METHODS FOR IMPROVING IMAGE QUALITY IN WHOLE-BODY PET SCANNING

Whole body PET imaging is performed by acquiring data at multiple axial positions. From this data set, coronal and sagittal cross sectional images are formed by reorienting the transaxial tomographic images. Due to the short acquisition time at each axial position the noise levels in the final images are relatively high. The aim of this work is to optimize some of the scanning parameters for whole body PET imaging to achieve best possible image quality. The detection efficiency of the PET system can be improved by using more coincidence plane combinations in addition to the conventional direct and cross planes. The effect of acquiring an additional set of coincidence planes with a plane separation of +/- 2 was studied and showed a reduction in noise and improved uniformity without a significant loss in resolution. The effect of different sampling schemes were also studied. Using a continuous sampling scheme by moving the bed in steps equal to half the plane separation resulted in better image uniformity together with a reduction in noise in comparison with images acquired using the standard interleaved sampling mode.