Magnetic resonance device, magnetic resonance system and associated operating method

Patent metadata

Field	Value
Publication number	US-11047939-B2
Application number	US-201916529049-A
Country	US
Kind code	B2
Filing date	Aug 1, 2019
Priority date	Aug 1, 2018
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

A magnetic resonance device comprising a gradient coil assembly having gradient coils is described. The gradient coils are supported by at least one cylindrical coil carrier for generating gradient fields. As part of the gradient coil assembly, at least one vibration sensor is provided for measuring vibrations of the gradient coil assembly at least in a radial direction of oscillation.

First claim

What is claimed is:

1. A magnetic resonance device, comprising:
a gradient coil assembly including:
gradient coils configured to generate gradient fields;
at least one cylindrical coil body configured to support the gradient coils; and
at least one vibration sensor configured to measure vibrations of the gradient coil assembly at least in a radial direction of oscillation, the at least one vibration sensor being disposed in, or on, the gradient coil assembly; and

a control device configured to analyze sensor data acquired from the at least one vibration sensor,
wherein the control device is configured to analyze the sensor data as part of a modal analysis to determine at least one characteristic of at least one measured oscillation including one or more of (i) a frequency, (ii) a frequency spectrum, (iii) harmonic information, (iv) a phase angle between two oscillation components, (v) a time constant, and (vi) a spatial relationship value, and
wherein the control device is further configured to analyze the sensor data to perform at least one of (i) training at least one artificial intelligence algorithm related to at least one correlation, (ii) monitoring the safety of the magnetic resonance device on the basis of the sensor data, (iii) analyzing the sensor data to adjust acquisition parameters of the magnetic resonance device to compensate for current and/or predicted effects of the gradient coil operation, (iv) preventing the occurrence of previously measured effects of the gradient coil operation, and (v) initiating preventive maintenance.

2. The magnetic resonance system, comprising:
a magnetic resonance device having a gradient coil assembly including:
gradient coils configured to generate gradient fields;
at least one cylindrical coil body configured to support the gradient coils; and
at least one vibration sensor configured to measure vibrations of the gradient coil assembly at least in a radial direction of oscillation,

wherein the at least one vibration sensor is disposed in, or on, the gradient coil assembly; and
an external control device that is external to the magnetic resonance device
configured to analyze sensor data acquired from the at least one vibration sensor

wherein the external control device is configured to analyze the sensor data as part of a modal analysis to determine at least one characteristic of at least one measured oscillation including one or more of (i) a frequency, (ii) a frequency spectrum, (iii) harmonic information, (iv) a phase angle between two oscillation components, (v) a time constant, and (vi) a spatial relationship value, and
wherein the external control device is further configured to analyze the sensor data to perform at least one of (i) training at least one artificial intelligence algorithm related to at least one correlation, (ii) monitoring the safety of the magnetic resonance device on the basis of the sensor data, (iii) analyzing the sensor data to adjust acquisition parameters of the magnetic resonance device to compensate for current and/or predicted effects of the gradient coil operation, (iv) preventing the occurrence of previously measured effects of the gradient coil operation, and (v) initiating preventive maintenance.

3. A method for operating a magnetic resonance device, comprising:
providing a gradient coil assembly including (i) gradient coils for generating gradient fields, (ii) at least one cylindrical coil body configured to support the gradient coils, (iii) at least one vibration sensor configured to measure vibrations of the gradient coil assembly at least in a radial direction of oscillation, the at least one vibration sensor being disposed in, or on, the gradient coil assembly, and (iv) at least one temperature sensor configured to measure a temperature of the gradient coil assembly; and
providing a control device to analyze (i) sensor data acquired from the at least one vibration sensor, and (ii) sensor data acquired from the at least one temperature sensor, to determine at least one assessment quantity describing a mechanical effect and/or an electromagnetic effect of the operation of the gradient coil assembly;
performing, via the control device, real-time compensation of an effect associated with the at least one assessment quantity to adjust at least one operating parameter of the magnetic resonance device;
performing, via the control device, real-time noise suppression in a patient communication device with respect to sound produced by the gradient coil assembly and described by the at least one assessment quantity;
evaluating, via the control device using at least one safety criterion that includes one or more of (i) a degradation in a fatigue strength of the gradient coil assembly or components associated with the gradient coil assembly, (ii) a current risk of damage for at least one component of the magnetic resonance device, and (iii) a hazard to a person under examination; and
upon the at least one safety criterion being met, suspending an imaging operation of the magnetic resonance device.

4. The magnetic resonance device as claimed in claim 1 ,
wherein at least one of the at least one vibration sensors includes a piezoelectric sensor and/or a Micro-Electro-Mechanical System (MEMS) accelerometer.

5. The magnetic resonance device as claimed in claim 4 ,
wherein the piezoelectric sensor and/or the MEMS accelerometer are disposed in the gradient coil assembly in a region of low dynamic magnetic fields.

6. The magnetic resonance device as claimed in claim 1 ,
wherein at least one of the at least one vibration sensors is encapsulated inside the at least one cylindrical coil body.

7. The magnetic resonance device as claimed in claim 1 ,
wherein at least one of the at least one vibration sensors is removably mounted on a surface of the gradient coil assembly via a mounting means.

8. The magnetic resonance device as claimed in claim 7 ,
wherein the at least one mounting means includes a mounting plate comprising at least one screw thread embedded on a surface of the at least one cylindrical coil body of the gradient coil assembly, and
wherein at least one of the at least one vibration sensors is mounted to the mounting plate.

9. The magnetic resonance device as claimed in claim 1 , wherein at least one of the at least one vibration sensors is positioned at least at one end of the at least one cylindrical coil body of the gradient coil assembly.

10. The magnetic resonance device as claimed in claim 1 , further comprising:
a cylindrical patient placement area formed in a main magnet unit and surrounded by the gradient coil assembly,
wherein the gradient coils include three gradient coils, each of the three gradient coils being respectively assigned to one of three orthogonal directions, and
wherein a first of the three orthogonal directions corresponds to a longitudinal direction of the patient placement area.

11. The magnetic resonance device as claimed in claim 10 , wherein, when the at least one vibration sensor includes one vibration sensor, the vibration sensor is arranged in a central plane between planes formed by the longitudinal direction of the patient placement area and a second one of the three orthogonal directions, and
wherein, when the at least one vibration sensor includes at least two vibration sensors, a first one of the at least two vibration sensors is arranged in a central plane between planes formed by the longitudinal direction of the patient placement area and a second one of the three orthogonal directions, and a second one of the at least two vibration sensors is arranged in a central plane between planes formed by the longitudinal direction of the patient pla

Assignees

• Siemens Healthcare Gmbh

Inventors

• Dietz Peter
• Stein Annette
• Krug Andreas
• Popescu Stefan

Classifications

• G01R33/288

  Provisions within MR facilities for enhancing safety during MR, e.g. reduction of the specific absorption rate [SAR], detection of ferromagnetic objects in the scanner room · CPC title

• G01R33/3854

  means for active and/or passive vibration damping or acoustical noise suppression in gradient magnet coil systems · CPC title

• G01H11/08

  using piezoelectric devices · CPC title

• G01R33/56572

  caused by a distortion of a gradient magnetic field, e.g. non-linearity of a gradient magnetic field (G01R33/56509, G01R33/56518, G01R33/56536 take precedence) · CPC title

• G01R33/385 Primary

  using gradient magnetic field coils · CPC title