Background To assess whether radiomics analysis of carotid ultrasound (CUS) can identify texture features associated with severe coronary artery calcification, even in individuals without carotid plaque.

Methods This study included 105 participants with coronary artery calcium score (CACS) > 400 and no carotid plaque, matched by age and sex to 105 controls with CACS=0. B-mode CUS images of the bilateral distal common carotid arteries (CCA) were analyzed, with 1-cm longitudinal regions of interest extending from the lumen to the adventitia. Radiomic features were extracted from each frame, filtered by variance and correlation, and ranked using bootstrap-based XGBoost feature importance (FI) and evaluated on internal and external datasets.

Results Among 700 extracted features, the final retained features were reproducible: 8 (right) and 11 (left) for CACS=0, and 7 (right) and 10 (left) for CACS > 400 (all p < 0.05). Group-specific features, observed only in the CACS 0 or CACS > 400 group, included 90th Percentile (CACS=0: right distal CCA, FI=0.030; left distal CCA, FI=0.025) and Run Entropy (CACS > 400: right distal CCA, FI=0.046; left distal CCA, FI=0.038). Shared features such as Long Run Emphasis, Dependence Non-Uniformity, and Entropy were consistently observed across both groups and sides (FI=0.023-0.029), with Dependence Non-Uniformity consistent in the left distal CCA across both groups and datasets.

Conclusions Although no plaque was detected on CUS, radiomics can identify ultrasound texture patterns associated with severe coronary calcification. This approach may improve detection of high-risk individuals who would otherwise be classified as low-risk by CUS alone.

Graphic Abstract Texture-Based Radiomics of Carotid Ultrasound Reveals Severe Coronary Calcification. (A), Imaging modalities and study population: Adults undergoing health screenings at tertiary hospitals in City A and City B (2018–2022) who received same-day carotid ultrasound and CACS CT. After excluding plaque, CVD history, and poor image quality, 105 plaque-free participants with CACS > 400 were identified and age- and sex-matched to 105 plaque-free participants with CACS = 0. (B), Radiomics pipeline: carotid ultrasound images were segmented, preprocessed, filtered, and processed for feature extraction and selection, yielding reproducible texture features. (C), Radiomics feature maps: representative examples of plaque-free carotid ultrasound in patients with CACS = 0 and CACS >400. Entropy and dependence non-uniformity maps demonstrate distinct texture patterns associated with severe coronary calcification.

The authors have declared no competing interest.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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This retrospective study was approved by the institutional review board of Kangbuk Samsung Hospital (approval no. 2024-03-023); informed consent was waived due to the use of pre-existing, de-identified health screening data.

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Footnotes

† These authors jointly supervised this work as co–corresponding authors.