Ge discovery ls pet ct system

Five scans were referred studies from outside institutions with varying imaging techniques. For FDG PET/CT studies conducted at St. Jude, 5.5 MBq/kg FDG (maximum 444 MBq) was injected intravenously after either overnight fasting or a minimum of 4 hours of fasting for afternoon scans. Blood glucose was found to be normal before FDG injection. Patients were kept in a quiet, dark room after injection and were instructed to relax with their arms at their sides in a recumbent position. Approximately 1 hour later, attenuation correction and lesion localization by transmission CT images and PET emission images were acquired using a GE Discovery LS PET/CT system (GE Medical Systems, Waukesha, WI). CT acquisition parameters were: tube rotation 0.8 second, slice thickness 0.5 cm, table speed 1.5 cm/rotation, pitch 1.5:1, 120 kV, 90 mA, with dose modulation. Whole body PET images were obtained from the top of skull to the feet for 5 minutes per bed position in two-dimensional mode. All but one scan included extremities. Scans obtained after July 2011 were acquired on a GE Discovery 690 PET/CT system. Those emission images were acquired in three-dimensional mode.