Comparison of myocardial blood flow SPECT imagingwith ²⁰¹Tl with guidelines

In this study, we compared myocardial blood flow single photon emission computed tomography (SPECT) using technetium-99m (^99mTc) and thalium-201 (²⁰¹Tl) preparations.

An the EMIT phantom was used to confirm that the ^99mTc formulation met the criteria of the "myocardial blood flow SPECT standardization guidelines", and ²⁰¹Tl formulation was imaging performed under the same conditions.

In the physical evaluation, no significant differences were found in differential homogeneity and % counts. However, in the evaluation using the RH-2 phantom, increasing the ²⁰¹Tl concentration from 2% to 4% decreased the difference from the ^99mTc preparation in the bull's eye display.

The lack of differences in physical and visual evaluations despite different collection energies and doses may be because the number of gates and matrix size remained constant. These results suggest that imaging conditions that meet the criteria for ^99mTc formulations can be applied to ²⁰¹Tl formulations.