US-20260123981-A1 - ELECTROSURGICAL INSTRUMENT AND ELECTROSURGICAL APPARATUS

US20260123981A1US 20260123981 A1US20260123981 A1US 20260123981A1US-20260123981-A1

Abstract

Various aspects provide an electrosurgical instrument for sealing and cutting tissue, comprising an instrument shaft with a transmission line for microwave electromagnetic energy. The instrument includes a first and second jaw with respective surfaces, first and second electrode for emitting microwave energy, an isolating portion to electrically separate the electrodes, a cutting device. The jaws can move between an open position for tissue insertion and a closed position to clamp tissue. Both electrodes are located on the first jaw, with sections exposed on the first surface to form a first and second sealing area separated by a gap. This gap ensures the tissue between the sealing areas is not sealed during microwave emission. The sealing areas are designed to seal tissue on either side of the gap. The cutting device operates along a cutting line on the first surface, positioned over the gap, to cut tissue in the closed position.

Inventors

George Christian ULLRICH
Steven Thomas
Louis TURNER
Warren Jones
Christopher Paul Hancock
Duncan James Foster FITZSIMONS

Assignees

CREO MEDICAL LIMITED

Dates

Publication Date: 20260507
Application Date: 20230906
Priority Date: 20220923

Claims (20)

1 . An electrosurgical instrument for sealing and cutting tissue, comprising: an instrument shaft comprising a transmission line for conveying microwave electromagnetic energy; a first jaw attached to the instrument shaft and including a first surface, a second jaw attached to the instrument shaft and including a second surface, a first electrode for emitting microwave electromagnetic energy, a second electrode for emitting microwave electromagnetic energy, a first isolating portion electrically isolating the first electrode from the second electrode, a second isolating portion, and a cutting device for cutting the tissue, and wherein the first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp tissue therebetween, wherein the first electrode and the second electrode are arranged on the first jaw, wherein sections of the first and second electrodes are exposed on the first surface to define a first sealing area and a second sealing area on the first surface, wherein the first sealing area is spaced from the second sealing area to form a gap therebetween on the first surface so that the tissue between the first sealing area and the second sealing area is not sealed upon the emission of the microwave electromagnetic energy, wherein the first and second sealing areas are configured to seal the tissue on either side of the gap using the emitted microwave electromagnetic energy, wherein the cutting device is effective along a cutting line on the first surface to cut the tissue in the closed position, the cutting line being positioned on the gap, wherein the cutting device includes a radiofrequency electrode arranged on the cutting line, and wherein the second isolating portion electrically isolates the radiofrequency electrode from the first electrode.
2 . The electrosurgical instrument according to claim 1 , wherein the second electrode covers the first electrode on the side of the first electrode facing away from the first surface or wherein the first isolating portion is arranged between the first electrode and the second electrode.
3 . The electrosurgical instrument according to claim 1 , wherein portions of the first electrode or the second electrode are plate-shaped and respectively include end faces, wherein the end faces form the exposed sections, wherein, in a cross-sectional view of the first jaw, the portions of the first electrode or the second electrode are substantially U-shaped or V-shaped.
4 . The electrosurgical instrument according to claim 1 , wherein the exposed sections of the first electrode and the second electrode: at least partially extend parallel to each other, each include two straight portions that extend parallel to each other, or each form a loop, optionally a U-shape in a top view of the first jaw.
5 . The electrosurgical instrument according to claim 4 , wherein, in the closed position, the cutting line is arranged: between the straight portions of the exposed sections of the first electrode or within the loop of the exposed section of the first electrode.
6 . The electrosurgical instrument according to claim 1 , wherein the first sealing area and the second sealing area define an angle of less than 180° with respect to each other.
7 . (canceled)
8 . The electrosurgical instrument of claim 1 , wherein the radiofrequency electrode includes a ridge protruding from the second isolating portion.
9 . An electrosurgical instrument for sealing and cutting tissue, comprising: an instrument shaft comprising a transmission line for conveying microwave electromagnetic energy; a first jaw attached to the instrument shaft and including a first surface, a second jaw attached to the instrument shaft and including a second surface, a first electrode for emitting microwave electromagnetic energy, a second electrode for emitting microwave electromagnetic energy, a first isolating portion electrically isolating the first electrode from the second electrode, and a cutting device for cutting the tissue, and wherein the first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp tissue therebetween, wherein the first electrode and the second electrode are arranged on the first jaw, wherein sections of the first and second electrodes are exposed on the first surface to define a first sealing area and a second sealing area on the first surface, wherein the first sealing area is spaced from the second sealing area to form a gap therebetween on the first surface so that the tissue between the first sealing area and the second sealing area is not sealed upon the emission of the microwave electromagnetic energy, wherein the first and second sealing areas are configured to seal the tissue on either side of the gap using the emitted microwave electromagnetic energy, wherein the cutting device is effective along a cutting line on the first surface to cut the tissue in the closed position, the cutting line being positioned on the gap, wherein the cutting device includes a radiofrequency electrode exposed on the second surface, and wherein the electrosurgical instrument further comprises a second isolating portion arranged on the first jaw so that, in the closed position, the second isolating portion electrically isolates the radiofrequency electrode from the first electrode.
10 . The electrosurgical instrument of claim 9 , wherein the second isolating portion is made from silicon.
11 . The electrosurgical instrument according to claim 1 , wherein the second jaw includes a first arm movable with respect to the second surface, wherein the second jaw includes an opening through which the first arm can be moved.
12 . The electrosurgical instrument according to claim 11 , wherein the radiofrequency electrode is arranged on the first arm.
13 . The electrosurgical instrument according to claim 11 , wherein the first arm includes a third isolating portion which is in contact with the radiofrequency electrode in a press position of the first arm, in which the first arm and the first surface are brought together to cut tissue therebetween.
14 . The electrosurgical instrument according to claim 11 , wherein the second jaw includes a fourth isolating portion which covers the opening and is flexible across the opening so that the radiofrequency electrode is configured to deform the fourth isolating portion in the closed position or the first arm deforms the fourth isolating portion in a press position of the first arm, in which the first arm and the first surface are brought together to cut tissue therebetween, wherein optionally the fourth isolating portion is made from silicon.
15 . The electrosurgical instrument according to claim 8 , wherein the second jaw includes a protruding portion and a recessed portion, wherein, in the closed position, the protruding portion is in contact with the first surface and the recessed portion is spaced from the radiofrequency electrode, and wherein the protruding portion is flexible so that the second jaw can be further moved towards the first surface relative to the closed position so that the recessed portion can be moved closer towards the radiofrequency electrode.
16 . The electrosurgical instrument according to claim 1 , further comprising a third electrode for emitting microwave energy and exposed on the second surface or a fourth electrode for emitting microwave energy and exposed on the second surface.
17 . The electrosurgical instrument according to claim 16 , wherein the first electrode is electrically connected to the third electrode or the second electrode is electrically connected to the fourth electrode, or the transmission line comprises a first coaxial cable, which is connected to the first electrode and the second electrode, and a second coaxial cable, which is connected to the third electrode and the fourth electrode, wherein optionally, in the closed position, a first point of contact of the first coaxial cable with the first electrode and the second electrode is laterally offset along a direction of extension of the first jaw and the second jaw compared to a second point of contact of the second coaxial cable with the third electrode and the fourth electrode.
18 - 19 . (canceled)
20 . An electrosurgical apparatus for sealing and cutting tissue, comprising: a generator unit for generating radiofrequency or microwave electromagnetic energy, and the electrosurgical instrument according to claim 1 , wherein the transmission line conveys the radiofrequency or microwave electromagnetic energy from the generator unit to the first electrode, the second electrode or the cutting device.
21 . The electrosurgical apparatus according to claim 20 , wherein the generator unit is configured to simultaneously generate microwave electromagnetic energy of a first frequency and microwave electromagnetic energy of a second frequency.

Description

FIELD OF THE INVENTION The invention relates to an electrosurgical instrument for sealing and cutting tissue. The electrosurgical instrument is configured to grasp biological tissue and deliver microwave energy into the grasped tissue to seal the tissue by coagulation or cauterisation. The electrosurgical instrument may be used to apply pressure to close one or more blood vessels before applying electromagnetic radiation (preferably microwave energy) to seal the blood vessel(s). The electrosurgical instrument may also be arranged to cut, e.g. separate or divide, the vessel or surrounding tissue after coagulation or sealing, e.g. using radiofrequency (RF) energy and/or a mechanical cutting element, such as a blade. The invention may be applied to a vessel sealer for use in laparoscopic surgery or open surgery as well as to an endoscopic instrument. The invention also relates to an electrosurgical apparatus for sealing and cutting tissue which comprises a generator unit for generating radiofrequency and/or microwave electromagnetic energy, and the electrosurgical instrument. BACKGROUND TO THE INVENTION Electrosurgical instruments for delivering heat energy into grasped biological tissue are known. For example, it is known to deliver microwave energy from a bipolar electrode arrangement in the jaws of a forceps. The microwave energy may be used to seal a vessel by thermal denaturation of extracellular matrix proteins (e.g. collagen) within the vessel wall. The heat energy may also cauterise the grasped tissue and facilitate coagulation. Such devices typically find application on the end of minimally invasive surgical laparoscopic tools but can equally find use in other clinical procedural areas such as gynaecology, endourology, gastrointestinal surgery, ENT procedures, or endoscopic procedures. Depending on the context of use, these devices can have differing physical construction, size, scale and complexity. For example, a gastrointestinal instrument might be nominally of 3 mm diameter mounted on to the end of a very long flexible shaft. In contrast, a laparoscopic instrument may be used on the end of an industry standard nominal 5 mm or 10 mm diameter rigid or steerable steel shaft. U.S. Pat. No. 6,585,735 describes an endoscopic bipolar forceps in which the jaws of the forceps are arranged to conduct bipolar energy through the tissue held therebetween. EP 2 233 098 describes microwave forceps for sealing tissue in which the sealing surfaces of the jaws include one or more microwave antennas for radiating microwave energy into tissue grasped between the jaws of the forceps. WO 2015/097472 describes electrosurgical forceps in which one or more pairs of non-resonant unbalanced lossy transmission line structures are arranged on the inner surface of a pair of jaws. SUMMARY OF THE INVENTION At its most general, the present invention provides an electrosurgical instrument that can seal biological tissue, such as (blood) vessels, using a confined microwave field that can yield a well-defined seal location with low thermal margin. Moreover, the electrosurgical instruments may provide additional functionality, such as by a cutting device to enable fine tissue cutting and dissection to be performed. With these additional functions, fewer device interchanges may be needed during a procedure. The electrosurgical instruments disclosed herein may be used in any type of surgical procedure, but it is expected to find particular utility for non-invasive or minimally invasive procedures. For example, the device may be configured to be introduced to a treatment site through an instrument channel of a surgical scoping device, such as a laparoscope or an endoscope. According to a first aspect of the present invention, there is provided an electrosurgical instrument for sealing and cutting tissue which comprises an instrument shaft, a first jaw, a second jaw, a first electrode, a second electrode, a first isolating portion, and a cutting device. The instrument shaft comprises a coaxial transmission line for conveying microwave electromagnetic energy. The first jaw is attached to the instrument shaft and includes a first surface. The second jaw is attached to the instrument shaft and includes a second surface. The first isolating portion electrically isolates the first electrode from the second electrode. The cutting devise is configured to cut tissue. The first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp, hold and/or grasp tissue therebetween. The first electrode and the second electrode are arranged on the first jaw. Sections of the first and second electrodes are exposed on the first surface to define a first sealing area and a second sealing area on the first surface. The first sealing area is spaced from the second sealing area to fo