title: Characterization of cerebral infarction by multicomponent analysis of transverse magnetization decay curves.
abstract: OBJECTIVE
  Individual components of the transverse magnetization decay curve (TDC) were assessed for their ability to characterize ischemia in photochemically induced cerebral infarcts.
  
  
  METHODS
  Fifty rats were randomly divided into equal-sized experimental and control groups, which were subdivided into groups studied at five different time points, ranging from 6 hours to 22 days. All the rats received transcalvarial irradiation with 560-nm light. Five rats in each time group also received a sensitizing dye before irradiation. In these latter animals, lesions of uniform size and location developed. Lesions were compared with tissue of similar volume and location from the contralateral cortex of the experimental animals and with tissue from both hemispheres of the control animals. TDCs of all the samples were measured and fit with mono- and bi-exponential functions.
  
  
  RESULTS
  Unlike the control tissue, infarcted tissue displayed definitive two-component TDC behavior. The time course of the bi-exponential parameters yielded information unavailable from mono-exponential analyses.
  
  
  CONCLUSIONS
  Bi-exponential analysis of TDCs may have diagnostic use as a more sensitive indicator of cerebral infarction than mono-exponential analyses.
authors.affiliation: Tufts University School of Veterinary Medicine, North Grafton, Massachusetts 01536.
authors.forename: L J
authors.initials: LJ
authors.lastname: Kleine
authors.forename: R V
authors.initials: RV
authors.lastname: Mulkern
authors.forename: F A
authors.initials: FA
authors.lastname: Jolesz
authors.forename: T
authors.initials: T
authors.lastname: Sandor
authors.forename: V A
authors.initials: VA
authors.lastname: Colucci
authors.forename: D
authors.initials: D
authors.lastname: Zamaroczy
authors.forename: M
authors.initials: M
authors.lastname: Podell
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology*; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000209:etiology; D002542:Intracranial Embolism and Thrombosis / Q000209:etiology; D008027:Light / Q000009:adverse effects; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D051381:Rats; D011919:Rats, Inbred Strains; D012395:Rose Bengal
chemical_list: D012395:Rose Bengal