title: Silent ischemic lesion recurrence on magnetic resonance imaging predicts subsequent clinical vascular events.
abstract: BACKGROUND
  Previous studies identified a high frequency of silent ischemic lesion recurrence on magnetic resonance imaging (MRI) after an index stroke.
  
  
  OBJECTIVE
  To investigate whether ischemic lesion recurrence on MRI predicts subsequent clinical events.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  General community hospital. Patients We recruited 120 patients who experienced an acute ischemic stroke (IS) and who underwent initial MRI within 24 hours of onset and subsequent MRI on day 5. Of those patients, 68 underwent follow-up MRI up to 90 days after onset.
  
  
  METHODS
  Early silent lesion recurrence was defined as new asymptomatic ischemic lesions on 5-day MRI, and late silent lesion recurrence was defined as those on 30- or 90-day MRI. Patients were followed up for recurrent vascular events by interviews.
  
  
  RESULTS
  Among the 104 patients (86.7%) who had available clinical outcome data, 35 (33.7%) had early silent lesion recurrence; 15 (22.1%) of 68 patients had late silent lesion recurrence. Of the patients, 8 experienced a recurrent IS, 3 experienced a transient ischemic attack, and 3 had vascular deaths during a mean +/- SD follow-up of 19.3 +/- 9.0 months. For recurrent IS as a clinical end point, late silent lesion recurrence independently predicted recurrent IS (odds ratio, 6.55; 95% confidence interval, 1.09-39.55) by the Cox proportional hazards model. For combined clinical end points, early (odds ratio, 3.19; 95% confidence interval, 1.02-10.00) and late (odds ratio, 8.09; 95% confidence interval, 1.29-50.91) silent lesion recurrences independently predicted clinical recurrent IS, transient ischemic attack, or vascular deaths.
  
  
  CONCLUSIONS
  These data suggest that silent ischemic lesion recurrence on MRI may be a potential surrogate marker of clinical recurrence.
authors.affiliation: Stroke Branch, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA.
authors.forename: Dong-Wha
authors.initials: DW
authors.lastname: Kang
authors.forename: Susan U
authors.initials: SU
authors.lastname: Lattimore
authors.forename: Lawrence L
authors.initials: LL
authors.lastname: Latour
authors.forename: Steven
authors.initials: S
authors.lastname: Warach
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000473:pathology*; D002561:Cerebrovascular Disorders / Q000175:diagnosis*; D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012008:Recurrence; D012189:Retrospective Studies; D020521:Stroke / Q000175:diagnosis