title: Potential for radiation dose savings in abdominal and chest CT using automatic tube voltage selection in combination with automatic tube current modulation.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the simultaneous use of automatic tube current modulation (ATCM) and automatic tube voltage selection (ATVS) for abdominal and chest CT examinations regarding radiation dose reduction and image quality.
  
  
  METHODS
  We enrolled 617 patients who all underwent contrast-enhanced chest or abdominal CT and divided them into two groups. In group A, 317 patients who underwent CT with only ATCM and a fixed body mass index-adjusted tube voltage (120 kV or 100 kV) were enrolled. In group B, both ATCM and ATVS were used. Image attenuation and noise were measured in different anatomic regions.
  
  
  RESULTS
  The mean contrast-to-noise ratio and the signal-to-noise ratio of abdomen and chest CT was higher in group B compared with group A (p < 0.0001). In total, the effective radiation doses for abdomen and chest CT examinations were significantly reduced in group B by 18% compared with group A (p < 0.0001). When only examining those who benefited from the ATVS tool, a dose reduction of 35% for chest CT and 42% for abdomen CT could be achieved (p < 0.0001 for each).
  
  
  CONCLUSIONS
  The simultaneous use of ATVS and ATCM enables significant radiation dose reduction in abdominal and thoracic contrast-enhanced CT examinations compared with the use of ATCM alone.
authors: 1 Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany.
authors: Caroline
authors: C
authors: Mayer
authors: Mathias
authors: M
authors: Meyer
authors: Christian
authors: C
authors: Fink
authors: Bernhard
authors: B
authors: Schmidt
authors: Martin
authors: M
authors: Sedlmair
authors: Stefan O
authors: SO
authors: Schoenberg
authors: Thomas
authors: T
authors: Henzler
mesh_terms: D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011860:Radiography, Abdominal; D013902:Radiography, Thoracic; D011874:Radiometry; D012189:Retrospective Studies; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*
chemical_list: D003287:Contrast Media
keywords: CT; automatic tube current modulation; automatic tube voltage selection; image quality; radiation dose reduction