Electroactive polymer actuated cerebrospinal fluid shunt

• US 20080125690A1
• Filed: 09/24/2007
• Published: 05/29/2008
• Est. Priority Date: 09/24/2006
• Status: Active Grant

• Current Assignee: Aniteal Laboratories, LLC
• Original Assignee: Aniteal Laboratories, LLC
• Inventors: Delaporte, Stephen E.
• Granted Patent: US 8,211,051 B2
• Time in Patent Office: Days
• US Class Current: 604/9
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61M 2205/0283 Electro-active polymers [EAP]
• CPC Class Codes: A61M 27/006 Cerebrospinal drainage; Accessories therefor, e.g. valves

Abstract

A cerebrospinal fluid (CSF) shunt comprises a ventricular catheter and an electroactive polymer actuated valve for regulating the drainage rate of CSF from the brain ventricle of a patient. The shunt system also comprises a distal catheter for discharge of the CSF to a separate location in the patient'"'"'s body such as the peritoneal cavity or atrium of the heart. The electroactive polymer actuated valve regulates the flow rate of CSF through a predetermined threshold pressure, which can be adjusted and programmed externally from the patient'"'"'s body by means of an external control unit signal, as well as through a signal indicated by an internal sensor or an electroactive polymer transducer. The sensor also communicates a signal to the external control unit for indicating the internal pressure at a single location or multiple locations throughout the fully implanted shunt assembly.

Claims

1. A cerebrospinal fluid shunt system comprising:

A valve having an electroactive polymer for said cerebrospinal shunt system, such that said electroactive polymer is an actuating element;

An electoactive polymer transducer coupled to said valve, such that said electroactive polymer transducer is used as a pressure sensor;

An internal control unit for processing said electroactive polymer transducer;

An external control unit for programming the threshold pressure of said electroactive polymer;

Whereby when the electroactive polymer transducer detects a change in pressure within the shunt assembly, the electroactive polymer transducer pressure provides an electrical voltage to the internal and external control unit, which provides a signal to the electroactive polymer actuator to adjust the valve pressure.

3. The implantable shunt system as in claim 1, wherein the electroactive polymer actuated valve includes a ventricular catheter coupled to an inlet aperture of the valve and a distal catheter coupled to an outlet aperture of the valve.

4. The implantable shunt system as in claim 1, further comprising an external control unit for adjusting the threshold pressure externally from the body.

5. The implantable shunt system as in claim 1, further comprising a transducer for sensing pressure created by the CSF, wherein the sensed pressure is used to adjust the threshold pressure.

2. A shunt system implantable in a body comprising:

an electroactive polymer actuated valve for the control and regulation of cerebrospinal fluid (CSF) being redirected from the brain ventricle to a secondary cavity within the body, the electroactive polymer actuated valve having an adjustable threshold pressure to regulate a flow rate of CSF.

6. The implantable shunt system as in claim 2, further comprising an electroactive polymer transducer for sensing pressure created by the CSF, wherein the sensed pressure is used to adjust the threshold pressure.

7. The implantable shunt system as in claim 6, wherein the differential pressure between the ventricular catheter and the distal catheter results in a deflection of the electroactive transducer which provides a voltage signal for actuating the valve.

8. The implantable shunt system as in claim 7, wherein voltage signal created by the deflection is transmitted to an external control unit outside of the body.

9. The implantable shunt system as in claim 2, wherein valve further comprises:

a ball and spring member disposed at the inlet aperture for controlling the flow rate through the valve; and

an electroactive polymer actuated sliding element disposed in a primary valve chamber configured for actuating the ball and spring member.

10. The implantable shunt system as in claim 9, wherein the inlet aperture includes at least one opening to provide a filtering effect.

11. The implantable shunt system as in claim 2, wherein valve further comprises:

at least one actuated sliding element disposed in the inlet aperture to control the flow rate through the valve; and

an electroactive polymer actuator configured to actuate the at least one sliding element by rotational actuation.

12. The implantable shunt system as in claim 2, wherein valve further comprises:

a shell including a single linearly fixed guide for supporting at least one electroactive polymer element;

the at least one electroactive polymer element disposed in the guide and configured to move along the linearly fixed guide to adjust the threshold pressure; and

an actuator coupled to the at least one electroactive polymer element to control the flow rate through the valve.

13. The implantable shunt system as in claim 12, wherein the linearly fixed guide includes embedded slots for the electroactive polymer element to rest upon when the threshold pressure and flow control is set to a different level.

14. A shunt system implantable in a body comprising:

at least one catheter for draining fluid from a first portion of the body to a second portion of the body; and

at least two electroactive polymer actuated valves disposed with a predetermined distance apart from each other in the catheter.

15. The implantable shunt system as in claim 14, wherein the at least one catheter further comprises at least one outlet port disposed between the at least two spaced apart valves.

16. A shunt system implantable in a body comprising:

an electroactive polymer actuated means for the control and regulation of cerebrospinal fluid (CSF) being redirected from the brain ventricle to a secondary cavity within the body, the electroactive polymer actuated means having an adjustable threshold pressure to regulate a flow rate of CSF;

means for sensing pressure created by the CSF and generating a signal indicative of the pressure; and

control means for receiving the pressure signal and controlling the electroactive polymer actuated means based on the sensed pressure.

17. The implantable shunt system as in claim 16, further comprising an external control means for adjusting the threshold pressure externally from the body.

18. The implantable shunt system as in claim 16, wherein the means for sensing creates a signal readable externally from the body.

19. The implantable shunt system as in claim 16, further comprising a means for filtering the CSF flowing through the electroactive polymer actuated means.

20. The implantable shunt system as in claim 16, further comprises a catheter having one end disposed in the brain ventricle and a second end disposed in the secondary cavity within the body and at least two electroactive polymer actuated means.