WO1998033445A1

WO1998033445A1 - Single arm electrocautery probes and probes with upper and lower operating surfaces for use with a resectoscope

Info

Publication number: WO1998033445A1
Application number: PCT/US1998/002201
Authority: WO
Inventors: Kevin F. Hahnen; Boris Kessler
Original assignee: Symbiosis Corporation
Priority date: 1997-02-05
Filing date: 1998-02-05
Publication date: 1998-08-06

Abstract

An electrocautery probe (112) has a single probe arm (123), and an electrode (122) according to a first aspect of the invention. The electrode includes one end attached to the probe arm and a free end. In two different embodiments, the electrode is a wedge with a substantially triangular cross section and a roller barrel. In another embodiment, the free end of the electrode which may be planar, pointed or rounded, rises higher than the attached end of the electrode. A planar free end may be inclined in either the proximal or distal direction. In another aspect of the invention, full loop electrodes are provided including a full loop electrode which has a working surface that extends below the axis of the cautery probe, a working surface which extends above the axis of the cautery probe, composite full loop electrodes wherein the upper working surface and the lower working surface have different morphology, combined full loop and roller electrodes wherein one of the upper and lower portions of the loop serves as the axle for a roller electrode, and bifurcated full loop electrodes wherein the upper working surface and the lower working surface can be independently energized.

Description

SINGLE ARM ELECTROCAUTERY PROBES AND PROBES WITH UPPER AND LOWER OPERATING SURFACES FOR USE WITH A RESECTOSCOPE

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates broadly to endoscopic instruments. More particularly, this invention relates to electrocautery probes for use with a resectoscope.

2. State of the Art

Electrosurgical resection is a procedure in which damaged or enlarged tissue is excised with an electrocautery probe. Transurethral resection is an electrosurgical procedure in which a portion of the prostrate is excised by means of an instrument passed through the urethra. Endometrial ablation is an electrosurgical alternative procedure to hysterectomy for women with menorrhagia (abnormal or excessive uterine bleeding) . In both procedures, the instrument typically used is called a resectoscope or hysteroscope. Prior art Figure 1 shows a typical resectoscope 10 with an electrocautery probe 12. The resectoscope 10 includes a distal guide tube 14 and a body 16 having a stationary handle portion 17 and a movable handle portion 19. A scope 18 is inserted through the guide tube 14 and is provided with a proximal eye piece 20 for viewing the interior of the bladder or other operative site. The scope has a longitudinal axis L. The cautery probe 12 has a distal electrode 22 which is mounted between a pair of arms 23, 25 and is situated in front of the scope 18. The arms 23, 25 extend proximally on either side of the scope and angle downward to be joined at their proximal ends to an electrode lead 27 situated beneath the scope. The electrode lead 27 slidably extends through the housing where at its proximal end the electrode lead is coupled to a wire 24 which is further coupled to a source of cautery current (not shown) . A mounting sleeve 29 is provided on the probe 12 for slideably coupling it to the guide tube 14. The mounting sleeve 29 is typically located at the point where the arms 23, 25 are joined to the electrode lead 27. The stationary and movable handle portions 17, 19 are generally capable of axially sliding the probe 12 and its distally mounted electrode 22 relative to the guide tube 14.

The resection procedure involves applying a cauterizing current to the electrode 22 and moving the electrode slowly through or over the prostate or endometrium while viewing the tissue through the scope 18. Thermal energy is applied through the electrode to the prostate or the endometrium so that tissue is excised. The resectoscope and cautery probe are also useful in other procedures for resecting the uterus, ureter, or renal pelvis .

Known electrodes for use in resectoscopes are available in many different shapes and sizes. U.S. patent 4,917,082 to Grossi et al . , for example, discloses several embodiments of a resectoscope electrode including a coagulating electrode, a knife electrode, a punctate electrode, and a roller electrode, among others. Electrodes for use with resectoscopes are also widely available from Olsen Electrosurgical, Inc., Concord, California. They are available as blades, needles, balls, loops, spear tips, flexible wires, semi-circular wires, hooks, spatulas and blunt tips.

Most of the known electrodes extend downward from a pair of probe arms and present a single working surface which is located below the axis of the probe arms and below the axis of the scope. Thus, in order to operate on tissue which is located above the probe arms, the entire resectoscope must be rotated 180° to bring the working surface of the electrode in contact with the tissue. U.S. Patents Number 5,007,907 to Nishigaki et al . and Number 5,196,011 to Korth et al . disclose electrodes which are suspended from a single probe arm. Nishigaki et al . discloses a special probe arm which is located above the scope and which has a loop which extends below the axis of the probe arm. Korth et al. discloses an electrode in the shape of a triangle which is suspended at its vertex from a single probe arm. While these patents would appear to show "full loop" electrodes, the electrodes shown do not have upper and lower working surfaces .

In addition, while differently shaped electrodes are utilized for various different procedures, electrodes of a given shape have a useful surface area limited by the space between the two arms on which they are mounted, and the space between the two arms is limited by the openings through which the instrument is inserted to reach the surgical site. A small surface area, however, compromises the effectiveness of the electrode as a coagulating tool. Thus, in a prostatic resection procedure, it is not uncommon that 80% of the time devoted to the procedure is used to coagulate the prostate and stop it from bleeding. In addition, in many procedures it would be desirable if a single electrode could be sufficiently versatile so as to adequately perform resection, general coagulation, spot coagulation, and tissue sculpting. However, known electrodes are not so versatile, and often multiple electrodes must be used in a single procedure to perform the different functions.

Another difficulty encountered in procedures utilizing electrocautery probes is when the electrocautery probe is moved distally relative to the scope, the arms of the probe tend to occlude the view of the physician through the lens of the scope of the areas lateral of the arms and the electrode. However, procedures utilizing a resectoscope are often involved in resecting and coagulating very delicate tissues in the narrow confines of the urinary and reproductive tracts, and the lower alimentary canal. Therefore, it is important for the physician to have, as much as possible, an unobstructed view through the scope.

One conceivable manner of reducing view obstruction, which is the subject of this invention as disclosed in great detail hereinafter, is to utilize an electrocautery cautery probe having only a single arm to thereby provide greater visibility to the surrounding tissue and to the points of contact between the electrode and the tissue. While the prior art literature does include a few probes having a single arm, it would appear that no commercial devices have incorporated these designs because the designs of the literature include substantial drawbacks. In particular, the single arm probes of the prior art have restricted use and are not at all versatile. For example, U.S. Patent No. 5,007,907 to Nishigaki et al . discloses an electrocautery probe with a single probe arm having a centrally mounted full loop electrode. The probe arm extends along the top of the scope and does not join an electrode lead, but rather is provided with a female threaded portion for electrically coupling to a male threaded portion of an electrode driving shaft. This unconventional configuration diminishes the desirability of the probe, as typical resectoscopes are adapted for slidably receiving an electrode lead beneath the scope and resectoscopes are not provided with driving shafts having threaded couplings. Therefore, the single armed electrocautery probe of Nishigaki et al. cannot be used with standard resectoscopes .

U.S. Patent No. 5,196,011 to Korth et al . ostensibly also shows an electrocautery probe with a single arm having a triangular-shaped full loop electrode centrally mounted on the arm and also having a depth gauge coupled to the arm. However, no connection is shown between the probe arm and the resectoscope. Therefore, one can speculate that the probe arm is arguably side mounted, as shown with respect to the multiple arm embodiments in Korth et al., or is top or bottom mounted with no enablement being provided for those possibilities. If the electrocautery probe is intended to be side mounted on the resectoscope, the electrode, being centrally mounted on the probe, would be located substantially off center from the scope, and, as a consequence, a lateral portion of the electrode would be out of view of the physician. Such an electrocautery probe would be dangerous to use because, as stated above, the physician requires a clear view of the tissue coming into contact with the electrode. If the electrocautery probe is intended to be top mounted, i.e., in vertical alignment with a longitudinal axis of the scope, the probe would not be usable with standard resectoscopes. If the electrocautery probe is intended to be bottom mounted in alignment with a longitudinal axis of the scope of the instrument, the electrode would extend too low, out of the view of the physician. As a result, utilization of the non-enabled single arm embodiment of Korth et al . is problematic regardless of how mounted.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a versatile electrocautery probe having an electrode adapted for tissue resection and tissue sculpting.

It is also an object of the invention to provide a versatile electrocautery probe having an electrode adapted for use for coagulation and spot coagulation.

It is another object of the invention to provide an electrocautery probe having an electrode having a relatively larger useful surface area than prior art electrodes of the similar size and shape.

It is a further object of the invention to provide an electrocautery probe which enables a physician to have relatively greater visibility of the surgical site.

Another object of the invention is to provide an electrode having upper and lower operating surfaces for use in an electrocautery probe with a resectoscope.

A further object of the invention is to provide an electrode having upper and lower operating surfaces of different morphology for use in an electrocautery probe with a resectoscope,

Yet another object of the invention to provide an electrode having upper and lower operating surfaces which can be separately energized for use in an electrocautery probe with a resectoscope.

In accord with these objects which will be discussed in detail below, various electrocautery probes are provided. According to a first aspect of the present invention, a single probe arm having an electrode is provided. The electrode includes one end attached to or adjacent to the probe arm and a free end. According to a preferred embodiment of the invention, the electrode is a loop electrode, preferably having a substantially triangular cross section. According to the preferred embodiment, the loop extends downward from the probe arm and then loops upward with the free end of the loop extending higher than the horizontal plane through the probe arm. According to another embodiment of the invention, the electrode is a roller barrel electrode supported by the single probe arm. Regardless of whether the electrode is a loop or roller barrel, the free end of the electrode may be planar, pointed, or rounded. Where the free end of the electrode is planar, it may be inclined in a lateral, proximal, or distal direction. The electrocautery probe is preferably adapted to fit into a standard resectoscope without modification of the resectoscope.

It will be appreciated that the electrode can be used for both cautery cutting and coagulation in the same manner as a typical electrode. It will also be appreciated that the electrocautery probe includes additional features and substantial advantages over electrocautery probes having two arms. First, with only one arm, the electrocautery probe does not interfere much with the physician' s view through the lens of the resectoscope, and thereby provides a clearer view to cautery site. Second, with a free end the electrode of the invention has an increased usable surface area, and is able to resect and coagulate along the entire length of the electrode including at the free end. Third, the free end of the electrode can be used for spot coagulation by rotating the electrode so that only the free end is touching the tissue. Fourth, the free end of the electrode can be used for tissue sculpting and for resecting tissue in narrow areas; i.e., tissue in the area of bladder neck and the verumontanum.

According to a second aspect of the invention, various full loop electrodes are provided including a full loop electrode having a working surface which extends below the axis of the cautery probe and a working surface which extends above the axis of the cautery probe, composite full loop electrodes wherein the upper working surface and the lower working surface have different morphology, combined full loop and roller electrodes wherein one of the upper or lower portions of the loop serves as the axle for a roller electrode, and bifurcated full loop electrodes wherein the upper working surface and the lower working surface can be independently energized.

The electrodes according to the second aspect of the invention permit resection of upper and lower prostate lobes without requiring inversion of the resectoscope, thereby shortening the time for the procedure. In addition, the full loop electrodes with different upper and lower morphologies provide additional treatment options while also reducing the time for the procedure. Furthermore, the bifurcated full loop electrodes provide the ability to use different power settings for the upper and lower working surfaces. Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.

Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures .

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a prior art resectoscope with an electrocautery probe having a loop electrode;

Figure 2 is an enlarged broken perspective view of the prior art electrocautery probe of Figure 1;

Figure 3 is a perspective view of resectoscope with an electrocautery probe according to a first embodiment of the invention;

Figure 4 is an enlarged broken perspective view of the distal end of the electrocautery probe of Figure 3;

Figure 5 is an enlarged broken front view of the electrode of the electrocautery probe of Figure 3;

Figure 6 is an enlarged broken front view of a second embodiment of an electrode for an electrocautery probe according to the invention;

Figure 7 is an enlarged broken front view of a third embodiment of an electrode for an electrocautery probe according to the invention;

Figure 8 is an enlarged broken front view of a fourth embodiment of an electrode for an electrocautery probe according to the invention;

Figure 9 is a cross-section across line 9-9 in Figure 8; Figure 10 is an enlarged broken front view of a fifth embodiment of an electrode for an electrocautery probe according to the invention;

Figure 11 is an enlarged broken perspective view of the distal end of an electrocautery probe according to a sixth embodiment of the invention;

Figure 12 is an enlarged broken front view of the electrode of the electrocautery probe shown in Figure 11;

Figure 13 is an enlarged broken perspective view of the distal end of an electrocautery probe according to a seventh embodiment of the invention;

Figure 14 is an enlarged front view of the electrode of the electrocautery probe shown in Figure 13;

Figure 15 is a perspective view of an eighth embodiment of an electrode for an electrocautery probe according to the invention;

Figure 16 is an enlarged front view of the electrode shown in Figure 15;

Figure 17 is an enlarged front view of a ninth embodiment of an electrode for an electrocautery probe according to the invention;

Figure 18 is an side elevational view of the electrode shown in Figure 17; and

Figure 19 is an enlarged broken perspective view of the distal end of an electrocautery probe according to a tenth embodiment of the invention. Figure 20 is an enlarged broken perspective view of the distal end of an electrocautery probe incorporating a first embodiment of a full loop electrode according to the invention;

Figure 21 is a view similar to Figure 20 of an alternate first embodiment of a full loop electrode according to the invention;

Figure 22 is an enlarged perspective view of a second embodiment of a full loop electrode according to the invention wherein the upper working surface and the lower working surface have different morphologies;

Figure 23 is an enlarged perspective view of a third embodiment of a full loop electrode according to the invention wherein the upper working surface and the lower working surface have different morphologies;

Figure 24 is an enlarged end view of a fourth embodiment of a full loop electrode according to the invention wherein the upper working surface and the lower working surface have different morphologies;

Figure 25 is an enlarged end view of a fifth embodiment of a full loop electrode according to the invention wherein one of the upper or lower portions of the loop serves as the axle for a roller electrode; and

Figure 26 is an enlarged broken perspective view of the distal end of an electrocautery probe incorporating a sixth embodiment of full loop electrode according to the invention wherein the upper working surface and the lower working surface can be independently energized. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to Figure 3, a resectoscope 110 is provided with an electrocautery probe 112 according to the invention. The electrocautery probe 112 has an electrode 122 mounted at the distal end of a conductive probe arm 123. The probe arm is preferably covered in an insulating material 125, such as PTFE. The probe arm 123 is joined at its proximal end to an elongate electrode lead 127, and a resectoscope mounting sleeve 129 coupled to the probe arm is provided preferably at the location where the probe arm 123 is joined to the electrode lead 127. The probe 112 is coupled to a guide tube 114 of the resectoscope 110 at the mounting sleeve 129. The electrode lead 127 extends under the guide tube 114 and slidably further extends through a housing 116 of the resectoscope. The electrode lead 127 is covered in an insulative sheath, and has an exposed proximal end 127a for connection to a wire 124 which is coupled to a cautery supply (not shown) . The probe arm 123 includes an upward bend 123a such that a distal portion of the probe arm extends substantially along the guide tube 114. A scope 118 extends through the guide tube 114, which has at its proximal end an eyepiece 120 through which to look through the scope. The housing 116 includes a stationary handle 117 and a movable handle 119 for moving the scope 118 and the probe 112 proximally and distally relative to the stationary handle 117.

Still referring to Figure 3, several planes are defined for reference: a vertical plane V passes through line L_v and the longitudinal axis L_A of the scope, and a horizontal plane H passes through line L_H and the longitudinal axis L_A of the scope. It will be appreciated that the horizontal and vertical planes shall remain as defined with respect to L_H, Ly, and L_A regardless of the whether the resectoscope is rotated into an orientation different from the one shown in Figure 3. Therefore, for purposes herein, all described horizontal planes are parallel to the horizontal plane H and all described vertical planes are parallel to the vertical plane V, and are not restricted to common definitions. It will be appreciated that in a typical resectoscope, the stationary handle 117 is bisected by the vertical plane V.

Referring to Figures 3, 4, and 5, according to a first embodiment of the invention, the electrode 122 is a loop electrode. The electrode 122 includes an attached end 132 coupled to the distal end 124 of the probe arm 123, and a free end 134. The electrode 122 loops downward from the attached end 132 to a lowest portion 135 and then loops upwards to the free end 134. The free end 134 preferably lies in substantially the same horizontal plane H as the attached end 132. The electrode 122 is preferably oriented in an orthogonal manner to the distal end 124 of the probe arm 123; i.e., preferably all of the electrode is seen through the scope. The electrode 122 is preferably sized, shaped, and situated such that the lowest portion 135 of the electrode is at the lateral midpoint 135a of the electrode and such that the electrode is substantially aligned with the longitudinal axis L_A of the scope 114; i.e., a line N vertically normal to the longitudinal axis L_A will intersect the electrode 122 at approximately the lateral midpoint 135a. It will be understood that the lowest portion 135 may also be situated, if desired, at a position other than at the lateral midpoint 135a of the electrode 122. The electrode 122 is preferably formed from a bent and shaped portion 140 of the probe arm 123 adjacent the distal end 124, but may also be formed of a separate piece of metal and attached to the distal end 124 of the probe arm 123, for example by welding. The distal end 124 of the probe arm 123 does not intersect the vertical plane V.

The electrode 122 preferably includes a substantially triangular cross-section along a majority of its length, as shown at 138 and described in detail in U.S. Patent #5,569,244. The free end 134 of the electrode 122 is preferably planar, and may be inclined in a lateral, proximal or distal direction relative to the arm 123. Referring to Figure 4, the free end 134 is shown horizontally planar. With reference to Figures 5 through 9 other exemplary embodiments of the electrode are shown. In Figure 5, the electrode 122a has a free end 134a outwardly inclined, thereby resulting in a lateral surface 136a. In Figure 6, the electrode 122b has a free end 134b having an inwardly inclined surface 136b, and a peripheral, preferably knife-sharp, edge 137b. In Figures 7 and 8, the electrode 122c includes a free end 134c which is distally inclined, resulting in a distal surface 136c. In Figure 9, the free end 134d of the electrode 122d is rounded.

It will be appreciated that in each of the embodiments the electrode can be used for both cautery cutting and coagulation in the same manner as a typical electrode. It will also be appreciated that the electrocautery probe includes additional features and substantial advantage over electrocautery probes of the prior art which include two arms. First, with only one arm, the electrocautery probe does not interfere much with the physician' s view through the lens of the resectoscope, and thereby provides a clearer view to cautery site. Second, with a free end the electrode of the invention has an increased usable surface area, and is able to cauterize and coagulate along the entire length of the electrode including at the free end. Third, the free end of the electrode can be used for spot coagulation by rotating the electrode so that only the free end is touching the tissue. Fourth, the free end of the electrode can be used for tissue sculpting and for resecting tissue in narrow areas; i.e., tissue in the area of bladder neck and the verumontanum.

Turning now to Figures 10 and 11, a preferred embodiment of an electrocautery probe 212, substantially similar to the first embodiment of the invention, is shown. The electrocautery probe 212 includes a probe arm 223 having an electrode 222 coupled thereto. The electrode 222 has an attached end 232 coupled to the distal 224 end of the probe arm 223, and a free end 234. The electrode 222 loops downward from the attached end 232 to a lowermost portion 235 and then back up to terminate in the free end 234 which extends a distance D higher than the attached end 232. The distance D is typically 0.10 inches, but may be longer or shorter. As such, the attached end 132 is located in a horizontal plane Hi which is situated between a horizontal plane H₂ passing through the free end 234 and a horizontal plane H₃ passing through the lowermost portion 235, wherein each of the horizontal planes Hi, H₂, and H₃ are parallel to the horizontal plane H shown in Figure 3. Preferably the free end 234 terminates in a pointed tip 238, but may be rounded or planar, as described above.

It will be appreciated that the extension of the free end 232 beyond the horizontal plane Hi of the attached end 234 allows the free end of the electrode to resect in narrow areas. It will also be appreciated that the pointed tip 238 of the electrode 222 provides enhanced ability to sculpt and resect tissue in exacting procedures. Furthermore, the use of a single arm and the extension of the free end enable larger and deeper resections .

Referring to Figures 12 and 13, another embodiment of an electrocautery probe 312, substantially similar to the first embodiment of the invention, is shown. The electrocautery probe 312 includes a roller bar electrode 322 approximately 2.5 mm long and having a central bore 342. The electrode 322 is preferably rotatably mounted on a bent axle portion 340 of the probe arm 323 extending through the central bore 342, and retained on the bent axle portion 340 by enlarging and/or bending the end 341 of the bent axle portion. The electrode may also be mounted on a conductive axle (not shown) coupled to the distal end 324 of the arm 323, for example, by welding. The electrode 322 is mounted such that substantially all of the electrode is visible through the scope. The electrode has a first end 332 adjacent the distal end 324 of the probe arm 323 (also referred to as "attached" to the distal end 324, even though the roller bar is rotatably mounted), a free end 334, and a circumferential outer surface 336. The outer surface 336 of the electrode 322 may be smooth or may be provided with a plurality of grooves. The free end 334 is preferably substantially planar and orthogonal to the outer surface 336.

It will be appreciated that the free end 334 of the roller bar electrode 322 provides an approximately fifty percent or greater increase in the surface area usable for tissue vaporization and coagulation and further permits the electrode to vaporize and coagulate in three planes orthogonal to each other: a substantially horizontal plane (parallel to the horizontal plane H shown in Figure 3) under or over the roller, a substantially vertical plane parallel to the surface of the free end 334 of the roller bar electrode 322 (and parallel to the vertical plane V shown in Figure 3) , and a vertical plane in front of the roller (orthogonal to both the vertical and horizontal planes, V and H) .

Referring to Figures 14 through 18, other embodiments of a roller bar electrode are shown. As seen in Figures 14 and 15, the free end 334a of the electrode 322a may be substantially rounded, and, as such, the free end is provided with an increased surface area for coagulation. As seen in Figures 17 and 18, the free end 334b of the electrode 322b may be substantially conical. The conical free end 334b may be used for coagulation along a majority of its surface, and for spot coagulation at the vertex of the free end.

Turning to Figure 19, another embodiment of an electrocautery probe 412, substantially similar to the first embodiment of the invention, is shown. The electrocautery probe 412 includes a roller bar electrode 422 having a central bore 442. The electrode 422 is preferably rotatably mounted on a bent axle portion 440 of the probe arm 423 extending through the central bore 442. The bent axle portion 440 has a Z-bend 441 which retains the electrode 422 on the bent axle portion, and an extended end 441a. The extended end 441a is relatively small in diameter but may be further sharpened to a point . The extended end 422 of the bent axle portion 440 may be used for spot coagulation and tissue sculpting.

Referring now to Figure 20, a cautery probe 1112 according to the second aspect of the invention has a full loop or circular electrode 1122 which is mounted between a pair of insulated arms 1123, 1125 such that substantially half of the electrode extends above a plane P defined by the axes al, a2 of the arms and substantially half of the electrode extends below the plane. The arms 1123, 1125 are joined at their proximal ends to an electrode lead 1127 and a resectoscope mounting sleeve 1129 is provided preferably at the location where the arms 1123, 1125 are joined to the electrode lead 1127. The electrode 1122 according to the invention is preferably made from a single piece of superalloy, stainless steel, tungsten, or copper which is soldered or welded to the distal ends of the arms 1123, 1125. An exemplary embodiment of the electrode is approximately 0.20 inches in diameter and fits into a STORZ Resectoscope using a 27 FR cannula. As will be described in more detail below, the exact morphology of the full loop electrode may be varied considerably according to the invention. The common feature of all of the embodiments of the invention is that the electrode 1122 has a lower working surface 1122a and an upper working surface 1122b. Moreover, the structure of the probe upon which the electrode is mounted may also be varied in several ways. For example, an alternative first embodiment of the full loop electrode utilizing a different type of probe is shown in Figure 21.

Referring now to Figure 21, a cautery probe 1212 according to the invention has a full loop electrode 1122 which is identical to the electrode described above. The difference between this embodiment and the embodiment described above is that the probe 1212 has only one arm 1223. The single arm 1223 is configured in the same manner as the arm 1123 described above and is coupled to an electrode lead 1227 and a resectoscope mounting sleeve 1229. This alternate embodiment combines the features of the present invention with features disclosed above with respect to the first aspect of the invention. In this embodiment, the lower working surface 1122a and the upper working surface 1122b of the electrode 1122 extend below and above an imaginary plane P' which includes the axis a'l of the single probe arm 1223 and the imaginary axis a' 2 of the missing probe arm.

As mentioned above, the morphology of the full loop electrodes according to the invention may be varied considerably. The electrode may have a conventional cylindrical wire profile, a broad band ribbon profile, a wedge profile, or a knife profile. Moreover, the full loop may have a composite of two or more profiles. Exemplary composite full loop electrodes are shown in Figures 22 through 24.

Turning now to Figure 22, a composite full loop electrode 1222 according to the invention has a lower portion 1222a with a cylindrical wire profile and an upper portion 1222b with a broad band ribbon profile. The lower portion of the electrode is useful for cutting and the upper portion is useful for coagulating. The electrode 1222 may be formed from a single piece of metal or may be formed from two pieces which are soldered or welded together at the points 1222c, 1222d. As shown, each portion 1222a, 1222b of the electrode 1222 occupies approximately 180° of the full loop. However, the upper and lower portions of the electrode need not occupy the same angular length. The electrode 1222 is coupled to the arms of a cautery probe in the same manner as the electrode 1122 described above.

Referring now to Figure 23, a composite full loop electrode 1322 according to the invention has a lower portion 1322a with a wedge profile, such as that disclosed in U.S. Patent #5,569,244, and an upper portion 1322b with a cylindrical wire profile. The lower portion of the electrode is useful for simultaneous cutting and coagulating and the upper portion is useful for cutting. The electrode 1322 may be formed from a single piece of metal or may be formed from two pieces which are soldered or welded together at the points 1322c, 1322d. As shown, each portion 1322a, 1322b of the electrode 1322 occupies approximately 180° of the full loop. However, the upper and lower portions of the electrode need not occupy the same angular length. The electrode 1322 is coupled to the arms of a cautery probe in the same manner as the electrode 1122 described above.

From the foregoing, those skilled in the art will appreciate that the composite full loop electrodes according to the invention may incorporate many different morphologies. Figure 24 shows yet another type of composite full loop electrode according to the invention. The electrode 1422 shown in Figure 24 has a lower loop 1422a and an upper knife 1422b. The electrode may be formed from a single piece of wire which is crimped to form the knife portion 1422b of the electrode. The electrode 1422 is coupled to the arms of a cautery probe in the same manner as the electrode 1122 described above.

In addition to providing full loop electrodes with different upper and lower morphologies, the invention provides a combined loop and roller electrode wherein a portion of a full loop electrode serves as the axle for a roller. Such an electrode according to the invention is shown in Figure 25.

Turning now to Figure 25, a composite roller and loop electrode 1522 according to the invention includes a wire full loop 1522a with a straight portion 1522b upon which a roller 1522c is mounted. The electrode 1522 is formed from a wire upon which the roller 1522c is mounted and which is then bent and then soldered or welded at some point 1522d in order to form a full loop. The electrode 1522 is coupled to the arms of a cautery probe in the same manner as the electrode 1122 described above . From the foregoing, those skilled in the art will appreciate that the features of the electrodes shown in Figures 22 through 25 may be combined in different ways and that the upper and lower working surfaces may be reversed. For example, a composite full loop electrode according to the invention may have an upper roller with a lower knife, an upper wedge with a lower ribbon, etc.

According to another aspect of the invention, a full loop electrode is bifurcated so that upper and lower working surfaces may be energized independently. Referring now to Figure 26, a cautery probe 1612 according to the invention has a bifurcated full loop electrode 1622 which is mounted between a pair of insulated arms 1623, 1625 such that substantially half of the electrode 1622b extends above a plane defined by the axes of the arms and substantially half of the electrode 1622a extends below the plane. The arms 1623, 1625 are mechanically joined at their proximal ends to an electrode lead stem 1627 and a resectoscope mounting sleeve 1629 is provided preferably at the location where the arms 1623, 1625 are joined to the electrode lead stem 1627. As shown in Figure 26, the lower portion 1622a of the electrode 1622 is electrically coupled to the arm 1623 and the upper portion 1622b of the electrode 1622 is electrically coupled to the arm 1625. Each arm is electrically coupled to a separate electrode lead 1627a, 1627b and the electrode leads are insulated from each other in the electrode lead stem. From the foregoing, it will be appreciated that the application of cautery current to the electrode lead 1627a will energize the lower portion 1622a of the electrode 1622 and that the application of cautery current to the electrode lead 1627b will energize the upper portion 1622b of the electrode 1622. It will further be appreciated that in order to take advantage of this cautery probe, a resectoscope may be modified to accommodate the two electrode leads 1627a, 1627b and to provide means for separately energizing the leads. While these modifications are not shown, those skilled in the art will understand how the resectoscope should be modified. The electrode 1622 enables the practitioner to set separate current settings for the upper and lower portions of the electrode as well as to selectively energize the upper and lower portions individually. As shown in Figure 26, the lower portion 1622a and the upper portion 1622b are physically separate pieces. However, it will be appreciated that these portions of the electrode 1622 may be physically coupled to each other with any non-conductive material such as a ceramic. Such physical coupling of the upper and lower portions of the electrode can add stability to the entire electrode and facilitate manufacturing of probes incorporating such an electrode.

There have been described and illustrated herein several embodiments of an electrocautery probe for use in a resectoscope. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while particular configurations have been disclosed with regard to electrodes for the electrocautery probe, it will be appreciated that electrodes otherwise shaped, sized, and oriented could be utilized with the single arm electrocautery probe of the invention. Also while particular dimensions have been disclosed, it will be appreciated that other dimensions could be utilized. Further, while curved electrodes have been shown, it will be recognized that polygonal electrodes could be used with similar results obtained. Moreover, while particular configurations have been disclosed in reference to welding and soldering, it will be appreciated that other configurations could be used as well. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as so claimed.

Claims

Claims :

1. An electrocautery probe for use in a resectoscope device having a scope with a longitudinal axis, and wherein a vertical plane and a first horizontal plane each extend through the longitudinal axis, said electrocautery probe comprising: a) exactly one conductive probe arm having proximal and distal portions; and b) an electrode having a first end attached to said distal portion of said probe arm, and a second unattached free end.

2. An electrocautery probe according to claim 1, wherein: said electrode includes a lowermost portion located between said first attached end and said second free end, said lowermost portion being aligned with the vertical plane.

3. An electrocautery probe according to claim 1, wherein: said electrode includes a lowermost portion and the distance from said first attached end to said lowermost portion is less than the distance from said second free end to said lowermost portion.

4. An electrocautery probe according to claim 1, wherein: said electrode includes a lowermost portion, said second free end is in a second horizontal plane, and said first attached end is in a third horizontal plane, such that said second horizontal plane is located between said lowermost portion and said third horizontal plane, wherein said second and third horizontal planes are each parallel to said first horizontal plane.

5. An electrocautery probe according to claim 4, wherein: said distance from said second horizontal plane to said third horizontal plane is approximately 0.10 inches.

6. An electrocautery probe according to claim 4, wherein: said second free end includes a pointed tip.

7. An electrocautery probe according to claim 1, wherein: said electrode is a loop electrode and said second free end includes one of a substantially pointed tip, a substantially rounded tip, and a substantially planar tip.

8. An electrocautery probe according to claim 7, wherein: said electrode includes a substantially planar tip having a surface which is inclined.

9. An electrocautery probe according to claim 8, wherein: said surface has a sharp edge.

10. An electrocautery probe according to claim 1, wherein: said electrode is adapted to vaporize in substantially three orthogonal planes.

11. An electrocautery probe for use in a resectoscope device having a scope with a longitudinal axis, and wherein a horizontal plane and a vertical plane each extend through the longitudinal axis, said electrocautery probe comprising: a) exactly one conductive probe arm having proximal and distal potions; b) axle means coupled to a distal portion of said probe arm; and c) a roller bar electrode having a central bore, a first end, a second end, a circumferential surface, said axle means extending through said central bore and said first end being adjacent said distal portion of said probe arm, wherein said circumferential surface and said second end are each adapted to perform at least one of resection and coagulation.

12. An electrocautery probe according to claim 11, wherein: said second end includes one of a substantially planar tip, a substantially rounded tip, and a substantially pointed tip.

13. An electrocautery probe according to claim 11, wherein: said axle means extends through said central bore beyond said second end and is adapted to perform at least one of tissue sculpting and spot coagulation.

14. An electrocautery probe according to claim 11, wherein: said axle means is a bent distal portion of said probe arm.

15. An electrocautery probe for use in a resectoscope device having a scope with a longitudinal axis, and wherein a horizontal plane and a vertical plane each extend through the longitudinal axis, said electrocautery probe comprising: a) exactly one conductive probe arm having proximal and distal portions, said probe arm situated such that said distal portion of said probe arm does not intersect the vertical plane; and b) an electrode coupled to said distal portion of said probe arm.

16. An electrocautery probe according to claim 15, wherein: said electrode is substantially centered relative to the vertical plane.

17. An electrocautery probe according to claim 15, wherein: said electrode includes a lateral midpoint, and the vertical plane intersects said lateral midpoint.

18. An electrocautery probe according to claim 15, wherein: said electrode is situated in a substantially orthogonal manner to vertical plane.

19. An electrocautery probe according to claim 15, wherein: said electrode is one of a loop electrode and a roller bar electrode.

20. An electrode for use in an electrocautery probe having at least one arm having a longitudinal axis and a distal end from which said electrode extends, said electrode comprising: a first portion which is adapted to extend above the longitudinal axis of the at least one arm and a second portion which is adapted to extend below the longitudinal axis of the at least one arm.

21. An electrode for use in an electrocautery probe having a pair of arms defining a plane and ends from which said electrode extends, said electrode comprising: a first portion which is adapted to extend above the plane and a second portion which is adapted to extend below the plane.

22. An electrocautery probe, comprising: a) a first conductive arm having a proximal end, a distal end, and a first longitudinal axis; b) an electrode lead coupled to said proximal end of said first conductive arm and extending proximally therefrom; and c) an electrode having a first portion which extends above said first longitudinal axis and a second portion which extends below said first longitudinal axis.

23. An electrocautery probe according to claim 22, further comprising: d) a second conductive arm having a proximal end, a distal end, and a second longitudinal axis, said first and second longitudinal axes defining a plane, wherein said first portion extends above said plane and said second portion extends below said plane.

24. An electrode or probe according to any of claims 20-23, wherein: said first portion and said second portion form a substantially contiguous loop.

25. An electrode or probe according to any of claims 20-24, wherein: said first portion and said second portion each have a different morphology.

26. An electrode or probe according to claim 25, wherein: said first portion has a morphology chosen from the group consisting of a wire loop, a wedge, a ribbon, a knife, and a roller, and said second portion has a morphology chosen from the group consisting of a wire loop, a wedge, a ribbon, a knife and a roller.

27. An electrode or probe according to any of claims 20-26, wherein: said first portion and said second portion are electrically insulated from each other and are each adapted to be separately energized.