July 23, 2007 - Scientists at Duke University combine the best aspects of X-ray computed tomography (CT) scanning with single photon emission computed tomography (SPECT), which is the single-gamma-ray counterpart of positron emission tomography (PET) scans, to obtain both anatomical and functional information using a single comfortable gantry. The computer reconstruction of the continuously acquired data employs an iterative algorithm that handles both CT and SPECT data in turn. The new features of this hybrid system include, first on the SPECT side, a spatial resolution of 2.5 mm and an energy resolution of 6%. On the computed tomography (CT) side, with a dose as low as one-tenth that used in normal X-ray screening mammography, the imaging can reveal normally hard-to-see lesions near the chest wall, and the spatial resolution is 0.5 mm. The SPECT imaging detects biochemical changes long before structural changes are observable, a valuable feature for early screening or for following therapy. Martin Tornai says that early clinical trials of the new device are going well.