Abstract: A system for monitoring ablation size is provided and includes a power source including a microprocessor for executing at least one control algorithm. A microwave antenna is configured to deliver microwave energy from the power source to tissue to form an ablation zone. A radiation detection device is operably disposed on the microwave antenna. The radiation detection device is configured to generate a voltage corresponding to a radius of the ablation zone, wherein the radiation detection device is in operative communication with at least one module associated with the power source. The at least one module triggers a signal when a predetermined threshold voltage is measured corresponding to the radius of the ablation zone.

Abstract: The invention relates to electrodes used in ablation catheter devices, where the electrodes contain two or more thermal sensors at different positions within the electrode that are capable of detecting temperature differences along the external surface of the electrode. In preferred embodiments, the thermal sensors are separated by one or more thermal insulating members and the thermal sensors are positioned near the external surface of the electrode at about the same distance from the end of the electrode, so that temperature measurements can indicate the position of the electrode with respect to the tissue desired to be ablated.

Abstract: A medical device for treating and analyzing tissue is disclosed. The device includes a plasma applicator having a housing. The housing includes a substantially tubular shape and defining a lumen therethrough. The lumen is in fluid communication with an ionizable media source configured to supply ionizable media thereto. The applicator also includes one or more electrodes coupled to the housing. The electrodes are adapted to couple to a power source configured to that energizes electrodes to ignite the ionizable media to form a plasma plume for treating tissue. The device also includes an effluent-collection attachment coupled to the plasma applicator, the effluent-collection attachment configured to collect at least a portion of a plasma effluent.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter that has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition. The carrier assembly includes multiple electrodes that are configured to ablate tissue at low power. Additional embodiments include a system that includes an interface unit for delivering one or more forms of energy to the ablation catheter.

Abstract: A method of controlling electrosurgical power delivery based on a comparison of sensed tissue impedance to various impedance threshold values is provided. Energy is delivered to tissue in a sealing cycle as a series of pulses. An initial pulse has a profile with a preset energy starting value that increases at a ramping rate to a preset end value. Sensed impedance data are monitored throughout each pulse and compared to each of an impedance threshold value for RF setpoint, an impedance threshold value for cumulative time, and an impedance threshold value for energy cutback. Based on sensed impedance during a pulse, the profile of a subsequent pulse can be modified. In the event of a high impedance event that reflects low tissue presence, energy may be cutback. A sealing cycle is stopped when a cumulative amount of time with an impedance value over the impedance cumulative time threshold value reaches a sealing cycle duration limit.

Abstract: An apparatus comprises a catheter, a conductive element and a balloon. The catheter has a lumen. The conductive element is disposed along the catheter. The balloon has an interior in fluid communication with the lumen of the catheter. The balloon is formed of a conductive material conductively coupled to the conductive element. The balloon has a collapsed configuration and an expanded configuration.

Abstract: Tissue is treated using a radiofrequency power supply connected to an applicator having a chamber filled with an electrically non-conductive gas surrounded by a thin dielectric wall. A radiofrequency voltage is applied at a level sufficient to ionize the gas into a plasma and to capacitively couple the ionized plasma with the tissue to deliver radiofrequency current to ablate or otherwise treat the tissue.

Abstract: A medical device comprising a cell including an ablation element and a carrier configured to receive at least a portion of said ablation element is disclosed. The medical device further comprises a tube enclosing the cell. At least a portion of the tube includes a membrane and the tube includes at least one hole proximate the ablation element for facilitating fluid flow. The medical device further comprises a fluid inlet for providing fluid to the interior of the tube. A method of using the medical device is also disclosed.

Abstract: A redundant temperature monitoring system and method for an electrosurgical system are provided. The temperature monitoring circuit includes at least one temperature sensor for sensing a temperature at a measuring point, a first temperature measurement circuit coupled to the at least one temperature sensor for generating a first temperature value, a second temperature measurement circuit coupled to the at least one temperature sensor for generating a second temperature value, and a control circuit for determining a difference between the first and second temperature values and for comparing the difference to a first predetermined threshold. If the difference is greater than the first predetermined threshold, the control circuit generates a warning signal. If the difference is greater than a second predetermined threshold, the control circuit generates an alarm signal and/or shuts down a power source of the electrosurgical system.

Abstract: An ablation catheter including an inner tube having a length, a distal end and a longitudinal axis, a plurality of needles extending from the distal end of the inner tube and biased away from the longitudinal axis, an outer sheath slideably moveable relative to the inner tube to surround at least a portion of the length of the inner tube and its extending needles, and a radio frequency energy source electrically connected to the plurality of needles.

Abstract: An electrosurgical surgical instrument can comprise a handle and an end effector, wherein the end effector can comprise first and second jaws which can be opened and closed to capture tissue therebetween. The second jaw can comprise a first electrode and a second electrode while the first jaw can comprise an opposing electrode positioned opposite the first electrode and the second electrode when the jaws are in their closed position. The first and second electrodes can be independently and/or sequentially operated in order to conduct current between the first and second electrodes and opposing electrode in order to draw the tissue positioned between the first and second jaws toward the center of the first and second jaws and weld the tissue. In various other embodiments, other firing sequences of the electrodes are contemplated. During and/or after such tissue welding processes, a cutting member can be advanced to cut the tissue.

Abstract: An electrosurgical system is provided. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. A power source operably couples to the electrosurgical generator and is configured to deliver power to one or more types of loads connected to the electrosurgical generator. The electrosurgical generator includes a controller including a microprocessor coupled to the electrosurgical generator and configured to control the output of the electrosurgical generator. A fiber optic connection circuit is in operative communication with the controller and includes one or more types of logic devices and one or more types of fiber optic channels. The fiber optic connection circuit is configured to mitigate leakage current associated with at least one of a plurality of components operatively associated with the electrosurgical generator by providing isolation.

Abstract: A surgical instrument can comprise a handle, a first conductor, a second conductor, and an end effector. The end effector can comprise a first jaw, a second jaw, wherein the first jaw is movable relative to the second jaw in order to capture tissue intermediate the first jaw and the second jaw, a first electrode electrically coupled with the first conductor, and a second electrode electrically coupled with the second conductor, wherein the second electrode is comprised of a material configured to have a first electrical resistance when a first pressure is applied to the material, and wherein the material is configured to have a second electrical resistance when a second pressure is applied to the material. In various circumstances, the material can be configured such that, once the applied pressure has exceeded a switching pressure, the resistance of the material can switch from the first resistance to the second resistance.

Abstract: Catheters, systems, and methods are provided for performing medical procedures, such as tissue ablation, adjacent the ostia of anatomical vessels, such as pulmonary veins. The catheter comprises an elongated flexible catheter body, which includes a proximal shaft portion and a distal shaft portion, and a tracking element carried by the distal shaft portion. The proximal section is pre-shaped to form a curve having an apex sized to be inserted into the vessel ostium, and a distal section configured to contact the adjacent tissue when the curve apex is inserted within the vessel ostium. The method may comprise inserting the curve apex into the vessel ostium to place the distal section in contact with a first tissue site adjacent the vessel ostium, and determining a location of the tracking element(s) within a coordinate system while the distal section is in contact with the first tissue site.

Abstract: A return pad for use with an electrosurgical system is disclosed. The return pad includes a conductive layer, a contact layer configured to engage a patient's skin and an intermediate layer disposed between the conductive layer and the contact layer. The intermediate layer is adapted to distribute energy.

Abstract: A radio frequency tissue ablation system with a radio frequency generator, the generator comprising a radio frequency source, at least four independently controllable radio frequency outputs, a user interface and a controller configured to delivery radio frequency energy from the radio frequency source to the radio frequency outputs in one of at least two different output configurations in response to a configuration selection made through the user.

Abstract: The invention relates to a flexible assembly for use in a region of a medical or surgical device. In preferred embodiments, the flexible region comprises a set of pull wires for controllably moving a treatment end of the device, and elements to separate the pull wires and maintain the integrity of the shaft of the flexible region in order to improve the operating aspects of the device. The devices and methods can be especially useful in ablation treatments, such as ablation at cardiac or epicardial tissues.

Abstract: An electrosurgical surgical instrument can comprise a handle and an end effector, wherein the end effector can comprise first and second jaws which can be opened and closed to capture tissue therebetween. One or both of the first and second jaws can comprise a plurality of electrodes which can be sequentially activated. The electrodes can be activated in a predetermined order in connection with a cutting member being advanced through the tissue. In various embodiments, the electrodes can be deactivated in a predetermined order. In certain embodiments, the electrodes can be comprised of a positive temperature coefficient material which can allow the electrodes to be sequentially deactivated.

Abstract: According to some embodiments, a method of treating a subject having diabetes or symptoms associated with diabetes is provided. The method includes delivering a neuromodulation catheter within a vessel (e.g., hepatic artery) having surrounding nerves that innervate the liver (e.g., sympathetic nerves of the hepatic plexus). The method may also include modulating (e.g., disrupting, ablating, stimulating) the nerves by mechanical compression, energy delivery, or fluid delivery.

Abstract: An electrosurgical surgical instrument can comprise a handle and an end effector, wherein the end effector can comprise first and second jaws which can be opened and closed in order to capture tissue therebetween. In various embodiments, the first and second jaws can comprise one or more electrodes configured to apply a voltage across the tissue thereby causing current to flow through the tissue and, as a result, generate heat within the tissue. The surgical instrument can further comprise a fluid circulatory system embedded within at least a portion the end effector wherein, in at least one embodiment, the fluid can be dispensed from the fluid circulatory system and onto the jaws of the end effector and/or the tissue positioned between the jaws.