Sheath tip with angled distal face

Disclosed embodiments include apparatuses, systems, and methods for providing a sheath tip with an angled distal face to conform the sheath to a surface of tissue toward which the sheath is being extended to potentially help reduce or avoid tissue damage upon extending a sheath to convey an elongated instrument for sampling or treatment. In an illustrative embodiment, an apparatus includes a sheath tip configured to be positioned at an end of a sheath that is extendable toward a tissue at an angle to a surface of the tissue. The sheath tip has a distal end that is angled such that a periphery of the sheath tip at the distal end is configured to generally conform to the surface of the tissue.

FIELD

The present disclosure relates to a sheath used to extend an elongated instrument.

BACKGROUND

The ability to access tissue within a patient's body without invasive surgery allows for ever-improving types of analysis, diagnosis, and treatment with reduced pain, reduced recovery time, and a reduced risk of complications. By way of two examples, endoscopic and catherization techniques have enabled evaluation and treatment of numerous internal lesions without invasive surgery.

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 an endoscope. The sheath may be extended from the insertion control system to position the elongated medical instrument, then the elongated instrument itself may be deployed for sampling or treatment.

Use of the insertion control system, while possibly avoiding invasive surgery, may pose its own challenges. For example, because the insertion control system may operate in tight spaces, it may be a challenge to engage in sampling or treatment at a desired position within in a body while minimizing or attempting to avoid or minimize trauma to the tissue at or near the desired position or other undesirable effects resulting from contact between the insertion control system and tissue walls.

SUMMARY

Disclosed embodiments include apparatuses, systems, and methods for providing a sheath tip with an angled distal face to conform the sheath to a surface of tissue toward which the sheath is being extended. It will be appreciated that various disclosed embodiments seek to help reduce or avoid tissue damage upon a sheath being extended to convey an elongated instrument for sampling or treatment or other undesirable effects resulting from the sheath pushing against tissue surfaces.

In an illustrative embodiment, an apparatus includes a sheath tip configured to be positioned at an end of a sheath that is extendable toward a tissue at an angle to a surface of the tissue. The sheath tip has a distal end that is angled such that a periphery of the sheath tip at the distal end is configured to generally conform to the surface of the tissue.

In another illustrative embodiment, a system includes a sheath defining therein a lumen and that is configured to be extendable toward a tissue at an angle to a surface of the tissue. An elongated medical instrument is configured to be delivered through the lumen in the sheath. An insertion control system is configured to convey the sheath to a desired location within a body. An instrument control system is configured to direct operation of the elongated medial instrument when the elongated medical instrument reaches a desired position. A sheath tip is configured to be positioned at an end of the sheath. The sheath tip has a distal end that is angled such that a periphery of the sheath tip at the distal end is configured to generally conform to the surface of the tissue.

In a further illustrative embodiment, a method includes preparing an elongated instrument for being conveyed into a body through a lumen in a sheath. The sheath is to be extended toward a tissue at an angle to a surface of the tissue. The sheath includes a sheath tip at a distal end of the sheath, with a distal end of the sheath tip being angled such that a periphery of the sheath tip at the distal end is configured to generally conform to the surface of the tissue. The sheath conveying the elongated instrument into the body is inserted into the body.

DETAILED DESCRIPTION

The following description is merely illustrative in nature and is not intended to limit the present disclosure, application, or uses. It will be noted that the first digit of the three-digit reference numbers corresponds to the number of the figure in which the element first appears.

The following description explains, by way of illustration only and not of limitation, various embodiments of sheath tips to help reduce or seek to prevent undesirable effects resulting from extension of a sheath toward a surface, as well as systems including such sheath tips and methods of using the same. As will be described in detail below, in various illustrative embodiments the sheath tips are configured to have a shape that generally conforms to a tissue surface toward which the sheath tip is extended, thereby potentially helping to avoid or lessen displacement of instruments from tissue walls or trauma to the tissue surface.

Referring toFIG.1, in various embodiments, an illustrative system100is provided for sampling or treating tissue at a reference point in an anatomical region of a patient (not shown inFIG.1). For one example, the system100may include a sampling device with a vacuum system for drawing a sample via a sampling needle. Alternatively, the system100may be a bipolar radio frequency (RF) system, as desired, for using electrical current to ablate or coagulate tissue in a patient. Further alternatively, the system100may include a mechanical or laser-based cutting system for incising tissue in a patient. Any such system may involve insertion of an elongated instrument into a patient to perform a desired procedure, and any such elongated instrument may be inserted into a patient via a sheath which may desirably end in a sheath tip as disclosed herein.

In some embodiments, the system100includes an elongated medical instrument controllable by a user interface101, one or more instrument control systems114and116, an insertion control system118, and various supporting apparatuses. The user interface101may include a positioning device for positioning a distal end113of a sheath103relative to a position of interest in a body (not shown). The user interface101also may be configured to direct a position of an elongated instrument (not shown) that is housed within the sheath103. The elongated instrument, for example, may include a sampling needle, as described below with reference toFIGS.4-6, one or more electrodes, an imaging device, a probe, a cutting device, or any other elongated device. The one or more control systems114and116may be coupled to the elongated instrument and include devices to draw fluid or tissue, provide electrical current, provide fluid, monitor sensor data, or to perform other functions.

The insertion control system118may include a bronchoscope, an endoscope, or another insertion system configured to maneuver an insertion device119that may be equipped with a steering mechanism as well as optical, ultrasound, or other sensors to monitor the course of the insertion device119. The user interface101may be received into the insertion control system118so that the insertion control system118at a port148for the insertion control system118so that the insertion control system118may direct the insertion device119to convey the distal end113of the sheath103to a desired location in a body where the user interface101then may be used to manipulate an associated elongated instrument to perform a desired function.

The system may represent any number of sampling or treatment systems. For one example, the system100may be a sampling system to collect a tissue sample using a sampling needle, such as described further below with reference toFIGS.4-6. In such case, the insertion control system118may include a bronchoscope if the sample is to be collected from a respiratory system or an endoscope if the sample is to be collected from a digestive system. One instrument control system114may be used to receive and process sensor data and be operated by controls120,122, and124. Another instrument control system116may be a pump or other vacuum source to draw a tissue or fluid sample from the sampling needle that may extend from the distal end113of the sheath103.

For another example, the system100may be a cutting system for cutting through a tissue obstruction. In such case, the insertion control system118may include an endoscope to direct the if the sample is to be collected from a digestive system. One instrument control system114may be used to receive and process sensor data and be operated by controls120,122, and124. Another instrument control system116may be a cutting control system to motivate a reciprocating and/or rotating cutting apparatus extending from the distal end113of the sheath103.

For still another example, the system100may be an electrosurgical radio frequency (RF) system for ablating, cauterizing, or coagulating tissue. In such case, the insertion control system118may include a bronchoscope if the sample is to be collected from a respiratory system or an endoscope if the sample is to be collected from a digestive system. One instrument control system114may be a generator operating as a switchable power source114to apply electrical power to an elongated instrument extending from the distal end113of the sheath. The user interface101electrically communicates with the switchable power source114though an electrical conductor130. In some embodiments, the electrical conductor130is connected to an outlet131when the system is operated in a bipolar mode. The electrical conductor130may be coupled with the outlet131using an electrical connector134configured to electrically engage the outlet131. The switchable power source114can be operated with the use of a foot operated unit120electrically connected to the switchable power source114. The foot operated unit120may include, for example, a pedal122that instructs the switchable power source114to apply electrical power to electrode(s) (described below) to cut and/or ablate tissue and a pedal124that instructs the generator114to apply a lower quantity of electrical power to the electrode(s) to coagulate tissue.

The user interface101is further connected to the conductive fluid source116with a tube132that facilitates the flow of liquid, for example saline solution or another conductive fluid, from the conductive fluid source116to the user interface101. Another instrument control system116may be a conductive fluid source116, such as an infusion pump controllable by a switch, to provide a conductive fluid to the distal end113of the sheath103, where the conductive fluid may be vaporized by applied electrical power to generate heat to ablate or cauterize tissue.

The system100may include any number of medical systems or non-medical systems in which an elongated instrument is extended via a sheath103to perform an operation, and sheath tips in accordance with the present disclosure may be applied to the distal end113of the sheath103to facilitate such operations. Embodiments of the sheath tips of the present disclosure are not limited to use with any particular systems or functions. Any applications for use of the sheath tips of the present disclosure are provided solely for illustration and should not be taken as limiting.

Referring toFIG.2, a head201of the insertion device119includes various sensor devices or related devices250,254, and256usable in positioning the distal end113of the sheath103(FIG.1). For example, the head201may support an ultrasound transducer250that emits ultrasound energy and receives reflected ultrasound energy. The head201also may support a camera254, for which a light source256may be provided to illuminate a region adjacent the head201. The ultrasound transducer250and/or the camera254may be used to identify lesions or other regions of interest to be sampled or treated by an elongated instrument (not shown inFIG.2) to be conveyed through the sheath103.

The distal end113of the sheath103defines therein a lumen207from which the elongated instrument (not shown inFIG.2) may extend. The distal end113of the sheath may be fitted with an embodiment of an angled sheath tip205. Specifically, the angled sheath tip205has an angled distal face that is shaped around a periphery209of the angled sheath tip205so as to generally conform to the surface of a tissue to which the sheath103is to be extended, as further described below.

Referring toFIG.3A, the head201is disposed adjacent a tissue surface301, such as an interior surface of a bodily tract into which the head201may be inserted. The head201is in position for extension of the sheath103before the sheath103is extended. When deployed, the sheath103will extend along an axis303. However, the angled sheath tip205disposed at the distal end113of the sheath103may help reduce or avoid unnecessary or unwanted impact between the sheath103and the tissue surface301as described below with reference toFIG.3B.

Referring toFIG.3B, after extending the sheath103, the angled sheath tip205generally conforms to the tissue surface301. Without the angled sheath tip205, the sheath103may potentially intersect the tissue wall301. A projection355represented by a dashed line about the axis303shows that extending the sheath103without the angled sheath tip205potentially might have impinged upon the tissue surface301. Extending the sheath103without the angled sheath tip205may have undesirable effects. For one example, the extension of the sheath103against the tissue wall301may displace the head201from the tissue wall301, moving the tissue wall301away a relative distance357to a new wall location represented by dotted line359. (It will be appreciated that the relative displacement of the head201from the tissue wall301may be as a result of movement of the head201away from the tissue wall301, movement of the tissue wall301from the head201, or some combination of movement of the head201and the tissue wall301.) Such displacement may, therefore, displace the ultrasound transducer250from the tissue wall301and impair the ability of the ultrasound transducer250to scan tissues at or behind the tissue wall301. For another example, extension of the sheath103without the angled sheath tip205may distend or traumatize tissue at the tissue wall301. Instead of the sheath103potentially displacing, distending, or traumatizing the tissue surface301upon being extended along the axis303against the tissue surface301, the angled sheath tip205is shaped to generally conform to the tissue surface301to prevent potential undesirable effects from extension of the sheath103.

FIGS.4and5show different illustrative angled sheath tips405and505. Referring toFIG.4, an elongated instrument450is housed in a sheath403. The elongated instrument450is a sampling needle configured to draw a tissue sample from a tissue surface, lesion, or other body, and it includes an interior lumen452that terminates in an open sampling end454. The elongated instrument450may be extended from the sheath403to collect a sample of tissue (not shown) at the open sampling end454that is then drawn through the lumen452by a vacuum source for collection and testing. As described in detail with reference toFIG.1, however, it should be understood that the elongated instrument450may include any of a number of instruments including electrodes, cutting devices, other apparatuses, and the sampling needle shown is used here only by way of illustration and not limitation.

The angled sheath tip405ofFIG.4is integrally formed with the sheath403at a distal end413of the sheath403. The angled sheath tip405may be molded, extruded, or otherwise formed as part of the sheath403when the sheath403is formed. The angled sheath tip405also may be formed by cutting away a portion of the sheath403at the distal end413to form the angled sheath tip405The sheath403and the angled sheath tip405may be formed of plastic or any other flexible material. The angled sheath tip405has an angled distal end425, as previously described, so as to generally conform with a surface toward which the sheath403and the angled sheath tip405are extended.

In addition, the sheath403may be fitted with an insert410that is insertable or otherwise receivable within the sheath403. The insert may serve the purpose of stiffening the sheath403short of the distal end413for purposes of assisting extension of the sheath403through the insertion device119and the head201(FIGS.1,2,3A, and3B). The insert410also may protect the sheath403from potential damage that may be caused by the elongated instrument450, such as might be caused by a potentially sharp open sampling end454of a sampling needle while the sheath403and/or the insertion device119are maneuvered to a desired location within a body (not shown). The insert410may be received within the distal end413of the sheath403just inside the angled sheath tip405. As shown inFIG.4, the insert410may have an angled distal end423such that the angled distal end423of the insert410is generally parallel with the angled distal end425of the angled sheath tip405.

Referring toFIG.5, a separately formed angled sheath tip505is joined to a distal end513of a sheath503. In such embodiments, the angled sheath tip505may be molded, extruded, or otherwise separately formed from the sheath503. The angled sheath tip505may be formed of plastic or any other suitable flexible material. The angled sheath tip505may be joined to the distal end513of the sheath503by adhesives, heat welding, or any other technique that is operable to join together the materials that comprise the sheath503and the angled sheath tip505.

Also, and comparable to the illustrative embodiment ofFIG.4, the sheath503may be fitted with an insert510that is insertable or otherwise receivable within the sheath503. The insert may serve the purpose of stiffening the sheath503short of the distal end513for purposes of assisting extension of the sheath503through the insertion device119or protecting the sheath503from potential damage that may be caused by the elongated instrument450, as described with reference toFIG.4. The elongated instrument450, in the form of a sampling needle, is shown inFIG.5by way of illustration and not limitation, as inFIG.4. The insert510may be received at the distal end513of the sheath503. A distal end523of the insert may not be angled like a distal end525of the angled sheath tip505. Instead, the distal end523of the insert510may be generally parallel with the distal end513of the sheath503. The insert510may be situated where the angled sheath tip505meets the distal end513of the sheath503, potentially providing support to a joint where the angled sheath tip505is joined to the distal end513of the sheath503.

It should be noted that the insert410(that has the angled distal end423) (FIG.4) may be used with the angled sheath tip505that is formed separately from the sheath503, as described with reference toFIG.5. On the other hand, the insert510(that has the distal end523that is not angled) (FIG.5) may be used with the angled sheath tip405that is integrally formed with the sheath403, as described with reference toFIG.4. The present disclosure is not limited to the specific configurations of components literally shown in the figures, and elements shown in one illustrative embodiment may be combined with elements shown in other illustrative embodiments.

Referring toFIG.6, it may be desirable to form an angled sheath tip605that is both angled and deformable. Although the angled sheath tip605is shaped to conform to conform with a tissue surface610against which the angled sheath tip605may be extended, the angled sheath tip605may nonetheless impact the tissue wall at a contact point690where the tissue surface610may potentially incur some trauma from impact with the angled sheath tip605, or extension of the angled sheath tip605may result in relative displacement of the head201from the tissue wall610, as previously described with reference toFIG.3B. The angled sheath tip605thus may be formed to permit deformation665to absorb strain that may otherwise may potentially result in trauma from contact between the angled sheath tip605and the tissue surface610.

In providing for a degree of deformability and referring toFIGS.7A and7B, angled sheath tips705and755, respectively, each may include a construction different from that of the sheaths703and753, respectively, from which each angled sheath tip extends. Referring toFIG.7A, the angled sheath tip705may be formed of a same material as the sheath703but may have a different wall thickness than the sheath703. The angled sheath tip705may be formed along with the sheath703, or the angled sheath tip705may be formed separately from the sheath703and then joined with the sheath, as previously described with reference toFIGS.4and5. A wall thickness745of the angled sheath tip705may be different than a wall thickness743of the sheath703. For example, the wall thickness745of the angled sheath tip705may be thinner than that of the wall thickness743of the sheath703. As a result, even if the angled sheath tip705is comprised of a same material as the sheath703, the angled sheath tip705may be more deformable than the sheath703.

Referring toFIG.7B, the angled sheath tip755may be comprised of a material785that is different than a material783of which the sheath773is comprised. The material785of the angled sheath tip755may be more pliable or deformable than that of a material783used in forming the sheath753, thereby rendering the angled sheath tip755more deformable than the sheath753. A wall thickness795of the angled sheath tip755may be the same or different from a wall thickness793of the sheath753. A combination of different materials and/or different wall thicknesses may be combined to present an angled sheath tip having a desired degree of deformability to, along with the shaping of the angled sheath tip, potentially help reduce or prevent impact trauma or unwanted displacement between instruments and the tissue wall, as previously described with reference toFIG.3B.

Referring toFIG.8an illustrative method800of using a sheath tip in deploying an elongated instrument via a sheath is provided. The method800starts at a block805. At a block810, an elongated instrument is prepared for being conveyed into a body through a lumen in a sheath, wherein the sheath is to be extended toward a tissue at an angle to a surface of the tissue. The sheath includes a sheath tip at a distal end of the sheath where a distal end of the sheath tip is angled such that a periphery of the sheath tip at the distal end is configured to generally conform to the surface of the tissue toward which the sheath is extendable. Preparation for using the elongated instrument may include, for example, inserting a sheath housing an elongated instrument into an insertion system, maneuvering the insertion system to a desired location in a body, or other steps that logically may proceed deploying or using the elongated instrument. The configuration of angled sheath tips useable in accordance with the illustrative method800are described with reference toFIGS.2,3A,3B,4,5,6,7A, and7B.

At a block820, the sheath conveying the elongated instrument is inserted into the body. The insertion of the elongated instrument is described with reference toFIGS.1,2,3A,3B,4,5, and6. The method800ends at a block825.

It will be appreciated that the present descriptions of the sheath tips being used in the insertion of elongated instruments into a body via a sheath are not limiting to either the types of elongated instruments described or to use with medical instruments in a biological body. Sheath tips in the nature of those described could be used in any application where a lumen may contact a surface to which damage could result from impact of the lumen against the surface.

It will also be appreciated that the detailed description set forth above is merely illustrative in nature and variations that do not depart from the gist and/or spirit 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.