Generating synthetic contrast enhancement from non-contrast chest computed tomography using a generative adversarial network

• Published in: Scientific reports Vol. 11; no. 1; p. 20403
• Main Authors: Choi, Jae Won, Cho, Yeon Jin, Ha, Ji Young, Lee, Seul Bi, Lee, Seunghyun, Choi, Young Hun, Cheon, Jung-Eun, Kim, Woo Sun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.10.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 692/700/1421; 692/700/1421/1846; Aged; Chest; Computed tomography; Deep Learning; Female; Humanities and Social Sciences; Humans; Image Processing, Computer-Assisted - methods; Lesions; Lymph nodes; Lymph Nodes - diagnostic imaging; Lymphatic system; Male; Mediastinum; Middle Aged; multidisciplinary; Noise; Radiography, Thoracic - methods; Retrospective Studies; Science; Science (multidisciplinary); Signal-To-Noise Ratio; Supervised Machine Learning; Tomography, X-Ray Computed - methods
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-00058-3

This study aimed to evaluate a deep learning model for generating synthetic contrast-enhanced CT (sCECT) from non-contrast chest CT (NCCT). A deep learning model was applied to generate sCECT from NCCT. We collected three separate data sets, the development set (n = 25) for model training and tuning, test set 1 (n = 25) for technical evaluation, and test set 2 (n = 12) for clinical utility evaluation. In test set 1, image similarity metrics were calculated. In test set 2, the lesion contrast-to-noise ratio of the mediastinal lymph nodes was measured, and an observer study was conducted to compare lesion conspicuity. Comparisons were performed using the paired t-test or Wilcoxon signed-rank test. In test set 1, sCECT showed a lower mean absolute error (41.72 vs 48.74; P  < .001), higher peak signal-to-noise ratio (17.44 vs 15.97; P  < .001), higher multiscale structural similarity index measurement (0.84 vs 0.81; P  < .001), and lower learned perceptual image patch similarity metric (0.14 vs 0.15; P  < .001) than NCCT. In test set 2, the contrast-to-noise ratio of the mediastinal lymph nodes was higher in the sCECT group than in the NCCT group (6.15 ± 5.18 vs 0.74 ± 0.69; P  < .001). The observer study showed for all reviewers higher lesion conspicuity in NCCT with sCECT than in NCCT alone ( P  ≤ .001). Synthetic CECT generated from NCCT improves the depiction of mediastinal lymph nodes.