United States Patent
`Stem et al.
`
`[19]
`
`[54]
`
`[75]
`
`COAGULATING FORCEPS
`
`Inventors: Roger A. Stern, Cupertino, Calif.;
`Richard M. Soderstrom, Seattle,
`Wash.; Vincent N. Sullivan; Robert L.
`Marion, both of San Jose, Calif.
`
`Assignee:
`
`Vesta Medical, Inc., Mountain View,
`Calif.
`
`Appl. No.:
`Filed:
`
`106,601
`Aug. 16, 1993
`
`Related U.S. Application Data
`Continuation-in—part of Ser. No. 877,567, May 1, 1992,
`Pat. No. 5,277,201, and Ser. No. 46,683, Apr. 14, 1992.
`Int. Cl.5 .............................................. A61B 17/39
`U.S. Cl. ......................................... 606/51; 606/52
`Field of Search ..................... .. 606/41, 42, 45, 46,
`606/48-52
`
`References Cited
`U.S. PATENT DOCUMENTS
`4,655,216 4/ 1987 Tischer .....
`.. .... .... .. ..... 606/51
`5,122,137
`6/1992 Lennox
`. 606/49 X
`5,190,541
`3/1993 Abele et al.
`. 606/48 X
`5,277,201
`1/1994 Stem ..................................... 606/41
`
`FOREIGN PATENT DOCUMENTS
`2573301
`5/1986 France .................................. 606/52
`
`llllllllllllllIllIllll||l||I||||llllllllllllllllllllIllllllllllllllllllllll
`US005443463A
`
`[11]
`
`[45]
`
`Patent Number:
`
`Date of Patent:
`
`5,443,453
`
`Aug. 22, 1995
`
`OTHER PUBLICATIONS
`
`Sugita et al., “Bipolar coagulator . . . thermocontrol", J.
`Neurosurg., vol. 41, Dec. 1974, pp. 777-779.
`Primary Examiner-—-Lee S. Cohen
`Attorney, Agent, or Firm—Oblon, Spivak, McCle1land,
`Maier & Neustadt
`
`[57]
`
`ABSTRACT
`
`A method and an apparatus for selectively coagulating
`blood vessels or tissue containing blood vessels involves
`the placement of the blood vessels or tissue containing
`blood vessels between the prongs of a forceps with the
`jaws of the forceps containing a plurality of electrodes
`which are energized by radio-frequency power. A plu-
`rality of sensors are associated with the electrodes and
`in contact with the vessels or tissue in order to measure
`the temperature rise of the tissue or blood vessels and to
`provide a feedback to the radio—frequency power in
`order to control the heating to perform coagulation of
`the vessels or tissue. In a further development,
`the
`upper prong of the device is split into two parts with a
`cutting blade between the two upper parts in order to
`provide for cutting of the coagulated vessels subsequent
`to the coagulation. The cutting may be accomplished
`either mechanically or with an electrosurgical cutting
`device.
`
`6 Claims, 5 Drawing Sheets
`
`ETHICON ENDO-SURGERY, INC.
`
`EX. 1015
`
`1
`
`

`
`U.S. Patent
`
`Aug. 22, 1995
`
`5,443,463
`
`SOURCE
`
`CONTROLLER
`
`ELECTRO SUHRGICAL
`POWER SUPPLY
`
`SOURCE
`
`CONTROLLER
`
`2
`
`

`
`U.S. Patent
`
`Aug. 22, 1995
`
`Sheet 2 of 5
`
`5,443,463
`
`ELECTRO SURGICAL
`POWER SUPPLY
`
`SOURCE
`CONTROLLER
`
`3
`
`

`
`U.S. Patent
`
`Sheet 3 of 5
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`
`U.S. Patent
`
`Sheet 4 of 5
`
`5,443,463
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`
`U.S. Patent
`
`Aug. 22, 1995
`
`Sheet 5 of 5
`
`5,443,463
`
`6
`
`

`
`5,443,463
`
`1
`
`COAGULATING FORCEPS
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`l0
`
`15
`
`20
`
`This is a continuation-in-part of application Ser. No.
`07/877,567,
`filed May 1, 1992, now U.S. Pat. No.
`5,277,201 and Ser. No. 08/046,683, filed Apr. 14, 1993.
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`The present invention relates to a method and an
`apparatus for an electrosurgical coagulation and cutting
`of regions of tissue or blood vessels over relatively large
`areas with temperature control.
`2. Discussion of the Background
`Surgical procedures and particularly electrosurgical
`procedures often require the complete cutoff of large
`regions of tissue, or the complete cutoff of the blood
`supply through a main artery before such surgery can
`be performed. A typical example is the requirement that
`the uterine artery be closed off before the uterus can be
`removed during a hysterectomy. The cutting off of the
`blood supply through the artery is accomplished by
`suture ligation, staples or clips or electrosurgical desic-
`cation. Obviously, for large arteries, suture ligation is a
`difficult and long procedure which increases the time
`required for anesthesia resulting in an opportunity for
`complicating factors to arise. Aside from an increase in
`the length of time, there is an obvious increase in the
`expense of the procedure. Furthermore, when such
`arteries or vessels require their blood supply to be cut
`off during an emergency surgery, the amount of time to
`control the bleeding from the large vessel is more than
`just an expense or a complicating factor: it is a life— 35
`threatening period of time required before the actual
`surgery may be accomplished. Obviously, there is a
`need for an improved method for ligation and the cut-
`ting off of larger vessels.
`Although the above example addresses the cutting off 40
`of a main artery, in many instances the blood supply
`needs to be cutoff to large regions of tissue containing
`many blood vessels and also in many instances the cut-
`ting off of the blood supply to these tissues is all that is
`required. In other words, in many applications, what is
`required is only the stopping of blood supply to a region
`of tissue containing many blood vessels.
`In a similar manner, when cutting through large re-
`gions of tissue containing blood vessels, considerable
`time is expended ligating the individual blood vessels
`into tissue. There is a need for an improved method of
`cutting coagulating of such type of large regions of
`tissue.
`
`25
`
`30
`
`50
`
`One of the approaches in the electrosurgical proce-
`dure to reliably seal off large areas is the utilization of a
`device which can accomplish the cutoff of the blood
`supply through the main artery or a plurality of smaller
`vessels. Current electrosurgical devices face severe
`problems which either make their use inconvenient or
`severely limit their application or, in certain instances,
`entirely rule out the use of such electrosurgical devices.
`Prior art devices are inherently difficult to use over a
`large area or an extended linear region because it is
`difficult with current electrosurgical devices to produce
`coagulated tissue over such a large area or over such a
`long linear region. Furthermore, it is extremely difficult
`to know the degree of completion of coagulation be-
`cause there is no feedback mechanism to determine
`
`55
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`60
`
`65
`
`2
`when the coagulation is complete. Therefore, with the
`present electrosurgical devices it is entirely possible that
`the application of the device will have been stopped
`before completion of coagulation resulting in continued
`bleeding. It is equally possible that the device was ap-
`plied for too long a time which, at best, is a waste of
`time and, at worst, could have caused other damage to
`adjacent tissue or could have burned the tissue intended
`to be coagulated, resulting in compromised sealing of
`tissue and the risk of continued bleeding.
`Yet another difficulty with the present electrosurgi-
`cal devices available for coagulation is the requirement
`for the use of multiple devices. That is, once coagula-
`tion has been completed, another device is necessary to
`cut the tissue.
`
`Uniform coagulation over large areas of tissue using
`standard electrosurgical techniques is extremely diffi-
`cult to achieve. This difficulty is due in part to the fact
`that it is not known how to determine the proper rate at
`which to apply energy or how to determine when the
`desired amount of coagulation has been achieved. If the
`energy is applied too rapidly, the superficial layers of
`tissue may desiccate too quickly and insulate the deeper
`tissues from further application of electrosurgical en-
`ergy. If insufficient energy has been applied, the desired
`depth of penetration of the electrosurgical energy may
`never be achieved. The only feedback currently avail-
`able to an operator of the prior art electrosurgical de-
`vices is the visible inspection of the surface of the tissue
`which is being coagulated or monitoring of the level of
`RF current. Surface inspection is no indication of any
`effect achieved in deeper layers of tissue. Similarly, a
`drop in RF current does not differentiate between the
`formation of an insulating superficial layer as complete
`desiccation. Thus,
`the application of electrosurgical
`procedures to cut off blood supply is a developed skill
`based upon experience which either requires separate
`training in this field or a stop-and—inspect procedure
`with even such procedure failing when the energy is
`applied too quickly because the deeper tissues may have
`become insulated from further heat application.
`There thus exists a long-felt need for a rapid, efficient,
`safe and sure method and device for completely cutting
`off the blood supply through an artery for vessel and
`the subsequent cutting of the artery or vessel in order to
`prepare for a further surgical procedure.
`A similar need exists for an efficient, safe and sure
`method and device for sealing or coagulating large
`areas of vascular tissue such as mesentery, bowel, meso-
`appendix, lung, fat tissue, lymph nodes, fallopian tubes,
`pedicles and the like.
`
`SUMMARY OF THE INVENTION
`
`Accordingly, one object of the present invention is to
`provide a novel apparatus and method for performing
`safe and rapid blood supply cutoff through an artery, a
`vessel, or other tissue in an efficient and sure manner
`without the need for visual inspection.
`It is a further object of the present invention to pro-
`vide a generic line of electrosurgical tools capable of
`supplying temperature-controlled electrosurgical en-
`ergy over large areas.
`It is also an object of the present invention to provide
`a single device which allows for both stoppage of blood
`supply and the cutting of the artery itself subsequent to
`stoppage of the blood supply.
`
`7
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`5
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`10
`
`3
`These and other objects are accomplished by using a
`plurality of area electrodes and the individually control-
`ling the energy delivered to each electrode by means of
`a switchable temperature feedback circuit.
`It is a further object to provide a feedback means for
`monitoring temperature, impedance and power to pro-
`vide a control algorithm for operation of the device.
`The objects of the present invention are provided by
`way of a forceps including split jaws and having a plu-
`rality of electrodes as well as a plurality of temperature
`sensors wherein operation of the device is accomplished
`by a scissors-like movement of the forceps.
`It is a further object of the present invention to pro-
`vide a structure whereby the split jaws of the coagulat-
`ing forceps have an intermediate cutting blade com-
`bined with said forceps in order to sever the ligated
`vessel in the center of a coagulated area.
`It is a further object of the present invention to pro-
`vide a coagulating forceps with electrosurgical genera-
`tion energy applied through a switching circuit.
`It is a further object of the present invention to pro-
`vide bipolar delivery of energy to the coagulating for-
`ceps.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`A more complete appreciation of the invention and
`many of the attendant advantages thereof will be
`readily obtained as the same becomes better understood
`by reference to the following detailed description when
`considered in connection with the accompanying draw-
`ings, wherein:
`FIGS. 1A and 1B show a general view of a coagulat-
`ing forceps according to the present invention, with
`FIG. 1B showing a close-up view of a compressed ves-
`sel being clamped by the forceps;
`FIGS. 2A, 2B and 2C show a construction variation
`with FIG. 2A illustrating the clamping of a vessel by a
`forceps having split upper and lower jaws, FIG. 2B
`showing the addition of a cutting blade to a split upper
`jaw and FIG. 2C illustrating a side position cutting
`blade for a single pair of upper and lower jaws;
`FIG. 3 illustrates a schematic structure for a power
`source controller system;
`FIG. 4 is an illustration of a schematic of a monopolar
`construction of the power delivery system;
`FIG. 5 is a schematic of a bipolar/monopolar con-
`struction of the power delivery system; and
`FIG. 6 is a coagulating linear patch.
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`Referring now to the drawings, wherein like refer-
`ence numerals designate identical or corresponding
`parts throughout the several views, and more particu-
`larly to FIGS. 1A and 1B thereof, there is illustrated a
`coagulating forceps in accordance with the present
`invention.
`FIG. 1A and FIG. 1B show that the forceps 10 hav-
`ing handles 11 and 12 forming a scissor-like arrange-
`ment by which the jaws 20 and 30 are brought into
`contact with the compressed vessel or tissue 17 as
`shown in FIG. 1B. A plurality of electrodes 21 are
`shown on the upper jaw and a plurality of sensors 31 on
`the lower jaw. Although four electrodes 21 and four
`temperature sensors 31 are illustrated, any number and
`any arrangement or size of electrodes may be used de-
`pending upon the type of vessel or artery, vessel or
`other tissue which is to be cutoff. That is, for different
`
`5,443,463
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`4
`types of operations and for different types of arteries,
`vessels, or other tissues, different devices or forceps
`may be configured to conform with certain areas of the
`human body or certain access areas which are used in
`normal surgical procedures may be utilized. As an ex-
`ample, the forceps may be extended to form a needle-
`nose configuration or the size of the forceps may be
`reduced and accordingly the shape of the electrodes
`may be changed to take into account the size of the
`forceps. Furthermore, the configuration of the scissors-
`like arrangement is for purposes of illustration and the
`jaws may take the form of a clamping structure having
`either a straight head or an angled head as is normally
`used in any of a variety of clamping devices used for
`surgical procedures. Additionally,
`the scissors-like
`structure may be replaced with any other mechanism
`that will cause the forceps jaws to be brought together
`when activated. In particular, various types of mecha-
`nisms typically used in devices for laparoscopic surgery
`would be available.
`When the forceps of FIG. 1 are used, a two-step
`procedure is involved in order to cut the vessel. That is,
`first the forceps 10 are clamped across the vessel as
`shown in FIG. 1B and the tissue is heated for a predeter-
`mined period at a predetermined temperature in order
`to ensure the coagulation of the vessel. Then, the for-
`ceps is removed and a cutting device such as a knife or
`an electrosurgical cutting is used. This requirement of
`two devices in the two-step operation can be eliminated
`by the single device of FIG. 2B.
`The FIGS. 2A and 2B illustrate a bifurcated top jaw
`with the electrodes 21 on the top jaw being divided
`between each of the two parts 38 and 39 of the top jaw.
`The bottom jaw 41 is a flat surface having a groove 42.
`The bottom surface contains the sensors 46 identical to
`the sensors 31 in FIG. 1B. Also shown in the FIG. 2B is
`a cutting blade 49 schematically shown as attached to
`an electrosurgical unit power generator 50 of the type
`generally used for electrosurgical cutting procedure.
`With the arrangement of FIG. 2B, the multi-seg-
`mented electrodes are powered and the tissue is heated
`by the power source controller 150 until the com-
`pressed vessel is coagulated and then the cutting blade
`49, which slides between the upper jaws 38 and 39, cuts
`through the tissue into the lower groove 42. With the
`embodiment of FIG. 2B showing the connection of the
`cutting blade to the electrosurgical power unit 50, such
`cutting can occur by way of a normal electrosurgical
`action which involves a cutting by an are between the
`blade and the bottom of the groove 42 of the lower jaw
`41. Electrosurgical cutting requires less mechanical
`force and more completely assures the cutting of the
`tissue. Thus, a two-step operation is carried out using
`the same apparatus with the first step of the heating and
`coagulation of the tissue taking place separate from the
`actual cutting of the tissue. The cutting of the tissue is '
`completely independent of the operation of the multi-
`segmented electrodes which have already accom-
`plished the coagulation. When the cutting takes place,
`the power is no longer supplied to the multisegmented
`electrodes. Subsequently, the cutting blade either di-
`rectly by mechanical force or through the action of an
`electrosurgical cutting accomplishes the actual cutting
`through of the tissue whose blood supply has been cut
`off by the prior coagulation. Essentially, this amounts to
`stopping blood flow on two sides of an area and then the
`subsequent cutting in the middle of the area with the
`stopping of blood flow and the cutting is accomplished
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`by a single device. The FIG. 2C illustrates a side blade
`cutting structure with a single pair of upper and lower
`jaws 38 and 41. The lower groove 42 still retains the
`cutting blade 49 after passing through the tissue in a
`manner similar to FIG. 2B. The cutting action of the
`blade 49 can also be accomplished by an electro-surgi-
`cal action in a manner similar to previously described
`operation of the cutting blade of FIG. 2B. The excep-
`tion to the operation of the instrument of FIG. 2B is that
`the device of FIG. 2C has a cutoff of blood supply or a
`coagulation on only one side of the area to be cut. Side
`cutting would be accomplished by the operation of the
`device of FIG.‘2C is useful in particularized areas of
`surgery which either do not require cutoff of blood
`supply on both sides of the tissue to be cut or require or
`prefer continued blood supply flow adjacent to one side
`of the cut area.
`The FIG. 3 is a schematic representation of the
`power source controller 150 of FIGS. 2A and 2B and
`the switch matrix for the multi-segmented forceps dis-
`cussed in conjunction with either FIG. 1 or FIG. 2. The
`electrical
`leads connect
`to the electrode-thermistor
`pairs of the forceps by way of connectors 138. The
`thermistor leads of the thermistors 31 (46) are con-
`nected to the matrix switchbank 134 and the electrode
`leads of electrodes 21 are connected to the switchbank
`136. Each thermistor 31 (46) is sampled by means of a
`temperature measurement circuit 128 and the isolation
`amplifier 126 before being converted to digital form in
`the converter 116 and fed to the computer 114. The
`temperature measurement circuitry compares the mea-
`sured temperature with a thermistor reference voltage
`132. The electrode switch 136 is controlled in response
`to the output of the computer 114 by means of the opto-
`isolators 130. Input power from the RF input passes
`through the overvoltage and overcurrent protector 110
`and is filtered by the bandpass filter 122 before being
`subjected to overvoltage suppression by the suppression
`unit 124. The voltage is isolated by means of transform-
`ers 139, 140 and 142 with the transformer voltages V; 40
`and Vv from the transfonners 142 and 144 being con-
`verted by the RMS-DC converters 118 into an RMS
`voltage to be fed to the converters 116. Prior to conver-
`sion, the signals V,-and Vvare also fed to the high-speed
`analog multiplier 120. RF control from computer 114 is 45
`provided through interface 112.
`The FIG. 4 provides a schematic representation of
`the connection of power source controller 150 of FIG.
`3 to a multi-segmented electrode forceps having an
`illustrated four electrodes. The illustrated embodiment
`of FIG. 4 shows a monopolar construction having a
`connection to a patient ground pad 120. The electrodes
`121-124 may correspond to the electrodes 21 in FIG. 1b
`and may be located on the upper jaw 20 in line or they
`may be located as shown in FIG. 2 with two of the
`electrodes being on one of the upper split jaws 38 and
`the other two being on the upper split jaw 39. Although
`four electrodes are shown in the FIG. 4, there is no limit
`based upon the principles of operation. Neither is there
`a limit on the arrangement of a particular number of
`electrodes on a particular portion of the jaw. The nature
`of the surgery to be performed and particularly the
`nature of the device for performing such surgery will
`provide the impetus for the size of the electrodes and
`the number of electrodes and the positioning of the
`electrodes on the forceps.
`In the illustration of FIG. 4, there is a voltage from
`the controlled power source being fed to one or more of
`
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`6
`the electrodes 121-124 depending on the condition of
`the switches 111-114. This is a monopolar operation
`and the grounding occurs by way of the patient ground
`pad 120. The temperature sensors 31 are not shown in
`the FIG. 4 embodiment for purposes of simplification
`but would be clearly positioned in a manner similar to
`FIG. 1 and FIG. 2 and the outputs would be fed to the
`device of FIG. 3.
`Any large tissue area or vessel which needs to be
`coagulated can be covered by a number of electrodes by
`segmenting the large area into a number of smaller area
`electrodes of the type 121-124. With this type of struc-
`ture of smaller area electrodes, individual control of the
`energy to each electrode through the switching circuit
`of FIG. 4 is available in order to achieve controlled
`coagulation over a large area of tissue. The temperature
`sensors 31 or 46 are employed to sense the tissue tem-
`perature. Allowing the tissue temperature to reach a
`desired value and maintaining that temperature at that
`level for an appropriate period of time provides the
`physician with feedback concerning the coagulation
`process which would be impossible to achieve with a
`visible inspection of the surface tissue of the vessel
`being coagulated. This temperature feedback ideally
`provides for the control of the depth of the treatment
`and uses what is known as a “slow cook” of the tissue
`over a period of anywhere from several seconds to
`several minutes to achieve the desired therapeutic affect
`of cutting off the blood flow.
`'
`Studies of thermotolerance of cells indicate that
`maintaining cells at 43° C. for one hour produce a cell
`death. The time required is halved for each degree
`centigrade increase above 43“ C. Cell death occurs
`because cellular enzymes necessary to support metabo-
`lism are destroyed.
`The multi-electrodes/temperature feedback concept
`for coagulating large areas or linear regions can be
`improved with respect to the delivery of energy to
`particular points by way of the switching arrangement
`of FIG. 5 which provides for the ability to use either a
`monopolar operation or a bipolar operation. FIG. 5
`utilizes the same four electrodes 121-124 and a similar
`voltage source 150 with the same patient ground pad
`120 as used in FIG. 4. The essence of the FIG. 5
`monopolar/bipolar switching arrangement is that the
`physician or operator has the ability to provide either
`monopolar or bipolar operation. When switch 220 is
`closed and the switches 216-219 remain open, the de-
`vice functions essentially the same as the FIG. 4 em-
`bodiment. That is, it provides monopolar operation. On
`the other hand, if the switch 220 is opened and if pairs
`of switches, with one of the pair being selected from the
`switch 211 to 214 and the other being selected from 216
`to 219, are operated in proper conjunction, the elec-
`trodes 121-124 will provide a bipolar operation. As an
`example, if switch 214 is closed as well as switch 218,
`then the current will pass from electrode 121 to elec-
`trode 123. In a similar manner, if switch 213 is closed as
`well as switch 219, there will be a bipolar operation
`with current flowing between electrode 122 and 124.
`Bipolar operation is not limited to these 121-123 and
`122-124 pair couplings because if switch 214 and switch
`217 are closed there will be bipolar operation between
`the electrodes 121 and 122 with current passing from
`121 to 122.
`
`The embodiment of FIG. 5 not only provides a
`choice between monopolar and bipolar operation but
`also provides a flexibility within the bipolar operation
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`so that any two or any combination of pairs of elec-
`trodes 121-124 may be utilized together. Obviously, if
`switch 214 were thrown in conjunction with switch
`216, nothing would occur because there would be a
`short. The operation in a bipolar mode provides the 5
`additional flexibility whereby some of the electrodes
`may be positioned on the top half and the bottom half
`respectively of the jaws of the forceps 10. That is, in-
`stead of the forceps having the electrodes positioned in
`line on the top jaw 20 as shown in FIG. 1, they may be 10
`positioned with two electrodes 121-122 on a top jaw
`and electrodes 123 and 124 on the bottom jaw. Of
`course, the same remains true with respect to any num-
`ber of electrodes other than the four shown in the em-
`bodiment of FIGS. 4 and 5.
`The FIG. 6 illustrates an embodiment utilizing the
`electrode arrangement concept and the temperature
`sensor feedback concept to provide effectively a patch
`which may be used to control or stop surface bleeding.
`The patch contains multiple electrodes 330 and an asso-
`ciated temperature sensor 340 with the size of the patch
`350 being dependent upon physiologic considerations
`and desired area of coverage. The same is true with
`respect to the choice of the number of sensors and the
`number of associated electrodes. The feedback mecha-
`nism control by way of the FIG. 3 power source would
`function in the same manner except that a physician
`would control the operation of the feedback mechanism
`to provide temperatures which would correspond to
`the requirements of the injury on the surface of the
`person receiving this patch. Although the operation
`would be dependent upon the type of injury or the type
`of surface to be controlled with respect to blood flow, it
`provides a slow cooking process at a stabilized and
`controlled temperature so that all areas underneath the
`patch 350 may be treated in a uniform manner without
`“hot spots” which would cause either injury or undesir-
`able and uneven control of bleeding while also unneces-
`sarily cauterizing tissue.
`The use of a coagulating forceps provides uniform
`coagulation over large areas of tissue by providing the
`proper application of energy to provide the desired
`depth of penetration without reliance on a visible in-
`spection of the surface of the tissue or vessel being
`coagulated. The ability to segment the large area elec-
`trosurgical electrode into a number of smaller area elec-
`trodes and individually controlling the energy to each
`electrode through the multiplexing circuit of either
`FIG. 4 or 5 provides a degree of flexibility beyond the
`state of the art as well as a degree of assurance hereto-
`fore unknown. Thus use of many small electrodes is
`generally preferable to a single large electrode. The
`advantage of many small electrodes is better control
`such as the ability to cause tissue to reach a therapeutic
`temperature with a small amount of power.
`The temperature sensors provide the feedback mech-
`anism which allows the tissue temperature to reach a
`desired value and be maintained at that level for an
`appropriate period of time. This provides necessary
`information concerning the coagulation process which
`would otherwise be unavailable to the physician. The
`
`8
`monitoring of the tissue impedance and the actual deliv-
`ered power provide the ability to control the coagula-
`tion precisely. Once this coagulation is controlled to the
`satisfaction of the physician and the coagulating job has
`been completed, the cutting mechanism, either by way
`of electrosurgical cutting or manual cutting, severs the
`ligated vessel in the center of the coagulated area as
`shown in the embodiment of FIG. 2. Any number of
`sets of electrodes can be utilized depending upon the
`area and the location of the area to be coagulated and
`the head of the forceps can be angled or otherwise
`maneuvered using many of the same physiologic con-
`siderations provided for the selection of any surgical
`tool subject to electrical connection to the power gener-
`ation source and the number of wires and space re-
`quired for such connection.
`Obviously, numerous modifications and variations of
`the present invention are possible in light of the above
`teachings. It is therefore to be understood that within
`the scope of the appended claims, the invention may be
`practiced otherwise than as specifically described
`herein.
`What is claimed as new and desired to be secured by
`letters patent of the United States is:
`1. An implement for selectively coagulating blood
`vessels or tissues containing blood vessels, comprising:
`at least two opposable members and a means for per-
`mitting movement of said at least two opposable
`members toward and away from each other;
`electroconductive electrode means positioned on at
`least one of said at least two opposable members for
`effecting electrical contact with said vessels to be
`coagulated,
`said ' electroconductive
`electrode
`means includes a plurality of electrically isolated
`separate electrodes positioned on at least one of
`said at least two opposable members; and
`radio frequency power means connected to said elec-
`trodes for selectively delivering radio-frequency
`energy to each electrode to pass current through
`and coagulate said vessels positioned between said
`at least two opposable members,
`2. The implement according to claim 1, further in-
`cluding a switching means for providing individual
`control of energy to each of said electrically isolated
`separate electrodes.
`3. The implement according to claim 2, wherein said
`switching means includes means for selecting at least
`one of monopolar and bipolar energy to be delivered to
`each of said electrically isolated separate electrodes.
`4. The implement according to claim 3, wherein said
`switching means includes means for providing bipolar
`energy to said electrodes.
`5. The implement according to claim 1, and further
`including temperature ‘sensing means positioned on at
`least one of said at least two opposable members for
`measuring the temperature of said vessels in close prox-
`imity to said electrodes.
`6. The implement according to claim 1, wherein elec-
`troconductive electrode means are positioned on both
`opposable members.*
`*
`*
`Ik
`*
`
`10
`
`

`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`CERTIFICATE OF CORRECTION
`
`PATENT NO.
`
`:
`
`5 ,443 .463
`
`DATED
`
`5 August 22, 1.995
`
`INVENTOWS): Roger A. Stern, et. al.
`
`It is certified that error appears in the above-indentified patent and that said Letters Patent is hereby
`corrected as shown below:
`
`item [63], under Related U.S. Application Data:
`Title page,
`11;, 1992" should‘read—-April 14, 1993--.
`
`"April
`
`Signed and Sealed this
`
`Twenty-first Day of November, 1995
`
`flaw“
`
`BRUCE LEI-IMA.\'
`
`Arresting Oflicer
`
`Co/7rIni.r.x'ir2Iz:.'rr1f Ptuenlx and Tradcnxurlm
`
`11