Motion compensated reconstruction improves image quality and interpretability of dual-layer coronary CT angiography

OBJECTIVES: Reducing motion artifacts in coronary computed tomography angiography (CCTA) is essential for accurate coronary artery disease assessment. We evaluated the clinical performance of a motion-compensated reconstruction (MCR) using subjective image quality (SIQ) and interpretability of CCTA at varying heart rates (HR).

MATERIALS AND METHODS: We retrospectively identified 150 patients, grouped by HR (≤ 60, 60-69, ≥ 70 bpm, n = 50 each), referred for prospective ECG-gated CCTA on a spectral dual-layer CT. Two blinded observers independently assessed SIQ on a per-segment (≥ 1.5 mm) and per-patient level using a 4-point Likert scale in 18 coronary segments (78% RR-interval). Sufficient diagnostic interpretability was defined as SIQ ≥ 2. Per-vessel scores were calculated excluding side branch segments. Per-segment SIQ interobserver agreement was assessed using Cohen's Weighted Kappa. Between MCR and standard reconstruction (SR) at 78% RR-interval, SIQ was compared with Wilcoxon signed-rank tests and diagnostic interpretability and HR-categories using McNemar tests.

RESULTS: Mean age was 57 (50-64) years, with 50% men, and 1970 included segments. Interobserver agreement was 0.80 for SR and 0.77 for MCR. Positive trends of improved SIQ were seen across all HR-categories and levels, with significant improvements in all but ≥ 70 bpm on a patient level (p = 0.22). Likewise, positive trends were seen for diagnostic interpretability across all levels and HR-categories with significant improvements at the per-segment level for HR > 60 bpm and per-patient level for 61-69 bpm.

CONCLUSION: Compared to the standard reconstruction at 78% RR-interval, MCR significantly improves SIQ and diagnostic interpretability in patients referred for CCTA in most HRs and major vessels (≥ 1.5 mm).

KEY POINTS: Question Motion artifacts hinder the assessment of coronary arteries on coronary CT angiography (CCTA), leading to more non-diagnostic segments or scans. Findings Compared to the standard reconstruction 78% RR-interval, motion compensated reconstruction (MCR) significantly improves subjective image quality (SIQ) and diagnostic interpretability across heart rate categories. Clinical relevance By integrating multi-phase data into an optimized single-phase reconstruction with improved SIQ and diagnostic interpretability, MCR may reduce the need for multi-phase assessments when the target phase is non-diagnostic.