# US 2019/0170837 A1 · Tunable rf coil for magnetic resonance imaging > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170837 A1 - Document ID: US20190170837A1 - Status: Published application - Kind: A1 - Application number: 16/324,594 - Filed: 2017-08-16 - Published: 2019-06-06 - Earliest claimed: 2016-08-18 - Assignees: Koninklijke Philips N.V. - Applicants: Koninklijke Philips N.V. - Inventors: CHRISTIAN FINDEKLEE; CHRISTOPH LEUSSLER - Web page: https://patentgrep.com/patent/US20190170837A1 ## CPC - G01R 33/34069: {Saddle coils} - G01R 33/34007: {Manufacture of RF coils, e.g. using printed circuit board technology; additional hardware for providing mechanical support to the RF coil assembly or to part thereof, e.g. a support for moving the coil assembly relative to the remainder of the MR system} - G01R 33/34046: {Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils} - G01R 33/3628: {Tuning/matching of the transmit/receive coil} - G01R 33/422: of the radio frequency field - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The invention concerns to a radio frequency (RF) body coil (2), for use in a Magnetic Resonance Imaging (MRI) system, comprising: an RF shield (6), an RF coil element (8), distantly arranged from the RF shield (6), and at least one distance setting element (10), arranged and designed in such a way that the relative distance (12) between the RF shield (6) and the RF coil element (8) is adjustable via the distance setting element (10) which may lead to locally deforming the RF coil element (8) and/or the RF shield (6). Thus, a radio frequency coil for use in an Magnetic Resonance Imaging system is provided that can be tuned to desired resonances in a comfortable and economic way. ## Claims ### Claim 1 A radio frequency (RF) body coil, for use in an Magnetic Resonance Imaging (MRI) system, comprising: an RF shield, an RF coil element, distantly arranged from the RF shield, and at least one distance setting element, arranged and designed in such a way that the relative distance between the RF shield and the RF coil element is locally adjustable via the distance setting element by locally deforming the RF coil element and/or the RF shield, wherein the distance setting element is configured to mechanically connect the RF coil element and the RF shield to each other. ### Claim 2 (depends on 1) The RF body coil according to claim 1, wherein the distance setting element is configured as at least one selected from a group consisting of a screw mechanism, a fixation band and an eccentric screw. ### Claim 3 (depends on 1) The RF body coil according to claim 1, wherein the distance setting element is connectable to the RF coil element, the RF shield comprises a feed through aperture arranged in radial direction of the RF shield and the distance setting element is fed through the aperture. ### Claim 4 (depends on 2) The RF body coil according to claim 2, wherein the distance setting element is configured as a fixation band, wherein in a cross-sectional area in a direction perpendicular to the longitudinal axis of a cylindrically arranged RF body coil, the RF shield comprises first connection elements, on a shield surface facing the RF coil element, the RF coil element comprises second connection elements, preferably equidistantly spaced to each other, the first connection elements and the second connections elements are arranged aligned to each other or with an offset to each other, the fixation band is connected between the first connection elements and the second connection elements, and the length of the fixation band is adjustable via the second connections elements. ### Claim 5 (depends on 1) The RF body coil according to claim 1, wherein the RF body coil comprises a plurality of distance setting elements. ### Claim 6 (depends on 1) The RF body coil according to claim 1, further comprising a flexible layer at least partially disposed between the RF coil element and the RF shield. ### Claim 7 (depends on 1) The RF body coil according to claim 1, further comprising a solid coil former, wherein the RF shield r the RF coil element is arranged on the coil former. ### Claim 8 (depends on 6) The RF coil according to claim 6, wherein the coil former comprises an inner surface and an outer surface, and the inner surface is averted to the outer surface, wherein when the RF body coil is arranged in an MRI-system the inner surface faces the center of a patient tunnel of the MRI-system, wherein: the RF coil element is arranged on the outer surface of the coil former, the flexible layer is arranged on the RF coil element, wherein the RF coil element is positioned between the coil former and the flexible layer, and the RF shield is arranged on the flexible layer. ### Claim 9 (depends on 6) The RF coil according to claim 6, wherein the coil former comprises an inner surface and an outer surface, and the inner surface is averted to the outer surface, wherein when the RF body coil is arranged in an MRI-system the inner surface faces the center of a patient tunnel of the MRI-system, wherein: the RF shield is mounted on the outer surface of the coil former, the flexible layer is arranged on the inner surface of the coil former, and the RF coil element is arranged on the flexible layer, wherein the flexible layer is disposed between the RF coil element and the coil former. ### Claim 10 (depends on 1) The RF coil according to claim 1, wherein the RF coil element comprises a resonator element or a plurality of electrically conducting strips. ### Claim 11 (depends on 1) The RF coil according to claim 1, wherein the RF coil element is formed as a birdcage coil comprising two circular conductive loops connected by a number of conductive straight elements and using capacitive structures to form a resonator. ### Claim 12 (depends on 1) The RF coil according to claim 1, wherein the RF coil element is formed as a transverse electromagnetic (TEM) resonator coil. ### Claim 13 A method for tuning a radio frequency (RF) body coil, wherein the RF body coil includes an RF shield, an RF coil element, distantly arranged from the RF shield, and at least one distance setting element, arranged and designed in such a way that the relative distance between the RF shield and the RF coil element is locally adjustable via the distance setting element by locally deforming the RF coil element and/or the RF shield, wherein the distance setting element is configured to mechanically connect the RF coil element and the RF shield to each other, wherein the RF body coil is arranged in a MRI system, the method comprises: measuring the frequency of the RF coil element and/or the homogeneity of the RF field; and adjusting the distance between the RF coil element and the RF shield via the distance setting elements by locally deforming the RF coil element and/or the RF shield. ### Claim 14 (canceled) ### Claim 15 (depends on 4) The RF body coil of claim 4, wherein the first connection elements equidistantly spaced relative to each other. ### Claim 16 (depends on 10) The RF coil of claim 10, wherein the resonator element is a pcb-based resonator.