ENDOSCOPE

Abstract

An endoscope for inspection of the gastrointestinal tract of a mammal, in particular of the small intestine of a human, includes an elongated, flexible tubular structure and a flexible, elongated element placed inside the tubular structure such that a distal portion of the elongated element protrudes from a distal end of the tubular structure and is connected to an endoscopic tip, wherein the elongated element is engaged with the tubular structure in such way that a rotation of the tubular structure around the elongated element in a first rotation direction will increase a gap between the endoscopic tip and the distal end, while a rotation of the tubular structure around the elongated element in a second rotation direction, opposite to the first rotation direction, will decrease the gap between the endoscopic tip and the distal end.

Claims

1. Endoscope for inspection of the gastrointestinal tract of a mammal, in particular of the small intestine of a human, comprising an elongated, flexible tubular structure and a flexible, elongated element placed inside the tubular structure such that a distal portion of the elongated element protrudes from a distal end of the tubular structure and is connected to an endoscopic tip, wherein the elongated element is engaged with the tubular structure in such way that a rotation of the tubular structure around the elongated element in a first rotation direction will increase a gap between the endoscopic tip and the distal end, while a rotation of the tubular structure around the elongated element in a second rotation direction opposite to the first rotation direction, will decrease the gap between the endoscopic tip and the distal end.

2. Endoscope according to claim 1, wherein said engagement between the elongated element and the tubular structure is by way of an engaging element engaging with a thread structure.

3. Endoscope according to claim 1, wherein said thread structure is a thread formed on an outside surface of said elongated element.

4. Endoscope according to claim 1, wherein said engagement between the elongated element and the tubular structure is effected at two or more positions along a length of the elongated element and/or the tubular structure.

5. Endoscope according to claim 1, wherein said elongated element and said tubular structure are arranged coaxially.

6. Endoscope according to claim 1, wherein said tubular structure comprises a spiraling surface structure.

7. Endoscope according to claim 1, wherein in a completely retracted position, in which said endoscopic tip is abutting said distal end of said tubular structure, a seal is formed between said endoscopic tip and said distal end for distally sealing an inner lumen of said tubular member.

8. Endoscope according to claim 1, wherein said endoscopic tip has substantially a same diameter as said distal end of said tubular structure.

9. Endoscope according to claim 1, wherein said endoscopic tip comprises a camera.

10. Endoscope according to claim 1, comprising one or multiple actuation and/or sensory module(s).

11. Endoscope according to claim 10, wherein said actuation and/or sensory module(s) is/are from the group of a biopsy sampling module, an impedance measurement module, a fluid or drug delivery module, a camera module, a handling module for handling or holding the endoscope, or any combination thereof.

12. Endoscope according to claim 10, comprising multiple actuation and/or sensory modules arranged at regular intervals along a length of said tubular structure.

13. Endoscope according to claim 10, wherein one, multiple or all of said modules are configured to be activated by a change of pressure of an inner lumen of said tubular structure.

14. Endoscope according to claim 1, wherein a proximal end of said elongated element is extending proximally beyond a proximal end of said tubular structure.

15. Endoscope according to claim 1, wherein a proximal end of said elongated element is positioned inside said tubular structure.

Description

[0032] Some examples of embodiments of the present invention will be explained in more detail in the following description with reference to the accompanying schematic drawings, wherein:

[0033] FIG. 1 shows a cut-away view of an endoscope according to a first embodiment;

[0034] FIG. 2 shows a cross-sectional view of an endoscope according to a second embodiment;

[0035] FIG. 3 shows a cross-sectional view of an endoscope according to a third embodiment;

[0036] FIG. 4 shows a cross-sectional view of an endoscope according to a fourth embodiment;

[0037] FIGS. 5a-5d show four different embodiments of actuation and/or sensory modules that can be arranged along the endoscope;

[0038] FIG. 6 shows a cross-sectional view of a biopsy sampling module according to one preferred embodiment; and

[0039] FIG. 7 shows an exploded-view drawing of the biopsy sampling module shown in FIG. 6.

[0040] FIG. 1 shows a distal part of an endoscope according to a first embodiment. The endoscope comprises a tubular structure 10, which is made of a metallic spiral reinforcement 12 and a flexible membrane closing the gaps between adjacent sections of the spiral reinforcement 12. The tubular structure 10 surrounds an inner lumen 11, which may be pressurized or depressurized for various functions. The tubular structure 10 ends in a distal end 14, which has a distal opening 13.

[0041] An elongated element 22 runs through the inner lumen 11 of the tubular structure 10, and through the distal opening 13, ending in an endoscopic tip 3. The elongated element 22 is rotationally engaged with the tubular structure 10 such that a relative rotation of the elongated element 22 and the tubular structure 10 will result in a corresponding linear movement between the elongated element 22 and the tubular structure 10 along a joint longitudinal axis.

[0042] For providing the rotational engagement, the elongated element 22 is surrounded by a thread structure 2, in particular a spiraling wire, attached to a tube. The tube itself may also be made of a spiraling wire, which is more densely packed than that of the thread structure 2. There is an engaging element in the form of a bearing ball 18 placed inside the distal end 14 of the tubular structure 10. The bearing ball 18 engages with the thread structure 2 to translate rotational movement of the tubular structure around the longitudinal axis into linear or translational movement of the elongated element along the longitudinal axis. The bearing ball 18 is held inside the distal end 14 by a sleeve 16.

[0043] The movement of the elongated element 22 with respect to the tubular structure 10 along the longitudinal axis causes the endoscopic tip 3 to move in the same fashion with respect to the tubular structure 10. When the elongated element 22 is retracted as far as possible into the tubular structure 10, the endoscopic tip 3 is in a retracted position (not shown in the figures). In this position, it will cover the opening 13, and, if so configured, also seal the inner lumen 11 at the opening 13, allowing the inner lumen 11 to be pressurized or depressurized. Alternatively, the distal opening 13 may be a sliding seal, which ensures that the inner lumen 11 is sealed against the outside even when the endoscopic tip 3 is not in the retracted position.

[0044] When the tubular structure 10 is rotated in one direction (e.g. counterclockwise), the rotational engagement causes the endoscopic tip 3 to move forward, away from the distal end 14. In FIG. 1, the endoscopic tip 3 is shown in an extended position, in which a gap 34 is formed between the endoscopic tip 3 and the distal end 14 of the tubular structure 10. If, at this point, the tubular structure 10 is rotated in the other direction (e.g. clockwise), the rotational engagement causes the tubular structure 10 to move forward along the spiraling wire of the thread structure 2 towards the endoscopic tip 3, thus reducing the gap 34.

[0045] As in all embodiments shown in the FIGS. 1-4, the elongated element 22 passes freely through the inner lumen 11 of the tubular structure 10, and is only attached to the tubular structure 10 by means of the distal rotational engagement mechanism between the bearing ball 18 (or other suitable means of engagement) and the thread structure 2. Thus, the elongated element 22 is not limited in its range of linear motion and the gap 34 between the endoscopic tip 3 and the distal end 14 is exposed. In particular, the section of the elongated element 22 that is inside the gap 34 is exposed to the environment inside the small intestine.

[0046] The endoscopic tip 3 comprises a camera 32, which is configured to take images or video images of the inside of the intestine. The images may be sent in digital form via wireless connection to an outside device, such as a computer. Alternatively, the camera may be connected via wires, which may run through a central lumen 23 of the elongated element 22. The three embodiments of the endoscope have such wires running through the central lumen 23, as can be seen in FIG. 2-4.

[0047] The elongated element 22 of the endoscope shown in FIG. 1 extends beyond the proximal end (not shown in FIG. 1) of the tubular structure 10. As can be seen in FIG. 1 on the right side, the part of the elongated element 22 that extends in such a manner outside of the tubular structure 10, is not necessarily covered by the thread structure 2 anymore. It is only necessary for the thread structure 2 to be disposed on a relatively short length of the elongated element's 22 distal end because the “stroke” of the device may be only 20-30 cm.

[0048] As can be seen in FIG. 1, the spiral reinforcement 12 may cause the outer surface of the tubular structure 10 to have a spiraling or helical structure. This helical structure can engage with the intestinal wall and aid in the forward movement of the endoscope during rotation of the tubular structure 10. While the endoscope according to the third embodiment shown in FIG. 3 also shows this helical structure due to the spiral reinforcement 12 impinging through the outer surface of the tubular structure 10, the embodiments shown in FIGS. 2 and 4 show a smooth surface of the tubular structure 10. In these embodiments, the spiral reinforcement 12 is buried deeper in the flexible membrane material.

[0049] An endoscope according to a second embodiment is shown in FIG. 2. The endoscope comprises a sliding seal 61 at its proximal end 6, which seals the inner lumen 11 of the tubular structure 10, even when the elongated element 22, which proximally extends beyond the proximal end 6, rotates and/or moves along the longitudinal axis. The proximal end 6 is made of an end element with an inlet 62 for introducing gaseous or liquid substances into the inner lumen 11. The inlet 62 may be utilized to change the pressure inside the inner lumen 11, e.g. to pressurize or to depressurize it, in particular for activating any modules that are actuated by a change of pressure.

[0050] In this embodiment, the thread structure 2 is only provided on a distal section of the elongated element 22, and thus ends within the inner lumen 11 of the tubular structure 10. As the thread structure 2 only serves for providing the rotational engagement between the tubular structure 10 and the elongated element 22, it is not necessary that it extends much beyond the engagement element 18 at the most possible or practical extension position of the endoscopic tip 3. This is also the case for the endoscope according to the third embodiment shown in FIG. 3. In addition, as explained earlier, the tubular structure 10 of the endoscope in FIG. 3 has a spiraling surface due to the spiral reinforcement 12, which is not completely buried in the flexible membrane material surrounding it. This is the only difference visible in the FIGS. 2 and 3 between the endoscopes shown there.

[0051] FIG. 4 shows an endoscope according to a fourth embodiment. The endoscope comprises two modules 5, which are arranged at a distance along the tubular structure 10. These may be any kind of actuation and/or sensory modules. As the embodiment shown in FIG. 4 is only an exemplary one, there may of course me more than two such modules 5 arranged along the endoscope, which are not shown in FIG. 4 because FIG. 4 only shows three sections of the endoscope.

[0052] The endoscopic tip 3 of each of the endoscopes shown in FIGS. 1-4 includes an endoscopic camera 32 for imaging the intestine while the endoscope advances into it. While this might also be the case in an alternative embodiment to that of FIG. 1, FIGS. 2-4 explicitly show wires 25 connected to the camera 32 running through the central lumen 23 of the elongated element 22.

[0053] Each of the endoscopes shown in FIGS. 1-4 include a pair of distal electrodes 19, one of which is attached to the proximal end of the endoscopic tip 3 and the other to the distal end 14 of the tubular structure 10. By depressurizing the inside lumen 11 of the tubular structure 10, the volume inside the gap 34 between the endoscopic tip 3 and the distal end 14 may be depressurized as well due to the link formed by the distal opening 13, thus sucking in part of the intestinal wall. The endoscopic tip 3 can then be retracted towards the distal end 14 in order to sandwich a part of the intestinal wall between the pair of distal electrodes 19 for impedance measurement.

[0054] The endoscopic tips 3 shown in the embodiments in FIGS. 2-4 each include a steering magnet 36, which can be utilized in order to steer the endoscopic tips 3 and thus the endoscope with the help of a magnetic field produced outside of the patient's body and penetrating the intestine.

[0055] FIGS. 5a-5d show schematic cross-section drawings of different actuation modules and sensory modules incorporated in a tubular structure 10 of an endoscope. The module shown in FIG. 5a, a fluid or drug distribution module 52, may be regarded as an actuation module. Upon activation, the fluid or drug distribution module 52 releases a substance into the intestine. The amount of the released substance may be fixed before the start of the endoscopic procedure, e.g. by filling the module 52 with a desired portion of the substance, all of which will be released simultaneously upon activation. Alternatively, the module 52 might be filled with a certain amount of the substance, a dosage of which is released upon activation, where the dosage may be controlled upon activation.

[0056] Alternatively, the fluid or drug to be released may be pumped through the inner lumen 11 and flow out of the distribution module 52 or out of some or all of the distribution modules 52, in case more than one such module 52 is provided.

[0057] FIGS. 5b and 5c show sensory modules. In FIG. 5b, a camera module 53 is shown, which the endoscope may be equipped with, instead of or in addition to the endoscopic camera placed on the endoscopic tip. The camera module 53 is comprised of an image sensor 531 and a clear casing 532 protecting the image sensor 531. The camera module 53 may be equipped with more than one image sensor 531 for taking still or video images of different locations of the intestine and/or at different angles. Alternatively or in addition, the image sensor 531 or sensors (not shown) may be configured to be movable with respect to the camera module 53 or with respect to the tubular structure 10.

[0058] The sensory module shown in FIG. 5c is an impedance measurement module 51. For measuring in particular a transepithelial impedance in the intestine, the module 51 comprises two or more module electrodes 511, which are electrically insulated against each other. An impedance measuring circuit may be located in the impedance measurement module 51 or in a different position on the endoscope. Alternatively, wires may lead from the module electrodes 511 to the proximal end of the endoscope and be connected to an impedance measurement device located outside of the endoscope.

[0059] FIG. 5d shows a handling module 54, which is configured to hold or engage with a tool for handling the endoscope. The tool may preferably be configured for helping the physician to exert more torque on the tubular structure 10 and/or rotate it more quickly. As the movement into the small intestine is effected mainly by rotation of the tubular structure 10 in alternating rotation directions, and rotating the tubular structure 10 becomes increasingly cumbersome due to friction, the use of such a tool may greatly facilitate the work of the physician. The handling module 54 in the embodiment of FIG. 5d is equipped with two wrench flats 541 on opposite sides of the tubular structure 10, which allow a tool such as a wrench to be attached to it or engaged with it.

[0060] A preferred embodiment of a biopsy sampling module 4 is shown in a cross-sectional view in FIG. 6 and in an exploded view in FIG. 7. The biopsy sampling module 4 comprises the following parts arranged on a central shaft 42: a spring holder 41 holding a torsion spring 43, a sampling wheel 44 configured as a rotating blade 44, a piston 45, a piston spring 46, a casing 47, and an endcap 48. The central shaft 42 is configured to be fixed to the tubular structure 10. It has a lumen through which the elongated element 22 passes, and which is in fluid contact with the inner lumen 11 of the tubular structure 10. The torsion spring 43 is engaged with the sampling wheel 44, which in turn is free to rotate around the central shaft 42. The sampling wheel 44 has a cutout which may itself serve as a biopsy tool, or into which a disposable sample holder may be inserted and later removed.

[0061] The disposable sample holder (not shown in the figures) comprises a receptacle where the sample is stored, and a blade or brush with which the biopsy is obtained. The casing 47 surrounds the sampling wheel 44, guarding the disposable sample holder when not in use and protecting the sample holder from cross-contamination both before and after the sampling occurs. The casing 47 further has a cutout to allow the sampling blade or brush to contact the tissue when the module 4 is triggered. The piston 45 is fitted around the central shaft 42 just behind the sampling wheel 44 and is free to move linearly along the shaft axis. The piston spring 46 pushes the piston 45 up against the sampling wheel 44, locking the sampling wheel 44 in place. The piston 45 has a pin (not shown) to prevent the rotation of the sampling wheel 44.

[0062] When the lumen of the sampling module 4 is pressurized, holes in the central shaft 42 allow the air to push the piston 45 back against the piston spring 46, releasing the sampling wheel 44 and causing the biopsy to be taken. At the end of its stroke, the sample holder has rotated by approximately 180 degrees and is now protected from contamination by the other side of the casing 47. When the pressure is released, the piston 45 returns to its original position, fixing the sampling wheel 44 in its final position. Pressurizing and depressurizing the

[0063] sampling module 4 in order to displace the piston 45 is performed by pressurizing and depressurizing the inside lumen 11 of the tubular structure 10 by way of the inlet 62. The endcap 48 is fixed to the central shaft 42 as well as to the tubular structure 10.

[0064] The endoscope is equipped with a number of sampling modules 4 periodically disposed along its length for the purpose of obtaining biopsies or scrapings of the epithelial tissue. These sampling modules 4 are pre-loaded and can be triggered simultaneously, ensuring that biopsies are taken at regular distance intervals along the intestine. The biopsy sampling modules 4 may for example be arranged at regular intervals of between 20 cm and 25 cm. In this case, there may be between 24 and 30 such modules provided along a 6 m length of the tubular structure 10.

REFERENCE NUMERALS

[0065] 10 tubular structure [0066] 11 inner lumen of tubular structure [0067] 12 spiral reinforcement [0068] 13 distal opening [0069] 14 distal end [0070] 16 bearing ball cover [sleeve] [0071] 18 bearing ball [0072] 19 distal electrodes [0073] 2 thread structure [0074] 22 elongated element [0075] 23 central lumen of elongated element [0076] 25 wires [0077] 3 endoscopic tip [0078] 32 camera [0079] 34 gap [0080] 36 steering magnet [0081] 4 biopsy sampling module [0082] 41 spring holder [0083] 42 shaft [0084] 43 torsion spring [0085] 44 rotating blade [0086] 45 piston [0087] 46 piston spring [0088] 47 casing [0089] 48 endcap [0090] 5 modules [0091] 51 impedance measurement module [0092] 511 module electrodes [0093] 52 fluid or drug delivery module [0094] 53 camera module [0095] 531 image sensor [0096] 532 clear case [0097] 54 handling module [0098] 6 proximal end [0099] 61 sliding seal [0100] 62 inlet