Device and method for determining the location of a vascular opening prior to application of HIFU energy to seal the opening

• US 20070149880A1
• Filed: 12/22/2005
• Published: 06/28/2007
• Est. Priority Date: 12/22/2005
• Status: Abandoned Application

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Willis, N.
• Application Number:
  US11/316,059
• Publication Number:
  US 20070149880A1
• Time in Patent Office: Days
• US Class Current: 600/471
• CPC Class Codes: A61B 17/0057 Implements for plugging an opening in the wall of a hollow or tubular organ, e.g. for sealing a vessel puncture or closing a cardiac septal defect sutures A61B17/04; closing rectum or urethra near body surface A61F2/0009
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2090/3786 receiver only
• CPC Class Codes: A61B 2090/3788 transmitter only
• 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 8/0833 involving detecting or locating foreign bodies or organic structures
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: A61B 8/42 Details of probe positioning or probe attachment to the patient
• CPC Class Codes: A61N 2007/0078 with multiple treatment transducers
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

System and methods for locating a vascular opening and thereafter therapeutically sealing the wound with high intensity focused ultrasound (HIFU) are disclosed. The improved system utilizes three or more reference transducers mounted on the HIFU applicator and another transducer mounted on a distal end of a probe. The probe is used with the imaging array of the HIFU applicator. The operator places the distal end of the probe at the vessel opening using the imaging array. The position of the applicator may need to be adjusted on the patient'"'"'s body, depending upon the feedback of the imaging array data. The transducers transmit and receive acoustic energy and generate signals indicative of their location. Time-of-flight (TOF) calculations are performed to determine the distances between the probe transducer and the reference transducers. A three-dimensional position of the end of the probe is calculated using a multi-dimensional scaling (MDS) algorithm. The coordinates are then converted to a local coordinate system using a Procrustean similarity transform (PSD), the output of which is used to generate the focal point of the HIFU therapeutic array.

Claims

1. A medical system comprising:

a probe comprising a distal end;

at least one probe transducer mounted on the distal end of the probe;

a high intensity focused ultrasound (HIFU) device comprising a therapeutic array, and control circuitry, the HIFU device further comprising at least three applicator transducers mounted around the therapeutic array;

one of the probe and applicator transducers generating acoustic energy and the other of the probe and reference transducers receiving said acoustic energy and generating electrical signals in response thereto;

the control circuitry performing time-of-flight (TOF) calculations based on the electrical signals that indicate distances between the probe transducer and individual applicator transducers, the control circuitry performing calculations generating three-dimensional position data of the probe transducer with respect to the applicator transducers and the therapeutic array based on the TOF calculations, and the control circuitry performing local coordinate calculations for the probe transducer with respect to the therapeutic array based on the three-dimensional position data.

2. The medical system of claim 1 wherein the control circuitry calculates the three-dimensional position data with a multi-dimensional scaling (MDS) algorithm.

3. The medical system of claim 2 wherein the control circuitry performs the local coordinate calculations using a Procrustean similarity transform (PST).

4. The system of claim 1, wherein the at least three applicator transducers comprise four transducers.

5. The system of claim 4 wherein three-dimensional position data calculations performed by the control circuitry are performed a plurality of times for different sets of three of the four applicator transducers.

6. The system of claim 5 wherein the results of the three-dimensional position data calculations are averaged.

7. The system of claim 1 further comprising a pressure transducer diposed at the probe tip.

8. The system of claim 1 wherein probe transducer is a combination acoustic and pressure transducer.

9. The system of claim 1 wherein the controller calculates a focal depth for HIFU therapy based on the local coordinate calculation.

10. The system of claim 1 wherein the controller generates an alarm if the therapeutic array is displaced laterally or longitudinally from the distal end of the probe by a distance greater than a predetermined threshold distance.

11. A high intensity focuses ultrasound (HIFU) therapy system, comprising:

a probe comprising a distal end;

at least one acoustic transducer mounted on the distal end of the probe;

an applicator comprising a therapeutic array and an imaging array, the applicator being linked to a controller, the applicator further comprising at least three reference transducers mounted around the therapeutic array;

the probe transducer transmitting acoustic energy to the reference transducers, the reference transducers generating electrical signals as a result of the acoustic energy received from the probe transducer;

the imaging array generating and transmitting signals indicative of locations of the probe and surrounding tissue structures;

control circuitry performing time-of-flight (TOF) calculations based on the electrical signals that indicate distances between the probe transducer and individual reference transducers, the control circuitry generating three-dimensional position data of the probe transducer with respect to the reference transducers and the therapeutic array based on the TOF calculations, and the control circuitry generating local coordinate information of the probe transducer with respect to the therapeutic array.

12. The HIFU system of claim 11 wherein the control circuitry generates the three-dimensional position data with a multi-dimensional scaling (MDS) algorithm.

13. The HIFU system of claim 12 wherein the control circuitry generates the local coordinate information using a Procrustean similarity transform (PST).

14. The HIFU system of claim 11 further comprising a pressure transducer diposed at the probe tip.

15. The HIFU system of claim 11 wherein probe transducer is a combination acoustic and pressure transducer.

16. A method for sealing an opening or puncture in a vessel, the method comprising:

inserting a probe through a skin puncture site and moving a distal end of the probe towards the vessel opening, the distal end of the probe being connected to at least one probe transducer, the at least one probe transducer generating acoustic energy directed towards an applicator comprising an imaging array, a therapeutic array and at least three reference transducers mounted around the therapeutic array, the at least one probe transducer measuring pressure at the probe tip;

generating signals from the imaging array indicative of locations of the probe and surrounding tissue;

generating pressure signals indicating pressure at the distal end of the probe;

manipulating the probe until a pressure change is indicated at the distal end of the probe;

transmitting acoustic energy from the probe transducer towards the at least three reference transducers and receiving acoustic energy from the probe transducer at the reference transducers;

generating electrical signals based on the received acoustic energy;

performing time-of-flight (TOF) calculations based on the electrical signals;

calculating a three dimensional position of the distal end of the probe with respect to the imaging and therapeutic arrays based on the TOF calculations;

calculating local coordinates of the distal end of the probe relative to the imaging and therapeutic arrays based on the three-dimensional data position.

17. The method of claim 16 wherein the calculating of the three-dimensional position data comprises using a multi-dimensional scaling (MDS) algorithm.

18. The method of claim 16 wherein the calculating of the local coordinates of the probe transducer comprises using a Procrustean similarity transform (PST).

19. A method for sealing an opening or puncture in a vessel, the method comprising:

inserting a probe through a skin puncture site and moving a distal end of the probe towards the vessel opening, the distal end of the probe being connected to at least one probe transducer, the probe transducer generating acoustic energy directed towards an applicator comprising an imaging array, a therapeutic array and at least three reference transducers mounted around the therapeutic array;

generating signals from the imaging array indicative of locations of the probe and surrounding tissue;

generating video images of the distal end of the probe and surrounding tissue based on the signals from the imaging array;

manipulating the probe to place the distal end of the probe at or near the opening in the vessel while viewing the video images;

transmitting acoustic energy from the probe transducer towards the at least three reference transducers and receiving acoustic energy from the probe transducer at the reference transducers;

generating electrical signals based on the received acoustic energy;

performing time-of-flight (TOF) calculations based on the electrical signals;

calculating a three dimensional position of the distal end of the probe with respect to the imaging and therapeutic arrays based on the TOF calculations;

calculating local coordinates of the distal end of the probe relative to the imaging and therapeutic arrays based on the three-dimensional data position.

20. The method of claim 19 wherein the calculating of the three-dimensional position data comprises using a multi-dimensional scaling (MDS) algorithm.

21. The method of claim 19 wherein the calculating of the local coordinates of the probe transducer comprises using a Procrustean similarity transform (PST).

22. The method of claim 19, further comprising confirming the probe tip is located at the vessel opening by measuring a pressure change as the probe tip enters the vessel opening.

23. A method for the location of a vessel opening or puncture, the method comprising:

a) inserting a probe through a skin puncture site and moving a distal end of the probe towards the vessel opening, the distal end of the probe being connected to at least one probe transducer;

b) receiving the acoustic energy from the probe transducer at three or more applicator transducers mounted around a therapeutic array of a high intensity focused ultrasound (HIFU) applicator;

c) generating acoustic energy from the probe transducer;

d) generating electrical signals based on the received acoustic energy;

e) generating pressure data at the distal end of the probe;

f) performing time-of-flight (TOF) calculations based on the electrical signals that indicate relative locations of the three or more applicator transducers with respect to the probe transducer;

g) calculating three-dimensional position data of the probe transducer with respect to the applicator transducers and the therapeutic array based on the TOF calculations;

h) calculating local coordinate information of the probe transducer with respect to the therapeutic array based on the three-dimensional position data;

i) manipulating the probe to place the distal end of the probe at or near the opening based on changes in the pressure data;

j) manipulating the HIFU applicator until the therapeutic array is laterally and longitudinally aligned with the opening in the vessel;

k) repeating parts (c) through (h) each time parts (i) and (j) are carried out resulting in repositioning of the probe or applicator;

l) calculating a focal depth for the therapeutic array based on the local coordinates.

24. A method for the location of a vessel opening or puncture, the method comprising:

a) inserting a probe through a skin puncture site and moving a distal end of the probe towards the vessel opening, the distal end of the probe being connected to at least one probe transducer;

b) receiving the acoustic energy from the probe transducer at three or more applicator transducers mounted around a therapeutic array of a high intensity focused ultrasound (HIFU) applicator, the HIFU applicator comprising an imaging array;

c) generating acoustic energy from the probe transducer;

d) generating electrical signals based on the received acoustic energy;

e) generating video images of the distal end of the probe and surrounding tissue based on the signals from the imaging array;

f) performing time-of-flight (TOF) calculations based on the electrical signals that indicate relative locations of the three or more applicator transducers with respect to the probe transducer;

g) calculating three-dimensional position data of the probe transducer with respect to the applicator transducers and the therapeutic array based on the TOF calculations;

h) calculating local coordinate information of the probe transducer with respect to the therapeutic array based on the three-dimensional position data;

i) manipulating the probe to place the distal end of the probe at or near the opening in the vessel while viewing the video images;

j) manipulating the HIFU applicator until the therapeutic array is laterally and longitudinally aligned with the opening in the vessel;

k) repeating parts (c) through (h) each time parts (i) and (j) are carried out resulting in repositioning of the probe or applicator;

l) calculating a focal depth for the therapeutic array based on the local coordinates.