Cardiac Phantom for Gated Single Photon Emission Computed Tomography (GSPECT)

R. A. Hassan, S.H.A. Al Lehyani

Gated single-photon emission computed tomography (GSPECT) is the most important technique for the heart imaging, but the patients instability and the physiological cardiac function variability make studies difficult to evaluation and comparing different imaging techniques. So, a dynamic cardiac phantom (DCP) was constructed at our nuclear medicine unit-National cancer institute, which can be used as a reference to compare the reconstructed volumes & ejection fractions for GSPECT. GSPECT data were acquired using the DCP with a standard dual-head gamma camera, and the reconstructions were carried out using the Mirage software released by Segami. The validity of DCP for GSPECT imaging was evaluated by imaging of 12 different volumes of the phantom.  Linear regression analysis was performed to assess the correlation between the real versus the measured volumes & ejection fractions for all the 12 different volumes. Then we assessed the correlation between real EF and the GSPECT-quantified EF for some acquisition parameters as frame/cycle (8 versus 16), and time/projection (40 versus 20 sec). Results obtained in our study showed that the constructed DCP is suitable to GSPECT imaging.  Also, the study shown that in the case of acquisition parameters it’s enough to using the 8 frames per cardiac cycle with 40 sec time per projection.