Flexible atraumatic sheath tip

Abstract

To provide, among others, apparatuses, systems and methods for providing an atraumatic sheath tip, where various disclosed embodiments seek to help reduce or avoid unnecessary tissue damage upon a sheath being extended to convey an elongated instrument for sampling or treatment.SOLUTION: In an illustrative embodiment, an apparatus includes a deformable sheath tip 205 configured to be positioned at a distal end 105 of a sheath 103. The sheath defines therein a lumen configured to convey an elongated instrument. The sheath tip has a base end disposable at the distal end of the sheath, and a contact end. The sheath tip has a first column strength along an axis of the sheath tip that is less than a second column strength of the sheath, and a first degree of deformability that is greater than a second degree of deformability of the sheath.SELECTED DRAWING: Figure 3B

Description

[Technical field]

[0001] The present disclosure relates to a sheath used to extend an extension instrument. [Background technology]

[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

[0003] The ability to access tissues within a patient's body without invasive surgery allows for ever-advancing types of analysis, diagnosis, and treatment with less pain, faster recovery time, and reduced risk of complications. As two examples, endoscopic and catheterization techniques have made it possible to evaluate and treat many internal injuries without invasive surgery.

[0004] For example, suspected or actual lesions may be sampled or treated by extending an elongated medical instrument, such as a sampling needle, through a sheath that is positioned by an insertion control system, such as a bronchoscope or endoscope. The sheath may be extended from the insertion control system to position the elongated medical instrument, and the elongated instrument itself may then be deployed for sampling or treatment.

[0005] While the use of an insertion control system avoids invasive surgery in some cases, it can bring its own challenges: For example, because the insertion control system may operate in tight spaces, it can be challenging to engage in sampling or treatment at a desired location within the body while attempting to minimize or avoid trauma to tissue at or near the desired location. Summary of the Invention [Problem to be solved by the invention]

[0006] The disclosed embodiments include devices, systems, and methods for providing an atraumatic sheath tip. It will be appreciated that the various disclosed embodiments seek to help reduce or avoid tissue damage when the sheath is extended to deliver an elongated instrument for sampling or treatment. [Means for solving the problem]

[0007] In an exemplary embodiment, the device includes a deformable sheath tip configured to be positioned at a distal end of a sheath. The sheath defines a lumen therein configured to carry an elongate instrument. The sheath tip has a disposable base end at the distal end of the sheath and a contact end. The sheath tip has a first column strength along an axis of the sheath tip that is less than a second column strength of the sheath and a first degree of deformation that is greater than a second degree of deformation of the sheath.

[0008] In another exemplary embodiment, a system includes a sheath defining a lumen therein. An elongated medical instrument is configured to be delivered through the lumen in the sheath. An insertion control system is configured to transport the sheath to a desired location within the body. An instrument control system is configured to direct movement of the elongated medical instrument when the elongated medical instrument reaches the desired location. A sheath tip is configured to be positioned at a distal end of the sheath. The sheath tip has a disposable base end at the distal end of the sheath and a contact end. The sheath tip has a first column strength along an axis of the sheath tip that is less than a second column strength of the sheath. The sheath tip has a first degree of deformation that is greater than a second degree of deformation of the sheath.

[0009] In a further exemplary embodiment, a method includes preparing an elongated instrument for delivery into a body through a lumen in a sheath, the sheath being extended toward tissue. The sheath includes a sheath tip configured to extend from a base end to a contact end at a distal end of the sheath, the sheath tip configured to be deformable, the sheath tip having a first column strength along an axis of the sheath tip that is less than a second column strength of a body of the sheath. The sheath carrying the elongated instrument is inserted into the body, the sheath tip deforming more easily than the body of the sheath when a force is applied to the contact end, such as may occur upon contact with tissue.

[0010] Further features, advantages and areas of application will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure.

[0011] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. The components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the disclosed embodiments. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a block diagram, in partial schematic form, of an exemplary system for sampling or treating tissue using an embodiment according to the present disclosure. [Diagram 2] FIG. 13 is a perspective view of a head on an insertion device including a sheath with an exemplary sheath tip attached. [Figure 3A] 3A-3C are side views of the head of the insertion device of FIG. 2 during preparation for sheath extension using an exemplary sheath tip, followed by sheath extension, respectively. [Figure 3B] 3A-3C are side views of the head of the insertion device of FIG. 2 during preparation for sheath extension using an exemplary sheath tip, followed by sheath extension, respectively. [Figure 4]1 is a cutaway view of an end of a sheath configured with an exemplary sheath tip. [Diagram 5] 1 is a cutaway view of an end of a sheath configured with an exemplary sheath tip. [Figure 6] 1 is a cutaway view of an end of a sheath configured with an exemplary sheath tip. [Figure 7A] FIG. 1 is a perspective view of an exemplary sheath tip in an undeformed state prior to contact with a surface. [Figure 8A] FIG. 1 is a perspective view of an exemplary sheath tip in an undeformed state prior to contact with a surface. [Figure 9A] FIG. 1 is a perspective view of an exemplary sheath tip in an undeformed state prior to contact with a surface. [Figure 10A] FIG. 1 is a perspective view of an exemplary sheath tip in an undeformed state prior to contact with a surface. [Figure 7B] FIG. 7B is a perspective view of the sheath tip of FIG. 7A in a deformed state after contacting a surface. [Figure 8B] FIG. 8B is a perspective view of the sheath tip of FIG. 8A in a deformed state after contacting a surface. [Figure 9B] FIG. 9B is a perspective view of the sheath tip of FIG. 9A in a deformed state after contacting a surface. [Figure 10B] FIG. 10B is a perspective view of the sheath tip of FIG. 10A in a deformed state after contacting a surface. [Figure 11] 13A-13C are side views of additional exemplary sheath tips. [Figure 12] 13A-13C are side views of additional exemplary sheath tips. [Figure 13] 13A-13C are side views of additional exemplary sheath tips. [Figure 14] 13A-13C are side views of additional exemplary sheath tips. [Figure 15] FIG. 1 is a flow diagram of an exemplary method of operating a device with a sheath tip. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It will be noted that the first digit of a three-digit reference number and the first two digits of a four-digit reference number correspond to the first digit of a one-digit figure number and the first two digits of a figure number, respectively, in which the element first appears.

[0014] The following description describes, by way of example only and not limitation, various embodiments of sheath tips, as well as systems including such sheath tips, and methods of using the sheath tips, that help reduce or attempt to prevent trauma when extending the sheath towards a surface. As described in more detail below, in various embodiments, the sheath tips are configured to deform upon contact with a surface to help reduce or attempt to avoid causing trauma to tissue at or near the point where the tissue is to be sampled or treated by an extension instrument carried by the sheath.

[0015] It will be appreciated that the various embodiments of the sheath tips described herein have compositions and structures that, in some embodiments, include various openings formed in the sheath tip to reduce the column strength of the sheath tip, allowing the sheath tip to deform when impacted against a surface, thereby potentially helping to avoid or reduce trauma to the surface.

[0016] With reference to FIG. 1, in various embodiments, an exemplary system 100 is provided for sampling or treating tissue at a reference point within an anatomical region of a patient (not shown in FIG. 1). In one example, the system 100 may include a sampling device having a vacuum system for drawing a sample through a sampling needle. Alternatively, the system 100 may be a bipolar radio frequency (RF) system for using an electric current to ablate or coagulate tissue within the patient, as desired. Further alternatively, the system 100 may include a mechanical or laser-based cutting system for cutting tissue within the patient. Any such system may involve inserting an elongated instrument into the patient to perform the desired procedure, and any such elongated instrument may be inserted into the patient through a sheath that may desirably terminate at a sheath tip, as disclosed herein.

[0017] In some embodiments, the system 100 includes an elongated medical instrument controllable by a user interface 101, one or more instrument control systems 114 and 116, an insertion control system 118, and various support devices. The user interface 101 may include a positioning device for positioning the distal end 105 of the sheath 103 relative to a location of interest within the body (not shown). The user interface 101 may also be configured to orient the position of the elongated instrument (not shown) housed within the sheath 103. The elongated instrument may include, for example, a sampling needle, one or more electrodes, an imaging device, a probe, a cutting device, or any other elongated device, as described below with reference to FIGS. 4-6. One or more control systems 114 and 116 may be coupled to the elongated instrument and may include devices for withdrawing fluid or tissue, providing electrical current, monitoring sensor data, or performing other functions.

[0018] The insertion control system 118 may include a bronchoscope, endoscope, or another insertion system configured to manipulate the insertion device 119, which may include a steering mechanism as well as light, ultrasound, or other sensors to monitor the path of the insertion device 119. The user interface 101 may be received within the insertion control system 118 at a port 148 for the insertion control system 118, allowing the insertion control system 118 to orient the insertion device 119 to deliver the distal end 105 of the sheath 103 to a desired location within the body where the user interface 101 may then be used to manipulate an associated elongation instrument to perform a desired function.

[0019] The system may represent any number of sampling or treatment systems. As an example, the system 100 may be a sampling system for taking tissue samples using a sampling needle, as described further below with reference to Figures 4-6. In such a case, the insertion control system 118 may include a bronchoscope if the sample is to be taken from the respiratory system, or an endoscope if the sample is to be taken from the digestive system. One instrument control system 114 may be used to receive and process the sensor data, and may be operated by the controls 120, 122, and 124. Another instrument control system 116 may be a pump or other vacuum source for drawing a tissue or fluid sample from a sampling needle, which may extend from the distal end 105 of the sheath 103.

[0020] In another example, system 100 may be a cutting system for cutting through tissue obstructions. In such a case, insertion control system 118 may include an endoscope for directing when samples are to be taken from the digestive system. One instrument control system 114 may be used to receive and process sensor data and may be operated by controls 120, 122, and 124. Another instrument control system 116 may be a cutting control system for moving a reciprocating and / or rotating cutting device extending from the distal end 105 of sheath 103.

[0021] In yet another example, the system 100 may be an electrosurgical radio frequency (RF) system for ablation, cauterization, or coagulation of tissue. In such a case, the insertion control system 118 may include a bronchoscope if the sample is to be taken from the respiratory system, or an endoscope if the sample is to be taken from the digestive system. One of the instrument control systems 114 may be a generator that operates as a switchable power source 114 to apply power to the elongated instrument extending from the distal end 105 of the sheath. The user interface 101 is in electrical communication with the switchable power source 114 through electrical conductors 130. In some embodiments, the electrical conductors 130 are connected to an outlet 131 when the system is operated in a bipolar mode. The electrical conductors 130 may be coupled to the outlet 131 using an electrical connector 134 configured to electrically engage the outlet 131. The switchable power source 114 may be operated by use of a foot-operated unit 120 electrically connected to the switchable power source 114. The foot-operated unit 120 may include a pedal 122 that instructs the switchable generator 114 to apply power to the electrode(s) (described below) to cut and / or ablate tissue, and a pedal 124 that instructs the generator 114 to apply a lesser amount of power to the electrode(s) to coagulate tissue.

[0022] The user interface 101 is further connected to the conductive fluid source 116 by a tube 132 that facilitates the flow of a liquid, such as saline or another conductive fluid, from the conductive fluid source 116 to the user interface 101. Another instrument control system 116 may be a conductive fluid source 116, such as an infusion pump controllable by a switch, to provide conductive fluid to the distal end 105 of the sheath 103, where the conductive fluid can be vaporized by applied power to generate heat for ablating or cauterizing tissue.

[0023] The system 100 may include any number of medical or non-medical systems in which an elongated instrument is extended through the sheath 103 to perform a procedure, and a sheath tip according to the present disclosure may be applied to the distal end 105 of the sheath 103 to facilitate such a procedure. The embodiments of the sheath tip of the present disclosure are not limited to use with any particular system or function. Any applications for use of the sheath tip of the present disclosure are provided by way of example only and should not be considered limiting.

[0024] 2, the head 201 of the insertion device 119 includes various sensor or associated devices 250, 252, and 254 that can be used to locate the distal end 105 (FIG. 1) of the sheath 103. For example, the head 201 may support an ultrasound transducer 250 that emits ultrasound energy and receives reflected ultrasound energy. The head 201 may also support a camera 254, which may be provided with a light source 246 for illuminating an area adjacent the head 201. The ultrasound transducer 250 and / or camera 254 may be used to identify a lesion or other area of ​​interest to be sampled or treated by an elongated instrument (not shown in FIG. 2) delivered through the sheath 103.

[0025] The distal end 105 of the sheath 103 defines a lumen 207 therein through which an elongate instrument (not shown in FIG. 2) may extend. The distal end 105 of the sheath may be fitted with a sheath tip 205 as described below.

[0026] 3A, the head 201 is disposed adjacent to a tissue surface 301, such as an interior surface of a body canal into which the head 201 may be inserted. The head 201 is in position for extension of the sheath 103 before the sheath 103 is extended. Upon deployment, the sheath 103 extends along an axis 303 that may potentially cause the sheath 103 to intersect a tissue wall. A protrusion 305, represented by a dashed line centered on the axis 303, shows how the sheath 103 may impinge on the tissue surface 301. A sheath tip 205 disposed at the distal end 105 of the sheath 103 may help reduce or avoid trauma to the tissue surface 301, as described below with reference to FIG. 3B.

[0027] 3B, after extension of the sheath 103, the sheath tip 205 deforms upon contact with the tissue surface 301. Instead of potentially deforming as the sheath 103 is extended along the axis 303 relative to the tissue surface 301 and potentially causing trauma to the tissue surface 301, the sheath tip 205 at least partially collapses, collapses, or otherwise deforms, potentially helping to avoid or minimize trauma to the tissue surface 301.

[0028] 4-6, the extension instrument 450 housed within the sheath 103 shows different configurations for containing the exemplary sheath tip 405, 505, or 605. The extension instrument 450 used in FIGS. 4-6 is a sampling needle configured to draw tissue samples from a tissue surface, lesion, or other body part, and includes an internal lumen 452 terminating at an open sampling end 454. The extension instrument 450 may be extended from the sheath 103 to collect a tissue sample (not shown) at the open sampling end 454, which is then drawn through the lumen 452 by a vacuum source for collection and testing. However, as detailed with reference to FIG. 1, the extension instrument 450 may include any of a number of instruments including electrodes, cutting devices, and other devices, and it should be understood that the sampling needle is used herein by way of example only and not limitation.

[0029] With reference to FIG. 4, the distal end 407 of the sheath 103 includes a sheath tip 405 that is integrally formed with the sheath 103. The sheath tip 405 may be molded, extruded, or otherwise formed as part of the sheath 103 when the sheath 103 is formed. The sheath tip 405 may include any number of features described below with reference to FIGS. 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14 to provide the sheath tip 405 with a desired deformability that helps to avoid or reduce potential tissue trauma as described with reference to FIGS. 3A and 3B. Cuts or other modifications to the sheath tip 405 may be made with a mechanical or laser cutter or other device after the sheath 103 and sheath tip 405 are molded or extruded. The sheath 103 and sheath tip 405 may be formed of plastic or any other flexible material.

[0030] An embodiment of the sheath 103 may be fitted with an insert 410 that is insertable or otherwise receivable within the sheath 103. The insert may serve the purpose of stiffening the sheath 103, except for the distal end 407, to aid in the extension of the sheath 103 through the insertion device 119 and head 201 (FIGS. 1-2 and 3A-3B). The insert 410 may also protect the sheath 103 from potential damage that may be caused by the extension tool 450, such as may be caused by a potentially sharp open sampling end 454 of the sampling needle, while the sheath 103 and / or the insertion device 119 are being manipulated to a desired location within the body (not shown). The sheath tip 405 may be formed beyond the end of the insert 410 or overlapping all or a portion of the insert 410, as described further below with reference to FIG. With the presence of a relatively rigid insert 410 within the sheath 103, the deformability of the sheath tip 405 can be particularly beneficial to potentially help reduce or avoid tissue trauma upon deployment of the sheath 103.

[0031] 5, in other embodiments, the sheath tip 505 is coupled to the sheath 103 at a distal end 507 of the sheath 103. In such embodiments, the sheath tip 505 may be molded, extruded, or otherwise formed separately from the sheath 103 when the sheath 103 is formed. The sheath tip 505 may be formed of plastic or any other suitable flexible material, and the sheath tip 505 may be joined to the distal end 507 of the sheath 103 by adhesive, heat welding, or any other technique operable to join the materials comprising the sheath 103 and the sheath tip 505 together. The sheath tip 505 may include any number of features described below with reference to Figures 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14 to provide the sheath tip 605 with a desired deformability that helps to avoid or reduce potential tissue trauma as described with reference to Figures 3A and 3B. Cuts or other modifications to the sheath tip 505 may be made with a mechanical or laser cutter or other device after molding or extrusion of the sheath tip 505. Cuts or other modifications may be made before or after the sheath tip 505 is joined to the distal end 507 of the sheath 103.

[0032] 6, in other embodiments, the sheath tip 605 is coupled to the sheath 103 at a distal end 607 of the sheath 103, where the distal end 607 of the sheath 103 overlaps the insert 410. In such embodiments, the sheath tip 605 may be molded, extruded, or otherwise formed separately from the sheath 103 when the sheath 103 is formed. The sheath tip 605 may be formed of plastic or any other suitable flexible material, and the sheath tip 605 may be joined to the distal end 507 of the sheath 103 by adhesive, heat welding, or any other technique operable to join together the materials comprising the sheath 103 and the sheath tip 605. The sheath tip 605 may be coupled to the insert 410 before or while the sheath tip 605 is joined to the sheath 103. Joining the distal end 607 of the sheath 103 and the sheath tip 605 at the point where it overlaps the insert may provide structural support to the joint where the sheath 103 and the sheath tip 605 are joined together. The sheath tip 605 may include any number of features described below with reference to FIGS. 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14 to provide the sheath tip 605 with a desired deformability that helps to avoid or reduce potential tissue trauma as described with reference to FIGS. 3A and 3B. Cuts or other modifications to the sheath tip 605 may be made with a mechanical or laser cutter or other device after molding or extrusion of the sheath tip 605. Cuts or other modifications may be made before or after the sheath tip 605 is joined to the distal end 607 of the sheath 103.

[0033] 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14 illustrate various embodiments of sheath tips configured to at least partially collapse, collapse, or otherwise deform upon extension of a sheath covered by the sheath tip extended toward and against a tissue wall as described with reference to 3A and 3B to help reduce trauma to, or avoid causing trauma to, tissue impinged by the sheath tip. In the embodiments of 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14, each of the sheath tips is configured to have a column strength along the axis of the sheath tip that is less than the column strength of the sheath. As a result, each of the sheath tips has a degree of deformation that is greater than the degree of deformation of the sheath. Reduced column strength can result from at least a portion of the sheath tip having a different wall thickness than the sheath, at least a portion of the sheath tip being made from a more deformable material than the sheath, or the sheath having a configuration that includes cuts or creases at the end or along its length that make the sheath tip more deformable, as described in the examples below.

[0034] With reference to Figures 7A-7B, 8A-8B, 9A-9B, and 10A-10B, it is noted that the surfaces 750 against which the sheath tips are oriented and against which they impinge are generally perpendicular to the axis of the sheath tips. However, it should be understood that the surfaces against which the sheath tips may impinge, and which they may desirably deform, may be either perpendicular to the axis of the sheath tips, as shown in Figures 7A-7B, 8A-8B, 9A-9B, and 10A-10B, or at an angle to the axis of the sheath tips, as previously described with reference to Figures 3A and 3B.

[0035] With reference to FIG. 7A, the sheath tip 705 has a base end 711 that is configured to be integral with, joined to, or otherwise disposed at the distal end of a sheath (not shown in FIG. 7A) as previously described with reference to FIGS. 3A and 3B and 4-6. The sheath tip extends from the base end 711 to a contact end 713 along an axis 755 of the sheath tip 705. The body 715 of the sheath tip 705 may be formed from a different material having a stiffness less than that of the sheath. Alternatively, or in addition, the sheath tip 705 may be of the same material as the sheath, but the sheath tip has a reduced thickness or thicknesses such that it is less stiff than the sheath. In either case, the sheath tip 705 is adapted to have a reduced column strength or stiffness compared to the sheath to provide a desired degree of deformation upon impact with the surface 750.

[0036] 7B, upon impact with surface 750, sheath tip 705 collapses or similarly deforms along the body 715 of sheath tip 705 between base end 711 and contact end 713. Thus, the collapse of the body 715 of sheath tip 705 absorbs the forces resulting from the impact of sheath tip 705 and surface 750. It should be understood that the deformation of sheath tip 705 is generally uniform along the body 715 of sheath tip 705. However, it should be understood that if sheath tip 705 is disposed at the end of a sheath such that it overlaps a sheath insert (not shown in FIGS. 7A and 7B), the portion of sheath tip 705 overlapping sheath insert 705 may not deform in the same manner as other portions of body 715 of sheath tip 705 between the contact end 713 and the overlapping portion of body 715.

[0037] 8A , in other embodiments, the sheath tip 805 includes a crumple zone 807 along the body 815 of the sheath tip 805 between the base end 811 and the contact end 813. In some embodiments, the crumple zone 807 has a non-deformed length 808 made of a material having a reduced thickness or reduced stiffness compared to the sheath to provide a desired degree of deformation upon impact with a surface 750, such as a tissue surface.

[0038] 8B, upon impact with surface 750, crumple zone 807 at least partially collapses as shown by crumple zone 807 deforming to a reduced length 809 to absorb a portion of the force due to contact end 813 impacting surface 750. In some embodiments, crumple zone 807 buckles outward (as shown in FIG. 8B) and / or inward around at least a portion of the circumference of sheath tip 805.

[0039] 9A , in another embodiment, the sheath tip 905 includes a longitudinal cut 917 around the periphery of the contact end 913 of the sheath tip 905. The longitudinal cut 917, which is generally parallel to the axis 955 of the sheath tip 905, provides a plurality of collapsible sections 919 around the periphery of the contact end 913 of the sheath tip 905.

[0040] 9B, upon impact with surface 750, sections 919 collapse between and / or around longitudinal breaks 917 to absorb some of the force due to contact ends 913 impacting surface 750. Sections 919 may buckle inwardly (as shown in FIG. 8B) and / or outwardly. In either case, it will be appreciated that longitudinal breaks 917 reduce the column strength of sheath tip 915 and allow deformation of sheath tip 905 relative to surface 750.

[0041] 10A, in another embodiment, the sheath tip 1005 includes an opening 1012 formed in the body 1015 of the sheath tip 1005 between the base end 1010 and the contact end 1013. The opening 1012 may be formed in the sheath tip 1005 during molding, or the opening 1012 may be cut into the sheath tip 1005 using a mechanical or laser cutting device. The opening 1012 may be oriented parallel to the axis 1055 of the sheath tip, perpendicular, or obliquely as shown in the embodiment of FIG. 10A. As shown in FIG. 10A, the opening 1012 is oblique and extends around the entire circumference of the sheath tip one or more times in a helical shape. The opening 1012 has a non-deformed width 1014 relative to the axis 1055 that results in a reduction in the column strength of the sheath 1005.

[0042] 10B, upon impact with surface 750, the sheath tip 1005 deforms around the opening 1012, causing the opening 1012 to collapse to a deformed width 1016 to absorb a portion of the force resulting from the contact end 1013 impacting surface 750. Although not shown in FIG. 10B, the opening 1012 may also allow twisting or other deformation of the body 1015 of the sheath tip 1005 around the opening 1012 to allow further deformation of the sheath tip 1005 and avoid trauma to the surface 750.

[0043] 11-14, the breaks or openings in the sheath tip can be configured in many different shapes to provide a desired reduction in stiffness and / or increased deformability compared to the sheath. The further examples in Figures 11-14 are provided by way of example only and not by way of limitation.

[0044] With reference to Figure 11, the sheath tip 1105 may include an opening 1112 that is oblique to the axis 1155 of the sheath tip 1105. However, unlike the opening 1012 of the sheath tip 1005 of Figure 10, the opening 1112 does not extend completely around the circumference of the sheath tip 1105. With reference to Figure 12, the sheath tip 1205 may include an opening 1212 that is perpendicular to the axis 1255 of the sheath tip 1205.

[0045] 13, the openings or discontinuities in the sheath tip 1305 may include radial ends that help provide the desired flexibility. The sheath tip 1305 includes openings 1312 that are generally perpendicular to the axis 1355 of the sheath tip 1305, as in the sheath tip 1205 of FIG. 12. However, each of the openings 1312 includes an elongated slot 1314 that terminates at a radial end point 1316, including, for example, a cylindrical or conical opening formed around the periphery of the end of the elongated slot 1314.

[0046] 14, instead of or in addition to an opening extending through the entire thickness of the sheath tip, the sheath tip may be molded or partially cut to form creases in the sheath tip to provide the desired deformability. The sheath tip 1405 includes a plurality of creases or partial cuts 1424 in the nature of accordion-type creases along the axis 1455 of the sheath tip 1405. The creases or partial cuts may be formed in the molding of the sheath tip 1405, or some material may be cut from the sheath tip 1405 with a mechanical or laser cutting device to form the creases or partial cuts 1424, which may be formed only on the outer surface of the sheath tip 1405, only on the inner surface of the sheath tip 1405, or on both the outer and inner surfaces of the sheath tip 1405. The differential thickness formed along the axis of the sheath tip 1405 reduces the column strength of the sheath tip 1405, resulting in reduced stiffness / greater deformability, which helps reduce the trauma that may be caused by the sheath tip 1405 upon impact with a surface.

[0047] It should be understood that combinations of the structures described herein may be used to create a sheath tip having a desired degree of deformation. For example, an oblique opening (FIG. 11) may be formed with a radial end point (FIG. 13). An opening formed along the body of the sheath tip (FIGS. 11-13) may be combined with a crease or partial cut along another portion of the body (FIG. 14). Additionally, a sheath tip having a crease or partial cut or opening along the body may be combined with a longitudinal cut at the contact end (FIGS. 9A-9B). Any of these structures may also be combined with a crumple zone (FIGS. 8A-8B). Similarly, the use of any of these structures may be combined with a sheath tip formed of a different material or material having a different thickness than the sheath (FIGS. 7A-7B). Any such combination may be used to provide a sheath tip having a desired degree of deformation. The above structures and / or combinations are provided by way of example and not limitation in forming a sheath body having a desired degree of deformation.

[0048] With reference to FIG. 15, an exemplary method 1500 of using a sheath tip in deploying an elongated instrument through a sheath is provided. The method 1500 begins at block 1505. At block 1510, an elongated instrument is prepared for delivery into the body through a lumen in a sheath, the sheath being extended toward tissue. The sheath includes a sheath tip configured to extend from a base end to a contact end at a distal end of the sheath, the sheath tip configured to be deformable, the sheath tip having a first column strength along an axis of the sheath tip that is less than a second column strength of a body of the sheath. Such a sheath tip configuration is described with reference to FIGS. 3A-3B, 4-6, 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14.

[0049] At block 1520, a sheath carrying an elongated instrument is inserted into the body, the sheath tip deforming more easily than the body of the sheath when force is applied to the contact end, such as may occur upon contact with tissue. Insertion of the elongated instrument is described with reference to Figures 1-2 and 3A-3B. Deformation of the sheath tip is described with reference to Figures 3B, 4-6, 7A-7B, 8A-8B, 9A-9B, 10A-10B, and 11-14. Method 1500 ends at block 1525.

[0050] It will be understood that this description of a sheath tip for use in the insertion of an elongate instrument into the body through a sheath is not limited to either the type of elongate instrument described or to use with a medical instrument in vivo, A sheath tip of the nature as described may be used in any application where a lumen may contact a surface where damage may result from impaction of the lumen against the surface.

[0051] It will also be understood that the detailed description set forth above is merely exemplary in nature and that variations that do not depart from the spirit and / or scope of the claimed subject matter are intended to be within the scope of the claims. Such variations are not to be regarded as a departure from the spirit and scope of the claimed subject matter. [Explanation of symbols]

[0052] 100 Systems 101 User Interface 103 Sheath 105 Distal end 114 Instrument control systems / power supplies / generators 116 Instrument Control System / Conductive Fluid Source 118 Insertion Control System 119 Insertion Device 120 Control / Foot-operated unit 122 Controls / Pedals 124 Pedals 130 Conductors 131 Exit 132 tube 134 Electrical Connectors 148 Port 201 Head 205 Sheath tip 207 Lumen 246 Light source 250 Related Devices / Ultrasonic Transducers 252 Related Devices 254 Camera 301 Tissue surface 303 Axis 305 Protrusion 405 Sheath tip 407 Distal end 410 Insert 450 Extension device 452 Internal lumen 454 Open Sampling End 505 Sheath tip 507 Distal end 605 Sheath tip 607 Distal end 705 Sheath tip / Sheath insert 711 Base end 713 Contact end 715 Main unit 750 surface 755 Axis 805 Sheath tip 807 Crumple Zone 811 Base end 813 Contact end 815 Main Unit 905 Sheath tip 913 Contact end 915 Sheath tip 917 Break Section 919 955 Axis 1005 Sheath tip 1010 Base end 1012 Opening 1013 Contact end 1014 Undeformed width 1015 Main unit 1016 Deformation width 1055 Axis 1105 Sheath tip 1112 Opening 1155 Axis 1205 Sheath tip 1212 Opening 1255 Axis 1305 Sheath tip 1312 Opening 1314 Extension Slot 1316 Radial End Point 1355 Axis 1405 Sheath tip 1424 Break 1455 Axis 1500 ways

Claims

1. 1. An apparatus comprising: a deformable sheath tip configured to be positioned at a distal end of a sheath defining a lumen therein configured to carry an elongate instrument, the sheath tip having a base end at the distal end of the sheath and a contact end, the sheath tip having a first column strength along an axis of the sheath tip that is less than a second column strength of the sheath, the sheath tip having a first degree of deformation that is greater than a second degree of deformation of the sheath, the sheath having a common outer diameter with the sheath tip; the sheath tip is configured to be physically coupled to the distal end of the sheath in a sheath insert configured to be received within the lumen of the sheath; the sheath has a third column strength at the location of the sheath insert; The third column strength is greater than the second column strength.

2. The device of claim 1 , wherein the sheath tip is integrally formed with the sheath, the sheath tip being disposed at the distal end of the sheath.

3. The device of claim 1 , wherein the sheath tip is a separate structure configured to be attached to the distal end of the sheath.

4. 10. The device of claim 1, wherein the sheath tip has at least one characteristic selected from a first thickness less than a second thickness of the sheath and a first stiffness less than a second stiffness of the sheath.

5. 2. The device of claim 1, wherein the sheath tip includes at least one crumple zone along a circumferential periphery of the sheath tip between the base end and the contact end, the crumple zone being collapsible in response to application of a force to the contact end.

6. 2. The device of claim 1, wherein the sheath tip defines a plurality of longitudinal cuts therein about a periphery of the contact end, the plurality of longitudinal cuts being configured to allow sections of the sheath tip to collapse about the plurality of longitudinal cuts in response to application of a force to the contact end.

7. The device of claim 1 , wherein the sheath tip defines a plurality of gaps along the length of the sheath tip between the base end and the contact end.

8. The apparatus of claim 7 , wherein each of the plurality of voids is defined intermediate the base end and the contact end.

9. The apparatus of claim 7 , wherein the plurality of voids includes at least one oblique opening along a length of the sheath tip, the oblique opening being defined relative to the axis of the sheath tip.

10. The device of claim 9 , wherein at least one of the plurality of angled openings at least completely circumnavigates the sheath tip.

11. The device of claim 7 , wherein each of the plurality of voids is generally perpendicular to the axis of the sheath tip.

12. The apparatus of claim 7 , wherein the plurality of voids comprises a plurality of elongated slots.

13. The apparatus of claim 12 , wherein at least one of the plurality of elongated slots terminates in at least one end selected from a cylindrical end and a conical end.

14. The device of claim 1 , wherein the sheath tip has a different thickness between the base end and the contact end.

15. 2. The device of claim 1, wherein the sheath tip includes a plurality of accordion-shaped contours on at least one of an inner surface and an outer surface of the sheath tip, the plurality of accordion-shaped contours being generally perpendicular to the axis of the sheath tip.

16. 1. A system comprising: a sheath defining a lumen therein; an elongate medical instrument configured to be delivered through the lumen within the sheath; an insertion control system configured to deliver the sheath to a desired location within a body; an instrument control system configured to direct the movement of the elongated medical instrument when the elongated medical instrument reaches a desired position; A deformable sheath tip configured to be positioned at a distal end of a sheath defining a lumen therein configured to carry an elongate instrument, the sheath tip having a disposable base end at the distal end of the sheath and a contact end, the sheath tip having a first column strength along an axis of the sheath tip that is less than a second column strength of the sheath, the sheath tip having a first degree of deformation greater than a second degree of deformation of the sheath, the sheath having a common outer diameter with the sheath tip, and the sheath tip having a disposable base end at the distal end of the sheath and a contact end. a deformable sheath tip configured to be physically coupled to the distal end of the sheath at a sheath insert configured to be received within the lumen, the sheath having a third column strength at the sheath insert location, the third column strength being greater than the second column strength, the elongated medical device being an elongated tissue piercing device, and the insertion control system including an exit port on a side of an insertion device configured to direct the sheath toward tissue to be sampled.

17. The system of claim 16 , wherein the insertion control system comprises a bronchoscope.

18. The system of claim 16 , wherein the elongate medical instrument comprises a sampling needle.

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