title: Correlation of imaging and histopathology of thrombi in acute ischemic stroke with etiology and outcome: a systematic review.
abstract: OBJECTIVE
  Studying the imaging and histopathologic characteristics of thrombi in ischemic stroke could provide insights into stroke etiology and ideal treatment strategies. We conducted a systematic review of imaging and histologic characteristics of thrombi in acute ischemic stroke.
  
  
  METHODS
  We identified all studies published between January 2005 and December 2015 that reported findings related to histologic and/or imaging characteristics of thrombi in acute ischemic stroke secondary to large vessel occlusion. The five outcomes examined in this study were (1) association between histologic composition of thrombi and stroke etiology; (2) association between histologic composition of thrombi and angiographic outcomes; (3) association between thrombi imaging and histologic characteristics; (4) association between thrombi imaging characteristics and angiographic outcomes; and (5) association between imaging characteristics of thrombi and stroke etiology. A meta-analysis was performed using a random effects model.
  
  
  RESULTS
  There was no significant difference in the proportion of red blood cell (RBC)-rich thrombi between cardioembolic and large artery atherosclerosis etiologies (OR 1.62, 95% CI 0.1 to 28.0, p=0.63). Patients with a hyperdense artery sign had a higher odds of having RBC-rich thrombi than those without a hyperdense artery sign (OR 9.0, 95% CI 2.6 to 31.2, p<0.01). Patients with a good angiographic outcome had a mean thrombus Hounsfield unit (HU) of 55.1±3.1 compared with a mean HU of 48.4±1.9 for patients with a poor angiographic outcome (mean standard difference 6.5, 95% CI 2.7 to 10.2, p<0.001). There was no association between imaging characteristics and stroke etiology (OR 1.13, 95% CI 0.32 to 4.00, p=0.85).
  
  
  CONCLUSIONS
  The hyperdense artery sign is associated with RBC-rich thrombi and improved recanalization rates. However, there was no association between the histopathological characteristics of thrombi and stroke etiology and angiographic outcomes.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Waleed
authors.initials: W
authors.lastname: Brinjikji
authors.affiliation: Department of Engineering, Galway-Mayo Institute of Technology, Galway, Ireland.
authors.forename: Sharon
authors.initials: S
authors.lastname: Duffy
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Burrows
authors.affiliation: Department of Neurology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Hacke
authors.affiliation: Department of Neurology, University of California, Los Angeles, California, USA.
authors.forename: David
authors.initials: D
authors.lastname: Liebeskind
authors.affiliation: Department of Neurology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
authors.forename: Charles B L M
authors.initials: CBLM
authors.lastname: Majoie
authors.affiliation: Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Diederik W J
authors.identifier: http://orcid.org/0000-0002-9234-3515
authors.initials: DWJ
authors.lastname: Dippel
authors.affiliation: Department of Neurosurgery, University of Buffalo, Buffalo, New York, USA.
authors.forename: Adnan H
authors.initials: AH
authors.lastname: Siddiqui
authors.affiliation: Department of Neurology, University of Cincinatti, Cincinatti, Ohio, USA.
authors.forename: Pooja
authors.initials: P
authors.lastname: Khatri
authors.affiliation: Department of Radiology, University of Tennessee Medical Center, Chatanooga, Tennessee, USA.
authors.forename: Blaise
authors.initials: B
authors.lastname: Baxter
authors.affiliation: Department of Neurology, Emory University, Atlanta, Georgia, USA.
authors.forename: Raul
authors.initials: R
authors.lastname: Nogeuira
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts, Worcester, Massachusetts, USA.
authors.forename: Matt
authors.initials: M
authors.lastname: Gounis
authors.affiliation: Department of Neurology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Tudor
authors.initials: T
authors.lastname: Jovin
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: David F
authors.initials: DF
authors.lastname: Kallmes
mesh_terms: D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D003952:Diagnostic Imaging / Q000639:trends; D005260:Female; D006801:Humans; D008297:Male; D020521:Stroke / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D013927:Thrombosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D016896:Treatment Outcome
keywords: CT; Intervention; Stroke; Thrombectomy; Thrombolysis