MULTIELECTRODE ELECTROSURGICAL INSTRUMENT

摘要

An improved electrosurgical instrument and method is disclosed for simplifying making incisions and other treatments using electrosurgery. The electrosurgical instrument comprises a body having more than two electrodes with at least two electrodes having alternating current power supplied to them such that they comprise a bipolar alternating current configuration and employ a means other than electrode spacing, composition, or geometry for reducing or preventing accumulation of eschar that would otherwise form a short circuit current path and interfere with obtaining a predetermined surgical effect. In one aspect, such means for reducing or preventing eschar accumulation consists of at least one other electrode having a direct current voltage between it and at least one of the two electrodes forming the alternating current bipolar configuration. In another aspect of the invention two or more pairs of alternating current electrodes comprising bipolar electrodes are powered with alternating current having a nonzero RMS voltage sufficient to at least reduce eschar accumulations on one electrode or induce electrolysis of at least one component of a medium surrounding at least one pair of bipolar electrodes. The electrodes are separated from each other using electrically insulating materials such that electric current does not flow between at least two of the bipolar alternating current electrodes unless they contact at least one other electrically conductive medium, such as patient tissue or a medium comprising at least in part a solid, liquid, gas, or ionized component that allows electric current to flow between electrodes. In the aspect where at least one electrode is powered by direct current the electrodes are configured such that electrical current does not flow between at least one of the bipolar alternating current electrodes and at least one of the direct current electrodes unless one or more media, such as patient tissue or a medium comprising at least in part a solid, liquid, gas, or ionized component that allows electric current to flow between electrodes, are contacting or adjacent to the electrodes having a direct current voltage difference between them. The assembly comprised of the electrodes and the separating insulating materials may also employ one or more means to reduce the current flowing between them that does not produce a desired predetermined surgical effect with one aspect of such means being using an outer insulating coating configured such that one or more portions of at least one of the bipolar alternating electrodes are insulated while leaving exposed other portions of such insulated electrodes so that they are capable of being in electrical communication with tissue or at least one material in electrical communication with tissue.