Abstract:
The disclosure is directed to a cholangiography catheter insertion tool, or introducer. In the preferred embodiment, the tool comprises a hollow cylinder with an ovate directional aperture lying in the plane of a tangent to the cylinder and parallel to the longitudinal axis of the cylinder. Also disclosed is a method of using the tool.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention (Technical Field) 
     The present invention relates to a cholangiography catheter introducer article, and a method for its use. 
     2. Background Art 
     Increasingly, less invasive surgical procedures are supplanting the open surgical procedures of the past. In no area is this more apparent than in surgical removal of the gallbladder, or cholescystectomy, for cholecystitis (inflammation of the gallbladder or biliary ducts) or cholelithiasis (stones) of the gallbladder or biliary ducts. Laparoscopic (endoscopic insertion into the peritoneal cavity) cholescystectomy and its resultant decreases in morbidity, hospital stay, and recuperative time favor increased acceptance of this procedure by the surgical community. 
     Further, many, if not most surgeons versed in the laparoscopic procedure, prefer conducting cholangiography to define the ductal anatomy and identify common duct stones prior to transsection of anatomy. In this subprocedure, a transverse incision is made in the cystic duct. A cholangiography catheter led through an intraperitoneal trocar is passed through the incision into the cystic duct and subsequently into the common duct. 
     Cannulation of the cystic duct by the cholangiography catheter is often a difficult and tricky process. The catheter must first traverse an approximate right angle through the incision into the cystic duct, and a further approximate right angle bend into the common duct. The prior art has employed catheters of &#34;memory&#34; plastic with curved insertion portions. Alternatively, guidewires inside catheters have been used to properly cannulate the cystic and common bile ducts. Graspers, specially designed cholangiography guides, and conventional suction-irrigation cannulae have been used. 
     Needless to say, manipulation of catheters through trocars is difficult at best, and may occupy two or more surgical personnel. 
     SUMMARY OF THE INVENTION 
     Disclosure of the Invention 
     The present invention relates to a tool for inserting a catheter into a duct, the tool comprising an elongated tube having a longitudinal axis and telescopically positionable within a trocar. The elongated tube further comprises a curved distal end and an aperture disposed at said distal end. A catheter extends through the trocar, said elongated tube, and said aperture. 
     In the preferred embodiment, the aperture extends in a plane parallel to the longitudinal axis of said elongated tube and the aperture comprises an ovate aperture extending in a plane tangent to said elongated tube or ovate aperture at a range of angles 45° on either side relative to the tangent to the cylinder of said elongated tube. 
     The elongated tube and/or distal end may comprise an aluminum material, a stainless steel material, a thermoplastic or thermosetting plastic material, such as polypropylene material, or the like. The elongated tube preferably comprises a length in the range of between approximately 25 and 35 cm. 
     In alternative embodiments, the distal end may comprise a sharpened portion or a lanceolate portion. The distal end may comprise a removably attachable tip positionable on a rod which is telescopically positionable within the trocar. The distal end may comprise a notched flexible tube, curved and joined at said notches, or at least two joined units forming said curve. 
     The invention further relates to a method of performing cholangiography comprising the steps of making a transverse incision in a cystic duct; inserting a cholangiography catheter inserter into the incision; and inserting a cholangiography catheter through the inserter and into the cystic duct. The cholangiography catheter inserter preferably comprises an ovate aperture. The cholangiography catheter inserter may further comprise a distal end with a sharpened or lanceolate portion. 
     An object of the present invention is the provision of a cholangiography catheter insertion tool which is simple to use and directionally effective. 
     Yet another object of the present invention is the provision of a cholangiography catheter inserter tool which is easy and inexpensive to manufacture. 
     An advantage of the present invention is that it may be used with existing surgical tools. 
     Yet another advantage of the present invention is that it be fabricated of disposable materials. 
     Other objects, advantages, and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated into and form a part of the specification, illustrate several embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating a preferred embodiment of the invention and are not to be construed as limiting the invention. 
     FIG. 1 is a cutaway and phantom view of a prior art trocar, cannula, and catheter inserted into a cystic duct; 
     FIG. 2 is the preferred cholangiography catheter introducer of the invention; 
     FIG. 3 is the FIG. 2 embodiment of the invention rotated 90° to the right; 
     FIG. 4 is an alternative embodiment of cholangiography catheter introducer of the invention; 
     FIG. 5 is the FIG. 4 embodiment of the invention rotated 90° to the right; 
     FIG. 6 is a side view of an alternative tip embodiment of the invention; 
     FIG. 7 is a front view of the FIG. 6 embodiment; 
     FIG. 8 is an alternative multiple end piece embodiment of the invention; and 
     FIG. 9 is a front view of the FIG. 8 embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Best Modes for Carrying Out the Invention 
     FIG. 1, illustrating the prior art, shows trocar 10 in phantom as it might be inserted into the peritoneal cavity 24 prior to cholescystectomy. Trocar 10, usually of 5 or 10 mm diameter, is a cylinder comprising valve 12 for initiating and maintaining insufflation and permitting desufflation of CO 2  constituting the pneumoperitoneum. Ordinary suction-irrigation tool 14, comprising openings at both ends, is shown inserted in trocar 10. Suction-irrigation tool 14 is further depicted inserted into transverse incision 16 in cystic duct 20. Endoscopic catheter 18 is depicted as inserted in cystic duct 20 prior to commencement of cholangiography. 
     The insertion or introduction of catheter 18 into cystic duct 20, and ultimately into common bile duct 22 is, at best, a difficult and awkward maneuver. First, transverse incision 16 is made in cystic duct 20, usually with microscissors. Following the incision, suction-irrigation tool 14, having been passed through trocar 10, is inserted through incision 16. This insertion may be attended with difficulty due to an undersized or misplaced incision. Catheter 18 is then manipulated (sometimes by two or more surgical personnel) through suction-irrigation tool 14 into cystic duct 20. Catheter 18 must be sufficiently small and of the proper stiffness to negotiate the angular entrance required. Subsequent bending and manipulation is also required for entrance of catheter 18 into common bile duct 22. 
     FIGS. 2 and 3 depict the preferred cholangiography catheter introducer 26 of the invention. Tool 26 is generally 5 mm in diameter, corresponding to the smallest sized trocar with which it is to be used. In the event trocar 10 is of great internal diameter relative to the diameter of introducer tool 26, gaskets and other gas sealing means, as are well known in the art, may be used to prevent gas leakage and assure integrity of the pneumoperitoneum. 
     The introducer tool 26 of the invention comprises a cylinder which further comprises a hollow lumen. Tool 26 comprises a length in the range of between approximately 25 and 35 cm. 
     Distal end 31 of introducer tool 26 comprises ovate aperture 28 in communication with the lumen of the tool. The plane of aperture 28 may coincide with the plane tangent to the cylinder of tool 26, but may also lie 45° on either side of the plane. Ovate aperture 28 is created by bending tool 26 90° and serving the bend at the tangent plane. Spoon-like ovate aperture 28 and corresponding curve 29 thus form and serve as directional guides for proper catheter placement in the cystic duct 20. 
     As is apparent in FIGS. 2 and 3, the plane of ovate aperture 28 is preferably parallel to the longitudinal axis 30 of introducer tool 26. As is further apparent in FIGS. 2, 3, 5, 6, and 8, distal tip 31 may project substantially beyond a plane A--A&#39; tangent to the outside surface of the cylinder of tool 26. Further, a line normal to the plane of ovate aperture and passing through its center would also be normal to longitudinal axis 30. However, ovate aperture distal tip 31 of introducer tool 26 may further comprise a sharpened or lanceolate tip 32, as depicted in FIGS. 4 and 5. Such a tip facilitates entrance into transverse incision 16, especially when such incision is of insufficient width. 
     FIGS. 6 and 7 illustrate an alternative embodiment of the invention in which the introducer tool 26 comprises a removably attachable tip on rod 34, which rod 34 then fits within trocar 10. As can be appreciated by those skilled in the art, all of the embodiments shown in the drawings and those encompassed by the present invention could be either tips on a rod or integral with the rod. The embodiment of FIGS. 6 and 7 is preferably made of a flexible plastic material which can be cut to form two side notches 36 allowing the end to be curved over with the notches glued or otherwise joined together. A pointed tip 38 is useful for entry into traverse incision 16. 
     FIGS. 8 and 9 illustrate yet another alternative embodiment of tool introducer 26 in which two distal end pieces 40 and 42 are glued or otherwise joined together at juncture 44 to allow for a curved distal end. As can be appreciated by those skilled in the art, many types of junctures and shapes are possible with this multiple piece embodiment. 
     Introducer tool 26 may comprise several materials. Stainless steel and aluminum provide strength. On the other hand, since cholangiography normally requires removal of all unnecessary metal instruments from the field, the various plastics, generally including the thermoplastic and thermosetting plastics, are particularly suitable. Polypropylene is a preferred material which is approved by the Food and Drug Administration (FDA). The use of plastic introducer tools, which are disposable, further lessens the risk of infection, both to the patient and others. Other suitable materials will suggest themselves to those ordinarily skilled in the art. 
     Further, other uses and modifications of introducer tool 26 will suggest themselves to those ordinarily skilled in the art. For example, introducer tool 26 may be used in other surgical applications requiring catheter insertion, such as arterial or urethral catheterization. A variety of catheters may be used therewith, including balloon catheters. 
     Although the invention has been described with reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all applications, patents, and publications cited above, and of the corresponding application are hereby incorporated by reference.