DE8904011U1 - Endoscope, especially arthroscope - Google Patents

Description

EP39.G2 Sheet 7

Description

The invention relates to an endoscope of the type specified in the preamble of claim &igr;.

Such endoscopes are used, particularly in the form of arthroscopes, for the examination and treatment of acute joint spaces, mostly the knee joint.

It is known that the viewing angle of the optical system is of great practical importance. Compared to a straight-ahead optic, a viewing direction inclined by, for example, 30° to the optical axis has significant advantages. The instrument's guide axis still remains in the field of view and the oblique viewing angle allows the field of view possible in a certain position to be significantly expanded by rotating the instrument. However, if the viewing direction is inclined even further to the optical axis, for example by 70', the displacement axis is only in the field of view when wide-angle optics are used. The disadvantage of rotating the entire instrument is the fact that connections, handles and image evaluation systems, in particular the connection piece for the lighting, which usually protrudes radially to the instrument's longitudinal axis, including the light guide cable leading to a light source, have to be rotated as well. Even with a two-part design of the endoscope, in which an observation assembly can be freely rotated relative to an illumination assembly, such difficulties arise if

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EP39.G2 Sheet 8

For example, a video camera is used for observation. In addition, the opening angle of the illumination cone must be very wide, since it is not possible to adjust the direction of illumination to the direction of observation unless the illumination assembly is also rotated. This again corresponds to the first case described above.

The invention is based on the object of improving the durability and at the same time the range of applications of an endoscope of the type mentioned at the beginning.

This task is carried out with the characteristic features of the 15

Claim 1 is resolved.

According to the invention, at least the end of the optics closest to the object is arranged so that it can be moved relative to the connection piece. The angle of rotation can be 360* or more.

According to an advantageous development of the invention, the shaft of the endoscope carrying the optics and light guide consists of two essentially cylindrical sections, whereby the separation point of the two sections is preferably provided between two optical elements and the rotation of the section closest to the object around the longitudinal axis of the shaft is permitted. If the separation point is arranged in front of the illumination nozzle as seen from the end closest to the object, the part of the illumination closest to the object can be rotated together with the part of the observation lens closest to the object, which is possible with a viewing direction inclined to the optical axis and an observation angle inclined in the same way.

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illumination direction is required so that the illuminated and the object space to be observed are almost identical in every rotation phase. For the same reason, the opening angle of the illumination cone must be at least the same size as the object-side opening angle of the observation beam path, in the interest of a light-resistant

Iron Roioiirht-nnn &EEgr;&udigr;&egr; nMoltfhorairhas and to avoid a-

However, the two angles should not deviate too much from one another to avoid unnecessary and tissue-stressing neighboring zone illumination. The separate rotatability of the section of the endoscope shaft closest to the object, according to the invention, allows a "panoramic view" while avoiding the annoying rotation of cable connections, handles and image evaluation or recording devices on the eyepiece side that occurs with conventional endoscopes.

According to another advantageous development of the invention, the separation point is provided behind the lighting socket when viewed from the end closest to the object. In this case, the section closest to the object consists of an optics-carrying frame and a light guide ring that concentrically surrounds the frame, whereby the frame can be rotated within the ring. The light guide ring has a fixed position relative to the eyepiece-side section of the endoscope shaft. Only the distal section of the optics-carrying frame can be rotated. This ensures that, for example, image evaluation or image recording devices that are attached to the eyepiece-side section of the optics-carrying frame also have a fixed spatial position. The rotatability of the section closest to the object of the optics-carrying frame enables the lens to be bent

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The viewing direction also provides a "panoramic view". A correspondingly wide-angle device is then required for illumination. With wide-angle illumination, the light exit surfaces of the light guides primarily form a truncated cone-like or concave end of the section closest to the object. This object-side shape is particularly advantageous for arthroscopic examinations, where a smooth transition from the light exit surface to the trocar is advantageous due to the associated reduced cartilage injuries.

15

25

In a special embodiment, the light guides are divided at their ends close to the object into an inner region with a circular light exit surface immediately adjacent to the optics mount and a peripheral region with a conical light exit surface. The division is preferably implemented by inserting a ring with an essentially triangular cross-section.

The separation point can be designed as a dovetail ring or as a collar ring. In both cases, the two sections can be well centered relative to one another while remaining fully rotatable. To prevent a threaded collar ring from accidentally turning off, it can be fixed in position by gluing or locking it in a shaft section. However, it is then no longer possible to interchange or optionally attach different shaft centering rings.

For convenient handling of the rotating part, a knurled ring is preferably used, which is attached to the connection piece for

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the end of the section closest to the object facing the illumination is mounted concentrically around its longitudinal axis.

The rotation can also be generated with the help of a battery-operated motor, whereby the motor is connected to the
observation-side section, in particular on or in a handle, and the motor shaft acts directly or via gear elements on the periphery of the section close to the object or the knurled ring and sets it in rotating motion.

Advantageous further developments of the invention are characterized in the subclaims or are presented in more detail below together with the description of the preferred embodiment of the invention using the figures. They show:

Figure 1 shows a longitudinal section through an arthroscope with a separation point for the optical fibers arranged in front of the illumination nozzle as seen from the end closest to the object and a separation point for the optics arranged behind the illumination nozzle,

Figure 2 an arthroscope with a separation point for the optical fibers and the optics arranged in front of the illumination nozzle when viewed from the end closest to the object and with the viewing and illumination direction inclined to the optical axis,

Figure 2a the illuminated and observed object field according to Figure 1,

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Figure 3 a dovetail design of an interface!,

Figure 4 an endoscope with a separation point for the optics located behind the illumination nozzle when viewed from the end closest to the object and a viewing direction inclined to the optical axis and a wide-angle illumination in the axial direction,

Figure 4a the illuminated and observed object field according to Figure 3,

Figure 5 shows a section through the object-near end of a wide-angle illumination,

Figure 6 is a perspective view of an endoscope according to Figure 3,

Figures 5a to 6e Individual parts of the endoscope according to Figure 6,
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Figure 7 shows a first variant of a motor-driven knurled ring adjustment,

Figure 8 shows a second variant of a motor-driven knurled ring adjustment.

Figure 1 shows a longitudinal section through an endoscope according to the invention in the form of an arthroscope for examining the interior of the knee joint 1. Such an arthroscope consists of a trocar sleeve 2, a suction 3 and/or irrigation channel connection 4 and an endoscopic

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scopic device 5, which can be pushed into the trocar sleeve 2. The endoscopic device 5 is made up of components for lighting and object observation. Optical fibers 6 are usually provided for lighting, which are arranged concentrically around an optical mount 7 and are connected to a light source via a lighting nozzle 8 protruding to the side and a light guide cable. The suction and/or rinsing channel runs between the optical fibers 6 and the optical mount 7. Bars (not shown in the figure) are provided for stabilizing and spacing the optical fibers 6 from the optical mount 7. The optical mount 7 contains an objective 9 and a number of image displacement lenses 10, which project the object 1 into the intermediate image plane of an eyepiece for visual observation or onto the endicon of a camera II for monitor observation or image recording. The optical axis 12 is also the longitudinal axis of the endoscope 5 and the trocar 2. The endoscope 5 consists of an optical part that can be rotated coaxially to a camera, an object-side lighting part 13 and an observation-side lighting part 14, whereby the optical part and the object-side lighting part 13 connected to the optical part via webs can be rotated axially relative to the observation-side lighting part 14 by means of a knurled ring 40. The separating parts 15 between the object-side lighting part 13 and the observation-side lighting part 14 are located in front of the lighting nozzle, as seen from the end closest to the object, but behind the connecting webs between the optical part and the object-side lighting part 13. In this way, the lighting

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The supply nozzle 8, the suction 3 and/or flushing channel connection 4, the camera 9 and a handle or a holder 16 maintain a constant spatial position when the optical part 13 is rotated and do not rotate.
5

Figure 2 shows an embodiment which corresponds in its basic structure and in terms of the objective to the embodiment shown in Figure 1. Here too, the object-side optics mount and the object-side lighting part (together forming 13') can be rotated together around an eyepiece-side part 14', with the separation point between the two parts being arranged in front of the lighting socket when viewed from the object-side end. The special design of the arthroscope is different. While in the variant shown in Figure 1 a suction/rinsing channel is arranged between the optics and the lighting, according to Figure 2 this runs inside the trocar sleeve 2. As a result, the optics mount 7 and the optical fibers 6 are immediately adjacent and connected to one another along the entire longitudinal extent of the endoscope shaft. Connecting bridges are therefore no longer required. The compact design of the endoscope means that the separation point 15 practically divides the optical fibers 6 and the optics mount 7, i.e. the entire endoscope, into an object-side section 13' and an observation-side section 14'. By axially rotating the object-side part 13' of the endoscope 5, a tissue-protecting observation of a large object field 17 (Figure 2a) can be achieved with the viewing direction angled to the optical axis 12, analogous to the embodiment according to Figure 1, since a lateral displacement of the arthroscope is avoided; in Figure 2, two 180°-angled sections are shown.

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The positions of the object-side endoscope part 13* rotated relative to one another are shown. The angle range 18 is aimed at observing the object field 19 (Figure 2a). When the object-side endoscope part 13' is rotated by 130°, the angle range 20 or the object field 21 (Figure 2a) is in the field of view. The size of the angle 18 or 20 corresponds to the opening angle of the endoscope lens 9. In order to achieve a bright and even illumination of the object field, the direction of illumination deviates by the same amount.

.10 amount utsd in the same spatial direction from the optical axis 22 as the direction of observation. For the same reason, the illuminated area is only slightly larger than the observable object field. In the rotational position for observing the object field 19, the angular range 22 or the field 23 superimposed on the object field 19 (Figure 2a) is illuminated, and when the position is rotated by 180*, the angular range 24 or the field 25 superimposed on the object field 21 (Figure 2a) is illuminated.

Figure 3 shows a special variant of a separation point 15 in the form of a dovetail joint 26. This type of connection of cylindrical parts is characterized by precise adjustability, simple construction and universal applicability. The part 27 of the dovetail joint 26 facing the object end can also serve as an actuating means for the rotary movement and is then expediently designed as a knurled ring.

A separation point designed in this way can be used both in the first variant shown in Figures 1 and 2 and in the second variant shown in Figures 4 and 6.

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of the invention. In contrast to the first variant, the interface 15';,, is located behind the lighting connector 8 when viewed from the object-side end. The second, essential difference to the

f 5 The variant shown in Figures 1 and 2 consists in that the part 13" near the object consists of a separate, essentially ring-shaped optical fiber illumination device 28 and a rotatable within this ring

£ optic-bearing frame 29, whereby the optic-bearing

f 10 frame 29 is part of the observation assembly of the endoscope. A rotation of the distal part 13" consequently causes an axial rotation of the optics-bearing frame 29 within the fixed optical fiber illumination device 28. With a viewing direction inclined to the optical axis 12,

A field 30 (Figure 4a) is illuminated, which should be considerably larger than the field of view 31 or 32 (Figure 4a). In a certain rotation position, the angle

\ area 33 and thus the object field 31 (Figure 4a)

; and in a position rotated by 180* to this

Position of the angle range 34 and thus the object field 32. The illuminated solid angle 3t> or the illuminated field 30 is constant. An advantageous arrangement of the light

&iacgr; conductive fibers at their object-side light exit&end for

\ Such a wide-angle illumination is shown in Figure 5

shown.

The second variant of the invention is particularly advantageous when no protective trocar sleeve 2 (Figures 1 and 2) is provided or when a severing of the light guides due to an uneven fiber cross-section deviating from a circular ring area

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is not sensible. Both variants are characterized by a more comfortable, more precise and less damaging to the tissue than conventional systems. Changing the viewing direction by turning no longer leads to the cumbersome turning of the optical fiber connection, the handle and additional devices on the eyepiece side. In addition, the separation point - provided it is designed as a real separation point - allows the exchange or optional attachment of various object-side and/or observation-side endoscope assemblies.

The wide-angle illumination shown in a longitudinal section in Figure 5 is characterized by two separate ring-shaped light exit surfaces. An inner, ring-shaped light exit surface 36 immediately adjacent to the optics mount 29 is separated from a conical light exit surface 38 by a ring 37 with an essentially triangular cross-section. The two light exit areas and the ring acting as a spacer form a smooth surface. This smooth surface is continued if a trocar sleeve 2 is present. Tissue damage when inserting the endoscope is thus largely avoided. The angle ranges of the light exit of the two light exit areas overlap as shown in dashed lines in Figure 4. It is also clear that very wide-angle illumination is achieved in this way.

Figure 6 shows a perspective view of an endoscope according to the principle of the second variant of the invention illustrated in Figure 4. The individual parts and

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the assembly sequence is shown in Figures 6a to 6e. The endoscope essentially consists of an optical fiber illumination device 28 with illumination nozzle 8 (Figure 6a), a rod-shaped optics assembly 39 with a knurled ring 40 (Figure 6b) for rotating the optics assembly 39 about its optical axis 12, a connection 41 for a suction and/or rinsing channel extending between the optics assembly and the illumination device, a handle 16 (Figure 6c) and an adapter 42 (Figure 6d) for adaptation to a camera 11 (Figure 6e). The illumination nozzle 8 is advantageously integrated into the handle 16.

When the knurled ring 40 is actuated, the optical assembly 39 is rotated around its optical axis 12 within the suction/rinsing channel and the lighting assembly. The knurled ring 40 is located in the immediate vicinity of the handle 16 and is therefore easily accessible. The current viewing direction can be identified by means of a marking 43 on the knurled ring 40. The radial position of the knurled ring marking 43 advantageously corresponds to the radial viewing direction. It is also possible to reflect a marking to indicate the position of the knurled ring 40 and thus the viewing direction into the optical image.

The variants of motorized adjustment devices for the knurled ring 40 shown in Figures 7 and 8 consist of a motor 44 installed in the handle 16 of the endoscope or arthroscope, a battery 45 also arranged in the handle 16, a slide switch 46 and various gear elements that transfer the energy of the motor 44 to

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the knurled ring 40 and thus cause a rotary movement of the optical assembly 39 relative to the lighting assembly 28.

The gear elements in the first variant shown in Figure 7 are designed as worm gear/pinion combinations. The motor shaft 47 carries a worm gear 48, which is in engagement with a pinion 49. The axis of rotation 50 of the pinion 49 is arranged in a radial plane of the knurled ring 40 and perpendicular to the axis of rotation 51 of the worm gear 48. The pinion 49 is rigidly connected via its axis to two worm gears 52 and 52'. These worm gears 52 and 52' engage in two pinions 53 and 53', the axes of rotation 54 and 54' of which are directed perpendicular to the radial plane of the knurled ring 40 and perpendicular and symmetrical to the axis of rotation 51 of the worm gear 48. These pinions 53 and 53· are simultaneously the drive elements for the knurled ring 40. The type of knurling practically corresponds to a rack-like shape.

A slide switch 46 is used to switch the motor 44 on and off. This switch is located on the handle 16 of the endoscope or arthroscope in an ergonomically favorable position. When the slide switch 46 is operated, not only is the circuit interrupted or closed, but the force connection between the drive elements and the knurled ring 40 is interrupted or established at the same time. This dual function is advantageous because it allows manual rotation of the knurled ring 40. To implement this dual function, the slide switch 46 is equipped with

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a movable base plate 55 on which the gear elements, the motor 44 as well as an elastic line connection 56 and a connecting line 57 with a switchable contact 58 between the motor 44 and the battery 45 are mounted. When the slide switch 46 is operated in the direction of the knurled ring 40, the base plate 55 is also moved, whereby the contact 58 is connected to a pole of the battery 45 and at the same time the drive elements are pressed against the periphery of the knurled ring 40. The contact 56 between the motor 44, which can be moved on the base plate 55, and the battery 45, which is firmly inserted in the housing of the handle 16, remains constant regardless of the switching state due to the elastic properties of the contact 56.

Another preferred embodiment, particularly with regard to the gear elements, is shown in Figure 8. The motor shaft 47 carries a worm gear 48, similar to the embodiment according to Figure 7. A pinion 59 engages in this, the axis of rotation 60 of which is both perpendicular to the axis of rotation 51 of the worm gear 48 and perpendicular to a radial knurling ring plane. On the axis* of the worm gear 59 sits a friction wheel 61, which drives a belt 62, which in turn drives two rollers 63 and 63'. The axes of rotation 64 and 64· of the two rollers 63 and 63', like those of the pinion 59 and thus of the friction wheel 61, are perpendicular to the axis of rotation 51 of the worm gear 48 and perpendicular to the knurling ring plane. The rollers 63 and 63* are also arranged mirror-symmetrically to the plane of the rotation axes 51 and 60 in such a way that they touch the periphery of the knurled ring 40. With corresponding surface properties

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properties of the periphery of the knurled ring 40 and the '-rollers 63 and 63', these move the knurled ring 40 through

Frictional engagement in rotating motion. f,

The invention is not limited in its execution &idigr;

to the preferred embodiment given above |

game. Rather, a number of variants are conceivable, |

who also use the solution presented in fundamentally different versions. *****

Claims (17)

EFPNER QnbH 28 March D-IOOC Berlin EP39.G2 Endoscope, in particular arthroscope claims 1. Endoscope, in particular arthroscope, consisting of an essentially cylindrical shaft carrying optics and light guides, the optical axis coinciding with the longitudinal axis of the shaft and the light guides preferably being arranged concentrically around the optics EF39.G2 Sheet 2 and a connecting piece directed radially to the longitudinal axis of the shaft, via which the light guides are connected to a light guide cable leading to a light source, the viewing direction from the top end being directed towards the central axis. characterized ,. that at least the end of the optics closest to the object is arranged so as to be rotatable with respect to the connectors. 2. Endoscope according to claim 1, characterized in that the angle of rotation is substantially 360° or more. 3. Endoscope according to one of the preceding claims, characterized in that at least one region close to the object, but preferably the entire length of the light guide surrounding the optics, is arranged spatially fixed in relation to the connection piece. 4. Endoscope according to one of the preceding claims, characterized in that the shaft carrying the optics is designed to be coaxially rotatable within a hollow tube accommodating the light guides. EP39.G2 Sheet 3 5. Endoscope according to one of the preceding claims, characterized in that the &psgr;. -Shaft made of two essentially cylindrical sections S ten (13 or I3 ^S or 13" and 14 or 14·) with a rf 5 separation point (15 or 15'), that the separation point ;■■ (15 or 15') is preferably arranged between two optical elements and that means for rotating the object - near section (13 or 13' b2w. 13") about the longitudinal axis % (12) of the shaft. &iacgr;&ogr; 6. Endoscope according to one of the preceding claims, ■'.'. characterized in that the j separation point (15) is arranged in front of the '■ 15 connection (8) as seen from the end closest to the object. 7. Endoscope according to one of claims 1 to 5, characterized in that the separation point (15') is arranged behind the connection piece (8) as seen from the end closest to the object. 8. Endoscope according to one of the preceding claims, characterized in that the illumination angle and the viewing angle correspond in magnitude and spatial direction and d.i3 the opening angle of the illumination cone (22 or 24]i is equal to or greater than the object-side opening angle (16 or 20) of the observation beam path. EF39.G2 Sheet 4 9. Endoscope according to one of the preceding claims, characterized in that a dovetail ring (26) is provided at the separation point (15 or 15'). 10. Endoscope according to one of claims 1 to 4. d a characterized by that a collar ring is provided at the separation point. 11. Endoscope according to claim 10, characterized in that means for securing the coupling ring, in particular adhesive means or locking means, are provided. 12. Endoscope according to one of the preceding claims, characterized in that a knurled ring (40) is provided at the end of the section near the object (13 or 13' or 13") concentrically around its longitudinal axis (12) facing the connection piece (8). 13. Endoscope according to one of the preceding claims, characterized in that a battery-operated motor (44) is provided which is connected to the section (14 or 14·) remote from the object and whose shaft (47) acts directly or via gear elements on the periphery of the section (13 or 13' or 13") close to the object and sets it in rotating motion. /5 EF39.G2 Sheet 5 14. Endoscope according to one of the preceding claims, characterized in that the light guides are designed as glass fiber guides. 15. Endoscope according to one of the preceding claims, Light guides are designed such that the opening angle (35) of the illumination cone is at least 110*. 16. Endoscope according to one of the preceding claims, characterized in that the object-side light exit surface of the light guide has a substantially conical or concave shape. 17. Endoscope according to one of the preceding claims, characterized in that the light guides at their ends near the object form an inner region immediately adjacent to the optics mount (29) with a circular light exit surface (36) and a peripheral outer region with a conical light exit surface (38), a ring (37) with a substantially triangular cross-section being provided for dividing the two regions.