• About
  • Policies
  • What is open access
  • Library
  • Contact
Advanced search
      View Item 
      •   BUIR Home
      • Scholarly Publications
      • National Magnetic Resonance Research Center (UMRAM)
      • View Item
      •   BUIR Home
      • Scholarly Publications
      • National Magnetic Resonance Research Center (UMRAM)
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.

      A z-gradient array coil with a dedicated active-shielded array coil for MRI

      Thumbnail
      View / Download
      4.7 Mb
      Author(s)
      Takrimi, Manouchehr
      Atalar, Ergin
      Date
      2022-08-02
      Source Title
      Magnetic Resonance in Medicine
      Print ISSN
      0740-3194
      Publisher
      John Wiley and Sons Inc.
      Volume
      88
      Issue
      6
      Pages
      2718 - 2731
      Language
      English
      Type
      Article
      Item Usage Stats
      10
      views
      1
      downloads
      Abstract
      Purpose: An array-based z-gradient coil with a set of programmable power amplifiers can outperform a conventional z-gradient coil and make it highly customizable with a broader range of tunable features. Methods: A dynamically adjustable imaging volume can be achieved using a pair of independent arrays and a modified optimization procedure based on analytic equations. Two modes of operation are provided: (a) standard mode that resembles a conventional coil; (b) advanced mode, where all performance parameters can be adjusted employing a controllable feeding mechanism. Commercial software is used to demonstrate the validity and feasibility of the proposed coil. Results: Primary and shield array diameters are 24 and 30 cm, both of which comprise 12 bundles of 10 turns copper wires. Maximum feeding voltage/current is 250 V/100 A for all array elements. Four distinct magnetic profiles are provided: (a) conventional profile with 140 mm diameter spherical region of interest, 120 mT/m gradient, and up to 4500 T/m/s slew rate; (b) profile of 200 mT/m, 70 mm region of interest, and up to 6900 T/m/s slew rate; (c) 60 mm axially shifted 70 mm region of interest with 120 mT/m strength and 3600 T/m/s slew rate; and (d) profile of 370 mT/m, 120 mm region of interest, and 3700 T/m/s slew rate when the active shield is reverse fed. Conclusion: By using an active-shielded gradient array coil, the magnetic field profile of the imaging volume can be adjusted dynamically, and it can provide new features and a wide range of field profiles for diverse applications in MRI.
      Keywords
      Active shield
      Array coil
      Gradient coil
      Magnetic profile
      Tunable imaging volume
      Permalink
      http://hdl.handle.net/11693/111972
      Published Version (Please cite this version)
      https://dx.doi.org/10.1002/mrm.29390
      Collections
      • Department of Electrical and Electronics Engineering 4011
      • National Magnetic Resonance Research Center (UMRAM) 301
      Show full item record

      Browse

      All of BUIRCommunities & CollectionsTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartmentsCoursesThis CollectionTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartmentsCourses

      My Account

      Login

      Statistics

      View Usage StatisticsView Google Analytics Statistics

      Bilkent University

      If you have trouble accessing this page and need to request an alternate format, contact the site administrator. Phone: (312) 290 2976
      © Bilkent University - Library IT

      Contact Us | Send Feedback | Off-Campus Access | Admin | Privacy