MRI Safety System

• US 20120112747A1
• Filed: 11/09/2010
• Published: 05/10/2012
• Est. Priority Date: 11/09/2010
• Status: Active Grant

• Current Assignee: Deerfield Imaging Incorporated
• Original Assignee: IMRIS Inc.
• Inventors: Fallah-Rad, Mehran, Scarth, Gordon, Hushek, Stephen G., Alexiuk, Mark, Champagne, Kirk Maurice, Hoeppner, Timothy James, Weber, David John Robert
• Granted Patent: US 8,901,928 B2
• Time in Patent Office: Days
• US Class Current: 324/318
• CPC Class Codes: G01R 33/288 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

Abstract

In a MRI system housed within a room there is provided a movable magnet and additional components for other procedures on the patient, a control system is provided for the relative movement of the magnet and components. This includes a plurality of magnetic field sensors mounted on the components for measuring the magnetic field at the location of the component and an optional camera positioning system so that the control system can estimate relative positions of the components relative to the magnet from the sensed field strengths from the set of sensors to avoid collisions during the movements.

Claims

1. Apparatus for carrying out medical procedures on a patient comprising:

a magnetic resonance imaging apparatus including a magnet for generating a magnetic field of sufficient intensity to carry out a magnetic resonance imaging procedure on the patient;

a plurality of additional components for use in carrying out at least one additional procedure on the patient;

wherein the field of the magnet extends to an area outside of the magnet with sufficient intensity to cause movement of ferro-magnetic material within the area;

the magnet and/or the plurality of additional components being mounted for relative movement such that the magnetic resonance imaging procedure is carried out with the plurality of additional components in a remote location from the magnet and the at least one additional procedure is carried out with the magnet in a remote location from the plurality of additional components;

a control system for controlling the relative movement of the magnet and the plurality of additional components;

a plurality of magnetic field sensors each mounted on a respective one of the plurality of additional components for measuring the magnetic field at the location of the component;

the magnetic field sensors being arranged for communication of signals to the control system;

the control system being arranged to change operation of the relative movement of the magnet and/or the components in response to receipt of a signal from one or more of the sensors.

2. The apparatus according to claim 1 wherein each sensor measures the magnetic field strength in 3 perpendicular dimensions.

3. The apparatus according to claim 1 wherein the magnetic field sensors are mounted on mobile and stationary objects such as booms, a surgical table, microscopes, instrument trays, kick buckets, foot pedals.

4. The apparatus according to claim 1 wherein the magnetic field sensors communicate by wireless communication from the sensors to the control system.

5. The apparatus according to claim 1 wherein the control system includes an audio/visual display.

6. The apparatus according to claim 1 wherein the control system includes a real-time asset tracking system for the components.

7. The apparatus according to claim 1 wherein the control system is arranged to initiate movement of components from a potentially unsafe position to a pre-defined safe-position.

8. The apparatus according to claim 1 wherein the control system includes object avoidance mechanisms in order to avoid collision with persons and other objects in the room.

9. The apparatus according to claim 1 wherein the control system is arranged to estimate position of the magnet from the sensed field strengths from the set of sensors.

10. The apparatus according to claim 9 wherein the control system is arranged to use information on the estimated position of the magnet to anticipate collisions and initiate avoidance mechanisms.

11. The apparatus according to claim 1 wherein the control system is arranged to include a known position of the sensor on the object and a physical model of the object extension so as to provide a decision based on the current orientation of the object and the sensed field strength.

12. The apparatus according to claim 1 wherein there are provided objects in the area which do not have magnetic field sensors attached to them but have positions communicated to the control system.

13. The apparatus according to claim 12 wherein the objects are fixed.

14. The apparatus according to claim 12 wherein the objects have their position measured or inferred by other means, such as a camera system.

15. The apparatus according to claim 1 wherein the control system is arranged to achieve an optimal configuration of the components for imaging.

16. The apparatus according to claim 1 wherein the control system is arranged to shut off RF noisy equipment before imaging.

17. Apparatus for carrying out medical procedures on a patient comprising:

a magnetic resonance imaging apparatus including a magnet for generating a magnetic field of sufficient intensity to carry out a magnetic resonance imaging procedure on the patient;

a plurality of additional components for use in carrying out at least one additional procedure on the patient;

wherein the field of the magnet extends to an area outside of the magnet with sufficient intensity to cause movement of ferro-magnetic material within the area;

the magnet being mounted for movement relative to the patient from a first position for the magnetic resonance imaging procedure on the patient to a second remote position for carrying out the additional procedure on the patient;

a control system for controlling the movement of the magnet;

and a plurality of magnetic field sensors each mounted on a respective one of the plurality of additional components for measuring the magnetic field at the location of the component;

the magnetic field sensors being arranged for communication of signals to the control system.

18. The apparatus according to claim 17 wherein the control system is arranged to stop movement of the magnet.

19. Apparatus for carrying out medical procedures on a patient comprising:

a magnetic resonance imaging apparatus including a magnet for generating a magnetic field of sufficient intensity to carry out a magnetic resonance imaging procedure on the patient;

a plurality of additional components for use in carrying out at least one additional procedure on the patient;

wherein the field of the magnet extends to an area outside of the magnet with sufficient intensity to cause movement of ferro-magnetic material within the area;

the magnet and/or the plurality of additional components being mounted for relative movement such that the magnetic resonance imaging procedure is carried out with the plurality of additional components in a remote location from the magnet and the at least one additional procedure is carried out with the magnet in a remote location from the plurality of additional components;

a control system for controlling the relative movement of the magnet and the plurality of additional components;

a plurality of magnetic field sensors each mounted on a respective one of the plurality of additional components for measuring the magnetic field at the location of the component;

the magnetic field sensors being arranged for communication of signals to the control system;

wherein the control system is arranged to estimate relative positions of the components relative to the magnet from the sensed field strengths from the set of sensors.