title: Superiority of synchrony of 256-slice cone beam computed tomography for acquiring pulsating objects. Comparison with conventional multislice computed tomography.
abstract: OBJECTIVE
  A prototype 256-slice cone beam computed tomography (CT) provides complete volumetric data within a single gantry rotation (1 s/rotation) with 0.5 mm slice-thickness.
  
  
  METHODS
  Calcified phantoms (200-400 HU) were attached to the balloon of a pulsating phantom and moved at a rate of 5-90/min. Acquisition was performed during one to-and-fro motion at each pulsation rate without electrocardiogram (ECG)-gating. Each period was divided into 10 phases, and compared to conventional multislice CT scanning without ECG-gating.
  
  
  RESULTS
  At 5-20/min, the configuration of calcified phantoms continued to the through-plane without gaps. At 60/min, duplicated calcified phantoms at end-systole and end-diastole were observed without motion. At 90/min, motion could be observed without gaps but was more blurred, and total calcified volume, Agatston scores, mean and max CT values of three phantoms were almost equal compared with those at static state. However, at 60/min, total calcified volume, scores, mean and max CT values of three phantoms were decreased to 64%, 37%, 80% and 56%, respectively, compared with those at static state. In multislice CT, even at lower rates, there were gaps in the through-plane. At 60/min, total calcified volume, scores, mean and max CT values of three phantoms were decreased to only 8%, 3%, 79% and 53%, respectively, compared with static state.
  
  
  CONCLUSIONS
  This new prototype's unique character (synchrony) enables the acquisition of pulsating objects. These can be acquired without gaps in the through-plane even in the absence of ECG-gating. However, its present temporal resolution only permits accurate quantitative evaluation of calcium up to 20/min.
authors.forename: Nobusada
authors.initials: N
authors.lastname: Funabashi
authors.forename: Naoko
authors.initials: N
authors.lastname: Mizuno
authors.forename: Katsuya
authors.initials: K
authors.lastname: Yoshida
authors.forename: Takanori
authors.initials: T
authors.lastname: Tsunoo
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Mori
authors.forename: Shuji
authors.initials: S
authors.lastname: Tanada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Endo
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
mesh_terms: D004562:Electrocardiography; D007091:Image Processing, Computer-Assisted; D008955:Models, Cardiovascular; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods