Radiological Physics and Technology

, Volume 11, Issue 2, pp 184–191 | Cite as

Dosimetric changes with computed tomography automatic tube-current modulation techniques

  • Sofia Spampinato
  • Anna Maria Gueli
  • Pietro Milone
  • Luigi Angelo Raffaele


The study is aimed at a verification of dose changes for a computed tomography automatic tube-current modulation (ATCM) technique. For this purpose, anthropomorphic phantom and Gafchromic® XR-QA2 films were used. Radiochromic films were cut according to the shape of two thorax regions. The ATCM algorithm is based on noise index (NI) and three exam protocols with different NI were chosen, of which one was a reference. Results were compared with dose values displayed by the console and with Poisson statistics. The information obtained with radiochromic films has been normalized with respect to the NI reference value to compare dose percentage variations. Results showed that, on average, the information reported by the CT console and calculated values coincide with measurements. The study allowed verification of the dose information reported by the CT console for an ATCM technique. Although this evaluation represents an estimate, the method can be a starting point for further studies.


Noise index Radiochromic films CTDI DLP Anthropomorphic phantom 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Statement of human rights

This article does not contain any studies with human participants performed.

Statement of animal rights

This article does not contain any studies with animals performed.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Japanese Society of Radiological Technology and Japan Society of Medical Physics 2018

Authors and Affiliations

  • Sofia Spampinato
    • 1
    • 2
    • 4
  • Anna Maria Gueli
    • 1
    • 2
  • Pietro Milone
    • 2
    • 3
  • Luigi Angelo Raffaele
    • 1
    • 2
    • 3
  1. 1.PH3DRA Laboratories (PHysics for Dating Diagnostic Dosimetry Research and Applications), Dipartimento di Fisica e AstronomiaUniversità di Catania and INFN-CataniaCataniaItaly
  2. 2.Scuola di Specializzazione in Fisica Medica, Dipartimento di Scienze mediche chirurgiche e tecnologie avanzate “G. F. Ingrassia”, Scuola Facoltà di MedicinaCataniaItaly
  3. 3.Unità Operativa Complessa di Radiodiagnostica e RadioterapiaAzienda Ospedaliero-Universitaria Policlinico di Catania, P. O. Gaspare RodolicoCataniaItaly
  4. 4.Department of OncologyAarhus University HospitalAarhusDenmark

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