1. A nuclear imaging device comprising: a detector for detecting radiation emitted from within a patient and providing a data set indicative of the detected radiation, a reconstruction unit for reconstructing, in a series of iterations updated image objects, wherein each iteration step includes determining a data model from an input image object, the input image object of a first iteration being the initial image object and the input image objects of subsequent iterations being the updated image objects from previous iterations, and determining a stop-criterion of the data model on the basis of a chi-square-gamma statistic; an evaluation unit interacting with the reconstruction unit for determining that the stop-criterion of the data model has transitioned from being outside a limitation of a threshold value to being inside the limitation, the stop-criterion or the threshold being a function of a statistical value of the chi-square gamma statistic, the stop-criterion or the threshold varying by spatial location and being weighted toward a region of interest within the volume, ending the iterations, selecting one of the updated image objects to be the reconstructed image object; and a display for displaying an image of the updated image object.