Influence of virtual monoenergetic reconstructions on coronary CT angiography-based fractional flow reserve with photon-counting detector CT: intra-individual comparison with energy-integrating detector CT

Abstract: Objectives
This study aimed to assess the impact of the photon-counting detector (PCD)-CT-based virtual monoenergetic image (VMI) reconstruction keV levels on CT-based fractional flow reserve (CT-FFR), compared to the energy-integrating detector (EID)-CT.

Methods
Patients undergoing clinically indicated coronary CT angiography (CCTA) on an EID-CT were prospectively enrolled for a research CCTA on a PCD-CT within 30 days. PCD-CT datasets were reconstructed at VMI levels of 45, 55, 70, and 90 keV. CT-FFR was obtained semiautomatically using an on-site machine learning algorithm by two readers. CT-FFR ≤ 0.80 was considered hemodynamically significant.

Results
A total of 20 patients (63.3 ± 8.8 years; 13 men (65%) were included. Median CT-FFR values in the per-vessel analysis for PCD-CT scans were 0.86 (0.81–0.92) for 45 keV, 0.87 (0.80–0.93) for 55 keV, 0.85 (0.79–0.92) for 70 keV and 0.82 (0.76–0.89) for 90 keV, and 0.86 (0.71–0.93) for EID-CT. Comparison among different VMIs showed significant differences only for 45 vs. 90 keV (p < 0.001), and 55 vs. 90 keV (p < 0.001). No significant differences were found in the pairwise comparison between any VMI and EID-CT (all p > 0.05). PCD-CT at 70 keV showed the highest correlation (r = 0.83, p < 0.001), agreement (ICC: 0.90 (0.84–0.94)), and the lowest bias (mean bias −0.01; limits of agreement, 0.84/0.94) when compared to EID-CT.

Conclusion
VMI reconstructions showed significant influence on CT-FFR values only at the extreme levels of the spectrum, while no significant differences were found in comparison with EID-CT. VMI at 70 keV demonstrates the highest correlation and agreement, with the lowest bias compared to EID-CT

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Insights into imaging. - 16, 1 (2025) , 36, ISSN: 1869-4101

Classification and Topics

• Classification: Medizin, Gesundheit

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2025
• Creator: Tremamunno, Giuseppe ; Pinos, Daniel ; Zsarnóczay, Emese ; Schoepf, U. J. ; Vecsey-Nagy, Milan ; Gnasso, Chiara ; Fink, Nicola ; Kravchenko, Dmitrij ; Hagar, Muhammad Taha ; Griffith, Joseph ; O’Doherty, Jim ; Laghi, Andrea ; Emrich, Tilman ; Varga-Szemes, Akos

Further information

• DOI: 10.1186/s13244-025-01927-5
• URN: urn:nbn:de:bsz:25-freidok-2635073
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:29 AM CEST