# US 11,029,379 B2 · Bridge member for a magnetic resonance examination system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,379 B2 - Document ID: US11029379B2 - Status: Granted - Kind: B2 - Application number: 16/483,450 - Filed: 2018-02-06 - Published: 2020-01-09 - Granted: 2021-06-08 - Earliest claimed: 2017-02-14 - Assignees: Koninklijke Philips N.V. - Applicants: Koninklijke Philips N.V. - Inventors: Elwin De Weerdt - Web page: https://patentgrep.com/patent/US11029379B2 ## CPC - G01R 33/387: Compensation of inhomogeneities - G01R 33/4828: {Resolving the MR signals of different chemical species, e.g. water-fat imaging} - G01R 33/28: Details of apparatus provided for in groups G01R33/44 - G01R33/64 - G01R 33/4818: {MR characterised by data acquisition along a specific k-space trajectory or by the temporal order of k-space coverage, e.g. centric or segmented coverage of k-space} - G01R 33/5607: {by reducing the NMR signal of a particular spin species, e.g. of a chemical species for fat suppression, or of a moving spin species for black-blood imaging} - G01R 33/56527: {due to chemical shift effects} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A bridge member containing MR responsive material is provided in an open space between body parts to establish a correspondence between the body parts. The MR responsive material generates magnetic resonance signals in response the RF excitation, so that between the separate body parts via the bridge member magnetic resonance signal are obtained from positions between which there is at most a limited spatial variation of the main magnetic field, so that phase ambiguities between the signals from these positions are avoided. Thus, chemical shift separation, notably water-fat separation though a region-of-interest containing several (both) body parts may rely on a smoothness condition imposed on the spatial distribution of the main magnetic field. This avoids artefacts, such as water-fat swaps when separating water and fat contributions in the reconstructed magnetic resonance image. ## Claims ### Claim 1 A bridge member for use in a magnetic resonance examination system and to establish a correspondence between MR signals from separated body parts of a patient to be examined, the bridge member containing a MR responsive fat-like material that has a magnetic resonance response that in response to RF excitation emits magnetic resonance signals having an appreciable signal-to-noise ratio (SNR) and said response resembles fat-like tissue's magnetic resonance response, wherein the bridge member is formed by a patient support and contains the MR responsive material at least along the surface to face the patient to be examined, such that the separated body parts and the bridge member form a path between the separated body parts along which path the fat-like MR response is emitted. ### Claim 2 A bridge member configured for use in a magnetic resonance examination system and to establish a phase correspondence between magnetic signals emitted from separated body parts of a patient to be examined, the bridge member containing a MR responsive fat-like material that has a magnetic resonance response that in response to RF excitation emits magnetic resonance signals having an appreciable signal-to-noise ratio (SNR) and said response resembles fat-like tissue's magnetic resonance response, wherein the bridge member is formed by a stabilisation bag that is shaped and/or is deformable to keep the separate body parts in position and provide a magnetic signal emitting path connecting the separated body parts. ### Claim 3 A method of using a bridge member in a magnetic resonance examination system to establish a correspondence in a phase of MR signals from separated body parts of a patient to be examined, the method comprising positioning a bridge member comprising a MR responsive fat-like material in response to RF excitation emits magnetic resonance signals having an appreciable signal-to-noise ratio (SNR) such that said response resembles fat-like tissue's magnetic resonance response along a path of the bridge member connecting the separated body parts. ### Claim 4 (depends on 1) The bridge member as claimed in claim 1, wherein the bridge member includes a flexible member configured to be placed on a surface of a patient carrier and be flexibly deformed by weight of the patient to be examined into a shape that contacts or is in close proximity to each of the separated body parts and conforms with surface portions of each of the separated body parts. ### Claim 5 (depends on 1) The bridge member as claimed in claim 1 wherein the MR responsive material is disposed in at least part of (i) an outer layer or (ii) along at least part of the bridge member's outline. ### Claim 6 (depends on 1) The bridge member as claimed in claim 1, wherein the fat-like material consists mainly of saturated —CH2- chains. ### Claim 7 (depends on 1) The magnetic resonance examination system provided with bridge member of claim 1. ### Claim 8 (depends on 1) The bridge member as claimed in claim 1, wherein in water-fat separation imaging, the fat-like material generates a bright fat signal and does not generate a significant water signal. ### Claim 9 (depends on 1) The bridge member as claimed in claim 1, wherein in angiography, a level of generated MR signal from the fat-like material is less than a level of MR signals from blood vessels. ### Claim 10 (depends on 1) The bridge member as claimed in claim 1, wherein magnetic resonance signals across the bridge member between one of the separated body parts and another undergo a phase shift of 2π or less. ### Claim 11 (depends on 2) The bridge member as claimed in claim 2, wherein in water-fat separation imaging, the fat-like material generates a bright fat signal and does not generate a noticeable water signal. ### Claim 12 (depends on 2) The bridge member as claimed in claim 2, wherein in angiography, a level of generated MR signal from the fat-like material is less than a level of MR signals from vessels. ### Claim 13 (depends on 2) The bridge member as claimed in claim 2, wherein magnetic resonance signals across the bridge member between one of the body parts and another undergo a B0 induced phase shift of 2π or less. ### Claim 14 (depends on 3) The method of using the bridge member as claimed in claim 3, further including: generating separate water and fat images of the separated body parts and the bridge member, wherein the bridge member is visible in the fat image forming a path between the separated body parts in the fat image and not in the water image. ### Claim 15 (depends on 3) The method of using the bridge member as claimed in claim 3, further including: from phase shifts along the path from a first of the separated bod parts to a second of the separated body parts, determining a phase correspondence in MR signals from the first and second body parts. ### Claim 16 (depends on 15) The method of using the bridge member as claimed in claim 15, wherein a phase shift across the bridge member between the first and second body parts is 2π or less. ### Claim 17 (depends on 3) The method of using the bridge member as claimed in claim 3, further including: generating angiographic images such that MR signals from vessels are stronger than MR signals from the fat-like material in the bridge member. ### Claim 18 (depends on 3) The method of using the bridge member as claimed in claim 3, wherein the bridge member includes a flexible mattress, and wherein the method further includes: placing the mattress on a patient support, positioning a patient on the mattress such that weight of the patient causes the mattress to deform into conformity with the separated body parts and into a space between the separated body parts forming a path of the fat-like material between the separated body parts.