Large Cerebral Artery Occlusion Research Articles

In-hospital mortality in patients with ischemic stroke and a large cerebral artery occlusion, who underwent mechanical thrombectomy

Occlusion of a large cerebral artery in ischemic stroke (IS) is associated with a high mortality rate. Despite the results of studies that have demonstrated the beneficial effect of endovascular therapy on functional outcome in IS, little research has been conducted on its impact on hospital mortality in IS, its timing and structure.Objective: to investigate hospital mortality in patients with IS and large cerebral artery occlusion, who underwent mechanical thrombectomy (MTE).Material and methods. The retrospective study included data from 233 patients with IS and confirmed occlusion of a large cerebral artery (internal carotid artery, M1 and M2 segments of the middle cerebral artery, basilar artery) treated at the regional vascular center V.V. Veresaev Hospital, Moscow, 2018 and 2022. A comparison of hospital mortality in the group of patients who underwent MTE and the group of patients who received basic therapy was performed.Results. MTE was performed in 107 patients (46%); 126 patients (54%) received only basic therapy. The mortality rate of all patients included in the study was 44.2%. Among all deaths, the proportion of patients with MTE was only 7.2%, while the proportion of patients on basic therapy was 36.9% (p<0.001). Mortality in the MTE group was four times lower than in the basic therapy group – 15.8% compared to 68.2% (p<0.001). We observed that certain manifestations were significantly more frequent in the basic therapy group: cerebral edema (42% vs. 18.6%), hemorrhagic transformation (19.9% vs. 12.9%), venous thromboembolism (6.3% vs. 3.7%) and infectious complications (42.8% vs. 14.3%). The mortality of patients in the basic therapy group was higher on the first day, on days 2–3 and also on days 4–7, while no differences in mortality were observed after the first week of the disease.Conclusion. Admission of a patient with IS within the “therapeutic window” creates the conditions for a significant reduction in hospital mortality and the incidence of stroke complications.

Mechanical Thrombectomy by Stent Retrievers for Treating Acute Ischemic Stroke due to Large Vessel Occlusion

Background Recently multiple studies have evaluated the role of mechanical thrombectomy in treatment of acute ischemic stroke & demonstrated that it has a favorable impact on the functional outcome in patients with acute ischemic stroke related to proximal arterial occlusion. In addition to that, multiple systematic reviews and meta-analyses analyzed the results of these recent Randomized Control Trials and concluded that endovascular treatment is more likely to result in a better functional outcome for patients compared to IV thrombolysis alone for acute ischemic stroke due to large vessel occlusion, with no differences in mortality and symptomatic intracerebral hemorrhage at 90 days follow-up. Mechanical approaches have shown great potential of replacing locally applied thrombolytic agents as first-line therapy. Objectives The aim of work is to evaluate the safety and efficacy of endovascular treatment (EVT) of acute large vessel occlusion within the first 6 hours of symptoms onset, including bridging therapy [intravenous thrombolysis (IVT) with subsequent EVT]. We also compare our results to other main trials in recent years. Methods A one arm clinical trial was conducted on 25 patients with acute ischemic stroke at Ain Shams University hospitals as well as private centers, from the first of April 2020 to the end of September 2020. All participants subjected to full history taking, radiological assessment and assessment of the stroke severity. Results The median age of the studied patients was 64 years (Interquartile range 58-72.5) and about half (56%) of them were males. On pre-post intervention comparison, there was a highly significant statistical difference regarding NIHSS score, infarct volume, mRS score at 90 days (P < 0.001) and ASPECTS (P < 0.01) of the studied patients. 12% of patients had mortality at 30 days after mechanical thrombectomy with good functional outcome (mRS 0-2) rate of 60%. Conclusion Mechanical thrombectomy is effective and safe in treatment of acute ischemic stroke in patients with large cerebral artery occlusion with the first 6 hours of symptoms onset.

Endovascular treatments for ischemic stroke

Highlights. Mechanical thrombectomy is the “gold standard” treatment of patients with large-vessel occlusions. Five randomized trials conducted in 2015 made a significant contribution to the development and introduction of mechanical thrombectomy into clinical practice. The DAWN and DEFUSE-3 trials have provided new insights into the pathophysiology of ischemic stroke and ensured the advancement in the therapeutic field.Abstract. Stroke is one of the leading causes of death and disability worldwide. The general strategy for the treatment of ischemic stroke is aimed at restoring blood flow to the ischemic regions of the brain. Intravenous thrombolysis has been the treatment for acute ischemic stroke since 1996. However, since 2015, as a result of 5 randomized trials, endovascular mechanical thrombectomy has become the gold standard for the treatment of patients with large cerebral artery occlusion. The DAWN and DEFUSE 3 trials have provided new insights into the pathophysiology of ischemic stroke, shifting the paradigm from “time = brain” to “collaterals = brain”. In this article, the authors will consider development of endovascular devices, modern mechanical thrombectomy techniques, and directions for further research of endovascular treatment for ischemic stroke.

Use of a Smartphone Application to Speed Up Interhospital Transfer of Acute Ischemic Stroke Patients for Thrombectomy.

Background: In most countries, large cerebral artery occlusion is identified as the leading cause of disability. In 2015, five large-scale clinical trials confirmed the benefit of intra-arterial thrombectomy. However, thrombectomy is a highly technical and facility-dependent procedure. Primary stroke centers need to transfer patients to comprehensive stroke centers to perform thrombectomy. The time-lapse during interhospital transfer would decrease the chance of the patient's proper recovery. Communication barriers also contribute to this delay.Aims: We used a smartphone application to overcome communication barriers between hospitals. We aimed to shorten the door-to-puncture time of interhospital transfer patients.Methods: We began using a smartphone application, “LINE,” to facilitate interhospital communication on May 01, 2018. We carried out retrospective data analyses for all the transfer patients (n = 351), with the primary outcome being the door-to-puncture time in our comprehensive stroke center (China Medical University Hospital). We compared the three periods: May 01 to Dec 31, 2017 (before the use of the smartphone application); May 01 to Dec 31, 2018 (the 1st year of using the smartphone application); and May 01 to Dec 31, 2019 (the 2nd year of using the smartphone application). We also compared the transfer data with non-transfer thrombectomies in the same period.Results: We compared 2017, 2018, and 2019 data. The total number of transfer patients increased over the years: 63, 113, 175, respectively. The mean door-to-puncture time decreased significantly, going from 109, through 102, to 92 min. Meanwhile, the mean door-to-puncture time in non-transfer patients were 140.3, 122.1, and 129.3 min. The main reason of time saving was the change of the way of communication, from point-to-point interhospital communication to hub-to-spoke interhospital communication.Conclusions: We used this smartphone application to enhance interhospital communication, changed from the point-to-point to hub-to-spoke method. It made us overcome the communication barrier and build up interhospital connection, thus shortening the door-to-puncture time. Our experience demonstrated the importance of close communication and teamwork in hyperacute stroke care, especially in interhospital transfer for thrombectomy.

Results of Mechanical Thrombectomy 6 Hours after Stroke Onset: Analysis of Multiple Stroke Centers in Fukushima Prefecture.

The purpose of this study was to examine the efficacy and safety of mechanical thrombectomy in patients with acute occlusion of a large cerebral artery in the anterior circulation beyond 6 hours of the time last known to be well using the real-world clinical data collected from non-urban areas of Japan. We analyzed a retrospective multicenter database collected at 10 thrombectomy capable primary stroke centers in Fukushima Prefecture. In all, 188 patients were presenting a large cerebral artery occlusion in the anterior circulation, that is, internal carotid and middle cerebral artery (M1 and M2 segment). In all, 158 patients received mechanical thrombectomy within 6 hours from symptom onset (early time window), and 30 patients exceeded 6 hours (late time window). We compared the patient background, outcomes, and safety variables between the two groups. The modified Rankin Scale (mRS) score of 0-2 at 90 days after treatment and the incidence of symptomatic intracranial hemorrhage were compared between groups to evaluate treatment efficacy and safety. There was no significant difference in the proportion of mRS score 0-2 at 90 days after treatment (51.3 vs. 46.7%: P = 0.644). However, symptomatic intracranial hemorrhage was more frequent in the late time window group (7.0 vs. 16.7%: P = 0.081). Symptomatic intracranial hemorrhage was a significant factor of a poor functional outcome in the late time window group (P = 0.022). This study reflects the real-world results of mechanical thrombectomy in the non-urban areas of Japan. The treatment efficacy in the late time window patients was equivalent to that in the early time window patients. On the other hand, the incidence of symptomatic intracranial hemorrhage showed a trend to high in patients beyond 6 hours, which was a significant factor related to a poor functional outcome.

Persistance of Inflammatory Phenotype of Neutrophils in Sickle Cell Disease Children Despite Chronic Exchange Transfusion Program: A Cause of the Progression of Cerebral Vasculopathy?

Sickle cell disease (SCD) is a severe hemoglobinopathy due to the production of abnormal hemoglobin S (HbS). Although red blood cell (RBC) dysfunction is the major contributor to disease, several studies highlighted the important role of polymorphonuclear neutrophils (PMNs), both during acute and chronic complications. One of the most severe complication of SCD is ischemic stroke due to large cerebral artery occlusion. In 1998, the Stroke Prevention (STOP) trial demonstrated that monthly blood transfusions could reduce the risk of stroke by 90% in SCD children with cerebral vasculopathy (CV). However, there is a wide heterogeneity in the course of CV in patients receiving chronic transfusions, since only about half of them improved their CV under transfusion program, while 25% are only stabilized and 29% continue to get worse despite a percentage of HbS permanently below 30%. The aim of our study is to investigate the impact of transfusion programs on neutrophils activation and ageing, in order to identify if inflammation could contribute to the persistence of SCD complications despite red cell transfusion. We performed a prospective study including 58 homozygous SCD children and 10 healthy donors. Of these, 12 had no specific treatment, 11 were on Hydroxyurea (HU) treatment, 21 were on an exchange transfusion program, and 14 were on both an exchange transfusion program and HU treatment for an average of 4.9 years due to persistent CV. Monthly exchange transfusion are carried out either by erythrapheresis or by manual exchanges, consisting of the continuous bleeding of whole blood compensated by simultaneous transfusion of packed red blood cells. Neutrophils were isolated from fresh blood samples before exchange transfusion session and labelled with 8 markers specific of adhesion, activation and ageing. We quantified by flow cytometry the expression of 3 integrins (CD18, CD11a, CD11b), 3 ageing markers (CD182, CD184, CD62L) and 2 adhesion molecules (CD162 and CD66a). We also measured the plasmatic level of elastase, which reflects the NETose activity of PMNs As previously reported, we observed a high leukocytosis and an activated profile of PMNs in the 12 non-transfused SCD patients compared to healthy controls (Figure 1), characterized by an overexpression of the integrin CD18/CD11b (p=0,03) and CD18/CD11a (p=0,02), a higher level of circulating aged PMNs CD184 high/CD62Llow (p=0,04), a higher expression of CD162 (p=0,01) and CD66a (0,01) as well as a higher plasmatic level of elastase (p=0.01). Interestingly, in the PMNs of the 21 patients receiving monthly exchange transfusion, we found an identical expression pattern of integrins, selectins, ageing markers and elastase level compared to those of the PMNs from non-transfused patients. Furthermore, we also observed a persistence of high neutrophilic leukocytosis. This activation pattern was the same for patients on manual exchange or erythrapheresis, even with a tendency towards a more inflammatory profile in patients on erythrapheresis (Figure 1). In the PMNs from the 11 patients receiving HU compared to untreated SCD patients, we found an expected decrease in high leukocytosis and membrane integrin expression CD18/CD11b and CD18/CD11a. The addition of HU therapy in 14 patients in exchange transfusion program allows to alleviate neutrophilic leukocytosis and membrane integrin expression. Our study shows for the first time that replacing sickle RBCs with healthy RBCs is not sufficient to reverse the pathological phenotype of PMNs in SCD. A persistence of the PMNs activation pattern is observed both despite erythrapheresis, where plasma and white blood cells go back to the patient, and in manual exchanges, where the patient is bled from a large volume of whole blood. Given the major role of inflammation in endothelial damage and vasculopathy in SCD, our data could explain the incomplete efficacy of transfusion exchange programs to treat CV. This raises the question to systematically combine anti-inflammatory and anti-white blood cell adhesion treatments such as Hydroxyurea or P-Selectin inhibitors for these patients. Disclosures No relevant conflicts of interest to declare.

Endovascular treatment results in patients with large cerebral artery occlusions in a metropolis. Moscow Stroke Registry data over 2019

Objective: to assess results from the Stroke Network created on the basis of the Infarction Network in the metropolis Moscow for endovascular treatment in patients with occlusion of the large cerebral artery (the internal carotid artery, the M1 and M2 segments of the middle cerebral artery, and the main artery).Patients and methods. A total of 742 thromboextractions were performed in patients with ischemic stroke in Moscow Stroke Network hospitals in 2019. The final analysis included 729 patients aged 25 to 97 years (mean age, 71 years); of them there were 370 (50.8%) men and 359 (49.2%) women. The selection criteria for endovascular treatment for ischemic stroke were consistent with those set out in the 2015 American Heart Association/American Stroke Association (AHA/ASA) guidelines, which included a pre-stroke modified Rankin Scale (MRS) score of 0–1; ≥18 years of age; a National Institutes of Health Stroke Scale (NIHSS) score of ≥6; and an Alberta Stroke Programme Early CT score (ASPECTS) ≥6. The angiographic results were assessed using the Thrombolysis in Cerebral Infarction (TICI) scale. The clinical outcomes were measured with the NIHSS and the MRS.Results and discussion. Successful recanalization (TICI 2b/3) was achieved in 547 (75%) patients. The predominant technique for thromboextraction was thromboaspiration that was used in 376 (51.6%) patients. Combined procedures (the co-use of an aspiration catheter and a stent retriever) were the second most commonly used – in 231 (31.7%) patients. By the end of the 20th day, good functional recovery (MSR 0–2 scores) was observed in 213 (29.2%) patients. The 20-day mortality rate was 31.8%.Conclusion. The successfully functioning Infarction Network in Moscow was used to create the Stroke Network for treatment in patients with ischemic stroke and large cerebral artery occlusion, the clinical results of which are comparable to large European registry studies.

Immunohistological Analysis of Neutrophils and Neutrophil Extracellular Traps in Human Thrombemboli Causing Acute Ischemic Stroke.

Ischemic stroke caused by thromboembolic occlusion of large cerebral arteries, such as the internal carotid (ICA) and/or the middle cerebral artery (MCA), is treated by mechanical thrombectomy (MT). MT allows salvage of the vessel-occluding thrombemboli, which most frequently originate from the left atrium or the left ventricle of the heart or from sites of plaque rupture within large arteries above the heart. Clot composition may influence the efficacy of (intravenous) thrombolysis and MT, respectively. We analyzed 37 human thrombemboli obtained from acute ischemic stroke patients during MT with special emphasis on histological staining of neutrophils and neutrophil extracellular traps (NETs). We found neutrophils as the main cellular component of cerebral thrombemboli but encountered considerable morphological heterogeneity. Neutrophils accumulated in the border region of fibrin-rich structures indicating possible interaction of neutrophils with distinct structural thrombembolus components. Web-like NETs were found in 35 of 37 thrombemboli in varying amounts. NETs were almost exclusively found within fibrin-rich areas. Importantly, stroke etiology, age and present oral anticoagulation was associated with morphological patterns and the amount of neutrophils. Correlation of histological data and imaging data revealed that relative Hounsfield units of cerebral thrombemboli positively correlated with the amount of red blood cells. In summary, our results demonstrate that neutrophils and NETs are substantial constituents of cerebral thrombemboli and contribute to their structural complexity.

Effect of Recanalization on Cerebral Edema, Long-Term Outcome, and Quality of Life in Patients with Large Hemispheric Infarctions

ObjectivesSpace-occupying cerebral edema is the main cause of mortality and poor functional outcome in patients with large cerebral artery occlusion (LVO). We aimed to determine whether recanalization of LVO would augment cerebral edema volume and the impact on functional outcome and quality of life (QoL). Materials and MethodsProspectively, 43 patients with large middle cerebral artery territory infarction or NIHSS ≥ 12 on admission were enrolled. The degree of recanalization (partial and complete versus no recanalization) was assessed by computed tomography (CT)-angiography or Duplex ultrasound more than 24 h after symptom onset. Cerebral edema volume was measured on follow up CTs by computer-based planimetry. Mortality, functional outcome (by modified Ranking Scale (mRS) and Barthel Index (BI)) were assessed at discharge and 12 months, and QoL (by SF-36 and EQ-5D-3L) at 12 months. ResultsMean cerebral edema volume was 333±141 ml without recanalization (n=13, group 1) and 276±140 ml with partial or complete recanalization (n=30, group 2, p= 0.23). There were no significant differences in mortality at discharge (38% versus 23%), at 12 months (58% versus 48%), in functional outcome at discharge (mRS 0–3: 0% both; mRS 4–5: 62% versus 77%) and at 12 months (mRS 0–3: 0% versus 11%; mRS 4–5: 42% versus 41%). The BI improved significantly from discharge to 12 months only in group 2 (p=0.001). Mean physical component score in SF-36 was 25.6±6.4, psychological component score was 41.9±14.1. In the EQ-5D-3L, most patients reported problems with activities of daily living, reduced mobility, and selfcare. ConclusionsRecanalization of a large cerebral artery occlusion in the anterior circulation territories is not associated with amplification of post-ischemic cerebral edema but may be correlated with better long-term functional outcome. QoL was low and mainly dependent on physical disability. The association between recanalization, collateral status and development of cerebral edema after LVO and the effect on functional outcome and quality of life should be explored in a larger patient population.

Acute progressive stroke with middle cerebral artery occlusion caused by idiopathic hypereosinophilic syndrome: a case report

BackgroundIdiopathic hypereosinophilic syndrome (IHES) is associated with various organ system dysfunctions. Neurologic abnormalities have been previously noted in this syndrome. Cerebral infarction secondary to occlusion of large cerebral artery is rarely reported. Here we described a patient with IHES presented progressive multiple cerebral infarctions caused by bilateral middle cerebral artery occlusion.Case presentationA 55-year-old Chinese woman presented to our hospital with acute onset of right limbs weakness and slurred speech. Laboratory tests showed a significant eosinophilia of 5.29 × 109/L (normal, < 0.5), 49.9% of leukocytes. Brain magnetic resonance imaging (MRI) revealed multiple acute cerebral ischemic lesions. Magnetic resonance angiography (MRA) demonstrated stenosis in horizontal segment of right middle cerebral artery. A pretibial skin biopsy revealed eosinophilic infiltration around the capillaries in deep dermis and adipose tissue. The patient was given oral dual anti platelet agents and intravenous methylprednisolone. However, one week later, the patient presented significant neurological deterioration with right-sided hemiparesis and totally motor aphasia. Brain MRI and computed tomography perfusion (CTP) demonstrated new acute cerebral ischemia in left hemisphere. Digital subtraction angiography (DSA) revealed left middle cerebral artery completely occluded. The patient received a high-dose of intravenous methylprednisolone 500 mg per day and the eosinophil count quickly fell to normal within 2 days. She was transferred to a rehabilitation center and her neurological symptoms improved with modified Ranking Scale from 4 to 2.ConclusionsIHES is one of the rare causes of acute ischemic stroke with large cerebral artery occlusion. An early high-dose of corticosteroids therapy should be considered in cases of IHES patients. Our case study is benefit to clinical diagnosis and treatment of cerebral infarction with IHES.

Mechanical thrombectomy in isolated large vessel posterior cerebral artery occlusions.

Mechanical thrombectomy (MT) in posterior circulation large vessel occlusion (LVO), including posterior cerebral artery (PCA), has not been validated since all five major MT trials excluded such patients. To evaluate the feasibility and preliminary safety and efficacy of MT in isolated PCA occlusion stroke patients with new-generation MT devices. Endovascularly treated acute ischemic stroke (AIS) patients were identified from a prospectively collected database and their baseline characteristics were noted. Clinical outcomes were angiographic recanalization, a favorable clinical outcome at 3months on modified Rankin Scale (mRS) and visual field (VF) deficit improvement on confrontation test, rate of intracranial hemorrhage (ICH), and mortality at 3months. A total of 355 AIS patients underwent MT from January 2018 to December 2019. Isolated PCA MT was performed in 15 consecutive patients. The mean age was 64 ± 17years, and 9(60%) were women. Median presentation NIHSS was 9 (interquartile range 5-15). MT devices used were stent retrievers in 6 patients and combined aspiration and stent retriever in 9 patients. Complete revascularization (TICI 2c or 3) was achieved in 12/15 patients. 3-month VF normalization was seen in 7/12 of the patients. Post-procedure symptomatic ICH occurred in 1/15 of patients. mRS score of 0-2 was achieved in 9/15 of patients but one patient was dead at 3months post procedure. MT is feasible and can achieve successful reperfusion in isolated PCA occlusions and resulted in favorable motor and visual outcomes in this small series of ischemic stroke patients.

Combined transcatheter thrombectomy system for treatment of acute ischaemic stroke

Background. Since 1996, thrombolytic therapy with tissue plasminogen activator has traditionally been the first-line treatment for patients with ischaemic stroke. However, the results of recent randomised trials have shown the advantage of mechanical thrombectomy over thrombolytic therapy for successful revascularisation of brain arteries and improvement of clinical outcomes. Owing to the development of endovascular surgery, mechanical thrombectomy has now become an effective and safe method for treating ischaemic stroke resulting from the occlusion of large cerebral arteries.Aim. The main aim of this study was to develop a prototype for a combined transcatheter system to be used for mechanical thrombectomy.Methods. During the implementation of the project, we first analysed the data on the problems to justify the choice of standard sizes of a stent retriever and an aspiration catheter and to determine the basic set of physical–mechanical, functional and biomedical characteristics of the system. A prototype of a combined transcatheter system for mechanical thrombectomy, which comprises an aspiration catheter and a stent retriever, was manufactured. Moreover, preclinical tests were conducted to study the physical properties of the developed prototype and assess its effectiveness. Results. Data from preclinical tests showed a level of radial stiffness of the prototype that was comparable to that of a similar device on the market, satisfactory visualisation under angiography and high efficiency while performing mechanical thrombectomy in vitro and in vivo tests.Conclusions. Studies on the prototype of the combined transcatheter system for thrombectomy have shown positive results in preclinical trials.Received 5 December 2019. Revised 18 December 2019. Accepted 20 December 2019.Funding: The study did not have sponsorship.Conflict of interest: Authors declare no conflict of interest.

Supratentorial Cerebral Arterial Territories for Computed Tomograms: A Mapping Study in 1160 Large Artery Infarcts

We recently generated a high-resolution supratentorial vascular topographic atlas using diffusion-weighed MRI in a population of large artery infarcts. These MRI-based topographic maps are not easily applicable to CT scans, because the standard-reference-lines for axial image orientation (i.e., anterior-posterior commissure line versus orbito-meatal line, respectively) are ‘not parallel’ to each other. Moreover, current, widely-used CT-based vascular topographic diagrams omit demarcation of the inter-territorial border-zones. Thus, we aimed to generate a CT-specific high-resolution atlas, showing the supratentorial cerebrovascular territories and the inter-territorial border-zones in a statistically rigorous way. The diffusion-weighted MRI lesion atlas is based on 1160 patients (67.0 ± 13.3 years old, 53.7% men) with acute (<1-week) cerebral infarction due to significant (>50%) stenosis or occlusion of a single large cerebral artery: anterior, middle, or posterior cerebral artery. We developed a software package enabling the transformation of our MR-based atlas into a re-oriented CT space corresponding to the axial slice orientations used in clinical practice. Infarct volumes are individually mapped to the three vascular territories on the CT template-set, generating brain maps showing the voxelwise frequency of infarct by the affected parent vessel. We then mapped the three vascular territories collectively, generating a dataset of Certainty-Index (CI) maps to reflect the likelihood of a voxel being a member of a specific vascular territory. Border-zones could be defined by using either relative infarct frequencies or CI differences. The topographic vascular territory atlas, revised for CT, will allow for easier and more accurate delineation of arterial territories and borders on CT images.

Solumbra thrombectomy as intravascular recanalization for treatment of acute ischemic stroke due to large cerebral artery occlusion

Objective To investigate the feasibility, effectiveness, and technical superiority of Solumbra thrombectomy for treatment of acute large cerebral artery occlusion stroke. Methods 32 patients who had acute large cerebral artery occlusion stroke and received mechanical thrombectomy in TEDA Hospital of Tianjin between January 2013 and August 2016, were divided into two groups: stent group(with conventional stent-retrievers, n=21)and Solumbra group(with Solumbra thrombectomy, n=11). Clinical characteristics, variables correlated with operation, and clinical outcomes were compared and analyzed retrospectively. Results There were no differences in basic clinical and radiographic parameters between stent group versus Solumbra group(all P>0.05). Moreover, there were no differences between Solumbra group versus Stent group in rates of embolus to new territory(18.2% vs.28.6%, P=0.425), in times of thrombectomy(2.2±1.0 vs.2.4±1.3, P=0.657), in non-symptomatic intracranial hemorrhage(18.2% vs.14.3%, P=0.572), in symptomatic intracranial hemorrhage(18.2% vs.9.5%, P=0.427), in TICI 2b/3 revascularization(81.8% vs.81.0%, P=0.670), in puncture-to-reperfusion time[(66.4±39.0)min vs.(51.6±34.5)min, P=0.279], and in NIHSS at 7 days(11.6±7.7 vs.11.3±7.2, P=0.925). A modified Rankin Scale(mRS ≤2)is a variable of recovery of function and good clinical outcome at 90 days.The levels of mRS were similar(P=0.490)between Solumbra and stent groups, but there was a tendency to higher rate of good clinical outcome at 90 days in Solumbra group(63.6%, 7/11)than in stent group(47.6%, 10/21). Conclusions Solumbra thrombectomy as intravascular revascularization technique is an effective and safe strategy for endovascular recanalization of acute large cerebral artery occlusion stroke.Compared with conventional Stent-Retriever thrombectomy, Solumbra thrombectomy has a good clinical outcome tendency at 90 days after operation. Key words: Brain infarction; Solumbra technique

Solitaire Stent in the Treatment of Acute Ischemic Stroke with Large Cerebral Artery Occlusion.

ObjectiveTo investigate the effect of mechanical thrombectomy with solitaire stent in the treatment of acute ischemic stroke with large cerebral artery occlusion.MethodsFifteen acute ischemic stroke patients with a proximal intracranial occlusion in the anterior circulation were included within 6 hours after symptom onset (unknown time of onset allowed in wake upstroke). Patients with a large infarct core or poor collateral circulation on computed tomography (CT) and CT angiography were excluded. All patients were measured by the National Institutes of Health Stroke Scale (NIHSS) before and 24 hours after the procedure. The primary outcomes were reperfusion at 24 hours and a Thrombolysis in Cerebral Infarction (TICI) score of 2b or 3 indicates successful reperfusion. Secondary outcomes included the functional score on the Modified Rankin Scale(MRS) and NIHSS score at 90 days. Good Functional Outcome (GFO), is defined as mRS0–2 at 90 days.ResultsThe preoperative TICI grading of these 15 patients were all level 0.14 patients were level 2b to level 3 after the thrombectomy, 1 ipsilateral cervical carotid occlusion patient failed recanalization.14 patients with reperfusion at 24 hours showed good early neurologic improvement. The MRS score of all the 14 patients were<2 point at 90 days. There were no obvious adverse reactions and complications in these patients after mechanical thrombectomy.ConclusionThe application of mechanical thrombectomy with solitaire stent for the treatment of acute ischemic stroke with large cerebral artery occlusion is safe and time-efficient, which could improve the recanalization rate, decrease or even eliminate the application of thrombolytic drugs and reduce the rate of intracranial hemorrhage. Awake stroke patient can also benefit from thrombectomy.

Endovascular Thrombectomy in Acute Ischemic Stroke: Outcome in Referred Versus Directly Admitted Patients

Endovascular mechanical thrombectomy (mTE) in acute ischemic stroke due to large cerebral artery occlusion is effective and safe. The procedure is currently offered by specialized hospitals. Physicians from smaller hospitals need to refer patients to stroke centers. Secondary referrals involve delays for transportation. Little is known about effects of distant referrals on outcome and complications as compared to direct admittance. To evaluate the effects of referral patterns on outcome and safety, we analyzed 941 patients with anterior circulation stroke receiving mTE between January 2010 and December 2015. Patients were divided into three groups: directly admitted patients (DAP), inner-city transfers (ICT) and long-distance referrals (LDR). We assessed (1)procedural parameters (2)frequency of good functional outcome (mRS ≤2 at 3months) and (3)mortality rates. Referrals had a significantly longer imaging-to-groin time compared to DAP (median 150min vs. 85min, p<0.001), the same was true for LDR vs. ICT (median 157min vs. 133.5min, p<0.001). Time to recanalization was significantly longer for referrals compared to DAP (median 348min vs. 260min, p<0.001). There was no significant difference in the frequency of good functional outcome (DAP 39.5%, ICT 35.1%, LDR 37.0%; p=0.709), all-cause mortality at day 90 (DAP 31.5%, ICT 23.0%, LDR 27.0%; p=0.212) and the rate of symptomatic intracranial hemorrhage (p=0.834). Timing remains a critical factor in acute ischemic stroke treatment by endovascular means. Long distance referral to specialized neurovascular centers with high recanalization rates, however, does allow for a good functional outcome in a significant number of patients.

Update of the Korean Clinical Practice Guidelines for Endovascular Recanalization Therapy in Patients with Acute Ischemic Stroke

Patients with severe stroke due to acute large cerebral artery occlusion are likely to be severely disabled or dead without timely reperfusion. Previously, intravenous tissue plasminogen activator (IV-TPA) within 4.5 hours after stroke onset was the only proven therapy, but IV-TPA alone does not sufficiently improve the outcome of patients with acute large artery occlusion. With the introduction of the advanced endovascular therapy, which enables more fast and more successful recanalization, recent randomized trials consecutively and consistently demonstrated the benefit of endovascular recanalization therapy (ERT) when added to IV-TPA. Accordingly, to update the recommendations, we assembled members of the writing committee appointed by the Korean Stroke Society, the Korean Society of Interventional Neuroradiology, and the Society of Korean Endovascular Neurosurgeons. Reviewing the evidences that have been accumulated, the writing members revised recommendations, for which formal consensus was achieved by convening a panel composed of 34 experts from the participating academic societies. The current guideline provides the evidence-based recommendations for ERT in patients with acute large cerebral artery occlusion regarding patient selection, treatment modalities, neuroimaging evaluation, and system organization.

Large field-of-view movement-compensated intrinsic optical signal imaging for the characterization of the haemodynamic response to spreading depolarizations in large gyrencephalic brains

Haemodynamic responses to spreading depolarizations (SDs) have an important role during the development of secondary brain damage. Characterization of the haemodynamic responses in larger brains, however, is difficult due to movement artefacts. Intrinsic optical signal (IOS) imaging, laser speckle flowmetry (LSF) and electrocorticography were performed in different configurations in three groups of in total 18 swine. SDs were elicited by topical application of KCl or occurred spontaneously after middle cerebral artery occlusion. Movement artefacts in IOS were compensated by an elastic registration algorithm during post-processing. Using movement-compensated IOS, we were able to differentiate between four components of optical changes, corresponding closely with haemodynamic variations measured by LSF. Compared with ECoG and LSF, our setup provides higher spatial and temporal resolution, as well as a better signal-to-noise ratio. Using IOS alone, we could identify the different zones of infarction in a large gyrencephalic middle cerebral artery occlusion pig model. We strongly suggest movement-compensated IOS for the investigation of the role of haemodynamic responses to SDs during the development of secondary brain damage and in particular to examine the effect of potential therapeutic interventions in gyrencephalic brains.

Heads Up! A Novel Provocative Maneuver to Guide Acute Ischemic Stroke Management

Background: A common dilemma in acute ischemic stroke management is whether to pursue recanalization therapy in patients with large vessel occlusions but minimal neurologic deficits. We describe and report preliminary experience with a provocative maneuver, i.e. 90-degree elevation of the head of bed for 30 min, which stresses collaterals and facilitates decision-making. Methods: A prospective cohort study of <7.5 h of acute anterior circulation territory ischemia patients with minimal deficits despite middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease. Results: Five patients met the study entry criteria. Their mean age was 78.4 years (range 65-93). All presented with substantial deficits (median NIHSS score 11, range 5-22), but improved while in supine position during initial imaging to normal or near-normal (NIHSS score 0-2). MRA showed persistent M1 MCA occlusions in 4, critical ICA stenosis or occlusion in 1, and substantial perfusion-diffusion mismatch in all. To evaluate the potential for eventual collateral failure, patients were placed in a head of bed upright posture. Mean arterial pressure and heart rate were unchanged. Two showed no neurologic worsening and were treated with supportive care with excellent final outcome. Three showed worsening, including recurrent hemiparesis and aphasia at the 6th, recurrent aphasia at the 23rd, and recurrent hemineglect at the 15th upright minute. These 3 underwent endovascular recanalization therapies with successful reperfusion and excellent final outcome. Conclusion: The ‘Heads Up' test may be a useful, simple maneuver to assess the risk of collateral failure and guide the decision to pursue recanalization therapy in acute cerebral ischemia patients with minimal deficits despite persisting large cerebral artery occlusion.

Update of the Korean Clinical Practice Guidelines for Endovascular Recanalization Therapy in Patients with Acute Ischemic Stroke.

Patients with severe stroke due to acute large cerebral artery occlusion are likely to be severely disabled or dead without timely reperfusion. Previously, intravenous tissue plasminogen activator (IV-TPA) within 4.5 hours after stroke onset was the only proven therapy, but IV-TPA alone does not sufficiently improve the outcome of patients with acute large artery occlusion. With the introduction of the advanced endovascular therapy, which enables more fast and more successful recanalization, recent randomized trials consecutively and consistently demonstrated the benefit of endovascular recanalization therapy (ERT) when added to IV-TPA. Accordingly, to update the recommendations, we assembled members of the writing committee appointed by the Korean Stroke Society, the Korean Society of Interventional Neuroradiology, and the Society of Korean Endovascular Neurosurgeons. Reviewing the evidences that have been accumulated, the writing members revised recommendations, for which formal consensus was achieved by convening a panel composed of 34 experts from the participating academic societies. The current guideline provides the evidence-based recommendations for ERT in patients with acute large cerebral artery occlusion regarding patient selection, treatment modalities, neuroimaging evaluation, and system organization.