<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">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 <italic>CTDIair</italic> 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.</abstract>

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.

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

National Centre of Radiobiology and Radiation Protection, Sofia, Bulgaria

Polish Journal of Medical Physics and Engineering

This work presents the results of investigation of influence of main exposure parameters on the patient dose and image noise on five clinical computed...

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

Published Online: Sep 22, 2010

Page range: 215 - 226

DOI: https://doi.org/10.2478/v10013-009-0021-9

Keywords
Computed tomography, dose quantities, image noise, exposure parameters, optimization

This content is open access.

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

Published Online: Sep 22, 2010

Page range: 215 - 226

DOI: https://doi.org/10.2478/v10013-009-0021-9

KeywordsComputed tomography, dose quantities, image noise, exposure parameters, optimization

This content is open access.

Keywords
Computed tomography, dose quantities, image noise, exposure parameters, optimization