BACKGROUND: This study was designed to compare the results of rest-redistribution thallium-201 imaging with those of rest technetium 99m furifosmin single photon emission computed tomography in the same patients with chronic ischemic left ventricular (LV) dysfunction. METHODS: Twenty-one patients (mean age 62 +/- 9 years) with chronic myocardial infarction and LV dysfunction (mean LV ejection fraction 34% +/- 8%) underwent rest-redistribution thallium imaging and resting furifosmin single photon emission computed tomography on the same day. In each patient, regional thallium and furifosmin activity was quantitatively measured in 13 myocardial segments. Regional LV function was assessed in corresponding segments by echocardiography. RESULTS: At thallium imaging, 91 (33%) segments had normal uptake, 16 (6%) showed reversible defects, and the remaining 166 (61%) irreversible defects. Of these 166 irreversible defects, 74 (45%) had moderate (> or =58% of peak activity) and 92 (55%) severe (<58% of peak activity) reduction of thallium uptake. Regional furifosmin uptake was significantly related to both rest (r = 0.87, P < .0001) and redistribution (r = 0.90, P < .0001) thallium activity. Agreement in the evaluation of regional perfusion status between thallium and furifosmin imaging was observed in 70% of the 84 hypokinetic segments (kappa = 0.54) and in 76% of the 78 akinetic or dyskinetic segments (kappa = 0.60). Concordance in the detection of myocardial viability between thallium and furifosmin imaging was observed in 69 (82%) of hypokinetic regions (kappa = 0.60) and in 65 (83%) of akinetic or dyskinetic regions (kappa = 0.67). CONCLUSIONS: These results suggest that in patients with chronic coronary artery disease and LV dysfunction, quantitative rest-redistribution thallium scintigraphy and furifosmin tomography at rest provide similar results in the evaluation of perfusion status and in the detection of myocardial viability.

Aged↗

PubMedDate not supplied

99mTc-pyrophosphate kinetics in man (relationship between bone uptake and mineral content).

Both the kinetics and the regional distribution of 99mTc-PPi were studied in the skeleton of healthy subjects of various ages by surface counting using a scintillation counter placed over different skeletal areas. The results were compared with bone mineral content as determined by the photonic absorption technique. Kinetic data of bone uptake were obtained by subtracting the counts measured in blood from the counts recorded over each body surface after making proportional corrections. The surface-counting patterns show a higher generalized 99mTc-PPi bone uptake in children and adolescents than in adults. The relative regional distribution of the tracer shows no difference between the two groups. The tracer accumulated more rapidly in spongy bone than in compact bone, and the fixation process was carried out during the first 30 min for both spongy and compact bone. In youths, however, higher uptake values corresponded to lower values of mineral content. The findings enable the normal surface-counting pattern to be constructed and confirm that the 99mTc-PPi uptake is related to bone metabolism; they also suggest the application of external measurements for the study of metabolic bone diseases.

Adolescent↗

PubMedDate not supplied