{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T00:04:27Z","timestamp":1773446667899,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,11]],"date-time":"2025-05-11T00:00:00Z","timestamp":1746921600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2023YFE0205600"],"award-info":[{"award-number":["2023YFE0205600"]}]},{"name":"the National Key Research and Development Program of China","award":["62272415"],"award-info":[{"award-number":["62272415"]}]},{"name":"the National Key Research and Development Program of China","award":["2023C01041"],"award-info":[{"award-number":["2023C01041"]}]},{"name":"the National Key Research and Development Program of China","award":["2024C03070"],"award-info":[{"award-number":["2024C03070"]}]},{"name":"the National Key Research and Development Program of China","award":["2023BEG02065"],"award-info":[{"award-number":["2023BEG02065"]}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023YFE0205600"],"award-info":[{"award-number":["2023YFE0205600"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62272415"],"award-info":[{"award-number":["62272415"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023C01041"],"award-info":[{"award-number":["2023C01041"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2024C03070"],"award-info":[{"award-number":["2024C03070"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023BEG02065"],"award-info":[{"award-number":["2023BEG02065"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Key Research and Development Program of Zhejiang Province","award":["2023YFE0205600"],"award-info":[{"award-number":["2023YFE0205600"]}]},{"name":"the Key Research and Development Program of Zhejiang Province","award":["62272415"],"award-info":[{"award-number":["62272415"]}]},{"name":"the Key Research and Development Program of Zhejiang Province","award":["2023C01041"],"award-info":[{"award-number":["2023C01041"]}]},{"name":"the Key Research and Development Program of Zhejiang Province","award":["2024C03070"],"award-info":[{"award-number":["2024C03070"]}]},{"name":"the Key Research and Development Program of Zhejiang Province","award":["2023BEG02065"],"award-info":[{"award-number":["2023BEG02065"]}]},{"name":"the Key Research and Development Program of Ningxia Province","award":["2023YFE0205600"],"award-info":[{"award-number":["2023YFE0205600"]}]},{"name":"the Key Research and Development Program of Ningxia Province","award":["62272415"],"award-info":[{"award-number":["62272415"]}]},{"name":"the Key Research and Development Program of Ningxia Province","award":["2023C01041"],"award-info":[{"award-number":["2023C01041"]}]},{"name":"the Key Research and Development Program of Ningxia Province","award":["2024C03070"],"award-info":[{"award-number":["2024C03070"]}]},{"name":"the Key Research and Development Program of Ningxia Province","award":["2023BEG02065"],"award-info":[{"award-number":["2023BEG02065"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Magnetic Resonance Imaging (MRI) is a widely used, non-invasive imaging technology that plays a critical role in clinical diagnostics. Multi-modal MRI, which combines images from different modalities, enhances diagnostic accuracy by offering comprehensive tissue characterization. Meanwhile, multi-modal MRI enhances downstream tasks, like brain tumor segmentation and image reconstruction, by providing richer features. While recent advances in diffusion models (DMs) show potential for high-quality image translation, existing methods still struggle to preserve fine structural details and ensure accurate image synthesis in medical imaging. To address these challenges, we propose a Frequency-Aware Diffusion Model (FADM) for generating high-quality target modality MRI images from source modality images. The FADM incorporates a discrete wavelet transform within the diffusion model framework to extract both low- and high-frequency information from MRI images, enhancing the capture of tissue structural and textural features. Additionally, a wavelet downsampling layer and supervision module are incorporated to improve frequency awareness and optimize high-frequency detail extraction. Experimental results on the BraTS 2021 dataset and a 1.5T\u20133T MRI dataset demonstrate that the FADM outperforms existing generative models, particularly in preserving intricate brain structures and tumor regions while generating high-quality MRI images.<\/jats:p>","DOI":"10.3390\/jimaging11050152","type":"journal-article","created":{"date-parts":[[2025,5,12]],"date-time":"2025-05-12T04:21:23Z","timestamp":1747023683000},"page":"152","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Frequency-Aware Diffusion Model for Multi-Modal MRI Image Synthesis"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3013-4790","authenticated-orcid":false,"given":"Mingfeng","family":"Jiang","sequence":"first","affiliation":[{"name":"School of Computer Science and Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China"}]},{"given":"Peihang","family":"Jia","sequence":"additional","affiliation":[{"name":"School of Computer Science and Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7113-5066","authenticated-orcid":false,"given":"Xin","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Computer Science and Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China"}]},{"given":"Zihan","family":"Yuan","sequence":"additional","affiliation":[{"name":"School of Computer Science and Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China"}]},{"given":"Dongsheng","family":"Ruan","sequence":"additional","affiliation":[{"name":"School of Computer Science and Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China"}]},{"given":"Feng","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia"}]},{"given":"Ling","family":"Xia","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,11]]},"reference":[{"key":"ref_1","unstructured":"Iglesias, J.E., Konukoglu, E., Zikic, D., Glocker, B., Van Leemput, K., and Fischl, B. 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