title: A multicenter evaluation of commercial attenuation compensation techniques in cardiac SPECT using phantom models.
abstract: BACKGROUND
  Our goal was to evaluate the ability of current commercially available attenuation compensation (AC) techniques to correct for the effects of attenuation, scatter, and loss of resolution with depth, in a series of standardized phantom experiments.
  
  
  RESULTS
  The following systems were evaluated: Hawkeye (GE Medical Systems), Profile (Siemens Medical Systems), Vantage Pro (ADAC Laboratories), TAC (SMV America), M-STEP (University of Michigan, Ann Arbor), TransAct (Elscint), Beacon (Marconi Systems), and PET Advance (GE Medical Systems). Studies were performed with the use of normal and ischemic myocardium in air and with technetium 99m or fluorine 18 in torso phantoms. There was considerable variation in the uniformity of short-axis slices and defect contrast for images acquired in air (no AC). AC improved the uniformity of activity throughout normal myocardium. A simulated hot liver resulted in severe artifacts and was only partially corrected by many systems. A high-quality attenuation map appears to be an important determinant of image quality. No system produced AC images of comparable quality to those obtained in the absence of scatter/attenuating media.
  
  
  CONCLUSIONS
  There are significant differences in the ability of commercial AC systems to reduce artifacts due to attenuation and scatter. These differences are partly the result of non-AC factors (collimation, orbit, etc). In general, systems that generated high-quality attenuation maps yielded the best results.
authors.affiliation: Mayo Clinic, Core Laboratory, Rochester, Minnesota 55905, USA. mkoconner@mayo.edu
authors.forename: Michael K
authors.initials: MK
authors.lastname: O'connor
authors.forename: Brad
authors.initials: B
authors.lastname: Kemp
authors.forename: Frank
authors.initials: F
authors.lastname: Anstett
authors.forename: Paul
authors.initials: P
authors.lastname: Christian
authors.forename: Edward P
authors.initials: EP
authors.lastname: Ficaro
authors.forename: Eric
authors.initials: E
authors.lastname: Frey
authors.forename: Mark
authors.initials: M
authors.lastname: Jacobs
authors.forename: James N
authors.initials: JN
authors.lastname: Kritzman
authors.forename: Robert A
authors.initials: RA
authors.lastname: Pooley
authors.forename: Michael
authors.initials: M
authors.lastname: Wilk
mesh_terms: D000465:Algorithms; D003132:Commerce / Q000592:standards*; D005069:Evaluation Studies as Topic; D006331:Heart Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000592:standards; D019047:Phantoms, Imaging / Q000592:standards*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012984:Software / Q000592:standards; D014055:Tomography, Emission-Computed / Q000592:standards; D015899:Tomography, Emission-Computed, Single-Photon / Q000592:standards*