Influence of exposure parameters on patient dose and image noise in computed tomography

• Authors: Desislav Stoyanov , Jenia Vassileva
• Languages of publication: EN

Abstracts

EN

This work presents the results of investigation of influence of main exposure parameters on the patient dose and image noise on five clinical computed tomography units. Patient dose was determined by means of the quantity CTDIair free on air measured with pencil shaped ionization chamber. The image noise was estimated as a standard deviation of CT numbers in a 500 mm2 central region of interest in a water-equivalent phantom positioned in the centre of rotation. The alteration of tube voltage and tube current show the potential in patient dose reduction up to 40% but may deteriorate image quality and has to be carefully applied in order to optimize the clinical CT protocols taking into account the specific clinical task. This survey is essential for optimization of routine CT protocols especially for CT units without automatic exposure control systems, which are main part of CT units in Bulgaria.

Keywords

EN

Computed tomography; dose quantities; image noise; exposure parameters; optimization

• Publisher: Versita
• Journal: Polish Journal of Medical Physics And Engineering
• Year: 2009
• Volume: 15
• Issue: 4
• Pages: 215-226

Dates

published

1 - 1 - 2009

online

22 - 9 - 2010

Contributors

author

Desislav Stoyanov

• National Centre of Radiobiology and Radiation Protection, Sofia, Bulgaria

author

Jenia Vassileva

• National Centre of Radiobiology and Radiation Protection, Sofia, Bulgaria

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Identifiers

DOI

10.2478/v10013-009-0021-9