title: Xenon contrast CT-CBF measurements in high-intensity foci on T2-weighted MR images in centrum semiovale of asymptomatic individuals.
abstract: OBJECTIVE
  White matter lesions (WMLs) on T2-weighted MR images occurring in the centrum semiovale of normal individuals are a subject of great clinical interest. We therefore investigated regional cerebral blood flow (rCBF) of the centrum semiovale among neurologically normal individuals.
  
  
  METHODS
  One hundred thirty-five neurologically normal subjects were divided into four grades of WML on the basis of their MR images. rCBF values in the centrum semiovale were measured by xenon contrast CT methods.
  
  
  RESULTS
  Advanced age and associated hypertension were significant risk factors for higher grade WMLs. Centrum semiovale rCBF values on the left side were 24.27 +/- 2.60 mL.100 g-1.min-1 in grade 0, 23.52 +/- 2.78 in grade I, 19.35 +/- 2.81 in grade II, 15.82 +/- 2.05 in grade III, and 11.31 +/- 2.56 in grade IV. Differences were significant between grades (P < .005 between grade 0 and grades II, III, and IV; between grade II and grades III and IV; and between grades III and IV). Patients with hypertension had lower rCBF values than those without in grades 0, I, II, and III, with significant difference in grade I (P < .005). Age-matched studies between patients 61 to 70 years old confirmed a significant difference between WML grades.
  
  
  CONCLUSIONS
  WMLs in centrum semiovale are associated with greater age, hypertension, and reduced rCBF values.
authors.affiliation: Department of Neurosurgery, Nasu Neurosurgical Center, Tochigi, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Miyazawa
authors.forename: T
authors.initials: T
authors.lastname: Satoh
authors.forename: K
authors.initials: K
authors.lastname: Hashizume
authors.forename: A
authors.initials: A
authors.lastname: Fukamachi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D002560:Cerebrovascular Circulation; D003287:Contrast Media; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D014978:Xenon
chemical_list: D003287:Contrast Media; D014978:Xenon