BIPOLAR MAPPING SUCTION DEVICE

Abstract

The present invention relates to a suction instrument, more particularly a bipolar mapping suction instrument, for surgical purposes and to a system for suctioning fluids and tissue and for monitoring nerve tissue. The suction instrument comprises a cannula unit, which comprises an electrically conductive outer cannula tube, an electrically conductive inner cannula tube, and insulation. The electrically conductive inner cannula tube is electrically connected to a first pole of the bipolar electrical connection of the second interface. The electrically conductive inner cannula tube is arranged concentrically in the outer cannula tube which optionally can be insulated from the exterior. The electrically conductive inner cannula tube is mechanically connected to the handpiece and/or the first interface. The electrically conductive outer cannula tube is electrically connected to a second pole of the bipolar electrical connection of the second interface. The insulation is concentrically arranged between the outer cannula tube and the inner cannula tube. The insulation is configured to fully electrically isolate the outer cannula tube and the inner cannula tube in relation to one another.

Claims

1. A suction instrument for surgical purposes, the suction instrument comprising: a handpiece; a first interface configured to establish at least one fluid connection with an external suction device or rinsing device; and a second interface configured to establish a bipolar electrical connection with an external stimulation device; and a cannula unit extending from the handpiece in an axial direction and mechanically connected to the handpiece at a proximal end of the cannula unit, the cannula unit comprising: an electrically conductive inner cannula tube electrically connected to a first pole of the bipolar electrical connection of the second interface, concentrically arranged in an outer cannula tube and fluidly connected to the first interface; an electrically conductive outer cannula tube electrically connected to a second pole of the bipolar electrical connection of the second interface; and an insulation concentrically arranged between the outer cannula tube and the inner cannula tube and configured to fully electrically insulate the outer cannula tube and the inner cannula tube in relation to one another.

2. The suction instrument of claim 1, further comprising an illumination device comprising at least one of a light source and a light guide, wherein the light outlet is arranged on the handpiece or alternatively on the cannula unit and is configured to allow light to exit from the light guide or alternatively from the light source in the direction of a situs, wherein the light guide is configured to guide light emitted from the light source or alternatively from an external light source to the light outlet.

3. The suction instrument of claim 1, further comprising a tracking element configured to be detected by an external navigation device and fixedly or detachably mechanically connected to the handpiece or the cannula unit.

4. The suction instrument of claim 1, wherein at least one of the outer cannula tube, the inner cannula tube and the insulation are made biocompatible or bioinert.

5. The suction instrument of claim 1, wherein the cannula unit has an outer diameter of 1 millimeter (mm) to 15 mm.

6. The suction instrument of claim 1, wherein the cannula unit has a length of 10 centimeters (cm) to 40 cm.

7. The suction instrument of claim 1, wherein the cannula unit is straight or alternatively has a bend with an angle of 10° to 60° or with an angle of, 30° in a proximal region.

8. The suction instrument of claim 1, wherein the handpiece comprises a suction control opening which is fluidly connected to the inner cannula tube.

9. The suction instrument of claim 1, wherein the cannula unit is fixedly or detachably mechanically connected to the handpiece at the proximal end of the cannula unit.

10. The suction instrument of claim 1, further comprising a first controllable valve, wherein the inner cannula tube is fluidly connected to the external suction device by means of the first controllable valve and a first fluid connection of the first interface.

11. The suction instrument of claim 10, wherein the handpiece further comprises a first operating element which is configured to switch between a suction function of the external suction device and a rinsing function of the external rinsing device.

12. The suction instrument of claim 1, wherein the second interface comprises two connection pins for establishing a monopolar or bipolar connection.

13. The suction instrument of claim 1, wherein the handpiece further comprises a second operating element, wherein the second interface is further configured to establish a communicative connection of the second operating element with the external stimulation device, and wherein the second operating element is configured to switch between a monopolar operation and a bipolar operation.

14. A system for suctioning fluids and tissue and/or flushing the situs as well as for monitoring nerve tissue, the system comprising: the suction instrument for surgical purposes; at least one of a suction instrument and an rinsing device; at least one, conductive electrodes attachable to a patient in the vicinity of nerve tissue to be monitored; and an IOM system comprising a stimulation device and a monitoring device communicatively connected to the stimulation device, wherein at least one of the suction instrument and rinsing device is fluidly connected to the suction instrument by means of a fluid line by means of the first interface, wherein the stimulation device of the IOM system is electrically connected to the suction instrument in a monopolar or bipolar manner by means of a monopolar or bipolar connection by means of the second interface, wherein the stimulation device is configured to electrically stimulate tissue by means of at least one of the two cannula tubes, and wherein the monitoring device is electrically connected to the at least two conductive electrodes and is configured to either monitor a stimulus response recorded by the at least two conductive electrodes or to output it acoustically or visually to a user.

15. The system of claim 14 further comprising an impedance measurement device communicatively connected to the monitoring unit and configured to perform an impedance measurement.

16. The suction instrument of claim 4, wherein at least one of the outer cannula tube and the inner cannula tube are made of stainless steel.

17. The suction instrument of claim 4, wherein the insulation is made of plastic or polyamide.

18. The suction instrument of claim 10, further comprising a second controllable valve, wherein the inner cannula tube is fluidly connected to the external rinsing device by means of the second controllable valve and a second fluid connection of the first interface.

19. The suction instrument of claim 1, wherein the second interface comprises a bipolar cable for establishing the monopolar or bipolar electrical connection.

20. The suction instrument of claim 1, wherein the suction instrument is a bipolar mapping suction instrument for surgical purposes.

21. The system of claim 14, wherein at least one of the suction instrument and rinsing device is fluidly connected to the suction instrument by means of a semirigid tube.

22. The system of claim 14, wherein the stimulation device of the IOM system is electronically connected to the suction instrument by means of a monopolar or bipolar cable.

23. The system of claim 15, wherein the IOM system is configured to perform the impedance measurement, wherein complex resistances at different frequencies of tissue surrounding the tip of the cannula unit are measured for impedance measurement, and wherein the system is configured to determine and output to the user type of tissue based on the measured impedances.

24. The system of claim 14, wherein the suction instrument comprising: a handpiece; a first interface configured to establish at least one fluid connection with an external suction device or rinsing device; and a second interface configured to establish a bipolar electrical connection with an external stimulation device; and a cannula unit extending from the handpiece in an axial direction and mechanically connected to the handpiece at a proximal end of the cannula unit, the cannula unit comprising: an electrically conductive inner cannula tube electrically connected to a first pole of the bipolar electrical connection of the second interface, concentrically arranged in an outer cannula tube and fluidly connected to the first interface; an electrically conductive outer cannula tube electrically connected to a second pole of the bipolar electrical connection of the second interface; and an insulation concentrically arranged between the outer cannula tube and the inner cannula tube and configured to fully electrically insulate the outer cannula tube and the inner cannula tube in relation to one another.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0091] The present invention is explained in more detail below with reference to the embodiments indicated in the schematic figures of the drawing, wherein

[0092] FIG. 1 shows a schematic view of the suction instrument according to the first aspect of the present invention,

[0093] FIG. 2 shows an enlarged schematic view of the cannula unit of the suction instrument of FIG. 1,

[0094] FIG. 3 shows a schematic view of a further embodiment of the suction instrument according to the first aspect of the present invention,

[0095] FIG. 4 shows a schematic view of a further embodiment of the suction instrument according to the first aspect of the present invention,

[0096] FIG. 5 shows a schematic view of a further embodiment of the suction instrument according to the first aspect of the present invention, and

[0097] FIG. 6 shows a schematic view of the system according to the second aspect of the present invention.

[0098] The accompanying figures of the drawing are intended to provide a further understanding of the exemplary embodiments of the invention. The embodiments illustrate exemplary embodiments and, in connection with the description, serve to explain principles and concepts of the invention. Other embodiments and many of the advantages mentioned will be apparent with reference to the drawings. The elements of the drawings are not necessarily shown to scale with respect to each other.

[0099] In the figures of the drawing, elements, features and components, which are the same, have the same function and act in the same way, are each given the same reference numerals, unless otherwise stated.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0100] In FIG. 1, the suction instrument 1, in this case a bipolar mapping suction instrument, is schematically shown according to the first aspect of the present invention. The suction instrument 1 comprises a handpiece 2, a first interface 3, a second interface 4 and a cannula unit 5.

[0101] The handpiece 2 is ergonomically shaped and made of plastic (e.g., poyetheretherketone, PEEK, PC/ABS). A surgeon can take the handpiece 2 in his hand and guide the suction instrument 1 over it during a surgical procedure.

[0102] The first interface 3 is formed as a fluid-conducting coupling for a semirigid tube (not shown) at a proximal end of the handpiece 2. Both a suction instrument (not shown) and an rinsing device (not shown) can be fluidly connected to the first interface 3 by means of the semirigid tubing.

[0103] The second interface 4 is formed as two connector pins distally on a bottom surface of the handpiece 2, to which a bipolar cable (not shown) can be connected, and comprises a bipolar connection. A stimulation device (not shown) may be electrically connected to the second interface 4 by means of the bipolar cable, and may thus connected in a bipolar fashion. Alternatively, a monopolar cable may be connected to one of the connection pins.

[0104] The cannula unit 5 has its proximal end firmly mechanically connected to the handpiece 2. The cannula unit 5 extends towards a tip or distal end of the cannula unit 5. Thereby, the cannula unit 5 has an angulation in a proximal area of the cannula unit 5 of 30° downwards.

[0105] The exact structure of the cannula unit 5 is shown schematically in FIG. 2. The cannula unit 5 comprises an outer cannula tube 5.1, an inner cannula tube 5.2 and an insulation 5.3.

[0106] The outer cannula tube 5.1 is formed of stainless steel, and is detachably firmly mechanically connected to the handpiece 2 (e.g., screw connection, snap connection, etc.). The outer cannula tube extends from the handpiece 2 to the tip of the cannula unit 5. Furthermore, the outer cannula tube 5.1 is mechanically connected to the handpiece 2 and electrically connected to one pole of the bipolar connection of the second interface 4 and thus to the stimulation device by means of an electrical contact, for example a solder joint or weld, in the handpiece 2. Thus, the outer cannula tube 5.1, in particular at the tip of the cannula unit 5, can be used as an electrode for monopolar or bipolar stimulation of tissue by the stimulation device.

[0107] The inner cannula tube 5.2 is formed of stainless steel and extends concentrically to the outer cannula tube 5.1, with the inner cannula tube 5.2 extending from the tip of the cannula unit 5 to beyond a proximal end of the outer cannula tube 5.1 into the handpiece 2. The inner cannula tube 5.2 is mechanically connected to the handpiece 2 and electrically connected to the corresponding other pole of the bipolar connection of the second interface 4 and thus to the stimulation device by means of an electrical contact, for example a solder joint or weld, in the handpiece 2. Thus, the inner cannula tube 5.2 can be used as an electrode for monopolar or bipolar stimulation of tissue by the stimulation device.

[0108] Insulation 5.3 is formed as a tube of polyamide, and insulates the outer cannula tube 5.1 over its entire length from the inner cannula tube 5.2 extending concentrically therein, thereby preventing an electrical short circuit between the two cannula tubes 5.1, 5.2 and enabling bipolar stimulation of tissue by the control device.

[0109] The inner cannula tube 5.2 has a lumen 5.4 extending from the tip of the cannula unit 5 to a distal end of the inner cannula tube 5.2. The lumen 5.4 of the inner cannula tube 5.2 is mechanically connected within the handpiece 2 and thereby fluidly connected to the first interface 3 and thus to the suction device and the rinsing device. The interior of the handpiece 2 may be formed in two parts, such that a first cavity (not shown) is separated from a second cavity (not shown) by a partition (not shown) up to the beginning of the inner cannula tube 5.2. For example, the suction instrument may be fluidly connected to the first cavity, while the rinsing device may be fluidly connected to the second cavity. Through the suction instrument, a negative pressure or vacuum can thus be applied to the lumen 5.4 of the inner cannula tube 5.2, so that a suction effect is created at the tip of the cannula unit 5, with which fluids such as blood and tissue can be sucked out of the situs. Analogously, the rinsing device can thus convey a rinsing medium such as isotonic saline solution to the tip of the cannula unit 5 and the situs can be rinsed or moistened with it. The rinsing medium from the rinsing device can then be sucked out of the situs by the suction instrument at the tip of the cannula unit 5.

[0110] In FIG. 3, a further embodiment of the suction instrument 1 according to the first aspect of the present invention is schematically shown. The suction instrument 1 of FIG. 3 largely corresponds to the suction instrument 1 of FIG. 1. Therefore, only the differences are explained below.

[0111] Instead of two connection pins, the second interface 4 is configured here as a bipolar cable 4.1. The bipolar cable 4.1 has two sockets 4.2 or alternatively two plugs at its free end, which can be connected directly to an IOM system, more precisely to the stimulation device. The bipolar cable 4.1 is firmly integrated into the handpiece 2 and electrically connected to the outer cannula tube 5.1 and the inner cannula tube 5.2, respectively, by two electrical contacts 4.3 (e.g., soldered or welded joint).

[0112] In FIG. 4, a further embodiment of the suction instrument 1 according to the first aspect of the present invention is schematically shown. The suction instrument 1 of FIG. 4 largely corresponds to the suction instrument 1 of FIG. 1 and FIG. 3. Therefore, only the differences are explained below.

[0113] The first interface 3 and the second interface 4 are arranged here directly on the cannula unit 5 instead of on the handpiece 2, or are formed integrally/integrally therewith. The second interface 4 can be implemented either by two connection pins as shown or alternatively by a bipolar cable 4.1, as described for the embodiment in FIG. 3. In each case, only one of the two interfaces 3, 4 can also be arranged directly on the cannula unit 5 and the other of the two interfaces 3, 4 can be arranged on the handpiece 2 in accordance with the embodiment examples from FIG. 1 and FIG. 3.

[0114] In FIG. 5, a further embodiment of the suction instrument 1 according to the first aspect of the present invention is schematically shown. The suction instrument 1 of FIG. 5 largely corresponds to the suction instrument 1 of FIG. 1, FIG. 3 and FIG. 4. Therefore, only the differences are explained below.

[0115] The suction instrument 1 here further comprises an LED 6, a tracking element 7, a suction control opening 8, a first operating element 9.1 and a second operating element 9.2.

[0116] The LED 6 is integrated into the handpiece 2. The LED 6 can be switched on and off either directly on the handpiece 2 or by means of the stimulation device. The LED 6 can alternatively be connected to a light guide (not shown) that extends along the outer tube surface of the outer cannula tube 5.1, where it can illuminate the situs. The light guides transmit the light emitted from a light source or from the LED and illuminate the situs.

[0117] The tracking element 7 is arranged here at the proximal end of the handpiece 2.

[0118] Alternatively, it may also be arranged at the proximal end of the cannula unit 5. Exemplarily, the tracking element 7 here has three markers in the form of reflective spheres arranged in a predetermined unequal-sided triangle with respect to each other. The position and pose of the tracking element 7 can be determined by an external navigation device 40 with a stereo camera by triangulation. From this, the position and pose of the suction instrument 1 and in particular the tip of the cannula unit 5 can be displayed in registered image data of the patient.

[0119] The suction control opening 8 is arranged on an upper side of the handpiece 2 and is fluidly connected to the lumen 5.4 of the inner cannula tube 5.2 through fluid channels in the handpiece 2. The suction opening 8 can be closed with a thumb, which allows the suction effect at the tip of the cannula unit 5 to be controlled.

[0120] The first operating element 9.1 is configured as a switch and is arranged on the handpiece 2 or alternatively on the suction instrument or rinsing device (not shown) or alternatively on the fluid-conducting cable or alternatively on the cannula unit 5. By means of the first operating element 9.1, for example, a first controllable valve (not shown) as well as a second controllable valve (not shown), which can be arranged in the handpiece 2 preferably directly at the first interface 3, can be opened and closed in opposite directions. The first controllable valve can fluidly connect the lumen 5.4 of the inner cannula tube 5.2 with the first interface 3 and thereabove with the suction instrument. The second controllable valve can fluidly connect the lumen 5.4 of the inner cannula tube 5.2 to the first interface 3 and above to the rinsing device. If the first controllable valve is opened by means of the first operating element 9.1 in a first position and the second controllable valve is closed at the same time, a negative pressure can be applied to the tip of the cannula unit 5 by means of the suction instrument and fluid and tissue can be aspirated from the situs. If the first controllable valve is closed in a second position by means of the first operating element 9.1 and the second controllable valve is open at the same time, the rinsing medium can be conveyed to the tip of the cannula unit 5 by means of the rinsing device and the situs can be rinsed or moistened. Optionally, the operating element 9.1 can also be moved to a third position in which both controllable valves are closed.

[0121] The second operating element 9.2 is configured as a switch and is arranged on the handpiece 2. The second operating element 9.2 is used to switch between monopolar operation and bipolar operation. For this purpose, the second operating element 9.2 is communicatively connected to the stimulation device by means of the second interface 4. In a first position of the second operating element 9.2, the control device is caused to operate in bipolar mode and to stimulate tissue by means of both cannula tubes 5.2 and 5.1, the stimulus response of the stimulated tissue being detected by means of corresponding conductive electrodes on the patient (not shown). In a second position of the second operating element 9.2, the stimulation device is caused to operate in monopolar mode and to electrically stimulate tissue through, for example, the inner cannula tube 5.2, further requiring the attachment of a counter electrode to the patient (not shown). The stimulus response of the stimulated tissue can then be detected by means of at least one, preferably two, conductive electrodes on the patient (not shown). In a third position of the second operating element 9.2, no stimulation takes place and only a separate rinsing or suction process can be performed.

[0122] FIG. 6 schematically illustrates the system 100 for aspirating fluids and tissue and monitoring nerve tissue according to the second aspect of the present invention. The system 100 comprises one of the suction instruments 1 of FIGS. 1 to 5 according to the first aspect of the present invention, as well as the suction instrument 10, the rinsing device 20, an IOM system 30 and at least one, preferably two, additional conductive electrodes 50 (for clarity, only one conductive electrode is shown).

[0123] The IOM system 30 may be a control device comprising a data processing device (e.g., computer, laptop, etc.). The IOM system 30 includes a stimulation device 31 and a monitoring device 32 communicatively connected to the stimulation device 31. The stimulation device 31 and the monitoring device 32 may be integrated as separate hardware modules in the IOM system 30, or implemented as software modules in the IOM system 30.

[0124] The suction instrument 1 is fluidly connected to both the suction instrument 10 and the rinsing device 20 at the first interface 3 by means of a semirigid tube, exemplarily comprising two separate fluid lines. Further, at the second interface 4, the suction instrument 1 is electrically connected to the IOM system 30 or directly to the stimulation device 31 by means of a bipolar cable.

[0125] If bipolar operation is selected (for example, by means of the second operating element, not shown here), the stimulation device 31 can electrically stimulate tissue that is touched with the tip of the cannula unit 5 by means of both cannula tubes 5.1 and 5.2. The stimulation response of the stimulated tissue is detected by means of one, preferably two, additional conductive electrodes 50 attached to the patient (executed here as a needle electrode) and passed on to the monitoring device 32 as a conductive signal. The derivative signal may be amplified by an amplifier (analog or digital, not shown) and/or filtered by a filter device (not shown). The user, for example a surgeon, and alternatively or additionally the monitoring device 32 monitor the reject signal and compare it to predefined thresholds. The monitoring device 32 may output the detection signal and additionally a warning signal, if a limit value is exceeded, visually by means of a screen (not shown) and/or acoustically by means of a loudspeaker (not shown).

[0126] The conductive electrodes 50, here needle electrodes or alternatively surface electrodes, are electrically connected to the IOM system 30, or are directly connected to the monitoring device 32 by means of cables.

[0127] Provided that the stimulation device 31 is set to monopolar operation, tissue in the situs is stimulated, for example, by means of the inner cannula tube 5.2 and an additional counter electrode (not shown) attached to the patient and electrically connected to the stimulation device 31 or the IOM system 30, and the stimulus response of the stimulated tissue is detected by means of the conductive electrodes 50. The detected stimulus response is passed to the monitoring device 32 as a reject signal. The reject signal may be amplified by an amplifier (analog or digital, not shown) and additionally or alternatively filtered by a filter device (not shown). The user, for example a surgeon, and alternatively or additionally the monitoring unit 32 monitor the reject signal and compare it to predefined threshold values. The monitoring unit 32 may output the reject signal and a warning signal, if a limit value is exceeded, visually by means of a display screen (not shown) and/or acoustically by means of a loudspeaker (not shown).

[0128] Before performing, for example, a tumor resection in the brain, the suction instrument 1 is connected to the IOM system 30 or directly to the stimulation device 31 by means of the bipolar cable. The conduction takes place by means of additionally inserted conduction electrodes 50 in (needle electrode) or on (surface electrode) muscles. Preferably, different muscles of the upper extremities or the head are selected and provided with several conductive electrodes 50. During tumor resection in the brain, the tip of the cannula unit 5 is placed at the site to be resected and the tissue at the tip of the cannula unit 5 between the inner cannula tube 5.2 and the outer cannula tube 5.1 is electrically stimulated by adding current to the inner cannula tube 5.2. A check is made to see whether or not the stimulation triggers an MEP (motor evoked potential) at this location. If no MEP is elicited on the motor cortex, it is tumorous tissue that can be resected, whereas successful MEP derivation indicates that it is functionally relevant tissue and stimulation and resection should be continued at another site. Monopolar stimulation is performed by means of one of the two stimulation poles on the cannula unit 5, preferably the inner cannula tube 5.2, and an additional counter electrode inserted on the patient. The conductive electrodes 50 are placed according to the bipolar stimulation. In the present case, the monopolar stimulation can also serve as a distance radar. Depending on the stimulation intensity, it can be estimated at what distance the motor pathways are arranged. Here, a rule of thumb of 1 mA per 1 mm applies. This means that successful MEP stimulation at 5 mA indicates that the pyramidal tract is approximately 5 mm away. The tip of the cannula unit 5 can be at the tissue under examination at any time during critical phases of the procedure and stimulate it continuously (continuous subcortical mapping). Fluids and tumor tissue are aspirated through the lumen 5.4 of the inner cannula tube 5.2 without damaging the patient's nearby nerve tracts. Serious consequences such as deficits and paralysis are avoided for the most part.

[0129] The following example serves to illustrate the present invention without limiting its scope.

[0130] The subject is the removal of a vestibular schwannoma, which is also called acoustic neuroma (AKN). Vestibular schwannoma is a tumor that originates from the vestibulocochlear nerve sheath and is directly adjacent to this nerve. The vestibulocochlear nerve is a cranial nerve responsible for hearing and balance function. Classic complaints of patients with vestibular schwannoma are dizziness, hearing loss and tinnitus. Pronounced vestibular schwannomas can also affect the function of the facial nerve. Removal of an AKN is performed in neurosurgery with the use of intraoperative neuromonitoring. Essential here is the monitoring of auditory function by means of acoustic evoked potentials and of facial nerve function by means of electromyographic (EMG) measurement. Electrical stimulation is also used in this context. In the case of extensive tumors, monitoring of other cranial nerves (e.g., the trigeminal nerve and caudal cranial nerves) by EMG may be advisable.

[0131] In this case, suction instrument 1 or the bipolar mapping suction instrument is used for direct stimulation of the facial nerve or the other cranial nerves. Both bipolar and monopolar stimulation can be used here, which means that the conductive electrodes 50 are placed near the situs. The two connection pins of the second interface 4 of the suction instrument 1 are connected to the stimulation device 31 of the IOM system 30 by means of a bipolar cable with touch proof sockets. The handpiece 2 of the suction instrument 1 is fluidly connected to a suction instrument 10 with a semirigid tube at the first interface 3. In this case, the conductive electrodes 50 are placed in the target muscles of the cranial nerves. In the case of the facial nerve, for example, this is predominantly the mimic muscles of the face.

[0132] After access has been gained through skin incision and craniotomy behind the ear, the general function of the facial nerve can be estimated by means of monopolar stimulation, which is activated either by the second operating element 9.2 (switch) on the handpiece 2 or disconnection of one of the sockets of the bipolar cable, as well as an approximate determination of the distance to the nerve by stimulation threshold determination.

[0133] During stimulation, a monitor of the IOM System 30 displays the stimulus response in real time for interpretation and acoustically indicates it by means of a loudspeaker. At the same time, aspiration of fluids or tissue can be performed with the same instrument. In the further course of the operation, when this is performed in the direct vicinity of the cranial nerves, the system is switched to the bipolar function (by means of the second operating element 9.2 (switch) on the handpiece 2 or connection of the second socket of the bipolar cable to the second interface 4). Now the individual cranial nerves can be identified very selectively by bipolar stimulation. Continuous mapping allows the surgeon to know exactly where the cranial nerves and tumor are arranged, allowing for better targeted nerve sparing. Once a stimulus response is triggered, it is healthy and functional nerve tissue. If, on the other hand, no stimulus response is triggered, it is tumorous tissue that is to be resected. The fact that the suction instrument and the stimulation probe are combined in the suction instrument 1 or the bipolar mapping suction instrument allows close monitoring of the nerves and control of their function, as there is no need to change instruments. Additionally or alternatively, impedance spectroscopy can be used to differentiate tumor tissue from healthy tissue by measuring the impedance of the tissue surrounding the tip of the cannula tube 5.

[0134] To prevent the situs from drying out or surgical residues from drying on, the suction instrument 1 can also be used to flush the situs. The rinsing fluids and the tissue residues can then be aspirated with the suction instrument 1. The suction process or the suction strength can be controlled with the suction control opening 8 on the handpiece 2.

[0135] Light is emitted from the handpiece 2 or alternatively from the tip of the cannula unit 5 by means of an LED or a light guide. This provides additional illumination of the operating area. Optionally, the tracking element 7 can additionally be plugged onto the handpiece 2. Cameras of the navigation system 40 can then determine the current position and pose of the suction instrument 1 and track it. This offers significant advantages, particularly in neurosurgery and spinal surgery, such as increased precision and orientation during minimally invasive surgical procedures.

[0136] The main advantage of the suction instrument 1 or the bipolar mapping suction instrument is thus that it is no longer necessary to change instruments in a cumbersome manner. The suction instrument 1 combines a suction instrument with two stimulation contacts. The goal of complete tumor resection without damaging nearby nerve tracts is supported and simplified with the suction instrument 1. Furthermore, the surgical time is shortened by avoiding the need to change instruments. Bipolar stimulation also enables focused and selective stimulation and identification of nerve pathways, and the switching function between bipolar operation and monopolar operation enables the two methods to be merged into one instrument.

[0137] Although the present invention has been fully described above with reference to preferred embodiments, it is not limited thereto, but is modifiable in a variety of ways.

LIST OF REFERENCE NUMERALS

[0138] 1 Suction instrument [0139] 2 Handpiece [0140] 3 First interface [0141] 4 Second interface [0142] 4.1 Bipolar cable [0143] 4.2 Sockets [0144] 4.3 Electrical contact [0145] 5 Cannula unit [0146] 5.1 Outer cannula tube [0147] 5.2 Inner cannula tube [0148] 5.3 Insulation [0149] 6 LED [0150] 7 Tracking element [0151] 8 Suction control opening [0152] 9.1 First operating element [0153] 9.2 Second operating element [0154] 10 Suction instrument [0155] 20 Rinsing device [0156] 30 IOM system [0157] 31 Stimulation device [0158] 32 Monitoring device [0159] 40 Navigation device [0160] 50 Deflecting electrode