 - FDG-PET scan; Image acquisition: Imaging should be performed with dedicated PET-scanners only. Patients will be fasted for at least 6 hours before PET-scanning. Immediately prior to the procedure, patients will be hydrated with 500 ml of water. Blood glucose levels will be measured. Thereafter, FDG 370 MBq when using full-ring systems, 220 MBq when using a half-ring system and 20 mg of furosemide will be injected intravenously. Image acquisition will start 60-75 minutes after FDG injection emission and transmission images of the area between proximal femora and the base of the skull. The images will be corrected for attenuation and reconstructed using the ordered-subsets expectation maximization OSEM algorithm. 