DEVICES AND METHODS FOR REMOVAL OF ACUTE BLOCKAGES FROM BLOOD VESSELS

• US 20160015402A1
• Filed: 03/12/2014
• Published: 01/21/2016
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Neuravi Limited (Johnson & Johnson)
• Original Assignee: Neuravi Limited (Johnson & Johnson)
• Inventors: BRADY, Eamon, GILVARRY, Michael, HARDIMAN, David, VALE, David, CASEY, Brendan
• Granted Patent: US 10,357,265 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2017/00867 shape memory effect
• CPC Class Codes: A61B 2017/00942 hydrophilic
• CPC Class Codes: A61B 2017/00951 adhesive
• CPC Class Codes: A61B 2017/22034 for gripping the obstruction or the tissue part from inside
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop
• CPC Class Codes: A61B 2017/2217 single wire changing shape to a gripping configuration
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: B05D 1/322 Removable films used as masks
• CPC Class Codes: B05D 3/12 by mechanical means

Abstract

A clot retrieval device comprises an elongate shaft 104 and an expandable clot retrieval element 2101 on the shaft, the clot retrieval element comprising a framework formed from a substrate material such as Nitinol and having a plurality of struts 2105 and crowns 2102, at least some of the struts 2105 comprises at least one widened portion 2104 of the substrate material to provide enhanced radiopacity. The framework is coated with a radiopaque material such as gold. The device is rendered radiopaque with reduced damping effects.

Claims

1. A clot retrieval device comprising an elongate shaft and an expandable clot engaging element on the shaft, the clot engaging element comprising a framework formed from a substrate material and having a plurality of struts and crowns, at least some of the struts comprising at least one widened portion of the substrate material to provide enhanced radiopacity.

2. A clot retrieval device as claimed in claim 1 wherein the strut comprises a plurality of widened portions which are spaced-apart along a length of the strut.

3. A clot retrieval device as claimed in claim 1 wherein the widened portion of the strut is at least 50%, at least 75%, at least 100%, at least 125%, at least 150%, at least 175%, at least 200%, at least 300% wider than the regions along the length of the strut between the widened portions.

4. A clot retrieval device as claimed in claim 1 wherein the widened portions have a length which is less than 100%, less than 75%, less than 50%, less than 25% of the length of the regions of the strut between the widened portions.

5. A clot retrieval device as claimed in claim 1 wherein the length of the regions of the strut between the widened portions is greater than 300%, greater than 400%, greater than 500%, greater than 600%, greater than 700%, greater than 800%, greater than 900% of the width of the strut.

6. A clot retrieval device as claimed in claim 1 wherein the clot engaging element is cut from a tube of uniform thickness.

7. A clot retrieval device as claimed in claim 1 wherein at least a portion of the framework is coated with a radiopaque material.

22. A device as claimed in claim 1 wherein the substrate material has a density of less than 10 g/cm³, optionally less than 8 g/cm³.

24. A device as claimed in claim 1 wherein the substrate material is a superelastic material such as Nitinol or other super or pseudo elastic metallic alloy.

25. A device as claimed in claim 7 wherein the coating material is Gold, Tantalum, Tungsten, Platinum or an alloy of one of these elements or other dense element or alloy containing one or more radiodense elements.

26. A device as claimed in claim 7 wherein the coating material comprises a polymer or adhesive filled with a dense or high atomic number material such as Barium Sulphate, Bismuth SubCarbonate, Barium OxyChloride, Gold, Tungsten, Platinum or Tantalum.

27. A device as claimed in claim 7 wherein the coating material is applied using an electroplating process, a dipping process, a plasma deposition process, an electrostatic process, a dip or spray coating process, a sputtering process, a soldering process, a cladding process or a drawing process.

8. A clot retrieval device comprising an elongate shaft and an expandable section, the expandable section comprising a framework of strut elements and connections between the strut elements, the framework being formed from a substrate material, wherein at least some of the strut elements have enhanced radiopacity with respect to the radiopacity of the connection between the strut elements.

9. A clot retrieval device as claimed in claim 8 wherein the connections comprise crown elements.

10. A clot retrieval device as claimed in claim 8 comprising a first coating on at least portion of the strut elements.

11. A clot retrieval device as claimed in claim 9 comprising a second coating on at least portion of the crown elements.

12. A clot retrieval device as claimed in claim 9 to 11 comprising a first coating on the strut elements and a second coating on the crown elements.

13. A clot retrieval device as claimed in claim 12 wherein the first and second coatings are of the same material.

14. A clot retrieval device as claimed in claim 12 wherein the first and second coatings are of different materials.

15. A clot retrieval device as claimed in claim 12 wherein the thickness of the first coating varies along a length of a strut element.

20. A clot retrieval device as claimed in claim 14 wherein at least a portion of the framework is coated with a radiopaque material such as gold.

16. A clot retrieval device comprising an elongate shaft and an expandable clot engaging element mounted on the shaft, the clot engaging element having a collapsed delivery configuration and an expanded deployed configuration, the clot engaging element comprising a framework formed from a substrate material of a shape memory material and having a plurality of struts and crowns, at least some of the struts and crowns being of corrugated profile along the length thereof to increase the surface area of the clot engaging element.

17. A clot retrieval device as claimed in claim 16 wherein the struts and crowns comprise a plurality of curved ribs extending along the longitudinal length thereof.

18. A clot retrieval device as claimed in claim 17 wherein the pitch of the ribs is from 10% to 300%, from 10% to 200%, from 10% to 100%, from 20% to 50% of the wall thickness of the struts.

19. A clot retrieval device as claimed in claim 17 wherein the ribs comprise a bend radius between 5 and 125 microns, between 5 and 100 microns, between 5 and 50 microns, between 10 and 30 microns.

21. A clot retrieval device comprising an elongate shaft and an expandable section, the expandable section comprising a framework of interconnected strut elements, the connection region between adjacent strut elements comprising crown elements, said framework formed from a substrate material, at least a portion of a plurality of said strut elements coated with a coating material, and at least a portion of a plurality of said crown elements not coated with said coating material.

23. A device as claimed in claim 21 wherein the coating material has a density of more than 10 g/cm³, optionally more than 15 g/cm³, optionally more than 18 g/cm³.

28. A method of manufacturing the expandable body of a clot retrieval device, the expandable body comprising a substrate material and a coating material, the method comprising:

a first step of applying the coating material to the substrate material,

a second step of removing at least a portion of said coating material from at least one area of said substrate material,

and a third step of cutting away regions of both coating and substrate material to form an interconnected pattern of coated and uncoated regions.

29. A clot retrieval device comprising an elongate shaft and an expandable section, the expandable section formed from a substrate material, at least a portion of the substrate material coated with a first coating material and at least a portion of the first coating material coated with a second coating material.

30. A clot retrieval device comprising an elongate shaft and an expandable member, the expandable member comprising a proximal section, a body section and a distal section, the body section comprising a metallic framework of a first (or substrate) material, the metallic framework comprising a plurality of strut elements, said strut elements comprising an outer surface, an inner surface and side wall surfaces, at least one of said surfaces comprising a smooth surface and recessed features, at least some of said recessed features at least partially filled with a second (coating) material.

31. A method of manufacturing the expandable body of a clot retrieval device, the expandable body comprising a substrate material and a coating material, the method comprising:

a first step of removing material from discrete areas of the substrate material to form recesses, a second step of applying the coating material to the substrate material and recesses, and a third step of removing some or all of the coating from the non-recessed areas of the substrate.

32. A method of applying a radiopaque coating to selective areas of the expandable body of a clot retrieval device, the method involving a masking material and comprising:

a first step of applying a masking material to selective areas of the expandable body,

a second step of applying a coating material to the expandable body,

and a third step of removing the masking material from the expandable body.

33. A method of manufacturing the expandable body of a clot retrieval device, the expandable body comprising a substrate material and a coating material, the method involving a masking material and comprising:

a first step of applying the masking material to the substrate material,

a second step of removing at least a portion of said masking material from at least one area of said substrate material,

a third step of cutting away regions of both masking and substrate material to form an expandable body with masked and unmasked regions,

a fourth step of applying a coating material to the expandable body, such that the coating material adheres to the unmasked areas but does not adhere to the masked areas of the expandable body,

and a fifth step of removing the masking material from the expandable body.

34. A clot retrieval device comprising an expandable body and an elongate shaft, the expandable body comprising a proximal section, a body section and a distal section, the body section comprising a framework of strut elements and at least one fibre assembly, the fibre assembly comprising a radiodense material.