Abstract: The present invention is directed towards an electrosurgical cutting system. The system comprises an electrically conductive blade, having first and second blade surfaces. First and second insulators are affixed to the first and second blade surfaces, respectively. A blade edge, a region between the first and second blade surfaces, has an edge radius of curvature, which preferably is small. A source of pulsed electrical energy coupled to the electrically conductive blade provides a substantially uniform and highly enhanced electric field along a cutting portion of the blade edge. The system can also be comprised of a wire electrode. Despite the fact that its field is strongly enhanced around the apex, a uniform vapor cavity is formed and then ionized using an appropriately designed burst of pulses, preferably of alternating polarity.

Abstract: An apparatus and method for cutting a material including conducting and non-conducting materials such as biological tissue, cellulose or plastic while the material is submerged in a conductive liquid medium. The apparatus has a cutting electrode with an elongate cutting portion having an aspect ratio (length to width) of 1 or more and a return electrode. The two electrodes are immersed in the conductive medium and a voltage is applied between them to heat the medium, thus producing a vapor cavity around the elongate cutting portion and ionizing a gas inside the vapor cavity to produce a plasma. The voltage applied between the electrodes is modulated in pulses having a modulation format selected to minimize the size of the vapor cavity, its rate of formation and heat diffusion into the material while the latter is cut with an edge of the elongate cutting portion. The modulation format includes pulses ranging in duration from 10 ?s to 10 ms, as well as minipulses and micropulses, as necessary.

Abstract: An apparatus and method for cutting a material including conducting and non-conducting materials such as biological tissue, cellulose or plastic while the material is submerged in a conductive liquid medium. The apparatus has a cutting electrode with an elongate cutting portion having an aspect ratio (length to width) of 1 or more and a return electrode. The two electrodes are immersed in the conductive medium and a voltage is applied between them to heat the medium, thus producing a vapor cavity around the elongate cutting portion and ionizing a gas inside the vapor cavity to produce a plasma. The voltage applied between the electrodes is modulated in pulses having a modulation format selected to minimize the size of the vapor cavity, its rate of formation and heat diffusion into the material while the latter is cut with an edge of the elongate cutting portion. The modulation format includes pulses ranging in duration from 10 &mgr;s to 10 ms, as well as minipulses and micropulses, as necessary.

Abstract: An apparatus and method for cutting a material including conducting and non-conducting materials such as biological tissue, cellulose or plastic while the material is submerged in a conductive liquid medium. The apparatus has a cutting electrode with an elongate cutting portion having an aspect ratio (length to width) of 1 or more and a return electrode. The two electrodes are immersed in the conductive medium and a voltage is applied between them to heat the medium, thus producing a vapor cavity around the elongate cutting portion and ionizing a gas inside the vapor cavity to produce a plasma. The voltage applied between the electrodes is modulated in pulses having a modulation format selected to minimize the size of the vapor cavity, its rate of formation and heat diffusion into the material while the latter is cut with an edge of the elongate cutting portion. The modulation format includes pulses ranging in duration from 10 &mgr;s to 10 ms, as well as minipulses and micropulses, as necessary.

Abstract: An apparatus and method for cutting a material including conducting and non-conducting materials such as biological tissue, cellulose or plastic while the material is submerged in a conductive liquid medium. The apparatus has a cutting electrode with an elongate cutting portion having an aspect ratio (length to width) of 1 or more and a return electrode. The two electrodes are immersed in the conductive medium and a voltage is applied between them to heat the medium, thus producing a vapor cavity around the elongate cutting portion and ionizing a gas inside the vapor cavity to produce a plasma. The voltage applied between the electrodes is modulated in pulses having a modulation format selected to minimize the size of the vapor cavity, its rate of formation and heat diffusion into the material while the latter is cut with an edge of the elongate cutting portion. The modulation format includes pulses ranging in duration from 10 &mgr;s to 10 ms, as well as minipulses and micropulses, as necessary.