title: The Role of Dynamic Contrast-Enhanced MR in Evaluating Level III Collateral Circulation in a Rat Model of Acute Ischemic Stroke.
abstract: The study aimed to investigate the correlations between parameters of permeability magnetic resonance (MR) and the intensity of vasculature in the focal ischemic cortex of a rat model of middle cerebral artery occlusion. In the present study, sham operation or ischemic-reperfusion with tissue plasminogen activator (tPA) thrombolysis were performed in rats. Cranial MR scans and brain tissue samples were obtained from all animals. Brain slices were stained for immunohistological analyses with confocal fluorescence microscopy, and the intensities of microvessels and capillaries were calculated. Consistency between collateral circulation imaging classification and pathological vascular density was analyzed. We found that the Ktransvalue and capillary intensity have the similar trends of declining and increasing, according to different time points, if compared with the sham operation group (P < 0.05). Permeability parameters have better correlations with capillary intensity, and Ktransvalue had the best correlation at 4.5 h (kappa = 0.764, P < 0.001), while injection area under curve (IAUC) at 7 days (kappa = 0.725, P < 0.001). Susceptibility-weighted imaging (SWI) exhibited better correlation with microvessel intensity at both 3 days (kappa = 0.715, P < 0.001) and 7 days (kappa = 0.719, P < 0.001). In conclusion, the permeability parameters, such as IAUC and Ktransmap, can quantitatively assess capillary intensity, which may indicate angiogenesis categorized as level III collateral circulation after ischemic stroke.
authors.affiliation: Department of Neurology, Military General Hospital of Beijing PLA, Beijing, 100700, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Neurology, Military General Hospital of Beijing PLA, Beijing, 100700, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Neurology, Military General Hospital of Beijing PLA, Beijing, 100700, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Radiology, Military General Hospital of Beijing PLA, Beijing, 100700, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Wu
authors.affiliation: GE Healthcare, Beijing, China.
authors.forename: Zihua
authors.initials: Z
authors.lastname: Su
authors.affiliation: Department of Neurology, Military General Hospital of Beijing PLA, Beijing, 100700, China. zhugmdc@aliyun.com.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Department of Neurology, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China. hujuncq@163.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Hu
mesh_terms: D000818:Animals; D002196:Capillaries / Q000473:pathology / Q000503:physiopathology; D003097:Collateral Circulation / Q000502:physiology*; D003287:Contrast Media / Q000737:chemistry*; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D007091:Image Processing, Computer-Assisted; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D017207:Rats, Sprague-Dawley; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology*
chemical_list: D003287:Contrast Media
keywords: Collateral circulation; Dynamic contrast-enhanced MR; Permeability; Stroke