title: Readjustment of abdominal computed tomography protocols in a university hospital: impact on radiation dose.
abstract: OBJECTIVE
  To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters.
  
  
  METHODS
  Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A - 551 studies) and three months after (group B - 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDIvol per phase, mean DLP per phase, and mean DLP per scan.
  
  
  RESULTS
  A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDIvol per phase, DLP per phase and DLP per scan (p < 0.001).
  
  
  CONCLUSIONS
  The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans.
authors.affiliation: Collaborating Physicians, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Ricardo Francisco Tavares
authors.initials: RF
authors.lastname: Romano
authors.affiliation: Collaborating Physicians, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Priscila Silveira
authors.initials: PS
authors.lastname: Salvadori
authors.affiliation: Masters, Physicians Assistants, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Lucas Rios
authors.initials: LR
authors.lastname: Torres
authors.affiliation: MD, Fellow, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Elisa Almeida Sathler
authors.initials: EA
authors.lastname: Bretas
authors.affiliation: Masters, Physicians Assistants, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bekhor
authors.affiliation: PhD, MD, Radiologist, Fleury Medicina e Saúde, São Paulo, SP, Brazil.
authors.forename: Rogério Pedreschi
authors.initials: RP
authors.lastname: Caldana
authors.affiliation: Affiliate Professor, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Regina Bitelli
authors.initials: RB
authors.lastname: Medeiros
authors.affiliation: Private Docent, Associate Professor, Department of Imaging Diagnosis at Escola Paulista de Medicina - Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: D'Ippolito
keywords: Abdomen; Computed tomography; Contrast media; Radiation dose; Radiation protection