Metabolic activity in the areas of new fill-in after thallium-201 reinjection: comparison with positron emission tomography using fluorine-18-deoxyglucose

J Nucl Med. 1991 Apr;32(4):673-8.

Abstract

Reinjection of thallium-201 after recording the 3-hr delayed scan often demonstrates improvement in areas of persistent abnormalities. To determine the metabolic activity of these areas, the changes seen on stress/redistribution/reinjection thallium SPECT were compared with PET using fluorine-18-fluorodeoxyglucose (FDG) in 18 patients with coronary artery disease. Of 48 segments showing no redistribution on the delayed scan, the reinjection scan identified new fill-in in 20 segments (42%), all of which demonstrated FDG uptake. In contrast, only 7 of the 28 segments (25%) showing no fill-in after reinjection were PET viable (p less than 0.01). Eleven patients had coronary bypass graft surgery after the radionuclide study. The majority of the segments showing redistribution (87%) and new fill-in after reinjection (65%) improved in wall motion, whereas only eight segments (25%) without new fill-in improved after surgery. Of those without new fill-in, two segments showing PET ischemia improved in wall motion, whereas the remaining six segments showing PET scar did not improve after surgery. Thus, the segments showing new fill-in after reinjection are PET viable myocardium. However, reinjection thallium imaging still underestimates the extent of tissue viability compared to PET imaging.

Publication types

  • Comparative Study

MeSH terms

  • Coronary Circulation / physiology
  • Coronary Disease / diagnostic imaging*
  • Coronary Disease / physiopathology
  • Deoxyglucose / analogs & derivatives*
  • Fluorine Radioisotopes*
  • Fluorodeoxyglucose F18
  • Humans
  • Middle Aged
  • Myocardial Contraction / physiology
  • Myocardium / metabolism*
  • Thallium Radioisotopes* / administration & dosage
  • Tomography, Emission-Computed*
  • Tomography, Emission-Computed, Single-Photon*

Substances

  • Fluorine Radioisotopes
  • Thallium Radioisotopes
  • Fluorodeoxyglucose F18
  • Deoxyglucose