title: A novel respiratory gating method for oncologic positron emission tomography based on bioimpedance approach.
abstract: OBJECTIVE
  Respiratory motion causes loss of image quality and inaccuracy of quantification in oncologic positron emission tomography (PET) imaging. This study introduces a bioimpedance-based gating method for compensation of respiratory motion artefacts.
  
  
  METHODS
  The bioimpedance-based respiratory gating method was studied parallel to a clinically used respiratory gating method [Real-time Position Management by Varian Medical Systems] in 4D PET/CT acquisition of 9 oncologic patients. The quantitative analysis consisted of the evaluation of tumour SUVpeak, SUVmax and volume. Additionally, target-to-background ratios as well as motion in cranial-caudal and anterior-posterior directions were measured. The evaluation was performed with amplitude- and time-based gating using averaged attenuation correction maps.
  
  
  RESULTS
  Bioimpedance gating resulted in 17.7-18.9 % increase in mean SUVpeak and 20.0-21.4 % decrease in mean volume compared to non-gated images. The maximum motion measured from the bioimpedance-gated images was 19 mm in cranial-caudal direction and 9 mm in anterior-posterior direction.
  
  
  CONCLUSIONS
  Bioimpedance-based respiratory gating compensates the adverse effects of motion in oncologic PET imaging.
authors: Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland, tuomas.koivumaki@kuh.fi.
authors: Tuomas
authors: T
authors: Koivumäki
authors: Jarmo
authors: J
authors: Teuho
authors: Mika
authors: M
authors: Teräs
authors: Marko
authors: M
authors: Vauhkonen
authors: Mikko A
authors: MA
authors: Hakulinen
mesh_terms: D000368:Aged; D016477:Artifacts; D017097:Electric Impedance; D005260:Female; D019788:Fluorodeoxyglucose F18; D056973:Four-Dimensional Computed Tomography / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D009038:Motion; D064847:Multimodal Imaging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012119:Respiration; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18