title: Variations in clinical PET/CT operations: results of an international survey of active PET/CT users.
abstract: This study gathered information about clinical PET/CT operations worldwide to help guide discussions on the use and standardization of clinical PET/CT.
  
  
  METHODS
  A Web-based survey of PET/CT users was initiated in November 2009 through e-mail advertising using Academy of Molecular Imaging databases. Recipients were asked 58 questions related to demographics (e.g., location, number of PET/CT systems, and staffing), PET/CT operations and use, and variations in (18)F-FDG oncology imaging protocols.
  
  
  RESULTS
  The responders were from centers in the Americas (71%), Europe (22%), Asia-Pacific (6%), and Middle East (1%), with most responding sites representing public health care institutions (60%). PET/CT systems were most frequently installed in nuclear medicine departments (59%). Of the sites operating a PET/CT system, 16% had 10 y or more of stand-alone PET experience. About 40% of all sites operated at least 2 PET/CT systems. PET/CT was most frequently used for applications in torso or whole-body oncology (87%), radiation therapy planning (4%), cardiology (4%), and neurology (5%). The average interval of fasting before an (18)F-FDG PET/CT examination was 7 ± 3 h (range, 4-12 h). Blood glucose levels were measured at 99% of sites, but acceptable maximal glucose levels varied substantially (an upper limit of 200 mg/dL was applied at >50% of the institutions). A weight-based radioactivity dose injection was performed at 44% of sites. The mean (18)F-FDG activity injected was 390 MBq (range, 110-585 MBq) for 3-dimensional PET of a 75-kg patient. The mean uptake time was 64 ± 14 min (range, 20-90 min). Split protocols involving patient repositioning and adapted imaging parameters were used at 51% of sites. Only 41% used patient positioning aids. Intravenous or oral CT contrast material was used at 52% of sites in up to 25% of patients. Most sites (90%) measured maximum standardized uptake value as an index of tissue glucose use. Only 62% of sites provided a fully integrated PET/CT report.
  
  
  CONCLUSIONS
  An international survey among clinical PET/CT users revealed significant variations in standard (18)F-FDG PET/CT protocols. This finding illustrates the need for continuous training and ongoing standardization in an effort to optimize PET/CT in oncology.
authors.affiliation: Department of Nuclear Medicine, University Hospital Essen, Essen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Beyer
authors.forename: Johannes
authors.initials: J
authors.lastname: Czernin
authors.forename: Lutz S
authors.initials: LS
authors.lastname: Freudenberg
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D017357:Cyclotrons; D003625:Data Collection; D004032:Diet; D019788:Fluorodeoxyglucose F18 / Q000592:standards; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000592:standards; D049268:Positron-Emission Tomography / Q000295:instrumentation / Q000592:standards*; D019275:Radiopharmaceuticals / Q000592:standards; D012015:Reference Standards; D014055:Tomography, Emission-Computed / Q000295:instrumentation / Q000592:standards*
chemical_list: D001786:Blood Glucose; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18