Laparoscopic radiofrequency surgical device
Technical field
The invention belongs to surgical devices; more specifically, it is a laparoscopic radiofreguency surgical device which is particularly suitable for liver resection.
Current state of the art The liver is currently the mcst frequent place cf occurrence of secondary tumors -metastases. Until recently, liver resections have been considered as necessary to be performed with open surgery. The development of new surgical devices, however, makes it possible to use laparoscopic surgical devices even in this kind of treatment.
The known laparoscopic surgical devices consist of a body forming a handle, on which control elements such as knobs, buttons and levers are located, and of a tube part firmly connected to the body. The tube part contains the tool itself with needles. In the resting position, the needles are covered with the tube part of the device, whereas in the working position they protrude from the tube part.
The above-described layout of known laparoscopic surgical instruments, which, in additicn to that, are led through a narrow trocar during use, limits their access only to those liver segments which are directly accessible by the orifice of the tube part. The parts of the liver not accessible by the orifice of the tube part in this sense cannot be treated using known laparoscopic devices. In such cases, open surgery must be applied. This limitation of use is the main disadvantage of the known laparoscopic surgical devices for liver resection.
Principle of the invention The purpose of the invention is to create a laparoscopic radiofrequency surgical device for liver resections that can also be used for liver segments or parts inaccessible for the existing laparoscopic devices, i.e. mainly for the so-called posterosuperior liver segments marked as S7 and S8.
Accordingly, the present invention provides a laparoscopic radiofrequency surgical device for liver resections as set forth in the claims.
The aforementioned goal can be achieved with a laparoscopic radiofrequency surgical device, particularly suitable for liver resections, with a body forming a handle, with a long tube firmly connected to the body and with needles, which is based on an invention whose principle is that the long tube has another movable short tube attached to its end. This short tube contains the needles and has a mechanical drive for adjusting its angular position against the long tube.
Tt is of advantage to make the movable connection between the short and the long tube pivoted.
For easy control of the mechanical drive for the adjustment of the angular position of the short tube, the device is eguipped with a control element in the form of adjusting knob no. 1, which is located on the handle. This first adjusting knob has a worm gear inside the device body which is connected to the short tube at a point perpendicular to the short tube's axis in a distance from the axis of the pivot pin via a short tow bar and a long tow bar.
For easy control of the needles, the device has a second adjusting knob which is located on the upper part of the body.
This second adjusting knob has a bevel gear inside the device body, which is connected to a screw via a rotary tow bar in the long tube and via a flexible coupling. The screw is pivoted in the short tube and has a sliding nut attached, to which needles are fastened.
Tn addition to the advantages resulting directly from the above-mentioned purpose of the invention, the laparoscopic radiofrequency surgical device according to this invention is easily controllable using mechanical means only, with both right and left hand. For liver segments 32, 33, S4a, 35, and S6, which can be treated with the existing laparoscopic devices, the laparoscopic radiofreguency surgical device according to this invention will improve the handling and accessibility thanks to the adjustability of the angular position of the short tube against the long tube.
Additionally, the present invention may be defined in terms of
the following statements:
1. Laparoscopic radiofrequency surgical device, particularly suitable for liver resection, with a body (1) forming a handle, with a long tube (2) firmly connected to the body (1), and with needles (4), whose principle is that the long tube (2) has another movable short tube (3) attached to its end.
This short tube (3) contains the needles (4) that can be shifted and it has a mechanical drive for adjusting its angular position against the long tube (2) 2. Laparoscopic device according to 1, where the short tube (3) is connected to the long tube (2) via a pivot pin (5) 3. Laparoscopic device according to 1 or 2, where the mechanical drive for the adjustment of the angular position of the short tube (3) is equipped with a control element in the form of adjusting knob no. 1 (6), which is located on the handle part of the body (1) 4. Laparoscopic device according to 3, where the first adjusting knob (6) has a worm gear (11) inside the body (1), which is connected to the short tube (3) at a point perpendicular to the short tube's (3) axis in a distance from the axis of the pivot pin (5) via a short tow bar (12) and a long tow bar (13) going through the long tube (2) 5. Laparoscopic device according to any of 1-4, where the device is eguipped with a second adjusting knob (7) located on the upper part of the body (1), which serves for the pushing in and out of needles (4) 6. Laparoscopic device according to 5, whose second adjusting knob (7) has a bevel gear (14) inside the body (1), connected via a rotary tow bar (15) in a long tube (2) and via a flexible coupling (16) with a screw (17) pivoted in a short tube (3), which has a sliding nut (18) attached, to which needles (4) are fastened.
Overview of illustrations in the drawings An example implementation of the laparoscopic radiofreguency surgical device for liver resection according to this invention is shown in the attached drawings, where fig. 1 shows an axonometric view of the device in the basic position, fig. 2 shows the same device in the working position with the short tube turned and the needles pushed out, fig. 3 shows the layout of control mechanisms inside the device body, and fig. 4 shows a detail of the pivoted connection between the long and the short tube in an axial section.
Example implementation of the invention The laparoscopic radiofrequency surgical device for liver resection according to fig. 1 and 2 has a hollow body 1 whose bottom part forms a handle. A long tube 2 is firmly connected to the body 1 and a short tube 3 is attached to the end of the long tube by means of a pivot pin 5. The pivoted connection may also be different, e.g. there may be a shaped connection between the surfaces of tubes 2 and 3. In this exanple, tubes 2 and 2 have a circular cross-section, but they can also have an oval, square, or other cross section. On the body 1 there are control elements in the form of adjusting knobs 6, 7. The first adjusting knob 6, which is located on the handle of the body 1, serves for manual adjustment of the angle between the long and the short tube, 2 and 3. The second adjusting knob 7, which is located on the upper part of the body 1, serves for manual pushing of the needles 4 in and out of the short tube 2 The body 1 is symmetrical with respect to the longitudinal plane of the device and the axes of adjusting knobs 6, 7 lie in this plane. This means that the device can be held both in the right and in the left hand and the adjusting knobs 6, 7 can be turned with the fingers of the right or left hand. In the lower part of the handle there is an opening 8 for the cable connecting the needles 4 with a radiofrequenoy current generator.
Inside the handle in the hollow part of the body 1 (fig. 3) there is a tensioning segment 9 and an idle pulley 10 for the cable which goes from the input opening 8 through the hollow part of the body 1,, the long tube 2 and the short tube 2 to the needles 4.
In the hollow part of the body 1, there is also a worm gear 11 which is connected to the first adjusting knob 6. The worm gear II has attached a short tow bar 12, to which a long tow bar 13 is connected, which then goes through the long tube 2 and is attached to the short tube 3 at a point perpendicular to the axis of the short tube 3 in a distance from the axis of the pivot pin 5 connecting the short tube 2 with the long tube 2.
The hollow part of the body 1 also contains a bevel gear 14 which is connected to the second adjusting knob 7 and drives the rotary tow bar 15, which goes through the long tube 2. At the pivot pin 5, the rotary tow bar 15 is connected to a screw 17 pivoted in the short tube 2 via a flexible coupling 16. The screw 17 has a nut 18 sliding in the short tube 3. The needles 4 are fastened to the nut 18. In the described example, the flexible coupling 16 consists of a steel wire. However, it may consist of other flexible parts, e.g. plastic ones.
In the basic position, the short tube 2 of the laparoscopic radiofrequency surgical device is coaxial with the long tube 2. After the short tube is inserted into the abdominal cavity through a trocar, the first adjusting knob 6 can be turned in the direction of Cl with the fingers of the hand holding the device in order to set the required angle between the short and the long tube, 2 and 2. The turning of the first adjusting knob 6 is transferred to the short tube 2 via the worm gear II and via the tow bars 12 and 13. In doing this, the rotary movement of the first adjusting knob 6 is converted into a linear movement of the long tow bar 13 in the long tube 2. The first adjusting knob 6 has an angular scale around it on the device body 1. The rotation of the short tube 3 against the long tube 2 is enabled thanks to the connection between the long tow bar 13 and the short tube 2 The flexible coupling 16 flexibly adapts to the displacement of the short tube 2-The needles 4 are pushed out of the short tube 2 by rotating the second adjusting knob 7 in the direction of C2. The second adjusting knob 2 also has an angular scale around it on the device body 3. The rotary movement in the direction of 02 is transferred to the screw 17 and the nut 18 via the bevel gear 14, the rotary tow bar 15 and the flexible coupling 16. The nut 18 with the needles 4 is shifted through the short tube 2' which pushes the needles 4 out of the tube 3. After the needles 4 are pushed out, activating a foot switch or a switch on the body 1 (not shown) will connect them to the radiofrequency current generator via a cable. The needles 4 are repeatedly pushed into the liver segments, wherein the temperature effects of electric current are utilized to create a necrosis zone so that the tumor tissue can be removed by the surgeon. After the intervention is over, the same foot switch or the same switch on the body 1 are used to disconnect the device from the radiofrequency current generator. Then the needles 4 are pushed in by rotating the second adjusting knob 2 in the direction of 02 and the short tube 2 is rotated to be coaxial with the long tube 2 by rotating the first adjusting knob 6 in the direction opposite to that of 01. In this condition, the tool can be pulled out of the abdominal cavity through the trocar.
The construction of the tool allows for different maximum angles between the short tube 2 and the long tube 2; an angle of 60° is sufficient for practical application. It is sufficient to push the needles 4 30 mm out of the tube. If necessary, the subject device of the invention can be used without any turning of the short tube 2 This is possible if directly accessible segments of the liver are treated. The device is intended for single use after which it is disposed of. Both the long and the short tube (2 and 2) as well as the needles 4 are made of medicaf materials such as stainless steel. The body 1 including the handle and the adjusting knobs 2 are also made of materials intended for medical use; suitable are plastics approved for medical use.
Industrial applicability
The laparcscopic radiofrequency surgical device according to this invention is particularly suitable for liver resections.
More generally, the principle can be used in laparoscopic surgical devices designed for other surgical interventions in hardly accessible areas.