The suitability of gamma camera coincidence systems for nitrogen 13–labeled ammonia myocardial perfusion imaging: a quantitative comparison with full-ring PET

• Published in: Journal of nuclear cardiology 2003-11, Vol.10 (6), p.633-643
• Main Authors: McKiddie, Fergus I, Gemmell, Howard G, Davidson, E.Joyce, Welch, Andrew, Egred, Mohaned
• Format: Article
• Language: English
• Subjects: Aged; Ammonia; Cardiomyopathies - complications; Cardiomyopathies - diagnosis; Cardiomyopathies - diagnostic imaging; Equipment Failure Analysis; Female; Gamma camera coincidence imaging; Gamma Cameras; Heart Ventricles - diagnostic imaging; Humans; Male; Middle Aged; myocardial perfusion; myocardial viability; nitrogen 13–labeled ammonia; Nitrogen Radioisotopes; positron emission tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography; Tomography, Emission-Computed - instrumentation; Tomography, Emission-Computed - methods; Ventricular Dysfunction, Left - diagnosis; Ventricular Dysfunction, Left - diagnostic imaging; Ventricular Dysfunction, Left - etiology
• ISSN: 1071-3581; 1532-6551
• DOI: 10.1016/S1071-3581(03)00658-5

The aim of this study was to examine the quality of nitrogen 13–labeled ammonia (NH 3) perfusion data from coincidence-capable gamma camera positron emission tomography (GC-PET) systems compared with that from full-ring positron emission tomography (FR-PET). The performance parameters of the GC-PET system were examined and found adequate for imaging at the activity levels used clinically. We studied 15 patients who underwent stress and rest N-13–labeled NH 3 perfusion imaging on FR-PET and GC-PET systems. Quantitative analysis of perfusion values showed that GC-PET uptake was significantly lower than FR-PET uptake in 67.6% of segments. Bland-Altman analysis showed that the mean difference between FR-PET and GC-PET values was from 5.3% to 5.9%. Stress FR-PET identified 49 segments as having impaired perfusion, 46 (93.9%) of which were also identified by GC-PET. Fifty-six additional segments were identified as abnormal by GC-PET. These findings indicated a general overestimation of defect size on GC-PET. Analysis of the degree of perfusion reduction also found that GC-PET tended to overestimate defect contrast. These findings are similar to those previously found by workers examining fluorine 18–fluorodeoxyglucose uptake by both techniques. Good concordance was shown between GC-PET and FR-PET systems for N-13–labeled NH 3 perfusion imaging, although further work is required to optimize the technique.