Abstract: In some examples, nerves surrounding arteries or leading to organs are targeted with energy sources to correct or modulate physiologic processes. In some examples, different types of energy sources are utilized singly or combined with one another. In some examples, bioactive agents or devices activated by the energy sources are delivered to the region of interest and the energy is enhanced by such agents or the agents are enhanced by the energy sources.

Abstract: A medical probe, including an ablation electrode and a first conductor connected to the ablation electrode. The first conductor is configured to convey ablation energy to the ablation electrode. The probe also includes a second conductor which is connected at a junction to the first conductor so as to form a thermocouple at the junction.

Abstract: A system for measuring real-time tissue reflection spectral characteristics during ablation includes a catheter for collecting light reflected from tissue undergoing ablation, a detection component for separating constituent wavelengths of the collected light, a quantification apparatus for generating measured light intensity data of the collected light, and a processor for analyzing the data in relation to time. A method for monitoring formation of steam pop during ablation includes delivering light to tissue, delivering ablative energy to the tissue, measuring the reflectance spectral intensity of the tissue, and observing whether the measured reflectance spectral intensity (MRSI) initially increases in a specified time period followed by a decrease at a specified rate. If the MRSI does not decrease, delivery of ablation energy continues.

Abstract: An ablation therapy system and systematic method is provided for treating continuous atrial fibrillation. The therapy system includes a Multi-Channel RF Ablation Generator, an ECG interface, an assembly of at least three ablation catheters, and an ECG interface operably coupling and interfacing the catheters to both an ECG unit and the RF Ablation Generator. The systematic method includes transseptally accessing the Left Atrium (LA) through the septum of the patient's heart, and performing an endocardial pulmonary vein ablation procedure on the pulmonary vein ostial tissue surrounding one or more pulmonary veins in a manner treating aberrant conductive pathways therethrough. After performing the pulmonary vein ablation, the method further includes performing an endocardial atrial septum ablation procedure on the septal tissue in a manner treating aberrant conductive pathways therethrough.

Abstract: An electromagnetic shield apparatus is provided for an existing electrosurgical unit (ESU) including a pencil assembly and return pad assembly. The pencil assembly includes a pencil, pencil-assembly cable and terminal couplable to the ESU, and the return pad assembly includes a return pad, return-pad-assembly cable and return-pad-assembly terminal couplable to the ESU. The electromagnetic shield apparatus includes an electrically-conductive shield, a low-impedance, electrically-passive termination jumper and an insulated, low-impedance conductive cable. The electrically-conductive shield is configured for placement over the pencil-assembly cable to thereby cover and extend coaxially with the pencil-assembly cable. The termination jumper is couplable to and between the return-pad-assembly terminal and ESU, and the conductive cable is coupled to and between the electrically-conductive shield and termination jumper.

Abstract: Cardiac ablation systems and methods of their use and manufacture involve an ablation mechanism, a stabilizer mechanism, and a cinching mechanism that urges the ablation mechanism toward a patient tissue. Embodiments encompass methods for administering epicardial and endocardial lesions, including box lesions and connecting lesions, to patient tissue.

Abstract: A system for determining proximity of a surgical device relative to an anatomical structure includes at least one surgical device having a sensor assembly operably coupled to a processing unit and configured to transmit at least one electrical signal generated by the processing unit through a target anatomical structure to elicit a measurable response from the target anatomical structure. The processing unit is configured to calculate a signature property value of the target anatomical structure based on the measurable response. The processing unit is configured to identify the target anatomical structure based on a comparison between the signature property value and at least one other signature property.

Abstract: An electrosurgical system is provided that includes an electrosurgical generator configured to output a first electrosurgical waveform and a probe configured to deliver a second electrosurgical waveform to tissue. The system also includes an adapter coupled between the electrosurgical generator and the probe and operable to convert the first electrosurgical waveform to the second electrosurgical waveform. The adapter includes a step down transformer configured to convert the first electrosurgical waveform to the second electrosurgical waveform.

Abstract: An electrosurgical generator configured to output radio frequency (RF) energy having a current-source type behavior is provided. The generator has a buck converter having a voltage source, at least one switch and an inductor. The generator also has an RF stage configured to output the RF energy. A sensor circuit configured to measure at least one parameter of the RF energy and a controller configured to receive the measured parameter from the sensor circuit and control the output of the electrosurgical generator based on the measured parameter may also be provided in the electrosurgical generator.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue and treatment of cardiac arrhythmia. An ablation system includes an ablation catheter that has an array of ablation elements and a location element, an esophageal probe also including a location element, and an interface unit that provides energy to the ablation catheter. The distance between the location elements, determined by calculating means of the system, can be used by the system to set or modify one or more system parameters.

Abstract: An acoustic driver system for use in applying an oscillating stress to a subject undergoing a magnetic resonance elastography (MRE) examination includes a flexible passive driver located in the bore of the magnet and in contact with the subject. A remotely located active driver is acoustically coupled to the passive driver and produces acoustic energy in response to an applied current. The passive driver produces shear waves in response to the acoustic energy and are directed into the body of the subject undergoing the MRE examination.

Abstract: Disclosed herein are methods of and systems for predicting recurrence of atrial fibrillation comprising protease and protease inhibitor profiling.

Abstract: A method and apparatus include determining a value of a parameter associated with operation of an electrosurgical probe having a particular probe design, and determining whether the value of the parameter is within a range of values that has been predetermined for the particular probe design to indicate that the probe is treating tissue in a desired manner. Power is delivered to the probe according to an algorithm based upon a determination that the value of the parameter is outside the range of values The algorithm delivers power in a pulsed profile including portions of low power and portions of high power. In one embodiment, the tissue treatment is ablation, the parameter is impedance, and the method limits tissue necrosis to less than 200 microns. In another embodiment, the tissue treatment is shrinkage, the parameter is temperature, and the method limits power delivery when the probe is not shrinking tissue.

Abstract: An energy delivery system for controlling blood loss is provided. The system includes an energy-activated patch configured for placement on tissue. The patch includes an energy-delivering layer configured to deliver energy to the tissue. The system also includes an energy source in operative engagement with the energy-activated patch for energizing the energy-delivering layer.

Abstract: An end effector assembly for use with an instrument for sealing and cutting tissue includes a pair of opposing first and second jaw members movable relative to the to grasp tissue therebetween. Each jaw member including a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. One of the electrically conductive surfaces including a channel defined therein and extending along a length thereof that communicates with a nozzle disposed in the jaw housing. The nozzle is configured to direct high pressure fluid from a fluid source into the channel for cutting tissue grasped between the jaw members.

Abstract: The invention provides a system and method for achieving the cosmetically beneficial effects of shrinking collagen tissue in the dermis or other areas of tissue in an effective, non-invasive manner using an array of electrodes. Systems described herein allow for improved treatment of tissue. Additional variations of the system include array of electrodes configured to minimize the energy required to produce the desired effect.

Abstract: An endotracheal tube usable for intraopertive monitoring of the laryngeal nerve. The endotracheal tube includes at least one electrical contact that is movable along and about an exterior sidewall of the endotracheal tube and connected to the exterior sidewall by a connector when the electrode is placed in a position to optimize the conductivity between the nerve being monitored and the electrical contact. The electrical contact may be connected using a locking tube, tape, adhesive, etc.

Abstract: A surgical antenna for radiating microwave energy (e.g. frequency 500 MHz to 60 GHz) from a e.g. ceramic insertion tip (60) into biological tissue is disclosed. The tip is provided at the end of an elongate body which delivers the microwave energy to the tip via an inner conductor (30), an outer conductor (20) surrounding the inner conductor and a dielectric material (50) therebetween. The impedance of the insertion tip (60) is selected to improve impedance matching with the complex conjugate of the complex impedance of the tissue at a treatment frequency. For example the insertion tip may act as or include at least one quarter wavelength impedance transformer. By closely matching the antenna's impedance to the tissue, dynamic tuning (if used) can be performed much more efficiently. Impedance matching at the tip can also focus the radiated energy distribution.

Abstract: A surgical apparatus for performance of a surgical procedure on body tissue is provided and includes a housing, an elongate tubular member, a drive assembly, an electrical coupling component, and an electrical wire. The elongate tubular member is at least partially supported by the housing and defines a center lumen and a longitudinal axis. The drive assembly extends from the housing into the center lumen of the elongate tubular member. The electrical coupling component is located about the drive assembly. The electrical wire extends from within the housing into the elongate tubular member. The electrical wire is wrapped about the electrical coupling component, which allows the elongate tubular member to rotate about the longitudinal axis while allowing the electrical wire to be fixed within the housing and the elongate tubular member.

Abstract: A method and system for treating ventricular tachycardia (VT) by ablating scarred myocardial tissue containing a reentrant VT circuit. The method generally includes measuring electrical activity at a plurality of sites within a heart, identifying an area of scarred myocardial tissue based at least in part on the electrical activity measurements, and ablating substantially all of the scarred area. The system generally includes a medical device having a distal end, a plurality of electrical conduction sensors coupled to the distal end, and a console in communication with the distal end of the device, the console including a computer with display. The computer may be programmed to identify optimal ablation sites within a target tissue and the location of an isthmus associated with a reentrant VT circuit within a target tissue, the identifications being based at least in part on the measurements of the electrical conduction sensors.

Abstract: A system that interfaces with a workstation endocardial mapping system allows for the rapid and successful ablation of cardiac tissue. The system allows a physician to see a representation of the physical location of a catheter in a representation of an anatomic model of the patient's heart. The workstation is the primary interface with the physician. A servo catheter having pull wires and pull rings for guidance and a servo catheter control system are interfaced with the workstation. Servo catheter control software may run on the workstation. The servo catheter is coupled to an RF generator. The physician locates a site for ablation therapy and confirms the location of the catheter. Once the catheter is located at the desired ablation site, the physician activates the RF generator to deliver the therapy.

Abstract: An apparatus and method for use in performing ablation of organs and other tissues includes a radio frequency generator which provides a radio frequency signal to ablation electrodes. The power level of the radio frequency signal is determined based on the subject area of ablation. The radio frequency signal is coupled with the ablation electrodes through a transformation circuit. The transformation circuit includes a high impedance transformation circuit and a low impedance transformation circuit. The high or low impedance transformation circuit is selected based on the impedance of the ablation electrodes in contact with the subject tissue. Vacuum level, impedance level, resistance level, and time are measured during ablation. If these parameters exceed determinable limits the ablation procedure is terminated.

Abstract: An ablation system comprises a catheter including a pulse-echo ultrasonic transducer disposed in a distal portion and arranged to emit and receive an acoustic beam. The transducer emits and receives acoustic pulses to provide transducer detected information regarding the targeted tissue region being ablated. A rotation mechanism rotates at least the distal portion around a longitudinal axis of the catheter. A control and interface system processes the transducer detected information and provides feedback to a user via a user interface and/or the control and interface system to be used to control ablation. The transducer detected information includes a detected lesion depth along a beam emanation direction. The control and interface system includes a lesion depth correction module which converts the detected lesion depth along the beam direction to a corrected lesion depth in a normal direction which is perpendicular to the tissue surface in contact with the ablation element.

Abstract: The present invention involves systems and related methods for performing surgical procedures and assessments, including the use of neurophysiology-based monitoring to: (a) determine nerve proximity and nerve direction to surgical instruments employed in accessing a surgical target site; (b) assess the pathology (health or status) of a nerve or nerve root before, during, or after a surgical procedure; and/or (c) assess pedicle integrity before, during or after pedicle screw placement, all in an automated, easy to use, and easy to interpret fashion so as to provide a surgeon-driven system.

Abstract: A system for ablation with acoustic feedback comprises: a catheter which includes an elongated catheter body; at least one ablation element to ablate a targeted tissue region; and a pulse-echo ultrasonic transducer arranged to emit and receive an acoustic beam along a centroid in a beam direction, at a transducer beam angle of between about 30 degrees and about 60 degrees relative to a distal direction of the longitudinal axis at a location of intersection between the longitudinal axis and the beam direction of the centroid of the acoustic beam of the ultrasonic transducer, wherein the transducer transmits and receives acoustic pulses to provide lesion information in the targeted tissue region; an ablation power subsystem; an ultrasonic transmit and receive subsystem to operate the ultrasonic transducer; a control subsystem to control operation of the ablation power subsystem and the ultrasonic transmit and receive subsystem; and a display.

Abstract: A device for radio frequency ablation (RFA) of diseased tissue has a mesh or plate with a grid of holes for holding electrodes; a plurality of electrodes with adaptable active tip length; means for visualizing and probing insertion depth of each of the electrodes in the diseased tissue; a switch box, connectable to the electrodes and adapted to distribute current between the electrodes during the RFA process; a control unit for controlling the switch box; and means for monitoring the RFA process. The control unit is adapted to determine groups of electrodes, an electric mode for activation of each group of electrodes, a polarity for electrodes within each group of electrodes, an activation mode for the groups, a time interval and order for activation of the groups, a power output and current strength, and a duration of the RFA process.

Abstract: The invention provides a system and method for percutaneous energy delivery in an effective, manner using one or more probes. Additional variations of the system include array of probes configured to minimize the energy required to produce the desired effect.

Abstract: A method of making an incision in an organ includes piercing, by a puncture needle having a proximal end and a distal end, an abdominal wall and an organ that is to be incised, disposing, via the puncture needle, an electrode, to which a first end of a cable is electrically connected, inside the organ, and disposing a second end of the cable outside a body, performing insufflation using a conduit so as to form a space between the abdominal wall and the organ, pulling the cable farther from the second end so that the electrode is placed in contact with an incision position of the organ, and the incision position of the organ is pulled into the space, and supplying power to the cable so that an incision is made by the electrode at the incision position of the organ.

Abstract: Devices and methods for ablating a selected tissue volume, such as for ablating tumor, are disclosed. In certain embodiments, the ablation devices include a low-conductivity, tissue-piercing tip, an adjustment mechanism for selectively adjusting the length of an exposed portion of the electrode, for producing ablation volumes of desired geometry. In other embodiment, the methods allow the adjustment of the length of the exposed electrode portion be carried out by moving an insulative sleeve along the electrode.

Abstract: Method for the non-thermal treatment of human or animal tissue with high-voltage electrical discharge plasma is disclosed. The disclosed method employs current through plasma and through tissue not for the purpose of heating the tissue, but instead to maintain the plasma proximate to the tissue being treated. Also disclosed is a method of limiting the current through plasma and through tissue to minimize tissue heating by placement of an insulator or semiconductor between an electrode and tissue resulting in generation of a high-voltage discharge similar to a dielectric barrier discharge. The disclosed non-thermal plasma treatment can be employed to promote coagulation of blood, sterilization, disinfection, re-connection of tissue, and treatment of tissue disorders without causing significant thermal tissue damage.

Abstract: A method for a minimally invasive surgical system is disclosed including capturing camera images of a surgical site; generating a graphical user interface (GUI) including a first colored border portion in a first side and a second colored border in a second side opposite the first side; and overlaying the GUI onto the captured camera images of the surgical site for display on a display device of a surgeon console. The GUI provides information to a user regarding the first electrosurgical tool and the second tool in the surgical site that is concurrently displayed by the captured camera images. The first colored border portion in the GUI indicates that the first electrosurgical tool is controlled by a first master grip of the surgeon console and the second colored border portion indicates the tool type of the second tool controlled by a second master grip of the surgeon console.

Abstract: An apparatus for treating tissue within a lumen may include a therapeutic or diagnostic instrument. A cleaning device may also be supported by the instrument. The cleaning device has a portion of a cleaning surface positioned proximal to the distal end of the cleaning device.

Abstract: The invention provides a system and method for achieving the cosmetically beneficial effects of shrinking collagen tissue in the dermis or other areas of tissue in an effective, non-invasive manner using an array of electrodes. Systems described herein allow for improved treatment of tissue. Additional variations of the system include array of electrodes configured to minimize the energy required to produce the desired effect.

Abstract: Tissue may be cut and extracted from an interior location in a patient's body using a probe or tool which both effects cutting and causes vaporization of a liquid or other fluid to propel the cut tissue through an extraction lumen of the cutting device. The cutting may be achieved using an electrosurgical electrode assembly, including a first electrode on a cutting member and a second electrode within a cutting probe or tool. Thus, over a first cutting portion, radio frequency current may help cut the tissue and over a second or over transition region, the RF current may initiate vaporization of the fluid or other liquid to propel the tissue from the cutting device.

Abstract: An apparatus and method for use in performing ablation or coagulation of organs and other tissue includes a metallized fabric electrode array which is substantially absorbent and/or permeable to moisture and gases such as steam and conformable to the body cavity. The array includes conductive regions separated by insulated regions arranged to produce ablation to a predetermined depth. Following placement of the ablation device into contact with the tissue to be ablated, an RF generator is used to deliver RF energy to the conductive regions and to thereby induce current flow from the electrodes to tissue to be ablated. As the current heats the tissue, moisture (such as steam or liquid) leaves the tissue causing the tissue to dehydrate. Suction may be applied to facilitate moisture removal. The moisture permeability and/or absorbency of the electrode carrying member allows the moisture to leave the ablation site so as to prevent the moisture from providing a path of conductivity for the current.

Abstract: A portable electrosurgical system (100) for treating biological tissue with microwave radiation (e.g. having a frequency between 500 MHz and 60 GHz) is disclosed. The system comprises a hand-held microwave sub-assembly (102) which generates and amplifies a microwave signal (which may be continuous or modulated) for treatment and includes a treatment antenna (116) for delivering the radiation. Diode detectors (120, 122) in the sub-assembly (102) may detect forward and reflected power levels to enable determination of net delivered power. A dynamic impedance matching system may be provided to match energy developed by amplifiers (110, 112) in the sub-assembly (102) to the biological tissue load. A tuning filter (144) and couplers (146, 148, 150, 152) for extracting magnitude and phase information from the microwave signal are thus provided in the sub-assembly.

Abstract: A catheter and catheter system can use energy tailored for remodeling and/or removal of target material along a body lumen, often of thrombus from a blood vessel of a patient. An elongate flexible catheter body with a radially expandable structure may have a plurality of electrodes or other energy delivery surfaces. The electrode structures may be radially inwardly oriented and/or supported in cantilever to facilitate advancing the electrodes.

Abstract: The disclosure herein relates generally to immunotherapy and, more specifically, to the use of immunotherapy for treating tumors and pathogen infected tissues. The immunotherapy relates to first priming patients with allogeneic cells designed to be rejected by a Th1 mediated mechanism, then inducing in situ necrosis or apoptosis in a tumor or pathogen infected lesion. Necrosis or apoptosis can be induced by methods such as cryotherapy, irreversible electroporation, chemotherapy, radiation therapy, ultrasound therapy, ethanol chemoablation, microwave thermal ablation, radiofrequency energy or a combination thereof applied against at least a portion of the tumor or pathogen infected tissue. One or more doses of allogeneic cells (e.g., Th1 cells) are then delivered within or proximate to the tumor or pathogen-infected tissue in the primed patient. The present invention provides an immunotherapeutic strategy to develop de-novo systemic (adaptive) immunity to a tumor or pathogen.

Abstract: An endoscope treatment system includes: an endoscope; and a treatment tool that has a sheath that is inserted in a channel of an insertion portion of the endoscope, in which projection portions that project outward from the sheath in the radial direction are provided, and engagement portions that engage the projection portions are provided near the channel of the endoscope.

Abstract: A method for non-invasive treatment of cardiac arrhythmias is provided. The method includes acquiring body surface electrical signals at locations on a body surface of a living being from electrodes placed on locations of the body surface, reconstructing three-dimensional heart and torso anatomical models of the living being from an imaging scan, and calculating an electrical activity a throughout three-dimensional volume of the heart by electrocardiogram inverse problem solving based at least in part on the acquired body surface electrical signals and the reconstructed three-dimensional heart and torso anatomical models. The method also includes identifying at least one location of at least one site of origin of a cardiac arrhythmia according to the calculated electrical activity within the heart, and delivering focused energy to the identified at least one location of the at least one site of origin of the cardiac arrhythmia.

Abstract: A method for tissue ablation is described. An RF applicator including an electrode carrier with one or more bipolar electrodes thereon is positioned at a target tissue site for tissue ablation. A current at an initial current level is passed through the one or more bipolar electrodes to the target tissue site to apply an initial power density to destroy tissue for an initial time period. A vacuum source in fluid communication with the RF applicator is employed to remove moisture generated during ablation away from the target tissue site. After the initial time period, the power density is ramped up by increasing the current passed through the one or more bipolar electrodes to the target tissue site for a second time period.

Abstract: The invention relates to a device for the implantation of occlusion helixes (3) that can be separated by electrolysis in blood vessels and body cavities, especially aneurysms (12), said device comprising an insertion aid (4), at least one occlusion helix (3) that is distally arranged in relation to the insertion aid (4) and at least one electrolytically corrodible severance element (2), with at least one stabilization helix (5) being arranged between severance element (2) and occlusion helix (3) and said stabilization helix (5) being connected with the occlusion helix (3) by an electrically isolating adhesion layer (7) such that the occlusion helix (3) becomes isolated from the voltage when an electrical voltage is applied to the severance element (2).

Abstract: An electrosurgical system is disclosed comprising a generator configured to electrosurgical coagulation waveforms. The generator includes a closed loop control system for controlling the electrosurgical coagulation waveforms. The closed loop control system includes a sensor configured to sense a tissue property and/or an energy property and to transmit the tissue property and/or the energy property as one or more sensor signals having an amplitude. The control system also includes a gain controller configured to process the at least one sensor signal to reduce the amplitude of the sensor signals and to obtain a signal to noise ratio of the at sensor signals within a predetermine range. A microprocessor coupled to the generator and is configured to adjust the electrosurgical coagulation waveforms as a function of the sensor signals.

Abstract: An endoscopically-guided intra-abdominal fat aspiration system for performing fat aspiration operations, including an endoscopy subsystem for capturing and recording captured digital video images of the intra-abdominal region of a patient, and a twin-cannula powered fat aspiration subsystem having a powered hand-supportable fat aspiration instrument provided with a bipolar electro-cauterizing twin-cannula assembly.

Abstract: A system and method for detecting faults within an electrosurgical instrument having a shield and an active electrode uses multiple possible fault conditions. In one embodiment the monitoring system comprises an electrosurgical generator coupled to the electrosurgical instrument and adapted to deliver power to the active electrode of the electrosurgical instrument, monitoring circuitry coupled to the electrosurgical generator and the electrosurgical instrument, wherein the monitoring circuitry comprises an active electrode voltage sensor an active electrode current sensor and a shield current sensor. The monitoring circuitry measures at least two of the active voltage, the active or return electrode current, and the shield current.

Abstract: Devices and methods provide for ablation of cardiac tissue for treating cardiac arrhythmias such as atrial fibrillation. Although the devices and methods are often be used to ablate epicardial tissue in the vicinity of at least one pulmonary vein, various embodiments may be used to ablate other cardiac tissues in other locations on a heart. Devices generally include at least one tissue contacting member for contacting epicardial tissue and securing the ablation device to the epicardial tissue, and at least one ablation member for ablating the tissue. Various embodiments include features, such as suction apertures, which enable the device to attach to the epicardial surface with sufficient strength to allow the tissue to be stabilized via the device. For example, some embodiments may be used to stabilize a beating heart to enable a beating heart ablation procedure. Many of the devices may be introduced into a patient via minimally invasive introducer devices and the like.

Abstract: A surgical instrument, such as an endoscopic or laparoscopic instrument, includes an ablation device. The ablation device includes an elongate relatively flexible member having a proximal end and a distal end, the flexible member includes at least a first working channel. A first and second electrode extends from a working channel at the distal end of the flexible member. The first and second electrodes are adapted to be endoscopically located in a tissue treatment region. The first and second electrodes are adapted to couple to an electrical waveform generator to receive an irreversible electroporation electrical waveform sufficient to ablate tissue located between the first and second electrodes. The waveform parameters of the irreversible electroporation electrical waveform are determined based on image information received from the tissue treatment region.

Abstract: An ablation catheter is provided for ablating internal tissue of a patient. The catheter includes a distal end that is adapted to be inserted into a body cavity relative to a desired location therein (e.g., within the heart). An ablation electrode is connected relative to the distal end of the catheter for providing ablation energy to patient tissue. A heat sink is provided that is in thermal contact with the ablation electrode. The heat sink, in addition to being in thermal contact with the ablation electrode, is electrically isolated from the ablation electrode. This allows the heat sink to conduct heat away from the ablation electrode without dissipating electrical energy from the electrode. In this regard, the heat sink may prevent build-up of excess heat within the electrode that may result in blood coagulation and/or tissue charring.

Abstract: An electrosurgical system and method for treating hard and soft tissues in the body comprises a shaft, a distal end section, an active electrode associated with the distal end section, a first fluid supply adapted to deliver a first electrically conductive fluid to the target site, and a second fluid supply adapted to deliver a second electrically conductive fluid to the active electrode. The system is adapted to treat a wide variety of hard tissues such as, for example, bones, calcified structures, calcified deposits, teeth, plaque, kidney-stones, gall-stones and other types of tissue by generating plasma in the vicinity of the active electrode, and applying the plasma to the tissue or structures.

Abstract: Devices and methods are provided for the ablation of regions of the digestive tract to achieve hemostasis and to eradicate chronically bleeding lesions as occur with gastric antral vascular ectasia (GAVE), portal hypertensive gastropathy (PHG), radiation proctopathy and colopathy, arteriovenous malformations, and angiodysplasia. Ablation is typically provided in a wide-field manner, and in conjunction with sufficient pressure to achieve coaptive coagulation. Ablation, as provided the invention, starts at the mucosa and penetrates deeper into the gastrointestinal wall in a controlled manner. Ablation control may be exerted by way of electrode design and size, energy density, power density, number of applications, pattern of applications, and pressure. Control may also be provided by a fractional ablation that ablates some tissue within a target region and leaves a portion substantially unaffected.