Objective:To develop a nomogram model based on clinical and imaging parameters to predict the etiological type of acute ischemic stroke (AIS).Methods:Patients with AIS received endovascular treatment in Beijing Hospital from March 2016 to December 2021 were retrospectively included. According to the etiological type, they were divided into large artery atherosclerosis (LAA) and cardioembolism (CE). The clinical and imaging parameters mostly relevant to the etiological type were selected by LASSO regression, and a nomogram model for predicting the etiological type of AIS was established by multifactorial logistic regression to investigate the predictive value of relevant clinical imaging parameters. In addition, the diagnostic efficacy of the prediction model was assessed by receiver operator characteristic (ROC) curves, calibration curves, and clinical decision curves. Results:A total of 136 AIS patients with anterior circulation large vessel occlusion received endovascular treatment were included, including 62 patients with CE (45.6%) and 74 with LAA (54.4%). Variables with P<0.10 in the univariate analysis were included in LASSO regression to screen for relevant variables. The gender, baseline National Institute of Health Stroke Scale (NIHSS) score, penumbra to ischemic core ratio, brain natriuretic peptide (BNP), and platelet (PLT) count were included into the multivariate logistic regression model. The results revealed that gender (odds ratio [ OR] 2.632, 95% confidence interval [ CI] 1.048-6.607; P=0.039), baseline NIHSS score ( OR 1.078, 95% CI 1.002-1.160; P=0.043), BNP ( OR 1.004, 95% CI 1.002-1.007. P<0.001), PLT ( OR 0.991, 95% CI 0.982-0.999; P=0.031) as the predictors to distinguish LAA from CE. In addition, the penumbra to infarct core ratio ( OR 0.886, 95% CI 0.785-1.000; P=0.050) also played an important role in predicting the model. The diagnostic efficacy of this predictive model was analyzed by the ROC curves, with an area under the curve of 0.881 (95% CI 0.815-0.930, P<0.001). Bootstrap internal validation showed that the good compliance with a mean absolute error of 0.027 for true versus predicted value compliance. Calibration curves, clinical decision curves, and Hosmer-Lemeshow test ( P=0.562) showed good agreement between the predicted and actual values of the model. Conclusion:Patients with CE are more common in women, have higher NIHSS scores and BNP, and have lower PLT and penumbra to ischemic core ratio. The nomogram model combining the above indicators can better identify LAA and CE, and maybe helpful in clinical decision making.

Objective:To investigate the risk factors of infarct growth rate of elderly acute ischemic stroke(AIS)patients with endovascular treatment(EVT)and its influence on prognosis.Methods:Elderly AIS patients who underwent EVT at Beijing hospital from June 2016 to October 2020 were retrospectively included.Infarct growth rate(ml/h)=infarct core volume(ml)/time from stroke onset to CTP examination(h).Based on the rate of infarct growth and the patient's clinical severity, ROC curve was established, and the cut-off value of the ROC curve was obtained.By the cut-off value of the rate of infarct growth, the patients were divided into cerebral infarct slow-growth group and rapid-growth group.Predictors of rapid growth in infarct were analyzed by univariate and multivariate analysis.The patients were divided into good prognosis group(mRS score 0-2)and poor prognosis group(mRS score 3-6)according to the mRS score at the day 90 and the predictors of poor prognosis were analyzed separately.Results:A total of 67 elderly AIS patients were included with age ranging from 65-96 years and an average of(78.8±7.6)years.(1)The cut-off value of the optimal infarct growth rate for patients with good and poor prognosis was 8.89 ml/h.The patients were divided into fast-growth group(26 patients)and slow-growth group(41 patients)according the cut-off value.(2)Multivariate logistic regression showed that only poor collateral circulation was an independent predictor for fast infarct growth( OR=0.162, 95% CI: 0.053-0.489).(3)Faster infarct growth rate( OR=1.173, 95% CI: 1.044-1.318)and high NIHSS score( OR=1.146, 95% CI: 1.018-1.291)were predictors of poor prognosis. Conclusions:Collateral circulation status is a major influencing factor for the infarct growth rate, and a faster infarct growth rate is a predictor of poor prognosis for elderly AIS patients after endovascular treatment.

Objective:To assess the prognostic value of the collateral status and clot burden score based on four-dimensional computed tomography angiography(4D CTA)in anteriorcir culation is chemics troke patients with large ischemic core after endovascular treatment.Methods:Clinical and imaging data of 36 anterior circulation ischemic stroke patients with large infarct core (infarct core≥50.0 ml) after endovascular treatment at our institution from March 2016 to September 2020 were retrospectively reviewed. According to the modified Rankin Scale (mRS) score, patients were divided into the good outcome (mRS score 0-2) and poor outcome (mRS score 3-6) groups. Mann-Whitney U and Fisher tests were used to compare the 4D CTA collateral circulation score, clot burden score, and baseline clinical data between the good and poor outcome groups. Multivariate logistic regression was used to analyze the risk factors associated with the poor outcome (mRS score 3-6) and mortality in patients with large infarct core stroke. Finally, based on the 90-day outcome, a ROC curve was used to obtain the cut-off values for poor prognosis (mRS 3-6) and death, respectively. Results:Ten patients (27.8%) had good outcome and 26 (72.2%) had poor outcome. The patients in the poor outcome group had older median age, higher blood glucose, lower 4D CTA collateral circulation score, lower clot burden score, larger infarct core volume, and higher hemorrhagic transformation and brain hernia (all P<0.05). Multivariate logistic regression showed that the poor collateral circulation score on 4D CTA( OR=0.18, 95% CI: 0.03-0.99, P<0.05)and clot burden score( OR=0.64, 95% CI: 0.44-0.93, P<0.05) were independent predictors of the poor prognosis. The ROC curves revealed that the cut-off value of infarct core for distinguishing between good prognosis and poor prognosis was 63.7 ml, while that for distinguishing between survival and death was 130.3 ml. Conclusions:Endovascular treatment may improve the prognosis of patients with large infarct core of anterior circulation is chemic stroke if the patients have good 4D CTA collateral circulation score and high clot burden score.

Objective:To explore the significance of four-dimensional CT angiography(4D CTA) and CT perfusion (CTP) imaging in evaluating collateral circulation grades in patients with moyamoya disease and moyamoya syndrome and their relationship with cerebral hemodynamics.Methods:The clinical and imaging data of 32 patients with moyamoya disease and moyamoya syndrome in Beijing Hospital from January 2017 to January 2022 were retrospectively analyzed. All patients underwent 4D CTA-CTP imaging. Collateral circulation was scored on CTA images by using Alberta stroke program early CT score system, and on digital subtraction angiography (DSA) images by using American society of interventional and therapeutic neuroradiology/Society of interventional radiology score system, respectively. The patients were divided into Ⅰ-Ⅲ circulation compensation grades based on collateral circulation score. Regions of interest were delineated at basal ganglia on perfusion maps and the perfusion parameters were obtained including cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), mean transit time (TTP) and delay time (DLY). The Kruskal-Wallis test was used to compare the perfusion parameters in different collateral circulation grades, and pairwise comparison was performed with Bonferroni correction. Kappa and Spearman tests were used to analyze the consistency and correlation of 4D CTA and DSA in the classification of collateral circulation.Results:4D CTA and DSA had a moderate consistency (Kappa=0.693, P<0.001) and a strong correlation ( r=0.805, P<0.001) in evaluating collateral grades. There were statistically significant differences in CBF, MTT and TTP among collateral compensation grade Ⅰ, grade Ⅱ and grade Ⅲ ( H values were 7.91, 11.69, 8.93; P values were 0.019, 0.003 and 0.012, respectively). Further pairwise comparison showed that the CBF of collateral compensation grade Ⅰ was lower than that of grade Ⅲ ( P=0.015), MTT of grade Ⅱ was higher than that of grade Ⅲ ( P=0.005), and TTP of grade Ⅰ was higher than that of grade Ⅲ ( P=0.015). There was no statistical significance of other indicators in pairwise comparison. There were no significant differences in CBV and DLY among collateral compensation grade Ⅰ, grade Ⅱ and grade Ⅲ ( P>0.05). Conclusions:4D CTA-CTP is equivalent to DSA in evaluating collateral circulation in patients with moyamoya disease and moyamoya syndrome. It can also evaluate the cerebral hemodynamics comprehensively, which has high clinical significance for disease monitoring.