title: Use of an automatic recording system for CT doses: evaluation of the impact of iterative reconstruction on radiation exposure in clinical practice.
abstract: OBJECTIVE
  Despite the obligatory recording of doses administered to patients during CT scans, this data is not easily accessible. The objective of this study was to implement and validate a computerised automated dose-recording system for CT scans, for a single radiology department.
  
  
  METHODS
  Every patient undergoing a CT scan in our department over a one-year period was included in the study. The CT scanner was upgraded after eight months (installation of iterative reconstruction and choice of an additional voltage of 100 kV). The system recorded, from DICOM image headers, the patient data and technical acquisition parameters. The statistical analysis compared the dose length products (DLP) before and after the upgrade, and compared them with the diagnostic reference levels (DRL).
  
  
  RESULTS
  Four thousand seven hundred and ninety-five CT scans were included (2141 before the upgrade and 2654 after). For all of the acquisition protocols tested, there was a reduction in DLP after the upgrade. The mean reduction was 30%, with a range of 17% to 44% depending on the protocol. After the upgrade, all of the mean DLPs were under the DRL thresholds (P<0.0001).
  
  
  CONCLUSIONS
  The proposed tool enabled systematic recording of the doses of radiation used in CT scans. It confirmed the significant reduction in the dose resulting from the implementation of iterative reconstruction, and enabled an exhaustive and rapid control of the respect of DRLs.
authors.affiliation: Service de radiologie, hôpital de la Croix-Rousse, 103, Grande-Rue-de-la-Croix-Rousse, 69004 Lyon, France. Electronic address: lauranne.burckel@yahoo.com.
authors.forename: L-A
authors.initials: LA
authors.lastname: Burckel
authors.affiliation: PSRPM Imagerie GH Sud, service de physique médicale et radioprotection, centre hospitalier Lyon Sud, Bat 3B-1(er) étage, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite, France.
authors.forename: D
authors.initials: D
authors.lastname: Defez
authors.affiliation: Service de radiologie, hôpital de la Croix-Rousse, 103, Grande-Rue-de-la-Croix-Rousse, 69004 Lyon, France.
authors.forename: P F
authors.initials: PF
authors.lastname: Chaillot
authors.affiliation: Inserm U1044, CREATIS, CNRS UMR5220, INSA-Lyon, université Lyon 1, service de radiologie, hôpital Louis-Pradel, 28, avenue du Doyen-Jean-Line, 69500 Bron, France.
authors.forename: P
authors.initials: P
authors.lastname: Douek
authors.affiliation: Service de radiologie, hôpital de la Croix-Rousse, 103, Grande-Rue-de-la-Croix-Rousse, 69004 Lyon, France; Inserm U1044, CREATIS, CNRS UMR5220, INSA-Lyon, université Lyon 1, service de radiologie, hôpital Louis-Pradel, 28, avenue du Doyen-Jean-Line, 69500 Bron, France.
authors.forename: L
authors.initials: L
authors.lastname: Boussel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D016347:Medical Records Systems, Computerized; D008875:Middle Aged; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011872:Radiology Department, Hospital; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
keywords: CT scan; Dose; Iterative reconstruction; Medical computer application; Patient safety