title: High-Resolution Vessel Wall Magnetic Resonance Imaging in Angiogram-Negative Non-Perimesencephalic Subarachnoid Hemorrhage.
abstract: OBJECTIVE
  Standard magnetic resonance imaging (MRI) rarely identifies the cause of hemorrhage in patients with an angiogram-negative, non-perimesencephalic subarachnoid hemorrhage (SAH). Yet up to 10 % of these patients have recurrent hemorrhage. The aim of the study was to explore the potential role of high-resolution contrast-enhanced 3-Tesla vessel wall-MRI in patients with angiogram-negative SAH.
  
  
  METHODS
  We performed intracranial vessel wall-MRI of the circle of Willis using a 3-Tesla scanner in consecutive patients presenting with a spontaneous, angiogram-negative, non-perimesencephalic SAH. Vessel wall-MRI included T1-, T2-, and gadolinium-enhanced T1-weighted two-dimensional black-blood sequences in multiple planes (voxel size 0.4 × 0.4 × 2.0 mm). Two neuroradiologists independently scored abnormalities of the arterial wall.
  
  
  RESULTS
  In all, 11 patients (mean age 59 years) underwent vessel wall-MRI. A total of seven patients had vessel wall abnormalities despite normal catheter angiography. Two patients had focal abnormalities contiguous with the outer margin of the basilar artery wall for which we considered a differential of ruptured blood blister aneurysm, thrombosed aneurysm, and loculated extramural blood from elsewhere. Two patients had arterial wall enhancement involving multiple arteries, possibly secondary to SAH. Three patients had arterial wall enhancement at sites of dural penetration, remote from the SAH, likely related to age and atherosclerotic risk factors. Vessel wall-MRI did not alter patient management in this cohort.
  
  
  CONCLUSIONS
  Vessel wall-MRI showed abnormalities in seven patients with angiogram-negative SAH. These findings did not alter patient management, but the findings may be useful for other physicians who choose to perform vessel wall-MRI in this patient population.
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada.
authors.forename: J M
authors.initials: JM
authors.lastname: Coutinho
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada.
authors.forename: R H
authors.initials: RH
authors.lastname: Sacho
authors.affiliation: Division of Neurology, Department of Medicine, University Health Network and the University of Toronto, Toronto, ON, Canada.
authors.forename: J D
authors.initials: JD
authors.lastname: Schaafsma
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Agid
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada.
authors.forename: T
authors.initials: T
authors.lastname: Krings
authors.affiliation: Division of Neurosurgery, Department of Surgery, University Health Network and the University of Toronto, Toronto, ON, Canada.
authors.forename: I
authors.initials: I
authors.lastname: Radovanovic
authors.affiliation: Departments of Diagnostic Radiology and Neurosurgery, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: C C
authors.initials: CC
authors.lastname: Matouk
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada.
authors.forename: D J
authors.initials: DJ
authors.lastname: Mikulis
authors.affiliation: Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network and the University of Toronto, 399 Bathurst St, M5T 2S8, Toronto, ON, Canada. danny.mandell@uhn.ca.
authors.forename: D M
authors.initials: DM
authors.lastname: Mandell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography / Q000379:methods*; D002941:Circle of Willis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D002532:Intracranial Aneurysm / Q000150:complications / Q000000981:diagnostic imaging*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology
keywords: High-resolution vessel wall magnetic resonance imaging; Intracranial aneurysm; Magnetic resonance imaging; Subarachnoid Hemorrhage