Sources of variability of gated myocardial perfusion SPECT quantitative parameters

Excerpt

In the current issue of the Journal of Nuclear Cardiology in a manuscript entitled “Adopting New Gamma Cameras and Reconstruction Algorithms: Do We Need to Establish Normal Reference Values?” by TL Miao et al, the authors demonstrate variability of gated myocardial perfusion SPECT functional parameters attributable to gender and scintillation camera type.1 As demonstrated previously by others, volumes are smaller in women. In addition, they demonstrated that left ventricular end-diastolic and end-systolic volumes are smaller in SPECT studies acquired with a solid-state CZT camera and processed with the associated software as compared to those acquired with conventional NaI cameras (one supine and the other semi-sitting) and processed with associated software. One factor they acknowledged that confounded their comparisons was a smaller body habitus of patients imaged with the solid-state CZT camera. This report suggests and emphasizes the multitudinous factors that affect quantitative myocardial perfusion function and perfusion SPECT parameters. The reader is reminded of the great many radiopharmaceutical, hardware-, software-, and patient-related factors that influence the quantitative parameters we use routinely to risk-stratify patients and influence their management. …