Abstract: Electrosurgery method and apparatus. In the method, tissue is cut or coagulated, with an electrically low conductive liquid providing cooling. In another method, skin is cut by electrosurgery in a dry field using a low duty cycle signal energizing the cutting electrode, minimizing tissue charring. A combination coagulation and cutting electrode performs both functions. The cutting is performed by a blade edge generating a local plasma adapted for cutting. Superimposed on the blade edge is an electrode of greater surface area electrically insulated from the cutting electrode, for coagulation. In another version, a single component cutting/coagulation blade (electrode) has a cutting and a flat partially insulated portion defining through holes in the insulation for coagulation. Also provided is an electrical circuit whereby each electrode is isolated by a filter from cross talk and feedback of the RF signal from the other electrode, minimizing arcing.

Abstract: Methods and devices for the non-thermal, electrically-induced temporary or permanent closure of blood vessels. Methods and devices employ pulsed electrical energy according to a defined regime to effect controlled occlusion of targeted blood vessels without heating the vessel and with minimal damage to adjacent tissue. The extent of vessel closure, i.e., temporary (vasoconstriction) or permanent (thrombosis), is controlled based on the manipulation of various parameters of the electrical stimulation regime as well as the configuration of the electrodes used to apply the regime.

Abstract: Electrosurgery method and apparatus. In the method, tissue is cut or coagulated, with an electrically low conductive liquid providing cooling. In another method, skin is cut by electrosurgery in a dry field using a low duty cycle signal energizing the cutting electrode, minimizing tissue charring. A combination coagulation and cutting electrode performs both functions. The cutting is performed by a blade edge generating a local plasma adapted for cutting. Superimposed on the blade edge is an electrode of greater surface area electrically insulated from the cutting electrode, for coagulation. In another version, a single component cutting/coagulation blade (electrode) has a cutting and a flat partially insulated portion defining through holes in the insulation for coagulation. Also provided is an electrical circuit whereby each electrode is isolated by a filter from cross talk and feedback of the RF signal from the other electrode, minimizing arcing.

Abstract: Described herein are methods and apparatus for cutting a material including biological tissue. The apparatus has a cutting electrode with an elongate cutting portion. A voltage pulse waveform (typically comprising repeated bursts of minipulses) having a low or very low duty-cycle is applied to the cutting electrode to cut the tissue or other material by producing a vapor cavity around the cutting portion of the electrode and ionizing a gas inside the vapor cavity to produce a plasma. A low duty cycle cutting waveform may prevent heat accumulation in the tissue, reducing collateral thermal damage. The duration of the burst of minipulses typically ranges from 10 ?s to 100 ?s, and the rep rate typically ranges from 1 KHz to 10 Hz, as necessary. The apparatus and method of invention may cut biological tissue while decreasing bleeding and maintaining a very shallow zone of thermal damage.

Abstract: Methods and devices for the non-thermal, electrically-induced temporary or permanent closure of blood vessels. The subject methods and devices employ pulsed electrical energy according to a defined regime to effect controlled occlusion of targeted blood vessels without heating the vessel and with minimal damage to adjacent tissue. The extent of vessel closure, i.e., temporary (vasoconstriction) or permanent (thrombosis), is controlled based on the manipulation of various parameters of the electrical stimulation regime as well as the configuration of the electrodes used to apply the regime.

Abstract: The present invention provides a method of treating an ocular disease in a subject. In a first step, a nucleic acid is introduced into cells or a tissue. The nucleic acid is introduced by electron avalanche transfection. With this technique, a high electric field induces a vapor bubble and plasma discharge between an electrode and the surrounding medium. The formation of a vapor bubble generates mechanical stress. Plasma discharge through the ionized vapor in the bubble enables connectivity between the electrode and the surrounding medium, so that mechanical stress and electric field are applied simultaneously, which results in permeabilization of the cells or tissue. This permeabilization in turn allows the nucleic acid to enter the cell or tissue. Cells or tissue containing the nucleic acid are then transplanted into an ocular region of the subject.

Abstract: Described herein are methods and apparatus for cutting a material including biological tissue. The apparatus has a cutting electrode with an elongate cutting portion. A voltage pulse waveform (typically comprising repeated bursts of minipulses) having a low or very low duty-cycle is applied to the cutting electrode to cut the tissue or other material by producing a vapor cavity around the cutting portion of the electrode and ionizing a gas inside the vapor cavity to produce a plasma. A low duty cycle cutting waveform may prevent heat accumulation in the tissue, reducing collateral thermal damage. The duration of the burst of minipulses typically ranges from 10 ?s to 100 ?s, and the rep rate typically ranges from 1 KHz to 10 Hz, as necessary. The apparatus and method of invention may cut biological tissue while decreasing bleeding and maintaining a very shallow zone of thermal damage.

Abstract: The present invention provides a method and apparatus for transferring an agent into a cell. The method includes the steps of providing an agent outside of a cell and generating a vapor bubble and a plasma discharge between an avalanche electrode and a conductive fluid surrounding the cell. The vapor bubble and plasma discharge generate a mechanical stress wave and an electric field, respectively. The combination of this mechanical stress wave and electric field results in permeabilization of the cell, which in turn results in transfer of the agent into the cell.

Abstract: System and method for making incisions in eye tissue at different depths. The system and method focuses light, possibly in a pattern, at various focal points which are at various depths within the eye tissue. A segmented lens can be used to create multiple focal points simultaneously. Optimal incisions can be achieved by sequentially or simultaneously focusing lights at different depths, creating an expanded column of plasma, and creating a beam with an elongated waist.

Abstract: System and method for making incisions in eye tissue at different depths. The system and method focuses light, possibly in a pattern, at various focal points which are at various depths within the eye tissue. A segmented lens can be used to create multiple focal points simultaneously. Optimal incisions can be achieved by sequentially or simultaneously focusing lights at different depths, creating an expanded column of plasma, and creating a beam with an elongated waist.

Abstract: The present invention provides a method and apparatus for transferring an agent into a cell. The method includes the steps of providing an agent outside of a cell and generating a vapor bubble and a plasma discharge between an avalanche electrode and a conductive fluid surrounding the cell. The vapor bubble and plasma discharge generate a mechanical stress wave and an electric field, respectively. The combination of this mechanical stress wave and electric field results in permeabilization of the cell, which in turn results in transfer of the agent into the cell.

Abstract: Patterned laser treatment of the retina is provided. A visible alignment pattern having at least two separated spots is projected onto the retina. By triggering a laser subsystem, doses of laser energy are automatically provided to at least two treatment locations coincident with the alignment spots. All of the doses of laser energy may be delivered in less than about 1 second, which is a typical eye fixation time. A scanner can be used to sequentially move an alignment beam from spot to spot on the retina and to move a treatment laser beam from location to location on the retina.

Abstract: Patterned laser treatment of the retina is provided. A visible alignment pattern having at least two separated spots is projected onto the retina. By triggering a laser subsystem, doses of laser energy are automatically provided to at least two treatment locations coincident with the alignment spots. All of the doses of laser energy may be delivered in less than about 1 second, which is a typical eye fixation time. A scanner can be used to sequentially move an alignment beam from spot to spot on the retina and to move a treatment laser beam from location to location on the retina.

Abstract: The present invention provides a method and apparatus for transferring an agent into a cell. The method includes the steps of providing an agent outside of a cell and generating a vapor bubble and a plasma discharge between an avalanche electrode and a conductive fluid surrounding the cell. The vapor bubble and plasma discharge generate a mechanical stress wave and an electric field, respectively. The combination of this mechanical stress wave and electric field results in permeabilization of the cell, which in turn results in transfer of the agent into the cell.

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: Electrosurgical therapy is provided with an electrode array configured to ablate tissue during insertion of the electrode array into tissue being treated. Once the electrode array is fully inserted, deep heating of the treated tissue can be performed by applying an additional waveform to the tissue with the electrode array. Optionally, the electrical waveform can be varied continuously during insertion of the electrode array to control the extent of coagulation at the side walls and at the bottom of the channels produced by tissue ablation.

Abstract: Patterned laser treatment of the retina is provided. A visible alignment pattern having at least two separated spots is projected onto the retina. By triggering a laser subsystem, doses of laser energy are automatically provided to at least two treatment locations coincident with the alignment spots. All of the doses of laser energy may be delivered in less than about 1 second, which is a typical eye fixation time. A scanner can be used to sequentially move an alignment beam from spot to spot on the retina and to move a treatment laser beam from location to location on the retina.

Abstract: System and method for making incisions in eye tissue at different depths. The system and method focuses light, possibly in a pattern, at various focal points which are at various depths within the eye tissue. A segmented lens can be used to create multiple focal points simultaneously. Optimal incisions can be achieved by sequentially or simultaneously focusing lights at different depths, creating an expanded column of plasma, and creating a beam with an elongated waist.

Abstract: The safe therapeutic window for laser medicine (a ratio of the threshold power for detrimental outcome to that of a desired outcome) tends to decrease as pulse length decreases. This problem is addressed by use of beam shapes and/or pulse shapes that improve temperature uniformity in the treated tissue. A beam shape with an adjustable on-axis intensity minimum improves spatial temperature uniformity in treated tissue. A pulse shape with a relatively intense early part (to set the temperature rise), followed by a less intense late part having decreasing intensity with time (to maintain a constant or nearly constant temperature rise) improves temporal temperature uniformity in the treated tissue. A therapeutic window (TW) of at least 3 is often required to provide a sufficient safety margin in practice. In one experiment, it was demonstrated that the minimum pulse length to provide a TW of 3 could be decreased from 20 ms to 10 ms following these principles.

Abstract: The present invention is directed towards an electrosurgical cutting system. The system comprises an electrically conductive blade, having an uninsulated cutting edge that is surrounded by an insulator. A source of pulsed electrical energy may be coupled to the electrically conductive blade to provide a substantially uniform and highly enhanced electric field along a cutting portion of the blade edge. The blade may have a uniform rate of erosion during use, so that both the conductive metal edge and the surrounding insulation layer erode at approximately the same rate. Also described are methods of fabricating insulated cutting electrodes, particularly blade electrodes.