Ultrasound transducer assembly

• US 6,283,920 B1
• Filed: 09/08/2000
• Issued: 09/04/2001
• Est. Priority Date: 02/01/1993
• Status: Expired due to Term

• Current Assignee: Volcano Corporation (Koninklijke Philips N.V.)
• Original Assignee: Endosonics Corporation (JOMED NV)
• Inventors: Rizzuti, Gary P., Eberle, Michael J., Kiepen, Horst F.
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): Imam, Ali M.
• Application Number:
  US09/658,323
• Time in Patent Office: 361 Days
• Field of Search: 600/459, 600/463, 600/466, 600/467, 600/462, 29/253.5
• US Class Current: 600/459
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• 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 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: A61B 8/4488 the transducer being a phased array
• CPC Class Codes: A61B 8/4494 characterised by the arrangement of the transducer elements devices for short-range imaging using particular transducer elements arrangements under G01S15/8909; arrangements of transducers in generation of mechanical vibrations of infrasonic, sonic or ultrasonic frequency B06B1/0607
• CPC Class Codes: B06B 1/0633 Cylindrical array
• CPC Class Codes: B06B 1/067 which is used as, or combined with, an impedance matching layer
• CPC Class Codes: B06B 1/0674 and a low impedance backing, e.g. air
• CPC Class Codes: B06B 2201/76 Medical, dental
• CPC Class Codes: G01S 15/892 the array being curvilinear
• CPC Class Codes: G01S 15/8979 Combined Doppler and pulse-echo imaging systems
• CPC Class Codes: G01S 15/8981 Discriminating between fixed and moving objects or between objects moving at different speeds, e.g. wall clutter filter
• CPC Class Codes: G01S 15/899 Combination of imaging systems with ancillary equipment
• CPC Class Codes: G10K 11/004 Mounting transducers, e.g. provided with mechanical moving or orienting device mountings specially adapted to a particular sound-producing device, see the preceding groups G10K1/00 - G10K9/00, e.g. G10K1/26, G10K1/28, G10K9/22; arrangements of sonic watch equipment on submarines B63G8/39; buoys B63B22/00
• CPC Class Codes: G10K 11/008 Arrays of transducers seismic streamers, see G01V1/20
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

An ultrasound catheter is disclosed for providing substantially real-time images of small cavities. The ultrasound catheter is characterized by separate and distinct materials for backing the transducers and for carrying the electronics components. The separate materials comprise an electronics carrier meeting the requirements for holding the integrated circuit of the ultrasound device and a backing material displaying superior characteristics relating to reducing ringing and minimizing the effect of other sources of signal degradation in the transducer assembly. Also, in accordance with the present invention, a technique is described for connecting the conductor lines of the separate transducer assembly and electronics body.

Claims

1. A method of making an ultrasound transducer assembly, said method comprising the steps of:

manufacturing a planar sheet comprising a set of ultrasound transducer elements and a substrate;

reshaping the planar sheet into a substantially cylindrical shape; and

bonding the planar sheet to a substantially cylindrical backing material.

2. A method as defined in claim 1, wherein the backing material comprises a material having an acoustic impedance of less than 10 MRayls.

3. A method as defined in claim 1, wherein the backing material comprises epoxy resin.

4. A method as defined in claim 1, wherein the reshaping step causes the substrate to be located at the outside of the set of ultrasound transducer elements.

5. A method as defined in claim 1, further comprising the step of:

electrically coupling at least one integrated circuit to the ultrasound transducer elements.

6. A method as defined in claim 5, wherein the at least one integrated circuit is comprised of an inverted chip design.

7. A method as defined in claim 5, further comprising the step of:

providing an electronics carrier for supporting the at least one integrated circuit, and wherein the backing material has a relatively lower acoustic impedance than that of the electronics carrier.

8. A method of making an imaging catheter, comprising the steps of:

forming a catheter shaft;

attaching an ultrasound transducer assembly to the catheter shaft, the ultrasound transducer assembly formed by the steps of;

manufacturing a planar sheet comprising a set of transducer elements and a substrate;

reshaping the planar sheet into a substantially cylindrical shape; and

bonding the planar sheet to a substantially cylindrical backing material.

9. A method as defined in claim 8, further comprising the step of:

attaching a balloon to the catheter shaft.

10. A method as defined in claim 8, wherein the reshaping step causes the substrate to be located at the outside of the set of transducer elements.

11. A method as defined in claim 10, wherein the substrate comprises a matching layer for the ultrasound transducer assembly.

12. A method as defined in claim 8, further comprising the step of:

providing an electronics carrier for supporting at least one integrated circuit that is electrically coupled to the set of transducer elements, and wherein the backing material has a relatively lower acoustic impedance than that of the electronics carrier.

13. A method as defined in claim 12, wherein the at least one integrated circuit is comprised of an inverted chip design.

14. An ultrasound transducer assembly comprising:

an ultrasound transducer array including a set of ultrasound transducer elements;

a substrate layer comprising a pliable sheet material formed into a substantially cylindrical shape, the substrate layer providing a platform to which the ultrasound transducer elements are fixed; and

the substantially cylindrical shaped substrate layer is bonded to a substantially cylindrical backing material.

15. An ultrasound transducer assembly as defined in claim 14, wherein the backing material comprises a material having an acoustic impedance of less than 10 MRayls.

16. An ultrasound transducer assembly as defined in claim 14, wherein the backing material comprises epoxy resin.