Abstract: A method is provided for making an electrode tip for use in a bipolar electrosurgical instrument from a single flat blank of metal. The method uses a photo chemical machining process. The resultant electrode tip has a generally loop shaped working portion. Use of the flat blank of metal results in electrodes having working portions with sharp edges in cross-section. The working portions emit concentrated energy in the radial direction.

Abstract: A bipolar push rod assembly is disclosed in conjunction with an endoscopic bipolar cautery scissors instrument. The push rod assembly has two conductive push rods which are substantially covered and insulated from each other by a double lumen flexible sheath. The proximal ends of the push rods are stabilized by an overmolded plastic collar and the distal ends of the push rods are stabilized by a ceramic insulator. The plastic collar is provided with a snap retainer for coupling it to a plastic plug retainer having a pair of spaced apart passages. A pair of female plug adapters are press fit onto the proximal ends of the push rods and are maintained in place by the plug retainer with each adaptor residing in a respective one of the passages. The distal ends of the push rods are swaged approximately 90.degree. in opposite directions. A ceramic insulator is disclosed as a one-piece unit into which the distal ends of the push rods are inserted.

Abstract: A bipolar electrocautery valvulotome in the form of an elongated catheter having a longitudinal axis, a proximal end for being held and manipulated by a user, and a distal end. A first electrode is provided adjacent the distal end of a main body of the catheter and has an exposed surface facing distally of the catheter. The first electrode is electrically coupled to device for generating a current. A second electrode is disposed distally of the first electrode and is also electrically coupled to the current generating device. The second electrode has an exposed surface in a plane substantially perpendicular to the longitudinal axis of the catheter. At least one of the first and second electrodes is movable relative to the other so as to selectively capture a venous valve structure to be cauterized therebetween.

Abstract: A biological vessel harvesting device is provided which separates a segment of a biological vessel from adventitia surrounding the biological vessel while simultaneously cauterizing and sectioning tributaries extending from the separated vessel segment. The biological vessel harvesting device includes an outer catheter and a vessel grasping mechanism positioned within a lumen of the outer catheter for holding an end of a segment of the biological vessel to be harvested, the outer catheter being movable relative to the vessel grasping mechanism such that the vessel grasping mechanism and the vessel segment attached thereto can be drawn into the outer catheter lumen. The biological vessel harvesting device also includes a cautery-sectioning system positioned adjacent the outer catheter distal end in a ring around the outer catheter lumen.

Abstract: An electrode catheter for cardiac electrophysiology. An elongated body suitable for intravascular insertion surrounds a plurality of electrode lead wires. A composite electrode comprises a plurality of tip electrodes and defines a margin along a proximal edge. Each tip electrode is electrically connected to an associated electrode lead wire and is adjacent to another tip electrode on at least one side along an axis of the elongated body. Each tip electrode is separated from the another tip electrode by insulation. A cup electrode is electrically connected to an associated electrode lead wire and defines a cavity shaped to overlap the margin of the composite electrode. The cup electrode is fixedly secured to the composite electrode and to a distal end of the elongated body and is separated from the composite electrode by insulation.

Abstract: A coaxial electrosurgical instrument has an elongate inner electrode insulated from and contained coaxially within a hollow tubular elongate outer electrode, each electrode having a distal uninsulated end portion contactable simultaneously to tissue. A controlled, high-frequency, potential difference is provided between the electrodes so that an electrical current flows substantially only through contacted tissue which lies between the contacting portions of the inner and outer electrodes. An undamped voltage enables incision of the tissue. Cauterization and coagulation are performed by applying a periodically damped voltage. The outer electrode has an end surface of an uninsulated distal end portion to form a leading edge. An axially oriented cutout extends inwardly from the leading edge and accommodates a distal end portion of the insulating sleeve, permitting selective location of the inner and outer electrode surfaces contacting tissue during use.

Abstract: An electrosurgical instrument is provided for cauterization and/or welding of tissue of varying impedances, thicknesses and vascularity especially in the performance of endoscopic procedures. The instrument compresses the tissue between one pole of a bipolar energy source located on one interfacing surface, and a second interfacing surface. A second pole is located one of the two interfacing surfaces. In a preferred embodiment, the second pole is located on the same interfacing surface as the first pole and an insulator electrically isolates the two poles. A preferred application of the invention is in a cutting instrument wherein a hemostatic line is formed along a cut line using RF energy.

Abstract: An electrode for vaporizing tissue is disclosed which has a head provided with projections and recesses and which is supported by at least one externally insulated electrically conducting branch. In order to provide a better and more effective electrode with regard to vaporization power and which can be easily cleaned and cheaply manufactured, the head which is rigidly fixed to the branch comprises essentially of part of a rotationally symmetrical body.

Abstract: A volumetric tissue ablation apparatus includes a probe having a plurality of wires journaled through a catheter with a proximal end connected to the active terminal of a generator and a distal end projecting from a distal end of the catheter. The probe wire distal ends are arranged in an array with the distal ends located generally radially and uniformly spaced apart from the catheter distal end. A conductor connected to the return terminal of the generator is located relative to the probe wire array to form a closed electrical circuit through tissue to be ablated. Preferably, the probe wire array includes 10 wires, each formed in an arch from the catheter distal end. The conductor can be either a conventional ground plate upon which the tissue is supported, or a conductor wire extending through the probe and electrically insulated from the probe wires.

Abstract: An insulated surgical scissors, having a monopolar or a bipolar scissors construction, that can be used during laparoscopic, endoscopic and open surgery for cutting and coagulating tissue.

Abstract: Query electrodes are provided for monitoring the electrical impedance of tissue as it is treated with electrosurgical energy. In one embodiment, based on a predicted model of tissue impedance and a number of initial impedance readings, the impedance at which tissue treatment is completed is predicted. More particularly, a minimum impedance level is measured and a function of the minimum impedance is used to determine impedance at which coagulation is completed. A control device is provided for bringing the output of the generator within an optimum range based on a system load curve. In one embodiment the impedance monitoring device is used in conjunction with a bipolar electrosurgical instrument. Preferably, the instrument comprises electrically opposite therapeutic electrodes, each located on one or more tissue engaging surfaces for engaging tissue to be treated, and electrically opposite query electrodes, located on one or more tissue engaging surfaces.

Abstract: A bipolar electrosurgical device includes electrodes that are part of a tip which removable from a handle. The electrodes are configured for connection to electrical contacts when the tip is attached to the handle, and disconnected from the contacts which the tip is detached. The electrodes are mounted on a housing of the tip so that the proximal ends of the electrodes are spaced from each other. The handle has an opening which receives the housing, and a plurality of contacts disposed for connection to the proximal ends of the electrodes when the housing is inserted into the opening. Because the electrodes themselves provide the connection with the electrical components of the handle, there is no need for a separate electrical connector. The tip and the electrodes are economically disposable after, e.g., a single use, while the handle can be reused in multiple surgical procedures with other tips. An inventory of differently-constructed tips (e.g.

Abstract: An apparatus for closing and sealing a vascular puncture is connected to an energy supply such that heat is generated in, or thermally conducted to, the tissue, thereby thermally fusing the vascular tissue together. The method for closing and sealing a vascular puncture comprises applying radio frequency or other energy to the tissue, the energy being sufficient to thermally fuse the tissue together, thus sealing the puncture. Embodiments of depth finding and guiding devices, as well as blood vessel occluders, are also disclosed.

Abstract: An improved electro surgical instrument is provided for cauterization and/or welding of tissue of varying impedances, thicknesses and vascularity especially in the performance of endoscopic procedures. The instrument compresses the tissue between one pole of a bipolar energy source located on one interfacing surface, and a second interfacing surface. A second pole is located on one of the two interfacing surfaces. In a preferred embodiment, the second pole is located on the same interfacing surface as the first pole and an insulator electrically isolates the two poles. A preferred application of the invention is in a cutting instrument wherein a hemostatic line is formed along a cut line using RF energy.

Abstract: A cordless electrocautery unit for use in surgical procedures is described in which the unit is battery operated and therefore cordless. The unit is microprocessor controlled and provides for automatic feedback and control of the output power, in accordance with one of multiple power levels selected by the user.

Abstract: An RF ablation apparatus has a delivery catheter with a delivery catheter lumen and a delivery catheter distal end. A first RF electrode is positioned in the delivery catheter lumen. The first RF electrode has a distal end, RF conductive surface, and a lumen. A second RF electrode has a distal end. The second RF electrode is at least partially positioned in the lumen of the first catheter, with its distal end positioned at the exterior of the first RF electrode distal end. Additionally, the second RF electrode distal end has a geometry that permits it to be substantially a groundpad. The distal end of the first RF electrode is moved in a direction away from the second RF electrode distal end to create a painting effect of an ablation band or line between the two distal ends. Alternatively, the distal end of the second RF electrode can be moved in a direction away from the distal end of the first RF electrode.

Abstract: An improved lead extraction system having multiple-jaw cutting edge that is useful for extraction and removal of unwanted lead by a minimal invasive procedure. A lead extraction system suitable for radiofrequency ablation of scar tissues surrounding the implanted lead comprises a catheter sheath having a distal end, a proximal end and at least one lumen extending therebetween, wherein a locking stylet is provided. In one embodiment, the lead extraction system has fluid infusion and irrigation means at its distal tip section and a set of ablation electrodes for loosening the target tissue by applying radiofrequency energy and cooled fluid to said electrode and its contacted tissue.

Abstract: Endoscopic bipolar scissor blades are formed in a laminate assembly of an outer electrically conductive layer, an intermediate electrically insulating layer, and an inner face layer which is a coating of titanium dioxide, chromium dioxide, or zirconium dioxide. In one embodiment, the conductive layer is a metal blade, while the insulating material is a ceramic which is fixed to the metal blade. In a second preferred embodiment, the insulating layer and the inner face layer are applied simultaneously by coating the metal blade with a mixture of ceramic and titanium dioxide, chromium dioxide, or zirconium dioxide. In a third embodiment, the insulating layer is a molded ceramic blade, and the electrically conductive layer is metalized or otherwise fixed to the ceramic blade. In all embodiments, the cutting edges and shearing surfaces are insulated from the electrodes, and no short circuit can form between the electrodes even though the cutting edges and shearing surfaces are metal.

Abstract: A clamping force mechanism for use with electrosurgery allow a user to seal and/or join patient's particular vascular tissue; the mechanism is elongate with user and patient ends. An actuator is at the user end and the effectors are at the patient end. Each effector has a face of an area to contact the particular vascular tissue. A lost motion connection transfers user actuation to the effectors to hold a predetermined clamping force during electrosurgical tissue sealing. A yielding member in the loss motion connection clamps the particular tissue between the faces with a predetermined force. The yielding member is a spring, slip clutch or hydraulic coupling possibly near the actuator. An active electrode is carried on one end effector and a return electrode contacts the tissue so an electrosurgical energy supply connected thereacross delivers energy therebetween. A feedback circuit responds to parameters of energy delivered to tissue.

Abstract: This invention is a device and procedure for the correction of optical abnormalities in a human eye. It involves use of an inventive electrosurgical energy probe with specific physical configurations. The process preferably utilizes a high frequency RF electro-desiccation or ablation device. The procedure involves the initial step of forming at least one access site allowing access to the corneal volume behind the Bowman's Layer. It preferably is placed in the anterior surface of the cornea through and ending posterior to the Bowman's layer of the eye. The electrosurgical probe is then introduced into the access site and, depending upon the visual abnormality to be corrected, the probe is activated to adjust the volume of the corneal stromal layers through ablation or desiccation. The shape of the volume desiccated or ablated is dependent upon the aberration to be corrected.

Abstract: A roller (20) for an electrocautery probe or electrode (30), such as of the type used with a resectoscope. The roller (20) generally has a conductive body with an axis of rotation (26) and a surface with a circular cross-section in a plane perpendicular to the axis of rotation (26). The roller (20) further includes surface features (22) for generating circular-shaped areas of focused current concentration (24) in a radial direction relative to the axis of rotation (26) of the roller (20). For this purpose, recesses can be formed in the surface of the roller (20), with each recess defining a circular-shaped edge at the roller surface. Examples of suitable recesses include cylindrically-shaped perforations and concave impressions in the surface of the roller (20).

Abstract: A thermokeratoplasty system and method for locally heating and reshaping a cornea in a manner that produces a minimal regression of the corneal correction. The system includes a probe that is coupled to a power source which can provide a predetermined power, frequency and time duration that creates a thermal profile within the cornea which extends from the epithelium into the corneal stroma. The electrical return of the probe is a lid speculum which maintains the eye lids in an open position. The probe is placed into contact with the cornea and energy is transferred from the power source to the eye, through the lid speculum and back to the power source. The energy from the power supply is focused by a probe tip that locally heats and denatures the cornea, and causes a subsequent shrinkage of corneal tissue. A pattern of denatured areas can be created around the cornea to correct the vision of the eye. It has been found that power no greater than 1.2 watts, for a duration no greater than 1.

Abstract: A bipolar coagulation forceps 1 with a connection 2 for high frequency energy and two forceps limbs 4 capable of being pressed together against a spring tension is so constructed that a rinsing tube can be provided in a simple manner and without impinging on the space between the forceps limbs 4. For this purpose, the forceps limbs 4 comprise grips 5 which can be pushed together against spring tension with working limbs 6 subsequently fastened on them, whereby then at least one of the working limbs 6 has a hollow cross section or is constructed as a tube and has a connection 7 for the rinsing fluid, so that guidance parts 11 can be arranged between the grips 5 for the reciprocal guidance of the working tips 3 of the forceps 1. The working limbs 6 are for this reason arranged on parallel narrow sides 8 of the grips 5, that is lateral to the grip areas, where the guiding parts 11 are accommodated.

Abstract: An surgical stapling instrument is provided which uses a thermogenic energy preferably bipolar radiofrequency energy for cauterization and/or welding tissue. The instrument compresses tissue between one pole of a bipolar energy sources contained on a first interfacing surface and a second pole of a bipolar energy source contained on a second interfacing surface. Staples and thermogenic energy are applied to the compressed tissue. In a preferred embodiment a cutting element for cutting tissue is incorporated into the instrument.

Abstract: An electrode tip is provided for use in a bi polar electrosurgical instrument. The electrode tip has a generally loop shaped working portion, including a first and second electrode, The first electrode is generally loop shaped. The second electrode generally surrounds the first electrode and is generally spaced from and coplanar with the first electrode. The electrodes have sharp edges in cross-section which emit concentrated energy in the radial direction.

Abstract: An apparatus and method for cauterizing small vessels through small incisions or puncture openings is described. The apparatus is comprised of a pair of elongate electrodes capable of being inserted into a hollow needle. In a preferred embodiment, the elongate electrodes are disposed within a tube that is slidable in a longitudinal direction between a proximal position, in which the tube releases the electrodes into an outwardly biased position, and a distal position in which the electrodes are enclosed by the tube. The device is introduced into a body cavity with the tube in the distal position. The tube is then moved to its proximal position to release the electrodes, and a vessel is grasped using hooks at the electrode tips. A different electrical polarity is applied to each electrode, causing current to pass through the vessel from one electrode to the other to cauterize the vessel.

Abstract: An impedance feedback electrosurgical system is useful with electrosurgical tools to maintain a substantially constant level of current within the tissue in contact with the tool. The system comprises active and return electrodes associated with an electrosurgical tool, an impedance monitoring device and a power control unit. Energy sufficient to affect tissue is delivered through the active electrode to tissue and to the return electrode. The impedance measuring device is in circuit with the return electrodes and measures the impedance of tissue. A signal representative of tissue impedance is communicated from the impedance measuring device to the power control unit. The power control unit adjusts the energy applied to tissue to maintain tissue impedance within a preselected and desired range.

Abstract: An electrosurgical instrument is provided for cauterization and/or welding of tissue of varying impedances, thicknesses and vascularity especially in the performance of endoscopic procedures. The instrument compresses the tissue in the compression zone between first interfacing surface and second interfacing surfaces. The compression zone is formed by an insulator which forms a compression ridge in one of the interfacing surfaces and separates first and second electrically opposite electrodes. A preferred application of the invention is in a cutting instrument wherein a hemostatic line is formed using RF along a cut line.

Abstract: A bipolar electrosurgical instrument having a handle, an end effector and an elongated hollow tube. The handle includes first and second grip members. The end effector includes first, second and third electrodes. The first electrode is substantially triangular in shape. The first electrode is adapted to pivot between an open position and a closed position. The first electrode also pivots around its proximal to distal axis and includes a coagulating surface and a cutting edge. The second and third electrodes are arranged substantially parallel to the first electrode when the first electrode is in the closed position. The elongated hollow tube includes a mechanism connecting the handle to the end effector such that movement of the first and second grip members relative to one another causes the first electrode to move relative to the second and third electrodes.

Abstract: A bipolar electrosurgical scissors adapted to electrically cauterize and desiccate organic tissue prior to cutting the tissue in order to reduce or prevent bleeding. The bipolar electrosurgical scissors include a pair of scissor members attached through an electrically insulating point. Each scissor member includes, at a distal end, a shearing surface with a plurality of electrode regions interspersed between a plurality of insulating regions. The insulator regions are offset such that upon closure of the shearing members, the insulation region of one shearing member opposes a corresponding electrode on the other shearing member.

Abstract: A flexible bipolar electrode for neurosurgery includes an inner hypotube defining an irrigation passageway and a hollow outer electrode surrounding the hypotube, with the outer electrode and hypotube together establishing a bipolar electrode. An empty void is established between the electrodes to facilitate flexibility of the bipolar electrode when, for example, the electrode is advanced through a curved lumen of a neuroendoscopy instrument.

Abstract: An electrosurgical instrument is provided for cauterization and/or welding of tissue of varying impedance, thickness, compressibility, density, vascularity, etc., especially in the performance of endoscopic procedures. The instrument provides two electrodes of different electrical potentials. One electrode is moveable with respect to the other electrode to vary the distances between the electrodes and thus the impedance of the tissue as presented to the generator. The electrode distances may be varied by an automated or user controlled device.

Abstract: An adaptor cable and methods are provided for use with electrosurgical bipolar instruments and standard commercially available electrosurgical generators that reduce arcing. The adaptor cable limits the peak-to-peak voltage developed between the electrodes of the electrosurgical instrument by providing a minimum load impedance between the output terminals of the electrosurgical generator.

Abstract: As electrosurgical instrument that has characteristics especially attractive in performing bipolar electrosurgery. It is believed that the relatively high current densities typically employed in using bipolar instruments result in very high incidents of sticking and other undesired characteristics when such instruments are coated with conventional coatings. A nickel-free high chromium content composite coating that manifests undesired characteristics when employed with monopolar electrosurgical implements has unexpectedly been discovered to embody very desirable characteristics when employed with bipolar instruments and is therefore efficaciously employed as a coating on bipolar implements.

Abstract: An electrosurgical instrument is provided for cauterization and/or welding of tissue of varying impedances, thicknesses and vascularity especially in the performance of endoscopic procedures. The instrument compresses the tissue between an electrode associated with a first pole of a bipolar energy source located on one interfacing surface off a first element, and a second interfacing surface of a second element. The first and second elements are used to engage and compress tissue between the first and second interfacing surfaces. A second electrode associated with a second pole is located one of the two interfacing surfaces. The first electrode is either recessed into the first tissue contacting surface and/or offset from the second electrode on the same or opposing surfaces. A preferred application of the invention is in a cutting instrument wherein a hemostatic line is formed along a cut line using RF energy.

Abstract: An endoscopic bipolar multiple sample bioptome includes a relatively long conductive flexible member having a lumen with an axially displaceable conductive wire extending therethrough and covered with an electrically insulating sheath. The proximal ends of the flexible member and wire are coupled to a manual actuation device for axially displacing one of the flexible member and wire relative to the other and the manual actuation device is provided with bipolar electrical couplings for electrically coupling one pole of a current source to the flexible member and the other pole of the current source to the wire. The distal end of the flexible member is mechanically and electrically coupled to a partially conductive cylinder having a distal edge and the distal end of the wire is mechanically and electrically coupled to the jaw assembly. The jaw assembly includes a pair of opposed toothed jaw cups each of which is coupled by a narrow resilient arm to a base member.

Abstract: An electrosurgical hemostatic instrument is provided in which the coagulation status of tissue engaged by two elements delivering an electrosurgical energy to tissue may be observed, and in which damage from thermal spread may be minimized. A preferred embodiment of the invention provides a bipolar endoscopic clamping, coagulation and cutting device. In this device, the outer conductive surface of the tissue engaging elements includes openings therethrough. The openings are adapted to allow an observer to see the tissue as it is being treated, coagulation may be observed by watching the region through the openings. In addition, the inclusion of openings in the end effector enhances coagulation from speed by reducing the thermal mass of the end effector without substantially reducing the structural strength of the end effector jaws. Finally, the openings may be used to observe the motion of the knife as it moves through the end effector.

Abstract: A bipolar electrosurgical scissors has an improved coagulation capability. Both poles of electrosurgical energy are exposed on the exterior surfaces of each shearing member so that the scissors can be used to coagulate tissue using only one shearing member. There may be two or more electrically conductive regions on the exterior surface of each shearing member. The conductive regions may be formed by laminating, depositing, or inlaying electrically conductive material on the exterior surfaces. The conductive regions are electrically insulated from each other. In one embodiment, the shearing surfaces are also electrically conductive and are each connected to the same electrical pole. In another embodiment, the conductive material that forms one of the conductive regions on each exterior surface also extends through the shearing member to also form a conductive shearing surface.

Abstract: In electrosurgical apparatus for tissue desiccation and cutting, an electrosurgical generator has a series-connected output inductor which forms a series resonant circuit with the capacitance of the generator load, the load including an electrode unit and a cable coupled to the generator output. The series resonant frequency is typically 1.5 f where f is the operating frequency of the generator. A capacitor may be included, coupled between the conductors which connect bipolar electrodes to the generator, to increase the load capacitance. The effect of these measures is to boost the output voltage available for electrosurgical treatment, especially for tissue cutting.

Abstract: A bipolar electrosurgical instrument including four shearing members is disclosed. The shearing members are movable to an open position for grasping tissue, a closed position for desiccating tissue by application of electrical current and a cutting position for shearing tissue. The electrical current may be applied in an X-shaped pattern to thereby localize desiccation to the maximum extent possible. A method of using the bipolar electrosurgical instrument is also disclosed.

Abstract: An electrosurgical device for the resolution of an occlusive deposit within a lumen of the body, and a method of using such a device. The device has a distal end that is insertable within and along the lumen to a desired position with respect to the occlusive deposit. The distal end of the device includes a number of electrodes that are spaced about the device. The electrodes may be individually supplied with current, so that the location of resolution is controlled within the lumen.

Abstract: A RF valvulotome and method of use is described. The valvulotome comprises an elongated, flexible polymeric tube or rod supporting a pair of paddle members at its distal end, the paddle members defining opposed facing surfaces having a gap therebetween. A pattern of metallization, comprising electrodes, are formed on the opposed facing surfaces and means are provided for applying RF energy between the electrodes after the instrument has been introduced into a vein and advanced to the point where the cusp of a vein valve is disposed in the gap. In a preferred embodiment, the paddles are movable toward and away from the center of the instrument and may incorporate a flushing lumen through which saline may be injected for effecting valve closure and facilitating placement of the paddle members within the pockets defining the valve. An optical-fiber bundle may also be passed through the lumen of the instrument to facilitate viewing of the internal vein structure as the catheter is being advanced.

Abstract: Pre-shaped cardiac catheters for mapping and selective ablation of a portion of cardiac circuitry includes a preshaped first curved portion for positioning around the ostium of coronary sinus and a second curved portion for maintaining the first curved portion in its desired position. The method involves introducing a catheter assembly, including a guide-wire and a preshaped catheter, to a location proximal the atrium. As the guide-wire is withdrawn from within the catheter, the catheter assumes its preshaped form at the target location. Alternatively, a catheter assembly, with or without a guide-wire, may be introduced to the target ablation site via a catheter sheath. The catheter includes an array of spaced apart electrodes on at least a portion of the catheter. Each electrode may be activated remotely to a preselected current level for a preselected time interval to ablate a target portion of cardiac circuitry adjacent the electrodes.

Abstract: A double acting bipolar endoscopic scissors includes a hollow tube with an integral clevis and a bipolar push rod extending therethrough. The tube is rotatably mounted in a handle member which is provided with a manual actuation lever. The bipolar push rod includes a pair of spaced apart rods which are insulated along substantially their entire lengths by polypropylene sheaths, and which are insert molded in a distal insulating collar near their distal ends, in a proximal insulating collar near their proximal ends, and in a plurality of non-conductive cylinders therebetween. The distal collar includes a flattened distal portion and the distal ends of the rods are bent approximately 90 degrees and exit the flattened portion. A pair of scissor blades are mounted in the clevis with an axle screw and a nut and are insulated from the clevis and the axle screw. One of the scissor blades has a ceramic coating on its face to insulate it from the other scissor blade.

Abstract: An impedance monitoring device is provided for monitoring the electrical impedance of tissue as it is treated with electrosurgical energy. Based on a predicted model of tissue impedance and a number of initial impedance readings, the impedance at which tissue treatment is completed is predicted. More particularly, a minimum impedance level is measured and a function of the minimum impedance is used to determine impedance at which coagulation is completed. A control device is provided for bringing the output of the generator within an optimum range based on a system load curve. In one embodiment the impedance monitoring device is used in conjunction with a bipolar electrosurgical instrument. Preferably, the instrument comprises electrically opposite electrodes located on one or more tissue engaging surfaces for engaging tissue to be treated.

Abstract: A coaxial electrosurgical instrument has an elongate inner electrode insulated from and contained coaxially within a hollow tubular elongate outer electrode. Both electrodes have respective distal end portions which are uninsulated and contactable simultaneously to tissue to be operated on. A controlled, high-frequency, potential difference is provided between the electrodes under the user's control when the uninsulated distal end portions thereof are simultaneously contacted to tissue. A high frequency, high density, electrical current is thus caused to flow substantially only through that part of the contacted tissue which lies between the contacting portions of the inner and outer electrodes. Tissue is readily and cleanly cut between the inner and outer electrodes applying a continuous, undamped high frequency voltage difference.

Abstract: An electro-surgical radio-frequency instrument is described for the coagulating and/or cutting of tissue with a shaft having a radio-frequency voltage connection. A working tip is arranged at the distal end of the shaft and has two electrodes which are connected or connectable to a radio-frequency voltage connection. The working tip is shaped as a hook or a spatula and comprises the two electrodes which are arranged next to one another, and an insulation layer which is arranged between them and which is connected to the electrodes so as to form a unit.

Abstract: A high-frequency cauterizing apparatus comprises a high-frequency power supply device, having a plurality of high-frequency output modes, for generating a high-frequency current, at least one medical treatment instrument to be connected to the high-frequency power supply device, a detector for detecting connection of the medical treatment instrument to the high-frequency power supply device, a control signal generator for identifying the type of the medical treatment instrument on the basis of a detection signal from the detector and generating a control signal, and a controller for controlling a high-frequency output from the high-frequency power supply device on the basis of the control signal generated from the control signal generator.

Abstract: A bipolar electrosurgical scissors for use in open or endoscopic surgery has a pair of opposed metal blade members pivotally joined to one another and to the distal end of the scissors itself by a rivet. Each of the blade members comprises a cutting blade having an electrode on the non-shearing surface. An intermediate insulative coating is disposed between each cutting blade and its associated electrode coating. The cutting blade is preferably fabricated from metal such as stainless steel and the electrode coating comprises metal traces deposited thereon through a mask to yield a desired pattern extending along but separated from the blade's cutting edge. Cutting is performed, steel-on-steel, without causing a short circuit between the blades which themselves may function as one of the bipolar electrodes.

Abstract: An integrated catheter assembly for enabling diverse in situ therapies includes a catheter with an irrigation fluid lumen, a distal tip portion that acts as a hemostat and a needle for injection therapy that extends through the catheter lumen and a lumen in the distal tip portion. A needle hub structure carries the catheter and provides a sealing entrance for a needle that can be displaced between extended and retracted positions. The needle and electrodes are electrically isolated. The apparatus provides a physician the options of irrigating tissue, cauterizing tissue or injecting tissue without the need for removing the apparatus from the working channel of an endoscope.