Figure 2.

Axial cardiac CT images of a 75-year-old man (body mass index, 26.5 kg/m²) reconstructed using FBP, ASIR-V 50%, and three levels of DLIR (DLIR-L, M, and H, respectively), The section thickness was 2.5 mm. Image noise was 31.1, 23, 26.2, 20.9, and 18.1 HU in the left ventricle from (A) to (E). At the level of the distal segment of the RCA, calcified lesions were marked manually in red dots. Scattered false-positive dots were marked in green automatically on FBP (A), ASIR-V 50% (B), and DLIR (with incremental strength levels) (C-E) images. One calcified plaque could not be detected in the ASIR-V 50% group (white arrows). FBP, filtered back projection; ASIR-V, adaptive statistical iterative reconstruction-V; RCA, right coronary artery; DLIR-L, DLIR-M, and DLIR-H: deep learning image reconstruction at low, medium, and high levels, respectively.