title: The clinical significance of reverse redistribution in Tl201 cardiac SPET.
abstract: In an attempt to evaluate the clinical significance of reverse redistribution in Tl201 cardiac SPET, Tl201 SPET examinations included in the data base of our department have been retrospectively reviewed.
  
  
  METHODS
  Six hundred ninety eight patients demonstrated the pattern of reverse redistribution. For 237 of these patients' cardiac catheterization data were also available. One hundred and six patients of these had a history of myocardial infarction while the rest of them were referred for angina symptoms.
  
  
  RESULTS
  Catheterization showed that the infarction area was perfused by a stenosed but patent vessel in 79 of the 106 patients with a history of myocardial infarction (74.5%). Collateral circulation was evident in 21 of these 106 patients (19.8%). Only six patients (5.6%) showed a totally occluded vessel with no obvious evidence of collateral circulation. Of the 131 patients, with no myocardial infarction history, 14 (10.7%) had normal coronary vessels. The rest of the patients (89.3%) demonstrated stenotic vessels perfusing the same area where reverse redistribution was observed. Sixty-three of these patients have been reexamined after 9-36 months. On 15 of these patients (23.8%) the second scintigram showed ischemia in the same segments where reverse redistribution was initially detected. Another 17 of the above patients had a former scintigraphic examination that showed ischemia on the segments that currently demonstrated reverse redistribution.
  
  
  CONCLUSIONS
  The results of the present retrospective study indicate that, in patients with known coronary disease, the pattern of reverse redistribution frequently indicates the ischemic area.
authors.affiliation: Hippocrates Nuclear Medicine Center, Thessaloniki, Greece. koliakos@med.auth.gr
authors.forename: G
authors.initials: G
authors.lastname: Koliakos
authors.forename: A
authors.initials: A
authors.lastname: Doumas
authors.forename: D
authors.initials: D
authors.lastname: Altas
authors.forename: G
authors.initials: G
authors.lastname: Louridas
mesh_terms: D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006328:Cardiac Catheterization; D003097:Collateral Circulation / Q000502:physiology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012189:Retrospective Studies; D013794:Thallium Radioisotopes / Q000493:pharmacokinetics*; D014018:Tissue Distribution / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D013794:Thallium Radioisotopes