title: Magnetic resonance angiography detection of abnormal carotid artery plaque in patients with cryptogenic stroke.
abstract: BACKGROUND
  Magnetic resonance imaging of carotid plaque can aid in stroke risk stratification in patients with carotid stenosis. However, the prevalence of complicated carotid plaque in patients with cryptogenic stroke is uncertain, especially as assessed by plaque imaging techniques routinely included in acute stroke magnetic resonance imaging protocols. We assessed whether the magnetic resonance angiography-defined presence of intraplaque high-intensity signal (IHIS), a marker of intraplaque hemorrhage, is associated with ipsilateral cryptogenic stroke.
  
  
  RESULTS
  Cryptogenic stroke patients with magnetic resonance imaging evidence of unilateral anterior circulation infarction and without hemodynamically significant (≥50%) stenosis of the cervical carotid artery were identified from a prospective stroke registry at a tertiary-care hospital. High-risk plaque was assessed by evaluating for IHIS on routine magnetic resonance angiography source images using a validated technique. To compare the presence of IHIS on the ipsilateral versus contralateral side within individual patients, we used McNemar's test for correlated proportions. A total of 54 carotid arteries in 27 unique patients were included. A total of 6 patients (22.2%) had IHIS-positive nonstenosing carotid plaque ipsilateral to the side of ischemic stroke compared to 0 patients who had IHIS-positive carotid plaques contralateral to the side of stroke (P=0.01). Stroke severity measures, diagnostic evaluations, and prevalence of vascular risk factors were not different between the IHIS-positive and IHIS-negative groups.
  
  
  CONCLUSIONS
  Our findings suggest that a proportion of strokes classified as cryptogenic may be mechanistically related to complicated, nonhemodynamically significant cervical carotid artery plaque that can easily be detected by routine magnetic resonance imaging/magnetic resonance angiography acute stroke protocols.
authors.affiliation: Department of Radiology, Weill Cornell Medical College (WCMC), New York, NY (A.G., H.B.) Feil Family Brain and Mind Research Institute, Weill Cornell Medical College (WCMC), New York, NY (A.G., G.G., B.B.N., C.I., H.K.).
authors.forename: Ajay
authors.initials: A
authors.lastname: Gupta
authors.affiliation: Feil Family Brain and Mind Research Institute, Weill Cornell Medical College (WCMC), New York, NY (A.G., G.G., B.B.N., C.I., H.K.).
authors.forename: Gino
authors.initials: G
authors.lastname: Gialdini
authors.affiliation: Department of Neurology, Weill Cornell Medical College (WCMC), New York, NY (M.P.L., B.B.N., C.I., H.K.).
authors.forename: Michael P
authors.initials: MP
authors.lastname: Lerario
authors.affiliation: Department of Radiology, Weill Cornell Medical College (WCMC), New York, NY (A.G., H.B.).
authors.forename: Hediyeh
authors.initials: H
authors.lastname: Baradaran
authors.affiliation: Department of Healthcare Policy and Research, Weill Cornell Medical College (WCMC), New York, NY (A.G.).
authors.forename: Ashley
authors.initials: A
authors.lastname: Giambrone
authors.affiliation: Department of Neurology, Weill Cornell Medical College (WCMC), New York, NY (M.P.L., B.B.N., C.I., H.K.) Feil Family Brain and Mind Research Institute, Weill Cornell Medical College (WCMC), New York, NY (A.G., G.G., B.B.N., C.I., H.K.).
authors.forename: Babak B
authors.initials: BB
authors.lastname: Navi
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, NY (R.S.M.).
authors.forename: Randolph S
authors.initials: RS
authors.lastname: Marshall
authors.affiliation: Department of Neurology, Weill Cornell Medical College (WCMC), New York, NY (M.P.L., B.B.N., C.I., H.K.) Feil Family Brain and Mind Research Institute, Weill Cornell Medical College (WCMC), New York, NY (A.G., G.G., B.B.N., C.I., H.K.).
authors.forename: Costantino
authors.initials: C
authors.lastname: Iadecola
authors.affiliation: Department of Neurology, Weill Cornell Medical College (WCMC), New York, NY (M.P.L., B.B.N., C.I., H.K.) Feil Family Brain and Mind Research Institute, Weill Cornell Medical College (WCMC), New York, NY (A.G., G.G., B.B.N., C.I., H.K.).
authors.forename: Hooman
authors.initials: H
authors.lastname: Kamel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000473:pathology; D016893:Carotid Stenosis / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D020521:Stroke / Q000209:etiology*
keywords: carotid artery; cryptogenic stroke; magnetic resonance angiography; magnetic resonance imaging; risk factor; stroke