Assessment of task-based image quality for abdominal CT protocols linked with national diagnostic reference levels.

Details

Serval ID
serval:BIB_6B10F810AE30
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Assessment of task-based image quality for abdominal CT protocols linked with national diagnostic reference levels.
Journal
European radiology
Author(s)
Viry A., Aberle C., Lima T., Treier R., Schindera S.T., Verdun F.R., Racine D.
ISSN
1432-1084 (Electronic)
ISSN-L
0938-7994
Publication state
Published
Issued date
02/2022
Peer-reviewed
Oui
Volume
32
Number
2
Pages
1227-1237
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Abstract
To assess task-based image quality for two abdominal protocols on various CT scanners. To establish a relationship between diagnostic reference levels (DRLs) and task-based image quality.
A protocol for the detection of focal liver lesions was used to scan an anthropomorphic abdominal phantom containing 8- and 5-mm low-contrast (20 HU) spheres at five CTDI <sub>vol</sub> levels (4, 8, 12, 16, and 20 mGy) on 12 CTs. Another phantom with high-contrast calcium targets (200 HU) was scanned at 2, 4, 6, 10, and 15 mGy using a renal stones protocol on the same CTs. To assess the detectability, a channelized Hotelling observer was used for low-contrast targets and a non-prewhitening observer with an eye filter was used for high contrast targets. The area under the ROC curve and signal to noise ratio were used as figures of merit.
For the detection of 8-mm spheres, the image quality reached a high level (mean AUC over all CTs higher than 0.95) at 11 mGy. For the detection of 5-mm spheres, the AUC never reached a high level of image quality. Variability between CTs was found, especially at low dose levels. For the search of renal stones, the AUC was nearly maximal even for the lowest dose level.
Comparable task-based image quality cannot be reached at the same dose level on all CT scanners. This variability implies the need for scanner-specific dose optimization.
• There is an image quality variability for subtle low-contrast lesion detection in the clinically used dose range. • Diagnostic reference levels were linked with task-based image quality metrics. • There is a need for specific dose optimization for each CT scanner and clinical protocol.
Keywords
Algorithms, Diagnostic Reference Levels, Humans, Phantoms, Imaging, Radiation Dosage, Signal-To-Noise Ratio, Tomography Scanners, X-Ray Computed, Tomography, X-Ray Computed, Diagnostic reference levels, Multidetector computed tomography, Radiation protection
Pubmed
Web of science
Open Access
Yes
Create date
06/08/2021 12:14
Last modification date
18/03/2022 7:34
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