A nuclear medicine imaging device includes a plurality of detector heads (10) mounted to a movable gantry for rotation around an examination region (12). The detector heads (10) include a housing (28) which surrounds a radiation sensitive crystal (26) which converts received radiation events. A positioning mechanism on the gantry maintains a relationship between the detector heads (10) such that the housing for one detector head lies adjacent to and overlaps the housing for another detector head. During an imaging event, the gantry rotates the detector heads (10) about a region of interest (12) while radiation events are sampled. At a predetermined position relative to the area of interest, the overlapping of the detector heads is reversed.