Periprocedural thromboembolic complications of LEO baby stent in endovascular treatment of intracranial aneurysms: Experience in 149 patients.

OBJECTIVE: To report periprocedural thromboembolic complications of LEO Baby stent-assisted coiling of wide-necked intracranial aneurysms and to analyze the possible influencing factors. METHODS: We retrospectively identified 149 patients with aneurysms who underwent LEO Baby stent-assisted embolization between October 2018 and March 2022. Clinical and radiographic data of patients were reviewed to determine whether a thromboembolic event had occurred. Multivariate logistic analysis was performed to identify significant factors associated with thromboembolic events. RESULTS: Successful stent deployment of the stent was achieved in all patients in the target artery. There were 66 patients (44.3%) with acutely ruptured aneurysms and 83 patients (55.7%) with unruptured aneurysms. Fourteen (9.4%, 95% confidence interval: 4.7%-14.1%) patients were confirmed to have developed a thromboembolic event, including nine patients with acute intraoperative thrombosis and five patients with postoperative thromboembolic events. The rate of thromboembolic events was 6.0% (5/83) in patients with unruptured aneurysms and 13.6% (9/66) in patients with acutely ruptured aneurysms. There was a trend toward an increased rate of thromboembolic events in patients with acute ruptured aneurysms (p = 0.087). Thromboembolic events were significantly associated with the parent-artery diameter (p = 0.010). CONCLUSIONS: Our study demonstrates a low rate of thromboembolic complications in unruptured aneurysms treated with LEO Baby stent. Thromboembolic events appear to be more common in ruptured aneurysms. A small diameter of the parent artery is associated with an increased risk of thromboembolic complications, and more relevant studies are still needed.

Assessment of Collateral Flow in Patients with Carotid Stenosis Using Random Vessel-Encoded Arterial Spin-Labeling: Comparison with Digital Subtraction Angiography.

BACKGROUND AND PURPOSE: Collateral circulation plays an important role in steno-occlusive internal carotid artery disease (ICAD) to reduce the risk of stroke. We aimed to investigate the utility of planning-free random vessel-encoded arterial spin-labeling (rVE-ASL) in assessing collateral flows in patients with ICAD. MATERIALS AND METHODS: Forty patients with ICAD were prospectively recruited. The presence and extent of collateral flow were assessed and compared between rVE-ASL and DSA by using Contingency (C) and Cramer V (V) coefficients. The differences in flow territory alterations stratified by stenosis ratio and symptoms, respectively, were compared between symptomatic (n = 19) and asymptomatic (n = 21) patients by using the Fisher exact test. RESULTS: Good agreement was observed between rVE-ASL and DSA in assessing collateral flow (C = 0.762, V = 0.833, both P < .001). Patients with ICA stenosis of ≥90% were more likely to have flow alterations (P < .001). Symptomatic patients showed a higher prevalence of flow alterations in the territory of the MCA on the same side of ICAD (63.2%), compared with asymptomatic patients (23.8%, P = .012), while the flow alterations in the territory of anterior cerebral artery did not differ (P = .442). The collateral flow to MCA territory was developed primarily from the contralateral internal carotid artery (70.6%) and vertebrobasilar artery to a lesser extent (47.1%). CONCLUSIONS: rVE-ASL provides comparable information with DSA on the assessment of collateral flow. The flow alterations in the MCA territory may be attributed to symptomatic ICAD.

Analysis of influencing factors of hemorrhagic transformation in patients with large vessel occlusion stroke after mechanical thrombectomy.

OBJECTIVE: To investigate the influencing factors of hemorrhagic transformation (HT) after mechanical thrombectomy (MT) in patients with large vessel occlusion (LVO) stroke. METHODS: From September 2018 to December 2022, 270 eligible patients with LVO who underwent MT in the First Affiliated Hospital of Nanjing medical University were selected for this retrospective study, and the patients were divided into an occurrence group and a non-occurrence group based on the immediate and 24 h postoperative head CT results. The influencing factors of postoperative HT after MT were identified using univariate and logistic regression analyses. A Nomogram was constructed using logistic variables of significance. Then, area under the ROC curve (AUC) was used to verify the predictive efficacy of the Nomogram, and decision curve analysis (DCA) was used to test the clinical validity of the Nomogram. RESULTS: HT occurred in 60 patients (23.70%) after MT. Logistic regression analysis showed that, male (OR=2.099, 95% CI: 1.051-4.193), age ≥71.5 years (OR=3.780, 95% CI: 1.836-7.782), preoperative NIHSS score ≥16.5 (OR=2.328, 95% CI: 1.112-4.873), operation time ≥58.5 min (OR=2.930, 95% CI: 1.294-6.634), and admission blood glucose ≥7.65 mmol/L (OR=4.915, 95% CI: 2.373-10.178) were risk factors for the occurrence of HT in patients with LVO stroke after MT. Admission serum magnesium ≥0.845 mmol/L (OR=0.225, 95% CI: 0.127-0.513) was a protective factor for the occurrence of HT in the patients after MT. The ROC curve showed that the AUC of the nomogram in the training set and test set were 0.849 (95% CI: 0.787-0.910) and 0.754 (95% CI: 0.634-0.874), respectively. DCA suggested that the nomogram revealed good clinical validity in the training and test sets. CONCLUSION: Sex, age, preoperative NIHSS score, operation time, blood glucose and serum magnesium levels at admission are influencing factors for the occurrence of HT in patients with LVO stroke after MT. The nomogram in this study has a good predictive efficiency, which can improve the diagnostic efficiency of HT after MT in patients with LVO stroke. Therefore, male patients with age ≥71.5 years, preoperative NIHSS score ≥16.5, operation time ≥58.5 min, admission blood glucose ≥7.65 mmol/L, and admission serum magnesium ≤0.845 mmol/L should raise awareness about the risk of HT after MT.

Radiomics features on computed tomography reflect thrombus histological age prior to endovascular treatment of acute ischemic stroke.

PURPOSE: To investigate the role of radiomics features in thrombus age identification and establish a CT-based radiomics model for predicting thrombus age of large vessel occlusion stroke patients. METHODS: We retrospectively reviewed patients with middle cerebral artery occlusion receiving mechanical thrombectomy from July 2020 to March 2022 at our center. The retrieved clots were stained with Hematoxylin and Eosin (H&E) and determined as fresh or older thrombi based on coagulation age. Clot-derived radiomics features were selected by least absolute shrinkage and selection operator (LASSO) regression analysis, by which selected radiomics features were integrated into the Rad-score via the corresponding coefficients. The prediction performance of Rad-score in thrombus age was evaluated with the area under the curve (AUC) of receiver operating characteristic (ROC) curve analysis. RESULTS: A total of 104 patients were included in our analysis, with 52 in training and 52 in validation cohort. Older thrombi were characterized with delayed procedure time, worse functional outcome and marginally associated with more attempts of device. We extracted 982 features from NCCT images. Following T test and LASSO analysis in training cohort, six radiomics features were selected, based on which the Rad-score was generated by the linear combination of features. The Rad-score showed satisfactory performance in distinguishing fresh with older thrombi, with the AUC of 0.873 (95 %CI: 0.777-0.956) and 0.773 (95 %CI: 0.636-0.910) in training and validation cohort, respectively. CONCLUSION: This study established and validated a CT-based radiomics model that could accurately differentiate fresh with older thrombi for stroke patients receiving mechanical thrombectomy.

Endovascular recanalization for symptomatic chronic internal carotid artery occlusion: proposal of a modified angiographic classification and clinical outcomes.

PURPOSE: To stratify angiographic images of chronic internal carotid artery occlusion (CICAO) into a newly modified angiographic classification, and identify suitable candidates for endovascular recanalization. METHODS: This study included 51 consecutive patients with symptomatic CICAO who underwent endovascular recanalization at our institution. Patients' clinical information, angiographic findings, procedural results, and outcomes were recorded. We attempted to stratify all angiographic images into categories based on morphological occlusive patterns and distal internal carotid artery (ICA) lumen reconstitution on digital subtraction angiography (DSA). RESULTS: Four types (I-IV) of CICAO were identified based on angiographic characteristics. We defined type I as having a tapered (IA) or blunt stump (IB) and distal ICA lumen reconstitution with collateral filling; type II as having no stump but with distal ICA lumen reconstitution; type III as having a tapered (IIIA) or blunt stump (IIIB) but no distal ICA lumen reconstitution; type IV as having no stump and no distal ICA lumen reconstitution. The rate of successful recanalization was 90.3 % for type I, 60.0 % for type II, 50.0 % for type III, 0 % for type IV, respectively (P = 0.002). The overall intraoperative complication rate was 11.8 %, and none of them led to severe neurological damage or death. The follow-up modified Rankin Scale (mRS) scores were significantly decreased in successfully revascularized patients, whilst there were no significant changes in the other failed patients. CONCLUSION: For symptomatic CICAO, our newly modified angiographic classification may be comprehensive and useful in selecting suitable patients for recanalization and grading the difficulty of the procedures.

Acute Vertebrobasilar Artery Occlusion with Underlying Atherosclerosis: Balloon Angioplasty Combined with Tirofiban as Initial Salvage Therapy.

OBJECTIVE: The optimal rescue endovascular treatment for patients with intracranial atherosclerotic stenosis in acute vertebrobasilar artery occlusion is not well established. We investigated the safety and efficacy of balloon angioplasty combined with tirofiban as the initial rescue strategy in these patients. METHODS: We retrospectively analyzed the records of 41 patients admitted between January 2014 and September 2022, with vertebrobasilar artery atherosclerotic occlusion. Balloon angioplasty in combination with tirofiban was used as the first-line salvage therapy after the failure of mechanical thrombectomy. The technical success rate, recanalization outcome, procedure-related complications, symptomatic intracranial hemorrhage, and functional outcome at 90 days were reviewed. RESULTS: Recanalization with a modified Thrombolysis in Cerebral Infarction grade of 2b-3 was achieved in 38 of the 41 patients (92.7%). Acute stents were deployed in 5 patients who did not achieve successful reperfusion after balloon angioplasty. Six patients (14.6%, 6/41) underwent stent angioplasty in the stable stage for severe residual stenosis detected on follow-up imaging. There was no procedure-related complication. Hemorrhagic transformation was detected on follow-up imaging in 11 patients (26.8%), while no symptomatic intracranial hemorrhage was recorded. Good functional outcome rate was 31.7% (13/41). CONCLUSIONS: Balloon angioplasty combined with intravenous tirofiban administration is a safe and effective salvage therapy in patients with acute atherosclerotic occlusion of the vertebrobasilar artery.

ASPECTS-based net water uptake outperforms target mismatch for outcome prediction in patients with acute ischemic stroke and late therapeutic window.

OBJECTIVE: To compare the prognostic value of net water uptake (NWU) and target mismatch (TM) on CT perfusion (CTP) in acute ischemic stroke (AIS) patients with late time window. METHODS: One hundred and nine consecutive AIS patients with anterior-circulation large vessel occlusion presenting within 6-24 h from onset/last seen well were enrolled. Automated Alberta Stroke Program Early CT Score-based NWU (ASPECTS-NWU) was calculated from admission CT. The correlation between ASPECTS-NWU and CTP parameters was assessed. Predictors for favorable outcome (modified Rankin Scale score ≤ 2) at 90 days were assessed using logistic regression analysis. The ability of outcome prediction between ASPECTS-NWU and TM (an ischemic core < 70 mL, a mismatch ratio ≥ 1.8, and an absolute difference ≥ 15 mL) was compared using receiver operating characteristic (ROC) curve. RESULTS: A higher level of ASPECTS-NWU was associated with a larger ischemic core (r = 0.66, p < 0.001) and a larger hypoperfusion volume (r = 0.38, p < 0.001). ASPECTS-NWU performed better than TM for outcome stratification (area under the curve [AUC], 0.738 vs 0.583, p = 0.004) and was the only independent neuroimaging marker associated with favorable outcomes compared with CTP parameters (odds ratio, 0.73; 95% confidence interval [CI] 0.62-0.87, p < 0.001). An outcome prediction model including ASPECTS-NWU and clinical variables (National Institutes of Health Stroke Scale scores and age) yielded an AUC of 0.828 (95% CI 0.744-0.893; sensitivity 65.4%; specificity 87.7%). CONCLUSION: ASPECTS-NWU performed better than TM for outcome prediction in AIS patients with late time window and might be an alternative imaging biomarker to CTP for patient selection. CLINICAL RELEVANCE STATEMENT: Automated Alberta Stroke Program Early CT Score-based net water uptake outperforms target mismatch on CT perfusion for the outcome prediction in patients with acute ischemic stroke and can be an alternative imaging biomarker for patient selection in late therapeutic window. KEY POINTS: • A higher ASPECTS-based net water uptake was associated with larger ischemic cores and hypoperfusion volumes on CT perfusion. • ASPECTS-based net water uptake outperformed target mismatch for outcome prediction in acute ischemic stroke with extended therapeutic window. • ASPECTS-based net water uptake can be an alternative biomarker to target mismatch for selecting acute ischemic stroke patients with late therapeutic window.

Effect of Truncal-Type Occlusion Based on Multiphase or Single-Phase Computed Tomographic Angiography in Predicting Intracranial Atherosclerotic Stenosis-Related Acute Middle Cerebral Artery Occlusion.

OBJECTIVE: To investigate whether truncal-type occlusion based on multiphase computed tomographic angiography (mpCTA) was more effective for predicting intracranial atherosclerotic stenosis-related occlusion (ICAS-O) than occlusion type based on single-phase computed tomographic angiography (spCTA) in patients with acute ischemic stroke with large-vessel occlusion (AIS-LVO) in the middle cerebral artery (MCA). METHODS: Data were retrospectively collected from 72 patients with AIS-LVO in the MCA between January 2018 and December 2019. The occlusion types included truncal-type and branching-site occlusions. The association between ICAS-O and occlusion type based on the 2 computed tomographic angiography patterns was analyzed, and receiver operating characteristic curves were plotted for assessment. The areas under the curve were compared to determine the difference between the predictive powers of truncal-type occlusion based on mpCTA and spCTA. RESULTS: Among the 72 patients, 16 were classified as having ICAS-O and 56 as having embolisms. In univariate analysis, truncal-type occlusion was significantly associated with ICAS-O ( P < 0.001 for mpCTA and P = 0.001 for spCTA). After multivariable analysis, truncal-type occlusion based on both mpCTA and spCTA remained independently associated with ICAS-O ( P = 0.002 for mpCTA and P = 0.029 for spCTA). The areas under the curve were 0.821 for mpCTA and 0.683 for spCTA; this difference was statistically significant ( P = 0.024). CONCLUSIONS: In patients with AIS-LVO in the MCA, truncal-type occlusion based on mpCTA enables more accurate detection of ICAS-O than that based on spCTA.

Corrigendum: Smaller baseline subcortical infarct volume predicts good outcomes in patients with a large core in early acute ischemic stroke after endovascular treatment.

[This corrects the article DOI: 10.3389/fnins.2023.1063478.].

Smaller baseline subcortical infarct volume predicts good outcomes in patients with a large core in early acute ischemic stroke after endovascular treatment.

Background: Patients with acute ischemic stroke (AIS) and a large core may benefit from endovascular treatment (EVT) in the early time window. Purpose: To examine the prognostic factors for good outcomes in patients with a large core (70-130 ml) after EVT. Materials and methods: We retrospectively reviewed 40 patients who met the criteria from October 2019 to April 2021. Based on the modified Rankin Score (mRS) at 90 days, the patients were divided into a good outcome group (mRS 0-2) and a poor outcome group (mRS 3-6). Baseline and procedural characteristics were collected for unilateral and multivariate regression analyses to explore the factors that influence good outcomes. In particular, the infarct territories were quantified as subcortical infarct volume (SIV) and cortical infarct volume (CIV). Results: Of the 40 patients included, good outcomes were observed in 11 (27.5%) patients. Younger age, smaller SIV and larger mismatch volume were noted in the good outcome group than in the poor outcome group (all P < 0.05). Multivariate logistic regression analysis showed that only a smaller SIV [odds ratio (OR) 0.801; 95% CI 0.644-0.996; P = 0.046] was an independent predictor for good outcomes. The receiver operating characteristic curve indicated a moderate value of SIV for predicting good outcomes, with an area under the receiver operating characteristic curve of 0.735 (95% CI 0.572-0.862; P = 0.007). Conclusion: Subcortical infarct volume was a potential useful predictor of good outcomes in patients with a large core after EVT in the early time window.

Emergency admission plasma D-dimer: a novel predictor for symptomatic intracranial hemorrhage after thrombectomy in acute ischemic stroke.

BACKGROUND: Symptomatic intracranial hemorrhage (sICH) is a common and severe complication in patients with acute ischemic stroke (AIS) after treatment with thrombectomy. OBJECTIVE: To explore the ability of admission plasma D-dimer levels to predict sICH after thrombectomy. METHODS: Between February 2018 and August 2021, consecutive patients with AIS who underwent thrombectomy at our single comprehensive stroke center were retrospectively enrolled. sICH was defined according to the criterion of the Heidelberg Bleeding Classification. Logistic regression analysis was performed to determine the risk factors of sICH. The overall discriminative ability of D-dimer levels in predicting sICH was evaluated by adopting a receiver operating characteristic (ROC) curve. RESULTS: Of the 395 enrolled patients, 48 (12.2%) had sICH. Patients with sICH were older (72.9 vs 69.3 years, P=0.037), more often female (62.5% vs 45.5%, P=0.027), had higher D-dimer levels (2.70 vs 0.74 mg/L, P<0.001), higher National Institutes of Health Stroke Scale score (20 vs 15, P<0.001), lower Alberta Stroke Program Early CT Score (8 vs 9, P<0.001), a higher proportion of internal carotid artery occlusions (56.2% vs 30.3%, P<0.001), and less commonly had large-artery atherosclerosis stroke etiology (12.5% vs 32.3%, P=0.010) than patients without sICH. After adjustment for potential confounders, D-dimer levels (adjusted OR=2.45, 95% CI 1.75 to 3.43, P<0.001) remained significantly associated with sICH. Based on the ROC, the D-dimer as a predictor for predicting sICH, presented with a specificity of 86.2%, a negative predictive value of 94.6%, and an area under the curve of 0.774. CONCLUSION: Elevated admission D-dimer levels are an independent predictor of sICH in patients with AIS after thrombectomy.

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

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

Predictors of ghost infarct core on baseline computed tomography perfusion in stroke patients with successful recanalization after mechanical thrombectomy.

OBJECTIVES: To assess the predictors of ghost infarct core (GIC) in stroke patients achieving successful recanalization after mechanical thrombectomy (MT), based on final infarct volume (FIV) calculated from follow-up diffusion-weighted imaging (DWI). METHODS: A total of 115 consecutive stroke patients who had undergone baseline computed tomography perfusion (CTP) scan, achieved successful recanalization after MT, and finished follow-up DWI evaluation were retrospectively enrolled. Ischemic core volume was automatically generated from baseline CTP, and FIV was determined manually based on follow-up DWI. Stroke-related risk factors and demographic, clinical, imaging, and procedural data were collected and assessed. Univariate and multivariate analyses were applied to identify the predictors of GIC. RESULTS: Of the 115 included patients (31 women and 84 men; median age, 66 years), 18 patients (15.7%) showed a GIC. The GIC group showed significantly shorter time interval from stroke onset to CTP scan and that from stroke onset to recanalization (both p < 0.001), but higher ischemic core volume (p < 0.001), hypoperfused area volume (p < 0.001), mismatch area volume (p = 0.006), and hypoperfusion ratio (p = 0.001) than the no-GIC group. In multivariate analysis, time interval from stroke onset to CTP scan (odds ratio [OR], 0.983; p = 0.005) and ischemic core volume (OR, 1.073; p < 0.001) were independently associated with the occurrence of GIC. CONCLUSIONS: In stroke patients achieving successful recanalization after MT, time interval from stroke onset to CTP and ischemic core volume are associated with the occurrence of GIC. Patients cannot be excluded from MT solely based on baseline CTP-derived ischemic core volume, especially for patients with a shorter onset time. KEY POINTS: • Ghost infarct core (GIC) was found in 15.7% of patients with acute ischemic stroke (AIS) in our study cohort. • GIC was associated with stroke onset time, volumetric parameters derived from CTP, and collateral status indicated by HIR. • Time interval from stroke onset to CTP scan and ischemic core volume were independent predictors of GIC.

Management of posterior circulation tandem occlusions in acute ischemic stroke: Recanalize the dominant vertebral artery with priority.

PURPOSE: To illustrate the characteristics of acute ostial vertebral artery (VA) and basilar artery (BA) tandem occlusions. The endovascular treatment strategy for ostial VA-BA tandem occlusion was reported. MATERIALS AND METHODS: We conducted a retrospective analysis of patients with ostial VA-BA tandem occlusion who underwent endovascular treatment in our center between November 2018 and February 2022. We preferred to recanalize the dominant vertebral artery with priority. The imaging characteristics, treatment strategy, clinical outcomes, and complications were analyzed. RESULTS: In total, 9 patients with ostial VA-BA tandem occlusion were enrolled in this study. All the VA-BA tandem occlusion was caused by acute occlusion of the dominant VA. Endovascular revascularization was performed through the occluded dominant VA in 8 patients and was performed through contralateral non-dominant VA in 1 patient. Successful recanalization (mTICI 2b/3 grade) was achieved in all 9 patients, and 5 patients (55.5%) achieved functional independence with a mRS score of 0-2 at 90 days. CONCLUSIONS: In this case series, the occurrence of ostial VA-BA tandem occlusions was mainly caused by acute occlusion of the dominant VA. Endovascular revascularization of ostial VA-BA tandem occlusions through occluded dominant VA was feasible and recommended.

Predictors of malignant middle cerebral artery infarction after endovascular thrombectomy: results of DIRECT-MT trial.

OBJECTIVES: Predictors of malignant middle cerebral artery infarction (mMCAi) in patients after intravenous thrombolysis were well documented, but the risk factors of mMCAi after endovascular thrombectomy (EVT) were not fully explored. Therefore, the present study aimed to investigate the predictors of mMCAi after EVT in stroke patients. METHODS: This was a secondary analysis of the DIRECT-MT trial. Patients who underwent EVT for the occlusions of MCA and/or intracranial internal carotid artery were analyzed. Primary outcome was the occurrence of mMCAi after EVT. Demographic, clinical, imaging, and treatment data were recorded, and multivariate logistic regression analysis was used to identify independent predictors. All of the candidate predictors were included, and forward elimination was applied to establish the most effective predictive model. Predictive ability and calibration of the model were assessed using the area under the receiver operating characteristic curve (AUC) and Hosmer-Lemeshow test, respectively. RESULTS: Of 559 enrolled patients, 74 (13.2%) patients developed mMCAi. Predictors of mMCAi included unsuccessful reperfusion, higher serum glucose, lower Alberta Stroke Project Early Computed Tomography Change Score (ASPECTS), higher clot burden score (CBS), lower collateral score, and higher pass number of thrombectomy device. AUC of predictive model integrating all independent variables was 0.836. The Hosmer-Lemeshow test showed appropriate calibration (p = 0.859). CONCLUSIONS: Reperfusion, serum glucose, ASPECTS, CBS, collateral, and pass number of thrombectomy device were associated with the occurrence of mMCAi in stroke patients after EVT, while alteplase treatment was not. Our findings might facilitate the early identification and management of stroke patients at a high risk of mMCAi. KEY POINTS: • A total of 13.2% of stroke patients with large vessel occlusion of anterior circulation developed mMCAi after EVT. • The occurrence of mMCAi had a definite negative impact on the outcome for stroke patients. • Reperfusion, serum glucose, ASPECTS, CBS, collateral score, and the pass number of thrombectomy device were associated with the occurrence of mMCAi after EVT in stroke patients.

Alberta Stroke Program Early CT Score and collateral status predict target mismatch in large vessel occlusion with delayed time windows.

BACKGROUND: The Alberta Stroke Program Early CT Score (ASPECTS) and collateral score (CS) are two readily available imaging metrics for the evaluation of acute ischemic stroke (AIS) with large vessel occlusion (LVO). OBJECTIVE: To investigate the predictive value of the ASPECTS combined with CS in detecting patients with CT perfusion (CTP) target mismatch in delayed time windows. METHODS: One hundred and sixty-four patients with LVO-AIS were included. ASPECTS was assessed on non-contrast CT (NCCT). CS was evaluated on single-phase CT angiography (sCTA). Target mismatch was defined as a CTP core volume ≤70 mL, mismatch ratio ≥1.8, and absolute mismatch volume ≥15 mL. Spearman correlation analysis and receiver operating characteristic curve analyses were performed. RESULTS: The median NCCT ASPECTS of the 164 patients was 8 (IQR 6-9), median sCTA-CS was 2 (IQR 1-2), and median CTP core volume was 8 mL (IQR 0-29.5). There was a strong correlation between NCCT ASPECTS and CTP core volume (rs=-0.756, p<0.0001) and a moderate correlation between the sCTA-CS and CTP core volume (rs=-0.450, p<0.0001). Integrating NCCT ASPECTS and sCTA-CS provided a higher area under the curve (AUC) for predicting target mismatch (AUC=0.882; sensitivity, 89.1%; specificity, 77.8%; p<0.001). CONCLUSIONS: NCCT ASPECTS had a strong correlation with CTP core volumes in patients with LVO-AIS in delayed time windows. Combining NCCT ASPECTS with sCTA-CS resulted in a more accurate prediction of target mismatch. If a CTP scan is not available, NCCT ASPECTS combined with sCTA-CS may guide clinicians in making treatment decisions.

A nomogram for predicting thrombus composition in stroke patients with large vessel occlusion: combination of thrombus density and perviousness with clinical features.

PURPOSE: To establish a nomogram incorporating pretreatment imaging parameters and clinical characteristics for predicting the thrombus composition of acute ischemic stroke (AIS) with large vessel occlusion (LVO). METHODS: We retrospectively enrolled patients with occlusion of the Middle Cerebral Artery (MCA) who underwent Mechanical Thrombectomy (MT). Retrieved thrombi were stained with Hematoxylin and Eosin (H&E) and Martius Scarlet Blue (MSB). Thrombi are assigned to the Fibrin-rich or RBC-rich group based on the relative fractions of Red Blood Cells (RBC), fibrin, and platelet. The independent risk factors for Fibrin-rich clots were determined via univariate and multivariate logistic regression analysis and were then integrated to establish a nomogram. RESULTS: In total, 98 patients were included in this study. Patients with fibrin-rich clots had worse functional outcome [modified Rankin scale (mRS) 0-2, 34.7% vs 63.2%, p = 0.005], longer procedure time (76.8 min vs 50.8 min, p = 0.001), and increased maneuvers of MT (1.84 vs 1.46, p = 0.703) than those with RBC-rich clots. The independent risk factors for Fibrin-rich clots were lower perviousness measured by Non-Contrast Computer Tomography (NCCT) and CT Angiography (CTA), lower thrombus relative attenuation on NCCT, elevated Platelet-WBC ratio (PWR) of admission peripheral blood, and previous antithrombotic medication. The nomogram showed good discrimination with an area under the Receiver Operating Characteristic (ROC) curve (AUC) of 0.852 (95% CI: 0.778-0.926). The calibration curve and decision curve analysis also displayed satisfactory accuracy and clinical utility. CONCLUSION: This study has developed and internally validated an easy-to-use nomogram which can help predict clot composition and optimize therapeutic strategies for thrombectomy.

Tmax profile in computed tomography perfusion-based RAPID software maps influences outcome after mechanical thrombectomy in patients with basilar artery occlusion.

BACKGROUND: Computed tomography perfusion (CTP) parameters have been shown to have predictive value for functional outcomes of patients with basilar artery occlusion (BAO). We report the predictive value of CTP-based software (CTP-Rapid Processing of Perfusion and Diffusion (RAPID); iSchemia View) for functional outcomes of patients with BAO after endovascular therapy (EVT). METHODS: Patients with BAO who underwent EVT were retrospectively analyzed in our center from December 2019 to July 2021. Baseline characteristics and imaging parameters from non-contrast CT, CT angiography (CTA), and CTP-RAPID were collected for analysis. RESULTS: Among the 55 patients enrolled in this study, 22 (40.0%) achieved a good functional outcome (modified Rankin Scale score ≤3 at 90 days). In the univariate analysis, posterior circulation Alberta Stroke Program Early CT Score, Basilar Artery on CT Angiography score, posterior circulation CTA score, posterior communicating artery deficiency, perfusion deficit volume in time to maximum (Tmax) >4 s, Tmax >6 s, and mismatch volume were associated with functional outcomes (all p<0.05). In the multivariate analysis, perfusion deficit volume in Tmax >6 s (OR 1.011 (95% CI 1.001 to 1.020)) and posterior circulation CTA score (OR 0.435 (95% CI 0.225 to 0.840)) remained independent outcome predictors (all p<0.05). CONCLUSIONS: Perfusion deficit volume in Tmax >6 s on CTP-RAPID imaging maps and basilar artery on CTA score have potential as functional outcome predictors in patients with BAO after EVT.

Early plasma D-dimer as a predictor of acute intracranial atherosclerosis-related large vessel occlusion in acute ischemic stroke.

BACKGROUND: Intracranial atherosclerosis-related large vessel occlusion (ICAS+LVO) poses an important technical challenge for endovascular thrombectomy (EVT). PURPOSE: To evaluate the value of D-dimer in predicting ICAS+LVO alone and in combination with other clinical and imaging predictors. MATERIAL AND METHODS: Consecutive patients who underwent EVT at our center between January 2018 and June 2021 were retrospectively reviewed. Patients were classified to the ICAS+LVO or ICAS-LVO group according to angiographic findings. Collateral gradings were evaluated based on computed tomography angiography and categorized as follows: score 0-1 unfavorable collaterals and score 2-3 favorable collaterals. Receiver operating characteristic curve was analyzed to evaluate the predictive value of D-dimer and the combination of other predictors for ICAS+LVO. RESULTS: A total of 374 patients were enrolled, among them, 107 (28.6%) had an ICAS+LVO, while ICAS-LVO was determined in 267 (71.4%) patients. Median D-dimer levels were lower (0.36 vs. 1.18 mg/L; P < 0.001) while the proportion of favorable collaterals was higher (85.0% vs. 22.5%; P < 0.001) in the ICAS+LVO group than the ICAS-LVO group. After multivariable analysis, D-dimer (adjusted odds ratio [OR]=0.32, 95% confidence interval [CI]=0.21-0.50; P < 0.001) and collaterals (adjusted OR=16.25, 95% CI=7.58-34.84; P < 0.001) remained independent predictors of ICAS+LVO. The area under the curve of D-dimer, collaterals, and combination for identification of ICAS+LVO was 0.82, 0.85, and 0.92, respectively. CONCLUSION: Low early plasma D-dimer levels are a significant and independent predictor of ICAS+LVO, and predictive value strengthens when in a combined model using D-dimer and collateral grading.

CT perfusion with increased temporal sampling interval to predict target mismatch status in patients with acute ischemic stroke.

PURPOSE: To evaluate the feasibility of using CT perfusion (CTP) with increased temporal sampling interval to predict the target mismatch status in acute ischemic stroke (AIS) patients with anterior circular large-vessel occlusion (LVO). METHODS: CTP with a sampling interval of 1.7 s (CTP1.7 s) was scanned in 77 AIS patients for pre-treatment evaluation. Simulated CTP data with sampling interval of 3.4 s (CTP3.4 s) or 5.1 s (CTP5.1 s) were reconstructed, respectively. Target mismatch was defined according to the EXTEND-IA (Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial) and DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke) trial criteria, respectively. Pearson correlation analysis, Mann-Whitney U test, Bland-Altman analysis, and chi-square test were used for statistical analysis as appropriate. RESULTS: Significant correlations were found on the volume of ischemic core, hypo-perfused area, mismatch area, and ratio between CTP1.7 s and CTP3.4 s or CTP5.1 s (all p < 0.001). There was no significant difference on the volume of ischemic core, hypo-perfused area, mismatch area, and mismatch ratio between CTP1.7 s and CTP3.4 s or CTP5.1 s (all p > 0.05). Compared with CTP1.7 s, CTP3.4 s or CTP5.1 s showed comparable performance in predicting the target mismatch status in the AIS patients with LVO (both p > 0.05). CONCLUSIONS: CTPs with increased temporal sampling intervals that lead to reduced radiation doses are feasible and may provide comparable performance in predicting target mismatch status in AIS patients with LVO.