The importance of a correct positioning of the heart using IQ-SPECT system with multifocal collimators in myocardial perfusion imaging: a phantom study.

Background: We have recently validated a quarter-time protocol in Myocardial Perfusion Imaging named IQ-SPECT, whose basic principle is to implement a multifocal collimator; However, in clinical practice, it may sometimes be difficult to center the heart in the region of highest magnification of the multifocal collimators (the so-called sweet spot). We therefore aimed to evaluate whether a heart mispositioning may affect results in MPI.

Methods: We simulated a rest study with an anthropomorphic phantom with an in vivo distribution of 400 MBq [(99m)Tc]tetrofosmin, with and without a transmural defect (TD).