Medical Instrument for Minimally Invasive Removal of Biological Material from a Human or Animal Body

Abstract

Described is a medical instrument (1) for the minimally invasive removal of biological material from a human or animal body with a hollow needle (2), which, at a distal end (4) delimiting an interior (3) of the hollow needle (2), includes a peripheral edge (5) having a cutting edge, at least in sections, and with a cutting wire (6), which is arranged such that the cutting wire (6) can be moved relative to the hollow needle (2) at least partially outside the interior (3).

The technical solution described is characterized in that, in the interior (3) of the hollow needle (2), a guide element (7), slidable in the longitudinal direction of the hollow needle (2), is provided, at which the cutting wire (6) is fastened at least at one point and that a means of movement (8) for moving the cutting wire (6) is provided, through which a length of a part of the cutting wire (6) located outside the interior (3) can be changed in a targeted manner as a function of the actuation of a control element (11) acting on the means of movement (8).

Claims

1. A medical instrument (1) for the minimally invasive removal of biological material from a human or animal body with a hollow needle (2), which, at a distal end (4) delimiting an interior (3) of the hollow needle (2), includes a peripheral edge (5) having a cutting edge at least in sections, and with a cutting wire (6), which is arranged such that the cutting wire (6) can be moved relative to the hollow needle (2) at least partially outside the interior (3), characterized in that in the interior (3) of the hollow needle (2), a guide element (7), slidable in the longitudinal direction of the hollow needle (2), is provided, at which the cutting wire (6) is fastened at least at one point, and that a means of movement (8) for moving the cutting wire (6) is provided, through which a length of a part of the cutting wire (6) located outside the interior (3) can be changed in a targeted manner as a function of the actuation of a control element (11) acting on the means of movement (8).

2. The medical instrument (1) according to claim 1, characterized in that the means of movement (8) is designed such that the cutting wire (6) outside the interior (3) of the hollow needle (2) can be shaped into a cutting loop (10) at least partially enclosing a cutting area (9), wherein a size of the cutting area (9) can be changed in a targeted manner as a function of the actuation of the control element (11).

3. The medical instrument (1) according to claim 1, characterized in that the guide element (7) with the cutting wire (6) fastened thereon is arranged in a guide sleeve (12) in the interior (3) of the hollow needle (2).

4. The medical instrument (1) according to claim 3, characterized in that the guide element (7) has a recess (13), at least in sections, in which at least part of the cutting wire (6) is arranged.

5. The medical instrument (1) according to claim 1, characterized in that, on an outer side of a wall of the hollow needle (14) circumferentially enclosing the interior of the hollow needle (2), at least one dilator element (15) is arranged, which, at least in areas, can be moved relative to the wall of the hollow needle (14) from a rest position into an engagement position.

6. The medical instrument (1) according to claim 5, characterized in that a surface of the dilator element (15) in the rest position is arranged at least approximately parallel to a surface delimiting the outer side of the wall of the hollow needle (14).

7. The medical instrument (1) according to claim 5, characterized in that the dilator element (15) in its rest position is arranged sleeve-shaped and coaxially to the wall of the hollow needle (14) and has at least two dilator arms (16a, 16b) movable in different directions into the engagement position.

8. The medical instrument (1) according to claim 5, characterized in that the dilator element (15) comprises at least one shape-memory material.

9. The medical instrument (1) according to claim 1, characterized in that a gripping element (17), which can be moved out of the interior (3) beyond the distal end (4), is provided for fixation of the biological material.

10. The medical instrument (1) according to claim 9, characterized in that the gripping element (17) is arranged in a movable manner relative to the guide element (7).

11. The medical instrument (1) according to claim 9, characterized in that the gripping element (17) is arranged at least partially in the interior of the guide element (7).

12. The medical instrument (1) according to claim 9, characterized in that the gripping element is partially arranged in the interior of the hollow needle, between the wall of the hollow needle and the guide element.

13. The medical instrument (1) according to claim 9, characterized in that the gripping element (17) comprises at least one shape-memory material.

14. The medical instrument (1) according to claim 1, characterized in that an operating situation can be created, in which the cutting wire (6) is supplied with electrical energy and forms a pair of electrodes with the guide element (7), the gripping element (17), an electrically conductive element arranged in the interior of the hollow needle (2), a sleeve arranged in the interior (3) of the hollow needle (2) or the wall of the hollow needle (14).

15. The medical instrument (1) according to claim 1, exclusively manufactured from non-magnetic materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In the following, the invention is set forth in more detail without restriction of the general idea of the invention on the basis of embodiments with reference to the figures. These show:

[0035] FIG. 1: lateral view of a medical instrument designed according to the invention for the removal of biological material from a human or animal body;

[0036] FIG. 2: top view of the distal end of a hollow needle of a medical instrument designed according to the invention; as well as

[0037] FIG. 3: section of a schematic cross-sectional view of the hollow needle of a medical instrument designed according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] FIG. 1 shows a medical instrument 1 for the removal of biological material, in particular a tumor, such as a mammary carcinoma, from a human or animal body in a lateral view. The instrument 1 includes a handle 18, at which an operator, i.e., in particular a physician performing the procedure, can grab the instrument 1, move it in a suitable manner and initiate different operating functions by actuating at least one control element 11.

[0039] Thus, in the area of the handle 18, control elements provided for operating the instrument are arranged, via which the operator can actuate various elements and means of movement 8 of the medical instrument 1, and in particular move a cutting tool, which here is designed as a cutting wire 6 fastened to a likewise movable guide element 7, a gripping element 17 for fixation of the cut-out biological material as well as a dilator element 15.

[0040] According to the embodiment shown in FIG. 1, the medical instrument 1 includes a hollow needle 2, designed in the shape of a hollow cylinder or a sleeve, in the interior 3 of which a guide element 7, movably arranged in the longitudinal direction of the hollow needle 2, is provided. In the operating state represented in FIG. 1, the guide element 7 is located in a position, in which the guide element 7 protrudes beyond the distal end 4 of the interior 3 of the hollow needle 2. Furthermore, at the distal end 4 of the guide element 7, a cutting wire 6 is fastened, which can be moved due to manual actuation of a control element 11 and the means of movement 8 activated thereby. Apart from that, the cutting wire 6 is arranged in a recess 13, designed as a notch, which extends in the guide element 7 in its longitudinal direction, and can be moved relative to the guide element 7, so that outside the interior 3 of the hollow needle 2, a cutting loop 10, at least partially enclosing a cutting area 9, can be formed. For that, suitable holding and/or deflection means are provided at the guide element 7, which act on the cutting wire 6 such that, upon moving the cutting wire 6 along the guide element 7 in the direction towards the distal end 20 of the guide element 7, not only the length of the cutting wire 6 located outside the interior 3 is increased, but also a suitable cutting loop 10 is formed. This process is performed by the operator in a controlled manner by actuating at least one control element 11 in the area of the gripping element 17.

[0041] According to the embodiment shown in FIG. 1, thus, by moving the cutting wire 6, a cutting loop 10 outside the interior 3 of the hollow needle 2 can be created, which is used as a cutting element. The size of this cutting loop 10, and thus of the cutting area 9 at least partially enclosed by this loop 10, can be adapted by the operator as needed.

[0042] Preferably, the removal of biological material, in particular a tumor with a mean diameter of up to 2 cm from the female breast, is undertaken with the aid of an imaging technique, for example an ultrasonic imaging method, a mammography or magnetic resonance imaging (MRI), or imaging techniques that can be used in the future, such as tomosynthesis or rotational computed tomography, so that the operator can reach the tumor in a safe and targeted manner and cut it out of the healthy tissue with high accuracy.

[0043] Furthermore, the medical instrument 1 shown in FIG. 1 includes a dilator element 15 on the outer side of the wall of the hollow needle 14 in the form of a sleeve with four dilator arms 16, the distal ends of which can be respectively folded out. As soon as the hollow needle 2 with the cut-out biological material is to be removed from a human or animal body, the operator can actuate the dilator arms 16, again via a control or operating element, so that these respectively move outward with their distal ends and create a wedge shape, so that the cut-out biological material can be moved through a comparatively large passage opening through the surrounding healthy tissue through the body, and finally can be removed therefrom.

[0044] Furthermore, a gripping element 17 with four gripping arms is arranged at the distal end 4 of the hollow needle 2, which arms, once the biological material to be removed has been cut out, are placed around the cut-out material, so that it is ensured that the biological material can be removed from the body as completely as possible and in the original orientation it had inside the body. In addition, according to the embodiment shown in FIG. 1, an anchor element 21 is provided at the distal end 20 of the guide element 7, which in a rest position is stored inside the guide element 7, and then, when the hollow needle 2 as well as the guide element 7, as will be explained in more detail further below, are located in the engagement position in the body, is extended from the guide element 7. The anchor element 21 fixes the hollow needle 2 with the guide element 7 in the engagement position during the cutting process.

[0045] For the removal of biological material from a human or animal body, in particular a tumor, for example a mammary carcinoma, the hollow needle 2, with the guide element 7 located in the interior 3 of the hollow needle 2 while in the rest position and the cutting wire 6 fastened thereon on one side, is inserted into the breast with the aid of an imaging technique, such as an ultrasonic imaging diagnostic method. In the immediate vicinity of the tumor to be removed, the guide element 7, with the cutting wire 6 fastened thereon, is extended from the interior of the hollow needle 2. It is likewise conceivable to extend the guide element 7 and the cutting wire 6 upon approaching the tumor already, and to thus already create an enlarged passage opening or a gap, resp., by means of the cutting wire 6, in particular a shaped cutting loop 10, through which the hollow needle 2 with the cut-out biological material can be removed from the body later on.

[0046] Finally, the guide element 7 with the cutting wire 6 is pierced into the center of the tumor, pushed through it, and the movement is stopped as soon as the distal end 20 of the guide element 7, i.e., the tip of the medical instrument 1, is located about 3 mm behind the tumor. Now the cutting wire 6 is moved such that a cutting loop 10 with exactly the required size is formed, i.e., the required radius is set. In that, the mean diameter of the cut-out biological material is usually about 1 cm larger than that of a tumor to be removed. In this manner, the resection size can be exactly set by shifting the cutting wire 6 and respective formation of a cutting loop 10. With a rotational movement either by 360° or by 180°, respectively in opposite directions, the biological material is finally cut out in the shape of a sphere. It is even possible that the operator moves the cutting wire 6 in the longitudinal direction of the guide element 7, also during the cutting process, if needed, and thus changes the part of the cutting wire 6 located outside the interior 3 of the hollow needle 2, and thus the size of the cutting loop 10. In this case, the cut-out material has a shape deviating from the spherical shape.

[0047] Once the biological material intended for removal, here a tumor in the female breast, has been cut out, the cutting wire 6 is retracted into the interior 3 of the hollow needle 2 such that the size of the cutting area 9, and thus of the cutting loop 10, is about halved. This comparatively small cutting loop 10 remains in the tumor to be removed, in order to stabilize it in its longitudinal axis and to guarantee safe and easy removal. Before the tumor is moved through the body, first, a gripping element 17, likewise arranged in the interior 3 of the hollow needle 2, in particular its four-armed gripping claw, is extended and the cut-out tumor fixed by means of the gripping claws. Subsequently, the cut-out tumor is carefully moved out of the body. In order to facilitate this process, in particular to provide a passage opening for the tumor to be removed as large as possible, prior to retraction, the dilator element 15 in the shape of a four-armed, dilating sleeve is actuated, so that the individual dilator arms 16 are moved outward. In this manner, a wedge is created, which generates further facilitation upon removal of the tumor. In order to realize the gentlest possible tumor removal through the surrounding healthy tissue, it is conceivable that the passage opening is already enlarged upon approaching the tumor by means of a cutting loop 10. Preferably, a cutting loop 10 provided and used according to the invention can be supplied with electrical energy and forms a pair of electrodes together with a further electrode, such as the wall of the hollow needle 14 or another element in the interior 3 of the hollow needle 2, between which an electric arc supporting the cutting process is formed. Furthermore, it is conceivable to enlarge the opening for removal of the biological material by means of a knife incision.

[0048] FIG. 2 shows the distal end 4 of a hollow needle 2 of a medical instrument 1 designed according to the invention in a top view. It is clearly visible that the individual components, such as the cutting wire 6, the wall of the hollow needle 14, a guide sleeve 12 for receiving the guide element 7 as well as the guide element 7 with the cutting wire 6 and the anchor element 21 arranged in the interior, are arranged concentrically around a longitudinal center axis of the hollow needle 2.

[0049] According to the embodiment shown in FIG. 2, the wall of the hollow needle 14 circumferentially encloses an interior 3, in which a further sleeve, the so-called guide sleeve 12, extends in the longitudinal direction. Within this guide sleeve 12, the guide element 7 is movably arranged in the longitudinal direction. Furthermore, the guide element 7 includes a recess 13 in the shape of a notch extending in the longitudinal direction, in which the cutting wire 6 used as a cutting element is arranged.

[0050] Furthermore, the guide element 7 includes a cylindrical borehole 19, likewise extending in the longitudinal direction, in which an anchor element 21 is arranged.

[0051] On the outer side of the wall of the hollow cylinder 14, a dilator element 15 is located, which includes four dilator arms 16a, 16b, 16c, 16d arranged in parallel to the outer surface of the wall of the hollow cylinder and shaped in parallel hereto, which can be moved and, upon retraction of the hollow needle 2 from the patient's body, can be distanced from the wall of the hollow needle 14, at least in sections, i.e., can be dilated. In this manner, a wedge can be created as needed, which, upon movement of the hollow needle 2 in the proximal direction, pushes the surrounding, usually healthy tissue out of the way, and thus enlarges the passage opening for passing the hollow needle 2 with the cut-out tumor.

[0052] FIG. 3 further shows the hollow needle 2 of a medical instrument 1 designed according to the invention with the remaining components provided in this area in a schematic cross-sectional view. In the interior 3 of the hollow needle 2, the guide element 7 is located, which is arranged in a guide sleeve 12. The guide element 7 includes a recess 13 in the shape of a notch extending in the longitudinal direction for receiving the cutting wire 6, which forms the cutting element.

[0053] The cutting wire 6 as well as the guide sleeve 12, within which the guide element 7 is arranged, are connected with a power supply in an electrically conductive manner and, in a special operating situation, for a so-called bipolar application, form a pair of electrodes, of which the cutting wire 6 represents the active electrode. After applying a current of suitable strength, a current flow is initiated between these two electrodes and an electric arc is formed, through which the cutting process can at least be supported. Contrary to known monopolar applications of high-frequency surgery, the bipolar application above all has the advantages that the current flow is locally restricted in the patient's body and no neutral electrode is required.

[0054] Furthermore, a gripping element 17 with a plurality of gripping arms, extending in the longitudinal direction of the hollow needle 2, is provided, which arms circumferentially surround the guide sleeve 12 and in that are arranged between the guide sleeve 12 and the wall of the hollow needle 14. At the distal end of this gripping element 17 with the plurality of gripping arms, gripping claws are located, which serve fixation of the cut-out biological material.

[0055] On the outer side of the wall of the hollow needle 14 and coaxially hereto, there is a dilator element 15, which includes individual dilator arms 16, which, upon removal of the cut-out biological material from the body, move outward in sections and thus create a passage opening, through which the cut-out biological material can be removed in a comparatively easy manner and in one piece.

LIST OF REFERENCE NUMERALS

[0056] 1 Medical instrument [0057] 2 Hollow needle [0058] 3 Interior of the hollow needle [0059] 4 Distal end of the hollow needle [0060] Peripheral edge [0061] 6 Cutting wire [0062] 7 Guide element [0063] 8 Means of movement [0064] 9 Cutting area [0065] 10 Cutting loop [0066] 11 Control element [0067] 12 Guide sleeve [0068] 13 Recess [0069] 14 Wall of the hollow needle [0070] 15 Dilator element [0071] 16 Dilator arms [0072] 17 Gripping element [0073] 18 Handle [0074] 19 Borehole in the guide element [0075] 20 Distal end of the guide element [0076] 21 Anchor element