title: Dose levels and image quality of second-generation 128-slice dual-source coronary CT angiography in clinical routine.
abstract: OBJECTIVE
  To compare radiation exposure and image quality of second-generation 128-slice dual-source CT (DSCT) coronary angiography (cCTA) protocols.
  
  
  METHODS
  We retrospectively analyzed data from four groups with 25 patients, each examined by one of the following DSCT cCTA protocols: prospectively ECG-gated high-pitch (group 1) or sequential (group 2) acquisition, retrospectively ECG-gated acquisition in dual-energy (DECT, group 3) or dual-source (group 4) mode. CT dose index volume, dose length product, estimated radiation dose, contrast-to-noise- and signal-to-noise-ratios were compared. Subjective image quality was rated by two observers blinded to the protocols.
  
  
  RESULTS
  High-pitch DSCT showed a mean estimated radiation dose of 1.27 ± 0.62 mSv, significantly (p < 0.01) lower than sequential (2.04 ± 0.94 mSv), dual-energy (3.97 ± 1.29 mSv) or dual-source (8.11 ± 4.95 mSv) acquisition. Image noise showed no statistical difference (p > 0.91), ranging from 15.2 ± 4.4 (group 2) up to 24.5 ± 22.0 (group 4). Each protocol showed diagnostic image quality in at least 98.1 % of evaluated coronary segments without significant differences (p > 0.05).
  
  
  CONCLUSIONS
  Prospectively ECG-gated DSCT protocols enable cCTA with significant dose reduction and consistently diagnostic image quality. In patients requiring retrospectively ECG-gated DSCT for functional analysis or due to arrhythmia, dual-energy mode should be preferred over dual-source mode as it significantly decreases estimated dose without compromising image quality.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany. docwichmann@gmail.com.|Universitätsklinikum Frankfurt Am Main, Institut für Diagnostische Und Interventionelle Radiologie, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany. docwichmann@gmail.com.
authors.forename: Julian L
authors.initials: JL
authors.lastname: Wichmann
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Xiaohan
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Cranio-Maxillofacial and Plastic Facial Surgery, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Engler
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: J Matthias
authors.initials: JM
authors.lastname: Kerl
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Beeres
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Frellesen
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Luboldt
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Vogl
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Ralf W
authors.initials: RW
authors.lastname: Bauer
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lehnert
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D006801:Humans; D007089:Image Enhancement; D011829:Radiation Dosage; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Coronary computed tomography angiography; Dual-source computed tomography angiography; High-pitch spiral acquisition; Multidetector-computed tomography; Radiation dose