SYSTEM AND METHOD FOR TRACKING MEDICAL DEVICE

• US 20090082665A1
• Filed: 09/26/2007
• Published: 03/26/2009
• Est. Priority Date: 09/26/2007
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Anderson, Peter
• Application Number:
  US11/861,537
• Publication Number:
  US 20090082665A1
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 2017/00725 Calibration or performance testing
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/062 using magnetic field

Abstract

In one embodiment, a method of detecting a distortion is provided. The method comprises steps of identifying a change in transmitter gain for a first transmitter coil, identifying a change in transmitter gain for a second transmitter coil, comparing the change in transmitter gain for the first transmitter coil with the change in transmitter gain for the second transmitter coil and identifying a first condition upon determining that the change in transmitter gain for the first transmitter coil is different from the change in transmitter gain for the second transmitter coil.

Claims

1. A tracking system comprising:

a transmitter assembly comprising at least one transmitter coil configured to emit a signal;

a receiver assembly comprising at least one receiver coil configured for receiving the signal from the transmitter assembly, the signal representing position information comprising at least one of position and orientation of the transmitter assembly;

a distortion detection unit for detecting an impact of distortion from an object on the signal; and

a tracker electronics coupled to the receiver assembly and the distortion detection unit, the tracker electronics configured for determining the position of the transmitter assembly based on the signal received by the receiver assembly and impact of distortion.

2. The tracking system of claim 1, further comprises a display for displaying the position of the transmitter assembly.

3. The tracking system of claim 2, wherein the position information is determined based on a mutual inductance between the transmitter coil and the receiver coil.

4. The tracking system of claim 2, wherein the position information is determined based on the signal and a gain ratio for the receiver assembly.

5. The tracking system of claim 3, wherein each of the transmitter coil and the receiver coil is operable to generate and/or sense an electromagnetic field.

6. The tracking system of claim 1, wherein the transmitter assembly is coupled to one of a medical object, a surgical table, a medical device or a surgical implant.

7. The tracking system of claim 1, wherein the receiver assembly is coupled to one of a medical object, a surgical table, a medical device or a surgical implant.

8. The tracking system of claim 1, wherein the receiver assembly is integrated with the tracker electronics.

9. A method of detecting a distortion, the method comprising:

identifying a change in transmitter gain for a first transmitter coil 505;

identifying a change in transmitter gain for a second transmitter coil 510;

comparing the change in transmitter gain for the first transmitter coil 505 with the change in transmitter gain for the second transmitter coil 510; and

identifying a first condition upon determining that the change in transmitter gain for the first transmitter coil 505 is different from the change in transmitter gain for the second transmitter coil 510.

10. The method of claim 9, further comprises identifying a second condition upon determining that the change in transmitter gain for the first transmitter coil 505 is approximately equal to the change in transmitter gain for the second transmitter coil 510.

11. The method of claim 9, wherein the first condition is a field distortion condition.

12. The method of claim 10, wherein the second condition is a low battery condition.

13. The method of claim 9, wherein identifying a change in the transmitter gain comprises steps of:

obtaining a first magnetic moment of a transmitter coil, the first magnetic moment corresponding to a first predetermined time period;

obtaining a second magnetic moment of the transmitter coil, the second magnetic moment corresponding to a second predetermined time period;

comparing the first magnetic moment corresponding to the first predetermined time period with the second magnetic moment corresponding to the second predetermined time period; and

tracking a change in the transmitter gain for the transmitter coil upon detecting a difference between the first magnetic moment and the second magnetic moment of the transmitter coil.

14. A method of tracking a position of a medical device, the method comprising:

transmitting a signal from a transmitter assembly located on a medical device;

receiving the signal at a receiver assembly located away from the medical device, the signal representing a position information comprising at least one of position and orientation of the transmitter assembly;

detecting an impact of distortion on the position information; and

determining a position of the transmitter assembly based on the signal received by the receiver assembly and the impact of distortion.

15. The method of claim 14, further comprising displaying the position of the transmitter assembly.

16. The method of claim 14, wherein the method of detecting a distortion comprises:

identifying a change in transmitter gain for the first transmitter coil 505;

identifying a change in transmitter gain for the second transmitter coil 510;

comparing the change in transmitter gain for the first transmitter coil 505 with the change in transmitter gain for the second transmitter coil 510; and

identifying a first condition upon determining that the change in transmitter gain for the first transmitter coil 505 is different from the change in transmitter gain for the second transmitter coil 510.

17. The method of claim 16, further comprises identifying a second condition upon determining that the change in transmitter gain for the first transmitter coil 505 is approximately equal to the change in transmitter gain for the second transmitter coil 510.

18. The method of claim 16, wherein the first condition is a field distortion condition.

19. The method of claim 17, wherein the second condition is a low battery condition.

20. The method of claim 16, wherein identifying a change in the transmitter gain comprises steps of:

obtaining a first magnetic moment of a transmitter coil, the first magnetic moment corresponding to a first predetermined time period;

obtaining a second magnetic moment of the transmitter coil, the second magnetic moment corresponding to a second predetermined time period;

comparing the first magnetic moment corresponding to the first predetermined time period with the second magnetic moment corresponding to the second predetermined time period; and

tracking a change in the transmitter gain for the transmitter coil upon detecting a difference between the first magnetic moment and the second magnetic moment.

21. A method of tracking a transmitter coil, the method comprising:

obtaining a first magnetic moment of the transmitter coil, the first magnetic moment corresponding to a first predetermined time period;

obtaining a second magnetic moment of the transmitter coil, the second magnetic moment corresponding to a second predetermined time period;

comparing the first magnetic moment corresponding to the first predetermined time period with the second magnetic moment corresponding to the second predetermined time period;

tracking a change in the magnetic moment of the transmitter coil upon detecting a difference between the first magnetic moment and the second magnetic moment; and

determining the presence of one of a first condition and a second condition upon tracking a change in the magnetic moment.

22. The method of claim 21, wherein the first condition is a field distortion condition.

23. The method of claim 21, wherein the second condition is a low battery condition.