The invention relates to a resectoscope of the type defined in the preamble of Claim 1.
Resectoscopes are surgical instruments used for ablation of tissue in the body. They are designed with an elongated shaft according to the endoscopic principle and allow observation of the surgical field with a lens system and the respective illumination. Resectoscopes have a carriage that is longitudinally displaceable by hand and moves a resection instrument, such as, for example, a high-frequency loop electrode or a laser fiber emitting at the distal end. Resectoscopes are used in urology, for example, to reduce the size of the prostate.
A generic resectoscope is described in DE 196 18 399 A1, where the laser fiber is secured in the receiving bore of the carriage with a thumbwheel clamped on the carriage. This ensures accurate control of the laser fiber by the carriage.
One disadvantage of this known construction is the point attack of the clamping head on the laser fiber, which is very sensitive mechanically. This results in the possibility of unreliable clamping or damage to the laser fiber.
Resectoscopes with a laser fiber mounted so that it is longitudinally displaceable are known from the documents DE 198 26 311 and DE 20 2011 051 869 U1. In addition, the documents WO 2008/133707 A1 and DE 10 2004 007 120 B3 describe possibilities for clamping laser fibers on medical instruments.
The object of the present invention is to improve the clamping device in a generic resectoscope.
This object is achieved by the features of the characterizing part of claim 1.
According to the invention, a clamping body is supported on the carriage with a region of the receiving bore moving with the carriage. However, other regions of the receiving bore are arranged in a stationary position in the carriage. The laser fiber thus passes through at least one region of the receiving bore that is stationary on the carriage and a region of the receiving bore that is movable with the clamping body.
The regions of the receiving bore are displaced relative to one another by transverse movement of the clamping body, which thus results in the laser fiber becoming stuck. The laser fiber is then acted upon by the walls of the receiving bore over a large area, so that, with secure clamping, this results only in minor loads for the sensitive laser fiber.
The kinematics according to claim 2, in which the moving region of the receiving bore is moved, so that it executes an eccentric rotation with respect to the stationary region, are advantageous. This results in a very accurate controllability of the clamping forces, in particular when the eccentricity conforms to the conditions of claim 3.
It would be sufficient if only one stationary region of the receiving bore were arranged distally or proximally from the clamping body. However, according to claim 4, stationary receiving bores are advantageously provided on both sides, leading to a particularly secure symmetrical application of the clamping forces.
The embodiment of the invention according to claims 3 and 4 offers yet another advantage. It has kinematic and structural similarities with the German Patent Application DE 10 2012 023 275 A1, which was published subsequently and has a design for fastening an electrode on the carriage. The two designs can be combined with one another, wherein only the clamping body need be exchanged to switch a resectoscope from operation using a laser fiber to operation using an electrode.
The drawings show the invention schematically and as an example, in which:
An elongated lens 5 with an eyepiece 5a arranged on the proximal end passes through the guide tube 3 and the shaft tube 2 and is arranged in such a way that the surgical field in front of the distal end of the shaft tube 2 can be observed. A lighting device for illuminating the surgical field is not shown for the sake of simplicity of the drawing.
A carriage 6 is mounted so that it is displaceably guided on the guide tube 3 with a guide bore 7 between the main body 2a and the guide plate 4. As shown in
As
The laser fiber 8 is to be moved in the longitudinal direction of the endoscope 1, i.e., in the direction of the lens 5 and/or of the shaft tube 2, by the movement of the carriage 6. Therefore, a mechanical fastening between the laser fiber 8 and the carriage 6 is required.
A cylindrical cavity 13, whose axis runs in the longitudinal direction, is thus parallel to the guide bore 7 in the carriage 6. The cavity 13 is accessible through a slot 14 at the side.
As shown by the figures, the laser fiber 8 passes through the cylindrical cavity 13 and two bores 15 and 16 in the carriage 6, which are arranged distally and/or proximally from the cavity 13, so that they are arranged to be flush with one another and in the longitudinal direction, i.e., parallel to the guide bore 7.
In the embodiment shown here, the axis of the cylindrical cavity 13 is arranged to be concentric with the boreholes 15 and 16, of which the bore 16 is shown with dotted lines in
The damping body 17 has a bore 18 in which the laser fiber 8 runs, passing through the clamping body 17 in parallel to the bores 15 and 16 but eccentrically in relation to them.
The clamping body 17 is mounted in the cavity 13, so that it can rotate about the axis, as shown in
If the clamping body 17 is rotated by 90 degrees into the rotational position shown with dotted lines, then all three bores 15, 16 and 18 are aligned as shown in
If the clamping body 17 then is rotated out of the rotational position in
In a diagram according to
Number | Date | Country | Kind |
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10 2013 018 972.1 | Nov 2013 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2014/002905 | 10/29/2014 | WO | 00 |