IMPLANTABLE INFUSION DEVICE AND RESERVOIR FOR SAME

• US 20030050623A1
• Filed: 12/26/2001
• Published: 03/13/2003
• Est. Priority Date: 09/07/2001
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Lord, Peter C., Gibson, Scott R., Brandt, William A.
• Granted Patent: US 6,652,510 B2
• Time in Patent Office: Days
• US Class Current: 604/891.1
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/14586 pressurised by means of a flexible diaphragm
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

An implantable infusion device includes of a disc-shaped housing that is made from a biocompatible material. The housing contains a reservoir for holding a volume of infusion medium, such as a medication to be administered to the patient. A reservoirs for an implantable infusion devices may be configured to reduce the thickness requirements of the device, without compromising volume capacity of the device. In addition, such a reservoir configuration can allow multiple dispensing and fill or re-fill operations, with reduced risk of damage to the reservoir components. The reservoir defines a chamber that contains at least one flexible diaphragm. Each diaphragm has an outer peripheral edge within the chamber, a convolution adjacent the peripheral edge and a generally smooth central portion that is free to flex within the chamber, wherein the convolution enhances the flexibility of the diaphragm. A ring is provided in alignment with the peripheral edge of each diaphragm. The ring has a central opening that is aligned with the convolution and central portion of each diaphragm, to allow the diaphragm to flex within the ring. In this manner, the volume on one side of each diaphragm may be varied to correspond to a varying volume of infusion medium. Similarly, the volume within the reservoir chamber on the other side of the diaphragms is varied as the diaphragms flex, to correspond to the expansion and contraction of a propellant medium within the reservoir.

Claims

1. An implantable infusion device for delivering infusion medium, the device comprising:

a housing having a reservoir section and an outlet;

a reservoir disposed within the reservoir section of the housing and coupled in fluid flow communication with the outlet, the reservoir defining a chamber that contains at least one flexible diaphragm, each diaphragm having an outer peripheral edge within the chamber, a convolution adjacent the peripheral edge and a generally flat central portion that is free to flex within the chamber, wherein the convolution enhances the flexibility of the diaphragm.

2. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises a pair of diaphragms.

3. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises first and second diaphragms and wherein the reservoir further contains a spacer disposed between the first and second diaphragms, to space the peripheral edge of the first diaphragm from the peripheral edge of the second diaphragm.

4. An implantable infusion device as recited in claim 3, wherein the spacer comprises a ring having a central opening to allow the central portions of the diaphragms to flex toward each other.

5. An implantable infusion device as recited in claim 1, wherein each diaphragm comprises a disc-shaped member having an annular peripheral edge and wherein the convolution of each diaphragm comprises an annular convolution disposed adjacent the annular peripheral edge of the diaphragm.

6. An implantable infusion device as recited in claim 1, wherein the reservoir further contains a ring disposed in alignment with the peripheral edge of each diaphragm, the ring having a central opening arranged in alignment with the convolution and the central portion of each diaphragm, to allow the central portion of each diaphragm to flex within the central opening of the ring.

7. An implantable infusion device as recited in claim 6, wherein the ring defines an inner peripheral edge and the convolution on each diaphragm is arranged immediately adjacent the inner peripheral edge of the ring.

8. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises a pair of diaphragms and wherein the reservoir further contains a ring disposed in alignment with the peripheral edge of each diaphragm, the ring having a central opening arranged in alignment with the convolution and the central portion of each diaphragm, to allow the central portion of each diaphragm to flex within the central opening of the ring toward the other diaphragm.

9. An implantable infusion device as recited in claim 8, wherein the ring defines an inner peripheral edge and the convolution on each diaphragm is arranged immediately adjacent the inner peripheral edge of the ring.

10. An implantable infusion device as recited in claim 1, wherein the reservoir section of the housing comprises an outer ring, a first cover disposed on one side of the outer ring and a second cover disposed on the opposite side of the outer ring to define an open interior between the first and second covers and within the outer ring, and wherein the reservoir chamber is provided within the open interior of the reservoir section.

11. An implantable infusion device as recited in claim 1, wherein:

the at least one diaphragm comprises a pair of diaphragms;

the reservoir further contains an inner ring disposed in alignment with the peripheral edge of each diaphragm, the inner ring having a central opening arranged in alignment with the convolution and the central portion of each diaphragm, to allow the central portion of each diaphragm to flex within the central opening of the inner ring toward the other diaphragm;

the reservoir section of the housing comprises an outer ring, a first cover disposed on one side of the outer ring and a second cover disposed on the opposite side of the outer ring to define an open interior located between the first and second covers and within the outer ring, and

the pair of diaphragms and the inner ring are provided within the open interior of the reservoir section.

12. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises a pair of diaphragms and wherein the peripheral edges of the pair of diaphragms are coupled together, while the convolution and central portion of each diaphragm is free to flex relative to the other diaphragm.

13. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises a pair of diaphragms defining a variable volume therebetween and wherein the outlet is coupled in fluid flow communication with the volume between the diaphragms.

14. An implantable infusion device as recited in claim 13, wherein a propellant medium is provided in the portion of the reservoir chamber that is not between the two diaphragms.

15. An implantable infusion device as recited in claim 13, further comprising a drive mechanism for driving fluid out of the volume between the diaphragms and through the outlet.

16. An implantable infusion device as recited in claim 13, further comprising an inlet for receiving infusion medium, the inlet provided in fluid flow communication with the volume between the diaphragms.

17. An implantable infusion device as recited in claim 1, wherein the at least one diaphragm comprises a pair of diaphragms defining a variable volume in the portion of the reservoir chamber that is not between the two diaphragms and wherein the outlet is coupled in fluid flow communication with the portion of the reservoir chamber that is not between the two diaphragms.

18. An implantable infusion device as recited in claim 17, wherein a propellant medium is provided in the portion of the reservoir chamber between the two diaphragms.

19. An implantable infusion device as recited in claim 17, further comprising a drive mechanism for driving fluid out of the portion of the reservoir chamber that is not between the two diaphragms and through the outlet.

20. An implantable infusion device as recited in claim 17, further comprising an inlet for receiving infusion medium, the inlet provided in fluid flow communication with the portion of the reservoir chamber that is not between the two diaphragms.

21. An implantable infusion device as recited in claim 1, wherein the reservoir section of the housing comprises a cover having a curved inner surface, and wherein the at least one diaphragm comprises a diaphragm having a curved central portion having a curvature that substantially matches the curvature of the curved inner surface of the cover.

22. A process of making an implantable infusion device, the process comprising:

providing a first diaphragm having a peripheral edge, a convolution adjacent the peripheral edge and a generally smooth central portion;

providing an inner ring having a central opening;

arranging the first diaphragm adjacent one side of the inner ring with the peripheral edge of the first diaphragm aligned with the inner ring and the convolution and central portion of the first diaphragm aligned with the central opening of the inner ring;

disposing the aligned first diaphragm and inner ring in a reservoir chamber; and

providing an outlet in fluid flow communication with one side of the first diaphragm.

23. A process as recited in claim 22, further comprising:

disposing an infusion medium on said one side of the first diaphragm; and

disposing a propellant medium on the opposite side of the first diaphragm.

24. A process as recited in claim 22, further comprising:

providing a second diaphragm having a peripheral edge, a convolution adjacent the peripheral edge and a generally smooth central portion;

arranging the second diaphragm adjacent the opposite side of the inner ring with the peripheral edge of the second diaphragm aligned with the inner ring and the convolution and central portion of the second diaphragm aligned with the central opening of the inner ring; and

disposing the aligned second diaphragm within the chamber,

wherein a first variable volume is defined between the first and second diaphragms and a second variable volume is defined as the portion of the reservoir chamber that is not between the first and second diaphragms.

25. A process as recited in claim 24, further comprising:

disposing an infusion medium in the first variable volume; and

disposing a propellant medium in the second variable volume.

26. A process as recited in claim 24, further comprising:

disposing a propellant medium in the first variable volume; and

disposing an infusion medium in the second variable volume.