title: Hemispheric revascularization in the setting of carotid occlusion and subclavian steal: a diagnostic and management role for quantitative magnetic resonance angiography?
abstract: OBJECTIVE
  Advances in phase contrast magnetic resonance imaging have facilitated the noninvasive assessment of blood flow rates and flow direction in patients with complex cerebrovascular disorders.
  
  
  METHODS
  We describe a case of right hemispheric hypoperfusion in which, on noninvasive assessment with quantitative magnetic resonance angiography, the patient was found to harbor an occult subclavian steal with flow reversal in the left vertebral artery.
  
  
  RESULTS
  The presence of posterior communicating arteries noted on quantitative magnetic resonance angiography suggested that normalization of flow in the vertebral arteries by treating the subclavian occlusion could improve flow in the anterior circulation. Angiography confirmed the noninvasive findings, and the subclavian occlusion was treated with angioplasty and stenting. Postintervention quantitative magnetic resonance angiography documented quantitative improvement in right middle cerebral artery flow and restoration of antegrade flow in the left vertebral artery.
  
  
  CONCLUSIONS
  This case illustrates the potential role of noninvasive assessment of blood flow rates and flow direction in the diagnosis, treatment planning, and follow-up of patients with complex cerebrovascular disease.
authors.affiliation: Department of Neurosurgery/INN, St. Luke's-Roosevelt Hospital Center and Albert Einstein College of Medicine, New York, New York 10019, USA. DLanger@chpnet.org
authors.forename: David J
authors.initials: DJ
authors.lastname: Langer
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Lefton
authors.forename: Lauren
authors.initials: L
authors.lastname: Ostergren
authors.forename: Carolyn D
authors.initials: CD
authors.lastname: Brockington
authors.forename: Joon
authors.initials: J
authors.lastname: Song
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Niimi
authors.forename: Peeyush
authors.initials: P
authors.lastname: Bhargava
authors.forename: Alejandro
authors.initials: A
authors.lastname: Berenstein
mesh_terms: D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000601:surgery; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging* / Q000601:surgery; D019468:Disease Management; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D015607:Stents; D013349:Subclavian Steal Syndrome / Q000000981:diagnostic imaging* / Q000601:surgery