title: [Prospective electrocardiogram gated coronary 320-row area detector computed tomography angiography using low tube current scanning with full reconstruction].
abstract: BACKGROUND
  It is possible to obtain equivalent image quality and a lower radiation dose using low tube current scanning with full reconstruction as compared to usual tube current scanning with half reconstruction in a 320-row area detector computed tomography (ADCT) angiography.
  
  
  METHODS
  Of 589 patient underwent coronary CT angiography (CCTA), 11 patients with (RR-PQ) ≥1069 ms were enrolled. In those patients, low tube current (50% mA) scanning with full or half reconstruction were performed. As a control, 11 patients with matched pairs of tube voltage, BMI and heart rate who underwent usual scanning with half reconstruction (100% mA with half reconstruction) were selected. Standard deviation of the CT value (SD) was measured in aorta (Ao), left atrium (LA) and left ventricle (LV), and extended dose-length products (DLP.e) were calculated.
  
  
  RESULTS
  Significant motion artifact was not observed in any patients. SD of 50% mA with half reconstruction, 50% mA with full reconstruction, and 100% mA with half reconstruction were 28.1±2.6, 20.3±1.9, 20.7±2.5 HU in Ao, 34.4±4.4, 24.9±2.8, 24.9±3.1 HU in LA, and 29.7±2.3, 21.7±1.9, 22.1±2.3 HU in LV, respectively. There were not significant differences between 50% mA with full reconstruction and 100% mA with half reconstruction, but there were significant differences between 50% mA with half reconstruction and 50% mA with full reconstruction in all sites. The DLP.e of 50% mA scanning (74.1±21.8 mGy·cm) was significantly lower than 100% mA scanning (161.9±28.9 mGy·cm).
  
  
  CONCLUSIONS
  CCTA with lower radiation dose and equivalent image quality can be obtained by ADCT using 50% mA scanning with full reconstruction in patients with (RR-PQ) ≥1069 ms.
authors.affiliation: Department of Radiological Technology, Takase Clinic, Japan.
authors.forename: Tomonari
authors.initials: T
authors.lastname: Sano
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Matsutani
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kondo
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Fujimoto
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takamura
authors.forename: Takako
authors.initials: T
authors.lastname: Sekine
authors.forename: Takehiro
authors.initials: T
authors.lastname: Arai
authors.forename: Hitomi
authors.initials: H
authors.lastname: Morita
authors.forename: Shinichi
authors.initials: S
authors.lastname: Takase
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*