Endoscopic probe with reduced obstruction

This is an application for reissue of U.S. Pat. No. 10,945,587.

The present application claims priority to German Application No. 10 2017108 272.7 filed Apr. 19, 2017, the disclosure of which is hereby incorporated by reference herein in its entirety.

The present invention relates to an endoscopic probe with a shaft and a handle, which comprises a front end, a rear end and, extending between the front end and the rear end, a grip portion.

In microsurgery, for instance in neurosurgery, it is generally necessary, for example after removal of a deep-lying tumour or after treatment of an aneurysm, to view sites that lie outside the line of vision of a surgical microscope. For this purpose, endoscopic probes are then used in addition to the surgical microscope, for example endoscopic probes of the kind described in DE 10 2015 004 546 A1, U.S. Pat. No. 7,162,292 B2 and US 2011/0178395 A1.

Endoscopic probes typically have a handle, from one end of which a shaft extends, and from the other end of which a cable emerges. The challenge is to design the endoscopic probe such that, on the one hand, it is highly ergonomic and, on the other hand, it is possible to reliably avoid collision between the endoscopic probe and a surgical microscope that is used together with it.

The object of the present invention is to make available an endoscopic probe which is highly ergonomic and with which it is possible to reliably avoid collision with a surgical microscope that is used together with said endoscopic probe.

This object is achieved by an endoscopic probe according to Claim. The dependent claims contain advantageous embodiments of the invention.

An endoscopic probe according to the invention comprises a handle with a front end, a rear end with a rear end axis and, extending between the front end and the rear end, a straight grip portion with a grip portion axis. Moreover, it comprises a shaft extending from the front end of the handle and having a shaft axis and, when the rear end is designed as a cable outlet end, it has a cable emerging from the rear end. The axes are each defined by the connecting line between the centre points of the cross sections at the ends of the respective portion or of the shaft. In the endoscopic probe according to the invention, the shaft axis, the rear end axis and the grip portion axis lie within one plane. The shaft axis encloses with the grip portion axis an angle in the range of 100 to140150degrees, in particular in the range of110120to130140degrees and preferably in the range of115125to125130degrees. The grip portion axis encloses with the rear end axis an angle in the range of110130to130160degrees, in particular in the range of115145to125155degrees, and the shaft axis encloses with the rear end axis an angle in the range of3090to90130degrees, in particular in the range of 100 to 110 degrees. The angle that the shaft axis encloses with the grip portion axis can in particular be the same size as the angle that the grip portion axis encloses with the rear end axis. If present, the cable emerges from the rear end at an angle of not more than a maximum of 20 degrees, preferably not more than 10 degrees with respect to the rear end axis. In particular, the cable can emerge from the rear end in a manner parallel to the rear end axis. In the case of a cable-free endoscopic probe, the rear end can contain an antenna and/or an accumulator.

The angled arrangement of the endoscopic probe according to the invention, at the stated angles, allows the total length in the direction of the grip portion axis to be kept short and at the same time minimizes the risk of the handle, or of the rear end or cable outlet, colliding with a simultaneously used surgical microscope, while a high level of ergonomic comfort is achieved at the same time. Although an angle of 90 degrees between the shaft axis and the handle axis would be optimal in the sense of minimizing the risk of collision, it has been found that such an angle does not permit good manageability in the predominantly one-handed use of the endoscopic probe. In particular, an angle of 90 degrees adversely affects the rotation in situ and the safe insertion of the probe. The angle according to the invention, between the shaft axis and the handle axis, i.e. the grip portion axis, in the range of 100 to140150degrees, in particular in the range of110120to130140degrees and preferably in the range of115125to125130degrees, permits uncomplicated rotation of the shaft in situ and safe insertion into the site without at the same time substantially increasing the risk of collision with the simultaneously used surgical microscope. By virtue of the fact that the rear end axis is likewise at an angle, specifically in a range of between110130and130160degrees, in particular between115145and125155degrees, it is possible to avoid a situation where the rear end or the cable collides with the surgical microscope during the rotation of the shaft in situ or during the insertion of the shaft. At the same time, by virtue of the chosen angle of the rear end axis, the cable can be guided across the back of the hand such that it does not unnecessarily impede the user during the rotation of the probe in situ. The stated angles therefore characterize a particularly advantageous geometry of the endoscopic probe.

In the endoscopic probe according to the invention, the shaft can have a length in the range of 50 to 180 mm, in particular of 90 to 130 mm. This is long enough for use in microsurgical interventions, but also short enough to be able to avoid collision of the handle with the surgical microscope during the handling of the endoscopic probe.

The shaft can have diameters in the range of 3.0 to 4.1 mm, in particular in the range of 3.4 to 3.8 mm. The shaft, at least in a distal portion, can have a wall thickness in the range of 0.3 to 0.5 mm, in particular in the range of 0.35 to 0.45 mm. At a proximal portion of the shaft adjoining the front end of the handle, the shaft can have an increased wall thickness in the range of 1.3 to 1.5 mm, in particular in the range of 1.35 to 1.45 mm. The proximal portion can have a length in the range of 10 to 20 mm, in particular in the range of 13 to 17 mm. A shaft with the stated dimensions is small enough to permit a surgical intervention that is as non-invasive as possible, but also stable enough to avoid damage to the shaft during a surgical procedure. Moreover, the clear shaft diameter is large enough to permit a high image quality and a high resolution of images captured through the shaft. In particular, the interior of the shaft can then accommodate an image-conveying optics system with which object light emanating from an object observed by means of the endoscopic probe is conveyed to an image sensor arranged in the handle, which is preferably an HD sensor. Moreover, there is still enough room in the shaft to ensure that illumination light, which is emitted from a light source arranged in the interior of the handle and with which the object observed by means of the endoscopic probe is illuminated, can be guided to the observed object with the aid of an optical fibre routed through the interior of the shaft.

The handle of the endoscopic probe according to the invention can have a diameter of 18 to 38 mm, in particular of 24 to 32 mm. Moreover, the grip portion and the front end can together have a length in the range of 100 to 120 mm, in particular in the range of 105 to 115 mm. With these dimensions, it is compact enough to allow the endoscopic probe to be used together with a surgical microscope, without there being any appreciable risk of the handle colliding with the surgical microscope, but also large enough to be able to receive the necessary technical elements such as light source and sensor, but also a heat accumulator to prevent the handle from overheating at places, which would make handling uncomfortable or, in extreme cases, impossible. Moreover, the safe handling of an instrument with the described geometry likewise requires a grip or handle of the stated dimensions.

In an advantageous further embodiment of the endoscopic probe according to the invention, the grip portion of the handle, in a plane perpendicular to the common plane of the shaft axis, the grip portion axis and the rear end axis, has a cross section with a cross-sectional upper side, which faces the point of intersection of an imaginary continuation of the shaft axis with an imaginary continuation of the rear end axis, and a cross-sectional underside facing away from this intersection. The cross-sectional upper side has a central and preferably convex portion and, adjoining the central portion, two portions which are less convex or concave or which are straight and which form cut-outs from the limbs of an imaginary isosceles triangle whose apex lies centrally above the cross-sectional upper side. The isosceles triangle can in particular be an equilateral triangle. This embodiment of the grip portion of the endoscopic probe is based on the recognition that the grip portion is generally not grasped in the whole hand, and instead is often gripped with the finger tips like a violin bow in order to permit improved fine-motor handling, or lies in the crook between thumb and index finger, balanced on the middle finger and guided with the tips of thumb and index finger. The straight portions of the cross-sectional upper side form advantageous grip surfaces for gripping the grip portion with the tip of the thumb on one side and with the tips of generally at least the index finger, and possibly the middle finger, on the other side. With the aid of the straight portions serving as grip surfaces or grip structures in the grip portion, it is possible to ensure safe handling and ergonomic guiding of the endoscopic probe. The symmetry in the form of an isosceles triangle means that the endoscopic probe is suitable both for safe handling with the left hand and also for safe handling with the right hand.

The cross-sectional underside of the cross section of the grip portion can have a convexity, wherein the cross-sectional underside then has a central region with a central convexity and, adjoining the central region, portions that have a lesser convexity compared to the central convexity. In particular, the portions that have a lesser convexity or concavity compared to the central convexity can also be free of convexity and/or can extend parallel to each other. By the reduction of the convexity, and in particular if the portions of lesser convexity are formed entirely without convexity as parallel portions, relatively sharp edges can be formed at the margins of these portions and can contribute to the safe handling and guiding of the endoscopic probe.

The cross-sectional underside can additionally have a bearing surface for the middle finger. This surface can be embodied, for example, in the form of a shallow portion of the cross-sectional underside or in the form of an indent or dimple in the cross-sectional underside.

In order as far as possible not to impede the view of the distal end of the shaft, it is advantageous if the shaft is arranged at the front end of the handle in such a way that the front end, perpendicularly with respect to the direction of extent of the shaft axis, has a maximum protrusion, over the shaft, that is dimensioned such that the angle θ between an imaginary line emerging from the distal end of the shaft, extending in the plane of the shaft axis, the rear end axis and the grip portion axis and tangent to the front end of the handle is not more than 8 degrees, preferably not more than 5 degrees. There is also the possibility that the axis of the front end of the handle does not coincide with the shaft axis and that instead the two axes are at an angle to each other that is chosen such that the protrusion of the front end is compensated at the distal end of the shaft, with the result that the angle θ can be further reduced and in particular can be zero degrees.

In the endoscopic probe according to the invention, the shaft and the handle, including the connection between the shaft and the handle, can be impervious to liquid and gas, and the shaft and the handle can be made of a material that can be autoclaved. By means of this embodiment, the shaft and the handle can be sterilized in an autoclave. This embodiment is suitable in particular for endoscopic probes that have no cables. In endoscopic probes with cables, the cable and the connection between the cable and the handle are also impervious to liquid and gas, and the cable is made of a material that can be autoclaved. By means of this embodiment, endoscopic probes with cables can also be sterilized in an autoclave. The sterilizability dispenses with the need to use a drape, such that ergonomic handling is in any case maintained.

Further features, properties and advantages of the present invention will become apparent from the following description of an exemplary embodiment with reference to the accompanying figures.

An exemplary embodiment of an endoscopic probe according to the invention is explained below with reference to.shows a view of the endoscopic probe with a handle and a shaft, andshow cross sections through the shaft or handle.

In the present exemplary embodiment, the endoscopic probe comprises a handlewith a grip portion, a front endand a rear end. The grip portionextends along a grip portion axis AG, wherein the grip portion axis interconnects the centre points of the two end faces,of the grip portion. The end faceof the grip portion is adjoined by a front end, from which the shaftextends along a shaft axis AS. The shaft, which is straight in the present exemplary embodiment, has a proximal end, which adjoins the front endof the handle, and a distal end, which is remote from the front endof the handle. In the present exemplary embodiment, its shaft axis AS encloses an angle α of 130 degrees with the grip portion axis AG. However, it will be noted at this point that this angle α does not necessarily have to be 130 degrees, and instead it can lie in a range of 100 to140150degrees, in particular in a range of110120to130140degrees, and preferably in a range of115125to125130degrees. This range, and in particular the narrower of the two ranges, has proven advantageous in terms of ergonomics.

The other end faceof the grip portionis adjoined by the rear endof the handle, where a cableemerges from the handlein the present exemplary embodiment. The rear endhas a rear end axis AK, wherein the rear end axis AK extends through the centre point of the cross-sectional surface adjoining the end faceof the grip portion and through the centre point of the surface of emergence of the cable. The cablepreferably emerges from the rear endin a direction that corresponds to the direction of the rear end axis AK. However, it can in principle also emerge at a small angle with respect to the rear end axis AK, wherein the small angle is not more than a maximum of 20 degrees, preferably not more than 10 degrees.

In the present exemplary embodiment, the rear end axis AK encloses an angle β of130150degrees with the grip portion axis AG. However, it will be noted at this point that, in other design variants, the angle β can lie in the range of between110130and130160degrees, preferably in the range of between115145and125155degrees. The range of110130to130160degrees, and in particular the range of115145to125155degrees, has proven advantageous in terms of ergonomics.

The shaft axis AS, the grip portion axis AG and the rear end axis AK lie in a common plane, as a result of which the imaginary continuations of the shaft axis AS and of the rear end axis AK intersect at a point of intersection. The imaginary continuations of the two axes are indicated by broken lines in. In the present exemplary embodiment, they enclose an angle γ of80100degrees. Here too, however, the angle γ does not necessarily have to be80100degrees, and instead it can lie in a range of between3090and90130degrees,for example it can be 60 degreespreferably in a range of between 100 and 110 degrees. Said ranges for the angle γ are based on the aforementioned angle ranges for the angles α and β. By virtue of the fact that all three axes AS, AG and AK lie in a common plane, the endoscopic probe can be configured such that it can be guided equally advantageously both with the left hand and also with the right hand.

In the present exemplary embodiment, the grip portiontogether with the front endhas a length LH of 110 mm. However, it is also possible to deviate from this value. Possible lengths of the grip portionincluding the front endcan lie in the range of between 100 and 120 mm.

In the present exemplary embodiment, the shafthas a length LS of 120 mm from the proximal endto the distal end. Here too, it should be noted that, in other design variants of the endoscopic probe, the shaft length LS can have another value in a range of 50 to 180 mm, in particular in the range of 90 to 130 mm. The external diameter DD of the shaft (see also, which shows a section along the line II-II from) is 3.6 mm in a distal portionof the shaft, and the wall thickness DWD in the distal portionis 0.4 mm. In other design variants of the endoscopic probe according to the invention, the external diameter DD and the wall thickness DWD in the distal portionof the shaftcan also assume other values, wherein the values for the external diameter DD lie in the range of between 3.0 and 4.1, in particular in the range of 3.4 to 3.8 mm, and the values for the wall thickness DWD lie in the range of between 0.4 and 0.5 mm, in particular in the range of 0.35 to 0.45 mm. In a proximal portionlocated between the distal portionand the proximal endof the shaft(see also, which shows a section along the line III-III from), the shaft has an increased wall thickness DWP, which is 1.4 mm in the present exemplary embodiment, and which in other design variants of the endoscopic probe according to the invention can be in the range of 1.3 to 1.5 mm, in particular in the range of 1.35 to 1.45 mm. Since the internal diameter of the shaft is the same along the entire length of the shaft, the external diameter DP of the shaftis correspondingly increased in the proximal portion. In the present example, the proximal portion extends over a length LP of 15 mm, although in other design variants it can also assume other values in the range of between 10 and 20 mm, in particular in the range of 13 to 17 mm. The stability of the shaft is increased by the strengthening in the proximal portion. It is thus possible to obtain a shaft which has a high degree of stability while at the same time having a small diameter in the distal portion and a large aperture.

Said diameters and wall thicknesses of the shaftare chosen such that they on the one hand allow the shaft to be inserted into narrow operating channels, while the shaft on the other hand still has sufficient stability to ensure that it is not damaged during handling. Moreover, the internal diameter of the shaft is large enough to, on the one hand, allow passage of an optical fibre, with which light from a light sourcearranged in the handlecan be conveyed to the distal endof the shaft, and, on the other hand, light reflected from the object observed by means of the endoscopic probe can be conveyed to a digital image sensor, for example a CCD sensor or a CMOS sensor, via an image-conveying optics system, which in the present case is configured as a coherent fibre bundle. Alternatively, there is also the possibility for the optics system to be configured in the form of lens combinations. In particular, the dimensions of the shaft allow it to receive an image-conveying optics system which permits the capture of HD videos by means of the digital image sensor. It is likewise possible to arrange the digital image sensoron or in the distal tip of the shaft.

To permit ergonomic handling of the endoscopic probe by a person using the probe, the grip portionof the handlehas a special cross section. This cross section is depicted in, which shows a section along the line IV-IV in. The cross section lies in a plane which extends perpendicularly with respect to the common plane of the shaft axis AS, the grip portion axis AG and the rear end axis AK. The cross section shown inhas a cross-sectional upper sideand a cross-sectional underside. In the grip portion, the cross-sectional upper sideforms the side of the grip portion on which lies the point of intersectionbetween the imaginary continuations of the shaft axis AS and of the rear end axis AK.

In the endoscopic probe according to the invention, the cross-sectional upper sidehas a convex central portionand, adjoining the latter, two portionsa,b which, in the present exemplary embodiment, are slightly convex. The convexities can vary along the grip portion axis AG. The tangents to the slightly convex portionsa,b form cut-outs from the limbs of an imaginary isosceles triangle whose apex lies centrally above the cross-sectional upper side. The angle δ at the apex is in the range of between 45 and 75 degrees and, in the present exemplary embodiment, measures 60 degrees, at least in a region of the grip portion. The surfaces of the grip portionthat are formed by the slightly convex portionsa,b of the cross-sectional upper side represent gripping surfaces at which the grip portion can be gripped with the thumb and with the tip of the index finger.

In the present exemplary embodiment, the cross-sectional undersidehas a central regionwith a central convexity, adjoined on both sides by portionsa,b which have a lesser convexity compared to the central convexity, i.e. a convexity with a greater radius of curvature. In the present exemplary embodiment, the radius of curvature is very great, such that the regionsa,b have no convexity at all. The regionsa,b extend symmetrically with respect to the axis of symmetry of the imaginary isosceles triangle of the cross-sectional upper side. At the connections of the straight portionsa,b of the cross-sectional underside to the straight portionsa,b of the cross-sectional upper side, it is in this way possible to obtain relatively sharp edgesa,b which can form a tactile marking and thereby contribute to safety in the handling of the endoscopic probe.

In the present exemplary embodiment, a bearing surface for the middle finger can be provided on the side of the grip portionformed by the cross-sectional underside, on which bearing surface the middle finger can rest. This bearing surface can be a region of the grip portionin which the central region of the cross-sectional undersidehas a flatter convexity, as is indicated by the broken linein.

The use of an endoscopic probe according to the invention together with a surgical microscopeis shown schematically in. In the example shown in, images from the bottomof an operating channelare captured with the aid of the shaftof the endoscopic probe. At the same time, during the handling of the endoscopic probe, the operating channelis viewed with the surgical microscopein order to monitor the movement of the shaftin the operating channel. It is important here that the endoscopic probe does not collide with the surgical microscopeduring a movement inside the operating channel, for example during a rotation about the shaft axis AS, during insertion into the operating channelor during withdrawal from the operating channel. Such a collision may be obtained by the described angled geometry of the shaft, the grip portionand the rear end. The rear end, arranged at an angle to the grip portion, allows the cable, emerging from the rear endin the present exemplary embodiment, to be expediently passed across the back of the hand.

To ensure that the handle, and in particular the front end, causes the least possible concealment of the viewing region observed with the surgical microscope, the front end, in a direction perpendicular to the shaft axis AS, has a protrusion O that is dimensioned such that the angle θ (cf.) between an imaginary line emerging from the distal endof the shaft, extending in the plane of the shaft axis AS, the rear end axis AK and the grip portion axis AG and tangent to the front endof the handle is not more than 8 degrees, preferably not more than 5 degrees. For this purpose, the protrusion O in the present exemplary embodiment can correspond at most to one tenth, in particular at most one fifteenth, and preferably at most one twentieth of the shaft length LS. In the present exemplary embodiment, the protrusion measures 5 mm at a shaft length of 120 mm, which corresponds to a twenty-fourth of the shaft length. The angle θ is 3 degrees. As is indicated in, it is thus possible to ensure that the opening coneof the observation beam path leading to the main objectiveis shaded only very slightly, if indeed at all, by the endoscopic probe.

It is also possible to choose the direction of the shaft axis AS such that the distal end, in relation to the point where the proximal endjoins the front endof the handle, is offset in the radial direction by the protrusion O, such that the front endobstructs the view of the distal end of the shafteven less.

In the present exemplary embodiment, the shaftand the handle, including the connection between the shaftand the handle, are impervious to liquid and gas. Moreover, the shaftand the handleare made of a material that can be sterilized in an autoclave. By virtue of the fact that the endoscopic probe is impervious to liquid and gas, the components arranged in the interior of the handle and of the shaft are protected during treatment in the autoclave, such that they are not damaged by the treatment. It is thus possible to work without drapes.

In the described embodiment the angle α has been 130 degrees, the angle β has been 130 degrees, and the angle γ has been 80 degrees. In another embodiment the angle α is 120 degrees, the angle β is 120 degrees, and the angle γ is 60 degrees.

The present invention has been described in detail on the basis of an exemplary embodiment for explanatory purposes. However, a person skilled in the art will appreciate that it is possible to depart from this exemplary embodiment. For example, the shaft, which is straight in the exemplary embodiment, may also be slightly curved, in which case the angles to the other axes are then determined using the orientation of the shaft axis in its portion directly adjoining the shaft portion of the handle. Further departures from the exemplary embodiment are possible, as has already been stated at various places in the description of the exemplary embodiment. Moreover, the endoscopic probe can be configured without cables, in which case data can then be transmitted, for example, via WLAN, Bluetooth or infrared transmission. In this case, for example, the rear end accommodates an antenna() for wireless transmission, and/or an accumulator() that supplies the energy required for the transmission. It is then possible to do without a sterilizable cable. The invention is therefore not intended to be limited to the exemplary embodiment with cable, but only to an endoscopic probe as claimed in the attached claims.