A multi-institutional assessment of low-dose protocols in chest computed tomography: Dose and image quality
Tonkopi, Elena; Tetteh, Mercy Afadzi; Gunn, Catherine; Ashraf, Haseem; Rusten, Sigrid Lia; Safi, Perkhah; Tinsoe, Nora Suu; Colford, Kylie; Ouellet, Olivia; Naimi, Salma; Johansen, Safora
Peer reviewed, Journal article
Published version
Permanent lenke
https://hdl.handle.net/11250/3145012Utgivelsesdato
2024Metadata
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Originalversjon
10.1177/20584601241228220http://dx.doi.org/10.1177/20584601241228220
Sammendrag
Background: Low-dose CT (LDCT) chest protocols have widespread clinical applications for many indications; as a result, there is a need for protocol assessment prior to standardization. Dalhousie University and Oslo Metropolitan University have a formally established cooperative relationship.
Purpose: The purpose is to assess radiation dose and image quality for LDCT chest protocols in seven different hospital locations in Norway and Canada.
Material and methods: Retrospective dosimetry data, volumetric CT dose index (CTDIvol), and dose length product (DLP) from 240 average-sized patients as well as CT protocol parameters were included in the survey. Effective dose (ED) and size-specific dose estimate (SSDE) were calculated for each examination. For a quantitative image quality analysis, noise, CT number, and signal-to-noise ratio (SNR) were determined for three regions in the chest. The contrast-to-noise ratio (CNR) was calculated for lung parenchyma in comparison to the subcutaneous fat. Differences in dose and image quality were evaluated by a single-factor ANOVA test. A two-sample t-test was performed to determine differences in means between individual scanners.
Results: The ANOVA test revealed significant differences (p < .05) in dose values for all scanners, including identical scanner models. Statistically significant differences (p < .05) were determined in mean values of the SNR distributions between the scanners in all three measured regions in the chest, as well as the CNR values.
Conclusion: The observed variations in dose and image quality measurements, even within the same hospitals and between identical scanner models, indicate a potential for protocol optimization in the involved hospitals in both countries.