Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI
Nowadays, MRI is focused on using ultra-high static magnetic fields (>7 T) to increase the signal-to-noise ratio. The use of high fields, on the other hand, requires novel technical solutions as well as more stringent design criteria for specific absorption rate levels, reducing radiative...
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| Format: | Article |
| Language: | English |
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IEEE
2022-01-01
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| Series: | IEEE Access |
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| Online Access: | https://ieeexplore.ieee.org/document/9903425/ |
| _version_ | 1811344649149743104 |
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| author | Nicola Curreli Matteo Bruno Lodi Andrea Melis Claudio Puddu Sergio Casu Alessandro Fanti Nikola Djuric Alessandra Retico Giuseppe Mazzarella |
| author_facet | Nicola Curreli Matteo Bruno Lodi Andrea Melis Claudio Puddu Sergio Casu Alessandro Fanti Nikola Djuric Alessandra Retico Giuseppe Mazzarella |
| author_sort | Nicola Curreli |
| collection | DOAJ |
| description | Nowadays, MRI is focused on using ultra-high static magnetic fields (>7 T) to increase the signal-to-noise ratio. The use of high fields, on the other hand, requires novel technical solutions as well as more stringent design criteria for specific absorption rate levels, reducing radiative effect and coil resistance. In this paper, two flexible RF coils for 7 T human magnetic resonance, and 298 MHz ultra-high frequency operations were analyzed and characterized. Imaging of lower human limbs is regarded as a case study. The lumped element theory and subsequent numerical simulations were used to fine-tune the single-coil element and the dual-coil array design, respectively. Here, we demonstrate how the shape, size, configuration, and presence of the sample influence the coil performance. The penetration depth of the <inline-formula> <tex-math notation="LaTeX">$B_{1}$ </tex-math></inline-formula>-field and the specific absorption rate values have been determined numerically using two numerical surface phantoms: saline and a multilayer human tissue. A preliminary study in the presence of a saline solution phantom has been carried out to develop and validate the dual-coil system. The frequency response of the dual-coil array was measured to assess its robustness when coupled to twelve human volunteers. We found that our design is robust to variations in the anatomical properties of the human thighs, and hence to coil bending. The presented approach can be useful for the implementation of flexible devices with high sensitivity levels and low specific absorption rate. |
| first_indexed | 2024-04-13T19:50:17Z |
| format | Article |
| id | doaj.art-ac3e5a1f50494c6381b4552094aad3b7 |
| institution | Directory Open Access Journal |
| issn | 2169-3536 |
| language | English |
| last_indexed | 2024-04-13T19:50:17Z |
| publishDate | 2022-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj.art-ac3e5a1f50494c6381b4552094aad3b72022-12-22T02:32:34ZengIEEEIEEE Access2169-35362022-01-011010458910459710.1109/ACCESS.2022.32096769903425Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRINicola Curreli0https://orcid.org/0000-0002-5786-8885Matteo Bruno Lodi1https://orcid.org/0000-0002-8314-1575Andrea Melis2https://orcid.org/0000-0002-4372-0337Claudio Puddu3https://orcid.org/0000-0003-1444-3112Sergio Casu4Alessandro Fanti5https://orcid.org/0000-0001-6218-881XNikola Djuric6https://orcid.org/0000-0002-7174-3499Alessandra Retico7Giuseppe Mazzarella8https://orcid.org/0000-0002-1429-9600Functional Nanosystems, Istituto Italiano di Tecnologia, Genova, ItalyDepartment of Electrical and Electronic Engineering, University of Cagliari, Cagliari, ItalyDepartment of Electrical and Electronic Engineering, University of Cagliari, Cagliari, ItalyDepartment of Infection, Immunity and Cardiovascular Disease, POLARIS, University of Sheffield, Sheffield, U.K.Department of Electrical and Electronic Engineering, University of Cagliari, Cagliari, ItalyDepartment of Electrical and Electronic Engineering, University of Cagliari, Cagliari, ItalyDepartment of Power, Electronic and Telecommunication Engineering, Faculty of Technical Sciences, University of Novi Sad, Novi Sad, SerbiaINFN-CA, Complesso Universitario di Monserrato, Cagliari, ItalyDepartment of Electrical and Electronic Engineering, University of Cagliari, Cagliari, ItalyNowadays, MRI is focused on using ultra-high static magnetic fields (>7 T) to increase the signal-to-noise ratio. The use of high fields, on the other hand, requires novel technical solutions as well as more stringent design criteria for specific absorption rate levels, reducing radiative effect and coil resistance. In this paper, two flexible RF coils for 7 T human magnetic resonance, and 298 MHz ultra-high frequency operations were analyzed and characterized. Imaging of lower human limbs is regarded as a case study. The lumped element theory and subsequent numerical simulations were used to fine-tune the single-coil element and the dual-coil array design, respectively. Here, we demonstrate how the shape, size, configuration, and presence of the sample influence the coil performance. The penetration depth of the <inline-formula> <tex-math notation="LaTeX">$B_{1}$ </tex-math></inline-formula>-field and the specific absorption rate values have been determined numerically using two numerical surface phantoms: saline and a multilayer human tissue. A preliminary study in the presence of a saline solution phantom has been carried out to develop and validate the dual-coil system. The frequency response of the dual-coil array was measured to assess its robustness when coupled to twelve human volunteers. We found that our design is robust to variations in the anatomical properties of the human thighs, and hence to coil bending. The presented approach can be useful for the implementation of flexible devices with high sensitivity levels and low specific absorption rate.https://ieeexplore.ieee.org/document/9903425/Coilsoptimizationflexible printed circuitsmagnetic resonance imagingphantoms |
| spellingShingle | Nicola Curreli Matteo Bruno Lodi Andrea Melis Claudio Puddu Sergio Casu Alessandro Fanti Nikola Djuric Alessandra Retico Giuseppe Mazzarella Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI IEEE Access Coils optimization flexible printed circuits magnetic resonance imaging phantoms |
| title | Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI |
| title_full | Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI |
| title_fullStr | Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI |
| title_full_unstemmed | Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI |
| title_short | Analysis of a Flexible Dual-Channel Octagonal Coil System for UHF MRI |
| title_sort | analysis of a flexible dual channel octagonal coil system for uhf mri |
| topic | Coils optimization flexible printed circuits magnetic resonance imaging phantoms |
| url | https://ieeexplore.ieee.org/document/9903425/ |
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