{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T12:21:01Z","timestamp":1767183661828,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,20]],"date-time":"2022-12-20T00:00:00Z","timestamp":1671494400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PON Research and Innovation \u201dMicrowave Imaging and Detection powered by Artificial Intelligence for Medical and Industrial Applications","award":["DM 1062\/21","764479"],"award-info":[{"award-number":["DM 1062\/21","764479"]}]},{"name":"Italian Ministry of University and Research","award":["DM 1062\/21","764479"],"award-info":[{"award-number":["DM 1062\/21","764479"]}]},{"name":"European Union\u2019s Horizon 2020","award":["DM 1062\/21","764479"],"award-info":[{"award-number":["DM 1062\/21","764479"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, the contrast source inversion method is combined with a finite element method to solve microwave imaging problems. The paper\u2019s major contribution is the development of a novel contrast source variable discretization that leads to simplify the algorithm implementation and, at the same time, to improve the accuracy of the discretized quantities. Moreover, the imaging problem is recreated in a synthetic environment, where the antennas, and their corresponding coaxial port, are modeled. The implemented algorithm is applied to reconstruct the tissues\u2019 dielectric properties inside the head for brain stroke microwave imaging. The proposed implementation is compared with the standard one to evaluate the impact of the variables\u2019 discretization on the algorithm\u2019s accuracy. Furthermore, the paper shows the obtained performances with the proposed and the standard implementations of the contrast source inversion method in the same realistic 3D scenario. The exploited numerical example shows that the proposed discretization can reach a better focus on the stroke region in comparison with the standard one. However, the variation is within a limited range of permittivity values, which is reflected in similar averages.<\/jats:p>","DOI":"10.3390\/s23010011","type":"journal-article","created":{"date-parts":[[2022,12,20]],"date-time":"2022-12-20T04:21:56Z","timestamp":1671510116000},"page":"11","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Novel Discretization Procedure in the CSI-FEM Algorithm for Brain Stroke Microwave Imaging"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1359-4912","authenticated-orcid":false,"given":"Valeria","family":"Mariano","sequence":"first","affiliation":[{"name":"Department of Electronics and Telecommunications, Politecnico di Torino, 10129 Torino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4726-5017","authenticated-orcid":false,"given":"Jorge A.","family":"Tobon Vasquez","sequence":"additional","affiliation":[{"name":"Department of Electronics and Telecommunications, Politecnico di Torino, 10129 Torino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0791-9269","authenticated-orcid":false,"given":"Francesca","family":"Vipiana","sequence":"additional","affiliation":[{"name":"Department of Electronics and Telecommunications, Politecnico di Torino, 10129 Torino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"739","DOI":"10.1515\/jiip-2020-0102","article-title":"Microwave thermometry with potential application in non-invasive monitoring of hyperthermia","volume":"28","author":"Aram","year":"2020","journal-title":"J. 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