Patent ID: 12232692

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Endoscopic devices are comprised of a handle section, an elongated insertion tube, and a distal tip at the end of the insertion section. An articulation section is often included at the distal end of the insertion section just before the distal tip to allow the distal tip to be deflected in order to change the angle of view of the imaging device and to aid in steering the insertion tube through bodily lumens to the location where the observations or procedure are to be carried out. To prevent bodily fluids, tissue, or debris from entering the insertion tube, it and the articulation section are encased in a sheath of polymeric material.

The present invention is directed to endoscopic devices that typically comprise at least an imaging device, e.g. a video camera and accompanying illumination means in the distal tip and optionally may include an articulation section that is activated by cables or wires that pass through the interior of the insertion tube from an articulation steering mechanism located in the handle section. Endoscopic devices frequently also comprise one or more working channels, through which surgical tools, e.g. forceps, snares, and therapy devices, e.g. lasers or RF generators, can be introduced from the handle section to the space beyond the distal tip in order to collect samples or carry out various procedures. In addition there are frequently channels for other purposes, e.g. irrigation water or air to clean the camera lens, gas for insufflation, dye for staining tissue, liquid for cooling (or heating), and gas or liquid for therapy, e.g. delivery of drugs or medicine.

In present day endoscopic devices each of the working channels and the channels for irrigation and insufflation are small tubes that run through the insertion tube from handle to distal tip. As an alternative to having separate tubes for each component or function, endoscopes may comprise a multi-lumen tube which contains separate lumens for each component. Also the optical fibers or electric wires for the illumination means and the power and signal wires to and from the camera pass through similar tubes. All of these individual tubes and the articulation cables or wires are tightly packed into the interior of the insertion tube.

FIG.5AandFIG.5Billustrate how the diameter of the insertion tube of an endoscopic device can be reduced by removing the water channel according to the present invention.

FIG.5Aschematically shows a transverse cross-section of a typical insertion tube at a location between the handle and the articulation section. In the figure can be seen how two illumination fibers28, camera cable44, two articulation cables42, a tube for a working channel50, and a tube for a water channel52are fit into the interior of insertion section14. The circumference of the insertion tube inFIG.5Ais denoted by reference symbol62.

FIG.5Bis a transverse cross sectional view of an insertion tube that, with the exception that there is no tube for a water channel, contains the same tubes, illumination fibers, and cables having the same diameters as those inFIG.5A. Water travels through the insertion tube inFIG.5Bthrough the empty spaces54(only one is marked inFIG.5B) between the other components passing through the insertion section. The circumference of the insertion tube inFIG.5Bis denoted by reference symbol64.

As can be seen fromFIGS.5A and5B, packing a plurality of tubes having a circular cross-section into a larger cylindrical tube inevitable means that there will be empty spaces between the tubes that are not utilized. The current invention makes use of these spaces to allow fluid to flow from the handle of the endoscope to the distal tip. In this way it is not necessary to have a separate irrigation/insufflation/cooling/dye/therapy channel and as a result the overall diameter of the insertion tube can be reduced as demonstrated by the comparison of circumference64inFIG.5Bwith circumference62(shown with a dashed line inFIG.5Bfor comparison) of the insertion tube ofFIG.5A. It should also be noted that the cross sectional area of each of the spaces54inFIG.5Bis less than the cross sectional area of the tube52(fromFIG.5A) that has been removed; however the total cross-section of all spaces54is equal to or larger than that of tube54. This means that at least the same amount of fluid can be delivered to the nozzle at the distal tip through the insertion tube inFIG.5Bas through that ofFIG.5Adespite the smaller overall diameter of the insertion tube.

Alternatively to reducing the diameter of the insertion tube, the invention allows the space formally occupied by the tube for a water channel to be utilized to pass additional components, e.g. an additional working channel, through the insertion tube.

FIG.1toFIG.4andFIG.6toFIG.9illustrate embodiments of an endoscope built according to the present invention.

FIG.1schematically shows a base part10of the handle section of an embodiment of an endoscopic device with the cover partially removed to reveal some of the interior components. Shown inFIG.1are the articulation handle12a, articulation drum12b, articulation cylinders12cand articulation cables or wires12dof articulation mechanism12; insertion tube14; illumination fibers and power and signal wires16; and gaskets18.

When the cover of the handle section is in place it presses against the gaskets18forming an air and water tight compartment15in the handle. In particular the two small O-rings seal the articulation cylinders and enable movement of the steering (articulation) cables or wires12dwithout leakage of fluid. An inlet port17allows water for irrigation or gas for insufflation to be introduced into this compartment. As will be described herein below, the water or gas flows out of the compartment in the handle into and through the insertion tube and exits the endoscope through a nozzle (or a set of nozzles) located on the distal tip.

Conventional endoscopic distal tips are made from a monolithic cylindrical block of metal or plastic comprising bores that pass through the block from its proximal end to its distal face to allow components of the insertion tube such as illumination fibers, camera cable, and working channels to pass from one side of the distal tip to the other via these bores. Additionally there can be cavities created on the front surface of the block to hold components such as a camera head or LEDs. For these distal tips the external surfaces of the block are smooth and shaped to minimize trauma as the endoscope is advanced to the site of the procedure.

In contrast to conventional distal tips, the distal tip of the present invention is comprised of two components: a) a block22comprising a pattern of alternating grooves32and lands34that are created on its outer surface; and b) a cap24, which fits tightly over the lands34to provide the distal tip with a smooth outer surface. The tops of lands34are pressed against the inside wall of cap24forming hermetic seals that effectively convert grooves32into closed channels through which water or gas flowing through the insertion tube can continue on its way to a nozzle on the distal end of the endoscope.

FIG.2schematically shows the distal end of an insertion tube14that can be connected at its proximal end to the handle section shown inFIG.1. The sheath that covers the insertion tube has been removed to reveal articulation section20and the distal tip comprised of block22and cap24.

Also seen inFIG.2are tabs46and the tapered proximal end36of block22. Tabs46symbolically represent one way of connecting block22of the distal tip to insertion tube14. The tabs can be attached by any method known in the art, e.g. welding or gluing, to the distal end of articulation section20and to the tops of the proximal ends of lands34on the outer surface of block22. In other embodiments the block acts as or is attached directly to the distal link of the articulation section. The function of tapered proximal end36will be described herein below.

FIG.3schematically shows an enlarged view of the distal tip shown inFIG.2with the cap24completely removed from the block22andFIG.4schematically shows cap24completely covering block22.FIG.6schematically shows the distal tip of the endoscopic device shown inFIG.4with part of the cap24cut away. In the embodiment shown inFIGS.2,3,4, and6a cable for camera26and illumination fibers leading to light ring58pass through insertion tube14.

FIG.7schematically shows the distal end of a second embodiment of an insertion tube that can be connected to the handle section shown inFIG.1.FIG.8andFIG.9respectively schematically show a transverse cross sectional view and a longitudinal cross sectional view through the distal tip of the endoscopic device ofFIG.7. In the embodiment shown inFIGS.7,8, and9, in addition to the components shown in the previous embodiment a working channel50passes through insertion tube14.

The method in which a nozzle (or nozzles) are created at the distal tip of the endoscopic device and the manner in which the fluid travels from the compartment in the handle to the nozzle is the same for both embodiments.

As shown inFIG.3, a circular portion at the center of the distal surface of cylindrical cap24is removed leaving a hole38surrounded by an annular curved portion40. As can also be seen in the same figure, a part35of the distal end of each land34is removed, With the insertion section14, including the articulation section, completely covered with the sheath56and the cap24in place over the block22as shown inFIGS.4,6,7, and9the inside of the endoscope is hermetically isolated from the outside with the exception of a small gap48between the front face of the block22and the bottom of curved surface40around the circumference of hole38in cap24. The shape of curved surface40causes the gap48to function as a circular nozzle30.

Water or gas introduced into the compartment in the handle enters the insertion tube14and flows through the empty spaces54between the tubes and cables that pass through insertion tube14and articulation section20. On reaching block22, the fluid travelling down the insertion tube the tapered proximal end36and is forced to the sides and through the grooves. The water or gas flows through grooves32and out of the distal end through circular nozzle30. The components of the distal tip are configured such that water or gas exiting through circular nozzle30is sprayed over the illumination fibers28and objective lens of camera26keeping them clean. It is noted that tapering the proximal ends of block22is one of several ways that could be employed to allow the fluid to flow from the handle at the proximal end to a nozzle or nozzles at the distal end of the endoscopic device.

FIG.6shows the distal tip of the endoscopic device shown inFIG.4with part of the cap24removed to reveal the lands34and grooves32on the outside surface of block22and the gap48between the front face of block22and the bottom of curved surface40of cap24that functions as circular nozzle30.

FIG.7schematically shows the distal end of an embodiment of endoscopic device. Seen in this figure is sheath56covering the insertion tube and distal tip14. A camera26, light ring58, and working channel50are seen on the front face of the distal tip. Gap48is seen between the bottom of the curved portion40of the cap24that covers the block22of the distal tip.

FIG.8schematically shows a transverse cross sectional view through the distal tip of the endoscopic device ofFIG.7. Seen in the figure are working channel50, a cavity26for a camera head, and light ring58. Also seen are the lands34and grooves32on the surface of the block22, the cap24that fits tightly over the lands and overlaps the sheath56, and articulation cables42.

FIG.9schematically shows a longitudinal cross sectional view of the endoscopic device ofFIG.7. Seen in this figure are articulation section20and articulation cables42. The distal end of each articulation cable42is bent to form a sort of tab46that is fixedly attached to the proximal end of block22, for example by soldering or welding, thereby attaching the distal tip22to the articulation section20. The proximal part36of block22is cut at an angle to allow water flowing through the insertion tube between the tubes and cables enclosed by sheath56to enter the grooves32between lands34and to flow through the grooves32to the curved annular end40of cap24that covers the grooves32and lands34. When water reaches curved annular end40it flows through gap48and is sprayed over the front face of block22exiting through hole38. Also seen are channels for the camera cable44and illumination fibers28, working channel50, and a cavity60into which a camera head can be inserted.

The embodiments described herein are configured to comprise a circular nozzle, i.e. a nozzle that creates a spray emitted in all (360 degrees) directions. In other embodiments the grooves32, lands34and hole38in the cap24can be configured to direct the liquid or gas to form one or more nozzles that will emit a spray having any desired angular spread.

It is noted that only very basic embodiments of an endoscopic device have been described herein in order to illustrate the principle of the invention. In addition to a working channel, camera and illumination means, the endoscope may comprise additional working channels, and other components located on the distal tip, e.g. ultrasound transducers. All of these require their own tube, cable, or wire that must be integrated into the interior of the insertion tube. In these embodiments, eliminating the need for a separate irrigation and/or insufflation channel by utilizing the spaces between the other tubes for the passage of water or gas as taught by the present invention will play an important role in reducing the overall diameter of the insertion tube.

Although embodiments of the invention have been described by way of illustration, it will be understood that the invention may be carried out with many variations, modifications, and adaptations, without exceeding the scope of the claims.