US-20260123980-A1 - ELECTROSURGICAL INSTRUMENT AND ELECTROSURGICAL APPARATUS

Abstract

Various aspects disclose an electrosurgical instrument designed for sealing or cutting tissue. The instrument features an instrument shaft with a transmission line to convey microwave or radiofrequency electromagnetic energy. It includes a first jaw with a first surface and a distal end face, and a second jaw with a second surface, both attached to the shaft. The instrument is equipped with first and second electrodes for emitting microwave or radiofrequency energy. A first isolating portion electrically separates the two electrodes. The jaws can move between an open position, allowing tissue insertion between the surfaces, and a closed position, clamping the tissue. The first and second electrodes are exposed on the first surface and distal end face. In the closed position, the second jaw covers the exposed electrodes on the first surface and distal end face, ensuring effective tissue engagement and energy application for surgical procedures.

Inventors

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

Assignees

• CREO MEDICAL LIMITED

Dates

Publication Date

20260507

Application Date

20230804

Priority Date

20220923

Claims (20)

1. 1 . An electrosurgical instrument for sealing or cutting tissue, comprising: an instrument shaft comprising a transmission line for conveying microwave electromagnetic energy or radiofrequency electromagnetic energy; a first jaw attached to the instrument shaft and including a first surface as well as a distal end face, a second jaw attached to the instrument shaft and including a second surface, a first electrode for emitting microwave electromagnetic energy or radiofrequency electromagnetic energy, and a second electrode for emitting microwave electromagnetic energy or radiofrequency electromagnetic energy, and a first isolating portion electrically isolating the first electrode from the second electrode, 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 exposed on the first surface and on the distal end face, and wherein, in the closed position, the second jaw covers the exposed first or second electrodes on the first surface and the distal end face.
2. 2 . The electrosurgical instrument according to claim 1 , wherein the second jaw includes an overhang portion protruding from the second surface, wherein the overhang portion covers the exposed first or second electrodes on the distal end face in the closed position.
3. 3 . The electrosurgical instrument according to claim 1 , further including a cutting device for cutting tissue in the closed position, wherein sections of the first and second electrodes that 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, 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, and 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.
4. 4 . The electrosurgical instrument according to claim 1 , wherein the second electrode covers the first electrode on a 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.
5. 5 . The electrosurgical instrument according to claim 3 , wherein portions of the first electrode or the second electrode 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.
6. 6 . The electrosurgical instrument according to claim 3 , wherein the sections of the first electrode and the second electrode that are exposed on the first surface at least partially extend parallel to each other, or each include two straight portions that extend parallel to each other.
7. 7 . The electrosurgical instrument according to claim 6 , wherein, in the closed position, the cutting line is arranged between the parallel extensions or the straight portions of the sections of the first electrode that are exposed on the first surface.
8. 8 . The electrosurgical instrument according to claim 1 , wherein sections of the first electrode that are exposed on the distal end face are spaced from sections of the second electrode that are exposed on the distal end face or from each other.
9. 9 . The electrosurgical instrument according to claim 1 , wherein the distal end face includes a single section of the first electrode that it exposed on the distal end face and a single section of the second electrode that is exposed on the distal end face.
10. 10 . The electrosurgical instrument according to claim 9 , wherein the exposed section of the first electrode on the distal end face or the exposed section of the second electrode on the distal end face form a connecting section connecting a first sealing area to a second sealing area.
11. 11 . The electrosurgical instrument according to claim 3 , wherein the first sealing area and the second sealing area define an angle of less than 180° with respect to each other.
12. 12 . The electrosurgical instrument according to claim 3 , further comprising a second isolating portion on the first jaw, wherein the cutting device includes a blade, and wherein the second isolating portion includes a groove in which the blade is movable.
13. 13 . The electrosurgical instrument according to claim 12 , wherein the groove is open at the distal end face so that the blade can be moved beyond the distal end face.
14. 14 . The electrosurgical instrument according to claim 13 , wherein the second isolating portion is exposed on the distal end face and the groove in the second isolating portion extends until all the distal end face.
15. 15 . The electrosurgical instrument according to claim 12 , wherein the groove ends before the distal end face.
16. 16 . The electrosurgical instrument according to claim 2 , further comprising a fluid feed configured to convey a fluid to the distal end face.
17. 17 . The electrosurgical instrument according to claim 16 , wherein the fluid feed comprises at least one port for outputting the fluid, wherein the port is arranged on the distal end face or a side surface of the overhang portion contacting the distal end face in the closed position.
18. 18 . The electrosurgical instrument according to claim 2 , wherein the second jaw includes a third isolating portion which is exposed on the second surface or the overhang portion, wherein optionally only the third isolating portion is in direct contact with the first jaw in closed position.
19. 19 . An electrosurgical apparatus for sealing and cutting tissue, comprising: a generator unit for generating radiofrequency or microwave electromagnetic energy, and the electrosurgical instrument according claim 1 , wherein the transmission line is configured to convey the radiofrequency or microwave electromagnetic energy from the generator unit to the first electrode, the second electrode or a cutting device.
20. 20 . The electrosurgical apparatus according to claim 19 , wherein the generator unit is configured to simultaneously or alternatingly generate microwave electromagnetic energy of a first frequency and radiofrequency electromagnetic energy of a third frequency.

Description

FIELD OF THE INVENTION The invention relates to an electrosurgical instrument for sealing and/or 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 cauterization. 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 before or 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 cauterize 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 gynecology, 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 various types of electrosurgical instruments that can enable fine tissue cutting and dissection to be performed on tissue. Moreover, the electrosurgical instruments may provide additional functionality, such as sealing biological tissue, such as (blood) vessels, using a confined microwave field that can yield a well-defined seal location with low thermal margin. 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 electrosurgical instruments 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/or cutting tissue which comprises an instrument shaft, a first jaw, a second jaw, a first electrode, a second electrode, and a first isolating portion. 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 as well as a distal end face. 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 first and/or second electrodes are configured to emit microwave and/or radiofrequency electromagnetic energy. 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 exposed on the first surface and on the distal end face. In the closed position, the second jaw covers sections of the first elect