Related Experiment Video
Updated: May 13, 2025

Author Spotlight: Advancing Cardiovascular Imaging - Introducing the Spatially Weighted Calcium Score for Early Disease Detection
Published on: September 22, 2023
Ultra-high resolution photon-counting detector coronary CT minimizes overestimation bias compared to invasive
Gerald Siegfried Laux1, Moritz C Halfmann2, Larissa Kavermann1
1Department of Cardiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany.
Background:
Photon-counting detector (PCD) coronary CT angiography (CCTA) at ultra-high-resolution (UHR) is a promising tool for the detailed evaluation of the coronary arteries. However, correlation with invasive quantitative coronary angiography (QCA) has not been thoroughly investigated. We here evaluated the efficacy of UHR-CCTA against invasive QCA in patients suspected of coronary artery disease (CAD).
Methods:
Retrospectively, patients suggestive of CAD were included if they had undergone UHR-CCTA on a PCD-CT system showing coronary stenosis which clinically indicated subsequent invasive coronary angiography and no prior coronary interventions. CCTA datasets were reconstructed in 0.6 mm, 0.4 mm, and UHR 0.2 mm slice thicknesses. The extent of stenosis was compared between QCA and CCTA using univariate analysis of variance with post-hoc testing and Bland-Altman plots. Diagnostic performance was assessed based on the detection of relevant coronary stenosis (≥50 %) as confirmed by QCA.
Results:
Forty-nine patients (71 ± 9 years; 37 % male) were included. Stenosis evaluation for 103 segments revealed decreasing mean stenosis diameter with improving spatial resolution (61.4 % for 0.6 mm, 55.3 % for 0.4 mm, 50.9 % for UHR 0.2 mm; p ≤ 0.001). Bias between CCTA and QCA decreased with increasing resolution (13.2 %, limits of agreement [LoA] 30 vs. 9.4 %, 28.1 vs. 5.2 %, 23). UHR-CCTA reconstructions showed superior diagnostic accuracy and positive predictive value (PPV) for detecting relevant CAD compared to lower resolutions (61.2 vs. 61.2 % vs. 71.4 and 53.7 % vs. 53.9 vs. 61.8 %, respectively).
Conclusions:
UHR-CCTA with photon-counting detector CT demonstrated a decrease in overestimation bias and an increase in PPV.
Related Concept Videos
Imaging Studies for Cardiovascular System III: X-Ray
Definition and Purpose
An X-ray, or radiograph, is a non-invasive method that uses ionizing radiation to take images of internal structures. It is mainly used in cardiac imaging to examine the heart, lungs, and major blood vessels, aiming to identify abnormalities in the heart's size, shape, and position, such as heart failure, congenital defects, and vascular...
Computed Tomography
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...

