title: Organ Doses and Radiation Risk of Computed Tomographic Coronary Angiography in a Clinical Patient Population: How Do Low-Dose Acquisition Modes Compare?
abstract: OBJECTIVE
  To compare the organ doses and lifetime-attributable risk of cancer for electrocardiogram-triggered sequential and high-pitch helical scanning in a clinical patient population.
  
  
  METHODS
  Phantom thermoluminiscence dosimeter measurements were used as a model for the organ dose assessment of 314 individual patients who underwent coronary computed tomographic angiography. Patient-specific lifetime-attributable cancer risks were calculated.
  
  
  RESULTS
  Phantom measurements showed that heart rate had a significant influence on the delivered radiation exposure in sequential mode, and calcium scoring and contrast bolus tracking scans make a nonnegligible contribution to patients' dose. Therefore, they should be taken into account for patients' organ dose estimations. Median cancer induction risks are low, with 0.008% (0.0016%) and 0.022% (0.056%) for high-pitch and sequential scanning for men (women), respectively.
  
  
  CONCLUSIONS
  The use of high-pitch helical scanning leads to 65% and 72% lower lifetime-attributable risk values for men and women, respectively, compared with sequential scanning.
authors.affiliation: From the *Department of Basic Medical Sciences, Ghent University, Ghent, Belgium; and †Department of Radiology, University Hospital Ghent, Ghent, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Eloot
authors.forename: Daniel
authors.initials: D
authors.lastname: Devos
authors.forename: Stephen
authors.initials: S
authors.lastname: Van Meerbeeck
authors.forename: Eric
authors.initials: E
authors.lastname: Achten
authors.forename: Koenraad
authors.initials: K
authors.lastname: Verstraete
authors.forename: Hubert
authors.initials: H
authors.lastname: Thierens
authors.forename: Klaus
authors.initials: K
authors.lastname: Bacher
mesh_terms: D055424:Cardiac-Gated Imaging Techniques; D015331:Cohort Studies; D017023:Coronary Angiography / Q000379:methods*; D005260:Female; D006321:Heart; D006339:Heart Rate; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D012306:Risk; D013819:Thermoluminescent Dosimetry / Q000706:statistics & numerical data; D036542:Tomography, Spiral Computed / Q000379:methods*