title: Low-dose high-pitch CT angiography of the supraaortic arteries using sinogram-affirmed iterative reconstruction.
abstract: OBJECTIVE
  To prospectively evaluate image quality and radiation dose using a low-dose computed tomography angiography protocol and iterative image reconstruction for high-pitch dual-source CT-angiography (DSCTA) of the supraaortic arteries.
  
  
  METHODS
  DSCTA was performed in 42 patients, using either 120 kVp tube voltage, 120 mAS tube current, 2.4 pitch and filtered back projection, or 100 kVp tube voltage, 100 mAs tube current, 3.2 pitch, and sinogram affirmed iterative reconstruction. Measurements of vessel attenuation, of the contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were performed to objectively evaluate image quality. Two readers evaluated subjective image quality and image noise, using a four-point scale. Effective dose was used to compare the differences in radiation dose.
  
  
  RESULTS
  Low-dose protocol application showed significantly higher vessel opacification (p = 0.013), and non-significantly higher CNR and SNR values. There was no difference in the subjective image quality and image noise reading between the protocols. Effective dose was significantly lower using the low-dose protocol (1.29 ± 0.21 mSv vs. 2.92 ± 0.72 mSv; p < 0.001).
  
  
  CONCLUSIONS
  The combined use of reduced tube voltage, reduced tube current, and iterative reconstruction reduces radiation dose by 55.4% in high-pitch DSCTA of the supraaortic arteries without impairment of image quality.
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Dietrich
authors.initials: D
authors.lastname: Beitzke
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Richard
authors.initials: R
authors.lastname: Nolz
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Unterhumer
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Christina
authors.initials: C
authors.lastname: Plank
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Weber
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Schernthaner
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Veronika
authors.initials: V
authors.lastname: Schöpf
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Wolf
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Loewe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods*; D001158:Arteries / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011829:Radiation Dosage; D011877:Radionuclide Imaging; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*