title: Thrombus Characteristics Are Related to Collaterals and Angioarchitecture in Acute Stroke.
abstract: BACKGROUND
  We have theorized that clots with stasis are longer. We therefore explored the relationship between thrombus imaging characteristics on noncontrast computed tomography (NCCT) and magnetic resonance imaging (MRI) with clot length and pial collaterals on baseline computed tomography angiography (CTA).
  
  
  METHODS
  Prospective study of acute ischemic stroke patients (2005-2009) from Keimyung University. Patients with known stroke symptom onset time, baseline CTA, MRI, and with M1-Middle Cerebral Artery (MCA)±intracranial internal carotid artery (ICA) occlusions were included. Clot length and pial collaterals were measured on baseline CTA.
  
  
  RESULTS
  A total of 104 patients (mean age 65.1±12.28 years, 56.7% male, median baseline National Institutes of Health Stroke Scale 13) with intracranial ICA + MCA (n=50) or isolated M1-MCA (n=54) occlusions were included. Hyperdense sign on NCCT had a median clot length of 42.3 mm versus 29.5 mm when hyperdense negative (p=0.02). Clots showing blooming artifact on gradient recall echo MRI had a median length of 39.1 mm versus 24.5 mm without blooming (p=0.005). Patients with poor baseline collaterals on CTA had longer clots than those with intermediate/good collaterals (median clot length 49.4 mm vs 34.9 mm vs 20.5 mm respectively, p<0.001). In censored logistic regression modeling, clot length was an independent predictor of hyperdense sign (p=0.05) and of the presence of blooming artifact (p=0.006).
  
  
  CONCLUSIONS
  Clot length and baseline collateral status are independent predictors of clot hyperdensity on NCCT and blooming artifact on gradient recall echo. Longer clots are more likely to be hyperdense and to bloom more, probably because portions of these clots are freshly formed locally due to of stasis of blood around the original clot. This stasis could be because of poor collaterals and inefficient angio-architecture within the cerebral arterial tree.
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Emmad M
authors.initials: EM
authors.lastname: Qazi
authors.affiliation: 2Department of Neurology,Dongsan Medical Center,Keimyung University,Daegu,South Korea.
authors.forename: Sung Il
authors.initials: SI
authors.lastname: Sohn
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Sachin
authors.initials: S
authors.lastname: Mishra
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Mohammed A
authors.initials: MA
authors.lastname: Almekhlafi
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Muneer
authors.initials: M
authors.lastname: Eesa
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: d'Esterre
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Abdul A
authors.initials: AA
authors.lastname: Qazi
authors.affiliation: 5Department of Radiology,Girona Biomedical Research Institute,Diagnostic Imaging Institute,Girona,Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Puig
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Mayank
authors.initials: M
authors.lastname: Goyal
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
authors.affiliation: 1Calgary Stroke Program,Department of Clinical Neurosciences,Hotchkiss Brain Institute,University of Calgary,Canada.
authors.forename: Bijoy K
authors.initials: BK
authors.lastname: Menon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology*; D002533:Cerebral Angiography / Q000379:methods; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020521:Stroke / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D013927:Thrombosis / Q000000981:diagnostic imaging / Q000473:pathology*; D010959:Tissue Plasminogen Activator / Q000378:metabolism
chemical_list: D010959:Tissue Plasminogen Activator
keywords: Magnetic Resonance Imaging; stroke; stroke imaging