Scatter corrections for simultaneously acquired dual-isotope SPECT imaging using three windows
The feasibility of using a third energy window (EW) is investigated for rest 201Tl/stress 99mTc scatter corrections in order to obtain improved quantification and image quality compared with dual-isotope myocardial perfusion imaging using two photopeak energy windows (PEWs). To obtain the relationship between the intermediate EW (IEW) and dual-isotope scatter EWs (SEWs), five different EWs, including an IEW between the dual-isotope are used. It is indicated that the crosstalk into each PEW measured with a cardiac phantom is similar in air, however, in water 99mTc to 201Tl crosstalk is greater than twice of that in air. After attenuation and scatter compensation, the qualitative analysis and image quality are improved compared with dual-isotope imaging which used two PEWs, especially with 2011 scans acquired in the presence of background activity.
