title: Branch occlusive disease: clinical and magnetic resonance angiography findings.
abstract: BACKGROUND
  We evaluated the clinicoradiologic characteristics of patients with branch occlusive disease (BOD)-type intracranial atherosclerotic stroke (ICAS) compared with those of patients with non-BOD-type ICAS or with small artery disease (SAD).
  
  
  METHODS
  We analyzed 201 consecutive patients with acute infarcts within the middle cerebral artery (MCA) distribution but no demonstrable carotid or cardiac embolism sources. According to the diffusion-weighted imaging (DWI) distribution and the presence of ipsilateral MCA stenosis, of any degree, on magnetic resonance angiography (3-T MRI), we divided patients into 3 groups: 1) BOD: subcortical infarcts with MCA stenosis (n = 46); 2) non-BOD: infarcts beyond the subcortical area with MCA stenosis (n = 52); and 3) SAD (n = 103). We compared risk factors, degree of stenoses and distribution, and radiologic features of microangiopathy (leukoaraiosis and cerebral microbleeds) among the groups.
  
  
  RESULTS
  Risk factor profiles were similar among the groups, except that hypertension and current smoking were more prevalent in the non-BOD than in the BOD group (p = 0.032 and 0.045). The relevant MCA had more severe and focal stenosis in the non-BOD than in the BOD group (stenosis of ≥70%; 76.9% vs 28.3%; p < 0.001), but the degree of nonrelevant stenosis was similar across the groups. Although clinical features, DWI lesion patterns, and microangiopathy findings were similar between the BOD and SAD groups, nonrelevant stenosis was more prevalent in the BOD than in the SAD group (p < 0.01).
  
  
  CONCLUSIONS
  BOD is prevalent (47% of ICAS) and shares common characteristics with non-BOD-type ICAS, although its clinicoradiologic features may resemble those of SAD. The morphologic characteristics of stenosis and risk factors may associate with a stroke phenotype in patients with ICAS.
authors.affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: S
authors.initials: S
authors.lastname: Ryoo
authors.forename: J H
authors.initials: JH
authors.lastname: Park
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.forename: G-M
authors.initials: GM
authors.lastname: Kim
authors.forename: C-S
authors.initials: CS
authors.lastname: Chung
authors.forename: K H
authors.initials: KH
authors.lastname: Lee
authors.forename: J S
authors.initials: JS
authors.lastname: Kim
authors.forename: O Y
authors.initials: OY
authors.lastname: Bang
mesh_terms: D000368:Aged; D001157:Arterial Occlusive Diseases / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D002545:Brain Ischemia / Q000150:complications; D002533:Cerebral Angiography; D059345:Cerebral Small Vessel Diseases / Q000150:complications / Q000175:diagnosis; D002561:Cerebrovascular Disorders / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D003251:Constriction, Pathologic; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis / Q000473:pathology; D049292:Leukoaraiosis / Q000175:diagnosis / Q000473:pathology; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000145:classification / Q000209:etiology* / Q000473:pathology; D013923:Thromboembolism / Q000150:complications