Surgery – Endoscope – Having auxiliary channel
Reexamination Certificate
2001-09-10
2004-03-02
Dvorak, Linda C. M. (Department: 3739)
Surgery
Endoscope
Having auxiliary channel
C600S156000, C600S158000, C606S046000
Reexamination Certificate
active
06699185
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to a medical or technical endoscopic instrument, comprising a shaft having an endoscope optical system arranged therein, which comprises a distal front face, and a working element also arranged in the shaft, wherein further the shaft serves to supply an irrigation fluid into an operation or application area.
A medical instrument of this kind is known from document DE-C-195 20 277.
By means of a medical instrument of the type mentioned at the outset, tissue in the human or animal body is treated with the working element, for example is removed, grasped and/or coagulated in minimally invasive surgery under endoscopic control with the endoscope optical system.
For treating tissue, a working element is used with at least one tool which is configured as a purely mechanically cutting tool, for example in the form of forceps jaws, or as an electrode supplied with high frequency current, with which tissue can be removed or cut or coagulated due to the action of high frequency current.
Such an instrument for medical purposes is known for example from the German catalogue of the firm Karl Storz GmbH & Co., Tuttlingen, “Karl Storz-Endoskope”, Vol. Urology, page RES-SC 6 A, Edition 1995.
The instrument known from the German catalogue mentioned at the outset is a resectoscope, where the various working elements having cutting electrodes, coagulation electrodes or curettes can be inserted with which the corresponding treatment can be carried out. The invention however is not limited to a resectoscope.
Endoscopic instruments of this type are also known for technical purposes, which are used in difficultly accessible spaces in machines, motors or the like.
Since bleeding naturally occurs when removing tissue, such instruments provide for the introduction of an irrigation fluid through the shaft into the operation area to irrigate away the blood which obstructs the view. The irrigation fluid is passed through the shaft from the proximal end to the distal end, where it exits from the distal end to irrigate the operation area in the region of the tool. Normally, an excess cross-section remaining in the shaft when the endoscopic optical system and the working element are inserted is usable as an irrigation cross-section. The irrigation fluid therefore flows in the shaft along the endoscope optical system and passes its front face.
The problem results with the irrigation fluid running along the endoscope optical system, that a dead space of flow is formed distally in front of the front face of the optical system, which is the light emission and the light inlet end of the endoscope optical system. This means that the irrigation fluid during irrigation does not reach distally in front of the front face of the optical system. Rather, blood and pieces of tissue can collect there, which are not reached by the irrigation fluid and are not washed away. However, the blood and tissue pieces collecting in front of the front face are non-transparent and thus obstruct visual control with the endoscope optical system. The problem of a dead space in the flow arises particularly for optical systems with a straight-forward view or oblique-forward view, whose front faces are nearly perpendicular to the flow direction of the irrigation fluid, i.e. when a perpendicular line to the front face makes an angle of about 0° to about 20° with respect to the flow direction.
The additional problem arises in instruments for treating tissue with high frequency current that small gas bubbles form when treating the tissue with high frequency current. These collect in the dead space of flow in front of the distal front face of the optical system and adhere to the front face and are not caught by the irrigation fluid and washed away due to the formation of the dead space of flow.
The instrument known from document DE-C-195 20 277 mentioned at the outset comprises a shaft, an endoscope optical system received therein and a working element also received in the shaft. In the remaining space between the shaft, the endoscope optical system and the working element, an irrigation fluid is conducted from the proximal end to the distal end. Flow-influencing means are provided for the purpose that the irrigation fluid reaches in front of the front face of the endoscope optical system. The flow-influencing means comprises an opening in the shaft and an outer shaft arranged about the shaft and spaced therefrom, wherein in the space between the outer shaft and the shaft, a vacuum is applied. The irrigation fluid conducted through the shaft to the distal end is sucked through the opening into the space between the outer shaft and the shaft, whereby the irrigation fluid is conducted along the front face of the endoscope optical system.
The object of the present invention is to provide an instrument of the type mentioned at the outset in which the handling of the instrument is improved.
SUMMARY OF THE INVENTION
According to the present invention, this object is achieved with respect to the instrument mentioned at the outset by an endoscopic instrument, comprising a shaft, an endoscope optical system arranged in said shaft, said endoscope optical system having a distal front face, and a working element arranged in said shaft, wherein said shaft serves to supply an irrigation fluid into an operation or application area, wherein flow-influencing means are provided such that said irrigation fluid reaches in front of said front face of said endoscope optical system, and wherein said flow-influencing means are provided on said working element.
The instrument according to the present invention, thus, provides suitable means for influencing the flow of irrigation fluid in the region of the front face such that at least a portion of the irrigation fluid is deflected in front of the front face and a fluid flow occurs in the dead space of flow formed in conventional instruments in front of the front face. Thus, the blood, tissue pieces and optionally gas bubbles which can collect in front of the front face and obstruct the view are caught by the irrigation fluid and washed away. The invention avoids the collection of non-transparent fluids or tissue pieces, in particular for endoscope optical systems whose front face is disposed perpendicularly or nearly perpendicularly to the flow direction and where a dead space of flow forms to greater extent. The flow-influencing means can be configured and arranged such that the otherwise substantially laminar flow in the region of the end face of the optics is converted into a turbulent flow and/or the flow direction of the flushing fluid can be deflected such that a flow component along the front face of the optical system is formed. In both cases, it is guaranteed that the front face is sufficiently irrigated with the irrigation fluid. According to the invention, the flow-influencing means are provided on the working element. The advantage is that the flow-influencing means can be configured and positioned such that they do not obstruct the view. Since the working elements are often arranged to be axially shiftable relative to the endoscope optical system, this configuration opens up the very advantageous possibility of providing different flow conditions by moving the working element back and forth to efficiently deflect the flushing fluid in front of the front face.
The object underlying the invention is thus completely achieved.
In a preferred embodiment, the flow-influencing means are configured as flow obstructions which cause a swirling of the irrigation fluid in front of the front face of the optical system.
The advantage is that a swirling of the irrigation fluid in front of the front face of the endoscope optical system effectively causes a mixing of the irrigation fluid with the blood collected in front of the front face and results in a very effective removal of adhering gas bubbles or pieces of tissue.
In a further preferred embodiment, the flow-influencing means are configured as flow deflection means which generate a flow component along the front face
Dittrich Horst
Doll Frank
Gminder Frank
Dvorak Linda C. M.
Karl Storz GmbH & Co. KG
Ram Jocelyn
St. Onge Steward Johnston & Reens LLC
LandOfFree
Medical endoscopic instrument does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Medical endoscopic instrument, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Medical endoscopic instrument will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3232786