{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T07:22:48Z","timestamp":1765610568527,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,5,29]],"date-time":"2025-05-29T00:00:00Z","timestamp":1748476800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"NSFC","doi-asserted-by":"publisher","award":["62276105","3502Z20227193","2023J01136"],"award-info":[{"award-number":["62276105","3502Z20227193","2023J01136"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Xiamen, China","award":["62276105","3502Z20227193","2023J01136"],"award-info":[{"award-number":["62276105","3502Z20227193","2023J01136"]}]},{"DOI":"10.13039\/501100003392","name":"Natural Science Foundation of Fujian Province","doi-asserted-by":"publisher","award":["62276105","3502Z20227193","2023J01136"],"award-info":[{"award-number":["62276105","3502Z20227193","2023J01136"]}],"id":[{"id":"10.13039\/501100003392","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Abdominal organ segmentation in CT images is crucial for accurate diagnosis, treatment planning, and condition monitoring. However, the annotation process is often hindered by challenges such as low contrast, artifacts, and complex organ structures. While unsupervised domain adaptation (UDA) has shown promise in addressing these issues by transferring knowledge from a different modality (source domain), its reliance on both source and target data during training presents a practical challenge in many clinical settings due to data privacy concerns. This study aims to develop a cross-modality abdominal multi-organ segmentation model for label-free CT (target domain) data, leveraging knowledge solely from a pre-trained source domain (MRI) model without accessing the source data. To achieve this, we generate source-like images from target-domain images using a one-way image translation approach with the pre-trained model. These synthesized images preserve the anatomical structure of the target, enabling segmentation predictions from the pre-trained model. To further enhance segmentation accuracy, particularly for organ boundaries and small contours, we introduce an auxiliary translation module with an image decoder and multi-level discriminator. The results demonstrate significant improvements across several performance metrics, including the Dice similarity coefficient (DSC) and average symmetric surface distance (ASSD), highlighting the effectiveness of the proposed method.<\/jats:p>","DOI":"10.3390\/info16060460","type":"journal-article","created":{"date-parts":[[2025,5,29]],"date-time":"2025-05-29T09:47:34Z","timestamp":1748512054000},"page":"460","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Source-Free Domain Adaptation for Cross-Modality Abdominal Multi-Organ Segmentation Challenges"],"prefix":"10.3390","volume":"16","author":[{"given":"Xiyu","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Computer Science and Technology, Huaqiao University, Xiamen 361021, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0367-3003","authenticated-orcid":false,"given":"Xu","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Huaqiao University, Xiamen 361021, China"},{"name":"Key Laboratory of Computer Vision and Machine Learning (Huaqiao University), Fujian Province University, Xiamen 361021, China"},{"name":"Xiamen Key Laboratory of Computer Vision and Pattern Recognition, Huaqiao University, Xiamen 361021, China"}]},{"given":"Yang","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Huaqiao University, Xiamen 361021, China"}]},{"given":"Dongliang","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Huaqiao University, Xiamen 361021, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4790-6086","authenticated-orcid":false,"given":"Yifeng","family":"Hong","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Huaqiao University, Xiamen 361021, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1243","DOI":"10.1049\/ipr2.12419","article-title":"Medical image segmentation using deep learning: A survey","volume":"16","author":"Wang","year":"2022","journal-title":"IET Image Process."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1007\/s10278-019-00262-8","article-title":"Survey on liver tumour resection planning system: Steps, techniques, and parameters","volume":"33","author":"Alirr","year":"2020","journal-title":"J. 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