Acute Posterior Circulation Stroke Research Articles

Differential efficacy of remote ischaemic conditioning in anterior versus posterior circulation stroke: A prespecified secondary analysis of the RICAMIS trial.

The benefit of remote ischaemic conditioning (RIC) in acute moderate ischaemic stroke has been demonstrated by the Remote Ischaemic Conditioning for Acute Moderate Ischaemic Stroke (RICAMIS) study. This prespecified exploratory analysis aimed to determine whether there was a difference of RIC efficacy in anterior versus posterior circulation stroke based on RICAMIS data. In this analysis, eligible patients presenting within 48 h of stroke onset were divided into two groups: anterior circulation stroke (ACS) and posterior circulation stroke (PCS) groups. The primary endpoint was an excellent functional outcome, defined as a modified Rankin Scale (mRS) score 0-1 at 90 days. In all, 1013 patients were included in the final analysis, including 642 with ACS and 371 with PCS. Compared with the control group, RIC was significantly associated with an increased proportion of mRS scores 0-1 within 90 days in the PCS group (unadjusted odds ratio 1.6, 95% confidence interval 1.0-2.4, p = 0.04; adjusted odds ratio 2.0, 95% confidence interval 1.2-3.3, p = 0.005), but not in the ACS group (p = 0.29). Similar results were found regarding secondary outcomes including mRS score 0-2 at 90 days, mRS distribution at 90 days and change in National Institutes of Health Stroke Scale score at day 12 from baseline. However, there was no significant interaction effect between stroke location and intervention on the primary outcome (pinteraction = 0.21). Amongst patients with acute PCS who are not candidates for reperfusion treatment, RIC may be associated with a higher probability of improved functional outcomes. These findings need to be validated in prospective trials.

Endovascular treatment effect in vertebrobasilar artery occlusion patients with posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS)

BackgroundEndovascular treatment (EVT) has revolutionized the standard treatment of vertebrobasilar artery occlusion (VBAO) with moderate infarct core, but its effectiveness in patients with a low posterior circulation Acute Stroke Prognosis...

Nomogram to predict prognosis in patients with posterior circulation acute ischemic stroke after mechanical thrombectomy.

This study aimed to investigate the risk factors of prognosis and hemorrhagic transformation after mechanical thrombectomy (MT) in patients with posterior circulation acute ischemic stroke (PC-AIS) caused by large vessel occlusion. We sought to develop a nomogram for predicting the risk of poor prognosis and symptomatic intracerebral hemorrhage (sICH) in patients with PC-AIS. A retrospective analysis was conducted on 81 patients with PC-AIS who underwent MT treatment. We collected clinical information from the patients to assessed sICH and prognosis based on CT results and National Institutes of Health Stroke Scale (NIHSS) scores. Subsequently, they were followed up for 3 months, and their prognosis was assessed using the Modified Rankin Scale. We used the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression to determine the factors affecting prognosis to construct a nomogram. The nomogram's performance was assessed through receiver operating characteristic curves, calibration curves, decision curve analysis, and clinical impact curves. Among the 81 patients with PC-AIS, 33 had a good prognosis, 48 had a poor prognosis, 19 presented with sICH, and 62 did not present with sICH. The results of the LASSO regression indicated that variables, including HPT, baseline NIHSS score, peak SBP, SBP CV, SBP SD, peak SBP, DBP CV, HbA1c, and BG SD, were predictors of patient prognosis. Variables such as AF, peak SBP, and peak DBP predicted the risk of sICH. Multivariate logistic regression revealed that baseline NIHSS score (OR = 1.115, 95% CI 1.002-1.184), peak SBP (OR = 1.060, 95% CI 1.012-1.111), SBP CV (OR = 1.296, 95% CI 1.036-1.621) and HbA1c (OR = 3.139, 95% CI 1.491-6.609) were independent risk factors for prognosis. AF (OR = 6.823, 95% CI 1.606-28.993), peak SBP (OR = 1.058, 95% CI 1.013-1.105), and peak DBP (OR = 1.160, 95% CI 1.036-1.298) were associated with the risk of sICH. In the following step, nomograms were developed, demonstrating good discrimination, calibration, and clinical applicability. We constructed nomograms to predict poor prognosis and risk of sICH in patients with PC-AIS undergoing MT. The model exhibited good discrimination, calibration, and clinical applicability.

Computed tomography perfusion deficit volume predicts the functional outcome of endovascular therapy for basilar artery occlusion

ObjectivesTo investigate the relationship between baseline computed tomography perfusion deficit volumes and functional outcomes in patients with basilar artery occlusion (BAO) undergoing endovascular therapy. MethodsThis was a single-center study in which the data of 64 patients with BAO who underwent endovascular therapy were retrospectively analyzed. All the patients underwent multi-model computed tomography on admission. The posterior-circulation Acute Stroke Prognosis Early Computed Tomography Score was applied to assess the ischemic changes. Perfusion deficit volumes were obtained using Syngo.via software. The primary outcome of the analysis was a good functional outcome (90-day modified Rankin Scale score ≤ 3). Logistic regression and receiver operating characteristic curves were used to explore predictors of functional outcome. ResultsA total of 64 patients (median age, 68 years; 72 % male) were recruited, of whom 26 (41 %) patients achieved good functional outcomes, while 38 (59 %) had poor functional outcomes. Tmax > 10 s, Tmax > 6 s, and rCBF < 30 % volume were independent predictors of good functional outcomes (odds ratio range, 1.0–1.2; 95 % confidence interval [CI], 1.0–1.4]) and performed well in the receiver operating characteristic curve analyses, exhibiting positive prognostic value; the areas under the curve values were 0.85 (95 % CI, 0.75–0.94), 0.81 (95 % CI, 0.70–0.90), and 0.78 (95 % CI, 0.67–0.89). ConclusionComputed tomography perfusion deficit volume represents a valuable tool in predicting high risk of disability and mortality in patients with BAO after endovascular treatment.

Effect of anesthesia mode during endovascular treatment on neurological functional outcomes in patients with acute posterior circulation stroke.

To compare the effect of anesthesia mode on the neurological functional outcomes in patients undergoing endovascular treatment for acute posterior circulation ischemic stroke. Clinical data of 656 patients undergoing intravascular therapy for acute posterior circulation ischemic stroke registered in online Acute Stroke Patients for Stroke Management Quality Evaluation Database from January 2017 to December 2022 were retrospectively analyzed. The data included 163 cases with conscious sedation and 493 cases with general anesthesia during the procedure. After propensity score matching, 428 patients were included in the analysis, including 155 cases in the conscious sedation group and 273 cases in the general anesthesia group. The differences of operation mode, etiology type, vascular recanalization, hemorrhagic transformation at 24 h, modified Rankin Scale (mRS) score at 3 months and mortality within 3 months were compared between the two groups. Binary logistic regression was used to explore the effect of different anesthesia mode on neurological functional outcomes. There was a significant difference in operation mode between the two groups (P<0.01), while there were no significant differences in etiology type, vascular recanalization, hemorrhagic transformation at 24 h, mRS score at 3 months or mortality within 3 months (all P>0.05). Binary logistic regression analysis revealed that anesthesia modes were not significantly associated with functional outcomes of patients (OR=1.151, 95%CI: 0.751-1.765, P>0.05). Anesthesia mode (conscious sedation or general anesthesia) will not affect the neurological functional outcomes in patients with acute posterior circulation ischemic stroke undergoing endovascular treatment.

First pass effect in patients undergoing endovascular treatment for posterior circulation acute ischemic stroke

ObjectiveThis study aims to investigate the impact of first pass effect (FPE) on outcomes in the posterior circulation acute ischemic stroke (PC-AIS) and the independent predictors of FPE. MethodsThis was a multicenter, retrospective study. PC-AIS patients who underwent endovascular treatment were reviewed. The cohort achieving complete or nearly complete reperfusion (defined as expanded treatment in cerebralischemia [eTICI] ≥ 2c) was categorized into the FPE and multiple pass effect (MPE) groups. FPE was defined as achieving eTICI ≥ 2c with a single pass and without the use of rescue therapy. Modified FPE (mFPE) was defined as meeting the criteria for FPE but with eTICI ≥ 2b. The association of FPE with 90-day clinical outcomes and predictors for FPE were both investigated. ResultsThe study included a total of 328 patients, with 69 patients (21 %) in the FPE group. For primary outcome, FPE had a significant higher favorable outcome (mRS ≤ 3) rate than MPE (65.2 % vs. 44.8 %, p = 0.003). Similar outcomes were observed in the mFPE. Furthermore, FPE was significantly associated with favorable outcome (adjusted OR 2.23, 95 % CI 1.06-4.73, p = 0.036). Positive predictors for FPE included occlusion in the distal basilar artery, the first-line aspiration or combination, and cardioembolic etiology. Negative predictors for FPE included hypertension and general anesthesia. ConclusionFor PC-AIS patients due to large or medium vessel occlusion, FPE is associated with favorable clinical outcomes. The first-line techniques of aspiration or combination, as well as avoiding general anesthesia, contribute to a better realization of FPE.

Efficacy of Endovascular Thrombectomy in Acute Basilar Artery Occlusion with Low PC-ASPECTS: A Nationwide Prospective Registry-Based Study.

We evaluated the efficacy of endovascular thrombectomy (EVT) on the functional outcome of patients with acute basilar artery occlusion and low posterior circulation acute stroke prognosis early computed tomography score (PC-ASPECTS). We identified patients with acute ischemic stroke due to basilar artery occlusion and PC-ASPECTS of 6 or less, presenting within 24 h between August 2008 and April 2022. The primary outcome was a favorable functional outcome, defined as a modified Rankin Scale (mRS) score of 0-3 at 90 days. The secondary outcomes included an mRS score of 0-2, a favorable shift in the ordinal mRS scale, the occurrence of symptomatic intracranial hemorrhage (sICH), and mortality at 90 days. We compared the outcome of patients treated with EVT and those without EVT, using the inverse probability of treatment weighting methods. Out of 566 patients, 55.5% received EVT. In the EVT group, 106 (33.8%) achieved favorable outcomes, compared to 56 patients (22.2%) in the conservative group. EVT significantly increased the likelihood of achieving a favorable outcome compared to conservative treatment (relative risk [RR] 1.39, 95% confidence interval [CI], 1.11-1.74, p = 0.004). EVT was associated with a favorable shift in the mRS (RR 1.85, 95% CI, 1.49-2.29, p < 0.001) and reduced mortality without an increase in the risk of sICH. It did not have an impact on achieving an mRS score of 0-2. Patients with acute basilar artery occlusion and a PC-ASPECTS of 6 or less might benefit from EVT without an increasing sICH. ANN NEUROL 2024;95:788-799.

Abstract TP132: Optimal CT Perfusion Post-Processing Method in Posterior Circulation Stroke

Objective: CT-perfusion (CTP) has revolutionised stroke care by improving diagnostic accuracy and expanding eligibility to acute therapies. Software packages utilise various mathematical techniques to transform raw perfusion data into measures of infarct core and ischaemic penumbra. These techniques have been derived from studies of anterior-circulation stroke and not yet validated in posterior circulation stroke (PCS). We examined the optimal CTP thresholds for acute PCS. Methods: Data were analysed from 331-patients diagnosed with a PCS enrolled in the International-stroke-perfusion-registry (INSPIRE). Twenty-seven-patients with baseline multimodal-CT with occlusion of a large posterior-circulation (PC) artery and follow up diffusion-weighted-MRI at 24-48 hours were included. CTP parametric maps were generated using five different post-processing methods. Receiver-operating-curve analysis was used to determine the optimal perfusion parameter and thresholds. Results: Partial deconvolution was the optimal post-processing method for characterisation of ischaemic penumbra and infarct core. Mean transit time (MTT) at a threshold of &gt;165% and &gt;195% most accurately defined ischaemic core (AUC=0.73) and penumbra (AUC=0.78) respectively. Post-processing technique influenced accuracy of core (AUC range=0.54-0.73) and penumbra (AUC range=0.72-0.79) estimates. MTT was consistently the most accurate parameter at distinguishing core and penumbra across all post-processing methods. Conclusion: CTP has significant diagnostic utility in PCS. Accuracy of CTP varies considerably by post-processing method. The underlying post-processing technique employed by individual software packages should be considered when interpreting the accuracy of ischemic core and penumbra estimates.

General anesthesia vs. conscious sedation and local anesthesia for endovascular treatment in patients with posterior circulation acute ischemic stroke: An updated systematic review and meta-analysis

IntroductionThe best anesthetic choice for patients with acute posterior circulation stroke during endovascular treatment (EVT) remains uncertain. MethodWe searched five databases to identify studies that met the inclusion criteria. Our primary outcome measure was functional independence (FI). Secondary outcomes were 3-month mortality, any intracranial hemorrhage (ICH), symptomatic ICH (sICH), successful reperfusion, and procedure- and ventilator-associated complications. ResultsA total of 10 studies were included in our meta-analysis. No significant differences were detected between the general anesthesia (GA) and conscious sedation and local anesthesia (CS/LA) groups in 3-month FI (nine studies; OR=0.69; 95% CI 0.45–1.06; P=0.083; I2=66%;), 3-month mortality (nine studies; OR=1.41; 95% CI 0.94–2.11; P=0.096; I2=61.2%;), any ICH (three studies; OR=0.75; 95% CI 0.44–1.25; P=0.269; I2=0%;), or sICH (six studies; OR=0.64; 95% CI 0.40–1.04; P=0.073; I2=0%;). No significant differences were observed for successful reperfusion (10 studies; OR=1.17; 95% CI 0.91–1.49; P=0.219; I2=0%;), procedure-related complications (four studies; OR=1.14; 95% CI 0.70–1.87; P=0.603; I2=7.9%;), or respiratory complications (four studies; OR=1.19; 95% CI 0.61–2.32; P=0.616; I2=64.9%;) between the two groups. ConclusionsOur study showed no differences in 3-month FI, 3-month mortality, and successful reperfusion between patients treated with GA and those treated with CS/LA. Additionally, no increased risk of hemorrhagic transformation or pulmonary infection was observed in the CS/LA group. These results indicate that CS/LA may be an EVT option for acute posterior circulation stroke patients.

The value of computed tomography perfusion deficit volumes in acute isolated brainstem infarction.

Diagnosis of acute isolated brainstem infarction is challenging owing to non-specific, variable symptoms, and the effectiveness of non-contrast computed tomography (NCCT) is poor owing to limited spatial resolution and artifacts. Computed tomography perfusion (CTP) imaging parameters are significantly associated with functional outcomes in posterior circulation acute ischemic stroke; however, the role of CTP in isolated brainstem infarction remains unclear. We aimed to determine the value of CTP imaging parameters in predicting functional outcomes for affected patients. In total, 116 consecutive patients with isolated pontine/midbrain hypoperfusion who underwent CTP and follow-up by magnetic resonance imaging (MRI) between January 2018 and March 2022, were retrospectively analyzed. Perfusion deficit volumes on all maps, and the final infarction volume (FIV) on MRI were quantified. "Good" functional outcome was defined as a 90-day modified Rankin Scale score of 0 and 1. Statistical analysis included uni- and multivariate regression analyses, binary logistic regressions, and receiver operating characteristics (ROC) analyses. In total, 113 patients had confirmed isolated pontine/midbrain infarction on follow-up MRI. Onset-to-scan time, visibility of ischemic lesions on NCCT, the baseline National Institutes of Health Stroke Scale (NIHSS) score, and perfusion deficit volumes on all CTP maps were significantly associated with FIV (p < 0.05). In a multivariate linear regression model, adjusted for age, sex, NIHSS score, onset-to-scan time, and visibility of NCCT, perfusion deficit volumes remained significantly associated with FIV. In binary logistic regression analyses, perfusion deficit volumes on all CTP maps remained independent predictors of a good functional outcome. In ROC analyses, the cerebral blood flow deficit volume showed a slightly higher discriminatory value with the largest area under the curve being 0.683 [(95% CI, 0.587-0.780), p = 0.001]. Perfusion deficit volumes of CTP imaging could reflect the FIV and contain prognostic information on functional outcomes in patients with acute isolated brainstem infarction.

Prognostic value of the baseline magnetic resonance score in patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy

To investigate the prognostic value of the composite posterior circulation Acute Stroke Prognosis Early Computed tomography (CT) Score (ASPECTS)-Collaterals (pcASCO) score, which combines diffusion-weighted imaging (DWI) posterior circulation ASPECTS (pcASPECTS) and the magnetic resonance angiography (MRA)-collateral circulation score at baseline among patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy. Patients with acute posterior circulation ischaemic stroke who underwent mechanical thrombectomy were analysed retrospectively. The DWI-pcASPECTS and MRA-collateral circulation score before treatment and the modified Rankin Scale (mRS) at 90 days after treatment were used as the endpoints. An mRS ≤2 was defined as a good prognosis, and an mRS ≥3 was defined as a poor prognosis. Multivariate logistic regression was used to analyse independent predictors of functional outcome 90 days after mechanical thrombectomy. Mechanical thrombectomy was performed in 57 patients; 38 patients had a good prognosis, 19 patients had a poor prognosis, and 33 patients were successfully recanalised. Univariate logistic regression found that National Institute of Health Stroke Scale (NIHSS) score (OR: 1.18, p<0.001), pcASPECTS (OR: 1.91, p=0.028) and pcASCO score (OR: 0.51, p=0.001) were factors of good functional outcome. Receiver operating characteristic curve (ROC curve) analysis showed that the diagnostic efficiency of the NIHSS and pcASCO was better (AUC=0.88, 0.83, p<0.05) than that of the pcASPECTS (AUC=0.65). The prediction model was established by age, NIHSS, and pcASCO, and the diagnostic efficiency of the prediction model was better (AUC=0.94). The composite MR-pcASCO score can be used as an important predictor of the prognosis of patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy.

Outcomes of Endovascular Treatment versus Standard Medical Treatment for Acute Ischemic Stroke with Basilar Artery Occlusion: A Systematic Review and Meta-Analysis.

Although endovascular treatment (EVT) is beneficial for large vessel occlusion in anterior circulation stroke, whether these benefits exist for basilar artery occlusion (BAO) remains unclear. This systematic review and meta-analysis compared the outcomes of patients with BAO undergoing EVT and standard medical treatment (SMT). The PubMed, Embase, and Cochrane Library databases were searched for eligible randomized control trials (RCTs) and non-RCTs involving patients with acute ischemic stroke and BAO undergoing EVT or SMT. The following outcomes were assessed: 90-day functional outcomes (favorable outcome and functional independence: modified Rankin scale [mRS] score of 0-3 or 0-2, respectively), mortality, and symptomatic intracranial hemorrhage (sICH) incidence. The summary effect sizes were determined as risk ratios (RRs) through the Mantel-Haenszel method with a random-effects model. Four RCTs and four non-RCTs were included. Compared with SMT, EVT resulted in a higher proportion of patients with 90-day mRS scores of 0-3 (RR: 1.54 [1.16-2.06] in RCTs and 1.88 [1.11-3.19] in non-RCTs), a higher proportion of patients achieving functional independence (90-day mRS score of 0-2; RR: 1.83 [1.07-3.12] and 1.84 [0.97-3.48], respectively), a lower risk of mortality (RR: 0.76 [0.65-0.89] and 0.72 [0.62-0.83], respectively), and a higher sICH risk (RR: 5.98 [2.11-16.97] and 4.95 [2.40-10.23], respectively). Severe neurological deficits, intravenous thrombolysis, and higher posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) were associated with EVT benefits. In patients with BAO, EVT results in superior functional outcomes, lower mortality risk, and higher sICH risk than does SMT, independent of age and sex. Higher National Institutes of Health Stroke Scale scores, intravenous thrombolysis, and higher pc-ASPECTSs before treatment are associated with greater benefits from EVT.

Prospective analysis of video head impulse tests in patients with acute posterior circulation stroke.

Video head impulse tests (vHITs), assessing the vestibulo-ocular reflex (VOR), may be helpful in the differential diagnosis of acute dizziness. We aimed to investigate vHITs in patients with acute posterior circulation stroke (PCS) to examine whether these findings could exhibit significant abnormalities based on lesion locations, and to evaluate diagnostic value of vHIT in differentiating dizziness between PCS and vestibular neuritis (VN). We prospectively recruited consecutive 80 patients with acute PCS and analyzed vHIT findings according to the presence of dorsal brainstem stroke (DBS). We also compared vHIT findings between PCS patients with dizziness and a previously studied VN group (n = 29). Receiver operating characteristic (ROC) analysis was performed to assess the performance of VOR gain and its asymmetry in distinguishing dizziness between PCS and VN. Patients with PCS underwent vHIT within a median of 2 days from stroke onset. Mean horizontal VOR gain was 0.97, and there was no significant difference between PCS patients with DBS (n = 15) and without (n = 65). None exhibited pathologic overt corrective saccades. When comparing the PCS group with dizziness (n = 40) to the VN group (n = 29), patients with VN demonstrated significantly lower mean VOR gains in the ipsilesional horizontal canals (1.00 vs. 0.57, p < 0.001). VOR gain and their asymmetry effectively differentiated dizziness in the PCS from VN groups, with an area under the ROC curve of 0.86 (95% CI 0.74-0.98) and 0.91 (95% CI 0.83-0.99, p < 0.001), respectively. Significantly abnormal vHIT results were rare in patients with acute PCS, even in the presence of DBS. Moreover, vHIT effectively differentiated dizziness between PCS and VN, highlighting its potential for aiding differential diagnosis of acute dizziness.

Acute left vertebral artery dissection and right vertebral artery occlusion in a middle-aged man: A case report

Spontaneous left Vertebral Artery Dissection (VAD) is an uncommon but very important etiology of acute posterior circulation stroke. We reported a case of a 43 years old man, who came with the complaint of chest pain with sudden onset, severe sweating

Pre-treatment risk markers for hemorrhagic transformation in posterior circulation acute ischemic stroke treated with reperfusion therapy.

Hemorrhagic transformation (HT) is an uncommon complication of posterior circulation acute ischemic stroke (PCS) compared to anterior circulation stroke. Nevertheless, it remains a major concern especially following reperfusion therapy. This study aimed at identifying potential predictive factors associated with HT in PCS. Consecutive patients, from a multicenter cohort, with PCS treated by IVT or EVT or the combination of both, were included from December 2015 to May 2019. The European Cooperative Acute Stroke Study criteria was used to identify HT. Potential risk factors were analyzed using univariate and multivariable testing models. A total of 96 patients were included in our study. Median age was 66 (57-83) years, 54 patients (56%) were male and median baseline NIHSS was 8 (4-14). 77 patients (80%) received IVT and 54 patients (56%) benefited from EVT. HT occurred in 19 patients (20%), while sHT occurred in 3 patients (3%). HT was found to be associated with poor functional status at 3months in univariate analysis (p = 0.0084). Multivariable analysis confirmed that higher baseline NIHSS (OR 1.1008; 95% CI [1.0216-1.1862]; p = 0.0117) and lobar topography of ischemia (OR 4.4275; 95% CI [1.3732-14.2753]; p = 0.0127) were independent predictors of the occurrence of HT. HT is associated with increased morbidity in patients with PCS; higher NIHSS and lobar ischemia were independent predictors of HT in our population. Easy-to-use predictive markers may help to tailor therapeutic management of patients with PCS.

Study on posterior circulatory stroke characteristics and clinico-radiological imaging

Background: Stroke research and clinical trials have focused mainly on anterior circulation stroke (ACS). Since clinical characteristics, mechanisms, and risk factors of posterior circulation stroke (PCS) have been reported different from ACS, more PCS studies are required. Methods: A Prospective, observational, Clinical study. All patients presenting to the department of general medicine and neurology of saveetha medical college from august 2021 to January 2023 with new onset neuro-deficit. Inclusion criteria is patients age 18 years or older and Clinical profile, radiological finding which is suggestive of acute PCS. Radiological imaging was done in detail to assess the artery involved and area affected. Results: Most common associated risk factors were hypertension (61%), alcoholism (33%) and smoking (32%). Most common presenting clinical symptoms of cases with PCS are giddiness (59%), left/ right sided weakness (48%). Posterior cerebral artery was involved in 45% of the patients. The next common involvement was that of the posterior inferior cerebellar artery (38%). Most common area involved was brainstem, cerebellum. Conclusions: This study describes the pattern of risk factors and clinical characteristics of PCS. Males were affected more than females. Age group commonly involved was above sixty years. Hypertension, alcoholism, diabetes and smoking contributed the major risk factors. Giddiness was commonest symptom at the onset. Most of the patients had clinical signs of cerebellum and brainstem lesions. The territory commonly involved was mid-brain, cerebellum, thalamus, occipital and temporal lobes.

Vertebrobasilar artery cooling infusion in acute ischemic stroke for posterior circulation following thrombectomy: Rationale, design and protocol for a prospective randomized controlled trial.

Although endovascular mechanical thrombectomy demonstrates clinical efficacy in posterior circulation acute ischemic stroke (AIS), only one third of these patients attain functional independence with a third of patients' expiring despite vascular recanalization. Neuroprotection strategies, such as therapeutic hypothermia (TH) have been considered a promising adjunctive treatment in AIS. We propose the following rationale, design and protocol for a prospective randomized controlled trial (RCT) aimed to determine whether Vertebrobasilar Artery Cooling Infusion (VACI) improves functional outcomes in posterior circulation AIS patients post mechanical thrombectomy. Subjects in the study will be assigned randomly to either the cooling infusion or the control group in a 1:1 ratio (n = 40). Patients allocated to the cooling infusion group will receive 300 ml cool saline at 4C through the catheter (30 ml/min) into vertebral artery after thrombectomy. The control group will receive the same volume of 37C saline. All patients enrolled will receive standard care according to current guidelines for stroke management. The primary outcome is symptomatic intracranial hemorrhage (ICH), whereas the secondary outcomes include functional outcome score, infarction volume, mortality, ICH, fatal ICH, cerebral vasospasm, coagulation abnormality, pneumonia and urinary infection. This study will determine the preliminary safety, feasibility, and neuroprotective benefits of VACI in posterior circulation AIS patients with reperfusion therapy. The results of this study may provide evidence for VACI as a new therapy in posterior circulation AIS. www.chictr.org.cn, ChiCTR2200065806, registered on November 15, 2022.

Case report - sulfonylurea poisoning mimicking vertebrobasilar acute ischemic stroke

Background: We report the case of sulfonylurea induced hypoglycemia manifesting as acute encephalopathy with focal neurological signs misdiagnosed as posterior circulation acute ischemic stroke (AIS) and discuss the potential effects of hypoglycemia on central nervous system, as well as its differentiation from AIS. Case presentation: A 64-year-old patient with type II diabetes treated with glimepiride was transferred to the Department of Neurology after the procedure of radical prostatectomy. On admission, the patient was unconscious with four limb paresis and bilateral Babinski sign. Non-contrast head CT and CT angiography vessels did not reveal any abnormalities. Due to exceeded therapeutic window the patient was disqualified from intravenous thrombolysis. At the admission hypoglycemia was observed and promptly corrected with the 5% dextrose infusion. For the next 72 hours repeated intravenous glucose infusions were needed to maintain its levels above 70 mg/dl. Based on the absence of ischemic changes on MRI and repeated decreases in glucose level for the next 3 days, glimepiride induced hypoglycemic encephalopathy was diagnosed. Within 24 hours of admission the patient regained consciousness and eventually presented four-limb paresis as a result of prolonged neuroglycopenia. Conclusions: Prolonged insufficient brain nutrition can result in permanent or long-lasting brain damage, manifesting as impaired consciousness and focal neurological signs. Perioperative sulfonylureas intake may result in prolonged hypoglycemia.

Abstract Number ‐ 183: pcASPECTS can help predict clinical outcome in basilar artery occlusion strokes who undergo endovascular thrombectomy

Introduction Basilar artery occlusion (BAO) is a life‐threatening condition associated with high morbidity and mortality. The clinical effectiveness of endovascular therapy (EVT) in patients with stroke due to BAO is not well established. The objective of our study is to investigate the role of Posterior circulation Acute Stroke Prognosis Early CT Score (pcASPECTS) in predicting clinical outcome in patients with BAO who undergo EVT. Methods We conducted a retrospective analysis on 45 patients with acute BAO who received EVT from November 2015 to June 2022. Information was collected on demographic variables, medical history, clinical parameters, and CT based pcASPECTS on admission. Functional outcomes were assessed via binarization of the following variables: the modified Rankin scale score on discharge, NIH stroke scale on discharge, and the modified Rankin scale score 90 days following discharge. A series of logistic regression models adjusted for age, gender, atrial fibrillation, systolic blood pressure at admission, tPA receipt, and NIH stroke scale on admission were run to assess the association of pcASPECTS score on admission with binarized outcome measures. Results Among 45 patients (mean age 63.6+11.4 years, 73.3% males), binarized pcASPECTS score on admission (&lt; 7: greater severity, &gt;7: lower severity) was not shown to be significantly associated with functional outcome across a series of logistic regression models. When assessing for binarized modified Rankin scale at discharge (0‐3: good outcome, 4–6: poor outcome), a lower severity of pcASPECTS showed 5.47 times the odds of a good outcome (OR: 5.47; 95% CI: 0.17, 173.25; p‐value: 0.34). When assessing for binarized NIH stroke scale on discharge (0‐15: mild/moderate; &gt;15: severe), a lower severity pcASPECTS showed 6.05 times the odds of a mild/moderate outcome as opposed to a severe outcome (OR: 6.05; 95% CI: 0.32, 114.62; p‐value: 0.23). When assessing for a modified Rankin scale at 90 days post‐discharge, binarized as above, a lower severity pcASPECTS showed 4.36 times the odds of a good outcome (OR: 4.36; 95% CI: 0.27, 69.40; p‐value: 0.30). Conclusions Our study revealed that pcASPECTS on admission may help predict clinical outcomes in patients receiving EVT for BAO and therefore could be used as a guide for medical and endovascular management. These findings have far‐reaching applicability but will require larger studies to confirm significant clinical benefit.

Endovascular Stroke Therapy for Posterior Circulation Acute Ischemic Stroke Has Diminishing Benefit with Additional Passes

Background The relationship between pass number during endovascular stroke therapy (EST) and outcomes in anterior circulation large vessel occlusion (LVO) acute ischemic stroke (AIS) has been well studied. However, the association between EST attempts and outcomes for patients with posterior circulation LVO remains unclear. Methods From our prospectively maintained multicenter registry, we identified consecutive patients with LVO AIS who underwent EST. The number of thrombectomy passes and per‐pass reperfusion grades (thrombolysis in cerebral infarction) were recorded prospectively at the time of procedure. The primary outcome was the association of number of EST passes and functional independence (modified Rankin scale 0–2) at 90 days. Secondary outcomes included likelihood of attaining substantial reperfusion (thrombolysis in cerebral infarction 2b‐3). Results Among 894 patients with LVO AIS who underwent EST, median age was 68 [interquartile range 58–78], 49% were female, and median National Institutes of Health Stroke Scale was 16 [interquartile range 11–21]. Of this cohort, 86 (9.6%) had posterior circulation LVO, including 65 (7%) with basilar artery occlusion and 9 (1%) with vertebral artery occlusion. The diminishing benefit on successful reperfusion of additional passes was similar for anterior and posterior circulation AIS. Among patients with posterior circulation stroke, successful reperfusion with fewer passes was associated with greater likelihood of good functional outcome at 90 days (40.0% versus 4.8% modified Rankin scale 0–2 with 1–2 versus 3+ passes; P = 0.003). The likelihood of good outcome in patients with posterior circulation LVO treated with EST and successful reperfusion in 1–2 passes was comparable to patients with anterior circulation LVO (40.0% versus 40.2%, posterior versus anterior; P = 0.553). Conclusions The number of EST passes has a significant association with functional independence at 90 days for patients with posterior circulation LVO AIS. After 2 passes, there is significantly reduced benefit conferred by additional passes. Overall clinical outcomes in patients with successful reperfusion with 1–2 passes were similar in patients with posterior circulation compared with anterior circulation LVO.