Calibration and dead time correction for a PET scanner with variable geometry

We aim at developing practical ways to measure the parameters necessary for data corrections and calibration of a PET scanner with variable geometry (ClearPEM), in order to achieve accurate quantitative images for a large range of imaging tasks using few phantom measurements. We used a decaying cylindrical phantom to determine calibration and dead time factors for a set of acquisition geometries that was obtained by varying the distance between detectors. New factors for intermediate distances can then be obtained by interpolation. Normalization correction factors were measured with a planar source of activity using the same distances. The results allowed to assess the dead time correction and calibration factors, indicating that with two simple phantom acquisitions it is possible to calibrate the scanner and obtain the data needed to apply data corrections in order to obtain quantitative images for a large range of imaging applications.