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Pediatric Radiology

Published in:

01-06-2013 | Original Article

Effect of vertical positioning on organ dose, image noise and contrast in pediatric chest CT—phantom study

Authors: Touko Kaasalainen, Kirsi Palmu, Anniina Lampinen, Mika Kortesniemi

Published in: Pediatric Radiology | Issue 6/2013

Abstract

Background

CT optimization has a special importance in children. Smaller body size accentuates the importance of patient positioning affecting both radiation dose and image quality.

Objective

To determine the effect of vertical positioning on organ dose, image noise and contrast in pediatric chest CT examination.

Materials and methods

Chest scans of a pediatric 5-year anthropomorphic phantom were performed in different vertical positions (−6 cm to +5.4 cm) with a 64-slice CT scanner. Organ doses were measured with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Image noise and contrast were determined from the CT number histograms corresponding to different tissues.

Results

Significant changes in organ doses resulting from vertical positioning were observed, especially in radiosensitive anterior organs. The breast dose increased up to 16% and the thyroid dose up to 24% in lower positions. The noise was increased up to 45% relative to the centre position in the highest and lowest vertical positions, with a particular increase observed on the anterior and posterior sides, respectively. Off-centering also affected measured image contrast.

Conclusion

Vertical off-centering markedly affects organ doses and measured image-quality parameters in pediatric chest CT examination. Special attention should be given to correct patient centering when preparing patients for CT scans, especially when imaging children.

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Title: Effect of vertical positioning on organ dose, image noise and contrast in pediatric chest CT—phantom study
Authors: Touko Kaasalainen
Kirsi Palmu
Anniina Lampinen
Mika Kortesniemi
Publication date: 01-06-2013
Publisher: Springer-Verlag
Published in: Pediatric Radiology / Issue 6/2013
Print ISSN: 0301-0449
Electronic ISSN: 1432-1998
DOI: https://doi.org/10.1007/s00247-012-2611-z

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Effect of vertical positioning on organ dose, image noise and contrast in pediatric chest CT—phantom study

Abstract

Background

Objective

Materials and methods

Results

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Objective

Materials and methods

Results

Conclusion

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