title: Cerebral perfusion SPECT in transient ischemic attack.
abstract: OBJECTIVE
  The purpose of our study is to evaluate the efficacy of cerebral perfusion single photon emission computerized tomography (SPECT) in patients with transient ischemic attack (TIA).
  
  
  METHODS
  Thirty-seven patients with TIA were collected for study. All patients had transient focal neurological symptoms or signs with complete recovery within 24 h after onset. The patients underwent cerebral perfusion SPECT between 6 h and 11 days after onset, with 10 cases performed within 24 h (group A), nine cases performed between 1 and 3 days (group B), 11 cases performed between 3 and 5 days (group C), and seven cases performed after more than 5 days (group D). A semi-quantitative method was used for analyzing the SPECT data, and the difference ratios between lesion side and contralateral normal side were calculated on each pair of regions of interest.
  
  
  RESULTS
  In total, 78.4% (29/37) of patients had reduced perfusion in the cerebral cortical regions or deep nuclei, and the regions with reduced perfusion corresponded with clinical presentations of the patients. The abnormal rate with reduced perfusion was 90.0% in group A, 77.8% in group B, 72.7% in group C and 71.4% in group D. Cross cerebellar diaschisis (CCD) was present in seven patients, and all of the primary cerebral perfusion defects of these patients were located at the territory of left or right middle cerebral artery.
  
  
  CONCLUSIONS
  Cerebral perfusion SPECT is a potential tool to detect cerebral perfusion defects and CCD in patients with TIA. Although the perfusion defect may persist more than 5 days after onset, we suggest cerebral perfusion SPECT should be performed as soon as possible.
authors.affiliation: Department of Nuclear Medicine. Koo Foundation, Sun Yat-Sen Cancer Center, 125 Lih-Der Road, Taipei, Taiwan. dlyou@mail.kfcc.org.tw
authors.forename: D L
authors.initials: DL
authors.lastname: You
authors.forename: F Y
authors.initials: FY
authors.lastname: Shieh
authors.forename: K Y
authors.initials: KY
authors.lastname: Tzen
authors.forename: M F
authors.initials: MF
authors.lastname: Tsai
authors.forename: P F
authors.initials: PF
authors.lastname: Kao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015899:Tomography, Emission-Computed, Single-Photon