The evaluation and comparison of the prone method and using a physical shield in order to reduce artifacts caused by sub-diaphragmatic activity in the myocardial perfusion imaging of SPECT

Background: Subdiaphragmatic activity contributes to inferior wall artifacts in technetium 99m myocardial perfusion single photon emission computed tomography (SPECT). Imaging in the prone position has been suggested as a method to overcome this problem. The aim of this study was to evaluate the impact of using a physical shield in routine supine position image for reducing this kind of artifact and compare the achieved result with the result of the prone position.Methods: A total of 32 patients with no information about coronary artery disease (CAD) who underwent single-day 99mTc-sestamibi stress/rest SPECT, were enrolled in the study. All patients had routine ECG-gated supine SPECT imaging, supine SPECT imaging along with a physical shield, and prone position SPECT imaging. Summed Stress Score (SSS) obtained by Oasis hardware and two nuclear medicine physician and one cardiologist have been used to interpret the results of supine position (with physical shield) and prone position.Results: The patient who doesn’t have inferior defect were excluded from this. The SSS for the supine along with a physical shield, and prone, were 5.37±4.17, and 6±3.88, respectively (P=0.001). Three physicians had following recognition about images’ result. Supine images had a better result by 57.83%, prone images had a better result by 17.66%, and prone images had the same result as supine images by 24.51%. Statistical analysis demonstrated that there is no statistically significant difference between the mean SSS of supine with a physical shield and mean SSS of prone studies (α =0.05).Conclusion: Technetium-99m (99m Tc) sestamibi MPI in the patient with physical shield has the same result and in some case provides greater diagnostic accuracy than prone imaging; moreover, it provides an inexpensive, comfortable approach for old people to overcome subdiaphragmatic artifact.

کلیدواژه ها:

MPI SPECT ، Sub-diaphragmatic artifact ، Prone ، Physical shield