DE20211934U1 - Biopsy device for taking tissue samples under vacuum - Google Patents

Description

Biopsy device for taking tissue samples under vacuum.

The invention relates to a biopsy device, consisting of a handpiece with drive elements into which a biopsy needle is inserted, whereby a part of the part of the biopsy needle protruding beyond the handpiece can be inserted into the tissue to be examined with its sampling chamber and the tissue sample to be examined penetrates into the opening of the sampling chamber by means of negative pressure and is then separated by means of a longitudinally movable sample separation device and in a further step the sample is removed from the sampling chamber.

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A method and a device for cutting out tissue is already known from GMS 202 04363.0, in which the tissue is sucked into a sampling area of the biopsy needle under the influence of a vacuum. In this device, the tissue is sucked in via the blunt longitudinal edge of the sampling chamber by the negative pressure and the tissue penetrates into the sampling chamber to different depths depending on its strength. Since the edges of the sampling chamber are blunt, the tissue is bent over the edges and drawn into the sampling chamber as far as possible. The actual cutting out of the sample, which is sucked into the sampling chamber, takes place via a cutting device that surrounds the outside of the biopsy needle and is pushed longitudinally over the sampling chamber of the hollow needle in a rotating manner. The separated sample is initially stored in the needle and held by the cutting sleeve. After the needle has been removed from the tissue and the sample collection chamber has been opened, the sample is blown out using the vacuum generator to generate compressed air. In order to create a vacuum in the hollow needle, the handpiece, into which the hollow needle is slidably integrated, is connected to a vacuum generator arranged in the handpiece via a flexible line.

In the known biopsy device, the tissue sample to be taken penetrates into the sampling chamber of the biopsy needle with pressure support to varying depths depending on the tissue structure and is then cut off by means of the cutting edge on the sample separation device of the cutting sleeve, which is designed as a coaxial sleeve.

The needle is cut off lengthwise. This known method works reliably with normal tissue. However, with hard and/or tough tissue, sampling is not satisfactory because the insertion or drawing of the sample into the sampling chamber is insufficient. The filling volume in the sampling chamber does not meet the requirements; the reason for this could be that with tough and/or hard tissue, the tissue acts as a bridge over the drawing chamber through the longitudinal edges and only a small amount of tissue penetrates into the sampling chamber.

The invention is based on the task of designing the sampling in such a way that even with hard and/or tough tissue, the sampling meets the pathological requirements in terms of size and tissue architectural structure, i.e. the filling level of the sampling chamber should always be constant and independent of the structure of the tissue. Furthermore, the control of the drives should be designed in such a way that it meets the safety requirements.

The solution according to the invention consists in that the two longitudinal side edges of the sampling chamber 71 are designed as cutting edges and the cutting edges are moved slightly back and forth several times during and/or after opening the sampling chamber by moving the biopsy needle, wherein the lateral cutting effect is supported in particular by the applied negative pressure in the biopsy needle and thus enables a lateral separation of the tissue and only then is the sample completely separated out by actuating the separation device.

The brief back and forth movement of the biopsy needle causes the tissue to be pulled against the cutting edge under the influence of the negative pressure, and the back and forth movement of the sampling chamber results in the tissue being separated sideways, so that the tissue can be drawn into the sampling chamber more easily after separation. This reliably ensures that the sampling chamber is filled to a good level even with hard and/or tough tissue, i.e. the tissue sample corresponds to the required conditions in terms of size, weight and structure. The shaking movement can be

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of the drive and continue throughout the entire opening process. This facilitates the insertion of the sample into the sampling chamber under vacuum, since the lateral separation of the tissue runs from distal to proximal.

But even a brief shaking after opening the sampling chamber will achieve the desired effect. The shaking movement to separate the tissue sideways can also take place during and after opening.

If additional pressure is applied from the outside, particularly during the shaking movement or during the entire sampling process, the cutting effect of the cutting edge or the cutting edges is further increased during the shaking movement. This external pressure can be generated, for example, by pressing the ultrasound head or other compression devices.

Since biopsy needles are single-use items (disposable parts), the design of the cutting edges must be inexpensive and simple. This is achieved by, for example, milling out or otherwise removing part (T1) of the wall thickness of the sampling chamber. In this way, the inner radius is converted into the outer radius by a vertical edge, i.e. the cutting edge is formed by the outer wall and the inner edge.

The stroke and the number of forward and backward movements of the biopsy needle can be set using programmable settings in the microprocessor to achieve optimal results. In general, a stroke of 2 mm and a 5-fold shaking movement have proven to be effective.

The shaking movement itself is generated by using the drive motor for the cutting sleeve and the tensioning of the tensioning device to pull the biopsy needle carrier and above it the tensioning carriage over the threaded sleeve of the cutting device against a short spiral spring that is arranged between the base block and the tensioning carriage.

However, as soon as the gear wheel of the threaded spindle runs against the threaded spindle nut, the direction of rotation of the motor is reversed and the spiral spring pushes the clamping slide back. A pipe connected to the cutting sleeve, the collar of which rests on a bracket , ensures that the cutting sleeve cannot move freely to the right (open position), but that this pulling movement is initiated.

loo. Repeating the forward and backward movement of 2 mm 5 times has proven to be particularly beneficial.

Due to this simple construction, the drive motor can be used for opening and closing the cutting sleeve, as well as for tensioning the biopsy needle for the shaking movement, which not only means saving additional drive units, but also allows for a compact design.

The control of the drive motors by sensors that are arranged on the drive motors and supply the signals to a programmable microprocessor is particularly suitable because the temporal sequence and the length movement of the individual units of the vacuum/pressure generator or cutting sleeve can be controlled by

no counting process can be controlled precisely. This revolution counting process control is also particularly advantageous because both forward and backward movement of the individual elements is possible by reversing the drive motors. Only during the tensioning process of the biopsy needle, which is carried out by the drive motor for the cutting device, is the position measurement communicated to the microprocessor via photocells.

For safety reasons, the program steps "clamping" and "ejecting the sample" are provided with a delay circuit. This means that these program steps must be called consciously.
When closing the cutting sleeve, it is moved approximately 2 mm beyond the closing position towards the needle tip and then moved back to the closing position. This ensures that the tissue fibers are completely severed and are not trapped in the cavity between the biopsy needle tip and the cutting sleeve.

An example of an embodiment is described in more detail below using drawings. It shows:

Fig. 1 Biopsy device with opened housing cover (perspective)

Fig. 2 Handpiece with the parts of the biopsy device arranged therein

(without housing base and lid) and exchangeable biopsy unit; (perspective view)

Fig. 3 Longitudinal section A-A through the biopsy needle in Fig.1

Fig. 3a Longitudinal section A-A through the biopsy needle in Fig. 1 (as Fig. 3) proximal part (enlarged)

Fig. 3b Enlargement of section A in Fig. 3a

Fig. 3c Enlargement of section B in Fig. 3a

Fig. 4 Cross section B - B in Fig. 3 (left housing part)

Fig. 5 Cross section C - C in Fig. 3 (right housing part)

Fig. 6 right housing end cover (inside) with integrated microswitch

Fig. 7 Front of the control panel

Fig. 8a Base block in X-axis seen from the front (perspective)

Fig. 8b Base block in X-axis seen from behind (perspective)

Fig. 9a Housing-mounted units of the biopsy device without housing cover

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and soil in the unstressed state

Fig. 9b Locking device in the unclamped state (section A-A) no Fig. 10a As Fig. 9, but clamping slide in clamped position Fig. 10b As Fig. 9a, but in locked state Fig. 11a Biopsy needle tip side view

Fig. 11 b Longitudinal section through Fig. 11 a (sampling chamber opened)

Fig. 11c As Fig. 11b, but (sampling chamber half open)

Fig. 11d As Fig. 11b (sampling chamber closed by cutting sleeve)

Fig. 11e section AA in Fig. 11a

Fig. 11f Section B - B in Fig. 11a

Fig. 11g Magnification of the cutting edge at A

&iacgr; Fig. 12 Biopsy needle holder with pressed-in biopsy needle/cutting sleeve and plastic part (from below, rotated by approx. 90°, perspective)

Fig. 13 Vacuum/pressure device, installation and drive (seen from behind, perspective)

Fig. 14a Vacuum pressure device with piston placed on the syringe base (starting position for vacuum generation and end position for pressure generation, partially cut open)

Fig. 14b Vacuum pressure device with retracted piston; end position of the vacuum stroke (partially cut away)

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Fig. 14c Release of the ventilation hole; (syringe plunger retracted over ventilation hole; pressure equalization position, partially cut open)

Fig. 14d Section A-A through the threaded spindle in Fig. 14c

Fig. 15 Base block and biopsy needle/cutting sleeve, prepared for fitting with photocells and microswitch for actual value recording

' In the housing interior of a handpiece 1 all necessary components for carrying out a

The handpiece 1 is integrated into the device required for vacuum biopsy (Fig. 1), so that no cables or lines are required from the housing of the handpiece to other external supply devices. The handpiece 1 thus represents a complete vacuum biopsy device that can be moved freely in all directions. The distal part of the hollow biopsy needle 2 with the cutting sleeve 3 that coaxially surrounds it protrudes from the distal housing end cover 6 and is used to take the tissue sample. Usually, at the beginning of the biopsy, a coaxial cannula is placed in the tissue, into which this part of the biopsy needle 2 with the cutting sleeve 3 is inserted. A connecting element 4 is guided outside the right proximal housing end cover 7, e.g. a transparent, flexible tube that connects the

*220 arranged vacuum/pressure generating device 5 with the inner cavity of the biopsy needle 2. The hollow connecting element 4 is arranged in the immediate vicinity of the housing end cover 7. The biopsy needle with cutting sleeve and further elements arranged in a biopsy needle carrier 37 forms, together with the connecting element 4 and the vacuum/pressure generating device 5, an element 20 which can be easily removed upwards and inserted and which is changed as required (Fig. 2). For this purpose, the housing cover 10 is opened. As Fig. 2 in particular shows, the biopsy device can be divided into parts which are firmly connected to the housing (disinfected parts) and a removable element 20 (sterile part). While the parts firmly connected to the housing are only disinfected, the removable element 20 is delivered in sterile packaging and is replaced as required, especially for each new patient.

In the embodiment described below, the vacuum/pressure generating device is arranged parallel to the biopsy needle. Within the scope of the invention, however, the vacuum/pressure generating device can also be arranged lying in the axis of the biopsy needle or the handpiece; it also does not require a separate connecting element if it is, for example, placed directly on the end of the biopsy needle.

Between the left and right housing end covers 6, 7 there is a housing base 9 and a housing cover 10 pivotably mounted in the housing end covers with a locking latch 11. The housing base 9 is clamped between the housing end covers 6, 7 or connected to the base block 8 via tie rods or screws, some of which are screwed into a base block δ. The housing cover 10 is pivotally connected via an axis fastened in the housing end covers 6, 7. The housing cover 10 is closed before the biopsy device is operated; the inner contour of the housing cover corresponds to the outer contour of the biopsy needle carrier 37, which will be described in more detail later. The base block 8 is arranged approximately in the center of the housing interior and is firmly connected to the housing base, e.g. via fixing elements and/or via a screw connection. The base block 8, which extends not only in the longitudinal axis from the center to the left, but also over the entire transverse surface, provides the drive elements for the vacuum/pressure generating device 5, the cutting sleeve 3

\ and the clamping device for the clamping slide 28, on which the biopsy needle carrier 37 is placed. Furthermore, the base block 8 has a holder 36, which is open at the top, for the biopsy needle/cutting sleeve and a further insert element 62 for the vacuum/pressure generating device.

To describe the position of the individual elements, as well as the position of the individual parts, in particular in the housing interior, a coordinate cross has been drawn in Fig. 1, with the coordinate center of the coordinate system being in the center of the base block 8 (Fig. 1). Accordingly, for the following description and for the claims, the direction information is considered to be left (distal) in the direction of the X-axis and right (proximal) in the opposite direction to the X-axis. For the other coordinates, the direction of the Y-axis is considered to be above, the opposite direction to the Y-axis is considered to be below, and the direction of the Z-axis is considered to be behind and the opposite direction to the Z-axis is considered to be

front (Fig. 1). The coordinate system divides the interior of the housing and the other references into left and right, front and back, and top and bottom.
With reference to these specifications, the common drive devices 106 for the clamping device and the cutting sleeve are located in the lower, front, left-hand housing part of the housing interior, and the drive device 105 (Fig. 13) for the vacuum/pressure generating device 5 is located in the lower, rear, left-hand housing part. The energy supply for the drive motors and the other electrical equipment, such as for the control and/or monitoring elements, is housed in the lower, right-hand part; batteries or a rechargeable battery 111, e.g. a 7.2V lithium-ion battery, 1Ah, are preferably used for this. The front, right-hand upper housing interior above the battery compartment is used largely for the clamping slide 28 with locking part (Fig. 5); this is connected to a block 26, which is part of the base block 8. The battery compartment is sealed at the top by a partition plate 114.
In the uppermost, front part of the housing interior there is a biopsy needle carrier 37 which can be inserted and removed into the U-shaped, upwardly open insertion holder 36 of the base block 8 and into the upwardly pointing tab 40 arranged on both sides of the clamping slide 28, in which the

Biopsy needle/cutting sleeve unit with drive parts is rotatably mounted, which extends over almost the entire length of the handpiece. The biopsy needle carrier is, as described later, longitudinally displaceable by means of the clamping slide. This

* means that when not tensioned, the left front surface of the biopsy needle carrier 37 almost touches the left housing end cover 6; when tensioned, the right front surface touches the right housing end cover 7. "Almost the entire length" means that the biopsy needle carrier is at least shorter by the amount that the housing interior is required for the tensioning process. If the tensioning path of the tensioning slide is, for example, 20 mm, the biopsy needle carrier must be able to be moved by at least this amount. In general, the tensioning path is between 15 and 25 mm, depending on the biopsy needle used. It is therefore advisable to design the interior for the greatest possible tensioning path plus a few mm.

The clamping device (right, front) itself consists of a clamping slide 28 guided on a bolt 30 , whereby the bolt can be screwed into the block 26 of the base block 8. The bolt 30 is held on the proximal side by a

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Spiral spring 31. On the distal side of the clamping slide, another short spiral spring 124 is arranged on the bolt 30. This short spiral spring is supported on the one hand on the block 26 and on the other hand on an inner lip 122 on the distal side of the clamping slide. The spiral spring 31 is supported on the opposite side (proximal side) of the lip of the clamping slide. The locking device (see in particular Fig. 9b and 10b) of the clamping slide is attached to the block 26. In the upper, rear, right-hand interior of the housing, the vacuum

/Pressure generating device 5 is housed with parts of the drive; the drive motor with reduction gear for the vacuum/pressure generating device is located in the left, lower, rear area of the housing interior.
The housing cover, the housing base, the housing end covers and the base block are preferably made of aluminum.

The handpiece 1 consists, as already described, of a housing which is formed from a housing base 9 with walls of different heights on the sides, a housing cover 10 adapted to the housing base with a longitudinally movable locking latch 11 and the two housing end covers 6 and 7. The housing base is connected to the two housing end covers via tie rods or screws, e.g. made of iron, which are partially screwed directly into the base block 8. The housing is approx. 200 mm long, the housing end covers have an approximately square cross-section, approx. 40 x 40 mm, (Fig. 2). The housing cover 10 can be pivoted about an axis 104 which is fastened in the housing end covers 6, 7.

f ; the holes 14 in the housing end covers are used for this purpose. The nose 12 of the locking latch 11 can be pushed into the recess 45 of the base block 8 to close the housing cover. The left housing end cover 6 has an upwardly open U-shaped passage 13 in the upper, front part for the part of the biopsy needle/cutting sleeve 2, 3 that projects forwards and the guide roller 81 arranged thereon. The rear housing end cover 7 has two upwardly open U-shaped passages 15, 16. The passage 15 corresponds to the passage 13; it receives the end of the round cross-section plastic part 47 placed on the hollow biopsy needle. A nozzle 63 of the vacuum/pressure generating device is inserted into the passage 16 (Fig. 2). A further plastic part 112 inserted into the plastic part 47 has a pin 17 which is used to connect the connecting element 4 with the outlet nozzle 64 of the vacuum

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/pressure generating device. The inner cavity of the biopsy needle is connected to the cavity of the piston/cylinder arrangement and the cavity of the vacuum/pressure generating device via the connecting element 4, which is also hollow. The connections are designed in such a way that neither air can penetrate into the system from the outside, nor can air escape to the outside in the event of excess pressure; the connection points are therefore airtight. As shown in particular in Fig. 6, a microswitch 18 is integrated into the feedthrough 16 of the housing end cover 7 on the lower side, the switching pin 19 of which projects into the feedthrough.
As soon as the nozzle 63 of the vacuum/pressure generating device is inserted into the bushing and the housing cover is closed, the switching pin 19 of the microswitch 18 is pressed downwards and the microswitch 18 releases the power supply. The connections for connecting a charging device can be installed in the bushings 97, 98 of the housing end cover.

On the front side of the housing base 9, a surface 113 is provided for the control panel (Fig. 7) with the control and monitoring elements attached to the housing. The control panel 57 to be attached to the housing is designed as a separate component, which is glued, for example, to the surface 113 of the housing base 9. This control panel 57 is connected via cables to other electronic components arranged in the housing, as well as to the power supply. Of the electrical/electronic components connected to the control panel,

^ the circuit board arranged in the space 39, which is located beneath the cover 46, should be mentioned. A programmable microprocessor and other electronic components are arranged on the circuit board. The semi-automatic sequence control, which will be described in detail later, is controlled by means of the microprocessor. The control panel mainly contains switches for operation and diodes for control. The actuating button 88 for the mechanical release of the tensioned tensioning slide protrudes from a recess 65 in the lower part of the housing and the control panel;

When designing the operating and monitoring elements, care was taken to ensure that there is a clear line between the clamping process of the clamping slide and the release of the clamping slide on the one hand, and the performance of the biopsy, such as the removal of the sample, and in particular the sampling by ejection of the

sample. Accordingly, the actuation button 88 (trigger) for the clamping slide has been placed to the right and the clamping button 90 which triggers the clamping of the clamping slide has been placed to the left. The program button 89 intended for carrying out the biopsy is in the middle. The control lamps for reset, carrying out the biopsy and ejecting the sample after opening the sample removal chamber are also in the middle. By pressing the program button 89, after inserting the removable element 20 and after closing and locking the housing cover and automatically setting the home position, two functions are called up, namely sample removal and sample ejection. After inserting the removable element and closing the cover, the reset diode 91 lights up yellow briefly and flashes while the home position is being set; after the starting position is set, the reset diode goes out. The sampling diode 92 (green) and the clamping diode (yellow) light up and indicate that the operator can call up either one or the other function. If he presses the clamping button 90, the clamping carriage 28 is brought into the clamping position and locked there. To prevent the clamping button from being pressed accidentally, it is equipped with a delay circuit of approx. 1.2 seconds. During the clamping process, the yellow clamping diode flashes; after the clamping process has been completed, the locking diode (green) lights up; the device, the needle, is ready to be shot into the tissue to be examined by triggering the actuation button 88. After the shot, the locking diode goes out and the clamping diode ►385 (yellow) and the sampling diode (green) light up. Both functions (clamping or sampling) can now be called up. When the program button 89 is pressed, the biopsy process is carried out automatically, as explained later. However, the clamping process could also be called up again. When the biopsy process (sample collection) is called up, it runs automatically. After the process is complete, the green flashing sample collection diode goes out and the yellow ejection diode lights up. Pressing the program button again starts the automated sample collection process. After the process is complete, the flashing ejection diode goes out and the yellow reset diode lights up, which means that the removable element 20 can be removed, or that by pressing the program button the device is automatically prepared for the collection of another sample. The process then follows again as already described, clamping

etc. or sampling. When pressing the program key 89 for sampling (for ejecting the sample), a delay circuit is provided to prevent ejection from taking place if the program key is accidentally touched without the needle being pulled out first.

The battery charging diode 96 shows the charge level of the battery or accumulators. As already described, the diodes are connected in such a way that when the called process is carried out, the diode flashes and when the process is completed, the diode for the next process lights up. If two options are available, both next diodes light up. The operator is then free to choose which selection he makes. The colors of the diodes are chosen so that processes in the tissue are shown in green, while processes outside are shown in yellow. Delay circuits (e.g. 1.2 - 1.5 seconds) are provided for the clamping and sampling functions to ensure that the process was deliberately called up. The mode of operation and control options are discussed in more detail in the description of the process. Symbols (pictograms) on the board symbolize the individual processes.
A perspective view of the base block 8 (seen from the front in the direction of the X-axis) is shown in Fig. 8a; the base block 8 from the back in the X-axis is shown in Fig. 8b (both views in perspective). The base block 8 can be divided into two halves in the longitudinal direction; the front part is used to attach the common drive for the cutting sleeve and clamping slide and in its upper part to support the

Biopsy needle carrier (Fig. 8a); the rear part is used to attach the drive for the vacuum/pressure generating device and to support one side of the vacuum/pressure generating device (Fig. 8b). Between the two drive motors 21, 58, under the central rib 87, a central electronic board is arranged in the space 39 below. The base block 8 has a U-shaped space 24 in its left, front part, into which a toothed roller 23, which is driven by the gear motor 21, is installed. For this purpose, the output shaft of the gear motor is mounted or inserted in an opening in the wall 25 of the base block 8. The toothed roller 23 is plugged onto the output shaft and fastened to it in a rotationally and displacement-proof manner, e.g. by means of a screw. On the other side, the toothed roller 23 is mounted in the wall 22 of the base block 8. A DC motor with a speed of approx. 11000 rpm is used as the drive motor.

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A planetary gear with a high reduction ratio is connected downstream of the DC motor, and the toothed roller 23 is mounted on its output shaft.

Another block 26 is formed on the wall 22 pointing to the right, which accommodates the pivotable double lever 33 for locking and also serves to fasten the bolt 30 for guiding the clamping slide 28. The bolt 30 is screwed into the threaded hole 29. During the clamping process, the clamping slide 28 slides to the right on the separating plate 114 arranged underneath. During the clamping process, the spiral spring 31 arranged on the threaded bolt 30 is compressed. The spiral spring rests with one end on an end piece 32 of the threaded bolt or directly on the housing end cover 7; the other end of the spiral spring, which projects into a blind hole in the clamping slide, rests via a washer on a lip 122 of the guide hole 115. The threaded bolt 30, which is fastened on the one hand in the housing end cover 7 and on the other hand in the block 26, has a short spiral spring 124 on its distal end, which is also supported on its proximal side on the lip in a coaxial blind bore 129 opposite the bore 115 via a further washer 125 on the circumferential lip 122. Both spiral springs have the same diameter and the distal and proximal bores 129,115 in the clamping slide and the distal-side bore 128 in the block 26 are designed in such a way that the spiral springs can be easily inserted. All bores are arranged coaxially to the bolt 30.

At the same height as the circumferential lip in the blind bore of the slide, the

Threaded bolt 30 has a collar 123. The clamping slide 28 is held in its initial position (rest position) by the slightly pre-tensioned springs 31, 124 via the washers in the rest position, as shown in Fig. 3a and 3c. The washers lie on the corresponding side of the collar and the lip and are vertical; if the slide is deflected to the right or left, the respective spring will try to return the clamping slide to its initial position, the clamping slide is held "floating" to a certain extent.
The clamping slide 28 slides mainly on the separating plate 114 and is secured against rotation by this and the side wall. An arm 99 of the double-armed lever 33 of the locking device engages in a groove 27 of the clamping slide 28 (Fig. 9a and 10a). The locking device integrated in the block 26 of the base block 8 consists of the

double-armed lever 33, which can be pivoted about a vertical axis 35 (seen in the Y-axis) by means of a compression spring 34. The axis 35, a vertical pin, is fastened in the holes 38 of the base block. In the unclamped state, the part 99 of the double-armed lever lies in the groove 27 of the clamping slide; the compressed spring 34 acts on the part 100 of the lever to press the locking button 88 outwards (forwards). As soon as the part 99 of the double-armed lever can engage in the recess 82 of the clamping slide, the actuating button 88 is pressed outwards. The clamping slide is locked in the clamped state by engaging the lever part 99 and can now be released with the actuating button 88 if required. Since the clamping slide is expediently made of

f plastic, it has proven useful to insert a

Metal part 83 should be used to avoid damaging the plastic, since the double-armed lever is made of metal. In contrast to the removable element 20, the handpiece with the replaced insert element can be used multiple times. The clamping path corresponds to the depth of penetration of the biopsy needle into the tissue. This means that the length of the lever 99 also corresponds to the clamping path. Since the penetration depths are generally between 15 and 25 mm, the same handpiece can be used for different penetration depths by designing the length of the lever 99 accordingly and changing the settings in the control accordingly.

&PSgr; The clamping slide 28 adjoining the block 26 is arranged at the same height as the block 26 and has approximately the same cross-section as the block 26. The clamping slide has two tabs 40 on its upper side. The upward-facing surface 41 of the clamping slide, as well as the upward-facing surface 44 of the block 26, as well as the upward-facing surface of the extension 42 of the base block 8, together form a flat bearing surface for the lower sliding surface 43 of the biopsy needle carrier 37 to be attached (see Fig. 2). The biopsy needle carrier is made of plastic.

When the clamping slide is moved from the unclamped initial state (Fig.

9a) into the tensioned state (Fig. 10a), i.e. to the right, the biopsy needle carrier 37 held by the tabs 40 slides over the surface 42 and 44. It is also conceivable that the sliding surfaces are not flat, as in the embodiment, but have specially designed sliding surfaces; it is important that the

Biopsy needle carrier 37 can slide smoothly and in a straight line on the sliding surface and that after the actuation button 88 is triggered, the biopsy needle can penetrate the tissue, the tumor, in a straight line. Therefore, the upper outer contour of the biopsy needle carrier is designed to match the inner contour of the housing cover and has only a small amount of play with the housing cover in order to prevent the biopsy needle from moving upwards, which is also an advantage during the clamping process.

Above the U-shaped space 24 for the toothed roller 23, at the height of the sliding surface 42, the base block 8 has a U-shaped holder 36 that is open at the top, among other things for inserting the biopsy needle/cutting sleeve. This holder serves primarily as

&iacgr; radial thrust bearing, i.e. for supporting the cutting sleeve connected

Drive part, the gear 74, or the plastic disk 78 to bring the clamping slide into its clamping position by means of the drive device 106, as will be described later.

In the rear, upper part of the base block, a further U-shaped insert element 62 is provided, into which the free end 61 of the threaded spindle of the vacuum pressure generating device protruding from the syringe body is inserted. In the middle, at the top, of the base block, a fastening for a plate is provided, which accommodates the recess 45, into which the nose 12 of the locking latch 11 of the housing cover is inserted. A cover arranged on the base block 8

' 46, which points to the left, separates the space for the drive motors and the inserted circuit board from the upper, left part of the housing interior, which is used primarily for storing the exchangeable biopsy needle carrier 37, including the biopsy needle and cutting sleeve. The cover 46 protects the electric gear motors and the circuit board from contamination. The circuit board for the electronics is located between the drive motors and below the central rib in space 39.

Fig. 2 shows the biopsy needle carrier 37, which can be inserted into the tabs 40 of the clamping slide 28 with biopsy needle 2 and cutting sleeve 3 as well as other parts.

The hollow, circular biopsy needle 2 has a needle tip 70, which is connected to the sampling chamber 71 (Fig. 11a - 11f). The biopsy needle 2, which has a round cross-section, is surrounded by a coaxially arranged, round cross-section cutting sleeve 3, which has a cutting edge 72 at its left end facing the sampling chamber.

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which serves to cut out the tissue sample after inserting the biopsy needle (with closed sampling chamber) and after opening the sampling chamber and sucking the sample into the sampling chamber. The distally arranged cutting edge of the cutting sleeve is preferably perpendicular to the longitudinal axis of the biopsy needle and cutting sleeve. The cutting process takes place by rotation and simultaneous longitudinal displacement of the cutting sleeve by means of the threaded spindle drive. It is also conceivable that the movement is not continuous, but step-by-step or vibrating, i.e. the feed is moved back and forth at short intervals. As shown in particular in Fig. 11f in cross section, the longitudinal edges 68 of the sampling chamber lie above the center of the cross section, i.e. the sampling chamber is raised above the center by approx. 15 - 30 °. In order to improve the penetration of solid, hard tissue into the sampling chamber, the longitudinal edges have a cutting edge. This cutting edge on the edges is created by reducing the wall thickness from above by the piece of material T1 (Fig. 11). This connects the inner wall with radius ri to the outer wall with radius ra via a vertical surface or edge. The cutting edge therefore forms the outer wall with the vertical edge.

A threaded spindle sleeve 73 with a gear 74 arranged on the front side of the threaded spindle sleeve is attached to the other, proximal end of the cutting sleeve, facing away from the cutting edge 72. The threaded spindle sleeve with gear is arranged on the cutting sleeve so that it cannot rotate or slide. A threaded spindle nut 75, which is pressed firmly into the biopsy needle carrier 37, works together with the threaded spindle. The gear 74 is located on the left, i.e. in front of the start of the spindle sleeve. When the threaded spindle sleeve is rotated using the gear 74, the cutting sleeve is rotated and moved longitudinally over the biopsy needle 2.
Distal to the gear wheel 74, a pipe section 126 with the collar 127 is firmly connected to the threaded spindle. The pipe section is inserted into the holder 36, with the collar 127 lying distally in front of the holder. The length of the pipe section 126 corresponds approximately to the clamping path, whereby the wall thickness of the holder 36 must also be taken into account (see Fig. 3a and 3b). In the basic position of the device (closed sampling chamber), the collar 127 moves to the left, to the distal side, while after opening the sampling chamber on the holder 36 (distal side)

comes into contact. When the spindle sleeve with cutting device is rotated further, i.e. when attempting to open the sample extraction chamber further, the clamping slide is pulled towards block 26 against the effect of the short spiral spring. This allows the biopsy needle to be moved forwards and backwards, as described later.

The gear 74 at the left end of the threaded spindle meshes with the toothed roller 23 after the biopsy needle carrier has been inserted into the tabs 40. In order to be able to insert the biopsy needle carrier 37 into the tabs of the clamping slide when the clamping slide is not clamped (Fig. 2), the biopsy needle carrier has two flat, parallel recesses 77. When the sliding surface of the biopsy needle carrier 37 is placed on the surfaces 41, 42 and 44, the cutting sleeve is simultaneously inserted into the holder 36 of the base block 8. A plastic disk 78 provided with a slight cone can be inserted on the left side of the gear to improve the rotatability of the spindle drive, particularly when the holder 36 serves as a support for clamping the clamping slide. If the biopsy needle carrier is correctly inserted, the biopsy needle carrier slides with the sliding surface 43 over the surfaces 42 and 41 to the right when the clamping slide is tightened. Since the sample removal chamber is closed first after the biopsy needle carrier is inserted, the gear 74 rests on the holder 36. If the toothed roller 23 is now driven further in the same direction, the k58o threaded spindle drive screws the clamping slide to the right via the biopsy needle carrier until it is locked; the biopsy needle is pulled inwards while the cutting sleeve remains in its position. After locking, the cutting sleeve protrudes beyond the biopsy needle tip. Therefore, after the clamping slide is locked, the cutting sleeve is rotated back to its starting position (opposite direction of rotation); the gear 74 moves from left to right in the toothed roller. After the clamping slide has been released, the biopsy needle holder and the biopsy needle holder/cutting sleeve with gear slide back to the left. The cutting sleeve can now be moved back to the right to open the sample extraction chamber until the collar 127 comes into contact.

The function of the "floating" clamping slide in conjunction with the controllable drive motor and the pipe section 126 connected to the cutting sleeve

with the Bund 127 is described in more detail in connection with the procedure of the biopsy.

The right end of the cutting sleeve is connected to the hollow biopsy needle via a sealing element 76 in a rotationally movable but air-tight manner so that neither air can penetrate between the biopsy needle and the cutting sleeve coaxially surrounding it, nor can air escape in the event of excess pressure. A round, also hollow plastic part 47 is placed air-tight on the right end of the biopsy needle 2 and is frictionally connected to the biopsy needle. The plastic part 47 has a bearing element 49 on its left end which is pressed into the biopsy needle carrier; at its right end protruding from the handpiece, another plastic part 112 is inserted which can rotate relative to the plastic part 47 and relative to the biopsy needle 2. An O-ring is inserted between the biopsy needle and the plastic part 112 for sealing. The plastic part has a pin 17 on its right end onto which the connecting element 4 is pushed in an air-tight manner. Also on the right-hand part protruding from the biopsy needle holder and the housing is a knurled disk 80, which can be used to radially adjust the position of the sampling chamber by turning it, without changing the position of the cutting sleeve. Turning the biopsy needle only causes the sampling chamber to turn. The plastic part 47 with the biopsy needle and cutting sleeve is pressed into the biopsy needle holder with the bearing element 49 and the threaded spindle nut 75. The biopsy needle is rotatably mounted in the biopsy needle holder and in the cutting sleeve via the bearing element 49 and its tight guide in the cutting sleeve, and can be moved along the longitudinal axis with the biopsy needle holder. As previously described, the cutting sleeve can be moved axially relative to the biopsy needle by turning it.

To the right of the bearing element 49, a polygon 50 is arranged on the plastic part, which can be locked to the biopsy needle carrier by clamping, so that the sampling area of the biopsy needle can be brought into the most favorable position for biopsy sampling and held by means of the knurled disk 80.

As shown in particular in Fig. 12, the cutting sleeve coaxially surrounding the biopsy needle is connected to the biopsy needle carrier 37 via the threaded spindle nut 75. The threaded spindle sleeve 73 is rotatably mounted in the threaded spindle nut 75. Rotation of the gear 74 by the drive motor of the toothed roller 23

causes the biopsy needle carrier and the tensioning carriage to be moved to the right as soon as the gear 74 comes into contact with the holder 36. If the gear is positioned within the length of the toothed roller 74, i.e. if the gear is free and is not in contact with the holder or the threaded spindle nut 75, the cutting sleeve can be adjusted on its own, e.g. after tensioning the needle to balance the needle tip and cutting sleeve in order to be guided into the starting position, or to open and close the sampling chamber. The pipe section with a collar attached to the distal side of the gear, which interacts with the holder 36, serves to set the needle in a brief shaking movement (forward and backward movement) in conjunction with the control system. When the toothed roller is driven via the gear 74, the sampling chamber is opened until the collar comes into contact with the holder 36 on the distal side. If this direction of rotation is maintained and the gear is not in contact with the threaded spindle nut, further rotation causes the clamping carriage to be pulled over the biopsy needle carrier to block 26 against the effect of the short spiral spring, as further opening of the cutting sleeve is not possible due to the collar being in contact. The clamping path is approximately 2mm. When the gear 74 stops on the threaded spindle nut, the direction of rotation of the motor is reversed and, with the help of the short spiral spring, the clamping carriage is pushed back to its starting position (rest position). As a sensor counts the number of motor revolutions and the actual values are stored in a programmable microprocessor, the motor speed can be reversed according to the specifications using appropriate specifications, so that the clamping carriage is pulled against the block again or moved back after release. The constant rotation of the direction of rotation of the motor, according to the specification, in conjunction with the clamping and releasing of the carriage, causes the biopsy needle to execute a shaking movement. Five forward and backward movements are generally sufficient to ensure a good sample even with hard and/or tough tissue. The forward and backward movement of the biopsy needle in conjunction with the sharpened cutting edge cuts through the tissue that is to be drawn into the sampling chamber by the vacuum at the side edges, which makes complete suction possible. The construction described enables the biopsy needle to be shaken with the cutting edges of the sampling chamber connected to it after opening the

sampling chamber. The same effect is achieved if this shaking movement is generated during opening, i.e. when the cutting sleeve is retracted, in order to reliably separate the tissue at the side edges. This shaking movement can be generated using electrical elements that are connected to the needle or the clamping slide. For example, the toothed roller on the proximal side can have a link that works together with a pin that pushes the clamping slide so that when the gear wheel turns, it performs a shaking movement that is transferred to the needle via a connection.

Details of the sampling chamber and the biopsy needle tip are shown in Fig.

^ 11a -11g. The sampling chamber 71 adjoining the needle tip 70 is open at the top over approximately 25% of its cross-section. Thus, with a biopsy needle outer diameter of 3.3 mm, the height H of the biopsy needle chamber is approximately

2.3 mm. The sampling chamber is approximately 15 to 25 mm long. The cavity of the biopsy needle is connected to this. At the transition, i.e. at the proximal end of the sampling chamber, the cavity cross-section of the biopsy needle is closed between 50% and 75% by a constriction, e.g. a plug 79 (Fig. 11b - 11e). The height of the plug is designed so that it reaches down over the recess for the sampling chamber, i.e. as Fig. 11e shows, there is an opening at the bottom of the sampling chamber with a height of 0.6 mm and an inner needle diameter of 3.0 mm. The vacuum is thereby primarily intended to

} Draw the tissue sample into the sampling chamber by continuously opening the sampling chamber and bring it into contact with the wall of the sampling chamber. If there is excess pressure in the biopsy needle cavity, the constriction, the plug, increases the pressure. The plug is approximately 10 mm long and is glued or welded into the cavity. Laser welding has shown that it is advantageous to make the left side of the plug thin by removing material from the front surface to a short length, approximately 2 mm. This welds the tube of the biopsy needle through to the front side of the plug in this area on the front surface and makes the front side airtight. The plug can also be shorter, provided the same effect is achieved. The plug can also be replaced by a lip or nose of approximately the same height. It is important that the constriction is designed in such a way that the vacuum in the sampling chamber is mainly effective from the bottom, so that the sample is

. 22

adheres to the wall of the sampling chamber and does not change its position. It has also proven advantageous to provide additional fixing means on the sampling wall. By sucking the sample into the sampling chamber from below, the sampling chamber is filled to a high degree and, above all, its design ensures that the sample is well fixed to the wall. Since the cutting sleeve cuts off the sample on the outside of the biopsy needle, this suction of the sample on the inside is maintained even during the cutting process. In addition, no tissue is sucked into the hollow cutting sleeve by the vacuum created by the cutting sleeve on the outside, and thus the tissue cannot be twisted or distorted by the rotating longitudinal movement of the cutting sleeve as it is held in place in the cutting sleeve interior. The quality of the sample is improved because the pathologist receives a starting material that corresponds to the cross-section of the cut and is not twisted or deformed. When the sample is ejected under pressure, the stopper 79 also completely cleans the sampling chamber so that no mixing occurs if the same thing happens again. Since the vacuum generating device is also used as a pressure generating device, the entire cavity, in particular the needle, is cleaned. For normal tissue, it is sufficient to use the wall thickness of the biopsy needle tube of approx. 0.15 mm as the side cutting edge. For hard and/or solid tissue, the degree of filling in the sampling chamber is not sufficient just by suction using a vacuum. By forming the long sides of the sampling chamber 71 into cutting edges 68, as shown in particular in Fig. 11g and Fig. 11f, the tissue of the sample is separated lengthwise by superimposing a brief shaking movement (as described) and by the effect of pressure, e.g. from the vacuum, so that the vacuum can draw the sample to the bottom of the sampling chamber much more effectively. The cutting effect can be increased by applying external pressure, e.g. using the ultrasound head or another compression device. By separating the lateral cut surfaces of the tissue sample to be taken, an excellent degree of filling is achieved even with hard and/or tough tissue, thus ensuring that sufficient material is available for the examination. The cutting edge on the long side of the sampling device is formed by cutting the section (T1) from the

¹ 23

The outer contour (ra) of the biopsy needle tube is retained, while the inner contour (ri) is converted into the outer contour by, for example, milling out the section T1 over a vertical wall (see Fig. 11g).
However, an improvement in the sample intake process is also achieved simply by the shaking process during the opening of the sampling chamber and/or afterwards, whereby the side edges remain in their original configuration (i.e. without a cutting edge).

Fig. 11d shows the closed sampling chamber in which the sample is located. During the cutting process, it has proven advantageous to move the cutting sleeve 78 in the distal direction approx. 2 mm beyond its end position shown in Fig. 11d and then to return the cutting sleeve to its end position another 2 mm. This scissor effect reliably cuts off any fibers that may not have been severed yet, which leads to a further improvement in the sample quality.

Fig. 13 shows the drive and installation of the vacuum/pressure generating device 5 (view from behind, i.e. against the Z-axis, housing cover and housing base are omitted).

In the upper, rear, right area, the vacuum/pressure generating device 5 is arranged as a piston/cylinder unit 69. It consists of a syringe body 52 with a threaded spindle 53 arranged therein, to the end of which facing the syringe base 51 a piston 54 with sealing elements - as is generally known for syringes - is attached (Fig. 14a - 14d).

At the end of the syringe body 52 facing the base block 8, a threaded spindle nut 48 with a gear 55 formed on the circumference is arranged on the threaded spindle. The threaded spindle nut has one or more threads. The threaded spindle 53 works together with the threaded spindle nut 48. The spindle has a pitch of approx. 5 mm per thread, so that with each revolution the piston is moved by the spindle drive by a precisely defined amount out of the syringe body, i.e. away from the syringe base 51, or towards the syringe base, depending on the direction of rotation. The gear ring 55 arranged on the circumference of the threaded spindle nut meshes with the drive pinion 56, which is attached to the output shaft of the DC gear motor 58. The output shaft of the DC gear motor 58 is mounted in the base block 8; for this purpose the

. 24

Output shaft inserted into the cross plate 59 of the base block. If the DC gear motor 58 is activated, the piston is moved towards the syringe base or towards the base block 8, depending on the direction of rotation. A high-speed DC motor is also used as the drive motor, followed by a planetary gear with a high reduction ratio. It corresponds to the motor for the clamping device already described. A counting device is therefore also attached to the distal side of the DC gear motor, which consists of a two-armed impeller 131 and a photocell mounted on the motor side. The counting device is connected to the programmable microprocessor, so that the function of the vacuum/pressure device can be controlled via the number of revolutions, in that the functions can be called up after determining an initial value using programmable or programmed specifications.
The piston 54 is designed as a syringe piston in a known manner. The syringe body, a cylinder with a base, is made of plastic and is transparent.

In order to prevent the threaded spindle 53 from twisting when the threaded spindle nut is driven, the two opposing surfaces 60 of the threaded spindle are flat (Fig. 14d). The threaded spindle is inserted into the insert element with its free end. The distance between the surfaces of the threaded spindle corresponds to the width of the U-shaped insert element 62 of the base block 8. There is only a small amount of play between the U-shaped cross section of the insert element and the spindle surfaces on both sides. The threaded spindle nut is supported on the base block.
In order to prevent the syringe body 52 from slipping out when the threaded spindle nut is turned, the contact surface on the base block 8 is slightly conical downwards.

The nozzle 63 of the syringe body 52 is inserted into the passage 16 of the housing end cover 7 in such a way that the syringe body is held in an approximately horizontal position.
In order to make it easy to turn the threaded spindle, the threaded spindle nut with gear ring has a chamfer 66 of approximately 1.5 mm on the side facing the base block. In addition, since the surface of the rib 59 on the base block 8, which interacts with the chamfer 66 of the threaded spindle nut 48, is inclined from top to bottom, the vacuum/pressure generating device is pulled downwards during operation. To generate a sufficient vacuum of approx.

200 hph in the sampling chamber, for example, with a biopsy needle length of approx. 250 mm and an inner diameter of the biopsy hollow needle between 3 and 5 mm, a syringe body for 20 ml with a length of approx. 90 mm is used. In order to be able to use the syringe body as a pressure generator, after about ³ A of the length, corresponding to the stroke for generating the vacuum (position according to Fig.

11b) a ventilation hole 67 of approximately 1.5 mm is provided. If the syringe piston is moved beyond the ventilation hole 67 (Fig. 14c) - when the vacuum is no longer required - the vacuum previously built up in the biopsy needle is relieved by supplying air (atmospheric pressure) via the ventilation hole 67. If the direction of rotation of the gear motor is then reversed, the vacuum/pressure generation device in the system will build up excess pressure by moving the piston in (towards the base of the syringe), which causes the tissue sample to be ejected after the sample removal chamber is opened. To prevent the tissue sample from being accidentally ejected by tapping the program button 89, a delay circuit is integrated into the control system which only triggers the process after approximately 1.2 - 1.5 seconds of pressing. The sample may only be ejected after the biopsy needle has been removed from the tissue, which is ensured in this way. Furthermore, the compressed air not only cleans the sample collection chamber, but also the interior of the biopsy needle. The plug that narrows the needle cavity makes it difficult or even completely impossible for tissue particles to enter the biopsy needle cavity. The narrowing of the needle cavity by the plug 79 increases the pressure in the sample collection chamber and thus improves the ejection of the sample, especially when the sample collection chamber is half open. When using the biopsy device, it is recommended to use a specially designed coaxial cannula that is tailored to the needs and requirements of the device. It must contain appropriate devices that prevent air from entering and prevent or prevent tissue fluid from escaping; it must also be easy to insert into the tissue.
The operation of the biopsy device is explained in more detail below:
The following functions can be distinguished in terms of their sequence, which run largely automatically after initiation:

a) Starting and setting the home position

b) Tensioning the biopsy needle and shooting it into the tissue

c) Cutting out the sample from the tissue (sampling)

d) Taking the sample after the biopsy needle has been removed from the tissue
was taken.

a) Starting and setting the home position

The removable insert element 20, consisting of vacuum

/Pressure generating device, elastic connecting element and

Biopsy needle carrier with needle and cutting sleeve and other elements connected to it, as well as a guide roller 81 placed on the needle, is delivered in sterile packaging. The removable elements (see Fig. 2) are held by an insertion aid, which is removed after insertion into the handpiece. This insertion aid 104 has two holding pieces for gripping on the top as well as tabs 108 for holding the biopsy needle carrier 37 and the vacuum/pressure generating device. To fix the position of the vacuum/pressure generating device (parallel to the biopsy needle carrier), a pin 110 is provided for the tab holder, which is inserted into the ventilation hole.
The piston 54 in the syringe body 52 is slightly raised (1-2 mm) from the syringe base when delivered, the sampling chamber 71 of the biopsy needle 2 is open so that a visual inspection of the sampling chamber can be carried out before insertion. After opening the housing cover 10, the biopsy needle carrier, including the biopsy needle 2, cutting device 3 and other connected parts, such as the vacuum/pressure generation device 5 connected to the connecting element 4, is inserted into the connecting elements provided on the handpiece (see Fig. 2). During the insertion process, care must be taken that the gear 74 engages with the teeth of the toothed roller 23; the cutting sleeve is inserted from above into the U-shaped holder 36, at the same time the tabs 40 of the clamping slide are inserted into the recesses 77 of the carrier element; the guide roller 81 is inserted into the passage 13 so that the flanks 101 and 102 enclose the housing end cover 6. The cutting sleeve is mounted in the guide roller so that it can be moved longitudinally and rotated freely; however, the guide roller itself can no longer be moved relative to the cutting sleeve after it has been inserted into the housing end cover. The vacuum pressure generating device is then inserted into the upwardly open insert element 62 of the base block 8 with the free end 61

and on the other hand, it is inserted into the U-shaped, upwardly open passage 16 with the nozzle 63. The nozzle 63 is located above the switching pin 19. Since the insert element on the base block side has a clear width that just allows the threaded spindle, which has surfaces 60 on both sides, to be inserted, the threaded spindle is held in the insert element so that it cannot rotate. The gear ring 55 of the threaded spindle nut 48 engages in the output pinion 56 of the gear motor after insertion. The distance between the base block on the one hand and the housing end cover 7 on the other hand is kept such that the syringe body 52 with the threaded spindle nut 48 placed on the syringe body just finds space. The unit of syringe body and attached gear is therefore held in such a way that it cannot be moved axially.

' After insertion, the vacuum pressure generating device is parallel to the

Biopsy needle carrier; the connecting element describes an arc of approximately 180 °.

It should also be noted that the insertion takes place when the clamping slide is not tensioned; this means that the gear 74 engages the right-hand end of the toothed roller when the sampling chamber is open (Fig. 3). After correct insertion, the housing cover can be closed.

To make the insertion process easier, the described insertion aid can be used. However, the insertion can also be carried out without an insertion aid. When the housing cover is closed, the nozzle 63 is pressed downwards and the microswitch is actuated via the switching pin 19 built into the housing end cover. This activates the electrical system, which is indicated by the flashing of the reset diode (yellow) 91 on the front of the handpiece. The reset diode flashes yellow, which means that the positioning of the individual elements, i.e. the insertion process, is not yet complete; the DC gear motor 21 must first close the sampling chamber 71 with the cutting sleeve 3 (the sampling chamber was partially open when it was inserted). This is done by turning the threaded sleeve connected to the cutting sleeve. The cutting sleeve moves to the left until the gear 74 comes to rest near the inside of the holder 36. The plastic disk 78 rests against the holder 36 (inside) after the sampling chamber has been closed. During this process or before or after this, the DC gear motor 58 brings the syringe piston 54 into contact with the syringe base 51. In this phase, the microprocessor counters for the movement of the needle/cutting sleeve and the vacuum/pressure generating device are also reset to

Set to zero. From this basic setting, the programmed movement sequences are carried out via the counter device arranged on the two motors. After the starting positions for the vacuum/pressure generating device and the biopsy needle/cutting sleeve have been reached, the tension diode 94 (yellow) and the sampling diode 92 (green) light up, the reset diode goes out.
b) tensioning the biopsy needle and shooting the biopsy needle into the tissue

The operator must decide in this phase whether he wants to initiate the tensioning of the tensioning slide or take a sample, e.g. after previous shooting, another tissue sample. If the operator presses the

&igr; tension button 90, the tensioning of the tensioning slide is initiated; the tensioning diode

flashes yellow, the sampling diode (green) 92 goes out. By pressing the tension button (due to the delay circuit, the button must be pressed for approx. 1.2 - 1.5 seconds), the electric DC gear motor 21 receives power and the DC gear motor drives the toothed roller 23. The gear 74 meshing with the toothed roller 23 rotates the spindle shaft and at the same time the cutting sleeve 3 connected to it. Since the spindle nut 75 is pressed into the biopsy needle carrier 37 and the gear 74 is supported via the plastic disk 78 on the holder 36, which is firmly connected to the housing via the base block 8, turning the threaded spindle sleeve 73 causes the biopsy needle carrier to be moved to the right. At the same time, the »910 biopsy needle 2 connected to the biopsy needle carrier via the bearing element 49 is moved along, which causes the biopsy needle tip to move into the cutting sleeve. The biopsy needle carrier 37 is moved to the right via the recess/tab connection of the clamping slide against the action of the spiral spring 31 until the lever 33 of the locking element is pressed into the recess 82 of the clamping slide by the spring 34. The clamping slide is locked in this position. The gear motor receives the control command that the locking position has been reached, e.g. via a photocell embedded in the sliding surface of the cover plate, which interacts with the retracted biopsy needle carrier; or via the microprocessor which, on the one hand, compares the actual number of revolutions with the entered target number that was programmed beforehand; the direction of rotation of the motor is reversed and the cutting sleeve is turned back to the right by the amount by which the cutting sleeve

V«·

by moving the clamping slide and the biopsy needle had moved beyond the biopsy needle tip. At the end of this step, the cutting sleeve closes the sample removal chamber completely (Fig. 11d), as at the beginning of the clamping process. The locking diode 95 lights up green; the flashing of the clamping diode 94 goes out. In order to reduce the frictional force between the gear and the support element during the clamping process, an additional plastic disk 78 is arranged between the gear 74 and the holder 36.

Now the biopsy needle of the biopsy device is inserted into a previously placed coaxial cannula, for example. The proximal end of the placed coaxial cannula contains a

f Seal dimensioned to cover the space between cutting sleeve and cannula

on the one hand seals, and on the other hand allows the biopsy needle with cutting sleeve to be easily inserted. The sealing ring prevents air from being sucked in from outside via the space between the cannula and cutting sleeve. The sealing ring also prevents fluid (cytological material) from escaping after the biopsy needle has been inserted or shot in. This virtually eliminates the possibility of contamination of the disinfected handpiece; on the other hand, the flank 101 of the sterile guide roller 81 prevents contamination of the sterile cannula from the handpiece. The biopsy needle tip is guided to the tumor in the cannula and, once correctly positioned, shot into the tumor.

' The shot is fired by pressing the actuation button 88. Pressing this button results in the clamping slide being released by pivoting the double-armed lever 33 about the axis 35. The clamping slide is thrown to the left by the action of a spring. The microprocessor is informed of the firing of the shot and the new position of the needle by, for example, an integrated photocell. The sampling diode lights up green, the clamping diode lights up yellow.

c) Cutting out the sample from the tissue

By pressing the program button 89 again, the sampling process is released; the sampling diode 92 flashes green. First,

SV··.no .-&ngr;-

the DC gear motor 58 of the vacuum/pressure generating device is activated. The piston of the vacuum/pressure generating device is moved in the direction of the base block, i.e. away from the syringe base, until it reaches a position shortly before the ventilation hole 67 is exposed (Fig. 14b). The vacuum in the system is generated. After reaching its end position, the system activates the motor 21, the cutting sleeve which closes the sampling chamber is opened via the gear/spindle drive. During the opening process, the negative pressure in the system sucks the tissue and any cytological fluid (cytological material) into the sampling chamber one after the other. Cytological fluid will also flow into the biopsy needle cavity and into the vacuum/pressure generating device due to the vacuum. It has proven to be advantageous that the plug (79) directs the negative pressure primarily to the lower area, the lower side, of the sampling chamber and the plug 79 makes it difficult or even impossible for the tissue to penetrate the biopsy hollow needle. If the sampling chamber is completely open so that the sample can penetrate the sampling chamber with the help of the vacuum applied, the biopsy needle is briefly moved back and forth, about 5 times, in a range of about 2 mm. This is done by the microprocessor giving the command to open further via the drive motor 21 despite the sampling chamber being open; however, this does not work because the collar 127 prevents the cutting sleeve from being moved further to the right. The threaded spindle/threaded spindle nut and the

' Biopsy needle carrier element, however, the clamping slide is moved to the distal side by

approx. 2 mm and the short spiral spring is compressed. The microprocessor control reverses the direction of rotation of the drive motor after a predetermined number of revolutions, which corresponds to the distance of 2 mm. The tensioning carriage is returned to its original position by the spiral spring and the motor. The drive motor is then reversed again and the tensioning carriage is again pulled against the effect of the short spiral spring; after the tensioning distance has been reached, the reversal takes place and so on. This forward-backward movement can be repeated as often as desired, depending on the programming. In general, 5 cycles are sufficient for this movement control to use the sharpened long sides of the sample extraction chamber to cut the tissue into the sample area, even with hard tissue samples, by separating the tissue lying on the side.

To completely retract the sample collection chamber and thereby achieve an improved filling level in the sample collection chamber. After this shaking movement of the biopsy needle, the gear motor 21 is reversed and the sample collection chamber 39 is closed by rotating the cutting sleeve, whereby the cutting edge 72 of the cutting sleeve 3 separates the tissue during the closing process. It goes without saying that by making appropriate structural changes or appropriate controls as well as additional electrical elements, the shaking movement for separating the lateral sample edges can also take place while the cutting sleeve is being opened.

During the closing process, the cutting sleeve is moved forwards towards the needle tip by approx. 2 mm beyond its closing position. This ensures that the tissue fibres are severed with certainty. The cutting sleeve is then moved back by 2 mm to the closing position. The control is carried out by the microprocessor,

looo in which the target values are stored and which the microprocessor compares with the measurement data (counting data) and thus controls the processes. Due to the special design of the sampling chamber and as a result of the applied vacuum, the tissue sample is held in the sampling chamber in a rotationally secured manner, so that the tissue sample is not twisted or twisted by the longitudinally movable cutting sleeve 3 surrounding the biopsy needle on the outside, as described. After the sampling chamber is closed, the DC gear motor for the vacuum generation unit 5 is activated. The piston 54 is first moved back until the piston reaches the

w The ventilation hole is cleared (Fig. 11c). After the vacuum in the system has been reduced, the

Push the piston towards the bottom of the syringe until the ventilation hole

loio is closed to prevent the outflow of body fluid (cytological fluid). This brief opening of the ventilation hole is in the range of fractions of a second to prevent fluid from escaping. The flashing of the sample collection diode 92 goes out. The ejection diode 93 lights up yellow. The biopsy needle with the sample chamber closed is pulled out of the cannula.

d) Taking the sample after the biopsy needle has been removed from the
Tissue was taken

After removing the biopsy unit and providing a vessel for receiving the tissue sample and liquid, the program button 89 is pressed again and the ejection diode 93 begins to flash. Due to the delay circuit for safety reasons, the program button must be pressed for approx. 1.2 - 1.5 seconds before the process is started. First, the gear motor 21 of the cutting sleeve is operated to open the sample removal chamber approximately halfway. Then the DC gear motor 58 of the vacuum/pressure generation device is activated. The direction of rotation of the

DC gear motor 58 remains and the threaded spindle 53 with piston moves towards the syringe base, so that an overpressure is now created in the system. The ► 1030 piston is advanced to the piston base, the drive motor 58 is deactivated. The gear motor 21 moves the cutting sleeve above the sampling chamber further back after the piston has reached the piston base. As a result of the overpressure built up in the system, the sample is pressed out under pressure into a waiting laboratory vessel even when the sampling chamber is half open, at the same time the cavity of the vacuum/pressure generating device, the biopsy needle and the sampling chamber are freed of tissue particles and fluid. The sample is ejected when the sampling chamber is approximately half open because this ensures that the tissue sample is ejected and the tissue sample does not fall back into the sampling chamber due to premature reduction of the overpressure. The narrowing of the biopsy needle cavity by the plug 79, which prevents tissue from entering

^ the biopsy needle cavity has been made difficult or even prevented, is shown in the

Sampling is particularly advantageous because the narrowed cross-section increases the ejection pressure. The best ejection results were therefore achieved with the sampling chamber half open; i.e. the cutting sleeve exposes half of the sampling chamber. The excess pressure also forces the tissue fluid out of the sampling chamber and cleans it.

Once the sample collection chamber is fully opened, the sampling and cleaning is complete and the ejection diode goes out. The reset diode 91 lights up yellow. If no further sample is to be taken, the housing cover is opened and the removable element 20 is removed. When the housing cover 10 is opened, the system is deactivated via the microswitch 18. However, if another sample is to be taken from the same tissue environment, press

the operator presses the program button 89 and the reset diode 91 begins to flash. The basic setting of the vacuum/pressure generating device, such as the cutting sleeve, takes place again as described. After completion of the process, the reset diode 91 goes out and the sample removal diode (green) and the tension diode (yellow) light up. It is now up to the operator again whether he wants to cut out another tissue sample from the same bullet hole - in this case he presses the program button 89 - or whether he wants to make another shot by tensioning the biopsy needle - in this case he presses the tension button 90. Depending on the choice, the further process steps run in the order already described. The process can be repeated as often as desired. After completion, the operator only has to

)t decide whether to take another sample or to stop the sample collection

is completed and the housing cover is opened.

If it is necessary to take the sample from a location on the tumor that is not directly above or at the sampling chamber after injection, e.g. to the side of it, the position of the sampling chamber 71 can be rotated using the knurled screw 80. So that the operator can recognize this radial position of the sampling chamber, a marking in the form of a notch 119 is made on the knurled disk, which points upwards when the opening of the sampling chamber is facing upwards. In the position set, the biopsy needle is fixed by the surfaces of the polygon 50 and the elastic forces in the carrier part. The process of taking the sample is the same as already

&psgr; described.

After the biopsy has been completed, the cover has been released and the exchangeable element 20 (vacuum/pressure device, biopsy needle/cutting device with all elements arranged on it) is removed upwards. In order to make it impossible to open the housing when the clamping slide is tensioned, a safety wing 84 is arranged on the biopsy needle carrier, which rests against the left front surface 85 of the locking device when tensioned. The locking device, which can be moved in the X-axis, can therefore no longer be moved to the left into the open position and the nose 12 can therefore no longer be removed from the recess 45. Conversely, the housing cover cannot be closed if the carrier unit was inserted when tensioned, since the safety wing prevents the latch from entering the space provided for it.

can be inserted. The surface 85 of the latch abuts the safety wing. The battery charging diode 96 is switched off as soon as the housing cover is opened. When the cover is closed and the insert element 20 is inserted, the battery charging diode indicates whether there is sufficient energy available.

In principle, it is conceivable that all steps for taking a sample and clamping the slide, etc., are controlled individually by hand by activating and deactivating the two gear motors. However, it is advisable that individual steps of the process are combined and run automatically and only the initiation of the next step is started by pressing a switch. This semi-automatic method, as described above, has proven to be

proved particularly beneficial .

Basically, two methods are conceivable for recording the actual values for comparison with the target values. One method is based on measuring the

lioo Length displacement of the threaded spindle when pulling out or pushing in as well as measuring the axial displacement of the cutting sleeve or the biopsy needle carrier. In order to record these changes, photocells or microswitches are arranged inside the housing, in particular on the extension of the base block 8. When measuring the change in connection with a photocell, a positioning finger 103 is additionally placed on the cutting sleeve, while in the case of the threaded spindle of the vacuum/pressure generating device, the

) of the piston unit can be used as a measuring point. If the front edge of the biopsy needle carrier is used as a measuring point with a photocell, no additional positioning finger is required. The

mo embedded photocells are covered with suitable, transparent material to prevent possible contamination. The positioning finger 103 passes through a slot in the biopsy needle holder. At appropriate points on the extension 46 of the base block 8, recesses 107 are provided in which photocells or microswitches are installed, which are either connected to the free end 61 of the

into the piston spindle, with the positioning finger or the biopsy needle carrier edge 120 (Fig. 15). These signals (actual value) are processed in the electronics and form the control signals.

. 35

The other system is based on measuring the number of revolutions of the DC geared motors, converted into units of length, which is particularly useful when the changes are made using the geared motors. A sensor is placed on the shaft of the DC motor, which interacts with a photocell placed on the housing of the DC motor. This sensor consists (see Fig. 3) of a two-armed impeller 131 and a photocell connected to the motor. These sensors on the two drive motors supply the counting pulses for the photocells, which pass them on to the programmable microprocessor, which compares this detection data with the previously stored specifications and thereby triggers the control pulses. Since the DC motors rotate at a speed of approx. 10,000 - 12,000 rpm, depending on the load.

work and on the other hand the downstream planetary gear on the output side, which interacts with the spindle drive, reduces the number of revolutions considerably, this enables precise longitudinal control. The longitudinal displacement by the spindle drives is proportional to the number of output revolutions, always an equal amount and the number of revolutions is therefore sufficient as a control signal for the accuracy of the longitudinal displacement. In order to determine the position of the cutting sleeve 3 and the piston 54 at the beginning, i.e. after inserting

^ of the removable element and closing the housing cover 10, the DC gear motor 58 rotates the piston 54 until it stops on the syringe base and the DC gear motor 21 brings the cutting sleeve drive to the zero position by bringing the gear 74 to the stop on the threaded spindle nut 75 (the threaded spindle nut 75 runs onto the gear 74). From this zero position, the control of the individual steps is then carried out via the specified/actual comparison. The necessary cables from the sensor to the electronics are housed in the housing, as is the circuit board with the electronic components (room 39).

Claims (11)

1. Biopsy device consisting of a handpiece with drive elements into which a biopsy needle is inserted, wherein a part of the part of the biopsy needle protruding beyond the handpiece can be pushed into the tissue to be examined with its sampling chamber and the tissue sample to be examined penetrates into the opening of the sampling chamber by means of negative pressure and is then separated by means of a longitudinally movable sample separation device and in a further step the sample is taken from the sampling chamber, characterized in that the two longitudinal side edges of the sampling chamber ( 71 ) are designed as cutting edges and the cutting edges are moved slightly back and forth several times during and/or after opening the sampling chamber by moving the biopsy needle, wherein the lateral cutting effect is supported in particular by the applied negative pressure in the biopsy needle and thus enables a lateral separation of the tissue and only then is the sample completely separated out by actuating the separation device. 2. Biopsy device according to claim 1, characterized in that the cutting effect with respect to the cutting edge is increased by an external pressure which emanates, for example, from the ultrasound head or another compression device. 3. Biopsy device according to claim 1, characterized in that the cutting edges ( 68 ) on the longitudinal sides of the sampling chamber are formed in that the inner radius (ri) of the sampling chamber merges into the outer radius (ra) by removing the material (T1) from the wall thickness and that the cutting edges are arranged in the region above 180° ( Fig. 11g). 4. Biopsy device according to claim 1, characterized in that the stroke for the forward and backward movement is adjustable by programming the microprocessor. 5. Biopsy device according to claim 4, characterized in that the stroke is 2 mm. 6. Biopsy device according to one or more of the preceding claims, characterized in that the forward or backward movement is generated by the controlled drive motor for the needle/cutting device pulling the clamping carriage ( 28 ) against a short spiral spring ( 124 ) arranged between the block ( 26 ) and the clamping carriage ( 28 ) and then by reversing the motor ( 21 ) the spring supports the return of the clamping carriage. 7. Biopsy device according to claim 6, characterized in that the forward/backward movement is repeated 5 times at short intervals. 8. Biopsy device according to claim 6, characterized in that the control of the drive motor is carried out by a sensor mounted on the motor, which transmits the signals to the programmable microprocessor. 9. Biopsy device according to one or more of the preceding claims, characterized in that the drive, the vacuum/pressure generating device ( 5 ) consisting of a piston-cylinder unit ( 69 ) which is arranged parallel to the biopsy needle carrier, and the drive of the biopsy needle/cutting device including the clamping device each consist of a geared motor, the direction of rotation and duration of rotation of which are controlled by a programmable microprocessor and the sensor for the respective measured values is arranged directly on the respective drive motor. 10. Biopsy device according to one or more of the preceding claims, characterized in that the triggering of the program steps "clamping" and "ejection of the sample" are called up via delay circuits. 11. Biopsy device according to one or more of the preceding claims, characterized in that during the closing process of the cutting sleeve for cutting out the sample, the cutting sleeve ( 3 ) is moved beyond the closing position approximately 2 mm in the direction of the needle tip and is then moved back by the same distance into the closing position.