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US5725494A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and methods for ultrasonically enhanced intraluminal therapy

Assignee: Pharmasonics Inc
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Filing: 1995-11-30
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Granted: 1998-03-10
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Expires: 2015-11-30
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Abstract

Abstract An ultrasonic catheter comprises a catheter body having a resonantly vibrating assembly at its distal end. The resonantly vibrating assembly comprises a tail mass, an interface member, and a spring element which connects the tail mass to the interface member. An interface surface is formed on the interface member and is forwardly disposed at the distal end of the catheter. A longitudinally oscillating driver is disposed between the tail mass and the interface member, and the catheter can be connected to a suitable power supply to induce oscillations in the driver. The driver is typically a piezoelectric device, such as a tubular piezoelectric transducer or a piezoelectric stack. The characteristics of the interface member, spring element, and longitudinally oscillating driver are selected so that the interface member may be resonantly vibrated at an ultrasonic frequency. The catheter is useful for treating luminal conditions, such as vascular clot and plaque. Optionally, a therapeutic agent may be delivered through the catheter simultaneously with the application of ultrasonic energy.

Inventors

  • 👤 Axel F. Brisken

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 12:06
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/22; A61B17/22004; A61B17/22012; A61B17/2202; A61B2017/22021; A61B2017/22038; A61B2017/22082; A61B2017/22084

Claims Analysis

Total Claims: 40
Claim 1
Independent Claim 94 words
A catheter comprising: a catheter body having a proximal end and a distal end; a tail mass attached to the catheter body; a longitudinally oscillating driver engaging and extending distally from the tail mass; an interface member engaging a distally forward surface of the oscillating driver, wherein the mass of the interface member is much less than that of the tail mass; and a spring element connecting the tail mass to the interface member, wherein the spring element has a spring force which is selected to permit resonant driving by the longitudinally oscillating driver.
Claim 2
Dependent Claim 94 words
A catheter comprising: a catheter body having a proximal end and a distal end; a tail mass attached to the catheter body; a longitudinally oscillating driver engaging and extending distally from the tail mass; an interface member engaging a distally forward surface of the oscillating driver, wherein the mass of the interface member is much less than that of the tail mass; and a spring element connecting the tail mass to the interface member, wherein the spring element has a spring force which is selected to permit resonant driving by the longitudinally oscillating driver.
Claim 3
Dependent Claim 27 words
A catheter as in claim 1, wherein the longitudinally oscillating driver comprises a longitudinally oscillating member selected from the group consisting of piezoelectric elements and magnetostrictive elements.
Claim 4
Dependent Claim 26 words
A catheter as in claim 2, wherein the longitudinally oscillating member comprises a hollow piezoelectric cylinder having an inner cylindrical electrode and an outer cylindrical electrode.
Claim 5
Dependent Claim 32 words
A catheter as in claim 3, wherein piezoelectric cylinder has dimensions and is composed of a material which provide oscillation at a frequency in the range from 10 kHz to 300 kHz.
Claim 6
Dependent Claim 54 words
A catheter as in claim 4, wherein the piezoelectric cylinder is composed of a lead zirconate titinate, has a length in the range from 2 mm to 2 cm, an outer diameter in the range from 1 mm to 4 mm, and a wall thickness in the range from 0.1 mm to 0.5 mm.
Claim 7
Dependent Claim 20 words
A catheter as in claim 2, wherein the longitudinally oscillating member comprises a plurality of ceramic disks having electrodes therebetween.
Claim 8
Dependent Claim 25 words
A catheter as in claim 1, wherein the tail mass has a mass which is at least four times the mass of the interface member.
Claim 9
Dependent Claim 38 words
A catheter as in claim 7, wherein the tail mass has a mass in the range from 0.1 gm to 10 gm and the interface member has a mass in the range from 0.01 gm to 1 gm.
Claim 10
Dependent Claim 33 words
A catheter as in claim 1, wherein the spring element comprises at least one rod secured at a proximal end to the tail mass and at a distal end to the interface member.
Claim 11
Dependent Claim 20 words
A catheter as in claim 9, wherein the spring element consists of a single rod disposed coaxially within the catheter.
Claim 12
Dependent Claim 26 words
A catheter as in claim 9, wherein the spring element comprises at least two parallel rod members disposed symmetrically about the axis of the catheter body.
Claim 13
Dependent Claim 31 words
A catheter as in claim 1, wherein the interface member includes a distally disposed interface surface which forwardly transmits longitudinal oscillations into the environment surrounding the distal end of the catheter.
Claim 14
Dependent Claim 15 words
A catheter as in claim 12, wherein the interface surface has a generally convex shape.
Claim 15
Dependent Claim 21 words
A catheter as in claim 1, wherein the catheter body has at least one lumen for delivering a therapeutic agent therethrough.
Claim 16
Dependent Claim 94 words
An improved ultrasonic catheter of the type comprising a catheter body having an ultrasonic driver at a distal end thereof, wherein the improvement comprises an ultrasonic driver comprising: a tail mass secured to the distal end of the catheter body; an interface member distally spaced-apart from the tail mass; a spring element connecting the interface member to the tail mass; an ultrasonic driver disposed between the interface member and the tail mass, wherein said driver oscillates at or near a resonant frequency characteristic of the interface member, the spring element, and the ultrasonic driver.
Claim 17
Dependent Claim 94 words
An improved ultrasonic catheter of the type comprising a catheter body having an ultrasonic driver at a distal end thereof, wherein the improvement comprises an ultrasonic driver comprising: a tail mass secured to the distal end of the catheter body; an interface member distally spaced-apart from the tail mass; a spring element connecting the interface member to the tail mass; an ultrasonic driver disposed between the interface member and the tail mass, wherein said driver oscillates at or near a resonant frequency characteristic of the interface member, the spring element, and the ultrasonic driver.
Claim 18
Dependent Claim 25 words
A catheter as in claim 15, wherein the ultrasonic driver comprises a hollow piezoelectric cylinder having an inner cylindrical electrode and an outer cylindrical electrode.
Claim 19
Dependent Claim 33 words
A catheter as in claim 16, wherein the piezoelectric cylinder has dimensions and is composed of a material which provide oscillation at a frequency in the range from 10 kHz to 300 kHz.
Claim 20
Dependent Claim 54 words
A catheter as in claim 17, wherein the piezoelectric cylinder is composed of a lead zirconate titinate, has a length in the range from 2 mm to 2 cm, an outer diameter in the range from 1 mm to 4 mm, and a wall thickness in the range from 0.1 mm to 0.5 mm.
Claim 21
Dependent Claim 19 words
A catheter as in claim 15, wherein the ultrasonic driver comprises a plurality of ceramic disks having electrodes therebetween.
Claim 22
Dependent Claim 25 words
A catheter as in claim 15, wherein the tail mass has a mass which is at least four times the mass of the interface member.
Claim 23
Dependent Claim 38 words
A catheter as in claim 20, wherein the tail mass has a mass in the range from 0.1 gm to 10 gm and the interface member has a mass in the range from 0.01 gm to 1 gm.
Claim 24
Dependent Claim 33 words
A catheter as in claim 15, wherein the spring element comprises at least one rod secured at a proximal end to the tail mass and at a distal end to the interface member.
Claim 25
Dependent Claim 20 words
A catheter as in claim 22, wherein the spring element consists of a single rod disposed coaxially within the catheter.
Claim 26
Dependent Claim 26 words
A catheter as in claim 22, wherein the spring element comprises at least two parallel rod members disposed symmetrically about the axis of the catheter body.
Claim 27
Dependent Claim 31 words
A catheter as in claim 15, wherein the interface member includes a distally disposed interface surface which forwardly transmits longitudinal oscillations into the environment surrounding the distal end of the catheter.
Claim 28
Dependent Claim 15 words
A catheter as in claim 25, wherein the interface surface has a generally convex shape.
Claim 29
Dependent Claim 21 words
A catheter as in claim 15, wherein the catheter body has at least one lumen for delivering a therapeutic agent therethrough.
Claim 30
Independent Claim 79 words
A method for treating intraluminal lesions, said method comprising: providing a catheter having an assembly comprising an interface member connected to a tall mass by a spring element disposed at its distal end, wherein the assembly has a resonant frequency; advancing a forwardly disposed surface of the interface member to a region near the intraluminal lesion; driving the interface member relative to the tail mass at the resonant frequency, wherein ultrasonic energy is amplified and radiated into the region.
Claim 31
Independent Claim 79 words
A method for treating intraluminal lesions, said method comprising: providing a catheter having an assembly comprising an interface member connected to a tall mass by a spring element disposed at its distal end, wherein the assembly has a resonant frequency; advancing a forwardly disposed surface of the interface member to a region near the intraluminal lesion; driving the interface member relative to the tail mass at the resonant frequency, wherein ultrasonic energy is amplified and radiated into the region.
Claim 32
Dependent Claim 14 words
A method as in claim 28, wherein the intraluminal lesion contains a vascular stenosis.
Claim 33
Dependent Claim 17 words
A method as in claim 29, wherein the interface member surface is engaged against a vascular obstruction.
Claim 34
Dependent Claim 25 words
A method as in claim 28, wherein the interface member is driven at a frequency in the range from about 10 kHz to 300 kHz.
Claim 35
Dependent Claim 25 words
A method as in claim 31, wherein the interface member is driven with a longitudinal amplitude in the range from 0.05 μm to 20 μm.
Claim 36
Dependent Claim 26 words
A method as in claim 28, wherein the forwardly disposed surface has an area in the range from 0.5 mm 2 to 20 mm 2 .
Claim 37
Dependent Claim 19 words
A method as in claim 28, further comprising delivering a therapeutic agent through the catheter to the intraluminal lesion.
Claim 38
Dependent Claim 21 words
A method as in claim 34, wherein the therapeutic agent is delivered while ultrasonic energy is being radiated into the region.
Claim 39
Dependent Claim 22 words
A method as in claim 35, wherein the therapeutic agent is a fibrinolytic agent delivered to a vascular stenosis to treat clot.
Claim 40
Dependent Claim 21 words
A method as in claim 35, wherein the therapeutic agent is delivered to a previously treated vascular site to inhibit restenosis.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-03-09 2001-09-08 2002-03-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-03-09 2005-09-08 2006-03-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-03-09 2009-09-08 2010-03-10 $7700.00 Window Closed / Lapsed

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