Coronary calcium scoring using virtual non-contrast reconstructions on a dual-layer spectral CT system: Feasibility in the clinical practice

I L Langenbach; H Wienemann; K Klein; J E Scholtz; L Pennig; E Langzam; G Pahn; J A Holz; D Maintz; C P Naehle; M C Langenbach

doi:10.1016/j.ejrad.2022.110681

Coronary calcium scoring using virtual non-contrast reconstructions on a dual-layer spectral CT system: Feasibility in the clinical practice

Eur J Radiol. 2023 Feb:159:110681. doi: 10.1016/j.ejrad.2022.110681. Epub 2022 Dec 26.

Authors

I L Langenbach¹, H Wienemann², K Klein³, J E Scholtz⁴, L Pennig³, E Langzam⁵, G Pahn⁶, J A Holz⁷, D Maintz³, C P Naehle⁸, M C Langenbach⁹

Affiliations

¹ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany; Cardiovascular Imaging Research Center, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. Electronic address: ibreidert@mgh.harvard.edu.
² Clinic III for Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.
³ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.
⁴ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Frankfurt, University of Frankfurt, Frankfurt, Germany.
⁵ Philips Healthcare, Best, the Netherlands.
⁶ Philips CT Clinical Science, Hamburg, Germany.
⁷ Department of Radiation Oncology, University Hospital Bonn, University of Bonn, Bonn, Germany.
⁸ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany; Radiologische Allianz, Hamburg, Germany.
⁹ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany; Cardiovascular Imaging Research Center, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.

PMID: 36592582
DOI: 10.1016/j.ejrad.2022.110681

Abstract

Purpose: To evaluate the clinical applicability of a prototype virtual non-contrast (VNC) reconstruction algorithm based on coronary CT angiography (cCTA) to assess calcified coronary plaques by calcium scoring (CACS).

Methods: Eighty consecutive patients suspected of coronary artery disease were retrospectively included. All patients underwent a cardiac CT using a dual-layer spectral-detector CT system. The standardized acquisition protocol included unenhanced CACS and cCTA. Datasets were acquired using 120 keV. VNC-reconstructions were calculated from the cCTA images at 2.5 mm (VNC group 1), 2.5 of 0.9 mm (group 2), and 0.9 mm (group 3) slice thickness. We compared the Agatston score and Coronary Artery Calcium Data and Reporting System (CAC-DRS) of all VNC reconstructions with the true non-contrast (TNC)-dataset as the gold standard.

Results: In total, 73 patients were evaluated. Fifty patients (68.5 %) had a CACS > 0 based on TNC. We found a significant difference in the Agatston score comparing all VNC-reconstructions (1: 1.35, 2: 3.7, 3: 10.4) with the TNC dataset (3.8) (p < 0.001). Correlation analysis of the datasets showed an excellent correlation of the TNC results with the different VNC-reconstructions (r = 0.904-0.974, p < 0.001) with a slope of 1.89-2.53. Mean differences and limits of agreement by Bland-Altman analysis between TNC and group 1 were 83 and -196 to 362, respectively. By using the VNC-reconstructions, in group 1 23 patients (31.5 %), in group 2 10 (13.7 %), and in group 3 23 (31.5 %) were reclassified according to CAC-DRS compared to TNC. Classification according to CAC-DRS revealed a significant difference between TNC and group 1 (p = 0.024) and no significance compared to groups 2 and 3 (p = 0.670 and 0.273).

Conclusion: The investigated VNC reconstruction algorithm of routine cCTA allows the detection and evaluation of coronary calcium burden without the requirement for an additional acquisition of an unenhanced CT scan for CACS and, therefore, a reduction of radiation exposure.

Keywords: Cardiac imaging techniques; Contrast media; Coronary artery disease; Radiation dosage; Tomography; X-ray computed.

MeSH terms

Calcium* / analysis
Coronary Angiography / methods
Feasibility Studies
Humans
Retrospective Studies
Tomography, X-Ray Computed* / methods

Substances

Calcium