Abstract: In the present invention, a tomographic emission scanner has a detection chamber with an axial center line and an axial periphery, and a plurality of single element emission detector units are positioned around the axial periphery of the detection chamber. Each detector unit includes a single detecting element having a detection face oriented toward the detection chamber. The detection face of each detecting element is curved along the axial periphery of the detection chamber.

Abstract: A tomographic emission scanner has a detection chamber with an axial center line and an axial periphery, a positron emission coincidence detection circuit, and a number of positron emission detector units that are positioned around the axial periphery of the detection chamber. Each detector unit is operatively coupled to the detection circuit and has a detection face oriented toward the detection chamber. Each detector unit is circumferentially movable about the axial periphery of the detection chamber. In one embodiment, at least one of the detector units is independently movable with respect to any other detector unit. In another embodiment, the scanner also has a resting surface at least partially positioned within the detection chamber. The resting surface extends parallel to and is radially movable with respect to the axial center line. The resting surface is also circumferentially movable with respect to the axial center line while continuously facing upward.