Dual-energy based myocardial extracellular volume quantification with photon-counting detector and energy-integrating
Shouyu Bao1, Mi Zhou2, Mengzhen Wang1
1Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Objectives:
This study compared three-dimensional myocardial extracellular volume (ECV) quantification among single-phase and dual-phase photon-counting detector computed tomography (PCD-CT) and dual-phase energy-integrating detector computed tomography (EID-CT), using cardiac magnetic resonance (CMR) imaging as the reference.
Materials And Methods:
This retrospective study included 80 patients who underwent both CMR and cardiac CT (40 patients underwent PCD-CT and 40 underwent EID-CT). Pearson correlation coefficients and intraclass correlation coefficients (ICCs) were used to evaluate the correlation and reliability of CT-ECV with CMR-ECV. Subgroup analysis was performed based on heart rate.
Results:
The single-phase and dual-phase ECV measurements on PCD-CT showed excellent correlation and consistency with CMR (correlation coefficient: single-phase, 0.84; dual-phase, 0.91; ICC: single-phase, 0.90; dual-phase, 0.94). Both methods significantly outperformed EID-CT (correlation coefficient: 0.62; ICC: 0.76; all p < 0.05). No significant differences were observed between the two PCD-CT methods (all p > 0.05). PCD-CT demonstrated high consistency across both HR subgroups (ICC: HR ≤ 60 bpm: 0.89 for single-phase, 0.85 for dual-phase; HR > 60 bpm: 0.87 for single-phase, 0.88 for dual-phase), whereas EID-CT exhibited reduced consistency in patients with HR > 60 bpm (ICC: HR ≤ 60 bpm: 0.78; HR > 60 bpm: 0.60).
Conclusion:
Compared with EID-CT, PCD-CT showed superior correlation and reliability for myocardial ECV quantification, particularly in patients with elevated heart rates. The single-phase PCD-CT method demonstrated performance equivalent to the dual-phase approach.
Key Points:
Question How does myocardial ECV quantification using PCD-CT compare with conventional EID-CT? Findings Single-phase and dual-phase methods on PCD-CT significantly outperform EID-CT in myocardial ECV quantification. Clinical relevance These findings suggest PCD-CT significantly outperforms EID-CT as a promising alternative to CMR for myocardial ECV assessment, particularly under challenging conditions such as higher heart rates, offering improved reliability for clinical myocardial tissue characterization.
