Patent Application
20240206712
The present application relates to insertion instruments, in particular surgical insertion instruments, for insertion into a cavity, in particular in a human subject, as well as to systems comprising such instruments.
So called “growing robots” have been known for various fields of applications. Such a robot is known from US 2019/0217908 A1 which discloses an everted tubular sheet whose inner portion is wound up on a reel. By unwinding the tubular sheet from the reel and blowing a gas into a chamber enclosed by the sheet, the length of an outer portion of the sheet can be increased. However, when the sheet has been introduced into a cavity, the pressure inside the chamber usually prevents the insertion of any other device through the robot and into the cavity. Instead, in order to avoid piercing the sheet, the growing robot must be fully deployed or depressurized to allow the insertion of another device through a passage formed in the growing robot. Moreover, the instrument does not allow the removal of gases or liquids from the cavity.
US 2003/0168068 A1 discloses an instrument which can be used for medical purposes. The instrument is based on an everted tubular sheet. In one embodiment, an inflatable tubular sheet is arranged in such a way that an endoscope can be entered through a passage formed inside an inner portion of the sheet. However, since the inner portion is only loosely wrapped up in an initial state, the extension cannot be precisely controlled. Moreover, the process cannot be reversed so that the instrument cannot be easily retracted from the cavity.
Moreover, U.S. Pat. No. 5,236,423 discloses a tubular sheet whose inner portion is gathered in an initial state. This sheet has the same disadvantages, i. e. the extension cannot be precisely controlled, and the process cannot be reversed so that the instrument cannot be easily retracted from the cavity.
It is an object of the present application to provide an instrument in which at least some of the disadvantages mentioned above are overcome. In particular, it should allow a controlled release of the tubular sheet and the insertion of a device such as a surgical, therapeutic or diagnostic instrument or a sensor and simplify the retraction of the instrument.
In a first aspect of the invention, this is achieved by an insertion instrument, in particular a surgical insertion instrument, for insertion into a cavity, in particular a cavity of a human subject. The instrument comprises
As already mentioned, the insertion instrument may be a surgical insertion instrument that can be inserted into a cavity of a human subject. For example, it may be used to explore and perform procedures on the upper gastrointestinal tract, in particular esophagus, stomach, and/or small intestine, the lower gastrointestinal tract, in particular colon and/or rectum, the biliopancreatic tract, in particular common bile duct, intrahepatic bile ducts, cystic duct, and/or Wirsung canal, the urinary tract, in particular calyces of the kidney, ureter, bladder, and/or urethra, the respiratory tract, in particular trachea, bronchi, and/or bronchioles, the uterine cavity, the Fallopian tubes, the nasal cavities, the maxillary sinuses, the frontal sinus, the Eustachian tubes, the tear ducts, the brain ventricles, the central canal of the spina medulla, the mesencephalon aqueduct and the vessels.
However, the invention also encompasses insertion instruments which are adapted and can be used for non-medical purposes, such as for insertion into tubular structures of any kind, e. g. industrial tubes whose interiors have to be inspected, for example with the aid of a camera that can be introduced through the passage of the insertion instrument.
The distal tip is arranged in an area where the tubular sheet is everted. As will become clear from the exemplary embodiments, the inner portion and the outer portion hence dynamically change during the process of inserting the instrument. Moreover, the distal tip is not fixed but changes its location during use of the instrument. Hereinafter, the outer tubular portion and the inner tubular portion will sometimes together be referred to as the extension of the instrument. As will also become clear from the exemplary embodiments, the tubular sheet may be bent actively or passively during the process. In a bent state, the extension direction is to be understood as a local direction which changes along the extension.
A chamber may be formed which is at least partially enclosed by the inner portion of the sheet and the outer portion of the sheet. A fluid, which may be a gas or a liquid, can be introduced into the chamber in order to extend the device. When the sheet is at least essentially fluid-tight, controlling a fluid pressure inside the chamber can press the outer portion of the sheet against an interior wall of a cavity into which the instrument is inserted. Additionally, the length of the extension can be controlled at least in part by the fluid pressure and the amount of fluid inside the chamber.
As will be further explained, an interior device may be inserted through the passage defined inside the inner tubular portion, in particular a surgical, therapeutic or diagnostic instrument, a sensor, a robot (in particular an autonomous robot or a magnetically guided robot), a camera or a drug delivery system. The drug delivery system may be suitable for delivering drugs, for example encapsulated drugs.
The passage may also be advantageous for additional uses. It may serve as a channel or it may provide space for placing an additional channel or lumen. Such a channel may e.g. be useful for preserving a blood circulation through the insertion instrument, e.g. when inserting the instrument into a cerebral artery. It may allow carrying a fluid (gas or liquid) or to add or remove substances or material through the insertion instrument.
It may e.g. allow a suction of matter through the same, for example a thrombus during thrombectomy. It may also be used for removing a sample taken during a biopsy.
The instrument may also comprise an additional lumen arranged or arrangeable within the passage. The additional lumen has an open distal end. Its proximal end may e.g. be connectable to a suction port in case of uses for thrombectomy. It may also lead to a vessel such as to allow blood flow from the proximal to the distal end.
In accordance with a first aspect of the invention, the length of the outer portion of the sheet along the extension direction can be controlled by moving the inner portion of the sheet by means of the second holding member. For example, the motion of the inner portion may be controlled via driving and/or via braking the second holding member. Preferably, the inner portion of the sheet is actively moved.
The second holding member is preferably designed and arranged to hold open the passage, in particular also in a bent state of the extension. This allows the insertion of an interior device, in particular a surgical, therapeutic or diagnostic instrument, a sensor, a robot, a camera or a drug delivery system.
The diameter of the passage may be chosen in accordance with the specific application of the device. For instance, suitable diameters for endovascular applications may lie in the range from 2 mm to 5 mm, while they may lie in the range from 5 mm to 25 mm for endoscopic applications.
Preferably, the second holding member comprises a winding device for winding up the inner portion of the sheet. This arrangement provides a small overall size of the second holding member.
The inner portion may be evertingly woundable about itself by the winding device. Therefore, when wound, a radial inner surface of the inner portion lies against a radial outer surface of the inner portion.
The winding device may comprise at least one driving wheel which is rotatable about a driving axis that is arranged transversely (i. e. at a non-zero angle) with respect to the extension direction, in particular perpendicular to the extension direction. The driving wheel may be mounted on a ball bearing or bushing and may be motorized by a motor. Brushless DC motors are especially suitable as they avoid noise and dust emission. The driving wheel and/or the motor may be forced against an inner or an outer surface of the inner portion of the sheet by at least one spring to ensure an even pressure as the thickness of the wound-up portion of the sheet changes.
The winding device preferably comprises at least two such driving wheels, wherein different circumferential portions of the inner portion of the sheet are in contact with respective driving wheels. This allows a more even winding up.
With further preference, the winding device also contains at least one positioning device which is designed and arranged such that the inner portion of the sheet is held in position between the at least one driving wheel and the positioning device. The positioning device may comprise at least one positioning wheel which is designed and arranged such that the inner portion of the sheet is held in position between the at least one driving wheel and the at least one positioning wheel. The positioning device, in particular the positioning wheel, may also be biased against the sheet by at least one spring. Such an arrangement with a winding device with a driving wheel and optionally a positioning wheel may also be advantageous for driving other growing robot devices, e. g. not necessarily having a passage as described above.
As an alternative to winding, the inner portion of the sheet may also be folded in order to control the length of the outer portion of the sheet.
The sheet is preferably made from a material that is essentially not stretchable; otherwise the sheet would rather stretch than evolve when it is inflated. The sheet may be made of a plastic film, for example LDPE or LLDPE, or it may be constituted as a coated fabric. It may also be 3D printed with flexible resins.
In a second aspect of the invention, the instrument also comprises, as in the first aspect,
In particular, the instrument may be designed as explained above.
According to the second aspect of the invention, the instrument further comprises at least one axially extendable stabilizing structure arranged inside the inner portion of the sheet in such a way that the inner portion of the sheet is prevented from closing the passage. The stabilizing structure may extend to the same extent as the outer tubular structure, thereby preventing the passage from closing, which facilitates the insertion of an interior device, in particular a surgical, therapeutic or diagnostic instrument, a sensor, a robot (in particular an autonomous robot or a magnetically guided robot), a camera or a drug delivery system.
The stabilizing structure may comprise a plurality of stabilizing rings which are arranged along the extension direction and, in particular, concentrically around a center line of the extension. Alternatively, the stabilizing structure may comprise at least one helical spring which extends along the extension direction and, in particular, surrounds a centerline of the extension.
The stabilizing rings or coils of the helical spring, respectively, may be connected to one another by at least one, preferably several controlling wires extending in the extension direction. Preferably, the at least one controlling wire extends through openings provided in the stabilizing rings or coils of the helical spring, respectively. By pulling or releasing the controlling wire at a proximal end of the instrument, the length of the extension can be controlled. Moreover, when several direction wires are present, the direction of a further eversion of the sheet at the distal tip can be controlled by selectively pulling or releasing the controlling wires at the proximal end of the instrument.
The helical spring and the controlling wires may be made of a metal, as for example nitinol or steel, or a plastic material. With preference, the controlling wires are essentially nonelastic in order to prevent a backlash.
The instrument may contain more than one stabilizing structure, as for example three helical springs. Each stabilizing structures may have a respective centerline extending along the extension direction, wherein the centerlines may be arranged excentrically with respect to a centerline of the extension.
In particular, when there are several stabilizing structures, inside at least one or all stabilizing structures, a respective additional fluid-tight tubular sheet may be arranged which is closed at a distal end of the stabilizing structure. These additional sheets are distinct from the tubular sheet and arranged inside the inner portion of the latter. By selectively controlling the fluid pressures inside the tubular sheets, the direction of a further eversion of the sheet at the distal tip can be controlled.
With further preference, the distal tip comprises a tip head which is attached to the stabilizing structure and arranged outside a chamber that is at least partially enclosed by the inner portion of the sheet and the outer portion of the sheet, wherein the tip head comprises a head opening forming a distal end of the passage. The tip head may add to the stability of the instrument at its distal tip.
The tip head may further comprise at least one measuring device for measuring a property of an inspected object inside a cavity, in particular at least one camera and/or at least one ultrasound probe. Other types of sensors such as pressure sensors, temperature sensors, optical sensors, e. g. for spectroscopic purposes, or electric or magnetic sensors are conceivable. Wires can be used to supply these measuring devices with energy and/or to transmit data measured by the measuring devices. The wires can be arranged, for example, along the controlling wires mentioned above. Alternatively, the wires may be arranged inside one of several helical springs whose centerlines are arranged excentrically with respect to a centerline of the extension.
The distal tip of the instrument may comprise at least one guiding wheel for guiding the sheet at its transition from its inner portion to its outer portion, wherein the guiding wheel is arranged inside the chamber that is at least partially enclosed by the inner portion of the sheet and the outer portion of the sheet.
Furthermore, the distal tip may comprise at least two, in particular four, guiding wheels which are rotatably arranged on a guiding ring that surrounds the passage. These guiding rings can aid the eversion of the sheet at the distal tip of the instrument.
The guiding wheel may be passively driven due to the evolving movement of the sheet between the guiding wheels and the tip head. Alternatively, the at least one guiding wheel may be actively driven, which further facilitates the eversion of the sheet at the distal tip of the instrument. Electrical power supply to the guiding wheels may be achieved through wires which can be arranged, for example, along the controlling wires mentioned above or inside one of several helical springs whose centerlines are arranged excentrically with respect to a centerline of the extension.
In a further aspect, the invention also relates to a set comprising an insertion instrument as disclosed above as well as at least one interior device provided for extending through the passage of the insertion instrument. In particular, the set may be a surgical set. The interior device may be a surgical, therapeutic or diagnostic instrument, a sensor, a robot (in particular an autonomous robot or a magnetically guided robot), a camera or a drug delivery system. The invention also refers to the use of a lumen formed within the passage of the insertion instrument for a carrying a fluid such as a suction fluid, e.g. during thrombectomy or as a transport channel, e.g. for transporting a biopsy sample during biopsy.
The invention will now be further explained with several embodiments which are shown in the following figures. While these insertion instruments are all embodied as surgical insertion instrument, the invention also encompasses non-surgical insertion instruments. In the drawings,
The surgical insertion instrument 50 shown in
The sheet 1 has a first annular end 12 that is fixed to the base member 24 which thereby forms a first holding member in terms of the present invention. The sheet 1 further comprises a second annular end 13 and a middle section 14 extending between the first annular end 2 and the second annular end 13. An outer tubular portion 16 of the middle section 14 extends along an extension direction D, from the base member 24 to a distal tip 7 of the instrument 50 where it transits into an inner tubular portion 18 arranged inside the outer tubular portion 16. The inner portion 18 and the outer portion 16 of the sheet 1 partially enclose a chamber 25 in which a fluid, in particular a gas, can be inserted. The base member 24 encloses a cavity 27 that is fluidly connected to the chamber 25. The base member 24 further contains a fluid inlet 26 through which the fluid can be entered into the cavity 27 and into the chamber 25.
Inside the cavity 27, two driving wheels 5 are arranged which are rotatable about a respective driving axis A (see
The winding device also contains four positioning wheels 32 which are arranged such that the inner portion 18 of the sheet 1 is held in position between the driving wheels 5 and the positioning wheels 32. The motors are forced against the inner portion 18 of the sheet 1 by springs 33 (not shown in
A helical spring 12 is arranged inside the inner portion 18 of the sheet 1. A proximal end 23 (see
The spring 20 provides a stabilizing structure which prevents the sheet 1 from closing the passage 19. This in turn allows a surgical instrument or a sensor to be inserted through the passage 19, even when the sheet 1 bends. Also, a lumen is formed or the passage can be used to place an additional, separate lumen. The lumen is useable for various purposes, e.g. for allowing blood flow, for carrying a fluid for suction, e.g. for removing a thrombus during thrombectomy or for carrying a biopsy sample. By pulling or releasing the controlling wire 22 at a proximal end of the instrument 50, the length of the extension can be controlled. By selectively pulling the controlling wires 22 at a proximal end of the instrument 50, even the direction of further eversion of the sheet 1 at the distal tip 17 can be controlled.
The distal tip 17 of the instrument 50 comprises a tip head 4 which is attached to the spring 20 and which is arranged outside the chamber 25. The tip head 4 further comprises a head opening 7 forming a distal end of the passage 19 as well as two cameras 8 and an ultrasound probe 9. The cameras 8 and the ultrasound probe 9 may be supplied with energy through supply lines that may extend through the openings 29.
In the second embodiment shown in
A third embodiment is displayed in
The coils 21 alternatively or additionally also might be connected to each other by the sheet 30.
By selectively controlling the gas pressures inside the additional sheets 30, the direction of further eversion of the sheet 1 can be controlled: Whereas
Instead of helical springs, the stabilizing structure of the fourth embodiment shown in
The embodiment depicted in
| Number | Date | Country | Kind |
|---|---|---|---|
| 21315059.2 | Mar 2021 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/057296 | 3/21/2022 | WO |
