ABSTRACT
Objective:To explore the value of the Wilcoxon-Mann-Whitney generalized dominance ratio (T max-weighted ratio) based on residual tissue time to peak (T max) delayed severity weighting in predicting the moderate to severe edema after acute anterior circulation ischemic stroke. Methods:The clinical and imaging features of patients with acute anterior circulation ischemic stroke from January 2019 to April 2022 in Yidu Central Hospital of Weifang were retrospectively analyzed. A total of 85 patients were enrolled, including 60 males and 25 females, with the age from 34 to 93 (67±11) years old. Patients underwent non-contrast CT, CT angiography of the head and neck, and CT perfusion imaging of the head, and ischemic core volume and the ratio of T max 4-6 s volume, T max 6-8 s volume, T max 8-10 s volume, and T max >10 s volume relative to the entire hypo-perfused area (T max>4 s volume) was measured, and the T max-weighted ratio was calculated, the collateral circulation were assessed. Patients were divided into mild edema group and moderate to severe edema group according to whether local swelling exceeded 1/3 of the unilateral cerebral hemisphere on non-contrast CT at 24-48 h. The indicators were compared between the two groups by independant t test, Mann-Whitney U and χ 2 test. The performance to predict moderate to severe edema was assessed using the receiver operating characteristic (ROC) curve. The univariate and multivariate logistic regression was used to analyze the risk factors for the moderate to severe edema. Differences in baseline National Institutes of Health Stroke Scale (NIHSS) score and infarct core volume were equalized by 1∶1 propensity score matching (PSM) and the differences of T max-weighted ratio between the two groups were further compared. Results:There were 52 cases in the mild edema group and 33 cases in the moderate to severe edema group. Baseline NIHSS score, T max>10 s volume, ischemic core volume, T max-weighted ratio and proportion of poor collateral circulation were higher in the moderate-severe edema group than those in the mild edema group ( P<0.001), T max 4-6 s volume was lower than in the mild edema group ( P<0.001). ROC analysis showed that the area under the curve (AUC) of T max-weighted ratio for predicting the incidence of moderate to severe edema was 0.885 (95%CI 0.798-0.944), with an optimal cut-off value of 1.17, sensitivity of 84.85% and specificity of 82.69% before PSM. The predictive ability based on T max-weighted ratio was similar to ischemic core volume( Z=0.64, P=0.520), T max 4-6 s volume ( Z=1.48, P=0.140) and superior to T max 6-8 s volume( Z=5.65, P<0.001), T max 8-10 s volume( Z=4.46, P<0.001), T max >10 s volume ( Z=2.91, P=0.004). Multivariate logistic regression analysis showed that T max-weighted ratio>1.17 was an independent predictor of the development of moderate to severe edema (OR=10.40,95%CI 2.65-40.83, P=0.001) through adjusted for baseline NIHSS score and ischemic core volume. After PSM, 14 patients in each group were included; the T max-weighted ratio was higher in the moderate-to-severe edema group than that in the mild edema group ( P<0.001), and the differences in other factors were not statistically significant (all P>0.05); ROC analysis showed that the AUC of T max-weighted ratio to predict the occurrence of moderate-to-severe edema was 0.852 (95%CI 0.667-0.957). Conclusion:The T max-weighted ratio can predict the occurrence of moderate-to-severe edema in brain tissue after acute anterior circulation ischemic stroke.
ABSTRACT
Objective:To explore the value of nomogram based on dual-energy CT (DECT) enhanced imaging in predicting postoperative recurrence-free survival (RFS) of early-stage glottic carcinoma (EGC).Methods:The clinicopathological and DECT data of patients with EGC confirmed by pathology in the Tianjin First Central Hospital from January 2015 to July 2018 were analyzed retrospectively. A total of 178 patients were enrolled, including 162 males and 16 females, with the age from 44 to 86 (62±9) years old. According to the follow-up data, the patients were divided into recurrent group ( n=32) and non-recurrent group ( n=146). The differences of clinicopathological data and DECT iodine maps parameters between the two groups were analyzed using χ 2 test, independent-sample t test and Mann-Whitney U test. The survival related cut-off values of the quantitative data between the two groups were selected by X-tile software. The survival curve was drawn using Kaplan-Meier method, and the difference of survival rate was tested with log-rank analysis. The variables with statistical differences were included in the Cox proportional hazard model for multivariate analysis to select the independent predictors of postoperative RFS. Based on the multivariate Cox analysis, the nomogram was drawn to predict the RFS at 1, 2 and 5 years. The prediction efficiency and clinical benefit of the nomogram were evaluated by C-index, calibration curve and decision curve analysis. Results:The median follow-up time was 24.3 months, ranging from 2 to 63 months. There was a significant difference in T-stage between recurrent and non-recurrent groups (χ2=9.21, P=0.002). The prognostic cutoff values obtained by X-tile software were arterial phase standardized iodine concentration (SIC AP)=0.28 and venous phase standardized iodine concentration (SIC VP)=0.87. The results of log-rank test showed that there were significant differences in RFS among patients with different T-stage, SIC AP and SIC VP (χ2=10.74, 15.50, 17.97, P=0.001,<0.001,<0.001). T-stage, SIC AP and SIC VP were identified as independent predictors of postoperative RFS (hazard ratio=2.271, 3.552, 3.266, P=0.026,<0.001, 0.003). The C-index of the nomogram combined with DECT parameter and T-stage was 0.785, which was higher than that of T-stage alone (0.622). The calibration curve showed that there was good consistency between the actual and predicted probability of the sample. The decision curve analysis showed that the clinical benefit of the nomogram was higher than that of the T-stage alone. Conclusion:The nomogram based on preoperative clinical factors (T-stage) and DECT iodine map factors (SIC AP and SIC vp) can predict the postoperative RFS of patients with EGC.