DE102017007732A1 - Surgical instrument for flexible endoscope - Google Patents

Abstract

The invention relates to a surgical instrument for insertion into a flexible endoscope with a tubular work shaft. This comprises at least one, along its length extending instrument channel having a proximal and a distal end. The longitudinally slidable surgical instrument in the instrument channel is adapted to couple with an electrical waveform generator and to receive an electrical waveform. The distal end of the surgical instrument is formed with a cutting tool, wherein the cutting tool spreads on and / or after emerging from the distal end of the instrument channel of the flexible endoscope.

Description

The invention relates to a surgical instrument for insertion into a flexible endoscope according to the preamble of claim 1. The cutting tool disposed at the distal end of the surgical instrument expands upon and / or after exiting the distal end of the instrument channel of the flexible endoscope.

State of the art

Electrical surgical instruments for resection are known in the prior art. To resect this high-frequency alternating current is passed through the appropriate instrument through the body part to be treated in order to specifically damage or cut the tissue in question (high-frequency surgery, HF surgery). The biological tissue is cut, coagulated and / or vaporized. Such instruments for resection are used in urology or gynecology to remove pathological or excess tissue by vaporization, for example, in the transurethral resection of the prostate in a benign prostatic hyperplasia. A high-frequency voltage is applied to the instrument functioning as an electrode, which is generated by means of suitable high-frequency generators and supplied to the working part of the electrode via corresponding feeds, wherein the electrodes can be operated monopolar or bipolar depending on the training. The localized current density in the bipolar electrode causes a rapid heating of the tissue surrounding the electrode tip / s with consecutive vaporization of the tissue water or a rinsing fluid surrounding the tissue. A thin gas layer (vapor cushion) forms around the tip of the electrode, which can be ionized at a sufficiently high voltage (plasma ignition) to form a constant plasma. The energy of the plasma is transferred, for example, to the cells of the prostate tissue and leads to its localized vaporization.

Such surgical instruments can be used via an endoscope with working channel. Thus, for example, a urological resectoscope is known from the prior art, which comprises a rigid tube with a plurality of channels. This z. B. through a channel light in the interior of the body, for example, in the bladder, passed. Another channel, an instrument channel, can accommodate surgical instruments, such as performing treatments or taking tissue samples. Usually, the largest channel serves as a rinsing and suction device in order to be able to empty and fill the relevant organ, for example the bladder, during observation.

Surgery by means of such large-lumen, rigid surgical instruments is an operative procedure for the patient which requires general anesthesia or at least spinal anesthesia. Usually such interventions, such. Prostate resections, as part of a hospital stay. In addition, there is an increased risk of organ injury and bleeding when inserted through the respective anatomical access routes and when handling the large lumen, rigid surgical instruments.

The object of the present invention is therefore to provide a subject to high frequency current surgical instrument for insertion into a flexible endoscope (eg cystoscope), which is characterized in the leadership within the flexible endoscope by a smaller compared to conventional Resektoskopen space, creating the spatial Extension of the total resectoscope in the anatomical access path and in the organ concerned is significantly reduced.

Description of the invention

The invention relates, in a first subject matter, to a surgical instrument for insertion into a surgical flexible endoscope having a tubular working shaft which includes at least one instrument channel having a proximal and a distal end extending therealong for receiving at least one surgical instrument. The term "proximal" refers to the user's obvious part of the work, while the term "distal" designates the remote from the user part of the work. The surgical instrument is adapted to couple with an electrical waveform generator and receive an electrical waveform. Accordingly, the instrument can be supplied with high-frequency (HF) alternating current, wherein for resection, HF current is passed through the instrument through the body part to be treated and the instrument is operated as an electrical cutting tool. This allows a precise cut with low blood loss. Such known from the prior art surgical instruments are used for example for a urethral resection of a hypertrophied prostate. A distal end of the longitudinally displaceable in the instrument channel storable, inventive surgical instrument is formed with a cutting tool. Upon and / or after exiting the distal end of the instrument channel, the inventive cutting tool of the surgical instrument spreads. The term "spread" is thereby a State change of the cutting tool in the and / or after the exit understood, whereby the cutting tool as a whole or individual parts thereof relative to each other with respect to the longitudinal axis of the instrument predominantly in the lateral direction (laterally) as far as possible from each other. As a result, after this change of state, the cutting tool is in a "working position" and can be used to electrically cut and coagulate the tissue of interest. The cutting tool preferably has a Y-shaped configuration in the "working position". By spreading the cutting tool can thus be transferred from a "rest position" in a "working position", wherein the small spatial extent of the cutting tool laterally relative to the diameter of the instrument channel in the rest position advantageously allows the instrument in a flexible endoscope with a in the To use compared to conventional Resektoskopen significantly smaller dimensioned work. The surgical instrument according to the invention advantageously allows the use of endoscopes with a smaller working diameter compared to resectoscopes, wherein the endoscopes are additionally flexible and thus better adapted to the anatomy. Thus, the risks to the patient with respect to injury to surrounding tissues and bleeding during insertion of the endoscope and handling are minimized. For example, when using a flexible, reduced diameter cystoscope, work on the prostate can be done on an outpatient basis as part of benign prostatic hyperplasia under local anesthesia, and inpatient care is not required. In particular, with this type of intervention can be avoided by the use of the instrument according to the invention a postoperative disorder of sexual function. Advantageously, the total intervention time is significantly reduced due to the only local anesthesia and the much lower trauma to the patient.

In an advantageous embodiment, the cutting tool of the surgical instrument can spread open by spring force, either upon exiting and / or after exiting the distal end of the instrument channel. The cutting tool is thus designed as a spring, wherein a spring is a technical component is understood, which is used to store forces. The cutting tool is accordingly in the instrument channel in a tensioned state (as a carrier of potential energy) and in and / or after the exit, the cutting tool is relaxed. Preferably, the cutting tool is designed as a leg spring or as a torsion spring. A leg spring is a wound spring with protruding, preferably straight ends (legs). A torsion spring is a largely rod-shaped spring, wherein the spring action is achieved by rotating the rod. Advantageously, a designed as a spring cutting tool is characterized by simple production and low production costs. For spreading of such a cutting tool no separate guides and actuating means are required, by means of which the spreading of the cutting tool or individual components thereof is controlled. Also, such a cutting tool can be dimensioned in a simple manner according to the surgical application area; the space required for additional guides and actuating means can be saved.

In an advantageous development of the instrument, the spreading of the cutting tool can be controlled by a guide channel, in which the instrument with the distal cutting tool is movably storable and which in turn is arranged longitudinally displaceable in the instrument channel. As a result of the relative movement of the cutting tool relative to the guide channel, it can be present in an expanded form (cutting tool is not in the guide channel) or in a non-spread form (cutting tool is in the guide channel).

In an advantageous development of the instrument, the cutting tool can be connected to a guide and an actuator for controlling the spreading. About the guide and the associated operation, the user can control the spreading of the cutting tool, for example via a pull or push mechanism. Such a trained instrument allows precise and needs-adapted control of the cutting tool or parts thereof by the user.

In a further embodiment, the cutting tool may be formed as at least two-arm arrangement of needle electrodes. In the expanded state, a cutting tool formed with two arms may for example assume a rod-shaped form, the first and second needle electrodes being connected at their proximal end to one another and at the same time to the cutting tool further proximal part of the instrument, the cutting tool carrier adjacent to the cutting tool , A needle electrode is understood to be a wire which is coated to the tip with an insulating material. In the case of a monopolar needle electrode, a corresponding reference electrode must be provided. A bipolar needle electrode usually comprises at least two mutually insulated wires in a cylinder; the current flows between the wires. The arrangement of the needle electrodes at the distal end of the instrument can the respective operating area be customized. For example, for a prostate resection, a cutting tool having a two-arm array of needle electrodes may be selected in which the first and second electrodes are aligned, whereby the incision and resection of the organ disposed about the anatomical access path can occur simultaneously at two locations. For the treatment of an organ to be resected only in certain areas, a different arrangement, for example in the U- or V-shape or, in the case of a required comprehensive resection with multiple incisions, a star-shaped arrangement can be selected accordingly. Such a trained cutting tool can be dimensioned small according to the operating area in the resting state, so that it can easily insert into an instrument channel of the work of a flexible endoscope and can be moved in this to reach the working position. During and / or after spreading, the expansion required for the use of the cutting tool can be achieved in a simple manner predominantly laterally, but also distally relative to the instrument channel.

In a preferred development, the cutting tool can be designed as a three-arm arrangement of needle electrodes. Particularly preferably, the cutting tool can be designed as a Y-shaped arrangement of needle electrodes. Such a cutting tool is dimensioned according to the operating area at rest low (see above), so that it can easily insert into an instrument channel of the work of a flexible endoscope and can move distally in this to reach the working position. The extension of the needle electrodes laterally can take place in three different directions, wherein the adjacent needle electrodes can be arranged, for example, each at an angle of 120 ° to each other. A three-arm cutting tool thus combines the advantages of a space-saving storage in the instrument channel in the rest position with a long reach in the working position, whereby the surgical procedure can be performed comprehensive, gentle and time-saving. For example, in a prostate resection, under constant visual control, the organ can be incised and resected at three sites simultaneously.

In a preferred embodiment, a point of connection of the needle electrodes when moving the cutting tool to the distal end of the instrument channel may form the distal-most end of the surgical instrument. The connection point designates the point of the cutting tool to which, for example, the proximal end of the first needle electrode is connected to the proximal end of the second needle electrode and, at the same time, to the cutting tool carrier, ie the section of the instrument according to the invention located proximally of the cutting tool. Such a trained cutting tool remains in a largely non-spread state until it completely exits the instrument channel. As a result of the orientation to the proximal of the potentially pointed, distal ends of the needle electrodes during the displacement of the instrument distal to the surgical field, the instrument can advantageously also advance distally in a largely flexible instrument channel of a flexible endoscope. After the complete exit of the cutting tool from the instrument channel, the needle electrodes can spread laterally, for example by spring force from the rest position into a working position with maximum expansion. To return the instrument to the instrument channel after completion of the surgical procedure, the cutting tool can be retracted by the user back into the instrument channel. The spring formed by the electrode arms and the connection point is chosen in terms of their spring force F that on the one hand in the and / or after the escape a "passive" spreading in the untensioned working state is possible and on the other hand, the electrode arms for returning to the instrument channel are readily bendable in the direction opposite to the rest state of the cutting tool. Such an instrument is characterized by a simple construction and low production costs, which is particularly advantageous because it is preferably a one-off, i.e. one-off, tool. patient-specific, use is.

In the opposite case, namely when the distal tips of the needle electrodes are located farther distally than the point of connection during advancement, a slight curvature of the tips medially, i. in the direction of the central axis of the instrument, allow trouble-free advancement of the instrument in the instrument channel. Such a trained cutting tool can be withdrawn after completion of the surgical procedure in a simple manner in the instrument channel and, if necessary, pushed out of this again. This embodiment can be used especially for reusable instruments.

In a particularly preferred development, the cutting tool as a torsion spring (V-spring) or in particular as a torsion spring with two, connected by a spring body spring legs may be formed, the leg position is 180 ° in the tensioned state, and in the working state up to 0/360 °. Preferably, it is a torsion spring with a number of turns between 0.5 to 3. The spring body can be advantageously designed as a substantially U-shaped arc, wherein the spring legs emerge from the bow legs. A trained as a torsion spring cutting tool is exposed during the return from the working state in the working channel of a flexible endoscope deformation, which is lasting when in the reverse (directed against the winding direction) load of the leg spring, the bending stress exceeds the allowable value of the strain limit. Conveniently, spring stiffness and spring material are thus chosen so that, for example, an array of needle electrodes spreads after exiting the instrument channel and after completion of the surgical procedure, such as a prostate resection, traceable back through the instrument channel, the arrangement is thus flexible in both directions.

In a further alternative embodiment, the cutting tool may be formed as a helical spring. In this case, the spring expands during and / or after exiting the instrument channel mainly in the lateral, but also in the distal direction, based on the longitudinal axis of the instrument. A trained as a spiral spring cutting tool is characterized by ease of use: after spreading into the working state, the coil spring can be rotated by the user along the longitudinal axis of the cutting tool carrier in the instrument channel to achieve the corresponding surgical regions optimally.

In an advantageous development, the cutting tool may comprise a material with spring properties selected from the group consisting of a metal and a metal alloy. Particularly advantageously, the cutting tool may comprise spring steel, stainless steel and / or platinum-iridium alloys. Here, a spring steel is understood to mean a steel which has a higher strength compared to other steels.

In a further advantageous embodiment, the diameter of a circle, which is defined by a circular line connecting the distal ends of the cutting tool spread in the working state, can be larger by a factor of 1.25 to 4 than a diameter of a distal portion of the flexible endoscope, particularly preferably a factor of 1.45 to 3. By means of such a dimensioned cutting tool, the treated tissue can be reached via narrow access paths and, at the same time, a resection area located deeper in the tissue can be achieved.

In a preferred embodiment, the cutting tool can be rotated about its longitudinal axis by means of an actuator arranged at a proximal end of the surgical instrument. While the manual rotation of the resectoscope with the instrument located in the instrument channel of the work by pronation (inversion) and supination (outward rotation) of the instrument-guiding hand of the surgeon (user) allows rotation of the cutting tool, the rotation over an additional operation can advantageously a To enable fine adjustment of the cutting tool in the operating area. This is particularly advantageous if, for example, a two-arm cutting tool is used to resect a large area around the cutting tool, e.g. a prostate, should be used.

In an advantageous development, the instrument comprising the cutting tool can be designed as a bipolar electrode. For example, an instrument having a cutting tool configured as a two-armed needle electrode may be configured to flow current from one needle electrode to the other. Such arrangements are known, for example, for bipolar alligator forceps, e.g. to be used in laparoscopic surgery. Due to the close spatial arrangement of the electrodes, vaporization of the tissue water or of a rinsing fluid surrounding the tissue can be achieved in a narrowly defined area; A thin gas layer (plasma pocket) forms around the electrodes, which grows with energy input and forms a larger gas bubble with high-energy ions. A plasma vaporization is particularly suitable for the resection of the prostate.

In a further embodiment, the instrument displaceably arranged in a guide channel may comprise a cutting tool which is designed as an active electrode, wherein the guide channel may be formed as a return electrode at least in one area. This configuration can be used, for example, in the case where the cutting tool is formed as a helical spring. The coil spring can be moved via a guide channel to the tip of the instrument channel, wherein the instrument is movably mounted with the distal cutting tool in the guide channel. By the relative movement of the cutting tool and guide channel, for example via a proximally arranged actuator, the user can push out the trained as a spiral spring cutting tool from the guide channel and the corresponding instrument channel, for example, the guide channel can be pushed only to the distal end portion of the instrument channel, while the coil spring can emerge completely from this. The close spatial proximity between spiral spring and Return electrode allows the generation of plasma with a largely low energy input and thus precise operations with little damage to surrounding tissues.

In a second subject matter, the invention relates to a surgical endoscope comprising the surgical instrument described above, wherein the working shaft of the surgical endoscope, in which the surgical instrument according to the invention is introduced via the instrument channel, can have at least one bendable region along its longitudinal axis. The work is thus preferably such that you can bend it at least in a partial area. Such a designed endoscope allows a further reduction of the traumatic load on the patient during insertion of the flexible endoscope and during an intervention, since the work of the anatomical feeders and the structures in the operating area compared to rigid equipment can better adapt. In this case, a conventional flexible endoscope, for example a cystoscope, is designed such that the user can control the at least one assignable region with regard to its bending (flexion or deflection). For example, the use of a bendable cystoscope allows complete inspection of the bladder, since the flexion or deflection of the work can optimally align both the light source and the optic located therein.

In a preferred embodiment of the endoscope into which the instrument according to the invention can be inserted, the working shaft can be bendable along its longitudinal axis over the entire region. In particular, for operations on organs with long, small-sized anatomical additions, such as urethra (urethra), or ureter (ureter), a far-reaching flexibility of advantage with respect to a gentle, largely atraumatic surgical technique.

In an advantageous development, the surgical flexible endoscope in which the instrument according to the invention can be inserted may be a laryngoscope, nephroscope, sinusoidal, ureterorenoscope, cystoscope, hysteroscope, or otoscope. The corresponding surgical endoscopes can be present both as conventional, rigid devices, as well as flexible devices. Advantageously, the instrument according to the invention can be used due to its at rest only small distal diameter in comparison to conventional resectoscopes only small-sized, flexible surgical endoscopes, which are used for operations in anatomically difficult to access surgical areas used. Advantageously, by using a flexible endoscope access to the kidney (nephroscope, Ureterorensokop), to the ureters (Ureteroskop), to the sinuses (Sinuskop) can be significantly facilitated.

list of figures

• 1A bis 1C zeigen eine schräg seitliche, perspektivische Ansicht des distalen Endes des Arbeitsschafts eines flexiblen Endoskops, in welchem das erfindungsgemäße chirurgische Instrument geführt ist, dessen Schneidwerkzeug als drei-armige Anordnung von Nadelelektroden ausgebildet ist.
• 2 zeigt die korrespondierende Ansicht des distalen Endes des Arbeitsschafts eines flexiblen Endoskops, wobei das Schneidwerkzeug des chirurgischen Instruments als spiralförmige Feder ausgebildet ist.

Hereinafter, by way of example and not limitation, certain particular embodiments of the invention will be described with reference to the accompanying drawings. The particular embodiments are merely illustrative of the general inventive concept, but do not limit the invention.

• 1A to 1C show a diagonal perspective view of the distal end of the work of a flexible endoscope in which the surgical instrument according to the invention is performed, the cutting tool is designed as a three-arm arrangement of needle electrodes.
• 2 shows the corresponding view of the distal end of the work of a flexible endoscope, wherein the cutting tool of the surgical instrument is formed as a helical spring.

1A to 1C show an obliquely lateral, perspective view of the distal end of a flexible endoscope with a working shaft ( 1 ), which with an instrument channel ( 2 ) is trained. The instrument channel is shown at about 12:00 clock and runs along the longitudinal extent of the work over its entire length from the proximal ( 3 , left image side), ie the user facing, to the distal (4, right side of the image), ie the user facing away from the end. In the work shaft are further arranged a distal lens ( 5 ), which focuses the image of the corresponding organ and by means of the proximal of the lens ( 5 ), to these subsequent fiber bundles to the proximally located eyepiece (not shown) passes. The area of interest can be determined by means of two fiber optic light guides ( 6 ) are illuminated; the light guides ( 6 ) direct the light from an external light source (not shown) into the area in question. The tip of the workpiece is approximately hemispherical in shape to avoid sharp corners and edges and to minimize the risk of organ injury and bleeding during insertion and handling. 1A shows the distal end of the instrument according to the invention with a cutting tool ( 7 ) in the instrument channel ( 2 ). The cutting tool ( 7 ) is a three-arm needle electrode ( 9 ), wherein in 1A only two arms of the needle electrode ( 9 ), which on the cutting tool carrier ( 8th ) and whose distal ends are still in the instrument channel ( 2 ) are located. The connection point ( 10 ) which passes through the proximal ends of the three needle electrodes and the distal end of the cutting tool carrier (FIG. 8th ) is formed in the configuration shown before the complete exit of the cutting tool ( 7 ) from the instrument channel ( 2 ) the distal end of the cutting tool ( 7 ) of the surgical instrument. The in 1A right-pointing arrow indicates forward movement of the instrument ( 7 ) in the instrument channel ( 2 ) of the workforce ( 1 ). 1B shows the state change of the cutting tool ( 7 ) after the complete exit of the cutting tool ( 7 ) from the instrument channel ( 2 ) by spreading (dashed arrows). The three needle electrodes move from a tensioned rest position of the cutting tool ( 7 ) in the instrument channel ( 2 ) relative to the connection point ( 10 ) or the longitudinal axis of the instrument ( 7 ) distally and laterally. In 1C is the cutting tool ( 7 ) in the fully spread working position. The needle electrodes are connected to each other and to the cutting tool carrier ( 8th ) at the connection point ( 10 ) connected. To prevent injuries to organs by spreading the cutting tool ( 7 ), the alignment of the cutting tool ( 7 ) expediently under visual control either in a hollow organ, which is dimensioned larger than the cutting tool in its maximum lateral extent, or in a correspondingly dimensioned anatomical feed, which is connected to the organ to be treated. In 1C is a corresponding positioning of the cutting tool ( 7 ) in a prostate to be resected ( 11 shown); the three-armed needle electrode ( 9 ) incised the prostate ( 11 ) starting from the urethra ( 12 ) in three different places. In a cutting tool designed as a bipolar electrode ( 7 ) can generate localized plasma, thus gently and precisely removing the tissue.

2 shows a helical spring ( 13 ) formed cutting tool ( 7 ) in the spread state after complete emergence from the instrument channel ( 2 ). The tensioned at rest in the instrument channel ( 2 ) movably mounted spiral spring ( 13 ) can already be seen on exiting the instrument channel ( 2 ) partially spread, depending on the spring constant.

The spiral spring shown ( 13 ) can be rotated by means of an actuation and thus enables a precise alignment of the cutting tool relative to the organ to be treated. Since that as a spiral spring ( 13 ) formed cutting tool ( 7 ) can already spread significantly on emergence, is advantageous also the size of the cutting tool with respect to the tissue to be treated by the user flexibly adjustable and can for example be changed during the operation.

LIST OF REFERENCE NUMBERS

1

A working shaft

2

instrument channel

3

proximal end of work

4

distal end of the work

5

distal lens

6

fiber optic light guide

7

Cutting tool at the distal end of the surgical instrument

8th

Cutting tool carrier

9

needle electrode

10

junction

11

prostate

12

urethra

13

spiral spring

Claims (13)

Surgical instrument for insertion into an endoscope, preferably a flexible endoscope, comprising a tubular work shaft comprising at least one instrument channel extending at the length of the endoscope and having at least one proximal and one distal end for receiving at least one surgical instrument, the surgical instrument thereto adapted to couple with an electrical waveform generator and receive an electrical waveform, wherein a distal end of the longitudinally displaceable in the instrument channel storable surgical instrument is formed with a cutting tool, characterized in that the cutting tool at and / or after exiting the distal End of the instrument channel of the surgical endoscope spreads. Surgical instrument according to the Claim 1 , wherein the cutting tool spreads by spring force. Surgical instrument according to Claim 1 wherein the cutting tool is connected to a guide and an actuator for controlling the spreading. Surgical instrument according to one of the preceding claims, wherein the cutting tool is formed as at least two-arm arrangement of needle electrodes. Surgical instrument according to one of the preceding claims, wherein the Cutting tool is designed as a three-arm arrangement of needle electrodes. Surgical instrument according to one of Claims 4 or 5 wherein a point of connection of the needle electrodes as the cutting tool is displaced to the distal end of the instrument channel forms the most distal end of the instrument. Surgical instrument according to Claim 2 , wherein the cutting tool is formed as a helical spring. Surgical instrument according to one of the preceding claims, wherein the cutting tool can be rotated about its longitudinal axis by means of an actuator arranged at a proximal end of the surgical instrument. Surgical instrument according to one of the preceding claims, wherein the cutting tool is formed as a bipolar electrode. Surgical instrument according to one of the preceding claims, wherein the cutting tool is formed as an active electrode, and wherein the instrument is displaceable in a guide channel, wherein the guide channel is formed at least in one area as a return electrode. A surgical endoscope comprising the surgical instrument according to any one of the preceding claims, wherein the working shaft of the surgical endoscope has at least one bendable region along its longitudinal axis. Surgical endoscope according to Claim 11 in that the working shaft of the surgical endoscope is bendable along its longitudinal axis over the entire area. Surgical endoscope according to one of Claims 11 or 12 wherein the surgical endoscope is a laryngoscope, nephroscope, sinus, ureterorenoscope, cystoscope, hysteroscope, or otoscope.

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