Resectoscope cutting electrode

[57] ABSTRACT

A resectoscope including a tubular sheath; an optical telescope comprising a tubular stem within the sheath, an eyepiece at the proximal end of the stem and an objective lens at the distal end of the stem; and a cutting electrode carried by and reciprocable along the telescope stem and comprising a tubular body, an electrode wire including a rectilinear first part extending through and insulated from the inner surface of the tubular body, a generally loop-shaped second part extending beyond the distal end of the first part and having a pair of electrically insulated arms and an uninsulated cutting element constituting a continuation of each arm and positioned in the field of vision of the telescope. Mounted on the tubular body is a saddle unit comprised of an arcuate first member secured to the body, an arcuate second member affixed to the first member and embracing the telescope stem and slidable therealong, and a pair of arcuate third members which are disposed and attached to opposite sides of the second member. A portion of each arm is retained in a corresponding third member whereby the arms are adequately supported and rendered more stable against undesirable flexing, bending and/or deformation.

Claims, 8 Drawing Figures

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PATENTED *0014 BT3

3,752.159

SHEET 1 OF 2

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FIG 2

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FIG 5

INVENTOR.

REINHOLD D. WAPPLER

Arrower

PATENTEfiMCUBH

3.752.159

SHEET 2 Of 2

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FIG. 6

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FIG. 8

INVENTOR.

REINHOLD D. WAPPLER

BY

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Arra/uvey

3,752,159

RESECTOSCOPE CUTTING ELECTRODE

BACKGROUND OF THE INVENTION

This invention relates to the art of resectoscopes and, more particularly, to a resectoscope cutting electrode embodying improved features of design and construction.

A resectoscope usually consists of a number of devices and parts including a tubular sheath; an optical telescope having a tubular stem within the sheath, an eyepiece at the proximal end of the stem and an objective lens at the distal end of the stem; a discharge conduit for withdrawing irrigating fluid and entrained material; and a cutting electrode reciprocable along the telescope stem and having a cutting element at its distal end and normally in the field of vision of the telescope.

The cutting electrode of a great many resectoscopes which have been used over the years (hereinafter referred to as “prior art cutting electrodes”) includes an elongated rectilinear tubular body and an electrode wire extending through the body and having a fragile, forked, distal extension terminating in a cutting element. In operating the resectoscope, the forked extension is protracted beyond the telescope and the protective confines of the sheath. As a consequence, the forked extension is virtually unprotected and is unsupported, except for its connection to the tubular body; and its arms and cutting element are exposed and often subjected to bending and other distorting stresses which frequently deform these parts to the extent that they cannot be used effectively. Such deformation is objectionable for a number of reasons. For one thing, substantial upward deformation results in the cutting element being placed out of the visual field of the telescope. Lateral deformation often causes undesirable friction during reciprocation of the cutting electrode along its design path. Moreover, deformation which allows the uninsulated cutting element to come too close to associated electrically conductive parts, during use, causes creation of dangerous electrical arcs with resultant damage to the instrument and possible injury to a patient.

As will be apparent from the annexed drawings and the detailed description appearing further along herein, the resectoscope cutting electrode of this invention is devoid of the stated objections to and disadvantages of prior art cutting electrodes.

SUMMARY OF THE INVENTION

A resectoscope embodying this invention is provided with a tubular sheath; an optical telescope having a tubular stem which is positioned within the sheath, an eyepiece at the proximal end of the stem and an objective lens at the distal end of the stem; a cutting electrode device carried by and reciprocable along the stem and having a tubular body, an electrode wire including a first part extending through and electrically insulated from the body, a generally loop-shaped second part extending beyond the distal end of the body and consisting of a pair of electrically insulated arms and an uninsulated cutting element which is a continuation of each arm; and a saddle unit which is secured to the distal portion of the body, is coupled to and slidable along the telescope stem and is joined to and supports the arms. The sheath, telescope and parts of the cutting electrode, except for the saddle unit, may be of any desired known construction. The essence and heart of the invention reside in the construction and cooperative relationship of the saddle unit with other parts, as will be explained in the ensuing detailed description.

It is the principal object of this invention to provide a resectoscope cutting electrode embodying novel and improved features of design and construction.

Another object of this invention is to provide a resectoscope cutting electrode, which includes a body, an electrode wire having a generally loop-shaped part extending beyond the distal end of the body and consisting of a pair of arms and a cutting element, with means for supporting the arms intermediate their ends and rendering the loop-shaped part more stable against undesirable flexing, bending and/or deformation.

Another object of this invention is to provide a resectoscope including an electrode having a cutting element and having its parts so constructed and arranged as to effectively minimize the possibility of electric arcing between the cutting element and other parts during use.

It is a further object of this invention to provide a cutting electrode which may be advantageously employed with existing resectoscopes as well as with new resectoscopes.

A still further object of this invention is the provision of a cutting electrode of the character indicated which is simple and compact in design; which is rugged and durable in construction; which is reasonable in material and manufacturing costs; and which is free of the objections to and disadvantages of prior art cutting electrodes.

The above-stated objects and additional objects, as well as the advantages of this invention, will be readily manifest to persons trained in the art from the following detailed description and the accompanying drawings which respectively describe and illustrate a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, wherein like reference characters denote like parts in the several views:

FIG. 1 is a view in side elevation of a resectoscope that is equipped with an improved cutting electrode according to this invention, the distal portion of the sheath being shown in central vertical cross section for better illustration of parts therein;

FIG. 2 corresponds to the right end portion of FIG. 1 and illustrates certain parts in another relative position;

FIGS. 3, 4 and 5 are views in enlargement taken along lines 3—3, 4—4 and 5—5, respectively, of FIG. 1;

FIG. 6 is an enlarged view in side elevation of a cutting electrode which is also shown in earlier views;

FIG. 7 is an isometric view of a saddle unit which is part of the cutting electrode; and

FIG. 8 is a view in enlargement taken along line 8—8 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference is first had to FIGS. 1 through 5 which illustrate a resectoscope R that is comprised of an assembly A, a sheath S, an optical telescope T, a conduit C and a cutting electrode E which includes a saddle unit U.

3,752,159

Assembly A consists of a collection of known parts for supporting, operating and/or controlling other parts in a manner well known to the art. Assembly A is incorporated in certain commercially available resectoscopes which are manufactured and marketed by American Cystoscope Makers, Inc., having a place of business at Pelham Manor, New York.

Sheath S is tubular, is made of a suitable synthetic plastic material and is affixed at its proximal end to assembly A. The sheath serves a plurality of functions including those of transmitting irrigating fluid into a body passage or cavity into which it has been inserted, and protectively housing the various devices which are positioned therein.

Telescope T is conventional in design and construction and includes a tubular stem 10, an eyepiece 11 at the proximal end of the stem and an objective lens (not shown) at the distal end of the stem. As shown in FIG. 1, stem 10 extends through assembly A and into sheath S, terminating adjacent the distal end of the sheath.

Conduit C is disposed along stem 10 and is secured thereto by soldering or in any other manner known to the art. The conduit is utilized to withdraw irrigating fluid previously admitted by way of the sheath and entrained material. As shown in FIG. 1, the distal end of conduit C is located rearward of the distal end of the telescope stem. Also secured to the telescope stem and parallel to conduit C is a conventional tube (not shown) for guiding cutting electrode E.

Cutting electrode E will now be described, having reference to FIGS. 6, 7 and 8. The cutting electrode comprises a thin wall, rectilinear, metallic, tubular body 12 and an electrode wire W having a rectilinear portion 13, which extends through body 12, and a generaly loop-shaped portion 14, which extends beyond the distal end of the body and terminates in an arcuate cutting element 15. All of wire W, except for its proximal end portion 16 (FIG. 6) and cutting element 15, is ensheathed in a suitable electrical insulating synthetic plastic material 17.

The loop-shaped portion of the electrode includes a pair of symmetrical arms 18, each consisting of an upwardly and outwardly projecting part 19 and a rectilinear part 20. Arm parts 19 are forwardly divergent while arm parts 20 are spaced apart and parallel.

Means are provided in the form of a saddle unit U which is preferably made of a plurality of metallic arcuate members consisting or an arcuate first member 21, an arcuate second member 22 and a pair of arcuate third members 23. Arcuate member 21 is located along the distal end portion of tubular body 12 and is secured thereto, preferably by soldering. Arcuate member 22 is positioned above and affixed to arcuate member 21 in any desired suitable manner. Arcuate members 23 are disposed and affixed to opposite sides of arcuate member 22. The several arcuate members 21, 22 and 23 are spaced from each other in parallel relationship. The major portion of arcuate member 22 projects forward of the distal end of tubular body 12 and is bifurcated longitudinally to obtain a pair of legs 24. Each leg carries a corresponding arcuate member 23. Legs 24 also define a slot 25 to permit proper vision by means of telescope T regardless of the position of the electrode relative to the telescope during normal use.

Arcuate members 23 are somewhat greater than 180° in transverse cross section. These members are in the nature of clips and, as illustrated in FIGS. 6 and 8, each member 23 receives and retains a portion of a corresponding arm part 20 whereby to afford adequate support to arms 18 and effectively restrain the arms against the aforementioned objectionable bending and resultant deformation.

The several arcuate members 21, 22 and 23 are thin walled. However, due to the spacing provided by the combined thicknesses of arcuate members 22 and 23 and insulation 17 (see FIG. 8), the possiblity of the referred-to electrical arcing between cutting element 15 and telescope stem 10 is substantially reduced.

Arcuate member 22 is relieved, i.e., cut out, along one side of its proximal end to accommodate the distal end portion of conduit C when electrode E is in retracted position (FIG. 1). The portion of member 22 above member 21 may be tubular, depending on the available space in the resectoscope. Accordingly, the term “arcuate” as used in reference to member 22 in this description and in the claims in intended to include such a member which may be at least partly tubular.

Referring again to FIGS. 1 and 2, FIG. 1 illustrates the relative position of the parts when electrode E is in fully retracted position while FIG. 2 illustrates the relative position of the parts when the electrode is in fully protracted position. The resectoscope is operated in the usual manner to sever selected tissue in a body passage or cavity by reciprocating electrode E under conditions of illuminated vision and with the aid of a high frequency current applied to wire W and effective in cutting element 15.

Based on the foregoing, it is believed that the construction, operation, objects and advantages of my present invention will be readily comprehended by persons skilled in the art, without further description. It is to be clearly understood, however, that various changes in the construction described above and illustrated in the drawings may be made without departing from the scope of the invention, it being intended that all matter contained in the description or shown in the drawings shall be interpreted as illustrative only and not in a limiting sense.