title: The magnetization transfer effect in cerebral infarction.
abstract: OBJECTIVE
  To estimate the age of cerebral infarcts using magnetization transfer.
  
  
  METHODS
  Twelve patients with radiographically and clinically documented cortical and subcortical cerebral infarctions underwent MR imaging on a 0.1T magnet. Magnetization transfer contrast images were generated by application of off-resonance pulses to every other repetition time on intermediate-weighted images. The magnetization transfer effect was calculated by obtaining an intensity value in the region of interest within the infarcted area.
  
  
  RESULTS
  The data show a pattern in which the magnetization transfer effect decreases as the chronicity of the infarct increases. Infarcts less than 1 week old had an average magnetization transfer effect of 0.35. Those more than 1 week and less than 1 month old average 0.30. Infarcts more than 1 month and specifically those more than 1 year old averaged 0.16 or less.
  
  
  CONCLUSIONS
  Magnetization transfer offers the potential to estimate the age of cerebral infarcts.
authors.affiliation: Department of Radiology, University of Chicago Hospitals, IL.
authors.forename: J M
authors.initials: JM
authors.lastname: Prager
authors.forename: J D
authors.initials: JD
authors.lastname: Rosenblum
authors.forename: D C
authors.initials: DC
authors.lastname: Huddle
authors.forename: C K
authors.initials: CK
authors.lastname: Diamond
authors.forename: C E
authors.initials: CE
authors.lastname: Metz
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002540:Cerebral Cortex / Q000473:pathology; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000473:pathology; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014057:Tomography, X-Ray Computed