The Establishment And Clinical Application Of Evaluating Collateral Circulation Based On 4D CTA

(Part 1)Establishment of 4D CTA Collateral Circulation Scoring System and its Application Value in Prognostic Evaluation for Endovascular Treatment in Acute Ischemic Stroke Patients ObjectiveWe aim to use 4D CTA with a new comprehensive and objective scoring system to assess collateral circulation.Compare 4D CTA and single-phase CTA(s CTA)in assessing collateral circulation and explore the value of prognosis prediction in patients with endovascular treatments.MethodsPatients with unilateral anterior circulation large vessels occlusion from June2017 to July 2018 were reviewed in this study retrospectively.s CTA and 4D CTA acquired by CT perfusion scanning were analyzed for collateral circulation assessment.The collateral vessels were scored 0 to 3 based on s CTA: 0-1 point indicated poor collateral circulation;2-3 points indicated good collateral circulation.The collateral vessels were scored 0 to 4 according to modified collateral circulation scoring based on 4D CTA: 0-2 points indicated poor collateral circulation;3-4 points indicated good collateral circulation.Good prognosis was defined as modified Rankin scale(m RS)score of 0-2.The correlations of clinical prognosis and infarct volume with collateral status on 4D CTA and s CTA were analyzed.Inter-rater reliability was assessed by intraclass correlation coefficient(ICC).Univariate analysis was used to analyze the good prognosis group and the poor prognosis group,in order to find statistically significant independent variables.Logistic regression was used to analyze the relationship between collateral circulation and prognosis.ResultsA total of 34 patients with acute cerebral infarction who received unilateral anterior circulation vascular occlusion and received endovascular intervention were included.The average age was 71.1 ± 11.5 years.Among them,14(41.2%)had good prognosis and 20(58.8%)had poor prognosis.The collateral score on 4D CTA and s CTA were both negatively correlated with m RS scores(r = 0.692 and 0.379,respectively,P < 0.01)and the final infarction volume(r = 0.581 and 0.443,respectively,P ≤ 0.01).Univariate analysis of the good prognosis group and the poor prognosis group showed that there was statistically significant in baseline NIHSS score,baseline ASPECTS score,final infarct volume,and 4D CTA collateral circulation score(P < 0.05).Logistic regression analysis showed that collateral circulation on 4D CTA was an independent factor for predicting the prognosis(OR =0.101;95%CI: [0.101-0.924];P = 0.042),but there was no statistically significant difference in the s CTA collateral circulation score(P = 0.214).ROC curve results show that 4D CTA collateral circulation scoring had a good predicting efficacy on clinical prognosis(AUC = 0.936;95% CI: [0.751-0.992],P < 0.005).Patients with good collaterals(4D CTA scores of 3-4)obtained more benefit from endovascular treatment(P = 0.029)compared with patients with poor collaterals(P = 1.000).Conclusion4D CTA could be applied to effectively evaluate cerebral collateral status.The accurate assessment of collateral circulation based on 4D CTA would be helpful to make medical decisions,especially for those patients who would undergo endovascular interventional treatment.(Part 2)Predictors of Hemorrhage Transformation after Endovascular Treatments for Acute Ischemic Stroke: The Role of Collateral CirculationObjectiveAlthough the positive role of good collateral circulation on infarct volume and clinical outcome have been confirmed in previous studies,few studies have investigated the relationship between hemorrhage transformation and collateral circulation in acute ischemic stroke(AIS).This study aimed to assess whether collateral circulation is an essential factor of HT after endovascular treatments Methods71 consecutive AIS patients who underwent endovascular treatments between July 2015 and February 2019 were studied retrospectively.The correlations between HT with collateral vessels on 4D CT angiography(4D CTA)and with other predictive factors for hemorrhage transformation(e.g.National Institutes of Health Stroke Scale [NIHSS] score,age,sex,serum glucose,atrial fibrillation history,etc.)were evaluated by logistic regression analysis.ResultsThe rate of hemorrhage transformation was 42.3%(30/71)in AIS patients in this study.Multivariate logistic regression showed that good collateral status(OR 0.76,95% CI 0.73–0.80)was associated with lower risk of hemorrhage transformation.History of atrial fibrillation(OR 2.35,95% CI 1.96–2.82),baseline NIHSS scores(OR 2.00,95% CI 1.72–2.32),higher serum glucose level(OR 1.70,95% CI1.57–1.85)were independent risk factors of hemorrhage transformation.ConclusionsPatients with poor collateral circulation are at higher risk of hemorrhage transformation after endovascular therapies.Thus,variations of collateral circulation based on 4D CTA may be one of the important factors for personalized clinical treatments.Meanwhile,high blood glucose,atrial fibrillation and baseline NIHSS score are all important independent predictors of hemorrhage transformation.