Admission systolic blood pressure and effect of endovascular treatment in patients with ischaemic stroke: an individual patient data meta-analysis.

BACKGROUND: Current guidelines for ischaemic stroke treatment recommend a strict, but arbitrary, upper threshold of 185/110 mm Hg for blood pressure before endovascular thrombectomy. Nevertheless, whether admission blood pressure influences the effect of endovascular thrombectomy on outcome remains unknown. Our aim was to study the influence of admission systolic blood pressure (SBP) on functional outcome and on the effect of endovascular thrombectomy. METHODS: We used individual patient data from seven randomised controlled trials (MR CLEAN, ESCAPE, EXTEND-IA, SWIFT PRIME, REVASCAT, PISTE, and THRACE) that randomly assigned patients with anterior circulation ischaemic stroke to endovascular thrombectomy (predominantly using stent retrievers) or standard medical therapy (control) between June 1, 2010, and April 30, 2015. We included all patients for whom SBP data were available at hospital admission. The primary outcome was functional outcome (modified Rankin Scale) at 90 days. We assessed the association of SBP with outcome in both the endovascular thrombectomy group and the control group using multilevel regression analysis and tested for non-linearity and for interaction between SBP and effect of endovascular thrombectomy, taking into account treatment with intravenous thrombolysis. FINDINGS: We included 1753 patients (867 assigned to endovascular thrombectomy, 886 assigned to control) after excluding 11 patients for whom SBP data were missing. We found a non-linear association between SBP and functional outcome with an inflection point at 140 mm Hg (732 [42%] of 1753 patients had SBP <140 mm Hg and 1021 [58%] had SBP ≥140 mm Hg). Among patients with SBP of 140 mm Hg or higher, admission SBP was associated with worse functional outcome (adjusted common odds ratio [acOR] 0·86 per 10 mm Hg SBP increase; 95% CI 0·81-0·91). We found no association between SBP and functional outcome in patients with SBP less than 140 mm Hg (acOR 0·97 per 10 mm Hg SBP decrease, 95% CI 0·88-1·05). There was no significant interaction between SBP and effect of endovascular thrombectomy on functional outcome (p=0·96). INTERPRETATION: In our meta-analysis, high admission SBP was associated with worse functional outcome after stroke, but SBP did not seem to negate the effect of endovascular thrombectomy. This finding suggests that admission SBP should not form the basis for decisions to withhold or delay endovascular thrombectomy for ischaemic stroke, but randomised trials are needed to further investigate this possibility. FUNDING: Medtronic.

Efficacy of recanalization therapy for ischemic stroke: multicenter hospital network experience.

PURPOSE: Stroke is a leading cause of long-term disability with high mortality rate in the first year after the event. In Campania, mechanical thrombectomy treatment significantly increases in the last 3 years, as well as hospitals delivering acute stroke treatments. The aim of this study is to demonstrate how a full opening of our stroke network improves stroke management and stroked patients' survival in Campania. MATERIAL AND METHODS: In Federico II University Hospital of Naples acting as a HUB center of 7 peripheral SPOKE hospitals in regional territory, 68 patients with acute ischemic stroke were evaluated with NIHSS and m-RS clinical scores and neuroradiological ASPECT scores, from January 1 to December 31, 2021. At hospital discharge, NIHSS score and three months after m-RS score were re-assessed to evaluate the therapeutic effects. RESULTS: Forty-two of 68 patients (63%) admitted to our hub center had ischemic acute stroke at CT evaluation; 29 patients had ASPECT score > 7 (69%), and 6 a score < 7 (14%). At admission, NIHSS score mean value was 10.75, and m-RS score mean value was 0.74. At discharge, NIHSS score mean value was 7.09. After three months, m-RS score mean value was 0.74. DISCUSSION: The inter-company agreement between Federico II University and several peripheral hospitals allows an absolute and relative increase in endovascular mechanical thrombectomy and intravenous thrombolysis procedures, with a relative prevalence of mechanical thrombectomy. A regional implementation of the stroke multi-disciplinary care system is hardly needed to ensure the optimum treatment for the largest number of patients, improving patient's outcome.

Endovascular thrombectomy for basilar artery occlusion: translating research findings into clinical practice.

BACKGROUND: Basilar artery occlusion is a rare and severe condition. The effectiveness of endovascular thrombectomy in patients with basilar artery occlusion was unclear until recently, because these patients were excluded from most trials of endovascular thrombectomy for large-vessel occlusion ischaemic stroke. RECENT DEVELOPMENTS: The Basilar Artery International Cooperation Study (BASICS) and the Basilar Artery Occlusion Endovascular Intervention versus Standard Medical Treatment (BEST) trials, specifically designed to investigate the benefit of thrombectomy in patients with basilar artery occlusion, did not find significant evidence of a benefit of endovascular thrombectomy in terms of disability outcomes at 3 months after stroke. However, these trials suggested a potential benefit of endovascular thrombectomy in patients presenting with moderate-to-severe symptoms. Subsequently, the Endovascular Treatment for Acute Basilar Artery Occlusion (ATTENTION) and the Basilar Artery Occlusion Chinese Endovascular (BAOCHE) trials, which compared endovascular thrombectomy versus medical therapy within 24 h of onset, showed clear benefit of endovascular thrombectomy in reducing disability and mortality, particularly in patients with moderate-to-severe symptoms. The risk of intracranial haemorrhage with endovascular thrombectomy was similar to the risk in anterior circulation stroke. Thrombectomy was beneficial regardless of age, baseline characteristics, the presence of intracranial atherosclerotic disease, and time from symptom onset to randomisation. Therefore, the question of whether endovascular thrombectomy is beneficial in basilar artery occlusion now appears to be settled in patients with moderate-to-severe symptoms, and endovascular thrombectomy should be offered to eligible patients. WHERE NEXT?: Key outstanding issues are the potential benefits of endovascular thrombectomy in patients with mild symptoms, the use of intravenous thrombolysis in an extended time window (ie, after 4·5 h of symptom onset), and the optimal endovascular technique for thrombectomy. Dedicated training programmes and automated software to assist with the assessment of imaging prognostic markers could be useful in the selection of patients who might benefit from endovascular thrombectomy. Large international research networks should be built to address knowledge gaps in this field and allow the conduct of clinical trials with fast and consecutive enrolment and a diverse ethnic representation.

Effect of direct endovascular treatment versus standard bridging therapy in large artery anterior circulation stroke (DEVT): 18-month follow-up of a randomized controlled trial.

BACKGROUND: Two trials in Chinese population showed that endovascular treatment (EVT) alone was noninferior to alteplase follow by EVT at 90 days. However, results of long-term clinical outcomes remain unknown. We reported the results of prespecified 18-month analysis of the DEVT trail. MATERIALS AND METHODS: We assessed clinical outcomes 18 months after patients were randomly assigned to receive EVT alone or bridging therapy for acute ischemic stroke (AIS). The primary outcome was the proportion of functional independence [modified Rankin scale (mRS), 0-2] at 18 months. Secondary outcomes included all-cause mortality and the quality of life at 18 months as measured by means of a health utility index according to the European Quality of Life 5-Dimension 5-level scale (EQ-5D-5L). Kaplan-Meier event curves were used to investigate the risk of mortality in participants with EVT alone or bridging therapy. RESULTS: Among 234 patients (EVT alone, n = 116; bridging therapy, n = 118) in the DEVT trial, only 231 (98.7%) patients were extended follow-up to 18 months. A total of 60 (51.7%) patients in the EVT alone achieved functional independence vs 56 (47.5%) patients in the bridging therapy (difference, 4.3%; 1-sided 97.5% CI, - 8.4% to ∞, P for noninferiority =0.014). No significant between-group difference was detected in EQ-5D-5L score (0.81 vs 0.73; difference, 0; 95% CI, 0 to 0.005). The cumulative mortality was 27.6% in the EVT alone and 28.8% in the bridging therapy. CONCLUSION: At 18 months follow-up, EVT alone was noninferior to bridging therapy regarding favorable functional outcome in patients with AIS. TRIAL REGISTRATION: Trial was registered on Chinese Clinical Trial Registry (ChiCTR-IOR-17013568) on 27/11/2017.

Predictors of outcome after endovascular treatment for tandem occlusions: a single center retrospective analysis.

BACKGROUND: The endovascular treatment procedure in tandem occlusions (TO) is complex compared to single occlusion (SO) and optimal management remains uncertain. The aim of this study was to identify clinical and procedural factors that may be associated to efficacy and safety in the management of TO and compare functional outcome in TO and SO stroke patients. METHODS: This is a retrospective single center study of medium (MeVO) and large vessel occlusion (LVO) of the anterior circulation. Clinical, imaging, and interventional data were analyzed to identify predictive factors for symptomatic intracranial hemorrhage (sICH) and functional outcome after endovascular treatment (EVT) in TO. Functional outcome in TO and SO patients was compared. RESULTS: Of 662 anterior circulation stroke patients with MeVO and LVO stroke, 90 (14%) had TO. Stenting was performed in 73 (81%) of TO patients. Stent thromboses occurred in 8 (11%) patients. Successful reperfusion with modified thrombolysis in cerebral infarction (mTICI) ≥ 2b was achieved in 82 (91%). SICH occurred in seven (8%). The strongest predictors for sICH were diabetes mellitus and number of stent retriever passes. Good functional clinical outcome (mRS ≤ 2) at 90-day follow up was similar in TO and SO patients (58% vs 59% respectively). General anesthesia (GA) was associated with good functional outcome whereas hemorrhage in the infarcted tissue, lower mTICI score and history of smoking were associated with poor outcome. CONCLUSIONS: The risk of sICH was increased in patients with diabetes mellitus and those with extra stent-retriever attempts. Functional clinical outcomes in patients with TO were comparable to patients with SO.

In basilar-artery occlusion stroke, thrombectomy improved functional outcome at 90 d but increased ICH.

SOURCE CITATION: Tao C, Nogueira RG, Zhu Y, et al. Trial of endovascular treatment of acute basilar-artery occlusion. N Engl J Med. 2022;387:1361-72. 36239644.

In basilar-artery occlusion stroke, thrombectomy improved functional outcomes without increasing ICH.

SOURCE CITATION: Jovin TG, Li C, Wu L, et al. Trial of thrombectomy 6 to 24 hours after stroke due to basilar-artery occlusion. N Engl J Med. 2022;387:1373-84. 36239645.

First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study.

OBJECTIVE: We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes. MATERIALS AND METHODS: In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months. RESULTS: Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004). CONCLUSION: Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Current advances in endovascular treatment.

PURPOSE OF REVIEW: Endovascular thrombectomy (EVT) is the most beneficial reperfusion therapy for acute ischemic stroke. Currently, much effort is done to promote trials examining EVT efficacy and safety in various conditions not included in the main randomized controlled trials established the superiority of EVT. This review summarizes the current advances of EVT patients' selection and periprocedural management. RECENT FINDINGS: Recent evidence points to beneficial effect of EVT among patients with relatively large ischemic core, premorbid independent nonagenarians and basilar artery occlusion, and suggest that intravenous thrombolysis bridging treatment is associated with better reperfusion rates. Ongoing trials currently examine EVT efficacy and safety in distal vessel occlusions and in large vessel occlusion with low NIHSS. Current evidence also support use of general anaesthesia and avoid postprocedural extremely low or high blood pressure as well as haemodynamic instability. SUMMARY: The field of EVT is rapidly evolving. The results of recent trials have dramatically increased the indications for EVT, with many ongoing trials examining further indications.

Decompressive Hemicraniectomy in the Stroke Patient.

Decompressive hemicraniectomy (DHC) is a life-saving procedure involving removal of large portions of the skull to relieve intracranial pressure in patients with space occupying cerebral edema such as traumatic brain injury (TBI) and stroke. Although the procedure has been shown to decrease mortality in patients, the risk of severe disability is significant. Quality of life, not just survival, following DHC has emerged as an important consideration when the decision is made to perform a DHC.

A Canine Surgical Model of Stroke by Minimally Invasive Occlusion of the Proximal Middle Cerebral Artery.

In this study, a model of ischemic stroke by surgical proximal middle cerebral artery (MCA) occlusion was developed on 10 beagle dogs. The advantages of this model are the transtemporal approach and a minimally invasive surgical procedure. Dogs were randomly assigned to two groups: sham-operated (proximal MCA exposure without occlusion) and experimental (permanent proximal MCA occlusion) groups. Different evaluation methods were used to assess the consequences of MCA occlusion in dogs, including neurobehavioral tests, MRI, and immunohistochemical staining. Clear signs of cerebral infarction associated with the region supplied by MCA were confirmed and the model showed good repeatability and consistency. The model can serve as an appropriate large animal model to improve the translation of stroke therapeutics research from the laboratory to the clinical practice.

Outcomes of decompressive craniectomy for large territory cerebral infarction with and without prior reperfusion: a multicentre retrospective review.

PURPOSE: Reperfusion therapy has greatly improved outcomes of ischaemic stroke but remains associated with haemorrhagic conversion and early deterioration in a significant proportion of patients. Outcomes in terms of function and mortality are mixed and the evidence for decompressive craniectomies (DC) in this context remains sparse. We aim to investigate the clinical efficacy of DC in this group of patients compared to those without prior reperfusion therapy. METHODS: A multicentre retrospective study was conducted between 2005 and 2020, and all patients with DC for large territory infarctions were included. Outcomes in terms of inpatient and long-term modified Rankin scale (mRS) and mortality were assessed at various time points and compared using both univariable and multivariable analyses. Favourable mRS was defined as 0-3. RESULTS: There were 152 patients included in the final analysis. The cohort had a mean age of 57.5 years and median Charlson comorbidity index of 2. The proportion of preoperative anisocoria was 15.1%, median preoperative Glasgow coma scale was 9, the ratio of left-sided stroke was 40.1%, and ICA infarction was 42.8%. There were 79 patients with prior reperfusion and 73 patients without. After multivariable analysis, the proportion of favourable 6-month mRS (reperfusion, 8.2%; no reperfusion, 5.4%) and 1-year mortality (reperfusion, 26.7%; no reperfusion, 27.3%) were similar in both groups. Subgroup analysis of thrombolysis and/or thrombectomy against no reperfusion was also unremarkable. CONCLUSION: Reperfusion therapy prior to DC performed for large territory cerebral infarctions does not affect the functional outcome and mortality in a well-selected patient population.

Reperfusion Treatments in Disabling Versus Nondisabling Mild Stroke due to Anterior Circulation Vessel Occlusion.

BACKGROUND: The benefit of distinguishing between disabling versus nondisabling deficit in mild acute ischemic stroke due to endovascular thrombectomy-targetable vessel occlusion (EVT-tVO; including anterior circulation large and medium-vessel occlusion) is unknown. We compared safety and efficacy of acute reperfusion treatments in disabling versus nondisabling mild EVT-tVO. METHODS: From the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register, we included consecutive acute ischemic stroke patients (2015-2021) treated within 4.5 hours, with full NIHSS items availability and score ≤5, evidence of intracranial internal carotid artery, M1, A1-2, or M2-3 occlusion. After propensity score matching, we compared efficacy (3-month modified Rankin Scale score of 0-1, modified Rankin Scale score of 0-2, and early neurological improvement) and safety (nonhemorrhagic early neurological deterioration, any intracerebral or subarachnoid hemorrhage, symptomatic intracranial hemorrhage, and death at 3-month) outcomes in disabling versus nondisabling patients-adopting an available definition. RESULTS: We included 1459 patients. Propensity score matched analysis of disabling versus nondisabling EVT-tVO (n=336 per group) found no significant differences in efficacy (modified Rankin Scale score 0-1: 67.4% versus 71.5%, P=0.336; modified Rankin Scale score 0-2: 77.1% versus 77.6%, P=0.895; early neurological improvement: 38.3% versus 44.4%, P=0.132) and safety (nonhemorrhagic early neurological deterioration: 8.5% versus 8.0%, P=0.830; any intracerebral hemorrhage or subarachnoid hemorrhage: 12.5% versus 13.3%, P=0.792; symptomatic intracranial hemorrhage: 2.6% versus 3.4%, P=0.598; and 3-month death: 9.8% versus 9.2%, P=0.844) outcomes. CONCLUSIONS: We found similar safety and efficacy outcomes after acute reperfusion treatment in disabling versus nondisabling mild EVT-tVO; our findings suggest to adopt similar acute treatment approaches in the 2 groups. Randomized data are needed to clarify the best reperfusion treatment in mild EVT-tVO.

Histologically interpretable clot radiomic features predict treatment outcomes of mechanical thrombectomy for ischemic stroke.

PURPOSE: Radiomics features (RFs) extracted from CT images may provide valuable information on the biological structure of ischemic stroke blood clots and mechanical thrombectomy outcome. Here, we aimed to identify RFs predictive of thrombectomy outcomes and use clot histomics to explore the biology and structure related to these RFs. METHODS: We extracted 293 RFs from co-registered non-contrast CT and CTA. RFs predictive of revascularization outcomes defined by first-pass effect (FPE, near to complete clot removal in one thrombectomy pass), were selected. We then trained and cross-validated a balanced logistic regression model fivefold, to assess the RFs in outcome prediction. On a subset of cases, we performed digital histopathology on the clots and computed 227 histomic features from their whole slide images as a means to interpret the biology behind significant RF. RESULTS: We identified 6 significantly-associated RFs. RFs reflective of continuity in lower intensities, scattered higher intensities, and intensities with abrupt changes in texture were associated with successful revascularization outcome. For FPE prediction, the multi-variate model had high performance, with AUC = 0.832 ± 0.031 and accuracy = 0.760 ± 0.059 in training, and AUC = 0.787 ± 0.115 and accuracy = 0.787 ± 0.127 in cross-validation testing. Each of the 6 RFs was related to clot component organization in terms of red blood cell and fibrin/platelet distribution. Clots with more diversity of components, with varying sizes of red blood cells and fibrin/platelet regions in the section, were associated with RFs predictive of FPE. CONCLUSION: Upon future validation in larger datasets, clot RFs on CT imaging are potential candidate markers for FPE prediction.

Angioplasty, stenting, or both - rescue maneuvers and reperfusion after endovascular therapy for intracranial atherosclerosis-related occlusion.

PURPOSE: Data concerning reperfusion strategies of intracranial atherosclerosis-related occlusion (ICARO) and clinico-angiographic outcomes remain scarce, particularly in Caucasians. We aim to compare the reperfusion rate and functional outcome between reperfusion strategies in the setting of the ICARO. METHODS: Retrospective analysis of prospectively maintained endovascular thrombectomy (EVT) registries at three high-volume stroke centers were retrospectively analyzed for consecutive ICARO patients from January 2015 to December 2019. We defined ICARO as any fixed high-degree (> 70%) focal narrowing or stenosis of any degree with a perpetual tendency for reocclusion. We categorized reperfusion strategies into four groups: EVT [group 1], balloon angioplasty [(BAp), group 2], placement of self-expandable stents [(SES), group 3], and BAp combined with implantation of SES; or direct placement of balloon mounted stents (BMS) [(BAp-SES/BMS), group 4]. We evaluated the association with the successful reperfusion [mTICI 2b - 3] and favorable outcome [mRS 0-2] with logistic regression analysis. RESULTS: Out of 2550 EVT, 124 patients (median age, 70 (61-80) years; 76 men) with ICARO and 130 reperfusion attempts [36 EVT, 38 BAp, 17 SES, and 39 BAp + SES/BMS] were analyzed. SES implantation showed the highest frequency of post-procedural symptomatic intracranial hemorrhage [(18%, 3/17), p = .03]; however, we observed no significant differences in the mortality rate. Overall, we achieved successful reperfusion in 71% (92/130) and favorable outcomes in 42% (52/124) of the patients. BAp + SES/BMS was the only independent predictor of the final successful reperfusion [aOR, 4.488 (95% CI, 1.364-14.773); p = .01], which was significantly associated with the 90-day favorable outcome [aOR, 10.837 (95% CI, 3.609-32.541); p = < .001] after adjustment for confounding variables between the reperfusion strategies. CONCLUSION: Among patients with ICARO, the rescue angioplasty stenting effectively contributed to higher odds of successful reperfusion with no increased risk for intracranial hemorrhage.

Outcomes after endovascular mechanical thrombectomy for low compared to high National Institutes of Health Stroke Scale (NIHSS): A multicenter study.

OBJECTIVE: The role of endovascular mechanical thrombectomy (MT) in patients presenting with "minor" stroke is uncertain. We aimed to compare outcomes after MT for ischemic stroke patients presenting with National Institutes of Health Stroke Scale (NIHSS) 5 and - within the low NIHSS cohort - identify predictors of a favorable outcome, mortality, and symptomatic intracranial hemorrhage (ICH). METHODS: We retrospectively analyzed a prospectively maintained, international, multicenter database. RESULTS: The study cohort comprised a total of 7568 patients from 29 centers. NIHSS was low (<5) in 604 patients (8%), and > 5 in 6964 (92%). Patients with low NIHSS were younger (67 + 14.8 versus 69.6 + 14.7 years, p < 0.001), more likely to have diabetes (31.5% versus 26.9%, p = 0.016), and less likely to have atrial fibrillation (26.6% versus 37.6%, p < 0.001) compared to those with higher NIHSS. Radiographic outcomes (TICI > 2B 84.6% and 84.3%, p = 0.412) and complication rates (8.1% and 7.2%, p = 0.463) were similar between the low and high NIHSS groups, respectively. Clinical outcomes at every follow up interval, including NIHSS at 24 h and discharge, and mRS at discharge and 90 days, were better in the low NIHSS group, however patients in the low NIHSS group experienced a relative decline in NIHSS from admit to discharge. Mortality was lower in the low NIHSS group (10.4% versus 24.5%, p < 0.001). CONCLUSIONS: Relative to patients with high NIHSS, MT is safe and effective for stroke patients with low NIHSS, and it is reasonable to offer it to appropriately selected patients presenting with minor stroke symptoms. Our findings justify efforts towards a randomized trial comparing MT versus medical management for patients with low NIHSS.

Reperfusion injury in acute ischemic stroke: Tackling the irony of revascularization.

Reperfusion injury is an unfortunate consequence of restoring blood flow to tissue after a period of ischemia. This phenomenon can occur in any organ, although it has been best studied in cardiac cells. Based on cardiovascular studies, neuroprotective strategies have been developed. The molecular biology of reperfusion injury remains to be fully elucidated involving several mechanisms, however these mechanisms all converge on a similar final common pathway: blood brain barrier disruption. This results in an inflammatory cascade that ultimately leads to a loss of cerebral autoregulation and clinical worsening. In this article, the authors present an overview of these mechanisms and the current strategies being employed to minimize injury after restoration of blood flow to compromised cerebral territories.

Predictive value of computed tomography perfusion for acute ischemic stroke patients with ASPECTS < 6 in an early time window.

OBJECTIVE: The standard for computed tomography perfusion (CTP) assessment has not been well established in early acute ischemic stroke (AIS). We aimed to examine the prognostic factors for good outcomes in patients who received CTP, with an Alberta Stroke Program Early CT Score (ASPECTS) < 6 after endovascular thrombectomy (EVT) in the early time window (0-6 h). METHODS: We retrospectively reviewed 59 patients who met the criteria from October 2019 to April 2021. Based on the modified Rankin Score (mRS) at 90 days, the patients were divided into a good outcome group (mRS 0-2) and a poor outcome group (mRS 3-6). Baseline and procedural characteristics were collected for unilateral and multivariate regression analyses to explore the influencing factors for good outcomes. RESULTS: Of the 59 patients included, good outcomes were observed in 21 (35.6%). Multivariate logistic regression analysis showed that smaller ischemic core volume (odds ratio [OR]: 0.950; 95% CI: 0.908-0.994; P = 0.026), lower National Institutes of Health Stroke Scale (NIHSS) score (OR: 0.750; 95% CI: 0.593-0.949; P = 0.017) and shorter stroke onset to reperfusion time (ORT) (OR: 0.981; 95% CI: 0.966-0.996; P = 0.016) were independent predictors for good outcomes at 90 days. CONCLUSION: Smaller ischemic core volume based on CTP, lower NIHSS score and shorter ORT were significant independent predictors of good outcomes in patients with ASPECTS < 6 in the early time window after EVT.

Spatial accuracy of computed tomography perfusion to estimate the follow-up infarct on diffusion-weighted imaging after successful mechanical thrombectomy.

BACKGROUND: Volumetric accuracy of using computed tomography perfusion (CTP) to estimate the post-treatment infarct in stroke patients with successful recanalization after mechanical thrombectomy (MT) has been studied a lot, however the spatial accuracy and its influence factors has not been fully investigated. METHODS: This retrospective study reviewed the data from consecutive anterior large vessel occlusion (LVO) patients who had baseline CTP, successful recanalization after MT, and post-treatment diffusion-weighed imaging (DWI). Ischemic core on baseline CTP was estimated using relative cerebral blood flood (CBF) of < 30%. The infarct area was outlined manually on post-treatment DWI, and registered to CTP. Spatial agreement was assessed using the Dice similarity coefficient (DSC) and average Hausdorff distance. According to the median DSC, the study population was dichotomized into high and low Dice groups. Univariable and multivariable regression analyses were used to determine the factors independently associated with the spatial agreement. RESULTS: In 72 included patients, the median DSC was 0.26, and the median average Hausdorff distance was 1.77 mm. High Dice group showed significantly higher median ischemic core volume on baseline CTP (33.90 mL vs 3.40 mL, P < 0.001), lower proportion of moderate or severe leukoaraiosis [27.78% vs 52.78%, P = 0.031], and higher median infarct volume on follow-up DWI (51.17 mL vs 9.42 mL, P < 0.001) than low Dice group. Ischemic core volume on baseline CTP was found to be independently associated with the spatial agreement (OR, 1.092; P < 0.001). CONCLUSIONS: CTP could help to spatially locate the post-treatment infarct in anterior LVO patients who achieving successful recanalization after MT. Ischemic core volume on baseline CTP was independently associated with the spatial agreement.