Optimizing coronary CT angiography quality with motion-compensated reconstruction for second-generation dual-layer spectral detector CT.

Objectives: To investigate the effect of motion-compensated reconstruction (MCR) algorithm on improving the image quality of coronary computed tomography angiography (CCTA) using second-generation dual-layer spectral detector computed tomography (DLCT), and to evaluate the influence of heart rate (HR) on the motion-correction efficacy of this algorithm.

Materials and methods: We retrospectively enrolled 127 patients who underwent CCTA for suspected coronary artery disease using second-generation DLCT. We divided the patients into two subgroups according to their average HR during scanning: the "HR < 75 bpm" group and the "HR ≥ 75 bpm" group. All images were reconstructed by the standard (STD) algorithm and MCR algorithm. Subjective image quality (4-point Likert scale), interpretability, and objective image quality between the STD and MCR in the whole population and within each subgroup were compared.

Results: MCR showed significantly higher Likert scores and interpretability than STD on the per-segment (3.58 ± 0.69 vs. 2.82 ± 0.93, 98.4% vs. 91.9%), per-vessel (3.12 ± 0.81 vs. 2.12 ± 0.74, 96.3% vs. 78.7%) and per-patient (2.57 ± 0.76 vs. 1.62 ± 0.55, 90.6% vs. 59.1%) levels (all p < 0.001). In the analysis of HR subgroups on a per-vessel basis of interpretability, significant differences were observed only in the right coronary artery in the low HR group, whereas significant differences were noted in three major coronary arteries in the high HR group. For objective image quality assessment, MCR significantly improved the SNR (13.22 ± 4.06 vs. 12.72 ± 4.06) and the contrast-to-noise ratio (15.84 ± 4.82 vs. 15.39 ± 4.38) compared to STD (both p < 0.001).

Conclusion: MCR significantly improves the subjective image quality, interpretability, and objective image quality of CCTA, especially in patients with higher HRs.

Clinical relevance statement: The motion-compensated reconstruction algorithm of the second-generation dual-layer spectral detector computed tomography is helpful in improving the image quality of coronary computed tomography angiography in clinical practice, especially in patients with higher heart rates.

Key points: Motion artifacts from cardiac movement affect the quality and interpretability of coronary computed tomography angiography (CCTA). This motion-compensated reconstruction (MCR) algorithm significantly improves the image quality of CCTA in clinical practice. Image quality improvement by using MCR was more significant in the high heart rate group.