title: Global White Matter Hypoperfusion on CT Predicts Larger Infarcts and Hemorrhagic Transformation after Acute Ischemia.
abstract: BACKGROUND
  Presence of white matter hyperintensity (WMH) on MRI is a marker of cerebral small vessel disease and is associated with increased small vessel stroke and increased risk of hemorrhagic transformation (HT) after thrombolysis.
  
  
  OBJECTIVE
  We sought to determine whether white matter hypoperfusion (WMHP) on perfusion CT (CTP) was related to WMH, and if WMHP predisposed to acute lacunar stroke subtype and HT after thrombolysis.
  
  
  METHODS
  Acute ischemic stroke patients within 12 h of symptom onset at 2 centers were prospectively recruited between 2011 and 2013 for the International Stroke Perfusion Imaging Registry. Participants routinely underwent baseline CT imaging, including CTP, and follow-up imaging with MRI at 24 h.
  
  
  RESULTS
  Of 229 ischemic stroke patients, 108 were Caucasians and 121 Chinese. In the contralateral white matter, patients with acute lacunar stroke had lower cerebral blood flow (CBF) and cerebral blood volume (CBV), compared to those with other stroke subtypes (P = 0.041). There were 46 patients with HT, and WMHP was associated with increased risk of HT (R(2) = 0.417, P = 0.002). Compared to previously reported predictors of HT, WMHP performed better than infarct core volume (R(2) = 0.341, P = 0.034), very low CBV volume (R(2) = 0.249, P = 0.026), and severely delayed perfusion (Tmax>14 second R(2) = 0.372, P = 0.011). Patients with WMHP also had larger acute infarcts and increased infarct growth compared to those without WMHP (mean 28 mL vs. 13 mL P < 0.001).
  
  
  CONCLUSIONS
  White matter hypoperfusion remote to the acutely ischemic region on CTP is a marker of small vessel disease and was associated with increased HT, larger acute infarct cores, and greater infarct growth.
authors.affiliation: Departments of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Bivard
authors.affiliation: Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Departments of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
authors.forename: Long-Ting
authors.initials: LT
authors.lastname: Lin
authors.affiliation: Departments of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
authors.forename: Christopher
authors.initials: C
authors.lastname: Levi
authors.affiliation: Departments of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
authors.forename: Neil
authors.initials: N
authors.lastname: Spratt
authors.affiliation: Department of Neurology, Royal Adelaide Hospital, Adelaide, NSW, Australia.
authors.forename: Tim
authors.initials: T
authors.lastname: Kleinig
authors.affiliation: Department of Neurology, Gosford Hospital, Gosford, NSW, Australia.
authors.forename: Billy
authors.initials: B
authors.lastname: O'Brien
authors.affiliation: Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Butcher
authors.affiliation: Department of Neurology, the Second Affiliated Hospital of Zhejiang University, Hangzhou, China.
authors.forename: Min
authors.initials: M
authors.lastname: Lou
authors.affiliation: Department of Neurology, Baotou Central Hospital, Baotou, China.
authors.forename: Jing-Fen
authors.initials: JF
authors.lastname: Zhang
authors.affiliation: Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India.
authors.forename: P N
authors.initials: PN
authors.lastname: Sylaja
authors.affiliation: Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China.
authors.forename: Wen-Jie
authors.initials: WJ
authors.lastname: Cao
authors.affiliation: Department of Neurology, The Queen Elizabeth Hospital, Adelaide, NSW, Australia.
authors.forename: Jim
authors.initials: J
authors.lastname: Jannes
authors.affiliation: Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Dong
authors.affiliation: Departments of Neurology, John Hunter Hospital, University of Newcastle, Newcastle, NSW, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Parsons
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020520:Brain Infarction / Q000209:etiology*; D002545:Brain Ischemia / Q000150:complications* / Q000473:pathology*; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D055420:Perfusion Imaging; D011446:Prospective Studies; D012189:Retrospective Studies; D020521:Stroke / Q000209:etiology; D066127:White Matter / Q000473:pathology*
keywords: CTP; Intracerebral Hemorrhage; Small vessel disease; White matter disease; White matter hyper intensity