{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,22]],"date-time":"2026-03-22T17:55:26Z","timestamp":1774202126207,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,8,23]],"date-time":"2024-08-23T00:00:00Z","timestamp":1724371200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"International Graduate School MEMoRIAL at Otto von Guericke University (OVGU) Magdeburg, Germany","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"International Graduate School MEMoRIAL at Otto von Guericke University (OVGU) Magdeburg, Germany","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"International Graduate School MEMoRIAL at Otto von Guericke University (OVGU) Magdeburg, Germany","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"International Graduate School MEMoRIAL at Otto von Guericke University (OVGU) Magdeburg, Germany","award":["I 88"],"award-info":[{"award-number":["I 88"]}]},{"name":"European Structural and Investment Funds (ESF)","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"European Structural and Investment Funds (ESF)","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"European Structural and Investment Funds (ESF)","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"European Structural and Investment Funds (ESF)","award":["I 88"],"award-info":[{"award-number":["I 88"]}]},{"name":"Initial Training Network programme, HiMR","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"Initial Training Network programme, HiMR","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"Initial Training Network programme, HiMR","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"Initial Training Network programme, HiMR","award":["I 88"],"award-info":[{"award-number":["I 88"]}]},{"name":"FP7 Marie Curie Actions of the European Commission","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"FP7 Marie Curie Actions of the European Commission","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"FP7 Marie Curie Actions of the European Commission","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"FP7 Marie Curie Actions of the European Commission","award":["I 88"],"award-info":[{"award-number":["I 88"]}]},{"name":"NIH","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"NIH","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"NIH","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"NIH","award":["I 88"],"award-info":[{"award-number":["I 88"]}]},{"name":"State of Saxony-Anhalt","award":["ZS\/08\/80646"],"award-info":[{"award-number":["ZS\/08\/80646"]}]},{"name":"State of Saxony-Anhalt","award":["FP7-PEOPLE-2012-ITN-316716"],"award-info":[{"award-number":["FP7-PEOPLE-2012-ITN-316716"]}]},{"name":"State of Saxony-Anhalt","award":["1R01-DA021146"],"award-info":[{"award-number":["1R01-DA021146"]}]},{"name":"State of Saxony-Anhalt","award":["I 88"],"award-info":[{"award-number":["I 88"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>High-spatial resolution MRI produces abundant structural information, enabling highly accurate clinical diagnosis and image-guided therapeutics. However, the acquisition of high-spatial resolution MRI data typically can come at the expense of less spatial coverage, lower signal-to-noise ratio (SNR), and longer scan time due to physical, physiological and hardware limitations. In order to overcome these limitations, super-resolution MRI deep-learning-based techniques can be utilised. In this work, different state-of-the-art 3D convolution neural network models for super resolution (RRDB, SPSR, UNet, UNet-MSS and ShuffleUNet) were compared for the super-resolution task with the goal of finding the best model in terms of performance and robustness. The public IXI dataset (only structural images) was used. Data were artificially downsampled to obtain lower-resolution spatial MRIs (downsampling factor varying from 8 to 64). When assessing performance using the SSIM metric in the test set, all models performed well. In particular, regardless of the downsampling factor, the UNet consistently obtained the top results. On the other hand, the SPSR model consistently performed worse. In conclusion, UNet and UNet-MSS achieved overall top performances while RRDB performed relatively poorly compared to the other models.<\/jats:p>","DOI":"10.3390\/jimaging10090207","type":"journal-article","created":{"date-parts":[[2024,8,23]],"date-time":"2024-08-23T12:53:19Z","timestamp":1724417599000},"page":"207","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Beyond Nyquist: A Comparative Analysis of 3D Deep Learning Models Enhancing MRI Resolution"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7594-1188","authenticated-orcid":false,"given":"Soumick","family":"Chatterjee","sequence":"first","affiliation":[{"name":"Data and Knowledge Engineering Group, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"Genomics Research Centre, Human Technopole, 20157 Milan, Italy"}]},{"given":"Alessandro","family":"Sciarra","sequence":"additional","affiliation":[{"name":"Department of Biomedical Magnetic Resonance, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"MedDigit, Department of Neurology, Medical Faculty, University Hospital Magdeburg, 39120 Magdeburg, Germany"}]},{"given":"Max","family":"D\u00fcnnwald","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"MedDigit, Department of Neurology, Medical Faculty, University Hospital Magdeburg, 39120 Magdeburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7717-6943","authenticated-orcid":false,"given":"Anitha Bhat Talagini","family":"Ashoka","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"Fraunhofer Institute for Digital Media Technology, 98693 Ilmenau, Germany"}]},{"given":"Mayura Gurjar Cheepinahalli","family":"Vasudeva","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"}]},{"given":"Shudarsan","family":"Saravanan","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6974-7669","authenticated-orcid":false,"given":"Venkatesh Thirugnana","family":"Sambandham","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"}]},{"given":"Pavan","family":"Tummala","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"}]},{"given":"Steffen","family":"Oeltze-Jafra","sequence":"additional","affiliation":[{"name":"MedDigit, Department of Neurology, Medical Faculty, University Hospital Magdeburg, 39120 Magdeburg, Germany"},{"name":"German Centre for Neurodegenerative Diseases, 37075 Magdeburg, Germany"},{"name":"Centre for Behavioural Brain Sciences, 39106 Magdeburg, Germany"},{"name":"Peter L. Reichertz Institute for Medical Informatics, Hannover Medical School, 30625 Hannover, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6019-5597","authenticated-orcid":false,"given":"Oliver","family":"Speck","sequence":"additional","affiliation":[{"name":"Department of Biomedical Magnetic Resonance, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"German Centre for Neurodegenerative Diseases, 37075 Magdeburg, Germany"},{"name":"Centre for Behavioural Brain Sciences, 39106 Magdeburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4311-0624","authenticated-orcid":false,"given":"Andreas","family":"N\u00fcrnberger","sequence":"additional","affiliation":[{"name":"Data and Knowledge Engineering Group, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"Faculty of Computer Science, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany"},{"name":"Centre for Behavioural Brain Sciences, 39106 Magdeburg, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2459","DOI":"10.1109\/TMI.2015.2437894","article-title":"LRTV: MR Image Super-Resolution with Low-Rank and Total Variation Regularizations","volume":"34","author":"Shi","year":"2015","journal-title":"IEEE Trans. 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Sens."}],"container-title":["Journal of Imaging"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2313-433X\/10\/9\/207\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:42:18Z","timestamp":1760110938000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2313-433X\/10\/9\/207"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,8,23]]},"references-count":31,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2024,9]]}},"alternative-id":["jimaging10090207"],"URL":"https:\/\/doi.org\/10.3390\/jimaging10090207","relation":{},"ISSN":["2313-433X"],"issn-type":[{"value":"2313-433X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,8,23]]}}}