{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T02:32:05Z","timestamp":1783650725748,"version":"3.55.0"},"reference-count":43,"publisher":"Wiley","issue":"12","license":[{"start":{"date-parts":[[2025,12,10]],"date-time":"2025-12-10T00:00:00Z","timestamp":1765324800000},"content-version":"vor","delay-in-days":9,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100012818","name":"Comunidad de Madrid","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100012818","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["aapm.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["J Applied Clin Med Phys"],"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Proton therapy (PT) is recognized as a superior treatment for head cancer (HC) due to its precision and minimal damage to surrounding healthy tissues, relying on computed tomography (CT) data for dose calculations. Adaptive proton therapy (APT) is crucial to address changes in patient anatomy during treatment and update dose accuracy. However, in\u2010room cone\u2010beam CT (CBCT) assistance is limited to assessing patient setup, with occasional constraints due to artifacts and\/or lower image quality and resolution compared to a CT scan.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Although deep learning (DL) techniques can successfully convert a CBCT into a synthetic CT (sCT), soft tissue delineation remains a challenging task. We hypothesized that, by including Magnetic Resonance Image (MRI) in CBCT\u2010based CT synthesis, the sCT generation could more closely approximate the CT ground truth while improving tissue definition and dose calculation in PT treatment planning.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We propose a Pix2Pix\u2010conditional generative adversarial network (cGAN) to synthesize a CT scan by combining two different input images: CBCT and T1\u2010weighted MRI. ResUnet and SwinUnet were evaluated as the cGAN generator. Additionally, a CBCT\u2010only\u2010based CycleGAN was tested.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Model performance improved with the inclusion of MRI data, especially in recovering soft tissue details like eyes and ventricles, with ResUnet models outperforming SwinUnet models. Our cGAN outperformed both the self\u2010autoencoder approaches and the CycleGAN model. Pix2Pix\u2010ResUnet (MR\u2010based) significantly reduced average HU errors in volumes of interest and also enhanced the precision in dose values, as demonstrated in dose differences and profiles.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>We demonstrated the promising contribution of MRI to CBCT\u2010based CT synthesis, enhancing sCT image quality and dose calculation accuracy. Future efforts should aim to collect a larger dataset and validate the integration of MRI in\u00a0APT.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/acm2.70367","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T04:58:33Z","timestamp":1765429113000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Enhancing CBCT\u2010based CT synthesis using planning MRI in adaptive proton therapy for head cancer: A deep learning approach"],"prefix":"10.1002","volume":"26","author":[{"given":"Juan Manuel","family":"Molina\u2010Maza","sequence":"first","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Viar\u2010Hernandez","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Blanca","family":"Rodriguez\u2010Gonzalez","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Sequeiro\u2010Gonzalez","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Antonio","family":"Vera\u2010Sanchez","sequence":"additional","affiliation":[{"name":"Centro de Protonterapia Quironsalud Servicio de F\u00edsica M\u00e9dica Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro","family":"Mazal","sequence":"additional","affiliation":[{"name":"Centro de Protonterapia Quironsalud Servicio de F\u00edsica M\u00e9dica Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Norberto","family":"Malpica","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1540-2809","authenticated-orcid":false,"given":"Angel","family":"Torrado\u2010Carvajal","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Maria","family":"Perez\u2010Moreno","sequence":"additional","affiliation":[{"name":"Centro de Protonterapia Quironsalud Servicio de F\u00edsica M\u00e9dica Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Borja","family":"Rodriguez\u2010Vila","sequence":"additional","affiliation":[{"name":"Universidad Rey Juan Carlos Medical Image Analysis and Biometry Laboratory Madrid Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,12,10]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.addr.2016.11.006"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/ab7d54"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13390"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.3109\/0284186X.2015.1061206"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1186\/s13014-016-0641-7"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/ac344f"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1259\/bjr.20190594"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.17057"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13978"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/ab6240"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.phro.2023.100512"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/ab22f9"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.radonc.2023.110052"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.16777"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejmp.2020.11.007"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.phro.2020.04.002"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13656"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13963"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14121"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14624"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1177\/15330338221085358"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1088\/2057-1976\/acea27"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14418"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14075"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/aada6d"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1109\/ACCESS.2019.2951924"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14062"},{"key":"e_1_2_11_29_1","doi-asserted-by":"publisher","DOI":"10.1093\/jrr\/rrz063"},{"key":"e_1_2_11_30_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.radonc.2020.09.029"},{"key":"e_1_2_11_31_1","doi-asserted-by":"publisher","DOI":"10.1109\/TMI.2020.3015379"},{"key":"e_1_2_11_32_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14866"},{"key":"e_1_2_11_33_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.compmedimag.2021.101953"},{"key":"e_1_2_11_34_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.3190392"},{"key":"e_1_2_11_35_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.mri.2012.05.001"},{"key":"e_1_2_11_36_1","doi-asserted-by":"crossref","unstructured":"IsolaP ZhuJ\u2010Y ZhouT EfrosAA.Image\u2010to\u2010image translation with conditional adversarial networks. In:Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition.IEEE;2017:1125\u20131134.","DOI":"10.1109\/CVPR.2017.632"},{"key":"e_1_2_11_37_1","doi-asserted-by":"crossref","unstructured":"ZhuJ\u2010Y ParkT IsolaP EfrosAA.Unpaired image\u2010to\u2010image translation using cycle\u2010consistent adversarial networks. In:Proceedings of the IEEE International Conference on Computer Vision.IEEE;2017:2223\u20132232.","DOI":"10.1109\/ICCV.2017.244"},{"key":"e_1_2_11_38_1","doi-asserted-by":"crossref","unstructured":"LiuZ LinY CaoY et\u00a0al.Swin transformer: Hierarchical vision transformer using shifted windows. In:Proceedings of the IEEE\/CVF International Conference on Computer Vision.IEEE;2021:10012\u201310022.","DOI":"10.1109\/ICCV48922.2021.00986"},{"key":"e_1_2_11_39_1","doi-asserted-by":"publisher","DOI":"10.1148\/ryai.230024"},{"key":"e_1_2_11_40_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41592-020-01008-z"},{"key":"e_1_2_11_41_1","doi-asserted-by":"publisher","DOI":"10.1186\/s13104-022-06096-y"},{"key":"e_1_2_11_42_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12880-015-0068-x"},{"key":"e_1_2_11_43_1","doi-asserted-by":"crossref","unstructured":"RonnebergerO FischerP BroxT.U\u2010net: convolutional networks for biomedical image segmentation. In:Medical Image Computing and Computer\u2010Assisted Intervention\u2013MICCAI 2015: 18th International Conference Munich Germany October 5\u20109 2015 Proceedings Part III 18.Springer;2015:234\u2013241.","DOI":"10.1007\/978-3-319-24574-4_28"},{"key":"e_1_2_11_44_1","doi-asserted-by":"publisher","DOI":"10.3390\/s19102361"}],"container-title":["Journal of Applied Clinical Medical Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/acm2.70367","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T11:12:58Z","timestamp":1767179578000},"score":1,"resource":{"primary":{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/10.1002\/acm2.70367"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12]]},"references-count":43,"journal-issue":{"issue":"12","published-print":{"date-parts":[[2025,12]]}},"alternative-id":["10.1002\/acm2.70367"],"URL":"https:\/\/doi.org\/10.1002\/acm2.70367","archive":["Portico"],"relation":{},"ISSN":["1526-9914","1526-9914"],"issn-type":[{"value":"1526-9914","type":"print"},{"value":"1526-9914","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12]]},"assertion":[{"value":"2025-04-24","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-10-17","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-12-10","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70367"}}