title: Susceptible vessel sign: identification of arterial occlusion and clinical implications in acute ischaemic stroke.
abstract: OBJECTIVE
  To determine the accuracy of the susceptible vessel sign (SVS) in the detection of arterial occlusion and its clinical implication in acute ischaemic stroke.
  
  
  METHODS
  Consecutive ischaemic stroke patients who underwent magnetic resonance imaging (MRI) with susceptibility-weighted imaging (SWI) within 24 hours of symptom onset or time last-seen-well were included. Two independent neuroradiologists reviewed the SWI for evidence of the SVS. Admission stroke severity was determined by the National Institute of Health Stroke Scale (NIHSS) scores, and poor clinical outcome was defined by a 3-months modified Rankin scale (mRS) score >2.
  
  
  RESULTS
  The SVS was identified in 26 (12%) of 213 patients with substantial inter-reviewer agreement. The SVS had 99% specificity, 88% negative predictive value (NPV), 51% sensitivity, and 92% positive predictive value (PPV) for detection of acute arterial occlusions. In consecutive stroke patients, the presence of SVS was associated with higher admission NIHSS scores (median 9 versus 3, p<0.001), arterial occlusion (92% versus 12%, p<0.001), larger infarct volume (162±180 ml versus 25±48 ml, p=0.001), and higher rate of poor clinical outcome at 3-months follow-up (58% versus 25%, p=0.001). In the subset of patients with acute arterial occlusion (n=47), the SVS was associated with higher admission NIHSS scores (median of 10 versus 3, p=0.038) and larger infarct volumes (173±184 ml versus 76±112 ml, p=0.034).
  
  
  CONCLUSIONS
  The SVS is a highly specific sign of occlusive arterial thrombus, and is associated with larger infarct volume and more severe presentation in a series of consecutive stroke patients, as well as in the subgroup of patients with acute arterial occlusion.
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: S
authors.initials: S
authors.lastname: Payabvash
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Benson
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: S
authors.initials: S
authors.lastname: Taleb
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Rykken
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA; Department of Radiology, Hennepin County Medical Center, Minneapolis, MN, USA.
authors.forename: B
authors.initials: B
authors.lastname: Hoffman
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA; Department of Radiology, Hennepin County Medical Center, Minneapolis, MN, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: McKinney
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA; Department of Radiology, Hennepin County Medical Center, Minneapolis, MN, USA. Electronic address: mark.oswood@hcmed.org.
authors.forename: M C
authors.initials: MC
authors.lastname: Oswood
mesh_terms: D015897:Comorbidity; D004198:Disease Susceptibility / Q000000981:diagnostic imaging / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D020767:Intracranial Thrombosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D018810:Magnetic Resonance Angiography / Q000379:methods / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D011379:Prognosis; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D020521:Stroke / Q000000981:diagnostic imaging* / Q000453:epidemiology*