Decreased Quantitative Cerebral Blood Volume Is Associated With Poor Outcomes in Large Core Patients.

BACKGROUND: Recent large core trials have highlighted the effectiveness of mechanical thrombectomy (MT) in acute ischemic stroke with large vessel occlusion. Variable perfusion-imaging thresholds and poor Alberta Stroke Program Early Computed Tomography Score reliability underline the need for more standardized, quantitative ischemia measures for MT patient selection. We aimed to identify the computed tomography perfusion parameter most strongly associated with poor outcomes in patients with acute ischemic stroke-large vessel occlusion with significant ischemic cores. METHODS: In this study from 2 comprehensive stroke centers from 2 comprehensive stroke centers within the Johns Hopkins Medical Enterprise (Johns Hopkins Hospita-East Baltimore and Bayview Medical Campus) from July 29, 2019 to January 29, 2023 in a continuously maintained database, we included patients with acute ischemic stroke-large vessel occlusion with ischemic core volumes defined as relative cerebral blood flow <30% and ≥50 mL on computed tomography perfusion or Alberta Stroke Program Early Computed Tomography Score <6. We used receiver operating characteristics to find the optimal cutoff for parameters like cerebral blood volume (CBV) <34%, 38%, 42%, and relative cerebral blood flow >20%, 30%, 34%, 38%, and time-to-maximum >4, 6, 8, and 10 seconds. The primary outcome was unfavorable outcomes (90-day modified Rankin Scale score 4-6). Multivariable models were adjusted for age, sex, diabetes, baseline National Institutes of Health Stroke Scale, intravenous thrombolysis, and MT. RESULTS: We identified 59 patients with large ischemic cores. A receiver operating characteristic curve analysis showed that CBV<42% ≥68 mL is associated with unfavorable outcomes (90-day modified Rankin Scale score 4-6) with an area under the curve of 0.90 (95% CI, 0.82-0.99) in the total and MT-only cohorts. Dichotomizing at this CBV threshold, patients in the ≥68 mL group exhibited significantly higher relative cerebral blood flow, time-to-maximum >8 and 10 seconds volumes, higher CBV volumes, higher HIR, and lower CBV index. The multivariable model incorporating CBV<42% ≥68 mL predicted poor outcomes robustly in both cohorts (area under the curve for MT-only subgroup was 0.87 [95% CI, 0.75-1.00]). CONCLUSIONS: CBV<42% ≥68 mL most effectively forecasts poor outcomes in patients with large-core stroke, confirming its value alongside other parameters like time-to-maximum in managing acute ischemic stroke-large vessel occlusion.

Effect of Intravenous Thrombolysis and Mechanical Thrombectomy on the Incidence of Acute Symptomatic Seizure and Post-Stroke Epilepsy in Patients with Acute Large-Vessel Occlusion.

Objective: Reperfusion therapy, such as intravenous tissue-plasminogen activator (IV-tPA) and mechanical thrombectomy (MT) for acute ischemic stroke, may increase the incidence of acute symptomatic seizure (ASS) and post-stroke epilepsy (PSE). This study aimed to analyze the effect and predictors of reperfusion therapy for ASS and PSE limited to large-vessel occlusions (LVOs). Methods: This retrospective study classified 237 subjects with LVO into four groups: (1) IV-tPA + MT+ (n = 74 cases, (2) MT only (n = 82), (3) tissue-plasminogen activator (tPA) only (n = 28), and (4) IV-tPA - MT- (n = 53). The incidences of ASS and PSE were assessed. Potential predictors, such as etiology, functional disability, neuroimaging findings, and the SeLECT score, were statistically analyzed. Results: There were 12 (5.1%) subjects with ASS and 10 subjects (4.2%) with PSE. The IV-tPA and MT groups had significantly high reperfusion rates, with a Thrombolysis in Cerebral Infarction score ≥2c (p = 0.01) but there were no significant differences in the increases of hemorrhagic transformation, ASS, and PSE. An Alberta Stroke Program Early Computed Tomography Score <6 was a significant predictor of ASS (p = 0.01), and an infarct volume >60 ml was a significant predictor of PSE (p = 0.01). Conclusion: Reperfusion therapy for acute LVO was not found to increase the risk of ASS and PSE. Large-sized infarctions should be treated with care in PSE.

A technique for prevention of posterior stroke during urgent revascularization of an acutely ischemic left upper extremity.

Upper extremity acute limb ischemia (ALI) owing to obstruction proximal to the vertebral artery poses the risk of posterior stroke during intervention. We describe a case of upper extremity ALI secondary to thrombosis of the proximal left subclavian artery with thromboembolic occlusion at the brachial bifurcation. The patient underwent a hybrid procedure of open thromboembolectomy with endovascular vertebral artery embolic protection. The patient's distal pulses and upper extremity function returned to baseline, without evidence of posterior stroke. A literature review revealed limited reports of the use of cerebral embolic protection in the setting of emergent thromboembolectomy for upper extremity ALI.

Should they stay or should they go? Stroke transfers across a hospital network pre- and post-implementation of an automated image interpretation and communication platform.

BACKGROUND: A key decision facing nonthrombectomy capable (spoke) hospitals is whether to transfer a suspected large vessel occlusion (LVO) patient to a comprehensive stroke center (CSC). In a retrospective cohort study, we investigated the rate of transfers resulting in endovascular thrombectomy (EVT) and associated costs before and after implementation of an artificial intelligence (AI)-based software. METHODS: All patients with a final diagnosis of acute ischemic stroke presenting across a five-spoke community hospital network in affiliation with a CSC were included. The Viz LVO (Viz.ai, Inc.) software was implemented across the spokes with image sharing and messaging between providers across sites. In a cohort of patients before (pre-AI, December 2018-October 2020) and after (post-AI, October 2020-August 2022) implementation, we compared the EVT rate among ischemic stroke patients transferred out of our health system to the CSC. Secondary outcomes included the EVT rate based on spoke computed tomography angiography (CTA) and estimated transfer costs. RESULTS: A total of 3113 consecutive eligible patients (mean age 71 years, 50% female) presented to the spoke hospitals with 162 transfers pre-AI and 127 post-AI. The rate of transfers treated with EVT significantly increased (32.1% pre-AI vs. 45.7% post-AI, p = 0.02). There was a sharp increase in CTA use post-AI at the spoke hospitals for all patients and transfers that likely contributed to the increased EVT transfer rate, but prior spoke CTA use alone was not sufficient to account for all improvement in EVT transfer rate (37.2% pre-AI vs. 49.2% post-AI, p = 0.12). In a binary logistic regression model, the odds of an EVT transfer in the intervention period were 1.85 greater as compared to preintervention (adjusted odds ratio 1.85, 95% confidence interval 1.12-3.06). The decrease in non-EVT transfers resulted in an estimated annual benefit of $206,121 in spoke revenue and $119,921 in payor savings (all US dollars). CONCLUSIONS: The implementation of an automated image interpretation and communication platform was associated with increased CTA use, more transfers treated with EVT, and potential economic benefits.

A comparison of conscious sedation and local anesthesia for thrombectomy in acute ischemic stroke: a multicenter study.

Introduction: Ischemic cerebrovascular disease (ICVD) is a serious health problem in which brain tissue suffers from hypoxic damage due to obstruction in cerebral vessels. Mechanical thrombectomy is a commonly used method in the treatment of these patients. However, the effects of local anesthesia (LA) and conscious sedation (CS) during thrombectomy are still unclear. We evaluated whether there was a relationship between the two anesthesia regimens in terms of 90-day modified Rankin Scale (mRS) scores. Methods: In this study, a retrospective observational study was conducted to evaluate the effects of LA and CS used during mechanical thrombectomy in four comprehensive stroke centers among ICVD patients. Patients were divided into the LA group and the CS group. Statistical analysis was performed before and after 1:1 matching under propensity score matching (PSM) analysis. The primary outcome measure was an mRS score of 0-2 at 90 days. Secondary outcomes were procedure times, recanalization rates, symptomatic and asymptomatic hemorrhage rates, and procedural complications. Results: A total of 193 patients (118 patients with LA and 75 patients with CS) were included in the final analysis before PSM. After 1:1 PSM, 98 patients-49 patients from each group-were included in the study. There was no difference in clinical outcomes between the LA- and CS-applied groups (p = 0.543). When blood pressure (BP) values at follow-up after endovascular treatment (EVT) were compared, the lowest systolic and lowest diastolic BP were found to be lower in the CS group (p = 0.001 and p = 0.009). There was no significant difference between the two groups in terms of recanalization rates, symptomatic intracranial hemorrhage (sICH) rates, 90-day mRS, and procedure-related complication rates (p = 0.617, p = 0.274, p = 0.543, and p = 1.000). Conclusion: This study did not reveal the superiority of CS applied during EVT on 90-day mRS, sICH, recanalization rates, or procedural complications. However, the risk of developing hypotension during the CS application was found to be high.

Timing, type, and impact of thromboembolic events caused by flow diversion: a 10-year experience.

OBJECTIVE: Thromboembolic (TE) events are among the most feared complications after flow diversion (FD) and have been reported to occur even with adequate dual antiplatelet therapy. Herein, the authors characterize thrombotic and embolic events that developed after FD, focusing on the morbidity of each of these events and the predisposing factors associated with their development. METHODS: A retrospective analysis of aneurysms treated with FD at a single institution in the US between 2013 and 2023 was performed. The authors documented the emergence of intraprocedural and postoperative TE events. A survival analysis and a Cox regression model was conducted to identify predictors associated with these events. RESULTS: The authors included 651 procedures performed in 591 patients to treat 746 aneurysms. TE events occurred in 38 of the procedures performed (5.8%), causing permanent deficit in 20 patients and death in 4 patients. Eleven cases presented with acute stent thrombosis, 11 with large-vessel occlusion, and 9 with perforator strokes. At a median follow-up of 9.5 months, 73.0% of patients with an ischemic event had a modified Rankin Scale score ≤ 2. Three of the deaths were secondary to occlusion at the basilar trunk and vertebral artery. In patients with TE events in the anterior circulation, 7 of 11 patients with middle cerebral artery occlusion and 9 of 12 patients with internal carotid artery occlusion achieved independence. Time-to-event Cox regression analysis demonstrated that TE events were more frequent in patients exhibiting aspirin resistance (hazard ratio 2.66; 95% CI 1.10-6.70). CONCLUSIONS: TE events after FD result from multiple factors, including age, aneurysm characteristics, aneurysm location, antiplatelet resistance, and procedural factors. In our cohort, we found the highest morbidity for patients with TE events presenting with large-vessel occlusion at the middle cerebral artery, and vertebrobasilar system.

Early Recanalization after Tenecteplase versus Alteplase: Experience in a Large Stroke Network.

INTRODUCTION: Previously published data are conflicting regarding the ability of tenecteplase versus alteplase to produce early recanalization of an intracranial large vessel occlusion. We compared the performance of each thrombolytic in a stroke network. METHODS: We queried our prospectively collected code stroke registry for basilar, internal carotid, or proximal middle cerebral artery occlusion patients treated with intravenous thrombolysis from 11/17/2021-9/16/2023. The primary outcome was early recanalization, defined using angiographic or clinical criteria. Secondary and safety outcomes included 90-day functional independence and symptomatic intracranial hemorrhage. A multivariable regression analysis was performed to determine independent associations with the primary outcome. RESULTS: 233 patients, with mean age 66.9 (16.6) years and median National Institutes of Health Stroke Scale score 15 (10-21), were included. One-hundred twenty-four of 233 (53.2%) patients were treated with alteplase while 109/233 (46.8%) were treated with tenecteplase. Endovascular thrombectomy was performed in 82% of subjects. Early recanalization rates were similar between the groups (alteplase 22.6%, tenecteplase 14.7%; p=0.14), as were rates of 90-day independent neurological function, symptomatic intracranial hemorrhage, and mortality. Patients with an internal carotid artery occlusion or with higher presenting stroke severity were less likely to achieve early recanalization. CONCLUSIONS: Tenecteplase and alteplase have similar rates of early recanalization, 90-day functional independence, and safety outcomes in large vessel occlusion patients. Occlusion site and stroke severity predict response to thrombolysis. Future studies may investigate other factors associated with a positive response to thrombolytics as expanded treatment indications are explored.

Treatment of giant cell arteritis with ultra-short glucocorticoids and tocilizumab: results from the extension of the TOPAZIO study.

OBJECTIVES: To assess the maintenance of efficacy of one year of tocilizumab (TCZ) monotherapy after its discontinuation in large vessel-GCA (LV-GCA). METHODS: 17 patients with active LV-GCA were previously treated with 3 boluses of intravenous methylprednisone and weekly subcutaneous TCZ in monotherapy for 52 weeks. Patients in relapse-free clinical remission at week 52 discontinued TCZ and entered part two, which was a 26-week observational follow-up period. PET/CT was performed in all patients at the end of the 26-week observational period (week 78). End points were the variation in PET vascular activity score (PETVAS) at week 78 compared with baseline and with week 52, and the proportion of patients with relapse-free clinical remission at week 78 and at the end of the follow-up. RESULTS: Compared with baseline, a significant reduction in PETVAS was observed at week 78, mean (95% CI) change -6.6 (-9.5 to -3.7). However, compared with week 52, PETVAS significantly increase 6 months after TCZ discontinuation (week 78), mean (95% CI) change 4.6 (0.7-8.5). The proportion of patients with relapse-free clinical remission at weeks 78 and at the end of the follow-up (median time from TCZ discontinuation 148 weeks) was 11/17 (65%, 95% CI 38-86) and 8/17 (47%, 95% CI 23-72), respectively. Age and sex-adjusted HR (95% CI) for each unit increase of PETVAS indicating subsequent relapse was 1.36 (0.92-2.00). CONCLUSIONS: One year of TCZ monotherapy was effective in maintaining drug-free clinical remission in LV-GCA. Changes in PETVAS early after TCZ discontinuation may predict subsequent relapses. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT05394909.

Collateral flow and pulsatility during large vessel occlusions: insights from a quantitative in vitro study.

Acute ischemic stroke caused by large vessel occlusions is being increasingly treated with neurovascular interventions. The hemodynamics within the collateral system of the circle of Willis (CoW) hemodynamics play a fundamental role in therapy success. However, transient in vivo data on pathological collateral flow during large vessel occlusions are not available. Moreover, there are no flow models that accurately simulate the hemodynamic conditions in the CoW during large vessel occlusions. We used a circulatory loop to generate highly reproducible cerebrovascular-like flows and pressures and used non-invasive flow visualization and high-resolution flow and pressure measurements to acquire detailed, time-dependent hemodynamics inside an anatomical phantom of the CoW. After calibrating a physiological reference case, we induced occlusions in the 1. middle cerebral artery, 2. terminal carotid artery, and 3. basilar artery; and measured the left posterior communicating artery flow. Mean arterial pressure and pulse pressure remained unchanged in the different occlusion cases compared to the physiological reference case, while total cerebral flow decreased by up to 19%. In all three occlusion cases, reversed flow was found in the left posterior communicating artery compared to the reference case with different flow magnitudes and pulsatility index values. The experimental results were compared with clinical findings, demonstrating the capability of this realistic cerebrovascular flow setup. This novel cerebrovascular flow setup opens the possibility for investigating different topics of neurovascular interventions under various clinical conditions in controlled preclinical laboratory studies.

The 100 highest-cited original articles in large vessel occlusions: A bibliometric analysis.

BACKGROUND: Large vessel occlusions (LVO) are a common etiology of morbidity and mortality. The current literature lacks a synthesis of the landscape and trends in research. OBJECTIVE: We aimed to conduct a bibliometric analysis of the 100 most cited original articles on LVOs to assess the current state of research. METHODS: Scopus database was queried from inception to December 2022 to identify the most cited original articles from 4506 retrieved records on LVOs. Publication year, country of origin, total and average annual citation count, and type of study were collected for each article. The journal impact factor (JIF) was obtained from the Journal Citation Reports database. RESULTS: The articles were published between 1994 and 2021, with most (n = 82) published during the 2011-2020 decade. The median total citation count was 108.5, with an interquartile range (IQR) of 81-149.5. The median (IQR) average annual citation count was 15.9 (11.5-22.9). Half of the articles were published in Stroke (n = 35) and Journal of NeuroInterventional Surgery (n = 15), with JIFs ranging from 1.8 to 202.7. The USA was the leading country in contributing to LVO research (n = 45). Most studies focused on the treatment (n = 63) and diagnosis (n = 22) of LVOs. CONCLUSIONS: Most articles were published during the past decade, highlighting the impact of the clinical trials of endovascular treatment on the discipline. With several ongoing clinical trials on the horizon, continued growth of the field is anticipated in the upcoming decades.

ROTEM and von Willebrand Factor in COVID Patients Presenting with Acute Ischemic Stroke: A Case Series.

OBJECTIVES: SARS-CoV-2 (COVID) induces systemic thrombotic complications including acute ischemic stroke. In this case series, we report markers of inflammation, coagulation factors including von Willebrand factor antigen, and rotational thromboelastometry (ROTEM) data. MATERIALS AND METHODS: Retrospective case series of COVID patients seen at a single comprehensive stroke center between 2020 - 2022. For patients undergoing mechanical thrombectomy (MT), ROTEM data was collected during the procedure and analyzed on ROTEM delta system. RESULTS: Fifteen patients (33.3% female) median age 65-years-old presented with COVID and acute ischemic stroke. Thirteen had LVO. The mean NIHSS was 15 (range 0 - 35) on admission and 18 (0 - 42) at discharge. Most were cryptogenic (N=7, 46.7%), followed by cardioembolic (N=6, 40%) and large artery-to-artery embolization (N=2, 13.3%). mRS was < 3 in 8 (53%) patients at discharge. None of the patients were on anticoagulation, and five were on antiplatelet therapy pre-hospitalization. Seven received thrombolytics with alteplase (tPA), and 10 had MT. Baseline platelet count was 102 K/uL (range 102 - 291 K/uL). vWF was measured in 12 patients, all elevated, with seven having levels >400 (180%). ROTEM data was collected in six patients. Three who received tPA had abnormal EXTEM and FIBTEM data (CT extem > 85secs, A10 EXTEM < 45mm, and A10 FIBTEM < 10mm). Notably, INTEM (CT INTEM >208secs) was abnormal in five of the six patients, two of whom did not receive tPA. CONCLUSIONS: Elevated vWF antigen levels with abnormal ROTEM data suggests that COVID induces changes in the clotting cascade. More robust research is needed to investigate these findings. Thrombolytics, MT, and antiplatelet agents should be utilized to treat COVID-related ischemic stroke based on current clinical guidelines.

Ischemic stroke or transient ischemic attack due to cervical and intracranial large-vessel vasculitis secondary to primary Sjögren's syndrome: A case series and literature review.

Introduction: Primary Sjögren's syndrome (PSS) is a systemic autoimmune disease that mainly affects exocrine glands. Little is known about PSS associated cervical and intracranial cerebral large-vessel vasculitis outside of individual case reports. Methods: We present 5 cases of ischemic stroke or transient ischemic stroke (TIA) caused by PSS associated cervical and intracranial large-vessel vasculitis. Literature review was performed to summarize and identify the demographic, clinical features, treatment, and prognosis of this condition. Results: The review resulted in 8 included articles with 8 patients, plus our 5 new patients, leading to a total of 13 subjects included in the analysis. The median age was 43 (range, 17-69) years old, among which 69.2 % (9/13) were female, and 92.3 % (12/13) came from Asia. Among them, 84.6 % (11/13) presented with cerebral infarction and 70.0 % (7/10) with watershed infarction. Middle cerebral artery (MCA) (6/13, 46.2 %) and internal carotid artery (ICA) (6/13, 46.2 %) were the most frequently involved arteries. Remarkable vessel wall concentric thickening and enhancement was observed in 57.1 % (4/7) patients and intravascular thrombi was identified in 28.6 % (2/7) patients. Glucocorticoid combined with non-glucocorticoid immunosuppressants (8/12, 66.7 %) were the most often chosen medication therapy and 4 patients received surgical intervention. Conclusion: Asian females are the most vulnerable population to ischemic stroke or TIA due to PSS associated cervical and intracranial large-vessel vasculitis. Cerebral infarctions were characterized by recurrence and watershed pattern. Magnetic resonance vessel wall imaging (MR-VWI) helps to identify the inflammatory pathology of large vessel lesion in PSS.

Large vessel vasculitis is a risk factor for relapse only in giant cell arteritis patients without polymyalgia rheumatica.

OBJECTIVES: To evaluate differences in presentation and outcome of giant cell arteritis (GCA) patients with and without large vessel vasculitis (LVV) and according to the extent and severity of LVV. METHODS: Consecutive patients diagnosed with GCA between 2003 and 2020 who have had FDG PET imaging at diagnosis ≤3 days after initiation of glucocorticoids and followed for ≥12 months at the University Hospitals Leuven (Belgium), were included retrospectively. PET scans were visually scored (0-3) in 7 vascular areas and a total vascular score (TVS) was calculated. LVV was defined as FDG uptake ≥2 in any large vessel. RESULTS: We included 238 GCA patients, of which 169 (71%) had LVV. LVV patients were younger (69 vs 74 years, p< 0.001) and more frequently female (72% vs 49%, p= 0.001). In patients without PMR symptoms, the presence of LVV was associated with relapse (aOR 3.05 [95%CI 1.32-7.43], p= 0.011) and with a lower probability of stopping glucocorticoids (aHR 0.59 [95%CI 0.37-0.94], p= 0.025). However, in those with PMR symptoms, there was no difference in relapse risk (aOR 1.20 [95%CI 0.53-2.66], p= 0.657) and in the probability of stopping glucocorticoids (aHR 1.25 [95%CI 0.75-2.09], p= 0.394) between patients with and without LVV. A higher TVS was associated with an increased risk of relapse (aOR 1.09 [95%CI 1.04-1.15], p= 0.001] in patients without PMR symptoms, but not in those with PMR symptoms (aOR 1.01 [95%CI 0.96-1.07], p= 0.693). CONCLUSION: LVV is a risk factor for relapse in GCA patients without PMR symptoms with a higher relapse risk in those with higher TVS.

Intravenous thrombolysis versus dual antiplatelet therapy in minor ischemic stroke within the thrombolytic window (TAMIS): a multicenter cohort study.

Intravenous thrombolysis (IVT) and dual antiplatelet therapy (DAPT) have been widely used in minor ischemic stroke (MIS) treatment. However, the clinical outcomes and safety of these two treatments have not been compared within the early thrombolytic time window. Here, we conducted a multicenter, ambispective cohort study involving patients with MIS presenting within 4.5 h of symptom onset at 3 affiliated hospitals of Jinan University from 2018-2022. The patients were divided into the IVT group and DAPT group. The primary outcome was a 90-day excellent outcome (mRS ≤ 1). A total of 1,026 patients were enrolled, of whom 492 were assigned to the IVT group and 534 were assigned to the DAPT group. The IVT group had better 90-day excellent outcomes (mRS ≤ 1) than the DAPT group (OR 1.69, 95% CI 1.14-2.52, P = 0.010). Among the 623 patients with nondisabling stroke, the proportion of mRS ≤ 1 in the IVT group was higher than the DAPT group (P = 0.009). In the subtypes of MIS with large vessel occlusion/stenosis and with isolated symptoms, the 90-day outcomes of the IVT group and DAPT group were not different (P > 0.05). In conclusion, compared with DAPT, IVT was associated with better 90-day clinical outcomes in patients with MIS (in particular, for those with mRS > 1), including earlier clinical improvement.IVT also benefited the early neurological improvement of patients with severe stenosis/occlusion of intracranial large vessels, nondisabling mild stroke, nondisabling mild stroke with isolated symptoms.

Role and potential of 18F-fluorodeoxyglucose-positron emission tomography-computed tomography in large-vessel vasculitis: a comprehensive review.

Large-vessel vasculitis (LVV) is a group of diseases characterized by inflammation of the aorta and its main branches, which includes giant cell arteritis (GCA), polymyalgia rheumatica (PMR), and Takayasu's arteritis (TAK). These conditions pose significant diagnostic and management challenges due to their diverse clinical presentations and potential for serious complications. 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG-PET-CT) has emerged as a valuable imaging modality for the diagnosis and monitoring of LVV, offering insights into disease activity, extent, and response to treatment. 18F-FDG-PET-CT plays a crucial role in the diagnosis and management of LVV by allowing to visualize vessel involvement, assess disease activity, and guide treatment decisions. Studies have demonstrated the utility of 18F-FDG-PET-CT in distinguishing between LVV subtypes, evaluating disease distribution, and detecting extracranial involvement in patients with cranial GCA or PMR phenotypes. Additionally, 18F-FDG-PET-CT has shown promising utility in predicting clinical outcomes and assessing treatment response, based on the correlation between reductions in FDG uptake and improved disease control. Future research should focus on further refining PET-CT techniques, exploring their utility in monitoring treatment response, and investigating novel imaging modalities such as PET-MRI for enhanced diagnostic accuracy in LVV. Overall, 18F-FDG-PET-CT represents a valuable tool in the multidisciplinary management of LVV, facilitating timely diagnosis and personalized treatment strategies to improve patient outcomes.

Evaluation of partial resheathing of EmboTrap III using the microcatheter (PREMIER) technique for fibrin-rich hard clots in an in vitro vessel model.

Background and purpose: Despite the ongoing advancements in mechanical thrombectomy for large vessel occlusions causing acute ischemic stroke, successful recanalization is not achieved in all patients. One contributing factor is the presence of fibrin-rich hard clots. We proposed a new technique called the PREMIER technique, which aims to retrieve fibrin-rich clots. This study evaluated the efficacy of the PREMIER technique on fibrin-rich and erythrocyte-rich clots by comparing it with the simple use of EmboTrap III in an in vitro vessel model. Methods: The PREMIER technique involves partially resheathing a fully deployed EmboTrap III (CERENOVUS, Johnson & Johnson Medical Devices, Irvine, California, USA) using a microcatheter to capture and retrieve a hard clot between the inner channel and outer cages of EmboTrap III. We compared recanalization rate of the PREMIER technique with the simple use of EmboTrap III in an in vitro vessel model, occluding the M1 segment with fibrin-rich hard clots (0% erythrocyte composition) and erythrocyte-rich clots (50% erythrocyte composition). Results: Among the 40 procedures (10 each for the PREMIER technique and the simple use of EmboTrap III for two different clots) for fibrin-rich clots, the PREMIER technique achieved successful recanalization in all 10 cases, with a significantly higher recanalization rate than the EmboTrap III (100% vs. 50%, p = 0.03). For erythrocyte-rich clots, the recanalization rate was not significantly different in the PREMIER technique compared with the simple use of EmboTrap III (80% vs. 70%, p = 1.00). Conclusion: The PREMIER technique is a novel technique for acute large-vessel occlusions caused by fibrin-rich hard clots that hinders successful recanalization during mechanical thrombectomy.

Automated identification of thrombectomy amenable vessel occlusion on computed tomography angiography using deep learning.

Introduction: We developed and externally validated a fully automated algorithm using deep learning to detect large vessel occlusion (LVO) in computed tomography angiography (CTA). Method: A total of 2,045 patients with acute ischemic stroke who underwent CTA were included in the development of our model. We validated the algorithm using two separate external datasets: one with 64 patients (external 1) and another with 313 patients (external 2), with ischemic stroke. In the context of current clinical practice, thrombectomy amenable vessel occlusion (TAVO) was defined as an occlusion in the intracranial internal carotid artery (ICA), or in the M1 or M2 segment of the middle cerebral artery (MCA). We employed the U-Net for vessel segmentation on the maximum intensity projection images, followed by the application of the EfficientNetV2 to predict TAVO. The algorithm's diagnostic performance was evaluated by calculating the area under the receiver operating characteristics curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: The mean age in the training and validation dataset was 68.7 ± 12.6; 56.3% of participants were men, and 18.0% had TAVO. The algorithm achieved AUC of 0.950 (95% CI, 0.915-0.971) in the internal test. For the external datasets 1 and 2, the AUCs were 0.970 (0.897-0.997) and 0.971 (0.924-0.990), respectively. With a fixed sensitivity of 0.900, the specificities and PPVs for the internal test, external test 1, and external test 2 were 0.891, 0.796, and 0.930, and 0.665, 0.583, and 0.667, respectively. The algorithm demonstrated a sensitivity and specificity of approximately 0.95 in both internal and external datasets, specifically for cases involving intracranial ICA or M1-MCA occlusion. However, the diagnostic performance was somewhat reduced for isolated M2-MCA occlusion; the AUC for the internal and combined external datasets were 0.903 (0.812-0.944) and 0.916 (0.816-0.963), respectively. Conclusion: We developed and externally validated a fully automated algorithm that identifies TAVO. Further research is needed to evaluate its effectiveness in real-world clinical settings. This validated algorithm has the potential to assist early-career physicians, thereby streamlining the treatment process for patients who can benefit from endovascular treatment.

Accuracy of FAST-ED for Assessment Large Vessel Occlusion of Acute Ischemic Stroke in Emergency Department.

Background: Acute large vessel occlusion stroke (LVOS) requires swift and precise assessment for effective treatment. The Field Assessment Stroke Triage for Emergency Destination (FAST-ED) protocol shows promise for rapid LVOS evaluation but lacks extensive validation. This study aims to assess the accuracy of FAST-ED in predicting LVOS and compare its predictive capability with the National Institute of Health Stroke Scale (NIHSS). Methods: This prospective cross-sectional study was conducted at Thammasat University Hospital. Participants included those aged 18 years or older who presented with symptoms of acute stroke syndrome within 24 hours of onset. The study focused on comparing FAST-ED assessments by emergency department physicians with NIHSS evaluations by neurologists, followed by vascular imaging, which included brain multiphase CT angiography, MRI with MRA, and transcranial Doppler ultrasound combined with carotid Doppler ultrasound. Statistical analyses included the use of AuROC to assess the effectiveness of FAST-ED and to compare FAST-ED with NIHSS. Results: 130 patients were included in the analysis, with 47 diagnosed with LVOS. No significant differences were found in most baseline characteristics between LVOS and non-LVOS groups, except for a higher prevalence of atrial fibrillation and lower systolic blood pressure in the LVOS group. The FAST-ED scale demonstrated a fair ability to predict LVOS with an AuROC of 0.79 (95% confidence interval (CI); 0.70, 0.87). A FAST-ED cut point of ≥4 showed improved specificity and likelihood ratio. Comparing FAST-ED≥4 with NIHSS≥6 revealed similar AuROC (0.74, 95% CI; 0.65, 0.82 and 0.72, 95% CI; 0.64, 0.80, respectively), with no significant statistical difference (p=0.661). Conclusion: FAST-ED scale, especially with a cut-off point of ≥4, exhibits fair overall accuracy in predicting LVOS in patients who presented with suspected acute stroke within 24 hours at the ED. This predictive capability is closely comparable to that of the NIHSS at a cut-off point of ≥6.

Relative Cerebral Blood Flow as an Indirect Imaging Surrogate in Patients With Anterior Circulation Large Vessel Occlusion and Association of Baseline Characteristics With Poor Collateral Status.

BACKGROUND: In acute ischemic stroke (AIS), collateral status (CS) is an important predictor of favorable outcomes in patients with AIS. Among quantitative cerebral perfusion parameters, relative cerebral blood flow (rCBF) is considered an accurate perfusion-based indicator of CS. This study investigated the relationship between admission laboratory values, baseline characteristics, and CS as assessed by rCBF in patients with AIS-large vessel occlusion. METHODS AND RESULTS: In this retrospective multicenter study, consecutive patients presenting with AIS secondary to anterior circulation large vessel occlusion who underwent pretreatment computed tomography perfusion were included. The computed tomography perfusion data processed by RAPID (IschemaView, Menlo Park, CA) generated the rCBF. Binary logistic regression models assessed the relationship between patients' baseline characteristics, admission laboratory values, and poor CS. The primary outcome measure was the presence of poor CS, which was defined as rCBF <38% at a lesion size ≥27 mL. Between January 2017 and September 2022, there were 221 consecutive patients with AIS-large vessel occlusion included in our study (mean age 67.0±15.8 years, 119 men [53.8%]). Logistic regression showed that male sex (odds ratio [OR], 2.98 [1.59-5.59]; P=0.001), chronic kidney disease (OR, 5.18 [2.44-11.0]; P<0.001), admission National Institutes of Health Stroke Scale score ≥12 (OR, 5.17 [2.36-11.36]; P<0.001), and systolic blood pressure <140 (OR, 2.00 [1.07-3.76]; P=0.030) were associated with poor CS. CONCLUSIONS: Higher stroke severity on admission with National Institutes of Health Stroke Scale score ≥12, systolic blood pressure <140, chronic kidney disease, and male sex are statistically significantly associated with poor CS in patients with AIS due to anterior circulation large vessel occlusion as defined by rCBF <38%.