Expandable transluminal sheath

• US 20060052750A1
• Filed: 08/08/2005
• Published: 03/09/2006
• Est. Priority Date: 09/09/2004
• Status: Active Grant

• Current Assignee: Terumo Medical Corporation (Terumo Corporation)
• Original Assignee: Onset Medical Corp. (Terumo Corporation)
• Inventors: Bishop, Joseph, Kick, George F., Nance, Edward J., Lenker, Jay
• Granted Patent: US 7,892,203 B2
• Time in Patent Office: Days
• US Class Current: 604/164.10
• CPC Class Codes: A61B 17/0218 for minimally invasive surgery A61B17/0281, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/22 Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for dilators A61M29/00
• CPC Class Codes: A61B 17/22031 Gripping instruments, e.g. forceps, for removing or smashing calculi A61B17/221 takes precedence
• CPC Class Codes: A61B 17/3439 with means for changing the inner diameter of the cannula, e.g. expandable A61B17/3423, A61B17/3431 take precedence; catheters A61M25/0662
• CPC Class Codes: A61B 2017/0225 flexible, e.g. fabrics, meshes, or membranes
• CPC Class Codes: A61M 2025/0024 Expandable catheters or sheaths
• CPC Class Codes: A61M 2025/0681 Systems with catheter and outer tubing, e.g. sheath, sleeve or guide tube
• CPC Class Codes: A61M 2025/1081 having sheaths or the like for covering the balloon but not forming a permanent part of the balloon, e.g. retractable, dissolvable or tearable sheaths
• CPC Class Codes: A61M 25/0017 specially adapted for long-term hygiene care, e.g. urethral or indwelling catheters to prevent infections
• CPC Class Codes: A61M 25/0662 Guide tubes
• CPC Class Codes: A61M 27/008 pre-shaped, for use in the urethral or ureteral tract

Abstract

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The distal end of the sheath is maintained in the first, low cross-sectional configuration and expanded using a radial dilatation device. In an exemplary application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as ureteroscopy or stone removal.

Claims

1. An expandable transluminal access sheath adapted for providing minimally invasive access to body lumens or cavities, comprising:

an axially elongate sheath tube with a proximal and a distal end and a central through lumen;

a distal region of the sheath which is expandable in circumference in response to pressure applied therein,

a hub affixed to the proximal end of the sheath tube, the hub adapted to form a tapered internal lumen to facilitate the passage of instrumentation;

a central obturator, which serves to occlude the central lumen of the sheath during insertion; and

a guidewire lumen within the obturator, capable of passing standard medical guidewires;

wherein the obturator is a balloon dilator capable of expanding the distal region of the sheath.

2. The transluminal sheath of claim 1 wherein the sheath tube comprises an outer layer, an inner layer, and a reinforcing layer wherein the outer layer and the inner layer comprises a polymer.

7. The transluminal sheath of claim 2 wherein the sheath bends predominantly by plastic deformation rather than elastic deformation.

8. The transluminal sheath of claim 2 wherein the sheath bends predominantly by plastic deformation, said deformation being enhanced by subjecting the sheath to temperatures substantially near those of body temperature.

9. The transluminal sheath of claim 2 wherein the reinforcing layer is a braided structure fabricated from polymeric materials.

16. The transluminal sheath of claim 2 wherein the reinforcing layer is substantially deformable in cross-section.

17. The transluminal sheath of claim 2 wherein the sheath tube is substantially deformable in cross-section in response to irregularly shaped objects being advanced or withdrawn therethrough.

20. The transluminal sheath of claim 2 wherein the sheath comprises a radiopaque marker.

33. The transluminal sheath of claim 1 wherein the balloon dilator comprises a central guidewire lumen.

34. The obturator of claim 1 further comprising a tapered tip further comprising multiple tapers and diameters.

35. The obturator of claim 1 comprising a tapered tip which is substantially cylindrical at the distal end, tapering up to a larger cylinder at its proximal end.

36. The obturator of claim 1 wherein a distal end of a tapered tip is capable of tracking over a 0.035 to 0.038-inch diameter guidewire around corners as tight as 1.5-cm radius.

37. The obturator of claim 1 wherein the distal tip of the dilator is no larger than 4.5 French in diameter.

38. The obturator of claim 1 wherein the outer surface of said obturator comprises longitudinally oriented ridges and adjacent valleys, the purpose of the ridges and valleys being to minimize friction between the obturator and the inner surface of the sheath.

39. The sheath of claim 1 further comprising a cap hub on the obturator that securely and reversibly fastens to the hub on the sheath and locks in two substantially orthogonal axes.

42. The sheath of claim 1 wherein the inner surface of the sheath comprises longitudinally running ridges and adjacent valleys.

43. The sheath of claim 2 wherein the inner surface of the inner layer of the sheath comprises longitudinally running flutes for reducing friction between the inner layer and instrumentation or material being advanced or withdrawn therethrough.

44. The sheath of claim 2 wherein the inner surface of the inner layer is dimpled to enhance liquid surface coating of said liner.

45. The sheath of claim 2 wherein the outer surface of the outer layer comprises longitudinally oriented ridges and adjacent valleys, the purpose of which is to enhance liquid transmission along the outer surface of said sheath.

46. The sheath of claim 1 further comprising an atraumatic tip.

47. The sheath of claim 1 further comprising a sheath tube tip fabricated from materials softer than those used on the sheath tube.

59. The sheath of claim 2 comprising a coil reinforcement, wherein the coil is welded or fused to itself at the distal end of the sheath so as to form a ring structure.

60. The sheath of claim 2 comprising a coil reinforcement, wherein the coil is wound onto the inner layer of the sheath with substantially neutral spring tension.

61. The sheath of claim 1 wherein a proximal region of the sheath tube is non-expandable.

3-6. -6. (canceled)

10-15. -15. (canceled)

18-19. -19. (canceled)

21-32. -32. (canceled)

40-41. -41. (canceled)

48-58. -58. (canceled)

62-63. -63. (canceled)

64. A method of instrumenting a body lumen or cavity comprising the steps of:

inserting a sheath with a pre-inserted dilator, and advancing the sheath to a treatment or diagnostic site within the body lumen or cavity, wherein the sheath comprises a distal region which is collapsed in diameter,

dilating the distal region of the sheath so that the distal region of the sheath is expanded, wherein a full-size lumen exists within the sheath and extending from the proximal end to the distal end,

collapsing the dilator by an action applied at the proximal end of said dilator,

removing the dilator from the sheath,

inserting instrumentation through the lumen of the sheath,

performing therapy or diagnosis with the instrumentation, and

removing the sheath from the patient.

65. The method of claim 64 wherein the dilation step is performed by inflating a balloon on the dilator.

66. The method of claim 64 wherein the dilation step is performed by attaching a liquid-filled inflation device to a balloon inflation port at the distal end of the dilator and infusing liquid under pressure into the dilator.

67. The method of claim 64 wherein the step of collapsing the dilator comprises withdrawing a plunger on the inflation device to withdraw liquid from the dilator.

68. The method of claim 64 wherein a guidewire is advanced to the treatment site prior to inserting the sheath and dilator into the body lumen or cavity.

69. The method of claim 64 wherein the sheath is advanced over a previously placed guidewire, which is routed through a lumen in the dilator.

70. The method of claim 64 wherein the sheath is advanced to a point in the body lumen or cavity which is anatomically distal to the site where therapy or diagnosis will be carried out by the instrumentation.

71-74. -74. (canceled)

75. A sheath adapted for insertion into a body lumen or cavity comprising:

a means for tracking over a guidewire to a target treatment site,

a means for traversing into a small body lumen, wherein the sheath is diametrically collapsed along at least a portion of its distal length,

a means for dilating the distal end of the sheath, wherein the dilating means is operable from the proximal end of the sheath, and

a means for removal of the sheath from the patient body lumen or cavity.

76-78. -78. (canceled)

79. An axially elongate sheath device comprising a non-expandable proximal end and an expandable distal end, adapted for providing therapeutic or diagnostic access to a kidney or ureter wherein the distal end has an outer diameter of less than 10 French that can be subsequently dilated to a diameter of 12 French or larger and maintaining said dilated size.

80. The device of claim 79 comprising a proximal end that is pushable, and torqueable.

81. The device of claim 79 comprising external surfaces that posses the characteristics of low friction with urethra and ureter.

82. The device of claim 79 further comprising a distal end capable of bending through tortuosity and radii less than 2.0 cm before and after expansion.

83. The device of claim 79 further comprising a through lumen that is substantially the same size from proximal opening to distal opening of the catheter, following expansion of the expandable distal end.

84. The device of claim 79 further comprising a length capable of reaching the pelvis of the kidney, said length being between 25 and 55 cm.

85. The device of claim 79 further comprising a dilatable length between 10 and 45 cm.

86. The device of claim 79 further comprising a distal expandable region capable of expanding and substantially maintaining its shape at internal dilator pressures of between 4 atmospheres and 20 atmospheres, and preferably between 5 atmospheres and 15 atmospheres.

87. The device of claim 79 further comprising a step transition at or near the distal end of the axially elongate structure, said step transition being smoothed by a fairing.

88. The device of claim 79 further comprising a non-symmetrical step transition at or near the distal end of the axially elongate structure, said step transition being smoothed by a fairing.

89. The device of claim 79 further comprising a balloon to dilate the distal end of the sheath, a fairing to smooth the transition between the distal end of the balloon and the distal end of the sheath, wherein said fairing comprises an enlargement disposed under the balloon and outside a shaft upon which the balloon is carried.

90. The device of claim 79 further comprising a balloon to dilate the distal end of the sheath, a fairing to smooth the transition between the distal end of the balloon and the distal end of the sheath, wherein said fairing comprises an enlargement under the distal end of the balloon, said enlargement having been created by injecting a liquid under said balloon and having said liquid set-up to form a structure with mechanical integrity.

91-96. -96. (canceled)

97. A transluminal access sheath adapted for insertion into a urethra by a person having a pair of adjacent fingers, the access sheath comprising:

an elongate tube having a lumen extending between a proximal end and a distal end, wherein a distal portion of the elongate tube is expandable from a first, smaller diameter to a second, greater diameter

a proximal portion of the elongate tube which is substantially non-expandable and which is affixed at its distal end to the proximal end of the expandable distal portion;

a removable dilator disposed within the lumen of the transluminal access sheath, wherein the dilator is used to expand the distal portion of the access sheath;

a hub affixed to the proximal end of the elongate tube;

portions of the hub defining a distally facing surface and a proximally facing surface, the distally facing surface being concave, sized and configured to receive adjacent fingers of the user, the proximally facing surface being convex an configured to funnel instrumentation into the lumen;

a malleable reinforcement embedded within at least the distal expandable portion of the elongate tube; and

a polymeric material, from which the elongate tube is fabricated and, in which the malleable reinforcement is embedded.

98. The transluminal sheath of claim 97 wherein the sheath hub is configured at its distal end to slip into the urethra and to allow the proximal end of the sheath tube to slip into the urethra.

99. The transluminal sheath of claim 97 wherein the sheath hub is configured with a substantially linear outline when viewed in axial cross-section

100. The transluminal sheath of claim 97 wherein the sheath hub diameter is less than ½

the diameter of a finger, the shape of the distally facing side of the hub is not curved to a radius substantially the same as a finger, and wherein the hub is not receivable by adjacent fingers.

101. The transluminal sheath of claim 97 wherein the proximally facing side of the sheath hub is releasably affixed to a dilator hub, which covers the proximally facing side of the sheath hub, wherein the dilator hub further comprises a dilator inflation port and a guidewire lumen.