Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Aug 1;57(8):536-543.
doi: 10.1097/RLI.0000000000000868. Epub 2022 Mar 21.

Coronary Computed Tomography Angiography-Based Calcium Scoring: In Vitro and In Vivo Validation of a Novel Virtual Noniodine Reconstruction Algorithm on a Clinical, First-Generation Dual-Source Photon Counting-Detector System

Tilman Emrich, Gilberto Aquino  1 , U Joseph Schoepf  1 , Franziska M Braun  2 , Franka Risch  2 , Stefanie J Bette  2 , Piotr Woznicki  2 , Josua A Decker  2 , Jim O'Doherty  3 , Verena Brandt  1 , Thomas Allmendinger  4 , Tristan Nowak  4 , Bernhard Schmidt  4 , Thomas Flohr  4 , Thomas J Kroencke  2 , Christian Scheurig-Muenkler  2 , Akos Varga-Szemes  1 , Florian Schwarz  2
Affiliations

Coronary Computed Tomography Angiography-Based Calcium Scoring: In Vitro and In Vivo Validation of a Novel Virtual Noniodine Reconstruction Algorithm on a Clinical, First-Generation Dual-Source Photon Counting-Detector System

Tilman Emrich et al. Invest Radiol. .

Abstract

Purpose: The aim of this study was to evaluate coronary computed tomography angiography (CCTA)-based in vitro and in vivo coronary artery calcium scoring (CACS) using a novel virtual noniodine reconstruction (PureCalcium) on a clinical first-generation photon-counting detector-computed tomography system compared with virtual noncontrast (VNC) reconstructions and true noncontrast (TNC) acquisitions.

Materials and methods: Although CACS and CCTA are well-established techniques for the assessment of coronary artery disease, they are complementary acquisitions, translating into increased scan time and patient radiation dose. Hence, accurate CACS derived from a single CCTA acquisition would be highly desirable. In this study, CACS based on PureCalcium, VNC, and TNC, reconstructions was evaluated in a CACS phantom and in 67 patients (70 [59/80] years, 58.2% male) undergoing CCTA on a first-generation photon counting detector-computed tomography system. Coronary artery calcium scores were quantified for the 3 reconstructions and compared using Wilcoxon test. Agreement was evaluated by Pearson and Spearman correlation and Bland-Altman analysis. Classification of coronary artery calcium score categories (0, 1-10, 11-100, 101-400, and >400) was compared using Cohen κ .

Results: Phantom studies demonstrated strong agreement between CACS PureCalcium and CACS TNC (60.7 ± 90.6 vs 67.3 ± 88.3, P = 0.01, r = 0.98, intraclass correlation [ICC] = 0.98; mean bias, 6.6; limits of agreement [LoA], -39.8/26.6), whereas CACS VNC showed a significant underestimation (42.4 ± 75.3 vs 67.3 ± 88.3, P < 0.001, r = 0.94, ICC = 0.89; mean bias, 24.9; LoA, -87.1/37.2). In vivo comparison confirmed a high correlation but revealed an underestimation of CACS PureCalcium (169.3 [0.7/969.4] vs 232.2 [26.5/1112.2], P < 0.001, r = 0.97, ICC = 0.98; mean bias, -113.5; LoA, -470.2/243.2). In comparison, CACS VNC showed a similarly high correlation, but a substantially larger underestimation (24.3 [0/272.3] vs 232.2 [26.5/1112.2], P < 0.001, r = 0.97, ICC = 0.54; mean bias, -551.6; LoA, -2037.5/934.4). CACS PureCalcium showed superior agreement of CACS classification ( κ = 0.88) than CACS VNC ( κ = 0.60).

Conclusions: The accuracy of CACS quantification and classification based on PureCalcium reconstructions of CCTA outperforms CACS derived from VNC reconstructions.

PubMed Disclaimer

Conflict of interest statement

Conflicts of interest and sources of funding: U. Joseph Schoepf receives institutional research support and / or personal fees from Bayer, Bracco, Elucid Bioimaging, Guerbet, HeartFlow, and Siemens. Akos Varga-Szemes receives institutional research support and / or personal fees from Elucid Bioimaging and Siemens. Tilman Emrich received a speaker fee and travel support from Siemens Medical Solutions USA Inc. Jim O’Doherty is a employee of Siemens Medical Solutions USA Inc. Thomas Allmendinger, Tristan Nowak, Bernhard Schmidt and Thomas Flohr are employees of Siemens Healthineers

References

    1. Divakaran S, Cheezum MK, Hulten EA, et al. Use of cardiac CT and calcium scoring for detecting coronary plaque: implications on prognosis and patient management. Br J Radiol . 2015;88:20140594.
    1. Knuuti J, Wijns W, Saraste A, et al. 2019 ESC guidelines for the diagnosis and management of chronic coronary syndromes: the Task Force for the Diagnosis and Management of Chronic Coronary Syndromes of the European Society of Cardiology (ESC). Eur Heart J . 2020;41:407–477. Available at: https://doi.org/10.1093/eurheartj/ehz425 . - DOI
    1. Moss AJ, Williams MC, Newby DE, et al. The updated NICE guidelines: cardiac CT as the first-line test for coronary artery disease. Curr Cardiovasc Imaging Rep . 2017;10:15. Available at: https://pubmed.ncbi.nlm.nih.gov/28446943 .
    1. Schwarz F, Nance JWJ, Ruzsics B, et al. Quantification of coronary artery calcium on the basis of dual-energy coronary CT angiography. Radiology . 2012;264:700–707.
    1. Gassert FG, Schacky CE, Müller-Leisse C, et al. Calcium scoring using virtual non-contrast images from a dual-layer spectral detector CT: comparison to true non-contrast data and evaluation of proportionality factor in a large patient collective. Eur Radiol . 2021;31:6193–6199.