Abstract: A method and apparatus for transmural ablation using an instrument containing two electrodes or cryogenic probes. A clamping force is exerted on the two electrodes or probes such that the tissue of the hollow organ is clamped therebetween. Bipolar RF energy is then applied between the two electrodes, or the probes are cryogenically cooled, thus ablating the tissue therebetween. The method provides for ablating cardiac tissue of a patient utilizing a sub-xyphoid approach and identifying cardiac tissue prior to ablation.

Abstract: An electrosurgical apparatus comprises a high frequency generator (1) with an associated power control system, a handpiece (2) with means for removably mounting an electrode (5) therein, and a connection cable (3) between an output (4) of the generator and the handpiece. The transfer characteristic of the system provides a substantially true ohmic transfer of loads on the electrode side of the connection cable (3) to the generator side thereof at or around a predetermined load on the electrode. In order to achieve a fully automatic and optimalized control af power supplied from a cutting electrode, whereby the control is instantly responding, to changes in the electrode load, the electrosurgical apparatus is characterized in that the power control system comprises a driver stage (7) followed by a reflectormeter (9) adapted and arranged to sense the generator output (4).

Abstract: The variable stiffness heating catheter includes a heating catheter shaft including at least one electrically conductive member, a reinforcing tube with apertures formed around the surface of the reinforcing tube, and at least one coaxial outer layer of a polymer, metal, or both for providing desired variations in stiffness along at least a portion of the length of the shaft. The apertures can be formed as axial or helical slits in the surface of the reinforcing tube, and the reinforcing tube can also be formed to be tapered at the point where the apertures are formed in the reinforcing tube to provide a heating catheter that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.

Abstract: A multiple RF return pad contact detection system is provided which is adaptive to different physiological characteristics of patients without being susceptible to electrosurgical current interference (e.g., interference or measurement interaction between components of the detection system). The detection system can measure or sense the contact resistance or impedance between the patient and pairs of RF return pads or return electrodes where multiple pairs of RF return pads are utilized due to the high current frequently needed during electrosurgery while eliminating or minimizing the risk of measurement interaction between the RF return pad pairs. The system allows for the independent and simultaneous measurement of the pad contact impedance for each pair of RF return pads. If the impedance of any pad pair is above a predetermined limit, the system turns off or reduces the electrosurgical output of the electrosurgical generator to prevent excess heating.

Abstract: An excisional biopsy method is disclosed. The method can include rotating an arcuate shaped electrode around a tissue specimen, and drawing a sheath around the tissue specimen as the specimen is cut from a tissue mass. In one embodiment, the method includes tunneling to a tissue site with one electrode, and cutting with a second electrode to obtain the tissue specimen.

Abstract: Electrosurgical apparatus and methods for ablating, coagulating, shrinking, stiffening, or other treatment of a target tissue of a patient. An apparatus of the invention includes an electrosurgical probe, and an introducer needle adapted for passing the distal end of the probe therethrough, wherein the probe includes an uninsulated shaft which makes electrical contact with the introducer needle when the shaft is engaged within a lumen of the introducer needle. The apparatus further includes an active electrode and a return electrode, wherein the return electrode comprises the shaft in combination with the introducer needle. In one embodiment, the active electrode includes an expandable electrode head.

Abstract: The present invention provides systems, apparatus, and methods for dissecting, resecting, severing, cutting, contracting, coagulating, or otherwise modifying a tissue or organ of a patient. An apparatus of the invention includes an electrosurgical probe configurable between an open configuration and a closed configuration, the probe including an active electrode terminal, a fixed return electrode disposed proximal to the active electrode terminal, and a movable return electrode configured to move linearly with respect to the active electrode terminal between the open configuration and the closed configuration. A method of the present invention comprises clamping a blood vessel between the active electrode terminal and the movable return electrode, coagulating the clamped blood vessel by application of a first high frequency voltage, and severing the coagulated blood vessel by application of a second high frequency voltage.

Abstract: A system, method and/or apparatus is provided for visualization or imaging of the transverse carpal ligament and surrounding structures/features of a hand of a patient, and treatment of the transverse carpal ligament, particularly, but not necessarily, for performing non-invasive carpal tunnel release. The subject invention utilizes ultrasound waves preferably, but not necessarily, in the high frequency range and cavitations to image the transverse carpal ligament (TCL), record its location in three-dimensional space, and perform precision treatment on the transverse carpal ligament. Treatment may range from stretching or lengthening the TCL to complete tissue ablation or dissection of a portion or portions of the TCL (as is performed in a standard carpal tunnel release procedure) in order to release pressure within the carpal tunnel. Particularly, high temperature conditions are generated at target tissue of the TCL resulting in elongation or necrosis/dissection.

Abstract: Method and devices for electrosurgery by means of oxy-hydro combustion. Deleterious effects to tissue are minimized by means of control of acid-base shift reactions, which reactions can further be employed to control oxy-hydro combustion reactions. In one embodiment, radiofrequency energy in electrical connection with electrodes is employed to induce electrolysis in an aqueous salt environment, thereby producing oxygen and hydrogen, with the same energy source employed to initiate a combustion reaction.

Abstract: The present invention features a device having a barrier membrane contacting surface, the device containing: a power source; a first conductive electrode; a second conductive electrode; and a carrier; wherein the power source is in electric communication with the first conductive electrode and the second conductive electrode, wherein the first conductive electrode and the second conductive electrode are in ionic communication with the carrier, and wherein the carrier is in communication with the barrier membrane contacting surface.

Abstract: A method and system for treating a vulnerable plaque associated with a blood vessel of a patient is disclosed. The method includes rupturing a fibrous cap of the vulnerable plaque. A portion of liquid contents of the vulnerable plaque are released into a blood vessel lumen as a result of the fibrous cap rupture. The method further includes capturing at least one of any emboli present within the blood vessel as a result of the fibrous cap rupture. The system includes a rupture device that ruptures a fibrous cap of the vulnerable plaque and a capture device that captures at lest one embolus within the blood vessel.

Abstract: Methods and devices for occlusion of the fallopian tubes of a woman. The method involves thermally damaging the lining of the utero-tubal junction with relatively low power, followed by placement of a reticulated foam plug. In one embodiment, vascularized tissue grows into the plug and prevents or discourages formation of scar tissue around the plug. Another embodiment with a relatively small foam pore size encourages formation of a vascularized capsule around the plug. The presence of this vascularized capsule limits the patient's foreign body response, so that the capsule does not constrict around the plug. Also presented is a catheter designed for wounding the epithelial layer of the utero-tubal junction, and a method of using the catheter to form a long yet shallow lesion in the utero-tubal junction.

Abstract: The invention provides apparatus and methods for ablating tissue and is particularly useful for creating lesions in the heart wall for the treatment of atrial fibrillation. The apparatus has a suction well which is adhered to the tissue to be ablated. The ablating element is surrounded by the suction well. A fluid is delivered to the ablating element to conduct RF energy to the tissue and/or to cool the tissue. The device is preferably formed with a number of cells with each cell having a suction well and at least one ablating element. The device also preferably has a locking mechanism for locking one part of the device to another part of the device to form a closed loop for ablating around structures such as the pulmonary veins.

Abstract: An arterial closure device for use following coronary catherization procedures to close arterial access openings through the arterial wall while permitting post operative flow through the artery includes a housing having proximal and distal ends, and defining a longitudinal axis, first and second arterial tissue everting members mounted adjacent the distal end of the housing and first and second jaw members mounted adjacent the first and second tissue engaging members. The first and second arterial tissue everting members are dimensioned for at least partial positioning within the arterial access opening in the arterial wall and are deployable in at least a radial outward direction relative to the longitudinal axis of the housing to engage respective opposed arterial tissue portions on opposed sides of the opening and move the tissue arterial portions to an everted condition thereof.

Abstract: An electrosurgical instrument includes a housing having a shaft attached thereto which connects a pair of first and second jaw members such that the jaw members are movable relative to one another to grasp tissue therebetween. The instrument also includes a four-bar handle assembly attached to the housing for actuating a drive rod assembly. The handle assembly includes a handle and a cam-like piston which cooperate to impart a uniform closure pressure against tissue grasped between the jaw members. The instrument also includes a rotating assembly for rotating the jaw members, a knife assembly for separating tissue and a pair of electrical leads connect the jaw members to a source of electrical energy. The electrical leads include slack loops disposed in the rotating assembly which permit rotation of the jaw members about the axis.

Abstract: An internal indifferent electrode device including a flexible shaft, an energy transmission device adapted to be inserted into the body supported on the shaft, and a connector adapted to mate with the power return connector of a power supply apparatus.

Abstract: A method of electroforming tissue comprises creating stress in the tissue; and causing a direct current to flow in the tissue to change the stress, strain, or intrinsic mechanical properties including shape of the tissue. Force is mechanically applied to the tissue to create external stresses or material parameters of the tissue are used to create internal stresses in the tissue by causing a current to flow in the tissue. The method further comprises the step of monitoring the stresses in the tissue and controlling the current flowing in the tissue according to the stresses therein by monitoring impedance, the optical properties, the pH, acoustic properties of the tissue, the gas formation in the tissue, the color of the tissue as caused by a chemical dye disposed therein or as caused by electroplating a material thereon.

Abstract: Methods, devices and systems for treating patent foramen ovale (PFO) involve advancing a catheter device to a position in a heart for treating a PFO, bringing tissues adjacent the PFO at least partially together, and applying energy to the tissues to substantially close the PFO acutely. Catheter devices generally include an elongate catheter body, at least one tissue apposition member at or near the distal end for bringing the tissues together, and at least one energy transmission member at or near the distal end for applying energy to the tissues. In some embodiments, the tissue apposition member(s) also act as the energy transmission member(s). Applied energy may be monoploar or bipolar radiofrequency energy or any other suitable energy, such as laser, microwave, ultrasound, resistive heating or the like.

Abstract: In radiofrequency ablation, larger lesion volumes are obtained for a given energy delivery by energizing at least two electrodes on either side of the tumor so that current is focused between them rather than dispersed radially to a large area ground plate. Modified standard umbrella probes may be used or a specialized dual electrode array may be fabricated for simplified use. Differential impedance between tumor and non-tumor tissues at certain frequencies is exploited to further improve lesion shape and size.

Abstract: An electrode arrangement is provided having at least one electrode for insertion into a human or animal body for electrothermal treatment of the body. The electrode is situated on an electrode support and is connected to an alternating current source via a supply lead and to a temperature stabilizer device for influencing the effective temperature profile in a treatment area. The electrode support and the electrode, or electrodes, are constructed for direct insertion into body tissue, said insertion being channel forming. The temperature stabilizer device has a timed heating device.

Abstract: A method of preparing and ablating heart tissue includes a pre-treatment step of delivering a jet of conductive fluid to a portion of heart tissue. The conductive fluid is delivered using an injection device such as a hand-held jet injector, probe, or catheter. After injecting the heart tissue with the conductive fluid, RF energy is delivered to the site of the injection to form a lesion. The method enables a physician to produce large and accurately placed lesions within the treated tissue.

Abstract: Methods and devices for forming a lesion in a target tissue having a cavity within. A first RF electrode and a second RF electrode can be coupled to opposite poles of an RF current source. The second electrode can be inserted into the tissue cavity and expanded to contact the target tissue from within. The first electrode can be externally disposed against the target tissue while applying RF current between the first and second electrodes to ablate the target tissue. Some methods are directed to ablating tribiculated atrial wall tissue to treat atrial fibrillation. The second electrode can contact the tribiculated tissue directly from within to provide a direct path between the two electrodes. In some methods, the second electrode is inserted through an incision made to remove an atrial appendage. The methods can provide deeper, narrower lesions relative to those made using remote, indifferent electrodes.

Abstract: Surgical instruments and procedures promote placement of a tissue-ablating probe surrounding the left and right pulmonary veins within the intrapericardial space of a patient's heart via access through a subxiphoid or subcostal entry incision. An opening is formed in the pericardium near the apex region of the heart to facilitate formation of openings through three pericardial reflections by which a tissue-ablating probe is positioned around the pulmonary veins.

Abstract: The invention provides a transurethral ablation device comprising a catheter sized for insertion into a urethra of a male patient. A distal end of the catheter defines a lateral cavity. A vacuum line applies vacuum pressure to the cavity to capture a portion of the urethra and a portion of the prostate into the cavity. An ablation probe has a distal tip mounted within the catheter adjacent the cavity, and is movable for insertion into the captured portion of the prostate. The ablation probe can be inserted with an orientation substantially parallel to the urethral wall. Alternatively, multiple ablation probes can be provided for simultaneous use in ablating tissue with a target site in the prostate. A suction cannula may be used to remove ablated tissue from the target site.

Abstract: The invention provides methods and devices for ablation of stomach tissue to treat obesity. For example, the invention may involve ablation of mucosal tissue to inhibit ghrelin production, recognized as a root cause of increased appetite. The invention alternatively may involve ablation of sub-mucosal tissue to alter myoelectric activity and thereby induce gastroparesis. As a further alternative, gastric muscle tissue, vagal nerves within the stomach or the pyloric region may be ablated to alter stomach function and thereby induce gastroparesis.

Abstract: A method for treating pelvic tumors, such as uterine leiomyomata, includes inserting an ablation apparatus into a pelvic region and positioning the ablation apparatus either proximate or into a pelvic tumor. The method further includes using a laparoscope and an imaging device, such as an ultrasound machine, to confirm the location of the pelvic tumor and placement of the ablation apparatus. Various ablation apparatuses may be used, including those with multiple needles or deployable arms that are inserted into the pelvic tumor and those without arms. The method further includes delivering electromagnetic energy or other energy through the ablation apparatus to the pelvic tumor to ablate the tumor. A surgical system for ablating pelvic tumors is also provided.

Abstract: In general, the invention provides a transurethral ablation device comprising a fluid delivery port for delivery of a fluid, such as a gel, liquid, or liquid suspension, to a tissue site targeted for ablation. The fluid is electrically conductive and carries a local anesthetic agent. When the fluid is delivered, it provides an anesthetic effect in the target tissue site, alleviating pain associated with the ablation procedure. In addition, the fluid is loaded with electrically conductive material to enhance conductivity and permit the creation of a virtual electrode. The virtual electrode extends throughout the volume of fluid delivered to the target tissue site, and enhances the volumetric coverage and precision of the ablation procedure with the prostate tissue.

Abstract: This is directed to improving the gaseous exchange in a lung of an individual and particularly, this is directed to improving the gaseous exchange in individuals having chronic obstructive pulmonary disease. It generally includes fluidly connecting the lung to an extrapleural airway such as the trachea. In one variation, a conduit is deployed to place the lung and the trachea in fluid communication which allows trapped oxygen-reduced air to pass directly out of the lung and into the trachea. Removing nonfunctional air from the lung tends to improve the gaseous exchange of oxygen into the blood and decompress hyper-inflated lungs. Sealant and biocompatible adhesives may be provided on the exterior of the conduit to prevent side flow, leaks and to otherwise prevent air from entering spaces not intended to receive air such as the pleura space.

Abstract: The present invention provides methods, systems, and kits for protecting body tissues which are adjacent to tissues undergoing thermal treatment. The methods, systems, and kits are useful for thermally ablating tumors which lie at or near the surface of an organ, such as the kidney, pancreas, stomach, spleen, and particularly the liver. In radiofrequency and electrosurgical treatment, electrodes may penetrate and heat may dissipate into surrounding tissues and into tissue adjacent to the target organ, thus causing unwanted tissue damage. These risks and others may be lessened or avoided with the use of an interface shield between the target region and adjacent body tissues to shield surrounding organs and tissue from treatment effects.

Abstract: An ECG-prep scan is used to set an optimum time phase in both systole and diastole of the heart. At each of the different time phases, an imaging scan is started to acquire a plurality of sets of echo data. An artery/vein visually separated blood flow image is produced from the echo data. The imaging scan uses a half-Fourier technique, for example. This provides high-quality blood flow images with shorter scan time, without injecting a contrast medium. Additionally, with a readout gradient pulse applied substantially parallel with a direction of slowly flowing blood, a scan is performed in synchronism with an optimally determined cardiac time phase. The readout gradient pulse has a dephasing pulse for enhancing differences in a flow void effect depending on blood flow velocities. This enables slow-speed flows, such as blood flows in the inferior limb, to be depicted without fail.

Abstract: The invention relates to one or more catheterization methods of altering conduction properties along pathways in the heart, and in vessels in conductive communication with the heart, and is particularly related to methods of ablative catheter treatment of atrial fibrillation and arrhythmias of accessory pathways.

Abstract: Methods and apparatus for treatment of patent foramen ovale (PFO) provide for applying energy to tissues adjacent the PFO with a catheter device to substantially close the PFO acutely. Apparatus generally includes a catheter device having at least one energy transmission member at or near its distal end configured to apply energy to PFO tissues to acutely, substantially close the PFO. Applied energy may be monoploar or bipolar radiofrequency energy or any other suitable energy, such as laser, microwave, ultrasound, resistive heating or the like. Some embodiments of a catheter device further include one or more tissue apposition members near the distal end for helping bring PFO tissues together, such as a PFO covering member, a vacuum applying member and/or the like. PFO closure via energy-based approaches of the invention may help prevent stroke, treat migraine headache, and possibly treat or prevent other medical conditions.

Abstract: The present invention relates to a devices and methods for their use for the release of medical workpieces such as, without limitation, embolic devices, from apparatuses used to deliver them to a target site in a patient's body involving use of a piezoelectric member that is fracturable and/or an adhesive layer that is susceptible to adhesive or cohesive failure.

Abstract: Apparatus for sealing vascular penetrations comprise a shaft having an electrode or other energy-applying element at a distal end. The shaft is placed in a tissue tract over a blood vessel penetration and located using a locator which engages an inner wall of the blood vessel. Once in position, an anchor is used to hold the shaft, allowing the locator to be removed. Energy is then applied through a distal tip of the shaft in order to induce desiccation and plug formation in a blood pool formed between the distal end of the shaft and the wall of the blood vessel.

Abstract: A surgical method and apparatus for positioning a diagnostic or therapeutic element within the body. The apparatus may be catheter-based or a probe including a relatively short shaft.

Abstract: A method for electrosurgically sealing a tissue includes steps of: (A) applying a first pulse of RF energy to the tissue; and (B) applying at least one subsequent RF energy pulse to the tissue and varying RF energy parameters of individual pulses of subsequent RF energy pulses in accordance with at least one characteristic of an electrical transient that occurs during the individual pulses of the subsequent RF energy pulses. The method terminates the generation of subsequent RF pulses upon a determination that the electrical transient has passed a predetermined limit.

Abstract: A plasma tool adapted to emit high quantum energy inert gas atoms in a stream for cutting, liquefying, or evaporating material such as human tissue during surgical procedures. The apparatus comprises a source of inert gas, a plasma cell in communication with the inert gas source for imparting energy to the inert gas atoms and defined in part by a positive electrode and a negative electrode, at least one power supply electrically connected between the positive and negative electrodes, and means for directing the high quantum energy inert gas atoms at a target. The power supply initially provides an ionization voltage between the negative and positive electrodes to initiate a plasma from the inert gas in the plasma cell, and subsequently provides a pulsed voltage curve to sustain the plasma at a predetermined energy level. Methods for using the tool, including for performing surgical procedures, are also described.

Abstract: A system and method for surface tissue ablation on the patient's outer skin, such as the epidermis or the underlying dermis. An electrosurgical probe 130) comprises a shaft 132) having an array of active electrodes 136) on its distal tip and a connector 134) at its proximal end for coupling the electrode array to a high frequency power supply. An electrically conducting liquid is directed along a fluid flow path 142) past a return electrode surface 138) to the target site to provide a current flow path between the target site and the return electrode. High frequency voltage is then applied to the active and return electrodes so that an electric current flows from the active electrode, through a layer of vapor formed at the tip of the electrode, and to the return electrode through the current flow path provided by the electrically conducting liquid.

Abstract: Systems, apparatus, and methods for treating spinal tissue and other body structures in open and endoscopic spine surgery to relieve symptoms, such as neck or back pain. In particular, the present invention provides methods for the controlled heating of various tissues in or around the vertebral column, including various interspinous tissues, such that spinal ligaments and cartilage surrounding the vertebrae and the facet joints are shrunk or tightened to stabilize the vertebral column of a patient. Thermal energy is applied to the target tissue in a subablation mode of an electrosurgical system to cause shrinkage of the tissue, thereby stiffening the interspinous tissue and stabilizing the vertebral column. In an exemplary embodiment, a high frequency RF voltage can be applied between one or more active electrode(s) and one or more return electrode(s) to heat a target interspinous tissue to within a temperature range at which irreversible shrinkage of the tissue occurs.

Abstract: Methods and apparatus are provided for an achieving low-rate collagen shrinkage using an electrode array comprising an elongated insulator strip having at least one pair of spaced-apart bi-polar RF electrodes, and a “channeling” disposed on the strip between the bi-polar electrodes to direct the flow of RF current therebetween. The channeling electrode is not directly coupled to the RF power source, but only indirectly through the tissue in contact with the channeling electrode. The apparatus enables low RF power levels (e.g., 0.5 watts to 25 watts) to be applied over time intervals of 5 seconds to 180 seconds to attain low-rate collagen shrinkage by directing or focusing the path of the RF current.

Abstract: An irrigation ablation probe comprises a generally rigid probe body and a handle mounted to the proximal end of the probe body. The generally rigid probe body comprises an ablation electrode at its distal end having at least one irrigation opening through which fluid can pass. An infusion tube extends through the probe body for introducing fluid into the ablation electrode. The irrigation ablation probe is useful for treating atrial fibrillation during open heart surgery.

Abstract: An irrigation ablation probe comprises a generally rigid probe body and a handle mounted to the proximal end of the probe body. The generally rigid probe body comprises an ablation electrode at its distal end having at least one irrigation opening through which fluid can pass. An infusion tube extends through the probe body for introducing fluid into the ablation electrode. The irrigation ablation probe is useful for treating atrial fibrillation during open heart surgery.

Abstract: An electrocautery device is disclosed. In accordance with one aspect of the invention, the electrocautery electrode/tip is provided with a hollow, conductive tube terminating at its distal end in a ball point type tip. Fluid, preferably conductive fluid, is applied to the proximal end of the hollow electrode/tip, and expelled from the distal end thereof during electrocautery. The ball point distal tip allows the distal tip to be directly applied to the tissue and “rolled” or slid along the tissue. This allows the distal tip to be moved across the tissue without dragging or snagging on the tissue. In addition, the conductive fluid expelled from the distal tip further lubricates the distal tip as it moves across the tissue. If conductive fluid is used, the conductive fluid emanating from the electrode/tip conducts the RF electrocautery energy away from the distal tip so that it is primarily the fluid, rather than the distal tip that actually accomplishes the cauterizing of tissue.

Abstract: The present invention provides systems, apparatus and methods for selective applying energy to a patient's dermis tissue to generate the growth of new collagen in this tissue, while minimizing the effect on the outer epidermis layer, thereby minimizing or suppressing the wound healing phase of the procedure. In one aspect of the invention, a method includes positioning a first electrode adjacent to, or in contact with, a region on or within a patient's skin, and applying a sufficient high frequency voltage between the first electrode and a second electrode to create a heat injury to a target tissue within the patient's dermis layer without ablating the epidermis layer overlying the target tissue. Typically, the voltage applied to the first and second electrodes is sufficient to induce heating of the dermis layer to about 60°-80° C., preferably about 65°-75° C.

Abstract: A device for performing the maze procedure through the pericardial space, which includes a very flexible catheter for laying down lesions in conformity with the atrium of the heart.

Abstract: This invention is a circumferential ablation device assembly which is adapted to form a circumferential conduction block in a pulmonary vein. The assembly generally comprises a handheld surgical ablation probe having a rigid shaft for insertion through a patient's chest and a circumferential ablation element mounted on the distal end portion of the shaft. The circumferential ablation element is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes the pulmonary vein lumen. The circumferential ablation element includes an expandable member for anchoring the distal end portion of the shaft in a body structure and an ultrasound transducer disposed within the expandable member for emitting ultrasonic energy to ablate the tissue in the pulmonary vein.

Abstract: A computer generated image may be displayed inside an enclosure. The enclosure may include a transreflective surface so that the user can view the image generated by the computer system overlaid with a body part of the user. The computer generated images may move relative to the known position of the body part. As a result, the illusion is created that the physical body part interacts in a meaningful way with the computer generated image.

Abstract: An electrode catheter is introduced into a hollow anatomical structure, such as a vein, and is positioned at a treatment site within the structure. Tumescent fluid is injected into the tissue surrounding the treatment site to produce tumescence of the surrounding tissue which then compresses the vein. The solution may include an anesthetic, and may further include a vasoconstrictive drug that shrinks blood vessels. The tumescent swelling in the surrounding tissue causes the hollow anatomical structure to become compressed, thereby exsanguinating the treatment site. Energy is applied by an electrode catheter in apposition with the vein wall to create a heating effect. The heating effect causes the hollow anatomical structure to become molded and durably assume the compressed dimensions caused by the tumescent technique. The electrode catheter can be moved within the structure so as to apply energy to a large section of the hollow anatomic structure.

Abstract: Surgical apparatus includes bipolar electrodes and tissue-shearing blades configured to electrically contact tissue for electrocauterization thereof prior to shearing contact of the cutting blades with the tissue over wide angles of presentation of the tissue to the electrodes and blades. Extensions or protrusions disposed along facing edges of the electrodes separate the level at which tissue is electrically contacted by the electrodes from the level at which tissue is sheared by the cutting blades.

Abstract: Electrosurgical methods, systems, and apparatus for the controlled ablation of tissue from a target site of a patient. An electrosurgical instrument includes a working portion having a plurality of working zones differentiated according to their relative rates of aspiration and ablation. The instrument further includes an aspiration channel in communication with a plurality of aspiration ports, and a plurality of active electrodes disposed on the working portion. Each of the plurality of working zones may have at least one of the plurality of active electrodes and at least one of the plurality of aspiration ports. The aspiration rate of each working zone is dependent, inter alia, on the number, size, and distribution of the aspiration ports on that zone. In one embodiment, the ablation rate of a working zone is inversely related to the aspiration rate of that zone. Each of the plurality of active electrodes is adapted for ablating tissue to form low molecular weight ablation by-products.