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  Bipolar cutting and coagulating forcepsUSPTO Application #: 20070299439Title: Bipolar cutting and coagulating forceps Abstract: A bipolar electrosurgical instrument comprises a handle (5), a body (1) joined to the handle, and a jaw assembly (12) joined to the body and arranged such that manipulation of the handle allows the opposed jaws of the jaw assembly to be opened and closed with respect to one another. A first of said opposed jaws (14) has at least a first coagulating electrode, and the other of said opposed jaws (13) has at least a second coagulating electrode and a cutting electrode (16) separated from the second coagulating electrode by an insulating member (17). The instrument is manipulated at the surgical site such that the jaws of the jaw assembly (12) are open with respect to one another, with the cutting electrode (16) and at least one of the first and second coagulating electrodes contacting tissue at the surgical site. A radio frequency electrosurgical signal is supplied between the cutting electrode and the at least one coagulating electrode, and the electrosurgical instrument is moved while maintaining the jaws (13, 14) in their open position so as to cut tissue at the surgical site. (end of abstract)
Agent: Nikolai & Mersereau, P.A. - Minneapolis, MN, US Inventors: Scott T. Latterell, Douglas S. Wahnschaffe, Scott R. Sanders, Nigel Mark Goble, Colin Charles Owen USPTO Applicaton #: 20070299439 - Class: 606048000 (USPTO) Related Patent Categories: Surgery, Instruments, Electrical Application, Applicators, Cutting, Bipolar Electrodes The Patent Description & Claims data below is from USPTO Patent Application 20070299439. Brief Patent Description - Full Patent Description - Patent Application Claims
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to a method of electrosurgically cutting tissue, and to an electrosurgical system for cutting tissue. [0003] 2. Discussion of the Prior Art [0004] Electrosurgical cutting forceps are a commonly used tool in electrosurgery. U.S. Pat. No. 5,445,638 is a typical example, in which a pair of jaws are used to grip and coagulate tissue, and then a mechanical cutting blade moves between the jaws in order to cut the tissue. U.S. Pat. No. 6,554,829 is a more recent version of this type of instrument, still employing a pair of jaws and a mechanical cutting blade. [0005] An alternative form of cutting forceps uses an electrosurgical cutting member as opposed to a mechanical cutting member. U.S. Pat. No. 6,174,309 is one such example, in which tissue is grasped between jaws, and then an electrosurgical cutting voltage is supplied to a cutting member located on one of the jaws. In all of these devices, the amount of tissue able to be cut is limited by the size of the jaws used to grasp the tissue while it is being cut. [0006] The present invention attempts to provide an improvement over these prior art cutting devices, especially in that the cutting of relatively larger amounts of tissue is facilitated. SUMMARY OF THE INVENTION [0007] Accordingly, the invention provides a method of electrosurgically cutting tissue at a surgical site comprising the steps of [0008] (i) providing a bipolar electrosurgical instrument including a handle, a jaw assembly arranged such that manipulation of the handle allows the opposed jaws of the jaw assembly to be opened and closed with respect to one another; a first of said opposed jaws having at least a first coagulating electrode; the other of said opposed jaws having at least a second coagulating electrode; and a cutting electrode separated from the second coagulating electrode by an insulating member, [0009] (ii) manipulating the electrosurgical instrument at the surgical site such that the jaws of the jaw assembly are open with respect to one another, with the cutting electrode and at least one of the first and second coagulating electrodes contacting tissue at the surgical site, [0010] (iii) supplying a radio frequency electrosurgical signal between the cutting electrode and the at least one coagulating electrode, and [0011] (iv) moving the electrosurgical instrument while maintaining the jaws in their open position so as to cut tissue at the surgical site. [0012] Unlike the prior art devices, in which only tissue grasped between the jaws is cut, the present method moves the instrument with its jaws in the "open" position in order to cause tissue cutting. Preferably the electrosurgical instrument has a longitudinal axis and the instrument is moved longitudinally along said axis in order to cut tissue at the surgical site. Conveniently the first jaw has an inner face opposite the second jaw, and the cutting electrode is positioned on the inner face of the first jaw. In one convenient arrangement, the cutting electrode comprises a longitudinally extending rail. [0013] The method of the present invention also allows the electrosurgical instrument to be used to coagulate as well as cut tissue. Accordingly, the method includes the additional steps of manipulating the handle in order to close the jaw assembly such that tissue at the surgical site is grasped therebetween, and supplying a radio frequency electrosurgical signal between the first and second coagulating electrodes so as to cause the coagulation of the tissue grasped between the jaws. In one arrangement the coagulation step is carried out following the movement of the instrument in order to cut tissue at the surgical site. In this way, the instrument can be used in order to control any bleeding caused by the cutting of the tissue. [0014] Alternatively, the method includes the step of supplying a combined radio frequency signal consisting of a first cutting RF signal and a second coagulating RF signal, the first RF cutting signal being delivered between the cutting electrode and the at least one coagulating electrode, and the second coagulating RF signal being delivered between the first and second coagulating electrodes. In this way, the instrument is capable of simultaneously delivering a coagulating signal to the tissue as the tissue is being cut by the movement of the instrument. In a preferred arrangement, the combined radio frequency signal comprises a signal alternating constantly between the first cutting RF signal and the second coagulating RF signal so that the two are interleaved. There may also conveniently be provided adjustment means for varying the ratio of the blend mode so as to vary that part of the blend signal that is the first RF cutting signal as compared with the part of the blend signal that is the second RF coagulating signal. The adjustment means is conveniently operable by the user of the electrosurgical instrument, but can alternatively be automatically adjusted in response to feedback from one or more sensors detecting a parameter of the tissue, such as electrical impedance. [0015] By the terms "RF cutting signal" and "RF coagulating signal" there is hereby meant any RF signal capable of cutting or coagulating tissue respectively. For example the signals may differ with respect to their voltage, the RF cutting signal having a higher voltage such that it is capable of cutting tissue, whereas the RF coagulating signal having a relatively lower voltage such that it is capable of coagulating but not cutting tissue. Additionally or alternatively, the RF cutting signal may differ from the RF coagulating signal in terms of its waveform rather than voltage. For example the RF coagulating signal may comprise shorter bursts of the same signal used for the cutting of tissue. [0016] Where the terms "coagulate" or coagulating" are used, there is hereby meant the prevention of bleeding following a tissue-cutting operation, as well as a process in which the collagen within tissue is made viscous so as to prevent blood flow through a blood vessel, for example prior to cutting. The terms are also herein meant to include vessel sealing, in which the walls of the vessel are fused together in order to seal the vessel. [0017] The invention further resides in an electrosurgical system comprising [0018] (i) a bipolar electrosurgical instrument including a handle, a jaw assembly arranged such that manipulation of the handle allows the opposed jaws of the jaw assembly to be opened and closed with respect to one another; a first of said opposed jaws having at least a first coagulating electrode; the other of said opposed jaws having at least a second coagulating electrode; and a cutting electrode separated from the second coagulating electrode by an insulating member, and [0019] (ii) an electrosurgical generator comprising one or more sources of RF output power, a controller operable to control the generator such that it is capable of providing a first cutting RF signal to the electrosurgical instrument or a second coagulating RF signal to the electrosurgical instrument, and, in a combined mode, to deliver both first and second RF signals, the signals being fed to the electrosurgical instrument such that, in the combined mode, the cutting signal is delivered between the cutting electrode and at least one of the first and second coagulating electrodes, and the coagulating RF signal is delivered between the first and second coagulating electrodes. [0020] As described in our co-pending UK patent application 0305018.4, the generator may comprise a single RF source so that in the combined mode the generator system alternates constantly between delivering the cutting and coagulating signals. Alternatively, the generator comprises first and second RF sources operating at different frequencies, so as to deliver the cutting and coagulating signals simultaneously. As described in the patent application mentioned above, there is conceivably provided adjustment means for varying the ratio of the combined mode so as to vary that part of the combined signal that is the first RF cutting signal as compared with the part of the combined signal that is the second RF coagulating signal. Conveniently, the adjustment means is operable by the user of the electrosurgical instrument, but it may conceivably also be automatically adjusted in response to feedback from one or more sensors detecting a parameter of the tissue, such as the tissue impedance. [0021] The invention also resides in a bipolar electrosurgical instrument including a handle, a jaw assembly arranged such that manipulation of the handle allows the opposed jaws of the jaw assembly to be opened and closed with respect to one another; a first of said opposed jaws having at least a first coagulating electrode; the other of said opposed jaws having at least a second coagulating electrode; and a cutting electrode and separated from the second coagulating electrode by an insulating member, wherein the cutting electrode is in the form of a longitudinal rail mounted on the insulating member, the rail protruding from the insulating member by a distance of less than 100 microns. The dimensions of the rail have been found to be very important for ensuring that an effective electrosurgical cut occurs. Preferably the rail protrudes from the insulating member by a distance of between 25 and 75 microns, more preferably between 40 and 60 microns, and most preferably approximately 50 microns. Preferably, the width of the rail is between 25 and 75 microns, more preferably between 40 and 60 microns, and most preferably approximately 50 microns. [0022] According to a further aspect of the invention, a method of electrosurgically cutting tissue at a surgical site comprises the steps of Continue reading... Full patent description for Bipolar cutting and coagulating forceps Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Bipolar cutting and coagulating forceps patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Bipolar cutting and coagulating forceps or other areas of interest. ### Previous Patent Application: Energy based devices and methods for treatment of patent foramen ovale Next Patent Application: Electrosurgical apparatus and method for coagulative treatments through radiofrequency Industry Class: Surgery ### FreshPatents.com Support Thank you for viewing the Bipolar cutting and coagulating forceps patent info. IP-related news and info Results in 1.21062 seconds Other interesting Feshpatents.com categories: Medical: Surgery , Surgery(2) , Surgery(3) , Drug , Drug(2) , Prosthesis , Dentistry |
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