UNOBSTRUCTING MICRODEVICES FOR SELF-CLEARING IMPLANTABLE CATHETERS

• US 20110313340A1
• Filed: 06/20/2011
• Published: 12/22/2011
• Est. Priority Date: 06/18/2010
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Judy, Jack W., Bergsneider, Marvin, Lee, Hyowon
• Granted Patent: US 9,604,039 B2
• Time in Patent Office: Days
• US Class Current: 604/8
• CPC Class Codes: A61M 2025/0019 Cleaning catheters or the like, e.g. for reuse of the device, for avoiding replacement
• CPC Class Codes: A61M 25/007 Side holes, e.g. their profiles or arrangements; Provisions to keep side holes unblocked
• CPC Class Codes: A61M 27/006 Cerebrospinal drainage; Accessories therefor, e.g. valves

Abstract

A self-clearing actuator configured to be positioned in a pore providing fluid communication into a central lumen of a ventricular catheter body is described. The actuator extends into a central bore via a cantilever beam having a first end emanating at the central bore and a second end terminating at the actuator, wherein the actuator is configured to reciprocate within the central bore between a first position extending downward at an angle into the central bore and a second position substantially at or above the external surface of the catheter. The cantilever beam is stressed, e.g. via a composite compress layer, such that it is preloaded to nominally curve downward to extend the actuator into the second position. The actuator is preferably a magnet responsive to magnetic field such that the magnetic field drives the actuator toward the first position.

Claims

1. An apparatus for self-clearing a flow pore in a human implant, comprising:

a housing configured to be disposed in a flow pore of the implant;

said housing comprising a central bore spanning between an upper surface and a lower surface of the housing, the central bore providing fluid communication into said flow pore; and

an actuator plate extending from the upper surface of the housing into the central bore via a cantilever beam;

the cantilever beam having a first end emanating at the central bore and a second end terminating at the actuator plate;

the actuator plate configured to reciprocate within the central bore between a first position extending downward at an angle into the central bore and a second position substantially at or above the upper surface of the housing;

wherein the cantilever beam is stressed such that it is preloaded to nominally curve downward to extend the actuator plate in the second position; and

wherein the actuator plate comprises a magnet responsive to magnetic field such that the magnetic field drives the actuator plate toward the first position.

2. An apparatus as recited in claim 1, wherein in the second position the actuator plate and cantilever beam are configured to be substantially parallel with the upper surface.

3. An apparatus as recited in claim 2, wherein in the actuator plate is shaped and sized such that it covers a substantial portion of the central bore in the second position.

4. An apparatus as recited in claim 1:

wherein in the cantilever beam comprises a composite material having a first low-stress layer and a second compressed layer; and

wherein the second compressed layer preloads the cantilever beam to nominally curve in the first position.

5. An apparatus as recited in claim 4, wherein the second layer is sized to have a thickness that controls the angle at which the actuator plate extends into the bore.

6. An apparatus as recited in claim 4, wherein the second layer comprises PECVD silicon nitride.

7. An apparatus as recited in claim 6, wherein the first layer comprises LPCVD silicon nitride.

8. An apparatus as recited in claim 4, wherein the first layer of the cantilever beam, the actuator plate, and the upper surface of the housing are all micro-machined from one contiguous layer of material.

9. An apparatus as recited in claim 1, further comprising:

a second actuator plate extending from the upper surface of the housing into the central bore via a second cantilever beam;

wherein the second actuator plate extends from an opposing end of the central bore from the first actuator plate such that second actuator plate is interdigitating with said first actuator plate.

10. An apparatus as recited in claim 9, wherein the first actuator plate is magnetically charged in a different direction than the first actuator plate, such that the magnetic field causes the second actuator to curve in an opposite direction than the first actuator plate.

11. A self-clearing ventricular catheter, comprising:

a catheter body comprising a central lumen extending from a proximal end to a distal end of the catheter;

one or more pores providing fluid communication into the central lumen of the catheter body;

wherein the one or more pores comprise a central bore extending from an external surface of the catheter to an internal surface of the catheter;

the one or more pores comprising a self-clearing actuator;

the actuator extending into the central bore via a cantilever beam;

the cantilever beam having a first end emanating at the central bore and a second end terminating at the actuator;

the actuator configured to reciprocate within the central bore between a first position extending downward at an angle into the central bore and a second position substantially at or above the external surface of the catheter;

wherein the cantilever beam is stressed such that it is preloaded to nominally curve downward to extend the actuator into the second position; and

wherein the actuator comprises a magnet responsive to magnetic field such that the magnetic field drives the actuator toward the first position.

12. A ventricular catheter as recited in claim 11, wherein in the second position the actuator and cantilever beam are configured to be substantially parallel with the external surface.

13. A ventricular catheter as recited in claim 11:

wherein in the cantilever beam comprises a composite material having a first low-stress layer and a second compressed layer; and

wherein the second compressed layer preloads the cantilever beam to nominally curve in the first position.

14. A ventricular catheter as recited in claim 13, wherein the second layer is sized to have a thickness that controls the angle at which the actuator plate extends into the bore.

15. A ventricular catheter as recited in claim 13, wherein the second layer comprises PECVD silicon nitride and the first layer comprises LPCVD silicon nitride.

16. A ventricular catheter as recited in claim 11, further comprising:

a second actuator extending from the upper surface of the housing into the central bore via a second cantilever beam;

wherein the second actuator extends from an opposing end of the central bore from the first actuator such that second actuator is interdigitating with said first actuator.

17. A ventricular catheter as recited in claim 16, wherein the first actuator is magnetically charged in a different direction than the first actuator, such that the magnetic field causes the second actuator to curve in an opposite direction than the first actuator.

18. A shunt system configured for diverting cerebrospinal fluid (CSF) from a ventricle of the brain, comprising:

a ventricular catheter having proximal end and a distal end;

tubing coupled to the distal end of the ventricular catheter;

said tubing having a length sufficient to extend from the ventricle into an abdominal region of the patient;

the ventricular catheter comprising a central lumen extending from a proximal end to a distal end of the catheter;

the ventricular catheter comprising one or more pores each comprising a central bore extending from an external surface of the catheter to an internal surface of the catheter;

the one or more pores providing fluid communication of CSF from the ventricle into the central lumen of the catheter;

the one or more pores comprise a self-clearing actuator;

the actuator extending into the central bore via a cantilever beam;

the cantilever beam having a first end emanating at the central bore and a second end terminating at the actuator;

the actuator configured to reciprocate within the central bore between a first position extending downward at an angle into the central bore and a second position substantially at or above the external surface of the catheter;

wherein the cantilever beam is stressed such that it is preloaded to nominally curve downward to extend the actuator into the second position; and

wherein the actuator comprises a magnet responsive to magnetic field such that the magnetic field drives the actuator toward the first position.

19. A system as recited in claim 18, wherein in the second position the actuator and cantilever beam are configured to be substantially parallel with the external surface.

20. A system as recited in claim 19:

wherein in the cantilever beam comprises a composite material having a first low-stress layer and a second compressed layer; and

wherein the second compressed layer preloads the cantilever beam to nominally curve in the first position.

21. A system as recited in claim 18, further comprising:

a second actuator extending from the upper surface of the housing into the central bore via a second cantilever beam;

wherein the second actuator extends from an opposing end of the central bore from the first actuator such that second actuator is interdigitating with said first actuator.

22. A system as recited in claim 21, wherein the first actuator is magnetically charged in a different direction than the first actuator, such that the magnetic field causes the second actuator to curve in an opposite direction than the first actuator.