title: Frequency of subclinical lacunar infarcts in ischemic leukoaraiosis and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.
abstract: OBJECTIVE
  Small vessel cerebrovascular disease is an important cause of vascular cognitive impairment. It is usually sporadic but also occurs secondary to the genetic disorder cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Recurrent lacunar stroke is a characteristic feature, although symptomatic events are relatively rare, making large numbers necessary for evaluation of potential therapies. Diffusion-weighted imaging is sensitive to acute ischemic lesions and differentiates them from chronic infarcts. Detection of asymptomatic lacunar infarcts with diffusion-weighted imaging is a potential surrogate marker for treatment trials. In this study, the frequency of asymptomatic new lesions in ischemic leukoaraiosis and CADASIL was determined as a step toward assessing the potential of this technique as a surrogate marker of disease activity.
  
  
  METHODS
  Fifty patients with sporadic small vessel disease and 19 patients with CADASIL underwent diffusion-weighted imaging. All had been asymptomatic for 3 months before imaging. Diffusion-weighted images were screened by two raters for new lesions; lesions were confirmed as recent by a visible reduction of diffusivity on the corresponding apparent diffusion coefficient maps.
  
  
  RESULTS
  Recent ischemic lesions were identified in four patients with sporadic small vessel disease (8.0%) and two patients with CADASIL (10.5%).
  
  
  CONCLUSIONS
  Asymptomatic new lesions are found in cases of sporadic small vessel disease and CADASIL. The frequency of new lesions suggests that this approach has a potential role as a surrogate marker in therapeutic trials that warrants further investigation.
authors.affiliation: Division of Clinical Neuroscience, St. George's Hospital Medical School, London, England.
authors.forename: Michael
authors.initials: M
authors.lastname: O'Sullivan
authors.forename: Philip M
authors.initials: PM
authors.lastname: Rich
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Barrick
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Clark
authors.forename: Hugh S
authors.initials: HS
authors.lastname: Markus
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020520:Brain Infarction / Q000175:diagnosis* / Q000453:epidemiology; D002545:Brain Ischemia / Q000175:diagnosis* / Q000453:epidemiology; D002539:Cerebral Arterial Diseases / Q000175:diagnosis* / Q000235:genetics; D002544:Cerebral Infarction / Q000175:diagnosis / Q000453:epidemiology; D015331:Cohort Studies; D015161:Dementia, Multi-Infarct / Q000175:diagnosis / Q000453:epidemiology; D015140:Dementia, Vascular / Q000175:diagnosis* / Q000453:epidemiology; D038524:Diffusion Magnetic Resonance Imaging; D020821:Dystonic Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D006113:United Kingdom / Q000453:epidemiology