Guidance of invasive medical procedures using implantable tags

• US 20030018246A1
• Filed: 06/17/2002
• Published: 01/23/2003
• Est. Priority Date: 03/11/1999
• Status: Active Grant

• Current Assignee: Biosense, Inc. (Cardinal Health, Inc.)
• Original Assignee: Biosense, Inc. (Cardinal Health, Inc.)
• Inventors: Govari, Assaf, Schwartz, Yitzhack
• Granted Patent: US 7,558,616 B2
• Time in Patent Office: Days
• US Class Current: 600/407
• CPC Class Codes: A61B 10/0041 Detection of breast cancer mammography by transillumination A61B5/0091, by X-rays A61B6/502, by ultrasonic means A61B8/0825
• CPC Class Codes: A61B 10/0233 Pointed or sharp biopsy instruments
• CPC Class Codes: A61B 17/1114 of the digestive tract, e.g. bowels or oesophagus
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 2010/045 Needles pointed biopsy devices with vacuum aspiration A61B10/0283
• CPC Class Codes: A61B 2017/008 Removal of tumors
• CPC Class Codes: A61B 2017/3413 guided by ultrasound
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2063 Acoustic tracking systems, e.g. using ultrasound
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 2090/3908 Soft tissue, e.g. breast tissue
• CPC Class Codes: A61B 2090/3925 ultrasonic
• CPC Class Codes: A61B 2090/3929 Active markers
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 2090/3958 emitting a signal
• CPC Class Codes: A61B 2090/397 electromagnetic other than visible, e.g. microwave
• 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 34/25 User interfaces for surgical systems
• 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 5/061 : Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/062 : using magnetic field
• CPC Class Codes: A61B 90/36 : Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/39 : Markers, e.g. radio-opaque or breast lesions markers

Abstract

Apparatus for locating a tissue within a body of a subject includes an acoustic tag configured to be fixed to the tissue and adapted, responsive to acoustic waves incident thereon, to return acoustic echoes. Acoustic transducers are placed at respective positions so as to direct the acoustic waves into the body toward the tissue and to receive the acoustic echoes returned from the tag responsive to the acoustic waves, generating first signals responsive to the received echoes. Transducer position sensors are coupled respectively to the acoustic transducers so as to generate second signals indicative of the respective positions of the acoustic transducers in an external frame of reference. A processing unit processes the first signals and the second signals so as to determine coordinates of the acoustic tag in the external frame of reference.

Claims

1. Apparatus for locating a tissue within a body of a subject, comprising:

an acoustic tag configured to be fixed to the tissue and adapted, responsive to acoustic waves incident thereon, to return acoustic echoes;

a plurality of acoustic transducers, which are adapted to be placed at respective positions so as to direct the acoustic waves into the body toward the tissue and to receive the acoustic echoes returned from the tag responsive to the acoustic waves, the transducers being further adapted to generate first signals responsive to the received echoes;

a plurality of transducer position sensors, coupled respectively to the acoustic transducers so as to generate second signals indicative of the respective positions of the acoustic transducers in an external frame of reference; and

a processing unit, coupled to process the first signals and the second signals so as to determine coordinates of the acoustic tag in the external frame of reference.

2. Apparatus according to claim 1, wherein there is substantially no wired connection to the tag.

3. Apparatus according to claim 1, wherein the acoustic waves incident on the tag have a first frequency, and wherein the acoustic echoes returned by the tag have a second frequency, different from the first frequency.

4. Apparatus according to claim 3, wherein the tag comprises a shell defining a cavity therein and a medium contained within the shell, and wherein the shell and the medium are selected and constructed to resonate at the second frequency.

5. Apparatus according to claim 1, wherein the first signals are indicative of respective distances between the acoustic transducers and the tag, and wherein the processing unit is adapted to determine a location of the tag relative to the acoustic transducers by triangulating the distances.

6. Apparatus according to claim 1, and comprising one or more field generators, which are fixed in the external frame of reference and which are adapted to generate electromagnetic fields in a vicinity of the acoustic transducers, and wherein the transducer position sensors comprise field sensors, in which electrical currents flow responsive to the electromagnetic fields, and wherein the second signals correspond to the electrical currents flowing in the field sensors.

7. Apparatus according to claim 6, and comprising a tool position sensor, which is configured to be fixed to a medical device that is to be applied to the body and which is adapted to generate a third signal responsive to the electromagnetic fields, wherein the processing unit is further coupled to process the third signal so as to determine the coordinates of the medical device relative to the acoustic tag.

8. Apparatus according to claim 7, and comprising a display, which is adapted to present a visual indication of the coordinates of the medical device relative to the acoustic tag for use by an operator of the medical device, wherein the display and field generator coils are contained together with the processing unit in an integral package.

9. Apparatus according to claim 1, wherein the transducer position sensors comprise field generators, which are adapted to generate electromagnetic fields, and comprising one or more field receivers, which are fixed in the external frame of reference, such that electrical currents flow in the field receiver coils corresponding to the second signals responsive to the electromagnetic fields.

10. Apparatus according to claim 1, and comprising a tool position sensor, which is configured to be fixed to a medical device that is to be applied to the body and which is adapted to generate a third signal indicative of the coordinates of the medical device in the external frame of reference, wherein the processing unit is further coupled to process the third signal so as to determine the coordinates of the medical device relative to the acoustic tag.

11. Apparatus according to claim 10, wherein the medical device comprises an invasive tool, which is adapted to penetrate into the body so as to reach the tissue, and comprising a display, which is adapted to present a visual indication for use by an operator of the invasive tool of an orientation of the tool relative to an axis passing through the acoustic tag.

12. Apparatus according to claim 11, wherein the invasive tool comprises a handle, and wherein the display is mounted on the handle.

13. Apparatus according to claim 11, wherein the invasive tool is adapted to perform a surgical procedure on the tissue.

14. Apparatus according to claim 11, wherein the invasive tool comprises an endoscope.

16. A method according to claim 15, wherein there is substantially no wired connection to the acoustic tag.

17. A method according to claim 15, wherein actuating the acoustic transducers comprises directing the acoustic waves into the body at a first frequency, and wherein receiving the acoustic echoes comprises receiving the echoes returned by the tag at a second frequency, different from the first frequency.

18. A method according to claim 17, wherein the tag comprises a shell defining a cavity therein and a medium contained within the shell, and wherein the shell and the medium are selected and constructed to resonate at the second frequency.

19. A method according to claim 15, wherein receiving the acoustic echoes comprises generating the first signals so as to indicate respective distances between the acoustic transducers and the tag, and wherein processing the first signals comprises determining a location of the tag relative to the acoustic transducers by triangulating the distances.

20. A method according to claim 15, wherein generating the second signals comprises generating electromagnetic fields in a vicinity of the acoustic transducers, and sensing electrical currents flowing responsive to the electromagnetic fields in field sensors that are coupled to the acoustic transducers, wherein the second signals correspond to the electrical currents flowing in the field sensors.

21. A method according to claim 20, and comprising:

fixing a tool position sensor to a medical device that is to be applied to the body;

generating a third signal responsive to the electromagnetic fields using the tool position sensor; and

processing the third signal so as to determine the coordinates of the medical device relative to the acoustic tag.

22. A method according to claim 15, wherein generating the second signals comprises generating electromagnetic fields using field generators coupled to the acoustic transducers, and sensing electrical currents flowing responsive to the electromagnetic fields using field receivers fixed in the external frame of reference, wherein the second signals correspond to the electrical currents flowing in the field receivers.

23. A method according to claim 15, and comprising:

fixing a tool position sensor to a medical device that is to be applied to the body;

generating a third signal using the tool position sensor indicative of the coordinates of the medical device in the external frame of reference; and

processing the third signal so as to determine the coordinates of the medical device relative to the acoustic tag.

24. A method according to claim 23, wherein the medical device comprises an invasive tool, which is adapted to penetrate into the body so as to reach the tissue, and comprising displaying a visual indication for use by an operator of the invasive tool of an orientation of the tool relative to an axis passing through the acoustic tag.

25. A method according to claim 24, wherein the invasive tool comprises a handle, and wherein the displaying the visual indication comprises displaying the indication on the handle.

26. A method according to claim 24, and comprising performing a surgical procedure on the tissue using the invasive tool.

27. A method according to claim 24, and comprising performing an endoscopic procedure on the tissue using the invasive tool.

15. A method for locating a tissue within a body of a subject, comprising:

fixing an acoustic tag to the tissue;

placing a plurality of acoustic transducers at respective positions in proximity to the body;

actuating the acoustic transducers so as to direct acoustic waves into the body toward the tissue;

receiving acoustic echoes returned from the tag responsive to the acoustic waves, and generating first signals responsive to the received echoes;

generating second signals indicative of the respective positions of the acoustic transducers in an external frame of reference using a plurality of transducer position sensors, coupled respectively to the acoustic transducers; and

processing the first signals and the second signals so as to determine coordinates of the acoustic tag in the external frame of reference.