title: Could different hydration protocols affect the quality of 18F-FDG PET/CT images?
abstract: In a group of oncologic patients undergoing (18)F-FDG PET/CT, we compared 4 different protocols of hydration to investigate their impact on image quality and to choose the best practice.
  
  
  METHODS
  One hundred twenty subjects undergoing (18)F-FDG PET/CT were randomized into 4 groups: group A, receiving free oral hydration; group B, receiving an intravenous injection of 10 mg of furosemide and infusion of 500 mL of saline solution starting 5 min after tracer injection; group C, receiving oral hydration with 500 mL of water; and group D, receiving intravenous injection of 10 mg of furosemide and infusion of 250 mL of the saline solution starting 30 min after the (18)F-FDG injection. The maximum standardized uptake value of muscular and adipose tissues, blood pool (aortic and left ventricular cavity), bladder, and renal parenchyma was calculated for each subject.
  
  
  RESULTS
  These 4 groups were comparable in age, body mass index, blood glucose level, and serum creatinine level. Group A showed the worst results. The controlled hydration protocols (groups B, C, and D) provided lower background activity in the soft tissues and lower urinary activity in the bladder and kidney without significant differences in blood activity. The administration of furosemide produces lower activity in the urinary tract without significant changes in (18)F-FDG distribution in the muscle, fat, or blood pool. The best results were in group D.
  
  
  CONCLUSIONS
  Controlled hydration, particularly with standardized parenteral protocols, reduces the background activity in the soft tissues with the potential benefit of increasing the tumor-to-background contrast. Furosemide does not change tracer distribution in normal tissues but improves the quality of PET/CT images, reducing activity in the excretory system, particularly if the furosemide is administered late after (18)F-FDG injection.
authors.affiliation: Department of Nuclear Medicine and PET/CT Centre, Oncology Institute of Southern Switzerland (IOSI), Bellinzona, Switzerland. luca.ceriani@eoc.ch
authors.forename: Luca
authors.initials: L
authors.lastname: Ceriani
authors.forename: Sergio
authors.initials: S
authors.lastname: Suriano
authors.forename: Teresa
authors.initials: T
authors.lastname: Ruberto
authors.forename: Luca
authors.initials: L
authors.lastname: Giovanella
mesh_terms: D016477:Artifacts; D005440:Fluid Therapy / Q000379:methods*; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011786:Quality Control; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18