Comparative study of DSC-PWI and 3D-ASL in ischemic stroke patients / 华中科技大学学报（医学）（英德文版）

The purpose of this study was to quantitatively analyze the relationship between three dimensional arterial spin labeling (3D-ASL) and dynamic susceptibility contrast-enhanced perfusion weighted imaging (DSC-PWI) in ischemic stroke patients. Thirty patients with ischemic stroke were included in this study. All subjects underwent routine magnetic resonance imaging scanning, diffusion weighted imaging (DWI), magnetic resonance angiography (MRA), 3D-ASL and DSC-PWI on a 3.0T MR scanner. Regions of interest (ROIs) were drawn on the cerebral blood flow (CBF) maps (derived from ASL) and multi-parametric DSC perfusion maps, and then, the absolute and relative values of ASL-CBF, DSC-derived CBF, and DSC-derived mean transit time (MTT) were calculated. The relationships between ASL and DSC parameters were analyzed using Pearson's correlation analysis. Receiver operative characteristic (ROC) curves were performed to define the thresholds of relative value of ASL-CBF (rASL) that could best predict DSC-CBF reduction and MTT prolongation. Relative ASL better correlated with CBF and MTT in the anterior circulation with the Pearson correlation coefficients (R) values being 0.611 (P<0.001) and-0.610 (P<0.001) respectively. ROC curves demonstrated that when rASL ≤0.585, the sensitivity, specificity and accuracy for predicting ROIs with rCBF<0.9 were 92.3%, 63.6% and 76.6% respectively. When rASL ≤0.952, the sensitivity, specificity and accuracy for predicting ROIs rMTT>1.0 were 75.7%, 89.2% and 87.8% respectively. ASL-CBF map has better linear correlations with DSC-derived parameters (DSC-CBF and MTT) in anterior circulation in ischemic stroke patients. Additionally, when rASL is lower than 0.585, it could predict DSC-CBF decrease with moderate accuracy. If rASL values range from 0.585 to 0.952, we just speculate the prolonged MTT.

Serum matrix metalloproteinase-2 and tissue metalloproteinase inhibitor-2 are closely related to carotid atherosclerosis plaque vulnerability / 中华神经医学杂志

Objective To explore the correlation of serum matrix metalloproteinase-2 (MMP-2) and tissue metalloproteinase inhibitor-2 (TIMP-2) levels to carotid atherosclerosis plaque vulnerability in patients with anterior circulation infarction. Methods Sixty patients with anterior circulation infarction and 38 healthy volunteers were enrolled in this study. Color Doppler ultrasonography of the carotid artery was performed to determine the carotid intima-media thickness (IMT), Crouse plaque integral (CPI) score, and the total carotid plaque area (CPA). According to the nature of the carotid atherosclerosis plaque defined by ultrasonography, the patients were divided into vulnerable plaque (VP) group (33 cases), stable plaque (SP) group (27 cases), and no plaque (NP) group (38 cases). Serum MMP-2 and TIMP-2 levels were detected in these subjects using enzyme-linked immnosorbent assay (ELISA). Results Ultrasonography showed significantly greater/MT, CPI and CPA in VP group than in SP and NP groups (P<0.05). Serum MMP-2 level was significantly elevated in VP group as compared with that in SP and NP groups (P<0.05). Serum TIMP-2 level was significantly lower in VP group than in SP and NP groups (P<0.05). In VP group, serum MMP-2 level and MMP-2/TIMP-2 ratio were found to positively correlate to IMT, CPl and CPA (r=0.961, 0.966, and 0.804 for MMP-2, respectively, P<0.05;r=0.625, 0.709, and 0.651 for MMP-2/TIMP-2 ratio, respectively, P<0.05), while TIMP-2 was inversely correlated to IMT, CPI and CPA (r=-0.944, -0.996, and -0.859, respectively, P<0.05). Conclusion Serum MMP-2 and TIMP-2 levels and MMP-2/TIMP-2 ratio are closely correlated to carotid atherosclerosis plaque vulnerability.