efficient lysis was achieved using (VI) 2 probes and rtPA 36.3%±4.4% compared to (II, III, IV) (p<0.0001; p = 0.0002; p = 0.048). APRP was above lysis threshold (535.5±7.2 kPa) using 2 probes even through the temporal squama (731.6±32.5 kPa) (p = 0.0043). There was a maximal temperature elevation of 0.17±0.07°C using both probes.

Conclusions

TCD significantly enhances rtPA-induced lysis of blood clots, and the effect is amplified by using multiple probes. Our results indicate that bitemporal TCD insonation of hematomas could be a new and safe approach to enhance fibrinolysis of ICH´s treated with intralesional catheter and rtPA.

The role of plasminogen activators in stroke treatment: fibrinolysis and beyond

Although recent technical advances in thrombectomy have revolutionised acute stroke treatment, prevalence of disability and death related to stroke remain high. Therefore, plasminogen activators-eukaryotic, bacterial, or engineered forms that can promote fibrinolysis by converting plasminogen into active plasmin and facilitate clot breakdown-are still commonly used in the acute treatment of ischaemic stroke. Hence, plasminogen activators have become a crucial area for clinical investigation for their ability to recanalise occluded arteries in ischaemic stroke and to accelerate haematoma clearance in haemorrhagic stroke. However, inconsistent results, insufficient evidence of efficacy, or reports of side-effects in trial settings might reduce the use of plasminogen activators in clinical practice. Additionally, the mechanism of action for plasminogen activators could extend beyond the vessel lumen and involve plasminogen-independent processes, which would suggest that plasminogen activators have also non-fibrinolytic roles. Understanding the complex mechanisms of action of plasminogen activators can guide future directions for therapeutic interventions in patients with stroke.

Optimized tPA: A non-neurotoxic fibrinolytic agent for the drainage of intracerebral hemorrhages

Intracerebral hemorrhage (ICH) is the most severe form of stroke. Catheter-delivered thrombolysis with recombinant tissue-type plasminogen activator (rtPA) for the drainage of ICH is currently under evaluation in a phase III clinical trial (MISTIE III). However, in a pig model of ICH, in situ fibrinolysis with rtPA was reported to increase peri-lesional edema by promoting N-methyl-D-aspartate (NMDA)-dependent excitotoxicity. In the present study, we engineered a non-neurotoxic tPA variant, OptPA, and investigated its safety and efficacy for in situ fibrinolysis in a rat model of ICH. Magnetic resonance imaging analyses of hematoma and edema volumes, behavioral tasks and histological analyses were performed to measure the effects of treatments. In vitro, OptPA was equally fibrinolytic as rtPA without promoting NMDA-dependent neurotoxicity. In vivo, in situ fibrinolysis using OptPA reduced hematoma volume, like rtPA, but it also reduced the evolution of peri-hematomal neuronal death and subsequent edema progression. Overall, this preclinical study demonstrates beneficial effects of OptPA compared to rtPA for the drainage of ICH.

Surgical Performance in Minimally Invasive Surgery Plus Recombinant Tissue Plasminogen Activator for Intracerebral Hemorrhage Evacuation Phase III Clinical Trial

BACKGROUND

Minimally invasive thrombolytic evacuation of intracerebral hematoma is being investigated in the ongoing phase III clinical trial of Minimally Invasive Surgery plus recombinant Tissue plasminogen activator for Intracerebral hemorrhage Evacuation (MISTIE III).

OBJECTIVE

To assess the accuracy of catheter placement and efficacy of hematoma evacuation in relation to surgical approach and surgeon experience.

METHODS

We performed a trial midpoint interim assessment of 123 cases that underwent the surgical procedure. Accuracy of catheter placement was prospectively assessed by the trial Surgical Center based on prearticulated criteria. Hematoma evacuation efficacy was evaluated based on absolute volume reduction, percentage hematoma evacuation, and reaching the target end-of-treatment volume of <15 mL. One of 3 surgical trajectories was used: anterior (A), posterior (B), and lobar (C). Surgeons were classified based on experience with the MISTIE procedure as prequalified, qualified with probation, and fully qualified.

RESULTS

The average hematoma volume was 49.7 mL (range 20.0-124), and the mean evacuation rate was 71% (range 18.4%-99.8%). First placed catheters were 58% in good position, 28% suboptimal (but suitable to dose), and 14% poor (requiring repositioning). Posterior trajectory (B) was associated with significantly higher rates of poor placement (35%, P = .01). There was no significant difference in catheter placement accuracy among surgeons of varying experience. Hematoma evacuation efficacy was not significantly different among the 3 surgical approaches or different surgeons' experience.

CONCLUSION

Ongoing surgical education and quality monitoring in MISTIE III have resulted in consistent rates of hematoma evacuation despite technical challenges with the surgical approaches and among surgeons of varying experience.

Modification of apparent intracerebral hematoma volume on T2∗-weighted images during normobaric oxygen therapy may contribute to false diagnosis

It was previously reported that normobaric oxygen therapy (NBO) significantly affected T2^∗-weighted imaging in a mouse model of intracerebral hemorrhage (ICH). However, it is unclear whether a similar phenomenon exists in large volume ICH as seen in human pathology. We investigated the effects of NBO on T2^∗-weighted images in a pig model of ICH. Our data show that NBO makes disappear a peripheral crown of the hematoma, which in turn decreases the apparent volume of ICH by 18%. We hypothesized that this result could be translated to ICH in human, and subsequently could lead to inaccurate diagnostic.

Combination of ultrasound and rtPA enhances fibrinolysis in an In Vitro clot system

BACKGROUND

Catheter-based lysis with recombinant tissue plasminogen activator (rtPA) is a well-established therapy for spontaneous intracerebral hemorrhage (ICH). The effectiveness of this therapy can be increased with ultrasound, but the optimal conditions are not yet clearly established. Using a novel in vitro system of blood clots previously developed by our group, we investigated various parameters of intralesional sonothrombolysis using an endosonography catheter in combination with rtPA.

METHODS

Standardized human blood clots were equipped with a drainage catheter and weighed before and after 4 treatments: control (drainage only), rtPA only, ultrasound only and the combination of rtPA+ultrasound. The effectiveness of ultrasound was further analysed in terms of optimal frequency, duration and distance to the probe. Temperature and acoustic peak rarefaction pressure (APRP) were assessed to analyse potential adverse effects and quantify lysis. Histo-morphological analysis of the treated clots was performed by H&E staining and confocal laser scanning microscopy using fluorescent fibrinogen.

RESULTS

The combined treatment rtPA+ultrasound achieved the highest lysis rates with a relative weight of 30.3%±5.5% (p≤0.0001) compared to all other groups. Similar results were observed when treating aged clots. Confocal fluorescent microscopy of the treated clots revealed a rarefied fibrin mesh without cavitations. No relevant temperature increase occurred (0.53±0.75°C). The optimal insonation treatment time was 1 hour. APRP measurements showed a lysis threshold of 515.5±113.4 kPa. Application of 10 MHz achieved optimal lysis and lysis radius, while simultaneously proving to be the best frequency for morphologic imaging of the clot and surrounding tissue.

CONCLUSIONS

These promising data provide the basis for an individualized minimal invasive ICH therapy by rtPA and sonothrombolysis independent of ICH age.

Urokinase vs Tissue-Type Plasminogen Activator for Thrombolytic Evacuation of Spontaneous Intracerebral Hemorrhage in Basal Ganglia

Spontaneous intracerebral hemorrhage (ICH) is a devastating form of stroke, which leads to a high rate of mortality and poor neurological outcomes worldwide. Thrombolytic evacuation with urokinase-type plasminogen activator (uPA) or tissue-type plasminogen activator (tPA) has been showed to be a hopeful treatment for ICH. However, to the best of our knowledge, no clinical trials were reported to compare the efficacy and safety of these two fibrinolytics administrated following minimally invasive stereotactic puncture (MISP) in patients with spontaneous basal ganglia ICH. Therefore, the authors intended here to evaluate the differential impact of uPA and tPA in a retrospective study. In the present study, a total of 86 patients with spontaneous ICH in basal ganglia using MISP received either uPA (uPA group, n = 45) or tPA (tPA group, n = 41), respectively. The clinical baseline characteristics prior to the operation were collected. In addition, therapeutic responses were assessed by the short-term outcomes within 30 days postoperation, as well as long-term outcomes at 1 year postoperation. Our findings showed that, in comparison with tPA, uPA was able to better promote hematoma evacuation and ameliorate perihematomal edema, but the differences were not statistically significant. Moreover, the long-term functional outcomes of both groups were similar, with no statistical difference. In conclusion, these results provide evidence supporting that uPA and tPA are similar in the efficacy and safety for thrombolytic evacuation in combination with MISP in patients with spontaneous basal ganglia ICH.

Comparison of endoscopic evacuation, stereotactic aspiration and craniotomy for the treatment of supratentorial hypertensive intracerebral haemorrhage: study protocol for a randomised controlled trial

BACKGROUND

Hypertensive intracerebral haemorrhage (HICH) is the most common form of haemorrhagic stroke with the highest morbidity and mortality of all stroke types. The choice of surgical or conservative treatment for patients with HICH remains controversial. In recent years, minimally invasive surgeries, such as endoscopic evacuation and stereotactic aspiration, have been attempted for haematoma removal and offer promise. However, research evidence on the benefits of endoscopic evacuation or stereotactic aspiration is still insufficient.

METHODS/DESIGN

A multicentre, randomised controlled trial will be conducted to compare the efficacy of endoscopic evacuation, stereotactic aspiration and craniotomy in the treatment of supratentorial HICH. About 1350 eligible patients from 10 neurosurgical centres will be randomly assigned to an endoscopic group, a stereotactic group and a craniotomy group at a 1:1:1 ratio. Randomisation is undertaken using a 24-h randomisation service accessed by telephone or the Internet. All patients will receive the corresponding surgery based on their grouping. They will be followed-up at 1, 3 and 6 months after surgery. The primary outcome is the modified Rankin Scale at 6-month follow-up. Secondary outcomes include: haematoma clearance rate; Glasgow Coma Scale 7 days after surgery; rebleeding rate; intracranial infection rate; hospitalisation time; mortality at 1 month and 3 months after surgery; the Barthel Index and the WHO quality of life at 3 months and 6 months after surgery.

DISCUSSION

The trial aims to investigate whether endoscopic evacuation and stereotactic aspiration could improve the outcome of supratentorial HICH compared with craniotomy. The trial will help to determine the best surgical method for the treatment of supratentorial HICH.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02811614 . Registered on 20 June 2016.

Optimization of Catheter Based rtPA Thrombolysis in a Novel In Vitro Clot Model for Intracerebral Hemorrhage

Hematoma lysis with recombinant tissue plasminogen activator (rtPA) has emerged as an alternative therapy for spontaneous intracerebral hemorrhage (ICH). Optimal dose and schedule are still unclear. The aim of this study was to create a reliable in vitro blood clot model for investigation of optimal drug dose and timing. An in vitro clot model was established, using 25 mL and 50 mL of human blood. Catheters were placed into the clots and three groups, using intraclot application of rtPA, placebo, and catheter alone, were analyzed. Dose-response relationship, repetition, and duration of rtPA treatment and its effectiveness in aged clots were investigated. A significant relative end weight difference was found in rtPA treated clots compared to catheter alone (p = 0.002) and placebo treated clots (p < 0.001). Dose-response analysis revealed 95% effective dose around 1 mg rtPA in 25 and 50 mL clots. Approximately 80% of relative clot lysis could be achieved after 15 min incubation. Lysis of aged clots was less effective. A new clot model for in vitro investigation was established. Our data suggest that current protocols for rtPA based ICH therapy may be optimized by using less rtPA at shorter incubation times.

Urokinase, a promising candidate for fibrinolytic therapy for intracerebral hemorrhage

OBJECTIVE Intracerebral hemorrhage (ICH) is associated with a high rate of mortality and severe disability, while fibrinolysis for ICH evacuation is a possible treatment. However, reported adverse effects can counteract the benefits of fibrinolysis and limit the use of tissue-type plasminogen activator (tPA). Identifying appropriate fibrinolytics is still needed. Therefore, the authors here compared the use of urokinase-type plasminogen activator (uPA), an alternate thrombolytic, with that of tPA in a preclinical study. METHODS Intracerebral hemorrhage was induced in adult male Sprague-Dawley rats by injecting autologous blood into the caudate, followed by intraclot fibrinolysis without drainage. Rats were randomized to receive uPA, tPA, or saline within the clot. Hematoma and perihematomal edema, brain water content, Evans blue fluorescence and neurological scores, matrix metalloproteinases (MMPs), MMP mRNA, blood-brain barrier (BBB) tight junction proteins, and nuclear factor-κB (NF-κB) activation were measured to evaluate the effects of these 2 drugs in ICH. RESULTS In comparison with tPA, uPA better ameliorated brain edema and promoted an improved outcome after ICH. In addition, uPA therapy more effectively upregulated BBB tight junction protein expression, which was partly attributed to the different effects of uPA and tPA on the regulation of MMPs and its related mRNA expression following ICH. CONCLUSIONS This study provided evidence supporting the use of uPA for fibrinolytic therapy after ICH. Large animal experiments and clinical trials are required to further explore the efficacy and safety of uPA in ICH fibrinolysis.

A Viewpoint on Treatment of Traumatic Bilateral Basal Ganglia Hemorrhage in a Child: Case Report

Traumatic basal ganglia hemorrhage (TBGH) is a rare presentation of head injuries. Bilateral lesions are extremely rare. The pathophysiologic mechanism of bilateral TBGH seems to be the same as diffuse axonal injury. However, limited information about childhood bilateral TBGH is available in the literature. We report the case of a child with bilateral TBGH treated with stereotactic aspiration of hemorrhage and periodic urokinase irrigation.

Treatment Strategies to Attenuate Perihematomal Edema in Patients With Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (SICH) continues to be a significant cause of neurologic morbidity and mortality throughout the world. Although recent advances in the treatment of SICH have significantly decreased mortality rates, functional recovery has not been dramatically improved by any intervention to date. There are 2 predominant mechanisms of brain injury from intracerebral hemorrhage: mechanical injury from the primary hematoma (including growth of that hematoma), and secondary injury from perihematomal inflammation. For instance, in the hours to weeks after SICH as the hematoma is being degraded, thrombin and iron are released and can result in neurotoxicity, free radical damage, dysregulated coagulation, and harmful inflammatory cascades; this can clinically and radiologically manifest as perihematomal edema (PHE). PHE can contribute to mass effect, cause acute neurologic deterioration in patients, and has even been associated with poor long-term functional outcomes. PHE therefore lends itself to being a potential therapeutic target. In this article, we will review 1) the pathogenesis and time course of the development of PHE, and 2) the clinical series and trials exploring various methods, with a focus on minimally invasive surgical techniques, to reduce PHE and minimize secondary brain injury. Promising areas of continued research also will be discussed.

No exacerbation of perihematomal edema with intraclot urokinase in patients with spontaneous intracerebral hemorrhage

BACKGROUND

Perihematomal edema (PHE) can worsen patient outcomes after spontaneous intracerebral hemorrhage (ICH). Minimally invasive surgery (MIS) in combination with thrombolytic removal of hematoma has been proven to be a promising treatment strategy. However, preclinical studies have suggested that intraclot thrombolysis may exacerbate PHE after ICH. Herein, we investigated the effects of MIS and urokinase on PHE.

METHODS

ICH patients were retrospectively identified from our institutional ICH database. Computerized volumetric analysis was applied to assess changes in both ICH and PHE volumes using computed tomographic (CT) scans of T1 (pre-MIS) and T2 (post-MIS) time points. Relative PHE (rPHE) was calculated as a ratio of PHE and T1 ICH volume.

RESULTS

Data from 60 MIS plus urokinase (MIS + U), 20 MIS aspiration only (MO), and 30 control patients were analyzed. The ICH volume, PHE volume and rPHE on T2 CT in both MIS + U and MO groups significantly decreased as compared with the control group (ICH volume, 13.7 ± 5.7 ml, 17.0 ± 10.5 ml vs. 30.5 ± 10.3 ml, P < 0.01; PHE volume, 36.5 ± 18.9 ml, 32.2 ± 17.5 ml vs. 45.4 ± 16.0 ml, P < 0.01; rPHE, 0.9 ± 0.4, 0.8 ± 0.4 vs.1.4 ± 0.5, P < 0.01). Between the MIS + U and MO groups, the ICH volume, PHE volume and rPHE at T2 trended towards similarity, but was not significant (P = 0.09, P = 0.40, P = 0.43). Furthermore, we found a significant correlation between the percent of ICH removal and PHE reduction (r = 0.59, P < 0.01). There was no correlation between the cumulative dose of urokinase and either T2 PHE volume (r = 0.19; P = 0.16) or T2 rPHE (r = -0.12; P = 0.37).

CONCLUSIONS

Hematoma evacuation using MIS leads to a significant reduction in PHE. Furthermore, the use of urokinase does not exacerbate PHE, making its hypothesized proedematous effects unlikely when the thrombolytic is administered directly into the clot.

Intraclot recombinant tissue-type plasminogen activator reduces perihematomal edema and mortality in patients with spontaneous intracerebral hemorrhage

The study aimed to investigate the impact of intraclot recombinant tissue-type plasminogen activator (rt-PA) on perihematomal edema (PHE) development in patients with intracerebral hemorrhage (ICH) treated with minimally invasive surgery (MIS) and the effects of intraclot rt-PA on the 30-day survival. We reviewed the medical records of ICH patients undergoing MIS between October 2011 and July 2013. A volumetric analysis was done to assess the change in PHE and ICH volumes at pre-MIS (T1), post-MIS (T2) and day 10-16 (T3) following diagnostic computed tomographic scans (T0). Forty-three patients aged 52.8±11.1 years with (n=30) or without rt-PA (n=13) were enrolled from our institutional ICH database. The median rt-PA dose was 1.5 (1) mg, with a maximum dose of 4.0 mg. The ratio of clot evacuation was significantly increased by intraclot rt-PA as compared with controls (77.9%±20.4% vs. 64%±15%; P=0.046). From T1 to T2, reduction in PHE volume was strongly associated with the percentage of clot evacuation (ρ=0.34; P=0.027). In addition, PHE volume was positively correlated with residual ICH volume at the same day (ρ ranging from 0.39-0.56, P<0.01). There was no correlation between the cumulative dose of rt-PA and early (T2) PHE volume (ρ=0.24; P=0.12) or delayed (T3) PHE volume (ρ=0.19; P=0.16). The 30-day mortality was zero in this cohort. In the selected cohort of ICH patients treated with MIS, intraclot rt-PA accelerated clot removal and had no effects on PHE formation. MIS aspiration and low dose of rt-PA seemed to be feasible to reduce the 30-day mortality in patients with severe ICH. A large, randomized study addressing dose titration and long-term outcome is needed.

Minimally invasive surgery for intracerebral haemorrhage

PURPOSE OF REVIEW

Spontaneous intracerebral haemorrhage (ICH) imposes a significant health and economic burden on society. Despite this, ICH remains the only stroke subtype without a definitive treatment. Without a clearly identified and effective treatment for spontaneous ICH, clinical practice varies greatly from aggressive surgery to supportive care alone. This review will discuss the current modalities of treatments for ICH including preliminary experience and investigative efforts to advance the care of these patients.

RECENT FINDINGS

Open surgery (craniotomy), prothrombotic agents and other therapeutic interventions have failed to significantly improve the outcome of these stroke victims. Recently, the Surgical Trial in Intracerebral Haemorrhage (STICH) II assessed the surgical management of patients with superficial intraparenchymal haematomas with negative results. MISTIE II and other trials of minimally invasive surgery (MIS) have shown promise for improving patient outcomes and a phase III trial started in late 2013.

SUMMARY

ICH lacks a definitive primary treatment as well as a therapy targeting surrounding perihematomal oedema and associated secondary damage. An ongoing phase III trial using MIS techniques shows promise for providing treatment for these patients.

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.

No exacerbation of perihematomal edema with intraventricular tissue plasminogen activator in patients with spontaneous intraventricular hemorrhage

INTRODUCTION

In severe spontaneous intraventricular hemorrhage (IVH), intraventricular (IVR) administration of tissue plasminogen activator (rtPA) clears blood from the ventricles more rapidly than with external ventricular drainage (EVD) alone. However, experimental studies suggest tPA may be neurotoxic in compromised brain tissue and may exacerbate perihematomal edema.

METHODS

We used computerized volumetrics to assess change in intracerebral hemorrhage (ICH), IVH, ventricular, and perihematomal edema (PHE) volumes at 2-4 (T1) and 5-9 (T2) days following diagnostic CT scans (T0) of 24 patients (12 tPA-treated; 12 controls) with IVH requiring EVD. Controls from a hospital registry were matched by IVH and ICH volume to tPA-treated patients who came from a multicenter trial involving 52 patients with IVH.

RESULTS

There were no significant differences between matched pairs in admission ICH and IVH volumes. IVR tPA resulted in more rapid clearance of IVH as determined by T2-T0 decrease in median IVH volume (tPA: -18.7 cc, iqr 14.9; control:-6.9 cc, iqr 6.4; P = 0.002). Median ratios of PHE to ICH volume were not significantly different in control versus tPA-treated patients at T1 and T2 [control:tPA = 0.55:0.56 (T1); P = 0.84 and 0.81:0.71 (T2); P = 1.00]. Total ventricular volume was significantly larger in the control group at T2 (mean: 57.57 ± 10.32 vs. tPA: 24.80 ± 2.67 cc; P = 0.01). Bacterial ventriculitis was more frequent in the control group (5 vs. 1 episodes; P = 0.06) as was shunt dependence (4 vs. 0 cases; P = 0.03).

CONCLUSIONS

For case matched large IVH with small ICH volume, IVR tPA enhances lysis of intraventricular blood clots and has no significant impact on PHE.

Image-guided implantation of pre-calibrated catheters in the ICU: a feasibility study

BACKGROUND

Image-guided implantation of intracranial catheters is a routine procedure. Although time for surgery is short, transport from the intensive care unit (ICU) to the operation room (OR) is time-consuming and endangers patients in vulnerable intracranial pressure phases. Unfortunately, technical aspects of image guidance have so far required surgery to be performed in the operation room. In this observational study we investigated the feasibility of image-guided catheter placement in the ICU using a pre-calibrated stylet for implantation of intracranial catheters for a variety of indications and compare the results of procedures performed in the OR.

METHODS

Twenty-three patients received implantation of 31 image-guided intracranial catheters or external ventricular drains using a pre-calibrated stylet in the ICU or in the OR. The times required for navigation planning, transport and surgery were assessed. Pre-operative trajectory planning, intra-operative screenshots of the navigation system and postoperative computed tomography (CT) scans were compared.

RESULTS

Eleven external ventricular drains and nine intracranial catheters for fibrinolytic therapy of intracerebral haemorrhage were implanted in the OR, whereas ten external ventricular drains and one catheter for fibrinolytic therapy were implanted in the ICU. All catheters implanted on the ICU, 81.8 % of external ventricular drains and 88.8 % of lysis catheters placed in the OR had an optimal position to function.

CONCLUSION

A pre-calibrated stylet in combination with the flexible headband equipped with reference arrays allows the application of image guidance in the ICU. It reduced time expended for patients and employees, and avoided the risks of ICU transport to the OR.

Transcranial MR-guided focused ultrasound sonothrombolysis in the treatment of intracerebral hemorrhage

Intracerebral hemorrhage remains a significant cause of morbidity and mortality. Current surgical therapies aim to use a minimally invasive approach to remove as much of the clot as possible without causing undue disruption to surrounding neural structures. Transcranial MR-guided focused ultrasound (MRgFUS) surgery is an emerging technology that permits a highly concentrated focal point of ultrasound energy to be deposited to a target deep within the brain without an incision or craniotomy. With appropriate ultrasound parameters it has been shown that MRgFUS can effectively liquefy large-volume blood clots through the human calvaria. In this review the authors discuss the rationale for using MRgFUS to noninvasively liquefy intracerebral hemorrhage (ICH), thereby permitting minimally invasive aspiration of the liquefied clot via a small drainage tube. The mechanism of action of MRgFUS sonothrombolysis; current investigational work with in vitro, in vivo, and cadaveric models of ICH; and the potential clinical application of this disruptive technology for the treatment of ICH are discussed.

Effects of high-frequency oscillatory ventilation on systemic and cerebral hemodynamics and tissue oxygenation: an experimental study in pigs

BACKGROUND

In this study, we compare the effects of high frequency oscillatory ventilation (HFOV) with those of lung-protective volume-controlled ventilation (VCV) on cerebral perfusion, tissue oxygenation, and cardiac function with and without acute intracranial hypertension (AICH).

METHODS

Eight pigs with healthy lungs were studied during VCV with low tidal volume (V(T): 6 ml kg(-1)) at four PEEP levels (5, 10, 15, 20 cm H(2)O) followed by HFOV at corresponding transpulmonary pressures, first with normal ICP and then with AICH. Systemic and pulmonary hemodynamics, cardiac function, cerebral perfusion pressure (CPP), cerebral blood flow (CBF), cerebral tissue oxygenation, and blood gases were measured after 10 min at each level. Transpulmonary pressures (TPP) were calculated at each PEEP level. The measurements were repeated with HFOV using continuous distending pressures (CDP) set at TPP plus 5 cm H(2)O for the corresponding PEEP level. Both measurement series were repeated after intracranial pressure (ICP) had been raised to 30-40 cm H(2)O with an intracranial balloon catheter.

RESULTS

Cardiac output, stroke volume, MAP, CPP, and CBF were significantly higher during HFOV at normal ICP. Systemic and cerebral hemodynamics was significantly altered by AICH, but there were no differences attributable to the ventilatory mode.

CONCLUSION

HFOV is associated with less hemodynamic compromise than VCV, even when using small tidal volumes and low mean airway pressures. It does not impair cerebral perfusion or tissue oxygenation in animals with AICH, and could, therefore, be a useful ventilatory strategy to prevent lung failure in patients with traumatic brain injury.

Minimally invasive treatment of intracerebral hemorrhage with magnetic resonance-guided focused ultrasound

OBJECT

Intracerebral hemorrhage (ICH) is a major cause of death and disability throughout the world. Surgical techniques are limited by their invasive nature and the associated disability caused during clot removal. Preliminary data have shown promise for the feasibility of transcranial MR-guided focused ultrasound (MRgFUS) sonothrombolysis in liquefying the clotted blood in ICH and thereby facilitating minimally invasive evacuation of the clot via a twist-drill craniostomy and aspiration tube.

METHODS AND RESULTS

In an in vitro model, the following optimum transcranial sonothrombolysis parameters were determined: transducer center frequency 230 kHz, power 3950 W, pulse repetition rate 1 kHz, duty cycle 10%, and sonication duration 30 seconds. Safety studies were performed in swine (n = 20). In a swine model of ICH, MRgFUS sonothrombolysis of 4 ml ICH was performed. Magnetic resonance imaging and histological examination demonstrated complete lysis of the ICH without additional brain injury, blood-brain barrier breakdown, or thermal necrosis due to sonothrombolysis. A novel cadaveric model of ICH was developed with 40-ml clots implanted into fresh cadaveric brains (n = 10). Intracerebral hemorrhages were successfully liquefied (> 95%) with transcranial MRgFUS in a highly accurate fashion, permitting minimally invasive aspiration of the lysate under MRI guidance.

CONCLUSIONS

The feasibility of transcranial MRgFUS sonothrombolysis was demonstrated in in vitro and cadaveric models of ICH. Initial in vivo safety data in a swine model of ICH suggest the process to be safe. Minimally invasive treatment of ICH with MRgFUS warrants evaluation in the setting of a clinical trial.

Minimally invasive treatment for intracerebral hemorrhage

Spontaneous intracerebral hemorrhage is a serious public health problem and is fatal in 30%-50% of all occurrences. The role of open surgical management of supratentorial intracerebral hemorrhage is still unresolved. A recent consensus conference sponsored by the National Institutes of Health suggests that minimally invasive techniques to evacuate clots appear to be a promising area and warrant further investigation. In this paper the authors review past, current, and potential future methods of treating intraparenchymal hemorrhages with minimally invasive techniques and review new data regarding the role of stereotactically placed catheters and thrombolytics.

Management of non-traumatic intraventricular hemorrhage

Intraventricular hemorrhage (IVH) is defined as the eruption of blood in the cerebral ventricular system and is mostly secondary to spontaneous intracerebral hemorrhage and aneurysmal and arteriovenous malformation rupture. IVH is a proven risk factor of increased mortality and poor functional outcome. Its seriousness is correlated not only with the amount of blood but also with the involvement of the third and fourth ventricles. There are four mechanisms that explain the pathophysiology of this event: acute obstructive hydrocephalus, the mass effect exerted by the blood clot, the toxicity of blood-breaking products on the adjacent brain parenchyma, and, lastly, the development of a chronic hydrocephalus. It is thus obvious that the clearance of blood from the ventricles should be a therapeutic goal. In cases of acute hydrocephalus, external ventricular drainage is a mandatory step, but proven often insufficient. The concomitant use of intraventricular fibrinolytics such as recombinant tissue plasminogen activator or urokinase seems to be beneficial at least in the context of spontaneous intracerebral hemorrhage, in which their use is now accepted but not yet validated by a randomized trial. Given the potential neurotoxicity of these agents, further research is needed in order to identify the best treatment for intraventricular fibrinolysis (IVF). The endoscopic retrieval of intraventricular blood was also described recently and seems to be as efficient as IVF, but its use is limited to specialized centers. IVH represents a therapeutic challenge for neurosurgeons, neurologists, and intensivists. Thus, a better understanding of this dramatic event will help in better tailoring the treatment strategies.

Tissue plasminogen activator induced delayed edema in experimental porcine intracranial hemorrhage: reduction with plasminogen activator inhibitor-1 administration

Hematoma puncture and subsequent clot lysis with recombinant tissue plasminogen activator (rtPA) emerged as an alternative therapy for spontaneous intracerebral hemorrhage (ICH) and is associated with delayed edema possibly counteracting the beneficial effects of hematoma volume reduction. We hypothesized that immediate reversal of rtPA activity after clot lysis and hematoma drainage diminishes edema formation. To test this hypothesis, we administered plasminogen activator inhibitor (PAI)-1 after rtPA lysis of experimentally induced ICH. A right frontal ICH was placed through a twist drill burr hole and autologous blood injection. Following creation of the frontal ICH, pigs received no further treatment (n = 5), lysis with rtPA (n = 7), or lysis with rtPA followed by administration of PAI-1 (n = 6). Hematoma and edema volumes were assessed with magnetic resonance imaging on days 0, 4, and 10. The rtPA significantly reduced hematoma volume and contributed to edema on day 10 after experimentally induced ICH. Administration of PAI-1 attenuated the rtPA-induced edema volume on day 10, but the hematoma volume reduction was less pronounced. In conclusion, PAI-1 attenuated delayed cerebral edema after rtPA lysis of experimental ICH but also reduced the lytic activity of rtPA. The combination of rtPA clot lysis with PAI-1 might have the potential to further improve the effect of the lytic therapy of ICH, but additional studies to define the optimum time point for PAI-1 administration are required.

Intracerebral hemorrhage: clinical overview and pathophysiologic concepts

Intracerebral hemorrhage is by far the most destructive form of stroke. Apart from the management in a specialized stroke or neurological intensive care unit (NICU), no specific therapies have been shown to consistently improve outcomes after ICH. Current guidelines endorse early aggressive optimization of physiologic derangements with ventilatory support when indicated, blood pressure control, reversal of any preexisting coagulopathy, intracranial pressure monitoring for certain cases, osmotherapy, temperature modulation, seizure prophylaxis, treatment of hyerglycemia, and nutritional support in the stroke unit or NICU. Ventriculostomy is the cornerstone of therapy for control of intracranial pressure patients with intraventricular hemorrhage. Surgical hematoma evacuation does not improve outcome for more patients, but is a reasonable option for patients with early worsening due to mass effect due to large cerebellar or lobar hemorrhages. Promising experimental treatments currently include ultra-early hemostatic therapy, intraventricular clot lysis with thrombolytics, pioglitazone, temperature modulation, and deferoxamine to reduce iron-mediated perihematomal inflammation and tissue injury.