{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T17:26:40Z","timestamp":1773422800245,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,29]],"date-time":"2024-02-29T00:00:00Z","timestamp":1709164800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Kreutzkamp family to UCSD"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Repetitive transcranial magnetic stimulation (rTMS) is a rapidly developing therapeutic modality for the safe and effective treatment of neuropsychiatric disorders. However, clinical rTMS driving systems and head coils are large, heavy, and expensive, so miniaturized, affordable rTMS devices may facilitate treatment access for patients at home, in underserved areas, in field and mobile hospitals, on ships and submarines, and in space. The central component of a portable rTMS system is a miniaturized, lightweight coil. Such a coil, when mated to lightweight driving circuits, must be able to induce B and E fields of sufficient intensity for medical use. This paper newly identifies and validates salient theoretical considerations specific to the dimensional scaling and miniaturization of coil geometries, particularly figure-8 coils, and delineates novel, key design criteria. In this context, the essential requirement of matching coil inductance with the characteristic resistance of the driver switches is highlighted. Computer simulations predicted E- and B-fields which were validated via benchtop experiments. Using a miniaturized coil with dimensions of 76 mm \u00d7 38 mm and weighing only 12.6 g, the peak E-field was 87 V\/m at a distance of 1.5 cm. Practical considerations limited the maximum voltage and current to 350 V and 3.1 kA, respectively; nonetheless, this peak E-field value was well within the intensity range, 60\u2013120 V\/m, generally held to be therapeutically relevant. The presented parameters and results delineate coil and circuit guidelines for a future miniaturized, power-scalable rTMS system able to generate pulsed E-fields of sufficient amplitude for potential clinical use.<\/jats:p>","DOI":"10.3390\/s24051584","type":"journal-article","created":{"date-parts":[[2024,2,29]],"date-time":"2024-02-29T08:13:44Z","timestamp":1709194424000},"page":"1584","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Design and Validation of Miniaturized Repetitive Transcranial Magnetic Stimulation (rTMS) Head Coils"],"prefix":"10.3390","volume":"24","author":[{"given":"Shaghayegh","family":"Abbasi","sequence":"first","affiliation":[{"name":"Electrical Engineering Department, University of Portland, Portland, OR 97203, USA"}]},{"given":"Sravya","family":"Alluri","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA 92093, USA"},{"name":"Calit2 Advanced Circuits Laboratory, University of California San Diego, La Jolla, CA 92093, USA"}]},{"given":"Vincent","family":"Leung","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Baylor University, Waco, TX 76706, USA"}]},{"given":"Peter","family":"Asbeck","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA 92093, USA"},{"name":"Calit2 Advanced Circuits Laboratory, University of California San Diego, La Jolla, CA 92093, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0507-5883","authenticated-orcid":false,"given":"Milan T.","family":"Makale","sequence":"additional","affiliation":[{"name":"Moores Cancer Center, Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA 92093, USA"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1016\/j.neuron.2007.06.026","article-title":"Transcranial Magnetic Stimulation: A Primer","volume":"55","author":"Hallett","year":"2007","journal-title":"Neuron"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1097\/ADM.0000000000000575","article-title":"A Light in the Darkness: Repetitive Transcranial Magnetic Stimulation (rTMS) to Treat the Hedonic Dysregulation of Addiction","volume":"14","author":"Pettorruso","year":"2020","journal-title":"J. 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