POSITION DETECTING DEVICE, MEDICAL DEVICE GUIDANCE SYSTEM, POSITION DETECTING METHOD, AND MEDICAL DEVICE GUIDING METHOD

• US 20100156399A1
• Filed: 03/05/2010
• Published: 06/24/2010
• Est. Priority Date: 09/07/2007
• Status: Abandoned Application

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Medical Systems Corporation (Olympus Corporation)
• Inventors: TAKAHASHI, Masaki, KAWANO, Hironao, SATO, Ryoji, KIMURA, Atsushi, CHIBA, Atsushi, UCHIYAMA, Akio
• Application Number:
  US12/718,432
• Publication Number:
  US 20100156399A1
• Time in Patent Office: Days
• US Class Current: 324/207.130
• CPC Class Codes: A61B 1/00158 using magnetic field
• CPC Class Codes: A61B 1/041 Capsule endoscopes for imaging
• CPC Class Codes: A61B 2034/732 arranged around the patient, e.g. in a gantry
• 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 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: G01B 7/004 for measuring coordinates of points

Abstract

A position detecting device includes a detected object that includes a circuit with an internal coil; a magnetic-field generator that includes a magnetic-field generating coil for generating a magnetic field with respect to a detection space of the detected object; detection coils that detect an induced magnetic field generated from the internal coil caused by the magnetic field; a magnetic-field-generating-coil switching unit that selects a magnetic-field generating coil from the magnetic-field generating coils in the magnetic-field generator; a storage unit that stores predetermined information for selecting a magnetic-field generating coil from the magnetic-field generating coils in the magnetic-field generator; and a control unit that controls the magnetic-field-generating-coil switching unit to select the magnetic-field generating coil to be operated among the magnetic-field generating coils in the first magnetic-field generator, based on at least one of a position and a direction of the detected object and based on the predetermined information.

Claims

1. A position detecting device comprising:

a detected object that includes a circuit with at least one internal coil;

a first magnetic-field generator that includes at least one magnetic-field generating coil for generating a first magnetic field with respect to a detection space of the detected object;

a plurality of detection coils that detect an induced magnetic field generated from the internal coil caused by the first magnetic field;

a magnetic-field-generating-coil switching unit that selects at least one magnetic-field generating coil to be operated from the magnetic-field generating coils in the first magnetic-field generator;

a storage unit that stores predetermined information for selecting at least one magnetic-field generating coil to be operated from the magnetic-field generating coils in the first magnetic-field generator; and

a control unit that controls the magnetic-field-generating-coil switching unit to select the at least one magnetic-field generating coil to be operated among the magnetic-field generating coils in the first magnetic-field generator, based on at least one of a position and a direction of the detected object and based on the predetermined information.

2. The position detecting device according to claim 1, wherein the control unit hysteretically selects the magnetic-field generating coil based on the predetermined information.

3. The position detecting device according to claim 1, wherein the predetermined information is a continuous operation time of the selected magnetic-field generating coil.

4. The position detecting device according to claim 1, wherein the predetermined information is a selection sequence of the magnetic-field generating coil.

5. The position detecting device according to claim 1, wherein the predetermined information is information of the first magnetic field generated by the magnetic-field generating coils.

6. The position detecting device according to claim 1, further comprising at least one signal generator that outputs an alternating-current signal to the at least one magnetic-field generating coil, wherein

at a time of selecting the magnetic-field generating coil, the control unit stops an output of the signal generator in an active state, and after a predetermined time has passed, disconnects between the magnetic-field generating coil which is in an active state and the magnetic-field-generating-coil switching unit, then after a predetermined time has passed, connects the selected magnetic-field generating coil with the magnetic-field-generating-coil switching unit, and then after a predetermined time has passed, starts an output of the selected signal generator.

7. The position detecting device according to claim 1, further comprising at least one signal generator that outputs an alternating-current signal to the at least one magnetic-field generating coil, wherein

at a time of selecting the magnetic-field generating coil, the control unit connects the selected magnetic-field generating coil with the magnetic-field-generating-coil switching unit, and after a predetermined time has passed, starts an output of the selected signal generator, then after a predetermined time has passed, stops an output of the signal generator, which has been in an active state, and then after a predetermined time has passed, disconnects between the magnetic-field generating coil, which has been in an active state, and the magnetic-field-generating-coil switching unit.

8. The position detecting device according to claim 1, further comprising a position and direction calculator that calculates a position and a direction of the detected object based on detection results of the detection coils, wherein

the control unit stops calculation of a position and direction by the position and direction calculator during a period where the magnetic-field-generating-coil switching unit is selecting a magnetic-field generating coil.

9. The position detecting device according to claim 1, wherein the control unit selects a plurality of detection coils to be operated from the detection coils according to the selected magnetic-field generating coil.

10. A medical device guidance system comprising:

a medical device that includes a circuit with at least one internal coil and a magnet, the medical device being a detected object;

the position detecting device according to claim 1; and

a second magnetic-field generator that generates a second magnetic field for guiding the medical device by operating the magnet.

11. A position detecting method comprising:

generating a first magnetic field with respect to a detection space of a detected object that includes a circuit with at least one internal coil;

detecting, by a plurality of detection coils, an induced magnetic field generated from the internal coil caused by the first magnetic field;

calculating at least one of a position and a direction of the detected object based on a detection result of the induced magnetic field;

selecting at least one magnetic-field generating coil for generating the first magnetic field, based on at least one of a position and a direction of the detected object and based on predetermined information for selecting at least one magnetic-field generating coil to be operated; and

controlling a magnetic-field-generating-coil switching unit to switch to the selected magnetic-field generating coil.

12. The position detecting method according to claim 11, wherein the selecting includes hysteretically selecting the magnetic-field generating coil based on the predetermined information.

13. The position detecting method according to claim 11, further comprising selecting at least one signal generator that outputs an alternating-current signal to the at least one magnetic-field generating coil, wherein

the controlling includes:

stopping an output of the signal generator in an active state that outputs an alternating-current signal to the magnetic-field generating coil in an active state;

disconnecting, after a predetermined time has passed, between the magnetic-field generating coil which is in an active state and the magnetic-field-generating-coil switching unit;

then connecting, after a predetermined time has passed, the magnetic-field generating coil selected at the magnetic-field generating-coil selecting step with the magnetic-field-generating-coil switching unit; and

then causing, after a predetermined time has passed, the selected signal generator to start an output of an alternating-current signal.

14. The position detecting method according to claim 11, further comprising selecting at least one signal generator that outputs an alternating-current signal to the at least one magnetic-field generating coil, wherein

the controlling includes:

connecting the selected magnetic-field generating coil with the magnetic-field-generating-coil switching unit;

starting, after a predetermined time has passed, an output of the selected signal generator;

then stopping, after a predetermined time has passed, an output of the signal generator which is in an active state; and

then disconnecting, after a predetermined time has passed, between the magnetic-field generating coil which is in an active state and the magnetic-field-generating-coil switching unit.

15. The position detecting method according to claim 11, further comprising selecting a plurality of detection coils to be prepared from the detection coils according to the selected magnetic-field generating coil.