GB2582318A

GB2582318A - Electrosurgical device

Info

Publication number: GB2582318A
Application number: GB1903712.6A
Authority: GB
Inventors: Tulp Nicholas
Original assignee: Gyrus Medical Ltd
Current assignee: Gyrus Medical Ltd
Priority date: 2019-03-19
Filing date: 2019-03-19
Publication date: 2020-09-23
Anticipated expiration: 2039-03-19
Also published as: GB201903712D0; GB2582318B

Abstract

An electrosurgical end effector 26 with a rotary shaver 40 being tubular with an open distal end and having a cutting portion 38. There is an active electrode 32 on an insulative carrier 30 projecting through the tubular shaver element. An operating surface 324 of the electrode faces the same direction as the operating cutting direction of the cutting element of the rotatable tubular element. The tubular element may have a cut-out portion having one or more sharpened edges 38 to form a cutting instrument. There may be a second tubular element 36 with a cutting window 66. In use a RF electrosurgical generator supplies an RF tissue sealing or ablation signal to the electrode. This allows the electrode and blade to operate in the same direction, with may be orthogonal to the long axis of the arrangement, allowing simultaneous mechanical cutting and electrosurgical coagulation or ablation. The end effector may be used with a hand piece in a system with a suction source.

Description

ELECTROSURGICAL DEVICE

Technical Field

Embodiments of the present invention described herein relate to an electrosurgical device, and in particular to an electrosurgical device wherein a rotating cylindrical blade provides a tissue cutting action in combination with electrosurgical electrodes providing a tissue ablation, coagulation, or sealing effect.

Background to the Invention and Prior Art

Electrosurgical instruments provide advantages over traditional surgical instruments in that they can be used for coagulation and tissue sealing purposes. One such prior art arrangement is known from US 5,904,681, which describes a surgical instrument including a mechanical cutting portion, such as a rotary blade or burr, and a radio frequency (RF) cutting and/or cauterizing portion comprising an electrosurgical instrument which operates in bipolar mode. A rotary burr works best to remove hard tissues, such as bone, while the bipolar electrosurgical instrument can be used to cut or ablate soft tissues and/or cauterize tissue, including blood vessels. Alternatively, the mechanical cutting portion may include a rotary blade, which may be used for removing soft tissues, with the electrodes of the electrosurgical system being used for cauterisation or coagulation.

Another prior art arrangement is known from WO 2016/171963 Al, which describes an elongated shaft assembly including a rotatable inner cutting sleeve and a non-rotating outer sleeve. A window of the inner cutting sleeve is selectively rotatable within an opening of the non-rotating outer sleeve to cut tissue with a sharpened cutting blade when rotated in a first rotational direction and to cut tissue with an electrode when rotated in a second, opposite, rotational direction.

A further prior art arrangement is known from US 9,226,792 B2, which describes arrangements for cutting and sealing of tissue such as bone and soft tissue. Such arrangements include the delivery of energy including bipolar radiofrequency energy for sealing tissue which may he concurrent with delivery of fluid to a targeted tissue site, from a fluid source. One arrangement includes inner and outer shafts coaxially maintained and having cutters for debridement of tissue. An inner shaft includes electrodes apart from the cutter to minimize trauma to tissue during sealing or hemostasis. A single, thin liner or sheath for electrically isolating the inner and outer shafts may be included.

Summary of the Invention

Embodiments of the present invention provide an improved surgical instrument having an end effector mounted on the end of an elongate shaft extending from a handle. The end effector is capable of different operations, including mechanical cutting of tissue, and electrosurgical ablation, sealing and/or coagulation of tissue, with mechanical cutting and electrosurgical ablation, sealing or coagulation of tissue capable of taking place in the same plane simultaneously. In this respect, the end effector comprises an open ended tubular design, having a rotatable cylindrical element co-axially arranged therein, the cylindrical element having a cut-out portion having one or more sharpened edges to form a cutting instrument, and the tube containing the cylinder also having a corresponding cut-out portion, which may also have sharpened edges that in use provided a scissor like tissue cutting action in conjunction with the sharpened edges of the rotatable cylindrical element when the rotatable cylindrical is rotated within the tube, with the mechanical cutting action being directed in a cutting direction that is substantially orthogonal to the long axis of the instrument. The rotatable cylindrical element has an open distal end through which projects an electrically insulative electrode carrier, mounted on which is a substantially planar active electrode, which is connected by wires running in or along the electrode carrier within the rotatable cylindrical element to permit the active electrode to be connected to a RF electrosurgical generator. In use the RF electrosurgical generator supplies an RF ablation, or coagulation or tissue sealing signal to the electrode under control of the operator, as appropriate. The plane face of the active electrode faces substantially the same direction as the cut-out portion in the tube, which allows a significant area of the active electrode to face the mechanical cutting direction. This in turn allows the electrode and blade to operate in the same direction, being substantially orthogonal to the long axis of the arrangement, allowing simultaneous mechanical cutting and electrosurgical ablation, sealing, or coagulation. Such an arrangement is advantageous, as by being able to simultaneously cut and cauterize tissues at the surgical site, a clear view of the surgical site can be maintained, which could otherwise be obscured by excessive bleeding. Alternatively, when used for both mechanical cutting and electrosurgical ablation at the same time, then tissue removal can be performed very quickly.

In view of the above, from one aspect the present invention provides an electrosurgical end effector, comprising: a rotary shaver arrangement, having a rotatable tubular demerit with a cutting portion having a cutting blade formed therein that when in use is able to cut tissue located in an operative cutting direction, the rotatable tubular clement having an open distal end; and an electrically insulative carrier projecting distally of the rotatable tubular element through the open distal end thereof, the electrically insulative carrier having an active electrode mounted thereon, an operative major surface of the active electrode facing the same direction as the operative cutting direction of the cutting element of the rotatable tubular element; the arrangement being such that when in operation the electrosurgical end effector is able to cut tissue located in the operative cutting direction using the cutting blade and apply an RF electrosurgical signal to the same tissue located in the operative cutting direction.

Such an arrangement improves upon the known RF shaver arrangements of the prior art by allowing the mechanical cutting action and the RF coagulation or ablation action to act in the same direction on the same tissue. This can make the instrument easier to use, as the surgeon does not need to re-orient the instrument to obtain the mechanical cutting action or the electrosurgical coagulation or ablation action at the same place.

In one embodiment the arrangement is such that the rotary shaver arrangement and the active electrode are operated at the same time, such that tissue is cut and RF electrosurgical signal is applied to the tissue simultaneously. The RF electrosurgical signal is in many examples a coagulation signal. Such operation then allows both a cutting and a coagulation operation to be undertaken at the same time on the same tissue. This can reduce bleeding and when the instrument is being operated in "wet mode" within a saline solution can improve the visibility of the operating area by the surgeon. Alternatively, the RF electrosurgical signal may be an ablation signal, whcih is used to ablate tissue. By both mechanically cutting and electorsurgically ablating tissue in the same operative direction with respect to the instrument simultaneously, then bulk removal of tissue can be performed very quickly.

In one embodiment the operative mechanical cutting direction is substantially orthogonal to a long axis of the rotatable tubular element around which the tubular clement rotates. In such example the instrument is therefore a "side effect" instrument, which operates on tissue to the side of the end-effector.

In one example the rotatable tubular element has a long axis that extends in the distal direction, a section of the wall of the tubular element towards the distal end thereof being removed and at least part of the walls of the element around the section being sharpened in one or more places to form the cutting blade; the end effector further comprising a second tubular element extending in the distal direction and concentrically arranged around the rotatable tubular element, the second tubular element having a cutting window formed in the wall thereof at a position such that the cutting blade of the rotatable tubular clement is located within the window, the second tubular element being open at the distal end thereof, the arrangement being such that when in use rotation of the rotatable tubular element within the second tubular element causes a tissue cutting action of the cutting blade interacting with the cutting window.

In the example above the walls of the tubular clement on both sides of the removed section may be sharpened, wherein the rotatable cutting element is able to cut when rotated in either direction about its long axis. In addition, in another example one or more of the sharpened sections may be serrated.

In one example the second tubular element is formed from conductive material and in use acts as a return electrode. This provides a convenient bipolar arrangement and ensures that electrical current flows only in the tissue that is intended to be treated. In one embodiment the insulative carrier extends from within the rotatable tube and projects distally out of the open end thereof, the projecting part having a planar electrode carrying portion mounting the active electrode and facing in the operative cutting direction. The open faced nature of the cutting tube permits this arrangement, and thereby allows the carrier to face in the same direction as the operative direction of the cutting blade.

Moreover, in a further embodiment the projecting part of the insulative carrier has a curved distal face, and a flat upper surface facing in the operative direction that acts as the planar electrode carrying portion, the curved distal face extending in a curved around to the peripheral sides and bottom side of the carrier, opposite the flat upper surface, the insulative carrier further comprising a stem portion that extends longitudinally back through the rotatable tubular element, the stem portion carrying electrical connections to permit connection of the active electrode to an clectrosurgical generator when in use. In some examples the insulative carrier is formed from ceramic.

In one embodiment the rotary shaver arrangement further comprises an insulative tube that concentrically surrounds the rotatable tubular element, and has an open end such that the rotatable tubular element projects therefrom.

In one embodiment the interior of the rotatable tubular element in use acts as a suction lumen to permit the aspiration of cutting debris during use.

Another aspect of the present disclosure provides an electrosurgical instrument, comprising: a hand-piece; one or more user-operable buttons on the handpicce that control the instrument to operate, and an operative shaft, having RF electrical connections, and drive componentry for an end effector, the electrosurgical instrument further comprising an end effector as described above, the rotary shaver arrangement.

being operably connected to the drive componentry to drive the rotary shaver to operate in use, and the active electrode being connected to the RF electrical connections.

A yet further aspect provides an electrosurgical system, comprising: an RF electrosurgical generator; a suction source; and an electrosurgical instrument as described in the above aspect, the arrangement being such that in use the RF electrosurgical generator supplies an RF electrosurgical signal via the RF electrical connections to the active electrode, to permit tissue treatment of the same tissue that is being cut by the rotary shaver arrangement. The RF electrosurgical signal may be a coagulation signal, or an ablation signal.

Brief Description of the Drawings

Embodiments of the invention will now be further described by way of example only and with reference to the accompanying drawings, wherein like reference numerals refer to like parts, and wherein: Figure 1 is a schematic diagram of an electrosurgical system including an electrosurgical instrument according to an embodiment of the present invention; Figure 2 is a side view of an electrosurgical instrument according to an embodiment of the present invention; Figure 3 is a perspective view of the tip of Figure 2, wherein the rotating shaver blade's cutting edges are facing upwards; Figure 4 is a perspective view of the tip of Figure 2, whcrcin the rotating shaver blade's cutting edges arc facing downwards (cutting edges cannot be seen); Figure 5 is a plan view of the tip of Figure 2, wherein the rotating shaver blade's cutting edges are facing upwards; Figure 6 is a side view of the tip of Figure 2, wherein the rotating shaver blade's cutting edges are facing upwards; Figure 7 is a side view of the tip of Figure 2, wherein the rotating shaver blade's cutting edges are facing downwards; and Figure 8 is an end view of the tip of Figure 2, wherein the rotating shaver blade's cutting edges are facing upwards.

Description of the Embodiments

Referring to the drawings, Figure 1 shows electrosurgical apparatus including an electrosurgical generator 1 having an output socket 2 providing a radio frequency (RF) output, via a connection cord 4, for an electrosurgical instrument 12. The instrument 12 has irrigation and suction tubes 14 which are connected to an irrigation fluid and suction source 10. Activation of the generator 1 may be performed from the instrument 12 via a handswitch (not shown) on the instrument 12, or by means of a footswitch unit 5 connected separately to the rear of the generator 1 by a footswitch connection cord 6. In the illustrated embodiment, the footswitch unit 5 has two foots witches 5a and 5b for selecting a coagulation mode or a cutting or vaporisation (ablation) mode of the generator 1 respectively, although in some embodiments of the electrosurgical instrument 12 described herein it is envisaged that only one or other of the coagulation or ablation modes would be used, with cutting being provided mechanically by way of a rotating tube having a sharpened cut-out portion, described further below. The generator front panel has push buttons 7a and 7b for respectively setting ablation (cutting) or coagulation power levels, which are indicated in a display 8. Push buttons 9 are provided as an alternative means for selection between the ablation (cutting) and coagulation modes.

Figure 2 shows the electrosurgical instrument 12 forming the basis of an embodiment of the present invention. The instrument. 12 includes a proximal handle portion 22, a hollow shaft 24 extending in a distal direction away from the proximal handle portion, and a distal end effector assembly 26 at the distal end of the outer shaft. A power connection cord 4 connects the instrument to the RF generator I, whereas tubes 14 connect the instrument to the irrigation and suction source 10. The instrument may further be provided with activation buttons (not shown), to allow the surgeon operator to activate either the mechanical cutting function of the end effector, or the electrosurgical functions of the end effector, which in this embodiment typically comprise coagulation or ablation.

Figures 3 to 8 show the distal end effector assembly 26 in more detail. With specific reference to Figures 6 and 7, the end effector comprises a series of concentrically arranged tubes, with outer insulating sheath 34 containing a hollow conductive tube 36, having at is distal end an open end and an opening cut out of one side thereof to act as a cutting window 66. The edges of the cutting window 66 may be sharpened to provide scissor action in use against a cutting edge 38 of a cylindrical rotatable shaver element 40. The hollow, distally open-ended conductive tube 36 acts as a return electrode and concentrically surrounds a rotatable cylindrical shaver clement 40. By 'concentrically surrounds' we mean that the shaver element 40 is inside and coaxial with the tube 36. The proximal part of the tube 36 is covered with the insulating sheath 34. The distal part of the tube 36 has the opening which acts as the cutting window 66. The shaver blade itself is a hollow cylinder of C-shape cross-section at the distal end, meaning a hollow cylinder which has a segment cut out for a portion of the distal end, so that the cylinder is incomplete at the distal end. The cut out portion is sharpened and serrated, to form the cutting edge 38.

As just noted, at the distal end of the end effector, the shaver blade 40 has a sharp cutting edge 38, which may be serrated or shaped into points to provide cutting teeth. The hollow open-ended shaver blade 40 in use defines an internal suction lumen 62, which extends along the shaft 24 and ultimately connects to the suction source 10. Disposed within the hollow shaver blade 40 is a pipe-shaped insulating ceramic body 30. The ceramic body 30 comprises an elongate stem portion 302, and an upturned head portion 64 which extends out of the open end of the shaver blade 40 beyond the distal end of the shaver blade 40 and the shaft 36. Mounted on an upper plane surface 322 of the ceramic body 30 is the active electrode 32. The active electrode 32 has a portion 304 which runs along ceramic stern portion 302 back to the generator 1 via the connection cord 4. A significant planar portion 324 of the active electrode 32 mounted on the head of the ceramic 64 faces upwards in the same direction as the cutting edges 38. A smaller portion of the active electrode 322 is forward facing, constituting the distal-most part of the active electrode 32. Effectively, however, the planar portion 324 faces orthogonally to the long axis of the instrument, and is effective in the same direction as the shaver blade 40. That is, as explained further below, the shaver blade 40 is operative when in use to cut tissue that it is presented against and which is located in a direction to the side of the shaft of the instrument i.e. in a direction orthogonal to the long axis of the instrument. The active electrode 32, due to the large planar face 324 also operatively faces in the same direction as the operative direction of the shaver blade 40, so that in use it may coagulate or ablate tissue that is also in the same direction to the side of the shaft of the instrument i.e. in the same orthogonal direction to the long axis of the instrument as the operative direction of the shaver blade, depending on the operating mode. As a consequence of this arrangement, in operation in one mode the instrument is able to simultaneously cut tissue located to the side of the issue using the rotating shaver blade at the same time as coagulating that same tissue using the active electrode. In another mode, the instrument. is able to simultaneously cut tissue located to the side of the issue using the rotating shaver blade at the same time as ablating that same tissue using the active electrode; this permits for very quick tissue removal.

In more detail, to electrosurgically coagulate or ablate tissue, the user manipulates the instrument 12 such that the active electrode 32 is adjacent to the tissue to he treated, and activates the generator 1 to supply RF power to the active electrode 32, via the connection cord 4. The RF signal supplied is dependend on whether the active electrode is to simply coagulate (dessicate) tissue, or to ablate the tissue, wherein a higher power RF signal is used for (issue ablation than (issue coagulation. The active electrode 32 and the return electrode 36 act in a bipolar electrode arrangement. The suction lumen 62 is connected to the suction source 10 such that fluid, tissue fragments, bubbles or other debris in the vicinity of the electrode 32 can be aspirated from the surgical site. As noted above, the tissue to he treated is located adjacent the side of the instrument, in a direction orthogonal to the long axis of the instrument.

To mechanically cut tissue, the user manipulates the instrument 12 such that the cutting window 66 is in contact with the tissue to be cut. The shaver blade 40 can be rotated by a motor in a first rotational direction relative to the shaft 36 to cut tissue engaged by the cutting edges 38 on one side of the shaver blade 40, typically by shearing with an opposed edge on the cutting window 66 of the shaft 36. The inner sleeve can also be rotated by a motor in a second rotational direction opposite to the first rotational direction to cut tissue engaged by the cutting edges 38 on the other side of the shaver blade 40. As noted above, the tissue to be cut is located adjacent the side of the instrument, in a direction orthogonal to the long axis of the instrument, and notably in the same direction as the operative direction of the active electrode 32.

The use of the shaver blade 40 and the electrode 32 can be simultaneous. This is possible as the described example is an open ended tubular design, which still has bidirectional cutting edges 38. This allows a significant portion of the electrode 324 to be positioned facing the same direction (upwards) as the cutting window 66. This means the electrode 32 and the shaver blade 40 can operate on the same section of tissue simultaneously, such that both mechanical cutting of the tissue (using the blade 40), and electrosurgical coagulation or ablation of the tissue (using the active electrode 32) can be obtained simultaneously.

Various modifications whether by way of addition, deletion, or substitution of 20 features may be made to above described embodiment to provide further embodiments, any and all of which are intended to be encompassed by the appended claims.

Claims

Claims 1. An electrosurgical end effector, comprising: a rotary shaver arrangement, having a rotatable tubular element with a cutting portion having a cutting blade formed therein that when in use is able to cut tissue located in an operative cutting direction, the rotatable tubular element having an open distal end; and an electrically insulative carrier projecting distally of the rotatable tubular element through the open distal end thereof, the electrically insulative carrier having an active electrode mounted thereon, an operative major surface of the active electrode facing the same direction as the operative cutting direction of the cutting element of the rotatable tubular element; the arrangement being such that when in operation the electrosurgical end effector is able to cut tissue located in the operative cutting direction using the cutting blade and apply an RF electrosurgical signal to the same tissue located in the operative cutting direction.
2. An electrosurgical end effector according to claim 1, wherein the arrangement is such that rotary shaver arrangement and the active electrode are operated at the same time, such that tissue is cut and a RF electrosurgical signal is applied to the tissue simultaneously.
3. An electrosurgical end effector according to claims 1 or 2, wherein the RF electrosurgical signal is one of: i) a coagulation signal; or ii) an ablation signal.
4. An electrosurgical end effector according to any of the preceding claims, wherein the operative cutting direction is substantially orthogonal to a long axis of the rotatable tubular element around which the tubular element rotates.
5. An electrosurgical end effector, wherein the rotatable tubular element has a long axis that extends in the distal direction, a section of the wall of the tubular element towards the distal end thereof being removed and at least part of the walls of the element around the section being sharpened in one or more places to form the cutting blade; the end effector further comprising a second tubular clement extending in the distal direction and concentrically arranged around the rotatable tubular element, the second tubular element having a cutting window formed in the wall thereof at a position such that the cutting blade of the rotatable tubular element is located within the window, the second tubular clement being open at the distal end thereof, the arrangement being such that when in use rotation of the rotatable tubular element within the second tubular element causes a tissue cutting action of the cutting blade interacting with the cutting window.
6. An electrosurgical end effector according to claim 5, wherein the walls of the tubular element on both sides of the removed section being sharpened, wherein the rotatable cutting element is able to cut when rotated in either direction about its long axis.
7. An electrosurgical end effector according to claims 5 or 6, wherein one or more of the sharpened sections are serrated.
8. An electrosurgical end effector according to any of claims 5 to 7, wherein the second tubular element is formed from conductive material and in use acts as a return 20 electrode.
9. An electrosurgical end effector according to any of the preceding claims, wherein the insulative carrier extends from within the rotatable tube and projects distally out of the open end thereof, the projecting part having a planar electrode carrying portion mounting the active electrode and facing in the operative cutting direction.
10. An electrosurgical end effector according to claim 8, wherein the projecting part of the insulative carrier has a curved distal face, and a flat upper surface facing in the operative direction that acts as the planar electrode carrying portion, the curved distal face extending in a curved around to the peripheral sides and bottom side of the carrier, opposite the flat upper surface, the insulative carrier further comprising a stem portion that extends longitudinally back through the rotatable tubular element, the stem portion carrying electrical connections to permit connection of the active electrode to an electrosurgical generator when in use.
11. An electrosurgical end effector according to any of the preceding claims, wherein the insulative carrier is formed from ceramic.
12. An electrosurgical end effector according to any of the preceding claims, wherein the rotary shaver arrangement further comprises an insulative tube that concentrically surrounds the rotatable tubular element, and has an open end such that the rotatable tubular element projects therefrom.
13. An cicctrosurgical end effector according to any of the preceding claims, wherein the interior of the rotatable tubular element in use acts as a suction lumen to permit the aspiration of cutting debris during use.
14. An cicctrosurgical instrument, comprising: a hand-piece; one or more user-operable buttons on the handpiece that control the instrument to operate, and an operative shaft, having RF electrical connections, and drive componentry for an end effector, the electrosurgical instrument further comprising an end effector according to any of the preceding claims, the rotary shaver arrangement being operably connected to the drive componentry to drive the rotary shaver to operate in use, and the active electrode being connected to the RF electrical connections.
15. An electrosurgical system, comprising: an RF electrosurgical generator; a suction source; and an electrosurgical instrument according to claim 14, the arrangement being such that in use the RF electrosurgical generator supplies an RF coagulation or ablation signal via the RF electrical connections to the active electrode, to permit tissue coagulation or ablation of the same tissue that is being cut by the rotary shaver arrangement.