title: 256-slice CT coronary angiography: in vivo dosimetry and technique optimization.
abstract: OBJECTIVE
  This study was undertaken to compare the different acquisition protocols available in a last-generation multislice computed tomography scanner used for cardiovascular studies, with particular attention to dosimetric aspects.
  
  
  METHODS
  Our study compared prospective and retrospective electrocardiographic-gating techniques for cardiac imaging. For each patient, we performed in vivo dose measurements, using Gafchromic film. We compared the effective dose values estimated from the experimental measurements and the dose data reported on the CT console. Image quality was also assessed.
  
  
  RESULTS
  Prospective acquisition allows for major dose savings compared to retrospective acquisition (mean effective dose, 4.5 mSv with prospective acquisition versus 27.5 mSv with retrospective acquisition). The agreement between the experimental and software-based dose estimates was excellent and showed below 10% of variation of the measured dose.
  
  
  CONCLUSIONS
  In patients with regular rhythm and a heart rate lower than 75 bpm, the prospective acquisition technique ensures adequate diagnostic results and allows for significant patient dose savings.
authors: UCO di Radiologia, Dipartimento di Scienze Mediche, Chirurgiche e della Salute, Azienda Ospedaliero-Universitaria di Trieste, Ospedale di Cattinara, strada di Fiume 447, Trieste, Italy, belgranom@gmail.com.
authors: Manuel
authors: M
authors: Belgrano
authors: Paola
authors: P
authors: Bregant
authors: Micheline Fute
authors: MF
authors: Djoguela
authors: William
authors: W
authors: Toscano
authors: Elena
authors: E
authors: Marchese
authors: Maria A
authors: MA
authors: Cova
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055424:Cardiac-Gated Imaging Techniques; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging*; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D007479:Iopamidol / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol