Objective comparison of high-contrast spatial resolution and low-contrast detectability for various clinical protocols on multiple CT scanners.

Details

Serval ID
serval:BIB_BAA0EE84367D
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Objective comparison of high-contrast spatial resolution and low-contrast detectability for various clinical protocols on multiple CT scanners.
Journal
Medical physics
Author(s)
Racine D., Viry A., Becce F., Schmidt S., Ba A., Bochud F.O., Edyvean S., Schegerer A., Verdun F.R.
ISSN
2473-4209 (Electronic)
ISSN-L
0094-2405
Publication state
Published
Issued date
09/2017
Peer-reviewed
Oui
Volume
44
Number
9
Pages
e153-e163
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Abstract
We sought to compare objectively computed tomography (CT) scanner performance for three clinically relevant protocols using a task-based image quality assessment method in order to assess the potential for radiation dose reduction.
Four CT scanners released between 2003 and 2007 by different manufacturers were compared with four CT scanners released between 2012 and 2014 by the same manufacturers using ideal linear model observers (MO): prewhitening (PW) MO and channelized Hotelling (CHO) MO with Laguerre-Gauss channels for high-contrast spatial resolution and low-contrast detectability (LCD) performance, respectively. High-contrast spatial resolution was assessed using a custom-made phantom that enabled the computation of the target transfer function (TTF) and noise power spectrum (NPS). Low-contrast detectability was assessed using a commercially available anthropomorphic abdominal phantom providing equivalent diameters of 24, 29.6, and 34.6 cm. Three protocols were reviewed: a head (trauma) and an abdominal (urinary stones) protocol were applied to assess high-contrast spatial resolution performance; and another abdominal (focal liver lesions) protocol was applied for LCD. The liver protocol was tested using fixed and modulated tube currents. The PW MO was proposed for assessing high-contrast detectability performance of the various CT scanners.
Compared with older generation CT scanners, three newer systems displayed significant improvements in high-contrast detectability over that of their predecessors. A fourth, newer system had lower performance. The CHO MO was appropriate for assessing LCD performance and revealed that an excellent level of image quality could be obtained with newer scanners at significantly lower dose levels.
This study shows that MO can objectively benchmark CT scanners using a task-based image quality method, thus helping to estimate the potential for further dose reductions offered by the latest systems. Such an approach may be useful for adequately and quantitatively comparing clinically relevant image quality among various scanners.
Keywords
Clinical Protocols, Humans, Phantoms, Imaging, Radiation Dosage, Tomography Scanners, X-Ray Computed, Tomography, X-Ray Computed, computed tomography, high-contrast spatial resolution, image quality, low-contrast detectability, model observers
Pubmed
Web of science
Open Access
Yes
Create date
19/09/2017 10:48
Last modification date
20/08/2019 15:28
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