{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T10:00:25Z","timestamp":1777975225650,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2020,7,16]],"date-time":"2020-07-16T00:00:00Z","timestamp":1594857600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010663","name":"H2020 European Research Council","doi-asserted-by":"publisher","award":["637780"],"award-info":[{"award-number":["637780"]}],"id":[{"id":"10.13039\/100010663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["713690"],"award-info":[{"award-number":["713690"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The dielectric characterization of tissue targets of microwave thermal ablation (MTA) have improved the efficacy and pre-procedural planning of treatment. In some clinical scenarios, the tissue target lies at the interface with an external layer of fat. The aim of this work is to investigate the influence of the dielectric contrast between fat and target tissue on the shape and size of the ablation zone. A 2.45 GHz monopole antenna is placed parallel to an interface modelled by fat and a tissue characterized by higher dielectric properties and powered at 30 and 60 W for 60 s. The performances of MTA are numerically investigated considering different interface scenarios (i.e., different widths of fat layer, shifts in the antenna alignment) and a homogeneous reference scenario. Experiments (N = 10) are conducted on ex vivo porcine tissue to validate the numerical results. Asymmetric heating patterns are obtained in the interface scenario, the ablation zone in the target tissue is two-fold to ten-fold the size of the zone in the adipose tissue, and up to four times larger than the homogenous scenario. The adipose tissue reflects the electromagnetic energy into the adjacent tissue target, reducing the heating in the opposite direction.<\/jats:p>","DOI":"10.3390\/s20143960","type":"journal-article","created":{"date-parts":[[2020,7,16]],"date-time":"2020-07-16T10:54:46Z","timestamp":1594896886000},"page":"3960","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Exploiting Tissue Dielectric Properties to Shape Microwave Thermal Ablation Zones"],"prefix":"10.3390","volume":"20","author":[{"given":"Anna","family":"Bottiglieri","sequence":"first","affiliation":[{"name":"Electrical and Electronic Engineering, National University of Ireland Galway, H91 TK33 Galway, Ireland"},{"name":"Translational Medical Device Lab, National University of Ireland Galway, H91 TK33 Galway, Ireland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5642-4035","authenticated-orcid":false,"given":"Giuseppe","family":"Ruvio","sequence":"additional","affiliation":[{"name":"Translational Medical Device Lab, National University of Ireland Galway, H91 TK33 Galway, Ireland"},{"name":"Endowave Ltd., National University of Ireland Galway, H91 TK33 Galway, Ireland"}]},{"given":"Martin","family":"O\u2019Halloran","sequence":"additional","affiliation":[{"name":"Translational Medical Device Lab, National University of Ireland Galway, H91 TK33 Galway, Ireland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1571-8037","authenticated-orcid":false,"given":"Laura","family":"Farina","sequence":"additional","affiliation":[{"name":"Translational Medical Device Lab, National University of Ireland Galway, H91 TK33 Galway, Ireland"},{"name":"C\u00daRAM, SFI Research Centre for Medical Devices, H91 TK33 Galway, Ireland"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1148\/radiol.10081634","article-title":"Principles of and advances in percutaneous ablation","volume":"258","author":"Ahmed","year":"2011","journal-title":"Radiology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1109\/MPUL.2011.942603","article-title":"Thermal tumour ablation in clinical use","volume":"2","author":"Brace","year":"2011","journal-title":"IEEE Pulse"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Liang, P., Yu, X.L., and Yu, J. 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