Compton scatter compensation using the triple-energy window method for single- and dual-isotope SPECT.

The spatial distribution of scattered photons varies depending on many factors such as object size and source distribution. We propose a triple-energy window (TEW) scatter compensation method for determining position-dependent Compton scatter. We estimated the count of primary photons at each pixel in the acquired image using the 24% main window centered at the photo peak energy and 3 keV scatter rejection windows on both sides of the main window. We conducted a physical evaluation of this method using phantoms and also applied this method to patients in a clinical trial. The TEW method performed Compton scatter compensation with good accuracy.