{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T17:36:44Z","timestamp":1767893804546,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,3]],"date-time":"2021-12-03T00:00:00Z","timestamp":1638489600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Social Fund - ESF","award":["MIS-5050329"],"award-info":[{"award-number":["MIS-5050329"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>In the current work, a pix2pix conditional generative adversarial network has been evaluated as a potential solution for generating adequately accurate synthesized morphological X-ray images by translating standard photographic images of mice. Such an approach will benefit 2D functional molecular imaging techniques, such as planar radioisotope and\/or fluorescence\/bioluminescence imaging, by providing high-resolution information for anatomical mapping, but not for diagnosis, using conventional photographic sensors. Planar functional imaging offers an efficient alternative to biodistribution ex vivo studies and\/or 3D high-end molecular imaging systems since it can be effectively used to track new tracers and study the accumulation from zero point in time post-injection. The superimposition of functional information with an artificially produced X-ray image may enhance overall image information in such systems without added complexity and cost. The network has been trained in 700 input (photography)\/ground truth (X-ray) paired mouse images and evaluated using a test dataset composed of 80 photographic images and 80 ground truth X-ray images. Performance metrics such as peak signal-to-noise ratio (PSNR), structural similarity index measure (SSIM) and Fr\u00e9chet inception distance (FID) were used to quantitatively evaluate the proposed approach in the acquired dataset.<\/jats:p>","DOI":"10.3390\/jimaging7120262","type":"journal-article","created":{"date-parts":[[2021,12,5]],"date-time":"2021-12-05T21:01:45Z","timestamp":1638738105000},"page":"262","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Optical to Planar X-ray Mouse Image Mapping in Preclinical Nuclear Medicine Using Conditional Adversarial Networks"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5616-4563","authenticated-orcid":false,"given":"Eleftherios","family":"Fysikopoulos","sequence":"first","affiliation":[{"name":"Biomedical Engineering Department, University of West Attica, 12210 Athens, Greece"},{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"given":"Maritina","family":"Rouchota","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Department, University of West Attica, 12210 Athens, Greece"},{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2103-1047","authenticated-orcid":false,"given":"Vasilis","family":"Eleftheriadis","sequence":"additional","affiliation":[{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"given":"Christina-Anna","family":"Gatsiou","sequence":"additional","affiliation":[{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4760-2845","authenticated-orcid":false,"given":"Irinaios","family":"Pilatis","sequence":"additional","affiliation":[{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4323-3165","authenticated-orcid":false,"given":"Sophia","family":"Sarpaki","sequence":"additional","affiliation":[{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"given":"George","family":"Loudos","sequence":"additional","affiliation":[{"name":"BIOEMTECH, Lefkippos Attica Technology Park, N.C.S.R. Democritos, 15343 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0223-2502","authenticated-orcid":false,"given":"Spiros","family":"Kostopoulos","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Department, University of West Attica, 12210 Athens, Greece"}]},{"given":"Dimitrios","family":"Glotsos","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Department, University of West Attica, 12210 Athens, Greece"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1038\/nrd2290","article-title":"Molecular imaging in drug development","volume":"7","author":"Willmann","year":"2008","journal-title":"Nat. Rev. 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