title: A method of predicting the image noise in paediatric multi-slice computed tomography images.
abstract: The purpose of this study was to develop an equation with which to determine the tube current to be used in order to obtain a certain image noise level for differently sized children undergoing multi-slice computed tomography examination. The relationship between image noise and detector dose for different examination protocols was established for a LightSpeed Ultra, an eight slice CT from GEMS, using homogeneous water phantoms of different sizes. Three different anatomical areas (head, thorax and abdomen) were studied in 111 patients between 0 and 17 y of age. The mean ratio between the calculated and the measured noise in patient images was established for the different areas. Head examinations showed the best correlation (measured-to-calculated noise ratio = 1.01). In the thorax, the calculated noise was generally higher than the measured noise (ratio = 0.74), and in the abdomen, the opposite result was found (ratio = 1.20).
authors.affiliation: Department of Radiation Physics, Sahlgrenska University Hospital, SE-413 45 Göteborg, Sweden. kerstin.ledenius@vgregion.se
authors.forename: K
authors.initials: K
authors.lastname: Ledenius
authors.forename: M
authors.initials: M
authors.lastname: Gustavsson
authors.forename: S
authors.initials: S
authors.lastname: Johansson
authors.forename: F
authors.initials: F
authors.lastname: Stålhammar
authors.forename: J
authors.initials: J
authors.lastname: Söderberg
authors.forename: L M
authors.initials: LM
authors.lastname: Wiklund
authors.forename: A
authors.initials: A
authors.lastname: Thilander Klang
mesh_terms: D016477:Artifacts; D006257:Head / Q000000981:diagnostic imaging; D006801:Humans; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011860:Radiography, Abdominal / Q000379:methods; D013902:Radiography, Thoracic / Q000379:methods; D015898:Tomography Scanners, X-Ray Computed; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water