An approximately 185 MBq (5 mCi S) Tc-99m SPECT processed with WBR provides adequate image quality. For larger patients prolonging image acquisition to 16 minutes is beneficial. For patients with normal S SPECT, a S-only protocol is feasible, affording them a very low (approximately 1.4 mSv) radiation dose. If subsequent R SPECT is necessary, it can be performed with approximately 1,332 MBq (36 mCi) with minimal S-R "shine-through."

Compton scatter from radiotracer in structures close to the heart may partially or completely mask myocardial perfusion defects on SPECT imaging. Previous reports have discussed benefits of additional delayed imaging. We present a case in which additional delayed stress imaging reduced Compton scatter and unveiled clinically significant, stress-induced ischemia.