Medical device

• US 8,920,430 B2
• Filed: 08/05/2013
• Issued: 12/30/2014
• Est. Priority Date: 03/31/2004
• Status: Active Grant

• Current Assignee: Merlin MD Pte. Ltd.
• Original Assignee: Merlin MD Pte. Ltd.
• Inventors: Rudakov, Leon, O'Connor, Michael, Gandhi, Deepak
• Primary Examiner(s): STEWART, JASON-DENNIS NEILKEN
• Application Number:
  US13/959,617
• Publication Number:
  US 20140039606A1
• Time in Patent Office: 512 Days
• Field of Search: 606/108, 623 113- 116, 623/1.35
• US Class Current: 606/108
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/065 Y-shaped blood vessels
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/077 having means to fill the space between stent-graft and aneurysm wall, e.g. a sleeve
• CPC Class Codes: A61F 2002/823 Stents, different from stent-grafts, adapted to cover an aneurysm
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2002/91583 by a bridge, whereby at least one of its ends is connected along the length of a strut between two consecutive apices within a band
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes

Abstract

A method for treating an aneurysm can include inserting a medical device partially in a first artery and partially in a third artery. The device can be expanded radially outwardly from a first position to a second position to engage an inner surface of the first artery and an inner surface of the third artery, so as to maintain a fluid pathway through said arteries. Further, the device can be positioned such that, when the device is in the second position, a porous membrane of the device is located at a neck of the aneurysm.

Claims

1. A method for treating a bifurcation or trifurcation aneurysm occurring on a first artery, the first artery and a second artery joining to a third artery, the method comprising:

inserting a medical device such that it is at least partially located in the first artery and is at least partially located in the third artery;

expanding the medical device from a first position to a second position, said medical device is expanded radially outwardly to the second position such that the exterior surface of said medical device engages with the inner surface of the first and third arteries so as to maintain a fluid pathway through said arteries; and

positioning the medical device such that a membrane of the medical device is located against an aneurysm neck of the aneurysm to obstruct blood circulation to the aneurysm when the medical device is expanded to the second position, and at least a portion of the membrane is secured to the medical device to maintain the position of the membrane relative to the medical device when expanded to the second position;

wherein the membrane is permeable and porous, the size of the pores of the membrane and the ratio of the material surface area of the membrane being such that blood supply to perforators and/or microscopic branches of main brain arteries is permitted to improve healing of the first artery but blood supply to the aneurysm is reduced.

2. The method of claim 1, wherein the wall thickness is less than or equal to 0.0028″

.

3. The method of claim 1, wherein the membrane has fabricated pores between 20 and 100 microns in size.

4. The method of claim 1, wherein the distance between adjacent pores does not exceed 75 microns.

5. The method of claim 1, wherein the membrane comprises a plurality of polymeric strips.

6. The method of claim 1, wherein the membrane comprises a mesh.

7. The method of claim 1, wherein the device comprises a generally tubular structure, and wherein the exterior surface of the device is defined by a plurality of interconnected struts having interstitial spaces therebetween.

8. The method of claim 7, wherein the membrane completely surrounds one or more of the plurality of struts.

9. The method of claim 1, wherein the device comprises a stent.

10. The method of claim 1, wherein the medical device comprises (a) an expandable frame having a plurality of struts and (b) a porous membrane that extends around and between the plurality of struts, wherein the membrane comprises a single sheet web portion that extends only in a central region, from a first strut of the plurality of struts to a second strut adjacent to the first strut, the first strut being spaced from the second strut at an interstitial spacing that is greater than a width of the first strut or a width of the second strut, the central region being (i) bounded radially between radially outermost edges and radially innermost edges of the first and second struts and (ii) bounded axially between the first strut and the second strut, the membrane web portion defining a web thickness that is less than a wall thickness of the first strut or a wall thickness of the second strut.

11. A method for treating a bifurcation or trifurcation aneurysm, in a patient, occurring at a first artery, the first artery and a second artery joining to a third artery, the method comprising:

inserting a medical device partially in the first artery and partially in the third artery, the medical device comprising an expandable latticework frame having a plurality of struts that each define a radially outermost edge, a radially innermost edge, and an axial strut width, the radially outermost edge and the radially innermost edge defining a wall thickness therebetween, the medical device further comprising a porous membrane that extends around and between the plurality of struts, the membrane having a web portion that extends only in a central region, from a first strut of the plurality of struts to a second strut adjacent to the first strut, the first strut being spaced from the second strut at an interstitial spacing that is greater than the first or second strut width, the central region being (i) bounded radially between the radially outermost edges and the radially innermost edges of the first and second struts and (ii) bounded axially between the first strut and the second strut, the membrane web portion defining a web thickness that is less than the first or second strut wall thickness;

expanding the device radially outwardly from a first position to a second position such that, when the device is in the second position, a first region of an exterior surface of the device engages an inner surface of the first artery and a second region of the exterior surface of the device engages an inner surface of the third artery, so as to maintain a fluid pathway through said arteries; and

positioning the device such that, when the device is in the second position, the porous membrane, secured to the device, is located at a neck of the aneurysm;

wherein the membrane has a substantially uniform porosity over a length extending from a distal end of the membrane to a proximal end of the membrane, and a distance between adjacent pores of the membrane does not exceed 75 microns; and

wherein, when the device is in the second position and the membrane is positioned at the neck of the aneurysm, the membrane is effective to;

(i) reduce blood supply into the aneurysm, and (ii) permit blood supply through pores of the membrane and into perforators and/or microscopic branches of the first artery so as not to inhibit blood supply functions of the perforators and/or microscopic branches.

12. The method of claim 11, wherein the device comprises a generally tubular structure, and wherein the exterior surface of the device is defined by a plurality of interconnected struts having interstitial spaces therebetween.

13. The method of claim 11, wherein the membrane completely surrounds each of the plurality of struts.

14. The method of claim 11, wherein the membrane comprises a mesh.

15. The method of claim 11, wherein the wall thickness is less than or equal to 0.0028″

.

16. A method for treating an aneurysm, in a patient, the method comprising:

inserting a medical device in a first vessel, the medical device having attached therewith a porous membrane with a substantially uniform porosity, and an expandable latticework frame having a plurality of struts that each define an axial strut width, a radially outermost edge, a radially innermost edge, and a wall thickness defined between the radially outermost edge and the radially innermost edge,

wherein the porous membrane extends around and between the plurality of struts, the membrane having a single sheet web portion that extends only in a central region, from a first strut of the plurality of struts to a second strut adjacent to the first strut, the first strut being spaced from the second strut at an interstitial spacing that is greater than the first or second strut width, the central region being (i) bounded radially between the radially outermost edges and the radially innermost edges of the first and second struts and (ii) bounded axially between the first strut and the second strut, the membrane web portion defining a web thickness that is less than the first or second strut wall thickness;

positioning the device such that the device and membrane is located at a neck of the aneurysm; and

expanding the device radially outwardly from a first position to a second position such that, when the device is in the second position, a distal region of an exterior surface of the device engages an inner surface of the first vessel distal to the aneurysm, a proximal region of the exterior surface of the device engages an inner surface of the first vessel proximal to the aneurysm;

wherein, when the device is in the second position, the membrane comprises pores with a size between about 20 microns and about 100 microns and a distance between adjacent pores that is not larger than 100 microns, such that the membrane reduces blood flow into the aneurysm and permits blood supply to small branch vessels, branching from the first vessel, through the pores of the membrane so as not to inhibit blood supply functions of the small branch vessels.

17. The method of claim 16, wherein the wall thickness is less than or equal to 0.0028″

.

18. The method of claim 16, wherein the membrane completely surrounds the plurality of struts.

19. The method of claim 16, wherein the membrane comprises a mesh.

20. The method of claim 16, wherein the device comprises a generally tubular structure, and wherein the exterior surface of the device is defined by a plurality of interconnected struts having interstitial spaces therebetween.