Abstract: Biological tissue is sealed or fused to occlude an opening by compressing apposite sidewall portions of the tissue and applying sufficient energy to cause the fibers of the compressed apposed sidewall portions to intertwine and fuse with one another to form a permanent seal. The energy application is controlled by detecting a precursor fusion condition while applying the energy and before sufficient energy has been applied to achieve a permanent seal. The application of energy is terminated in a time-delayed relationship to the detection of the precursor fusion condition. The precursor fusion condition is detected from derivative values of the total accumulated amount of high-frequency energy conducted through the tissue.

Abstract: A high-frequency incision tool for endoscope comprises a sheath inserted through and extracted from a treatment tool guide lumen of an endoscope; an operation unit connected to the rear of the sheath; a pair of electrode blades disposed in parallel and oriented forward at the front position of the sheath, the pair of electrode blades opening forward and closing back through remote manipulation of the operation unit; and a planar portion provided at the tip of at least one of the electrode blades, the planar portion having a projected area, when viewed from the front, larger than the cross sectional areas of the electrode blades at a portion close to their front ends.

Abstract: Low temperature lesion formation apparatus, systems and methods. The apparatus includes a base member and an inflatable element carried by the base member.

Abstract: An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.

Abstract: A cautery catheter is described having an expandable and electrically conductive mesh that can cauterize treatment sites having large effective surface areas. The mesh is composed of interwoven filaments which are aligned with the cautery catheter in an unexpanded state. Reorientation of the filaments of the mesh enables expansion of the mesh. When the expanded mesh contacts the desired treatment area, an electrocautery unit supplies electrical energy to the filaments of expanded mesh to cauterize the treatment site.

Abstract: RF power is applied to a circular RF electrode cutting a side opening in a graft material of a main stent-graft in situ. As the side opening is formed by the applied RF power and the associated plasma discharge, the side opening is formed with a minimal application of force to the graft material. Further, the side opening is circular and has a fused edge.

Abstract: The present invention is directed to ablation devices and methods utilizing pressure sensitive conductive composites, such as quantum tunneling composites, or other contact-sensitive, conductive polymers. The materials provide for electrodes and methods capable of differentiating between a soft and a hard push. The present invention thus provides an electrode for delivering selective electrical energy for ablation that may be varied based upon the pressure exerted on the surface area of the targeted tissue.

Abstract: A novel surgical clamp having a pair of jaws, which may be used to ablate or create leisons in tissue. In embodiment, the jaws have an articulated position wherein the jaws are separated and not parallel to one another, an opened position wherein the jaws are separated and substantially parallel to one another, and a closed position wherein the jaws are adjacent and substantially parallel to one another. One or more of the jaws can articulate independent of the other jaw. Other embodiments are described in the attached specification.

Abstract: A catheter includes a cryoablation tip with an electrically-driven ablation assembly for heating tissue. The cryoablation tip may be implemented with a cooling chamber through which a controllably injected coolant circulates to lower the tip temperature, and having an RF electrode at its distal end. The RF electrode may be operated to warm cryogenically-cooled tissue, or the coolant may be controlled to conductively cool the tissue in coordination with an RF treatment regimen, allowing greater versatility of operation and enhancing the lesion size, speed or placement of multi-lesion treatment or single lesion re-treatment cycles.

Abstract: A cryosurgical system featuring both cooling and heating utilizing a single type of cryogen but from two different sources. The liquid cryogen cools the tip of a cryosurgical instrument in the cryosurgical system, such as a cryoprobe or cryocatheter. The gaseous cryogen is further heated by a heating element, preferably an electrical heating element, supplying the heating needed for the thaw and release parts of the cryo treatment procedure. Thus, the cryosurgical system supports the freeze/thaw cycle of the operation of the cryosurgical instrument.

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: Monitoring intracardiac ablation progress in near real time is accomplished by evaluating capture of a pacing signal while ablation energy is concurrently directed to a target site. Sufficiency of ablation is indicated by failure of signal capture at a maximum predetermined pacing voltage. A common electrode in a cardiac catheter is simultaneously used to test pacing capture and to deliver ablation energy.

Abstract: The present invention provides an ablation catheter tip for use with an irrigated catheter device comprising an inner cavity and at least one passageway that leads to an orifice, wherein the fluid flow from the orifice promotes a circular, vortex, or spiral flow around the catheter tip from the acute angle formed at the orifice with respect to a line tangent to the surface of the ablation electrode at the orifice. The present invention further provides for an ablation catheter tip, for use with an irrigated catheter device, comprising an inner cavity and at least one curved passageway that leads to an orifice, wherein a line drawn tangent to the arc of the curve forms an acute angle measured with respect to a line drawn tangent to surface of the ablation electrode at the orifice of the passageway.

Abstract: A disposable open electrosurgical forceps for sealing tissue is disclosed in the present disclosure. The disposable open electrosurgical forceps comprise a pair of first and second shaft members containing a fiber reinforced thermoplastic blend material having fiber strands of at least 2 millimeters in length. Each shaft member includes a jaw member disposed at a distal end thereof which are movable from a first position in spaced relation relative to one another to at least one subsequent position wherein the jaw members cooperate to grasp tissue therebetween. Each of the jaw members also includes an electrically conductive sealing plate for communicating electrosurgical energy through tissue held therebetween. At least one of the jaw members includes a knife channel defined along a length thereof which is dimensioned to reciprocate a cutting mechanism therealong.

Abstract: A monopolar electrosurgical return electrode to prevent unwanted thermal effects in monopolar electrosurgery, accomplished in one aspect by volumetric incorporation of temperature-resistive material of positive nature into a flexible and adhesive return electrode pad is provided. The incorporation of positive temperature coefficient resistance with low resistance at room temperature will increase the local electrical resistance of the pad with an increase of the local return electrode temperature corresponding to a switching of the resistance from low to high value which in turn will lead to a reduction of the local current density. The switching temperature of the positive temperature coefficient return electrode is low enough to prevent significant thermal heating of the patient's tissue.

Abstract: A debrider apparatus is disclosed. The debrider includes a first tubular member that is adapted to connect to a first potential of an electrosurgical generator. A second tubular member is at least partially disposed within the first tubular member and is adapted to connect to a second potential of the electrosurgical generator. At least one tubular member is selectively movable relative to the other. A first set of teeth is disposed around at least a portion of a distal periphery of the first tubular member. A second set of teeth is disposed around at least a portion of a distal periphery of the second tubular member. At least one switch is operably coupled to at least one of the tubular members and activates movement of one tubular member and supplies respective electrical potentials to the tubular members.

Abstract: Medical treatment device with an ablation catheter and a visualization device for joint display of the ablation catheter and the anatomy of a part of a patient's body to be treated, whereby the visualization device is embodied for detection of areas of risk of the part of the body to be treated and for displaying the areas of risk jointly with the ablation catheter and the anatomy.

Abstract: A surgical instrument for delivering energy to lung tissue, for example to cause lung volume reduction. In one embodiment, an elongated catheter has a handle portion that includes an interior chamber that is supplied with a biocompatible liquid media under pressure. An energy source delivers energy to the media to cause a liquid-to-vapor phase change within the interior chamber and ejects a flow of vapor media from the working end of the catheter. The delivery of energy and the flow of vapor are controlled by a computer controller to cause a selected pressure and selected volume of vapor to propagate to the extremities of the airways. Contemporaneously, the vapor undergoes a vapor-to-liquid phase transition which delivers a large amount of energy to airway tissue. The thermal energy delivered is equivalent to the heat of vaporization of the fluid media, which shrinks and collapses the treated airways.

Abstract: An electrosurgical system comprising, among other things, a control console to which detachably connects one or more electrosurgical probes capable of coagulating and ablating tissue. The control console generates a selectively variable power signal having a duty cycle that is dynamically modulated so as to maintain an average power level of a probe that is lower than a predefined maximum power level. The system can also incorporate both an impedance monitoring system and a current monitoring system as means to detect potentially dangerous situations, as well as a monitoring system for detecting impedance at relatively low power levels upon first activation of the probe. The probe can also incorporate non-volatile memory for storing probe-specific operating parameter data, probe usage data, data restricting probe use, error codes, and control console updates.

Abstract: A catheter assembly for pressure-sensitive control of ablation treatment is disclosed. The assembly includes a conductive element, an electrode, and a pressure sensitive conductive composite member positioned between the conductive element and the electrode. At least one of the conductive pin, the pressure sensitive conductive composite element and the ablation electrode are moveable to create an engagement position and a non-engagement position. In the engagement position, the elements are electrically coupled such that ablation energy may be delivered from the conductive pin to the ablation electrode via the pressure sensitive conductive composite element. In the non-engagement position, the elements are electrically decoupled such that ablation energy is not delivered to the ablation electrode. A related method for pressure-sensitive control of ablation is also disclosed.