Electronic valve reader

• US 7,334,582 B2
• Filed: 10/31/2003
• Issued: 02/26/2008
• Est. Priority Date: 10/31/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Morris, Dan, Golden, Robert, Speckman, Lori C., Bertrand, William J., Sanders, Gary, Vincent, Steve
• Primary Examiner(s): Gilbert; Samuel G
• Application Number:
  US10/698,095
• Publication Number:
  US 20050092335A1
• Time in Patent Office: 1,579 Days
• Field of Search: 600/12, 128897-899, 32420711-20717, 324/207.26, 324/228, 324/231, 324/326, 324/329, 324/345, 324/347, 324/348, 604 8- 10, 604247-248
• US Class Current: 128/899
• 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: A61M 27/006 Cerebrospinal drainage; Accessories therefor, e.g. valves

Abstract

The invention is directed toward a magnetic valve reader used as an indicator tool. The magnetic valve reader determines a location and an orientation for a magnetic indicator device to indicate a device setting of an implantable medical device. The implantable medical device includes the magnetic indicator device coupled to a valve on the implantable medical device. External magnetic fields, specifically the Earth'"'"'s magnetic field, may interfere with the compass and create an incorrect device setting indication. The electronic reader estimates the external magnetic fields to subtract the estimate from received data to minimize any influence that external magnetic field has on the accuracy of the device setting measurement.

Claims

1. An electronic magnetic-based indicator tool comprising:

a housing having an electronic display;

a plurality of magnetic field sensors, the plurality of magnetic field sensors grouped into sets of magnetic field sensors to determine spatial location and orientation of a magnetic indicator device associated with a valve of an implantable flow control device; and

a processing module that receives magnetic data values from the plurality of magnetic field sensors and determines a setting for the valve on the implantable flow control device using the determined orientation of the magnetic indicator device.

2. The electronic magnetic-based indicator tool according to claim 1, wherein the processing module further determines the setting of the valve on the implantable flow control device using a determined orientation of a reference magnet coupled to the implantable flow control device at a location separate from the magnetic indicator device.

3. The electronic magnetic-based indicator tool according to claim 1, wherein the processing module generates a display image corresponding to an orientation of the valve relative to the implantable flow control device and outputs the display image on the electronic display.

4. The electronic magnetic-based indicator tool according to claim 1, wherein the processing module determines an estimate for ambient magnetic fields from a sequence of magnetic data values from the plurality of magnetic field sensors.

5. The electronic magnetic-based indicator tool according to claim 4, wherein the processing module further subtracts the estimate for ambient magnetic fields from received magnetic data values to determine the setting of the valve on the implantable flow control device.

6. The electronic magnetic-based indicator tool of claim 1, wherein the plurality of magnetic field sensors comprises four sets of three sensors for determining location and orientation of the magnetic indicator device in five degrees of freedom.

7. The electronic magnetic-based indicator tool of claim 6, wherein each of the four sets of three sensors being located about a respective one of four corners of the indicator tool.

8. The electronic magnetic-based indicator tool according to claim 1, wherein the indicator tool further comprises an adjustment tool that modifies an orientation of the valve in the implantable flow control device.

9. The electronic magnetic-based indicator tool according to claim 8, wherein the adjustment tool comprises a magnetic adjustment component that magnetically couples to the magnetic indicator device of the flow control device.

10. The electronic magnetic-based indicator tool according to claim 9, wherein rotating the adjustment tool while the magnetic adjustment component is magnetically coupled to the magnetic indicator device of the flow control device causes the valve of the flow control device to rotate changing the setting of the valve.

11. The electronic magnetic-based indicator tool according to claim 1, wherein the tool further comprises:

a removable data storage device, the data storage device containing computer readable data that translates the setting of the valve to a pressure for the implantable flow control device.

12. The electronic magnetic-based indicator tool according to claim 11, wherein the removable storage device being from a group of removable data storage devices consisting of compact flash memory device, a secure digital memory device, a smart media storage device, and a memory stick memory device.

13. The electronic magnetic-based indicator tool according to claim 11, wherein computer readable data that translates the setting of the valve to the pressure for the implantable flow control device corresponds to a particular model of the implantable flow control device.

14. The electronic magnetic-based indicator tool according to claim 11, wherein the indicator tool further comprises user controls that activate operation of the tool and a power supply.

15. The electronic magnetic-based indicator tool according to claim 14, wherein the power supply comprises a removable battery.

16. A system comprising:

an implantable medical device comprising a magnetic indicator device associated with a valve of an implantable flow control device that indicates a current setting of the implantable flow control device;

an electronic magnetic-based indicator tool comprising;

a housing having an electronic display;

a plurality of magnetic field sensors, the plurality of magnetic field sensors grouped into sets of three magnetic field sensors; and

a processing module that receives magnetic data values from the plurality of magnetic field sensors and determines a setting for the valve on the implantable flow control device using a determined orientation of the magnetic indicator device coupled to the valve; and

an adjustment tool that modifies an orientation of the valve in the implantable flow control device, the adjustment tool comprises a magnetic adjustment component for magnetically coupling to the magnetic indicator device of the flow control device.

17. The system according to claim 16, wherein the processing module further determines the setting of the valve on the implantable flow control device using a determined orientation of a reference magnet coupled to the implantable flow control device at a location separate from the magnetic indicator device.

18. The system according to claim 16, wherein the processing module generates a display image corresponding to the setting of the implantable flow control device and outputs the display image on the electronic display.

19. The system according to claim 16, wherein the processing module determines an estimate for ambient magnetic fields from a sequence of magnetic data values from the plurality of magnetic field sensors.

20. The system according to claim 19, wherein the processing module further subtracts the estimate for ambient magnetic fields from received magnetic data values to determine the setting of the valve on the implantable flow control device.

21. The system according to claim 16, wherein the tool further comprises:

a removable data storage device, the data storage device containing computer readable data that translates the setting of the valve to pressure for the implantable flow control device.

22. The system according to claim 21, wherein the removable storage device being from a group of removable data storage devices consisting of compact flash memory device, a secure digital memory device, a smart media storage device, and a memory stick memory device.

23. The system according to claim 21, wherein computer readable data that translates the setting of the valve to pressure for the implantable flow control device corresponds to a particular model of the implantable flow control device.

24. The system according to claim 21, wherein the indicator tool further comprises user controls that activate operation of the tool and a power supply.

25. The system according to claim 24, wherein the power supply comprises a removable battery.

26. A method comprising:

placing an electronic magnetic-based indicator tool adjacent to an implantable medical device, the implantable medical device having a magnetic indicator device coupled to a valve used to control operation of the medical device;

measuring a magnetic field strength observed by the indicator tool;

estimating a portion of the observed magnetic fields caused by an environmental magnetic field;

determining an orientation of the magnetic indicator device relative to a known position of the implantable medical device using the observed magnetic field and the estimate for the environmental magnetic field; and

indicating a device setting of the implantable medical device.

27. The method according to claim 26, wherein the known position of the implantable medical device is determined from an expected orientation of the indicator tool relative to the implantable medical device.

28. The method according to claim 26, wherein the known position of the implantable medical device is determined from determining a location and orientation of a reference magnetic device coupled to the implantable medical device.

29. The method according to claim 26, wherein the measuring the magnetic field comprises:

receiving electronic signals from a plurality of magnetic field sensors, the magnetic field sensors grouped into a plurality of sets of three sensors located at separate locations within the indicator tool; and

processing the received electronic signals to determine an orientation and location of a magnetic device.

30. The method according to claim 29, wherein the plurality of sets of three sensors comprise four sets of sensors, each of the four sets of sensors being located about a respective one of four corners of the indicator tool.