Flexible and steerable device

• US 10,441,746 B2
• Filed: 09/02/2016
• Issued: 10/15/2019
• Est. Priority Date: 09/04/2015
• Status: Active Grant

• Current Assignee: Petrus A. Besselink
• Original Assignee: Petrus A. Besselink
• Inventors: Besselink, Petrus A.
• Primary Examiner(s): Severson, Ryan J.
• Application Number:
  US15/756,729
• Publication Number:
  US 20190060612A1
• Time in Patent Office: 1,138 Days
• CPC Class Codes: A61B 1/0056 the insertion parts being asymmetric, e.g. for unilateral bending mechanisms
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/00309 Cut-outs or slits
• CPC Class Codes: A61B 2017/00331 with preformed bends
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61M 2025/0063 having means, e.g. stylets, mandrils, rods or wires to reinforce or adjust temporarily the stiffness, column strength or pushability of catheters which are already inserted into the human body
• CPC Class Codes: A61M 25/0013 Weakening parts of a catheter tubing, e.g. by making cuts in the tube or reducing thickness of a layer at one point to adjust the flexibility
• CPC Class Codes: A61M 25/0051 made from fenestrated or weakened tubing layer
• CPC Class Codes: A61M 25/0053 having a variable stiffness along the longitudinal axis, e.g. by varying the pitch of the coil or braid
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 25/0102 Insertion or introduction using an inner stiffening member, e.g. stylet or push-rod
• CPC Class Codes: A61M 25/0138 having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61M 25/04 in the body, e.g. expansible A61M25/10, A61M16/0488 take precedence
• CPC Class Codes: A61M 25/09041 Mechanisms for insertion of guide wires
• CPC Class Codes: A61M 25/104 : used for angioplasty
• CPC Class Codes: A61M 27/00 : Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202
• CPC Class Codes: A61M 29/00 : Dilators with or without means for introducing media, e.g. remedies instruments for performing visual medical inspections of cavities or tubes of the body A61B1/00

Abstract

A device, a method of making a device and a method of inserting a device into a tubular path. The device includes a tubular sheath with one or more helical slots formed therein and a control element that fits within the sheath. In one form, the device is an endoluminal device that simultaneously improves flexibility and structural rigidity though variations in one or both of slot width along the length of the slot and slot pitch along the length of the tubular sheath. When the operator pulls at the proximal end of the control element while holding the outer sheath in place, the slots will tend to close in a preferential manner such that more precise control of device length and bending is enabled, while simultaneously providing improvements in structural rigidity during device insertion and navigation through a body lumen or related tubular member where tortuous paths may be encountered along the member path.

Claims

1. A steerable device comprising:

a tubular sheath comprising;

a proximal end;

a distal end opposite the proximal end; and

at least one reconfigurable section disposed intermediate the proximal and distal ends and possessive of an increased flexibility, the at least one reconfigurable section comprising at least one helical slot formed through the wall thereof, the at least one helical slot defining;

a pitch along the axial dimension of the tubular sheath; and

a pattern with a periodically-varying width along a length axis of the tubular sheath; and

an elongate control element defining a proximal end and a distal end, the control element attached to at least one part of the tubular sheath in order to enable an operator to vary the length of the tubular sheath by imposing a force to the control element that also causes a relative tangential rotation between adjacent wall sections that define the slot, resulting in a known, limited, controllable torsional rotation of the distal end of the tubular sheath without torsional rotation of the proximal end of the tubular sheath.

2. The device of claim 1, wherein the helical slot further defines a plurality of interlocking members having a nesting shape fit between adjacent wall sections defined within the tubular sheath.

3. The device of claim 1, wherein the at least one reconfigurable section bends upon increasing force imparted by the control element to the tubular sheath.

4. The device of claim 3, wherein applying a certain preload causes effects comprising reducing the floppiness of the reconfigurable sections, tangential rotation of at least one reconfigurable section and bending of at least one reconfigurable section.

5. The device of claim 1, wherein locking members limit the relative tangential rotation between adjacent coils to a desirable and controllable maximum value.

6. The device of claim 5, wherein applying a certain preload causes effects comprising reducing the floppiness of the reconfigurable sections, tangential rotation of at least one reconfigurable section and bending of at least one reconfigurable section.

7. The device of claim 1, wherein the tangential rotation is compensated by using two reconfigurable sections, a first one with a clockwise helical cut and a second one with a counterclockwise helical cut.

8. The device of claim 1, wherein pure torsional rotation is achieved by supporting a certain part of the helical section with an internal or external guiding member that prevents bending of the part of the helical section.

9. The device of claim 8, wherein the guiding member has a shape comprising a curvature in one or more planes with an angle between 0 and 180 degrees.

10. The device of claim 9, wherein the guiding member is integrated with the elongate control element.

11. The device of claim 8, wherein the guiding member is integrated with the elongate control element.

12. The device of claim 1, wherein the control element has a tubular shape, thus enabling an operator to reach the distal end through the lumen in the control element.

13. The device of claim 1, further comprising an endoluminal device configured to slidably fit over the tubular sheath.

14. The device of claim 13, wherein at least a part of the endoluminal device is selected from the group consisting of a catheter, steerable tip, endoscope, laser system, ablation system, stent, angioplasty balloon, drain, dilator, filter, basket, filterbasket, anchor, floating anchor, occlusion device, guide wire, stylet, electrode, lead, catheter sheath for use with catheter introducers or a drug infusion catheter, and combinations thereof.

15. The device of claim 1, further comprising an endoluminal device configured to slidably fit through the control element.

16. The device of claim 15, wherein at least a part of the endoluminal device is selected from the group consisting of a catheter, steerable tip, endoscope, laser system, ablation system, stent, angioplasty balloon, drain, dilator, filter, basket, filterbasket, anchor, floating anchor, occlusion device, guide wire, stylet, electrode, lead, catheter sheath for use with catheter introducers or a drug infusion catheter, and combinations thereof.

17. The device of claim 1, wherein at least a part of the device is selected from the group consisting of minimal invasive devices, surgical tools, steerable drilling tools, instruments, rotating instruments, placement of pacemaker leads and implants, comprising using a catheter, steerable tip, endoscope, laser system, ablation system, stent, angioplasty balloon, drain, dilator, filter, basket, filterbasket, anchor, floating anchor, occlusion device, guide wire, stylet, electrode, lead, catheter sheath for use with catheter introducers or a drug infusion catheter, and combinations thereof.

18. The device of claim 17, further comprising a tool coupled to at least one of the control element or the tubular sheath, the tool configured to regulate relative axial positions between the control element and the tubular sheath and thereby effect a transition in the shape of at least one of the reconfigurable sections, comprising one of the effects selected from bending, reducing flexibility, improving pushability, locking to prevent torsion, active torsion by tension and combinations thereof.

19. The device of claim 18, wherein the tool comprises indicia configured to apprise a user of an amount of deformation of the reconfigurable sections.

20. The device of claim 18, wherein the tool comprises a connector to facilitate removable attachment of the tool to the at least one of the control element or the tubular sheath.

21. The device of claim 18, wherein the tool comprises a display configured to inform an operator about an operational status of the reconfigurable section.

22. The device of claim 1, wherein the elongate control element is made of at least one of a composite, a polymer wire, a polymer strip, a polymer tube, a metal wire, a metal strip, a metal tube, a tube or wire of a shape memory alloy with shape memory, linear elasticity, superelasticity, and combinations thereof.

23. The device of claim 1, wherein the proximal end of the control element is located near the proximal end of a reconfigurable section.

24. The device of claim 23, wherein the control element is activated by a remote controlled actuator, working on a principle comprising a shape memory effect, hydraulic pressure, electric or magnetic signal, electromotor, direct or with a lever or mechanical gear box and combinations thereof.

25. The device of claim 1, comprising steerable devices selected from the group consisting of a drilling tool, a robot arm, beam or antenna for use in outer space or under water, manipulators in aircraft, submarines, drones, robotics, vacuum environments, laboratory equipment and other fields, endoluminal use in water, oil and gas exploration and production and combinations thereof.

26. The device of claim 1, wherein a change in shape of the reconfigurable section comprises a change into a state that is suitable for inserting, steering into and being removable from a body lumen.

27. The device of claim 1, wherein the periodically-varying width of the pattern is configured so that a change in length of the tubular sheath causes at least one of distal end bending, improved pushability, improved torquability and reduced flexibility therein.

28. The device of claim 27, wherein the bending of the at least reconfigurable section comprises bending in only one plane.

29. The device of claim 27, wherein the bending of the at least reconfigurable section comprises bending in more than one plane.

30. The device of claim 27, wherein the bending of the at least reconfigurable section comprises bending in a helical shape.

31. The device of claim 27, wherein the bending of the at least reconfigurable section comprises bending in a pig-tail shape.

32. The device of claim 1, wherein the pitch defined along the tubular sheath axial dimension is constant.

33. The device of claim 1, wherein the pitch defined along the tubular sheath axial dimension is variable.

34. The device of claim 1, wherein the helical slot has a pattern with alternating minimum and maximum slot width, the locations with minimum slot width located on a line parallel to the tubular sheath axial dimension.

35. The device of claim 34, wherein the change in length is a shortening such that the minimum slot width becomes closed while the maximum slot width remains open through at least a portion of the change in length, the closed condition of the minimum slot width resulting in a decrease of the axial flexibility of at least the respective portion of the tubular sheath.

36. The device of claim 35, wherein further increasing the imposed force in the control element causes closure of portions of the tubular sheath that are circumferentially opposite of the minimum slot width along with an increased bending of the reconfigurable section, while axial flexibility of the tubular sheath is further reduced until all slots are fully closed when the bending is complete.

37. The device of claim 1, wherein the periodically-varying width pattern defines alternating minimum and maximum slot width, the locations with minimum slot width located on a line that is not parallel to the tubular sheath axial dimension.

38. The device of claim 37, wherein the change in length is a shortening such that the minimum slot width becomes closed while the maximum slot width remains open through at least a portion of the change in length, the closed condition of the minimum slot width resulting in a decrease of the axial flexibility of at least the respective portion of the tubular sheath.

39. The device of claim 38, wherein further increasing the imposed force in the control element causes closure of portions of the tubular sheath that are circumferentially opposite of the minimum slot width along with an increased bending of the reconfigurable section, while axial flexibility of the tubular sheath is further reduced until all slots are fully closed when the bending is complete.

40. The device of claim 1, wherein the periodically-varying width along at least a portion of the helical slot length comprises at least one of (a) interlocking members having a nesting shape fit and (b) interruptions in the helical slot that define at least one tangential torsional rigidity-enhancing hinge.

41. The device of claim 40, wherein a change in shape in response to an operator imposing a force to the control element to enable the operator to vary the length of the tubular sheath comprises a shortening of the portion of the tubular sheath that defines the hinges, such shortening causes a gradual closure of the opposing slots and a bending of the respective portion of the tubular sheath.

42. The device of claim 40, wherein a shortening of the section comprising the interlocking members causes a closure of the gap around the locking members, resulting in at least one of a reduced axial flexibility and an increased tangential torsional rigidity of the respective portion of the tubular sheath.

43. The device of claim 42, wherein a further gradual closure of the slots opposing the locks results in a bending of the respective portion of the tubular sheath.

44. The device of claim 40, wherein a change in shape in response to an operator imposing a force to the control element to enable the operator to vary the length of the tubular sheath comprises a lengthening of the portion of the tubular sheath that defines the hinges, such lengthening causes a gradual opening of the opposing slots and a bending of the respective portion of the tubular sheath.

45. The device of claim 44, wherein a lengthening of the section comprising the locking members causes a closure of the gap around the locking members, resulting in an at least one of a reduced axial flexibility and increased tangential torsional rigidity of the respective portion of the tubular sheath.

46. The device of claim 45, wherein a further gradual widening of the slots opposing the locking members results in a bending of the section.

47. The device of claim 40, wherein the slot width around the interlocking members is smaller than on the circumferential opposing side where no interlocking members are present.

48. The device of claim 1, wherein a relative torsional displacement between adjacent loops in the helical wall of the tubular sheath is prevented by an additional rigidity element, comprising a polymer, glue or related material that fills the gaps and resists change of length and tangential shear between adjacent coils.

49. The device of claim 1, wherein an additional polymer sheath, applied on the outer surface of the helix prevents a relative torsional displacement between adjacent loops in the helical wall of the tubular sheath.

50. The device of claim 49, wherein the polymer sheath has a wall thickness that is larger on the convex side than on the concave side.

51. The device of claim 1, wherein an eccentric reinforcement element is attached to the helical sheath by a technique comprising dipping, extrusion, welding, crimping, brazing, gluing and embedding in a cover material that is surrounding the sheath.

52. The device of claim 1, further comprising at least one additional slot configured to provide additional flexibility and/or steerability by bending.

53. The device of claim 52, wherein two or more continuous helical slots are used to reduce the risk of failure.

54. The device of claim 52, wherein steerability by bending is achieved by additional short slots located at the concave side only, which run over an angle less than 360 degrees, between the slots of the main helix.