Image plane sensing methods and systems for intra-patient probes

• US 20060074319A1
• Filed: 09/27/2004
• Published: 04/06/2006
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Bolorforosh, Mirsaid, Barnes, Stephen R., Thigpen, Tim, Marian, Vaughn R., Bruce, David I.
• Granted Patent: US 7,618,374 B2
• Time in Patent Office: Days
• US Class Current: 600/466
• 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 8/0833 involving detecting or locating foreign bodies or organic structures

Abstract

A position of an imaging plane relative to a catheter or other probe is aligned with tissue of interest. Ultrasound tissue images may be registered to the catheter position with minimal rotational ambiguity. The spatial position of an ablation catheter or other device with respect to the imaging plane is more accurately determined, allowing a physician to identify specific anatomy in the relative location of a catheter or catheters. Another alternative or additional approach to determining the position of an imaging plane is to determine the relative position of two or more catheters. A catheter associated with imaging is then moved or bent in a direction having a known spatial relationship with the imaging plane. The position of the catheter is relative to each is then determined again to determine the angle or position of the imaging plane. In addition or as an alternative to determining an angular position of an imaging plane relative to a catheter, an ultrasound image of tissue is generated with acoustic elements for position identification. The acoustic elements are used as an imaging transducer array as well as devices for determining relative positions of the catheters.

Claims

1. A system for determining a position of an imaging plane relative to a catheter, the system comprising:

a first catheter having an ultrasound imaging transducer array, the ultrasound imaging transducer array corresponding to the imaging plane;

a second catheter having a first antenna, the second catheter at least in part different than the first catheter; and

a processor operable to determine angular position information of the imaging plane relative to one of the first catheter, the second catheter and combinations thereof as a function of a first signal of the first antenna.

2. The system of claim 1 wherein the first catheter comprises a second antenna positioned relative to the ultrasound imaging transducer array, and wherein the processor is operable to determine the angular position information of the imaging plane as a function of a second signal of the second antenna.

3. The system of claim 2 wherein the first signal is a transmit signal and the second signal is a receive signal responsive to the first signal.

4. The system of claim 2 wherein the second antenna has a variable thickness as a function of angle around the first catheter.

5. The system of claim 4 wherein the first catheter further comprises a third antenna having a variable thickness as a function of angle around the first catheter, the third and second antennas curving as a function of length in a same plane substantially perpendicular to a longitudinal axis of the first catheter.

6. The system of claim 2 wherein the second antenna comprises a radio frequency identification device, the first catheter further comprising at least two additional radio frequency identification devices, wherein the processor is operable to determine the angular position information of the imaging plane relative to the first catheter as a function of the second signal and signals from the additional radio frequency identification devices.

7. The system of claim 1 wherein the processor is operable to determine a position of the imaging plane relative to the second catheter.

8. The system of claim 2 further comprising at least third and fourth antennas on the first catheter, the second, third and fourth antennas being acoustic elements separate from the ultrasound imaging transducer array, wherein the processor is operable to determine angular position information of the imaging plane relative to the first catheter as a function of signals of the second, third and fourth antennas.

9. The system of claim 2 wherein the second antenna is a separate device integrated on a same substrate as the ultrasound imaging transducer array.

10. The system of claim 2 wherein the processor is responsive to the first and second signals and at least one signal from the ultrasound imaging transducer array to determine the angular position information.

11. The system of claim 2 wherein the processor is operable to determine the angular position information as a function of different positions of the first catheter and the second antenna on the first catheter.

38. The system of claim 6 wherein the processor is operable to determine the angular position information as a function of signal strength of the second signal and the signals from the additional radio frequency identification devices.

12. A method for determining a position of an imaging plane within a patient, the method comprising:

(a) transmitting from a first intra-patient probe;

(b) receiving a signal at a second intra-patient probe in response to the transmission of (a);

(c) determining an angular position of the imaging plane of a transducer array of one of the first and second intra-patient probes as a function of the signal.

13. The method of claim 12 wherein (a) comprises transmitting a wideband pulse, wherein (b) comprises receiving the signal with an antenna having a variable thickness, and wherein (c) comprises determining the angular position of the imaging plane as a function of a frequency content of the signal.

14. The method of claim 12 wherein (a) comprises transmitting from first and second antennas each having a variable thickness and different phases, wherein (b) comprises receiving signals in response to both the first and second antennas, and wherein (c) comprises determining the angular position of the imaging plane as a function of a frequency content and the relative phase of the signals.

15. The method of claim 12 wherein (a) comprises transmitting an interrogation signal, wherein (b) comprises transponding from a plurality of radio frequency identification devices on the second intra-patient probe, and wherein (c) comprises determining the angular position of the imaging plane relative to the second intra-patient probe as a function of relative transponding signal strengths of (b).

16. The method of claim 12 wherein (c) comprises determining the angular position of the imaging plane relative to the first intra-patient probe, the first intra-patient probe having the transducer array.

17. The method of claim 12 wherein (c) comprises determining the angular position of the imaging plane relative to the second intra-patient probe, the second intra-patient probe having the transducer array.

18. The method of claim 12 wherein (a) comprises transmitting an ultrasound signal, wherein (b) comprises receiving the ultrasound signal, one of (a) and (b) being performed with an array of transducer elements different than and at a known spatial orientation relative to the transducer array, and wherein (c) comprises determining the angular position of the imaging plane as a function of the ultrasound signal.

19. The method of claim 12 further comprising:

(d) receiving a further signal from the transducer array different than the signal of (b);

wherein (c) comprises determining the angular position as a function of the signal and the further signal.

20. The method of claim 12 further comprising:

(d) repeating (a) and (b) with a tip of the one of the first and second intra-patient probes having the transducer array bent in a different position than for the initial performance of (a) and (b)

wherein (c) comprises determining the angular position as a function of the different position of the tip.

21. A method for using position information for imaging, the method comprising:

(a) determining a relative position of at least first and second catheters with first and second groups of acoustic elements, the first group of acoustic elements on the first catheter and second group of acoustic elements on the second catheter;

(b) generating an ultrasound image of tissue with the first and second groups of acoustic elements as a function of the relative position.

22. The method of claim 21 wherein the first group of acoustic elements are spaced apart along the first catheter and the second group of acoustic elements are spaced apart along the second catheter, wherein (a) comprises:

(a1) transmitting from at least one acoustic element of the first group;

(a2) receiving with acoustic elements of the second group in response to (a1);

(a3) transmitting from at least one acoustic element of the second group;

(a4) receiving with acoustic elements of the first group in response to (a3);

(a5) determining positions of the acoustic elements of the first and second groups as a function of the transmissions and receptions of (a1)-(a4); and

wherein (b) comprises generating the ultrasound image with the acoustic elements of the first and second groups as the transducer array by beamformation based on the positions of the acoustic elements.

23. The method of claim 21 wherein (b) comprises generating a three-dimensional representation as the ultrasound image, the three-dimensional representation including at least one of the first and second catheters.

24. A method for determining a position of an imaging plane relative to a catheter, the method comprising:

(a) determining a relative position of at least first and second catheters with first and second groups of acoustic elements, the first group of acoustic elements on the first catheter and second group of acoustic elements on the second catheter, the first catheter comprising an acoustic imaging transducer array;

(b) bending the first catheter after (a);

(c) repeating (a) after (b); and

(d) determining the position of the imaging plane as a function of the relative positions determined in (a) and (c).

25. The method of claim 24 wherein the first group of acoustic elements are spaced apart along the first catheter and the second group of acoustic elements are spaced apart along the second catheter, wherein (a) comprises:

(a1) transmitting from at least one acoustic element of the first group;

(a2) receiving with acoustic elements of the second group in response to (a1);

(a3) transmitting from at least one acoustic element of the second group;

(a4) receiving with acoustic elements of the first group in response to (a3);

(a5) determining positions of the acoustic elements of the first and second groups as a function of the transmissions and receptions of (a1)-(a4);

wherein (b) comprises bending a tip in a known direction relative to the imaging plane, the imaging plane spaced from the tip; and

wherein (d) comprises determining the position as a function of the known direction and the difference in relative positions determined in (a) and (c).

26. A system for determining a position of an imaging plane relative to a catheter, the system comprising:

a first catheter having an ultrasound imaging transducer array, the ultrasound imaging transducer array corresponding to the imaging plane;

a first antenna spaced from the first catheter; and

a processor operable to determine angular position information of the imaging plane relative to one of the first catheter or the antenna as a function of a first signal of the first antenna.

27. The system of claim 26 wherein the first antenna comprises a plurality of ultrasound elements.

28. The system of claim 26 wherein the first antenna is positioned outside of a patient.

29. The system of claim 28 wherein the first antenna comprises a plurality of ultrasound elements positioned on the skin of the patient.

30. The system of claim 28 wherein the processor is operable to determine an azimuthal position of the ultrasound imaging transducer array as a function of distance from the first antenna.

31. The system of claim 28 wherein the processor is operable to determine an elevation position of the ultrasound imaging transducer array as a function of signal strength of the first signal.

32. The system of claim 28 wherein the processor is operable to determine relative positions of a sequence of imaging planes for three-dimensional reconstruction.

33. The system of claim 26 wherein the first antenna is one an intra-patient probe.

34. A method for determining a position of an imaging plane within a patient, the method comprising:

(a) transmitting from one of an ultrasound imaging transducer array of a first intra-patient probe and an antenna;

(b) receiving a signal with the other of the ultrasound imaging transducer array and the antenna in response to the transmission of (a);

(c) determining an angular position of the imaging plane of the ultrasound imaging transducer array as a function of the signal.

35. The method of claim 34 wherein the antenna is on an outside of the patient.

36. The method of claim 35 wherein (c) comprises determining a position of the ultrasound imaging transducer array in response to time of flight information of the signal and determining an angle of the imaging plane relative to the position as a function of signal strength of the signal.

37. The method of claim 34 wherein the antenna is on another intra-patient probe.