Masking Effect of Radiopharmaceutical Dose Extravasation During Injection on Myocardial Perfusion Defects During SPECT Myocardial Perfusion Imaging: A Potential Source of False Negative Result

Proper interpretation of SPECT myocardial perfusion imaging (MPI) is primarily based on strict adherence to standard procedural protocols from patient preparation to image processing and display. Inadvertent faulty injection of the radiopharmaceutical and, consequently, dose extravasation during SPECT MPI is a more important issue than that in any other diagnostic scintigraphic procedure. As it can be considered as a major source of false negative result, clinician’s awareness of this problem during interpretation is of great importance. In some occasions, no local clinical signs or image findings may be available to the interpreter to be aware of dose extravasation to adopt a suitable approach. Herein, we present a case with dose extravasation during stress phase, which is repeated another day with the same protocol, and the potential effects of dose extravasation on SPECT myocardial perfusion images from different aspects and useful image findings as hints are provided.