title: Vessel size imaging reveals pathological changes of microvessel density and size in acute ischemia.
abstract: The aim of this study was to test the feasibility of vessel size imaging with precise evaluation of apparent diffusion coefficient and cerebral blood volume and to apply this novel technique in acute stroke patients within a pilot group to observe the microvascular responses in acute ischemic tissue. Microvessel density-related quantity Q and mean vessel size index (VSI) were assessed in 9 healthy volunteers and 13 acute stroke patients with vessel occlusion within 6 hours after symptom onset. Our results in healthy volunteers matched with general anatomical observations. Given the limitation of a small patient cohort, the median VSI in the ischemic area was higher than that in the mirrored region in the contralateral hemisphere (P<0.05). Decreased Q was observed in the ischemic region in 2 patients, whereas no obvious changes of Q were found in the remaining 11 patients. In a patient without recanalization, the VSI hyperintensity in the subcortical area matched well with the final infarct. These data reveal that different observations of microvascular response in the acute ischemic tissue seem to emerge and vessel size imaging may provide useful information for the definition of ischemic penumbra and have an impact on future therapeutic approaches.
authors.affiliation: Center for Stroke Research Berlin (CSB), Charité-Universitätsmedizin Berlin, Berlin, Germany. chao.xu@charite.de
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
authors.forename: Wolf U H
authors.initials: WU
authors.lastname: Schmidt
authors.forename: Kersten
authors.initials: K
authors.lastname: Villringer
authors.forename: Peter
authors.initials: P
authors.lastname: Brunecker
authors.forename: Valerij
authors.initials: V
authors.lastname: Kiselev
authors.forename: Peter
authors.initials: P
authors.lastname: Gall
authors.forename: Jochen B
authors.initials: JB
authors.lastname: Fiebach
mesh_terms: D000208:Acute Disease; D000328:Adult; D002545:Brain Ischemia / Q000097:blood*; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D055806:Microvessels / Q000473:pathology* / Q000503:physiopathology