Ultrasound Imaging Catheter With Pivoting Head

• US 20090264759A1
• Filed: 04/22/2008
• Published: 10/22/2009
• Est. Priority Date: 04/22/2008
• Status: Active Grant

• Current Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Original Assignee: Ep Medsystems Incorporated (Abbott Laboratories)
• Inventors: Byrd, Charles Bryan
• Granted Patent: US 8,052,607 B2
• Time in Patent Office: Days
• US Class Current: 600/445
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/4466 involving deflection of the probe
• CPC Class Codes: A61B 8/4488 the transducer being a phased array
• CPC Class Codes: A61M 25/0136 Handles therefor

Abstract

An ultrasound imaging catheter system includes a pivot head assembly coupled between a ultrasound transducer array and the distal end of the catheter. The pivot head assembly includes a pivot joint enabling the transducer array to pivot through a large angle about the catheter centerline in response pivot cables controlled by a wheel within a handle assembly. Pivoting the ultrasound transducer array approximately 90° once the catheter is positioned by rotating the catheter shaft and bending the distal section of the catheter, clinicians may obtain orthogonal 2-D ultrasound images of anatomical structures of interest in 3-D space. Combining bending of the catheter by steering controls with pivoting of the transducer head enables a greater range of viewing perspectives. The pivot head assembly enables the transducer array to pan through a large angle to image of a larger volume than possible with conventional ultrasound imaging catheter systems.

Claims

1. An ultrasound imaging system, comprising:

a catheter having a proximal end and a distal end;

a pivot assembly coupled to a distal end of the catheter; and

an ultrasound imaging transducer assembly coupled to the pivot assembly.

2. The ultrasound imaging system as in claim 1, wherein the pivot assembly comprises:

a proximal support structure coupled to the catheter;

a distal support structure coupled to the ultrasound imaging transducer; and

a pintle having a long axis, wherein the proximal and distal support structures are rotatably coupled by the pintle to form a hinge joint.

3. The ultrasound imaging system of claim 2, further comprising:

a first pivot control cable coupled to the distal support structure and threaded through the catheter to the proximal end of the catheter; and

a second pivot control cable coupled to the distal support structure and threaded through the catheter to the proximal end of the catheter.

4. The ultrasound imaging system of claim 3, further comprising a handle assembly coupled to the proximal end of the catheter, the handle assembly comprising a pivot control actuator coupled to the first and second pivot control cables and configure so that movement of the pivot control actuator tensions one of the first and second pivot control cables sufficient to cause the pivot assembly to pivot about the hinge joint.

5. The ultrasound imaging system of claim 4, wherein the pivot control actuator comprises:

a pivot wheel support structure;

an axel positioned within the pivot wheel support structure;

a pivot wheel rotatably coupled to the pivot wheel support structure via the axel; and

a spool coupled to the pivot wheel and to the a first and second pivot control cables, wherein the first and second pivot control cables are coupled to the spool so that rotation of the pivot wheel in a first direction causes the first pivot control cable to be tensioned while the second pivot control cable is loosened and rotation of the pivot wheel in a second direction opposite the first direction causes the second pivot control cable to be tensioned while the first pivot control cable is loosened.

6. The ultrasound imaging system of claim 4, further comprising:

a bendable portion subassembly coupled between the pivot assembly and the distal end of the catheter;

first and second steering cables coupled to the bendable portion subassembly; and

a steering control actuator coupled to the handle assembly and the first and second steering cables,

wherein the steering control actuator, first and second steering cables and bendable portion subassembly are configured so that actuation of the steering control actuator in a first actuator direction causes the bendable portion subassembly to bend in a first bending direction and actuation of the steering control actuator in a second actuator direction opposite the first actuator direction causes the bendable portion subassembly to bend in a second bending direction.

7. The ultrasound imaging system of claim 6, wherein the ultrasound imaging transducer assembly is oriented with respect to the catheter so that an imaging plane of the is orthogonal to a plane defined by a bend in the bendable portion.

8. The ultrasound imaging system of claim 2, wherein the ultrasound imaging transducer assembly is oriented with respect to the hinge joint so that an imaging plane is parallel to the long axis of the pintle.

9. The ultrasound imaging system of claim 2, wherein the ultrasound imaging transducer assembly is oriented with respect to the hinge joint so that an imaging plane is perpendicular to the long axis of the pintle.

10. The ultrasound imaging system of claim 6, wherein steering control actuator comprises:

a cylinder encircling and rotatably coupled to the handle assembly, the cylinder having threads on an interior surface; and

a slide actuator slidably coupled to the handle assembly and to the first and second steering cables, the slide actuator having partial threads on an outer surface configured to engage the threads on the interior surface of the cylinder, wherein;

the handle assembly includes a slot configure to constrain motion of the slide actuator parallel to a long axis of the handle assembly;

the slide actuator is coupled to the first and second steering cables so that when the slide actuator moves in a proximal direction the first steering cable is tensioned while the second steering cable is loosened and when the slide actuator moves in a distal direction the second steering cable is tensioned while the first steering cable is loosened.

11. The ultrasound imaging system as in claim 1, wherein rotational movement of the pivot assembly has a zero radius of curvature.

12. A method for imaging an internal organ of a patient, comprising:

positioning an ultrasound imaging catheter within the internal organ of the patient, the ultrasound imaging catheter including a pivot assembly coupled to a distal end of the catheter and an ultrasound imaging transducer assembly coupled to the pivot assembly;

obtaining a first ultrasound image from the ultrasound imaging transducer assembly;

pivoting the ultrasound imaging transducer assembly about the pivot assembly without otherwise moving the ultrasound imaging catheter; and

obtaining a second ultrasound image from ultrasound imaging transducer assembly.

13. An ultrasound imaging catheter, comprising:

an ultrasound imaging transducer; and

means for pivoting the ultrasound imaging transducer through an angle in response to user pivot control actuations.

14. The ultrasound imaging catheter of claim 13, wherein the means for pivoting the ultrasound imaging transducer through an angle in response to user pivot control actuations comprises:

first and second pivot control cables;

means for pivoting the ultrasound imaging transducer in response to tension applied to one of the first and second pivot control cables; and

means for tensioning one of the first and second pivot control cables in response to user actuation.

15. The ultrasound imaging catheter of claim 14, further comprising means for bending the catheter in response to user steering control actuations.

16. The ultrasound imaging catheter of claim 15, wherein the means for bending the catheter in response to user steering control actuations comprises:

first and second steering control cables;

means for bending the catheter in response to tension applied to one of the first and second steering control cables; and

means for tensioning one of the first and second steering control cables in response to user actuation.