title: Fixation devices for whole-body 18F-FDG PET/CT: patient perspectives and technical aspects.
abstract: OBJECTIVE
  To evaluate the use of a fixation device in whole-body postiron emission tomography/computed tomography (PET/CT).
  
  
  METHODS
  Two hundred and thirty patients were prospectively included over a period of 3 months. Different single-phase and multiphase contrast-enhanced PET/CT protocols were used for whole-body examination. An unforced expiration state was applied as breathing protocol for CT examination. Patients were placed on a deflating device (1.0 m x 1.5 m) with arms elevated but supported in order to prevent full extension in shoulders and elbows providing comfortable positioning. Image quality was assessed by means of alignment of the liver quantitatively on co-registered PET/CT images. After the examination, patients were asked to complete a survey on subjective sensations such as pain in different body regions (yes/no). They were asked to give a final evaluation for the whole-body PET/CT examination (comfortable/not comfortable). Additionally, a control group (n=30) was assessed without the aid of additional devices.
  
  
  RESULTS
  Examination protocols using the device showed minor misalignment of 5 mm. Different protocols did not reveal significant differences in misalignment. When comparing the control group misalignment was significantly higher with approx. 7 mm. The majority (75%) evaluated the positioning as comfortable despite 46% of the patients in this group feeling more or less severe pain in at least one body region. For controls, misalignment was slightly higher whereas only 39% found the positioning comfortable (chi(2)=13.03; P<0.0005) and 61% reported pain (NS).
  
  
  CONCLUSIONS
  Both the technical aspects and patient evaluations favour the use of the vacuum device in whole-body PET/CT examinations. In particular, in time consuming protocols using multiphase CT examination the fixation device leads to excellent co-registration quality and patient compliance.
authors.affiliation: Department of Diagnostic Radiology, University of Tuebingen, Tuebingen, Germany. klaus.brechtel@med.uni-tuebingen.de
authors.forename: Klaus
authors.initials: K
authors.lastname: Brechtel
authors.forename: Henriette
authors.initials: H
authors.lastname: Heners
authors.forename: Marc
authors.initials: M
authors.lastname: Mueller
authors.forename: Philip
authors.initials: P
authors.lastname: Aschoff
authors.forename: Susanne M
authors.initials: SM
authors.lastname: Eschmann
authors.forename: Roland
authors.initials: R
authors.lastname: Bares
authors.forename: Claus D
authors.initials: CD
authors.lastname: Claussen
authors.forename: Anna C
authors.initials: AC
authors.lastname: Pfannenberg
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D017060:Patient Satisfaction; D049268:Positron-Emission Tomography / Q000295:instrumentation* / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D012119:Respiration; D012149:Restraint, Physical; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*; D014618:Vacuum
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18