{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:18:44Z","timestamp":1760242724907,"version":"build-2065373602"},"reference-count":19,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2016,4,21]],"date-time":"2016-04-21T00:00:00Z","timestamp":1461196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper reports on a micro saddle coil for local high-resolution magnetic resonance imaging (MRI) fabricated by embedding a flexible coil pattern into a polydimethyilsiloxane (PDMS) tube. We can change the sensitivity of the micro coil by deforming the shape of the coil from a saddle-shaped mode to a planar-shaped mode. The inductance, the resistance, and the Q-factor of the coil in the saddle-shaped mode were 2.45 \u03bcH, 3.31 \u03a9, and 39.9, respectively. Those of the planar-shaped mode were 3.07 \u03bcH, 3.92 \u03a9, and 42.9, respectively. In MRI acquired in saddle-shaped mode, a large visible area existed around the coil. Although the sensitive area was considerably reduced in the planar-shaped mode, clear MRI images were obtained. The signal-to-noise ratios (SNR) of the saddle-shaped and planar-shaped modes were 194.9 and 505.9, respectively, at voxel size of 2.0 \u00d7 2.0 \u00d7 2.0 mm3 and 11.7 and 37.4, respectively, at voxel size of 0.5 \u00d7 0.5 \u00d7 1.0 mm3. The sensitivity of the saddle-shaped and the planar-shaped modes were about 3 times and 10 times higher, respectively, than those of the medical head coil at both voxel sizes. Thus, the micro saddle coil enabled large-area imaging and highly sensitive imaging by switching the shape of the coil.<\/jats:p>","DOI":"10.3390\/mi7040067","type":"journal-article","created":{"date-parts":[[2016,4,21]],"date-time":"2016-04-21T10:25:21Z","timestamp":1461234321000},"page":"67","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Micro Saddle Coil with Switchable Sensitivity for Local High-Resolution Imaging of Luminal Tissue"],"prefix":"10.3390","volume":"7","author":[{"given":"Tetsuji","family":"Dohi","sequence":"first","affiliation":[{"name":"Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan"}]},{"given":"Kousuke","family":"Murashige","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2016,4,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"831","DOI":"10.1097\/00006123-199710000-00013","article-title":"Development and implementation of intraoperative magnetic resonance imaging and its neurosurgical applications","volume":"41","author":"Black","year":"1997","journal-title":"Neurosurgery"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"129","DOI":"10.2463\/mrms.4.129","article-title":"Intelligent operation theater using intraoperative open-MRI","volume":"4","author":"Iseki","year":"2005","journal-title":"Magn. 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