Intravenous Thrombolysis Before Endovascular Treatment in Posterior Circulation Occlusions: A MR CLEAN Registry Study.

BACKGROUND: The effectiveness of intravenous thrombolysis (IVT) before endovascular treatment (EVT) has been investigated in randomized trials and meta-analyses. These studies mainly concerned anterior circulation occlusions. We aimed to investigate clinical, technical, and safety outcomes of IVT before EVT in posterior circulation occlusions in a nationwide registry. METHODS: Patients were included from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands), a nationwide, prospective, multicenter registry of patients with acute ischemic stroke due to a large intracranial vessel occlusion receiving EVT between 2014 and 2019. All patients with a posterior circulation occlusion were included. Primary outcome was a shift toward better functional outcome on the modified Rankin Scale at 90 days. Secondary outcomes were favorable functional outcome (modified Rankin Scale scores, 0-3), occurrence of symptomatic intracranial hemorrhages, successful reperfusion (extended Thrombolysis in Cerebral Ischemia ≥2B), first-attempt successful reperfusion, and mortality at 90 days. Regression analyses with adjustments based on univariable analyses and literature were applied. RESULTS: A total of 248 patients were included, who received either IVT (n=125) or no IVT (n=123) before EVT. Results show no differences in a shift on the modified Rankin Scale (adjusted common odds ratio, 1.04 [95% CI, 0.61-1.76]). Although symptomatic intracranial hemorrhages occurred more often in the IVT group (4.8% versus 2.4%), regression analysis did not show a significant difference (adjusted odds ratio, 1.65 [95% CI, 0.33-8.35]). Successful reperfusion, favorable functional outcome, first-attempt successful reperfusion, and mortality did not differ between patients treated with and without IVT. CONCLUSIONS: We found no significant differences in clinical, technical, and safety outcomes between patients with a large vessel occlusion in the posterior circulation treated with or without IVT before EVT. Our results are in line with the literature on the anterior circulation.

MRI Assessment of Brain Frailty and Clinical Outcome in Patients With Acute Posterior Perforating Artery Infarction.

BACKGROUND: Global brain health has gained increasing attention recently. Imaging markers of brain frailty have been related to functional outcomes in previous studies on anterior circulation; however, little data are available on imaging markers and posterior circulation. PURPOSE: To investigate the impact of brain frailty on functional outcomes in patients with acute perforating artery infarction (PAI) of the posterior circulation. STUDY TYPE: Prospective. POPULATION: One hundred patients (60.78 ± 9.51 years, 72% men) with acute posterior circulation PAI (determined by diffusion-weighted magnetic resonance imaging (MRI)/time-of-flight MR angiography). FIELD STRENGTH/SEQUENCE: T1- and T2-weighted fast spin echo, T2-weighted fluid-attenuated inversion recovery, diffusion-weighted echo planar, gradient echo (susceptibility-weight imaging), and 3D time-of-flight MR angiography sequences at 3.0 T. ASSESSMENT: Periventricular and deep white matter hyperintensities (WMH), enlarged perivascular spaces (EPVS) in the basal ganglia and centrum semiovale area, lacunes, cerebral microbleeds (CMB), and total brain frailty score by calculating the above imaging characters were rated visually by three radiologists with 9, 10, and 11 years of experience and one neuroradiologist with 12. Infarction volume was assessed using baseline diffusion-weighted imaging (DWI) data obtained within 24 hours of symptom onset. A modified Rankin Scale (mRS) score >1 on day 90 defined an adverse functional outcome. Associations between the imaging markers of brain frailty and functional outcomes were assessed. STATISTICAL TESTS: Fisher's exact test, Mann-Whitney U test, and multivariable binary logistic regression. A P value <0.05 was considered statistically significant. RESULTS: Adverse prognoses (mRS > 1) were observed in 34 (34%) patients. Infarction volume, periventricular WMH, deep WMH, basal ganglia EPVS, CMB, and the brain frailty score were significantly associated with adverse functional outcomes. An increased brain frailty score was significantly associated with unfavorable mRS score on day 90 (odds ratio 1.773, 95% confidence interval 1.237-2.541). DATA CONCLUSION: Advanced MRI imaging markers of brain frailty, individually or combined as a total brain frailty score, were associated with worse functional outcomes after acute posterior circulation PAI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 3.

Do monosymptomatic stroke patients with dizziness present a vestibular syndrome without nystagmus? An underestimated entity.

BACKGROUND AND PURPOSE: Vestibular symptoms are common in emergency department (ED) patients and have various causes, including stroke. Accurate identification of stroke in patients with vestibular symptoms is crucial for timely management. We conducted a prospective cross-sectional study from 2015 to 2019 to determine stroke prevalence and associated symptoms in ED patients with vestibular symptoms, aiming to improve diagnosis and outcomes. METHODS: As part of the DETECT project, we screened 1647 ED patients with acute vestibular symptoms. Following a retrospective analysis of 961 head and neck magnetic resonance imaging (MRI) scans, we included 122 confirmed stroke cases and assessed them for vestibular signs and symptoms. RESULTS: Stroke prevalence in dizzy patients was 13% (122/961 MRI scans). Most patients (95%) presented with acute vestibular symptoms with or without nystagmus, whereas 5% had episodic vestibular syndrome (EVS). Nystagmus was present in 50% of stroke patients. Eighty percent had a purely posterior circulation stroke, and nystagmus was absent in 46% of these patients. Seven patients (6%) had lesions in both the anterior and posterior circulation. Vertigo was experienced by 52% regardless of territory. CONCLUSIONS: A stroke was identified in 13% of ED patients presenting with acute vestibular symptoms. In 5%, it was EVS. Most strokes were in the posterior circulation territory; vertigo occurred with similar frequency in anterior and posterior circulation stroke, and absence of nystagmus was common in both.

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

BACKGROUND AND PURPOSE: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Utilizing machine learning to facilitate the early diagnosis of posterior circulation stroke.

BACKGROUND: Posterior Circulation Syndrome (PCS) presents a diagnostic challenge characterized by its variable and nonspecific symptoms. Timely and accurate diagnosis is crucial for improving patient outcomes. This study aims to enhance the early diagnosis of PCS by employing clinical and demographic data and machine learning. This approach targets a significant research gap in the field of stroke diagnosis and management. METHODS: We collected and analyzed data from a large national Stroke Registry spanning from January 2014 to July 2022. The dataset included 15,859 adult patients admitted with a primary diagnosis of stroke. Five machine learning models were trained: XGBoost, Random Forest, Support Vector Machine, Classification and Regression Trees, and Logistic Regression. Multiple performance metrics, such as accuracy, precision, recall, F1-score, AUC, Matthew's correlation coefficient, log loss, and Brier score, were utilized to evaluate model performance. RESULTS: The XGBoost model emerged as the top performer with an AUC of 0.81, accuracy of 0.79, precision of 0.5, recall of 0.62, and F1-score of 0.55. SHAP (SHapley Additive exPlanations) analysis identified key variables associated with PCS, including Body Mass Index, Random Blood Sugar, ataxia, dysarthria, and diastolic blood pressure and body temperature. These variables played a significant role in facilitating the early diagnosis of PCS, emphasizing their diagnostic value. CONCLUSION: This study pioneers the use of clinical data and machine learning models to facilitate the early diagnosis of PCS, filling a crucial gap in stroke research. Using simple clinical metrics such as BMI, RBS, ataxia, dysarthria, DBP, and body temperature will help clinicians diagnose PCS early. Despite limitations, such as data biases and regional specificity, our research contributes to advancing PCS understanding, potentially enhancing clinical decision-making and patient outcomes early in the patient's clinical journey. Further investigations are warranted to elucidate the underlying physiological mechanisms and validate these findings in broader populations and healthcare settings.

Posterior circulation ischemic stroke: radiomics-based machine learning approach to identify onset time from magnetic resonance imaging.

PURPOSE: Posterior circulation ischemic stroke (PCIS) possesses unique features. However, previous studies have primarily or exclusively relied on anterior circulation stroke cases to build machine learning (ML) models for predicting onset time. To date, there is no research reporting the effectiveness and stability of ML in identifying PCIS onset time. We aimed to build diffusion-weighted imaging-based ML models to identify the onset time of PCIS patients. METHODS: Consecutive PCIS patients within 24 h of definite symptom onset were included (112 in the training set and 49 in the independent test set). Images were processed as follows: volume of interest segmentation, image feature extraction, and feature selection. Five ML models, naïve Bayes, logistic regression, tree ensemble, k-nearest neighbor, and random forest, were built based on the training set to estimate the stroke onset time (binary classification: ≤ 4.5 h or > 4.5 h). Relative standard deviations (RSD), receiver operating characteristic (ROC) curves, and the calibration plot was performed to evaluate the stability and performance of the five models. RESULTS: The random forest model had the best performance in the test set, with the highest area under the curve (AUC, 0.840; 95% CI: 0.706, 0.974). This model also achieved the highest accuracy, sensitivity, specificity, positive predictive value, and negative predictive value (83.7%, 64.3%, 91.4%, 75.0%, and 86.5%, respectively). Furthermore, the model had high stability (RSD = 0.0094). CONCLUSION: The PCIS case-based ML model was effective for estimating the symptom onset time and achieved considerably high specificity and stability.

Analysis of relevant factors affecting the prognosis of mechanical thrombectomy in patients with acute posterior circulation large vessel occlusion cerebral infarction.

OBJECTIVE: To explore the factors affecting the prognosis of patients with acute posterior circulation large vessel occlusion cerebral infarction (PCO) after mechanical thrombectomy. METHOD: A retrospective study was conducted on a total of 58 patients who received thrombectomy and presented within 24 h of onset with PCO from 31 September 2020 to 31 December 2022. They were divided into two groups based on a 90-day mRS score(The mRS score of 0-3 was defined as a good prognosis, and 4-6 was defined as a poor prognosis).A univariate analysis was conducted on baseline data such as age and patient past medical history, as well as extended cerebral infarction thrombolysis grade (eTICI grade) and incidence of symptomatic intracranial hemorrhage (sICH) after surgery, for the groups with good prognosis and poor prognosis. Factors affecting the 90-day prognosis of patients were also analyzed in subgroups. RESULTS: The preoperative National Institutes of Health Stroke Scale (NIHSS score)[21(12-35) vs 35(35-35)], postoperative 24-h NIHSS score[13(8-22) vs 35(35-35)], computed tomography (CT)[9(9-10) vs 6.5(6-7.75)] and computed tomography (CTP) brain blood volume (CBV)[9(8-10) vs 4(2-7.75)], cerebral blood flow (CBF)[7(4.5-9) vs 2(1-4)], time to peak (Tmax) [1(0.5-4) vs 0(0-1.75)] imaging of the posterior circulation Alberta stroke project early CT score (pc-ASPECTS score), Different locations of vascular occlusion, time from femoral artery puncture to vascular recanalization(64.96 ± 33.47 vs 92.68 ± 53.17). The differences in the conversion rate of postoperative intracranial hemorrhage(0 vs 16.1%) and the incidence of sICH(0 vs 12.9%) were statistically significant (P < 0.05). The subgroup analysis showed that vascular occlusion site, preoperative CBV pc-ASPECTS scores, and postoperative sICH occurrence were related to the 90-day prognosis of patients, and the differences were statistically significant (P < 0.05). CONCLUSIONS: Some factors that can affect the prognosis of mechanical thrombectomy in patients with acute posterior circulation large vessel occlusion cerebral infarction. Preoperative clinical symptoms and imaging evaluation have certain evaluation values for prognosis.

Meta-analysis of clinical and safety profiles after reperfusion therapy in acute posterior circulation strokes: insights and implications.

BACKGROUND: Posterior circulation stroke (PCS) accounts for approximately 20% of all acute ischemic strokes. The optimal reperfusion therapy for PCS management remains uncertain. PURPOSE: To evaluate the prevalence and outcomes of intravenous thrombolysis (IVT), endovascular thrombectomy (EVT), and bridging therapy in PCS patients. MATERIAL AND METHODS: We conducted a meta-analysis of 19 studies examining reperfusion therapy outcomes in PCS patients, including 9765 individuals. We pooled prevalence data and assessed associations between reperfusion therapies and clinical, safety, and recanalization outcomes using random-effects models. RESULTS: The pooled prevalence of reperfusion therapies post-acute PCS was 39% for IVT, 54% for EVT, and 48% for bridging therapy. EVT was associated with significantly higher odds of favorable functional outcomes (modified Rankin Score [mRS] 0-3) at 90 days compared to standard medical therapy (odds ratio [OR] = 5.68; 95% confidence interval [CI]=2.07-15.59; P = 0.001). Conversely, bridging therapy was linked to reduced odds of favorable functional outcomes at 90 days compared to EVT (OR = 0.35; 95% CI=0.26-0.47; P < 0.001). Bridging therapy was also significantly associated with lower odds of good functional outcomes (mRS 0-2) (OR = 0.25; 95% CI=0.11-0.54; P < 0.001), reduced risk of symptomatic intracranial hemorrhage (OR = 0.26; 95% CI=0.07-0.68; P = 0.009), lower mortality (OR = 0.13; 95% CI=0.04-0.44; P = 0.001), and less successful recanalization (OR = 0.35; 95% CI=0.13-0.94; P = 0.038) relative to EVT. CONCLUSION: Our meta-analysis underscores the favorable outcomes associated with EVT in PCS cases. With notable reperfusion rates, understanding factors influencing PCS outcomes can inform patient selection and prognostic considerations.

Ruptured aneurysm in collateral arteries with blood-flow impairment of posterior inferior cerebellar artery: a report of three cases.

Herein, we report three cases of cerebellar hemorrhage due to a ruptured small aneurysm located on a collateral artery compensating for one or more stenotic or occluded major cerebellar arteries. In each case, endovascular distant parent artery occlusion of both the collateral artery and aneurysm was performed to prevent rebleeding. A ruptured small aneurysm in a collateral artery may be observed in patients with hemorrhage in an atypical cerebellar region, especially in cases of stenosis or occlusion of the vertebral artery or posterior inferior cerebellar artery. Thus, cerebral angiography is recommended to rule out collateral artery aneurysm.

Basilar artery perforator aneurysms: a comparison with non-perforator saccular aneurysms.

BACKGROUND: Basilar artery perforator aneurysms (BAPAs) are rare. There is no systematic description of their presentation, imaging, natural history and outcomes and how these compare to conventional non-perforator aneurysms. Thus, the authors in this study aimed to compare BAPAs to non-perforator aneurysms. METHODS: Cases were identified from a prospective neurovascular database, notes and imaging retrospectively reviewed and compared to a consecutive series of patients with non-perforator aneurysms. Blood volume on CT and vessel wall imaging (VWI) were compared to controls. RESULTS: 9/739 patients with aneurysmal subarachnoid haemorrhage (aSAH) harboured BAPAs. Compared to 103 with aSAH from posterior circulation aneurysms, they were more likely to be male (6/9, p = 0.008), but of equal severity (4/9 poor grade, p = 0.736) and need of CSF drainage (5/9, p = 0.154). Blood volume was similar to controls (30.2 ml vs 26.7 ml, p = 0.716). 6/9 BAPAs were initially missed on CTA. VWI showed thick (2.9 mm ± 2.7) bright enhancement (stalk ratio 1.05 ± 0.12), similar to controls with ruptured aneurysms (0.95 ± 0.23, p = 0.551), and greater than unruptured aneurysms (0.43 ± 0.11, p < 0.001). All were initially managed conservatively. Six thrombosed spontaneously. Three grew and had difficult access with few good endovascular options and were treated through a subtemporal craniotomy without complication. None rebled. At 3 months, all presenting in poor grade were mRS 3-4 and those in good grade mRS 1-2. CONCLUSIONS: Despite their small size, BAPAs present with similar volume SAH, WFNS grade and hydrocephalus to other aneurysms. They are difficult to identify on CTA but enhance strikingly on VWI. The majority thrombosed. Initial conservative management reserving treatment for growth was associated with no rebleeds or complications.

Clinical characteristics, Risk factors, and outcomes of Posterior circulation stroke: A retrospective study between younger and older adults in Saudi Arabia.

INTRODUCTION: Posterior circulation stroke (PCS) may be less prevalent than its anterior counterpart but contributes to substantial morbidity and mortality. The aim was to characterize PCS's demographics, clinical presentation, management, and outcomes between younger and older adults in Saudi Arabia. METHODS: This retrospective cohort study was conducted at two tertiary medical centers in Saudi Arabia between March 2016 and December 2020. All patients who presented with symptoms of posterior circulation stroke and had positive brain imaging were included. RESULTS: The study involved 160 posterior circulation stroke patients, stratified into two age groups: 71 patients aged 18-59 years and 89 patients aged 60 years and above. The mean age of the entire cohort was 60.9 years, and 77 % were males. Hypertension was more prevalent in the older age group (88 % vs. 69 %, p=0.005), and smoking was significantly higher among younger patients (38 % vs. 15 %; p=0.0009). Only 22.4 % received thrombolysis and/or thrombectomy. Most strokes involved the posterior cerebral artery (45.6 %). Large artery atherosclerosis was the most common subtype. At discharge, younger patients had higher NIHSS compared to older patients. CONCLUSION: Our investigation of 160 PCS patients in Saudi Arabia uncovers notable trends: a mere 22.4 % received thrombolysis and/or thrombectomy and a significant prevalence of posterior cerebral artery involvement due to large artery atherosclerosis. The study further reveals younger patients disproportionately had severe outcomes. Highlighting the need for improved stroke care and heightened awareness, this research contributes vital data to an underexplored domain, urging further study to optimize care and understand PCS dynamics in Saudi Arabia.

Intravenous alteplase versus tenecteplase in patients with acute posterior circulation strokes: A secondary analysis from the AcT randomized controlled trial.

OBJECTIVES: There are limited data available demonstrating the safety and efficacy of intravenous tenecteplase versus alteplase in patients with acute ischemic stroke in the posterior circulation. MATERIALS AND METHODS: This is a post-hoc analysis of the Alteplase compared to Tenecteplase (AcT) pragmatic, phase 3, registry-linked randomized controlled trial. Patients with any posterior circulation vessel occlusion on baseline imaging were included. Study outcomes included 90-day modified Rankin Scale (mRS) 0-1, mRS 0-2, ordinal mRS, death within 90 days, 24 h symptomatic intracerebral haemorrhage (sICH) and successful reperfusion/recanalization. Mixed effects regression adjusting for age, sex and stroke severity was used to analyze differences in outcomes between patients administered tenecteplase vs. alteplase. Further, sensitivity analysis was conducted for basilar artery occlusion (BAO) alone. RESULTS: Of 1577 patients, 136 (8.6 %, 77:alteplase, 59:tenecteplase) had posterior circulation stroke. Baseline characteristics were similar[median age 71 (IQR 60-81) vs. 72 (IQR 65-82) years, 57.1 % vs. 67.8 % males, median baseline NIHSS 7 (IQR 4-12) vs. 7 (IQR 4-16) in alteplase vs. tenecteplase arms, respectively]. 28 patients (20.6 %, 16:alteplase, 12:tenecteplase arm) underwent EVT. The median 90-120 days mRS was 2 (IQR 1-4). There were no differences between alteplase and tenecteplase for 90-d mRS 0-1 (adjRR 0.93;95 %CI 0.63-1.36), 90-day mRS 0-2 (adjRR 0.95; 95 %CI 0.72-1.26), sICH (RR 0.65; 95 %CI 0.06-7.02) and mortality (RR 1.21; 95 %CI 0.61-2.38). Successful reperfusion eTICI 2b-3 and successful recanalization rAOL 2b-3 was achieved in 23/28 (82 %, 12:alteplase, 11:tenecteplase) and in 16/28 (57 %, 14:alteplase, 12:tenecteplase), respectively. Similar results were seen in 31 patients (22.8 %) with BAO. CONCLUSION: Intravenous tenecteplase has a similar effect on outcome as alteplase, without increased safety concerns in patients with acute posterior circulation strokes.

Intravenous thrombolysis for ischemic stroke in the posterior circulation: A systematic review and meta-analysis.

OBJECTIVES: Intravenous thrombolysis (IVT) is recommended in patients with ischemic stroke in the anterior and posterior circulation. Neurological outcomes due to posterior circulation strokes (PCS) without treatment remain poor. Our aim was to overview the literature on outcomes of IVT and conservative treatment in PCS, based on a systematic review and meta-analysis. METHODS: A systematic literature search was performed on February 27th 2023. Outcome measures included favorable functional outcome at 90 days (modified Rankin Scale [mRS] 0-2), mortality at 90 days, and symptomatic intracranial hemorrhages (sICH). Weighted averages with DerSimonian-Laird approach was used to analyze the data. Subgroup analyses by time window were performed: standard time window (<4.5 hours after symptom onset) and extended time window (>4.5 hours). Analyses were performed using R. RESULTS: Eight prospective and four retrospective cohort studies were included (n = 1589 patients); no studies with conservative treatment were eligible. The pooled weighted probability regarding favorable functional outcome after IVT was 63 % (95 %CI:0.45-0.78), for mortality 19 % (95 %CI:0.11-0.30), and for sICH 4 % (95 %CI:0.02-0.07). Subgroup analyses showed higher probabilities on achieving favorable functional outcomes for patients treated in the standard (77 %; 95 %CI:0.62-0.88) compared to the extended time window (38 %; 95 %CI:0.29-0.48) with RR = 1.93 (95 %CI:1.66-2.24). Lower probabilities regarding mortality at 90 days and sICH were seen in patients treated in standard compared to extended time window (RR = 0.42, 95 %CI:0.34-0.51 and RR = 0.27, 95 %CI:0.16-0.45, respectively). CONCLUSIONS: IVT in patients with PCS seems to be safe and effective in standard and extended time window. The effect of IVT is higher in the standard time window.

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.

INTRODUCTION: The best anesthetic choice for patients with acute posterior circulation stroke during endovascular treatment (EVT) remains uncertain. METHOD: We 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. RESULTS: A 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. CONCLUSIONS: Our 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.

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

OBJECTIVE: This 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. METHODS: This 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. RESULTS: The 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. CONCLUSION: For 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.

Exploring vertebral artery stump syndrome: An overlooked cause of posterior ischemic strokes. A narrative review of current management options.

INTRODUCTION: Stump syndrome is defined as a clinical syndrome resulting from a distal intracranial vessel embolic stroke due to an extracranial vessel occlusion. Similar to the anterior circulation, the recurrence of ischemic strokes in territories supplied by the posterior circulation in the presence of vertebral artery occlusion is termed Vertebral Artery Stump Syndrome (VASS). MATERIAL AND METHODS: We conducted a literature review, identifying 72 patients with transient ischemic attacks (TIAs) or ischemic strokes attributed to VASS, according to Kawano criteria. We categorized all patients in two groups focusing on the therapeutic management those who underwent primary medical treatment and those who received endovascular or surgical treatment either in acute or chronic phase. RESULTS: In the anticoagulant therapy group, only 1 patient had a stroke recurrence. Among the 4 on antiplatelets, all had recurrences, but 3 benefited from switching to anticoagulants or endovascular therapy. In the endovascular therapy group, worse outcomes were linked to acute large vessel occlusion. Endovascular treatment of the vertebral artery, in a chronic phase, was explored in literature for recurrent TIAs or minor strokes suggesting that this could be a viable therapeutic alternative when medical treatment failed in preventing recurrence of ischemic stroke. CONCLUSIONS: Some studies suggest that anticoagulant medical therapy may be beneficial for VASS and endovascular therapy has also been reported for selected patients. However, data on treatment outcomes and prognosis are still underreported, making treatment decisions challenging. Randomized Controlled Trials are needed to establish the optimal treatment approach.

Differences in intracranial atherosclerosis plaque between posterior circulation and anterior circulation on high-resolution magnetic resonance imaging: A systematic review and meta-analysis.

OBJECTIVE: The clinical characteristics and mechanisms of stroke caused by anterior circulation atherosclerotic plaques (ACAPs) and posterior circulation atherosclerotic plaques (PCAPs) are distinct. We aimed to compare the differences in vulnerability, morphology, and distribution between ACAPs and PCAPs based on hign-resolution magnetic resonance imaging (HR-MRI). MATERIALS AND METHODS: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang database were retrieved from inception through May 2023. Meta-analysis was performed by R 4.2.1 software. The quality of the literature was assessed by the Agency for Healthcare Research and Quality (AHRQ). Subgroup analysis was conducted to explore the heterogeneity of the pooled results. RESULTS: There were a total of 13 articles, including 1194 ACAPs and 1037 PCAPs. The pooled estimates demonstrated that the incidence of intraplaque hemorrhage in the PCAPs was higher (OR 1.72, 95%CI 1.35-2.18). The plaque length (SMD 0.23, 95%CI 0.06-0.39) and remodeling index (SMD 0.29, 95%CI 0.14-0.44) of PCAPs were larger than those in ACAPs. However, there were no evident differences in significant enhancement or stenosis degree between the two groups. CONCLUSION: There were more unstable features in PCAPs, highlighting an elevated risk of recurrent ischemic stroke in the posterior circulation. Furthermore, PCAPs were prone to developing penetrating artery disease due to their wider distribution. Nevertheless, posterior circulation arteries exhibited a greater propensity for outward remodeling, which may lead treatment team to miss the optimal intervention stage by being overlooked on angiographic detection.

Eyes wide shut: Horizontal direction changing nystagmus in a left cerebellar-medullary stroke. Favourable outcome after thrombolysis.

OBJECTIVE: To describe a patient with a posterior inferior cerebellar artery stroke exhibiting a horizontal direction changing nystagmus with a complex clinical phenotype. MATERIALS AND METHODS: A 78-year-old man presented with acute vertigo and gait imbalance. He was dysphagic and ataxic on the left side. He had a fast, small-amplitude right-beating nystagmus in the primary gaze position and in the gaze towards the right. Towards the left, a coarse left-beating nystagmus was seen. RESULTS: Radiographic leftwards ocular deviation was evident on admission CT. Intravenous fibrinolysis was administered. 48-hour Holter-EKG, transthoracic ecochardiogram, and transcranial doppler were unremarkable. Brain MRI demonstrated an acute stroke involving the left medulla and cerebellum, mainly within the territory of the ipsilateral posterior inferior cerebellar artery. DISCUSSION AND CONCLUSIONS: Horizontal direction changing nystagmus can arise secondary to central lesions as brainstem strokes, it can be spontaneous or gaze-evoked and characteristically remains unchanged after fixation removal. In our case, the vestibular spontaneous and contralesional nystagmus was likely related to lower-brainstem damage; on the other hand, the ipsilesional gaze-evoked nystagmus might be related to lesions of the nucleus prepositus hypoglossi and/or cerebellum, both playing an important role in gaze-holding. Our findings suggest that central lesions with concurrent involvement of the ipsilateral vestibulo-ocular and horizontal gaze-holding pathways can cause direction changing nystagmus with complex phenotypes.

Posterior vascular anatomy of the encephalon: a comprehensive review.

PURPOSE: This article presents a comprehensive exploration of neurovascular anatomy of the encephalon, focusing specifically on the intricate network within the posterior circulation and the posterior fossa anatomy; enhancing understanding of its dynamics, essential for practitioners in neurosurgery and neurology areas. METHOD: A profound literature review was conducted by searching the PubMed and Google Scholar databases using main keywords related to neurovascular anatomy. The selected literature was meticulously scrutinized. Throughout the screening of pertinent papers, further articles or book chapters were obtained through additional assessment of the reference lists. Furthermore, four formalin-fixed, color latex-injected cadaveric specimens preserved in 70% ethanol solution were dissected under surgical microscope (Leica Microsystems Inc, 1700 Leider Ln, Buffalo Grove, IL 60089, USA), using microneurosurgical as well as standard instruments, and a high-speed surgical drill (Stryker Instruments 1941 Stryker Way Portage, MI 49002, USA). Ulterior anatomical dissection was performed. RESULTS: Detailed examination of the basilar artery (BA), a common trunk formed by the union of the left and right vertebral arteries, denoted a tortuous course across the basilar sulcus. Emphasis is then placed on the Posterior Inferior Cerebellar Artery (PICA), Anterior Inferior Cerebellar Artery (AICA) and Superior Cerebellar Artery (SCA). Each artery's complex course through the posterior fossa, its divisions, and potential stroke-related syndromes are explored in detail. The Posterior Cerebral Artery (PCA) is subsequently unveiled. The posterior fossa venous system is explained, categorizing its channels. A retrograde exploration traces the venous drainage back to the internal jugular vein, unraveling its pathways. CONCLUSION: This work serves as a succinct yet comprehensive guide, offering fundamental insights into neurovascular anatomy within the encephalon's posterior circulation. Intended for both novice physicians and seasoned neuroanatomists, the article aims to facilitate a more efficient clinical decision-making in neurosurgical and neurological practices.

Patterns and Implications of Intracranial Atherosclerosis in Anterior and Posterior Circulation Identified by High-Resolution Vessel Wall Imaging.

INTRODUCTION: Anterior and posterior circulation atheroscleroses differ in vascular risk factors and stroke patterns. Posterior circulation stroke has worse clinical outcomes. However, few studies described the differentiation of plaque features between anterior and posterior circulation atheroscleroses via high-resolution vessel wall imaging (HR-VWI). We aimed to compare the plaque imaging features between anterior and posterior circulations to highlight the relevance of plaque imaging features to clinical events of ischemic stroke. METHODS: Prospective data from a HR-VWI cohort of adult patients with acute ischemic stroke or transient ischemic attack were retrospectively analyzed. Quantitative and qualitative measurements of atherosclerotic plaques along the middle cerebral arteries (MCAs), the basilar artery (BA), and the vertebral arteries (VAs) were conducted on HR-VWI. Vessels with stenotic degrees over 30% were identified on the matched time-of-flight magnetic resonance angiography (TOF-MRA) and visually classified into normal, irregular, stenotic, and occluded. The sensitivity, specificity, positive and negative predictive values for TOF-MRA in detecting abnormal vessels were calculated by using quantification on the basis of HR-VWI findings as the reference standard. RESULTS: One hundred and one patients (median age, 64 years old; 62.4% males) were included in this study. A total of 292 plaques were identified, with 152 in the MCAs, 35 in the BA, and 105 in the VAs. The VAs possessed significantly higher enhancement index (EI) (median 38.37 vs. 18.40, p <0.001), more plaques with positive remodeling (76.2% vs. 57.2%, p = 0.002) and intraplaque hypo-intensity (43.8% vs. 12.5%, p <0.001) than the MCAs. The MCAs presented with more intraplaque hemorrhage (IPH) (20.4% vs. 8.6%, p = 0.014) than the VAs. The sensitivity and specificity of TOF-MRA for evaluating luminal stenosis were 89.0 (82.5-93.4) and 66.7 (24.1-94.0) in anterior circulation, respectively, and were 75.2 (66.7-82.2) and 27.3 (7.3-60.7) in posterior circulation, respectively. CONCLUSION: Our findings might elucidate the clinical events and outcomes in anterior and posterior circulation stroke. Posterior circulation atherosclerosis had higher EI and more plaques with hypo-intensity, suggesting a heavier atherosclerosis burden. Positive remodeling pattern in posterior circulation atherosclerosis might create an impression of "wider" vascular lumen, leading to possible underestimation of atherosclerosis burden of posterior circulation on TOF-MRA as compared to HR-VWI. Besides, anterior circulation atherosclerosis with IPH might be associated with plaque rupture and artery-to-artery embolism. Future studies are needed to verify these findings.