EUS access device with enhanced electrosurgical penetration

Abstract

The present invention relates to a device having a catheter, the catheter including a lumen extending therethrough, the catheter being sized and shaped to extend through an endoscope shaft to a target tissue in vivo. The device also includes a piercing device sized and shaped to extend through the lumen of the catheter and to extend distally out of the distal end of the catheter. The device also includes an electrode formed on at least one of the catheter and the piercing device. The electrode can be energized by the handle of the device so that when the piercing device extends distally out of the distal end of the catheter, the electrode can be energized when the device pierces the target tissue.

Description

[0001] Priority claim

[0002] This disclosure claims priority to U.S. Provisional Patent Application Serial No. 62 / 953,307, filed on December 24, 2019; the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to endoscopic ultrasound (EUS) access devices for accessing anatomical structures, such as the pancreaticobiliary tree. Background Art

[0004] Endoscopic ultrasound (EUS) access procedures (e.g., under ultrasound guidance) can be used to access anatomical structures such as the pancreaticobiliary tree and pancreatic pseudocysts. Pancreaticobiliary access procedures (such as procedures to insert a stent and bypass an obstruction) can be different from other types of access procedures in which the target anatomical structure is extremely narrow. Many EUS access devices lack maneuverability for biliary surgery, and even when they have sufficient maneuverability, other difficulties may be encountered. For example, a device with a long, thin sharp edge can easily form an initial puncture hole, but there is a risk of extending the sharp edge too far, for example, to the other side of the bile duct or penetrating other non-target tissues.

[0005] Furthermore, if the access cannula extends along the outer diameter of the sharp during initial puncture, the long sharp may not allow the access cannula to enter the puncture hole distally enough to maintain access to the tract after the sharp is removed. In another example, a device with a shorter and thicker sharp may have less risk of inadvertent puncture, but may be more difficult to perform an initial puncture (e.g., by increasing the force required to puncture the target tissue). In yet another example, a blunt access cannula may not be able to follow the sharp tip into the puncture hole. Summary of the invention

[0006] The present disclosure relates to a device, which includes a catheter, a piercing device, and an electrode formed on at least one of the catheter and the piercing device; the catheter includes a lumen extending therethrough, the size and shape of the catheter being set to extend through an endoscope shaft to a target tissue in a living body; the size and shape of the piercing device being set to extend through the lumen of the catheter and distally exit from the distal end of the catheter; the electrode can be energized by the handle of the device, so that when the piercing device extends distally from the distal end of the catheter, the electrode can be energized as the device pierces the target tissue.

[0007] In one embodiment, the distal end of the catheter is biased into a J-shaped bend when unconstrained.

[0008] In one embodiment, the distal end is rotatable about the longitudinal axis of the catheter to direct the distal opening of the distal end in a desired direction within the target tissue.

[0009] In one embodiment, when the piercing device pierces the target tissue, the distal end of the catheter follows the piercing device into the target tissue.

[0010] In one embodiment, the device further comprises an electrosurgical sheath longitudinally slidable along the exterior of the catheter, the electrosurgical sheath having an electrosurgical tip for dilating the access hole created in the target tissue by the piercing device.

[0011] In one embodiment, when the piercing device is extended into the distal end of the catheter, the distal end of the catheter is straightened.

[0012] In one embodiment, the electrode is formed at the distal end of the catheter.

[0013] In one embodiment, a proximal portion of the catheter between the distal end of the catheter and the distal end of the handle is formed of a non-conductive material, thereby also including conductive wires connecting the electrodes to the handle.

[0014] In one embodiment, the device further comprises an electrode formed at the distal end of the piercing device.

[0015] In one embodiment, the electrode is formed at the distal end of the piercing device.

[0016] In one embodiment, the device further comprises an insulating layer extending along the piercing device from the proximal end of the electrode to the proximal end of the piercing device.

[0017] In one embodiment, the handle also includes a length adjustment member; a sharp-edged hub; a piercing actuator that advances the piercing device and catheter distally out of the device's sheath; an electrosurgical sled that is slidably mounted on the piercing actuator to advance the sheath distally on the catheter to apply energy to the target tissue using electrodes formed on the sheath; a piercing actuator lock; an electrosurgical sled lock that is used to lock the sheath in a desired position relative to the catheter; and a first generator connection on the electrosurgical sled that is configured to connect to an electrical energy source.

[0018] In one embodiment, the handle further comprises a second generator connection on the piercing actuator configured to couple to a source of electrical energy and / or a third generator connection on the sharp-edged hub configured to couple to a source of electrical energy.

[0019] The present disclosure also relates to a system, which includes a catheter, a piercing device, an electrode formed thereon and included in at least one of the catheter and the piercing device, and an electrosurgical sheath; the catheter includes a lumen extending therethrough, the size and shape of the catheter being set to extend through the endoscope shaft to a target tissue in a living body; the size and shape of the piercing device being set to extend through the lumen of the catheter and extend distally out of the distal end of the catheter; the electrode can be energized by the handle of the device, so that when the piercing device extends distally out of the distal end of the catheter, the electrode can be energized when the device pierces the target tissue; the electrosurgical sheath is longitudinally slidable along the outside of the catheter, and the electrosurgical sheath has an electrosurgical tip for expanding an entry hole created by the piercing device in the target tissue.

[0020] In one embodiment, the distal end is rotatable about the longitudinal axis of the catheter to direct the distal opening of the distal end in a desired direction within the target tissue.

[0021] In addition, the present disclosure relates to a method, which includes extending a piercing device through a lumen of a catheter, the size and shape of the catheter being set to extend through an endoscope shaft to a target site in a living body, at least one of the catheter and the piercing device including an electrode formed thereon; energizing the electrode; piercing the target tissue with the piercing device; advancing the catheter distally through an access hole created in the target tissue by the piercing device; and withdrawing the piercing device proximally through the lumen and past the distal end of the catheter.

[0022] In one embodiment, the method further includes sliding an electrosurgical sheath along an exterior of the catheter, the electrosurgical sheath having an electrosurgical tip; positioning the electrosurgical tip in contact with tissue surrounding the access hole; and applying an electrical current to dilate the access hole.

[0023] In one embodiment, the method further comprises locking the electrosurgical sheath at a desired position relative to the catheter.

[0024] In one embodiment, the method further comprises rotating the distal end of the catheter about a longitudinal axis of the catheter to direct a distal opening of the distal end of the catheter in a desired direction within the target tissue.

[0025] In one embodiment, the electrode is formed at the distal end of the catheter. The method further includes energizing the electrode formed at the distal end of the piercing device before piercing the target tissue with the piercing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1a to Figure 1b The distal end of the endoscopic access device is shown.

[0027] Figure 2a An endoscopic access device having a long sharp edge is shown.

[0028] Figure 2bAn endoscopic access device with a short sharp edge is shown.

[0029] Figure 2c An endoscopic access device is shown having excess displacement formed between the sharp edge and the J-shaped tip.

[0030] Figure 3 The distal tip of the microcatheter is shown with an exposed metal end that can be powered for thermal puncture for an EUS access procedure.

[0031] Figure 4 A sharp edge is shown with an exposed metal end that can be energized for thermal puncture for an EUS access procedure.

[0032] Figure 5 A handle for controlling the EUS access procedure is shown.

[0033] Figure 6 Shown is a fine needle aspiration (FNA) needle with a blunted tip that can be energized for thermal puncture for an EUS access procedure. DETAILED DESCRIPTION

[0034] The present disclosure may be further understood with reference to the following description and accompanying drawings, in which similar elements are referred to by the same reference numerals. An exemplary embodiment describes an EUS access device having a thermal sharp and / or a J-shaped end for effective puncture and placement of the J-shaped end with low puncture force and a lower risk of failure to access the target tissue. In the present disclosure, the term "hot" refers to an element that is activated electrosurgically. The thermal elements are designed so that when activated, they pass an electric current through the tissue, but remain relatively unheated while they pass the electric current through the target tissue, so that the resistance of the target tissue causes heating and boiling of the target tissue, thereby allowing the target tissue to be cut and expanded. In the present disclosure, the term "cold" refers to an element that is not activated electrosurgically.

[0035] Figure 1a to Figure 1b An exemplary EUS access device 100 is shown including a microcatheter 102 (i.e., access cannula) having a flexible distal tip 104 that is biased into a natural J-shape (J-shaped tip) when unconstrained. A piercing element 106 having a pointed tip (i.e., sharp edge) is advanced through the lumen of the microcatheter 102 such that the flexible J-shaped tip 104 is straightened by the rigidity of the sharp edge 106 until the sharp edge 106 extends distally out of the distal end of the J-shaped tip 104 by a desired distance so that the sharp edge 106 can be used to pierce the target tissue, whereupon the sharp edge 106 and the J-shaped tip 104 can be advanced together into the target anatomical structure.

[0036] The distance 108 that the distal end of the sharp edge 106 extends distally beyond the distal end of the J-shaped tip 104 (when the sharp edge 106 is inserted therein) is referred to as "setback." After the J-shaped tip 104 and sharp edge 106 are advanced into the target anatomical structure as desired, the sharp edge 106 is withdrawn proximally away from the J-shaped tip 104, thereby returning the J-shaped tip 104 to its curved J-shape, such as Figure 1b Then, a guidewire may be inserted through the lumen of the microcatheter 102 and out of the distal end of the J-shaped tip 104 into the target anatomical structure. Before, during, or after the guidewire is inserted into the microcatheter 102, the J-shaped tip 104 may be rotated so that the distal opening of the J-shaped tip 104 is directed in a desired direction within the target anatomical structure.

[0037] For example, in the case where the target anatomical structure is a bile duct, the J-shaped end 104 can be rotated so that the distal opening of the lumen of the microcatheter 102 faces the upstream of the bile duct or downstream toward the bile duct to the outlet of the small intestine. When the J-shaped end 104 is oriented as required, the guide wire passes through the microcatheter 102 and exits the opening at the distal end of the J-shaped end 104, and extends away from the J-shaped end 104 in the desired direction along the bile duct to reach a desired distance. At this time, the flexible electrosurgical sheath 110 with an electrosurgical end 112 can be advanced on the microcatheter 102 and the J-shaped end 104 to expand the hole through which the microcatheter 102 exits the small intestine and the hole through which the microcatheter 102 enters the target bile duct. The electrosurgical end can expand the access hole (fistula) to, for example, 5 to 11Fr. As understood by those skilled in the art, when the electrosurgical end is located at the entrance of the hole and in it, the electrode of the end can be activated to cut and widen the hole to facilitate access to the target anatomical structure for other procedures (for example, stents are placed therein to bypass blockages).

[0038] The sharp edge 106 is typically used to form an initial hole in the anatomical structure through which the wider diameter J-shaped tip 104 can be pushed so that the J-shaped tip 104 is firmly inserted through the puncture hole in the target anatomical structure when the sharp edge 106 is removed. However, various complications can occur when performing such an operation.

[0039] For example, an access device 200 (eg, Figure 2aThe sharp edge 201 (shown) can easily pierce tissue 203, that is, reduce the piercing force necessary to form the hole. However, the long setback between the distal end of the sharp edge 201 and the distal end of the J-shaped tip 202 requires that the sharp edge be pushed further into the tissue 203 before the J-shaped tip 202 is firmly inserted into the piercing hole. Therefore, with a long and thin sharp edge 201, it is possible to push the sharp edge 201 too far distally, thereby inadvertently piercing tissue 204 distal to the initially pierced tissue 203. On the contrary, if the long sharp edge 201 is not pushed far enough to firmly entrench the J-shaped tip 202, the J-shaped tip 202 may gradually move away from the piercing hole and fall out of it when the sharp edge 201 is removed.

[0040] In another example, an access device 210 (eg, Figure 2b The J-shaped tip 212 may not accidentally pierce tissue 214 distal to the initial pierced tissue 213 or fall out of the pierced hole. However, the force required to pierce the target tissue with a device including such a thickened sharp edge 211 is increased compared to those devices with long and thin sharp edges.

[0041] In yet another example, the access device 220 may have a J-shaped tip 222 that grips the wall of the anatomical structure as the sharp edge 221 is advanced through the tissue 223 (eg, Figure 2c 221 and the J-shaped tip 222, thereby causing displacement between the sharp edge tip 221 and the J-shaped tip 222 and pushing the tissue 223 distally when the J-shaped tip 222 is pressed against the tissue wall (i.e., bulging). When a blunt or poorly tapered J-shaped tip is used, bulging can occur. However, a J-shaped tip with a sharper edge may damage surrounding tissue when the J-shaped tip is rotated within the bile duct to guide the guidewire.

[0042] The exemplary embodiments describe an EUS access device having one or more energized features for thermal puncture to address the aforementioned problems. An electrosurgical generator (such as an Erbe generator) can be used to apply RF cutting current to the device to allow the puncture tip to easily pass into tissue with low puncture force. The device can be generally similar to Figure 1a to Figure 1b A modification of the device described in will be described below.

[0043] Figure 3The distal end 300 (J-shaped end) of the microcatheter is shown to have an exposed metal end 302, which can be energized for thermal puncture in the EUS access procedure. The metal end 302 is passivated to minimize the trauma to the surrounding tissue when the J-shaped end 300 (in its curved configuration) is rotated in the bile duct to guide the guide wire as needed. As will be appreciated by those skilled in the art, any sharp edge can be used with the distal end 300. However, a shorter sharp edge can be used without increasing the required piercing force. As described above, the use of a cold and blunt J-shaped end with a short sharp edge requires an increased piercing force. However, a hot and blunt J-shaped end has been shown to pierce with a relatively low piercing force. In the present embodiment, the hot and blunt J-shaped end can have a minimum retraction of approximately 0.5 mm.

[0044] When the microcatheter is entirely metal, the entire microcatheter is insulated except for the exposed metal end 302 to prevent heating or cutting of non-target tissue (i.e., tissue other than the target site). For example, the length of the exposed metal end 302 can be less than 1 mm to minimize thermal damage to the target site during cutting. The exposed metal end 302 of the thermal J-shaped tip 300 can also be wired to the handle, and the rest of the microcatheter can be formed of a different non-conductive material, thereby eliminating the need for a separate electrically insulating coating.

[0045] Figure 4 A sharp edge 400 is shown with an exposed metal end 402 that can be energized for hot puncture for an EUS access procedure. The exposed metal end 402 can be a short, sharpened end, or can be relatively blunt. When the metal end 402 is sharpened, the sharp edge 400 can also be used for cold puncture. However, if the attempt at cold puncture is unsuccessful, the user has the option of energizing the exposed metal end 402 for hot puncture.

[0046] Similar to thermal J-tip 300, thermal sharp 400 may have a flexible shaft of the same conductive material (e.g., metal) as exposed metal end 402, but insulated along its length (except for exposed metal end 402). If the access cannula used with sharp 400 is not intended to have a thermal J-tip, then the J-tip may be insulated to prevent power from sharp 400 from being conducted through the J-tip. Alternatively, the J-tip may not be insulated, so the access device will have both a thermal sharp and a thermal J-tip. In this case, only one of the J-tip or the sharp needs to be connected to the electrosurgical generator (via wire, or otherwise) to effectively energize both ends.

[0047] Although the hot sharp edge cuts well enough to allow the cold and blunt J-shaped end to pass through the fistula, energizing both ends can further reduce the piercing force. However, which one of the J-shaped end and the sharp edge is selected or both are energized can depend on the nature of the intervention. For example, the hot J-shaped end has been shown to form a larger fistula than the cold J-shaped end. Considering that the fistula still needs to be processed larger with an electrosurgical dilator before the stent is implanted, a larger fistula will not affect procedures such as stent implantation. However, for procedures (e.g., convergence procedures) that require smaller holes, it is preferred to energize the sharp edge with a cold J-shaped end than to energize both the sharp edge and the J-shaped end.

[0048] In an alternative embodiment, a hot and blunt stylet can be used instead of a sharp edge. The stylet has a blunt distal end, as opposed to a sharp edge with a sharpened distal end. In this embodiment, the stylet and J-shaped tip can have a very short setback, e.g., 2 mm, to ensure that when the tip of the stylet passes into the tract, the access cannula also passes into the tract. This embodiment allows for targeting of smaller tissues because there is less risk of the tip extending to the opposite side of the tract and accidentally piercing the opposite side.

[0049] The foregoing embodiments may be implemented endoscopy, where the device has a handle for controlling endoscopic procedures.

[0050] Figure 5 A handle 500 is shown for controlling an EUS access procedure. The handle 500 extends from a proximal sharp hub 502 to a distal collar 504, which is attached to a connector at the proximal end of the endoscope shaft. The sharp hub 502 is connected to the sharp so that the sharp hub 502 can be pulled to withdraw the sharp from the device. The sharp hub 502 includes a generator connection 520, where an electrical energy source can be connected to the device. The handle 500 includes a length adjustment member 506, via which a user can adjust the length of the handle 500 so that when connected to an endoscope, the length of the electrosurgical sheath extends distally beyond the distal end of the endoscope to a desired distance (i.e., the length adjustment member can be used to achieve extension of the device from the endoscope). The handle 500 also includes a piercing actuator 508 that can slide on the base 512 of the handle 500 so that when unlocked via the piercing actuator lock 510, the J-shaped tip and sharp edge are advanced distally out of the sheath (e.g., the electrosurgical sheath 110 shown in FIG. 1 ) so that the J-shaped tip and sharp edge can pierce the target tissue to a desired depth. The piercing actuator 508 includes a generator connection 522 where an electrical energy source can be coupled to the device.

[0051] The handle 500 also includes an electrosurgical sled 514 slidably mounted on the piercing actuator 508 so that the sheath can be advanced distally over the J-shaped end to bring the electrosurgical tip (e.g., electrosurgical tip 112 shown in FIG. 1 ) at the distal end of the sheath into contact with the target tissue so that the tissue can be treated by the application of energy from the tip (e.g., cutting and dilating the tissue surrounding the opening formed through the wall of the gastrointestinal tract and the entrance to the target pancreaticobiliary duct lumen). The electrosurgical sled 514 includes a generator connection 516 where an electrical energy source can be coupled to the device. The electrosurgical sled 514 is maintained at a desired position on the piercing actuator 508 via an electrosurgical sled lock 518. Similar to the piercing actuator lock 510, the electrosurgical sled lock 518 includes a protrusion that engages a gear drive surface on the base 512 until the corresponding lock is recessed to disconnect from the base 512, thereby allowing the piercing actuator 508 or the electrosurgical sled 514 to slide on the base 512.

[0052] The generator connection 516 provides a connection to electrical energy that can be transmitted to the electrosurgical sled 514. The generator connections 520 and 522 provide energy to each of the metal end 402 of the sharp edge and the metal end 302 of the microcatheter J-shaped end in the manner described above. A depth indicator may be provided on the base 512 to provide more control over the penetration depth of the sharp edge / J-shaped end and the length of the electrosurgical sheath. As previously shown, the ideal penetration depth may be different for different procedures and different sharp edge / J-shaped end configurations. Therefore, the handle 500 is compatible with different access devices having different penetration depths while having controllability to the exact penetration depth.

[0053] Figure 6 A fine needle aspiration (FNA) needle 600 is shown with a blunt end 602 that can be energized for thermal puncture during an EUS access procedure. The FNA needle 600 has a lumen for a guidewire to extend through. A blunt (as opposed to a sharp edge) needle allows for easier guidewire directionality, with a lower risk of the needle abrading the guidewire. The blunt end 602 (although blunt) is able to pierce anatomical structures when energized.

[0054] Each of the aforementioned energized piercing features can be actuated via an electrosurgical plug that extends from or is built into the endoscope handle. The hot tip feature can be actuated at any time during an endoscopic intervention. Thus, a clinician can begin a procedure using, for example, a cold sharp-edge tip, and when a cold piercing is unsuccessful, actuate the hot tip and perform a hot piercing.

[0055] It will be appreciated by those skilled in the art that changes may be made to the above embodiments without departing from the principles of the invention. It will also be appreciated that structural features and methods associated with one of the embodiments may be incorporated into other embodiments. Therefore, it will be appreciated that the invention is not limited to the specific embodiments disclosed, but modifications are within the scope of the invention as defined by the appended claims.

Claims

1. A device comprising: a catheter having a flexible distal tip, the catheter including a lumen extending therethrough, the catheter being sized and shaped and having the flexible distal tip sufficiently flexible to pass through an endoscope shaft to a target tissue in vivo; a piercing device having a flexible shaft and sized and shaped to extend through the lumen of the catheter and distally out of the distal end of the catheter; an electrode formed thereon and included in at least one of the catheter and the piercing device, the electrode being energizable by a handle of the device so that when the piercing device extends distally out of the distal end of the catheter, the electrode is energized when the piercing device pierces the target tissue; and A flexible electrosurgical sheath is longitudinally slidable along the exterior of the catheter, the flexible electrosurgical sheath having an electrosurgical tip for dilating an access hole in the target tissue formed by the piercing device.

2. The device of claim 1, wherein the distal end of the catheter is biased into a J-shaped bend when unconstrained.

3. The device according to claim 1 or 2, wherein the distal end is rotatable about the longitudinal axis of the catheter to direct the distal opening of the distal end in a desired direction within the target tissue.

4. The device according to claim 1, wherein when the piercing device pierces the target tissue, the distal end of the catheter is configured to follow the piercing device into the target tissue.

5. The device of claim 1, wherein when the piercing device extends into the distal end of the catheter, the distal end of the catheter is straightened. The device according to claim 1 , wherein the electrode is formed at a distal end of the catheter.

7. The device of claim 6, wherein a proximal portion of the catheter between a distal end of the catheter and a distal end of the handle is formed of a non-conductive material, and further comprising a conductive wire connecting the electrode to the handle.

8. The apparatus according to claim 6, further comprising: Another electrode is formed at the distal end of the piercing device.

9. The device of claim 1, wherein the electrode is formed at a distal end of the piercing device.

10. The apparatus according to claim 9, further comprising: An insulating layer extends along the piercing device from the proximal end of the electrode to the proximal end of the piercing device.

11. The device of claim 1 , wherein the handle further comprises: Length adjustment piece; Sharp edge hub; a piercing actuator that distally advances the piercing device and the catheter out of a sheath of the device; an electrosurgical sled slidably mounted on the piercing actuator to advance the sheath distally over the catheter to apply energy to the target tissue using a further electrode formed on the sheath; piercing the actuator lock; an electrosurgical slide lock that locks the sheath in a desired position relative to the catheter; and A first generator connection on the electrosurgical sled is configured to be coupled to a source of electrical energy.

12. The device of claim 11, wherein the handle further comprises a second generator connection on the piercing actuator configured to be connected to an electrical energy source and / or a third generator connection on the sharp-edge hub configured to be connected to an electrical energy source.

13. A system comprising: a catheter having a flexible distal tip, the catheter including a lumen extending therethrough, the catheter being sized and shaped and having the flexible distal tip sufficiently flexible to pass through an endoscope shaft to a target tissue in vivo; a piercing device sized and shaped to extend through the lumen of the catheter and distally out of the distal end of the catheter; and The catheter and the piercing device both include electrodes formed thereon, the electrodes of the catheter and the electrodes of the piercing device being energizable by the handle of the device, so that when the piercing device extends distally out of the distal end of the catheter, the electrodes of the piercing device are energized when the piercing device pierces the target tissue; and A flexible electrosurgical sheath is longitudinally slidable along the exterior of the catheter, the flexible electrosurgical sheath having an electrosurgical tip for dilating an access hole in the target tissue formed by the piercing device.

14. The system of claim 13, wherein the distal end is rotatable about a longitudinal axis of the catheter to direct a distal opening of the distal end in a desired direction within the target tissue.

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