1155 results about "Conductive fluid" patented technology

An electrosurgical system comprises a radio frequency generator (1), an electrosurgical instrument (E1), and a fluid enclosure (42). The generator (1) has a radio frequency output for delivery of power to the electrosurgical instrument (E1) when immersed in an electrically-conductive fluid. The electrosurgical instrument (E1) has an electrode assembly (32) at the distal end thereof, the electrode assembly comprising a tissue treatment electrode (34), and a return electrode (38) axially spaced therefrom in such a manner as to define, in use, a conductive fluid path that completes an electrical circuit between the tissue treatment electrode and the return electrode. The fluid enclosure (42) is adapted to surround an operation site on the skin of a patient or an incision leading to a cavity surgically created within the patient's body. The fluid enclosure (42) includes sealing means (44) for sealing against the patient's tissue, and the fluid enclosure includes at least one port (50a, 52a) through which the electrosurgical (E1) is insertable, and through which the electrically-conductive fluid can enter and / or leave the enclosure. The fluid enclosure device of the present invention can also be used to treat tumours within the colon. The enclosure, which includes a proximal and a distal bung, is inserted into the colon in a deflated condition and then inflated with a conductive fluid or gas. The colon can be supported against the pressure of the fluid or gas with a pressure sleeve that has been inserted to surround the region of the colon being treated. An electrosurgical instrument is then inserted into the colon and manipulated to vaporize the tumor.

The present invention provides an apparatus and a method for producing a virtual electrode within or upon a tissue to be treated with radio frequency alternating electric current, such tissues including but not limited to liver, lung, cardiac, prostate, breast, and vascular tissues and neoplasms. An apparatus in accord with the present invention includes a supply of a conductive or electrolytic fluid to be provided to the patient, an alternating current generator, and a processor for creating, maintaining, and controlling the ablation process by the interstitial or surficial delivery of the fluid to a tissue and the delivery of electric power to the tissue via the virtual electrode. A method in accord with the present invention includes delivering a conductive fluid to a predetermined tissue ablation site for a predetermined time period, applying a predetermined power level of radio frequency current to the tissue, monitoring at least one of several parameters, and adjusting either the applied power and / or the fluid flow in response to the measured parameters.

A sensing and ablation electrode includes bifurcated sensing limbs separated by an ablation web. The electrode is disposed on the distal end of a catheter. The sensing limbs each support an array of sensors that are individually wired for mapping and post ablation efficacy testing. The web includes a pair of pliable membranes that define a lumen and are adapted to collapse the cross-section of the electrode. One membrane defines a plurality of apertures for dispersing a conductive fluid medium as a virtual electrode. The sensors and the apertures all lie within substantially the same plane.

A method and apparatus for creating a virtual electrode to ablate bodily tissue. The apparatus includes an outer tube, a first electrode, an inner tube and a second electrode. The outer tube is fluidly connected to a source of conductive fluid and defines a proximal end and a distal end. The distal end includes an opening for delivering conductive fluid from the outer tube. The first electrode is disposed at the distal end of the outer tube for applying a current to conductive fluid delivered from the outer tube. The inner tube is coaxially received within the outer tube and is connected to a source of conductive fluid. The inner tube defines a proximal end and a distal end, with the distal end forming an opening for delivering conductive fluid from the inner tube. Finally, the second electrode is disposed at the distal end of the inner tube for applying a current to conductive fluid delivered from the inner tube. With this configuration, upon final assembly, the distal end of the outer tube is axially spaced from the distal end of the inner tube such that the first electrode is spaced from the second electrode. As a result, a bi-polar virtual electrode can be established.

Methods and apparatus for ablating a target tissue are discussed. Such methods and apparatus include those that simplify tissue ablation. For example, a tissue ablation device having an actuator, such as a trigger mechanism, coupled to a power source and an electrode is discussed. A single step of engaging the actuator causes the electrode to be introduced into the target tissue and causes energy to be delivered from the power supply to the tissue via the electrode. By way of additional example, a tissue ablation device having an actuator coupled to a fluid source and an electrode is discussed. A single step of engaging the actuator causes conductive fluid to flow from the fluid source to the target tissue location and causes the electrode to be introduced to the target tissue location. The fluid source may be a conductive fluid, such as saline, which may increase the efficiency of ablation. Various other configurations and methods that simplify tissue ablation are also discussed.

A wearable therapeutic device that includes a garment configured to contain an external defibrillator. The garment is configured to house at least one of an alarm module and a monitor and to house a first therapy electrode and a second therapy electrode. The garment is also configured to releasably receive a receptacle that contains a conductive fluid proximate to at least one of the first therapy electrode and the second therapy electrode, and to electrically couple the receptacle with the garment.

A flexible diagnostic device has a measurement cell that is sandwiched between the conductive surfaces of two conductive-coated insulating layers. At least one of the conductive surfaces is scored with an insulating pattern, so that the flow of a conductive fluid sample into the cell can be monitored.

Methods and apparatus for selectively applying electrical energy to a target location within a patient's body, particularly including tissue in the spine. In a method of the invention high frequency (RF) electrical energy is applied to one or more active electrodes on an electrosurgical probe in the presence of an electrically conductive fluid to remove, contract or otherwise modify the structure of tissue targeted for treatment. In one aspect, a dura mater and spinal cord are insulated from the electrical energy by an insulator positioned on a non-active side of the probe. In another aspect, a plasma is aggressively formed in the electrically conductive fluid by delivering a conductive fluid to a distal end portion of the probe and aspirating the fluid from a location proximal of the return electrode. In another aspect, a distal end of an electrosurgical probe having at least one electrode on a biased, curved, bent, or steerable shaft is guided or steered to a target site within an intervertebral disc having a disc defect for treatment of tissue to be treated at the target site by the selective application of electrical energy thereto.

Systems and methods are provided for applying a high frequency voltage in the presence of an electrically conductive fluid to create a relatively low-temperature plasma for ablation of tissue adjacent to, or in contact with, the plasma. In one embodiment, an electrosurgical probe or catheter is positioned adjacent the target site so that one or more active electrode(s) are brought into contact with, or close proximity to, a target tissue in the presence of electrically conductive fluid. High frequency voltage is then applied between the active electrode(s) and one or more return electrode(s) to non-thermally generate a plasma adjacent to the active electrode(s), and to volumetrically remove or ablate at least a portion of the target tissue. The high frequency voltage generates electric fields around the active electrode(s) with sufficient energy to ionize the conductive fluid adjacent to the active electrode(s). Within the ionized gas or plasma, free electrons are accelerated, and electron-atoms collisions liberate more electrons, and the process cascades until the plasma contains sufficient energy to break apart the tissue molecules, causing molecular dissociation and ablation of the target tissue.

A flapper is provided in the main conductive fluid supply inlet line, and a permanent magnet is affixed to the bottom of the flapper. Adjacent to the flapper, outside the pipe, a magnetically operated switch is placed. Conductive fluid sensors are placed in or on conductive fluid dependent appliances, to determine the presence or absence of flowing conductive fluids. The flapper's switch and the conductive fluid sensors are connected in circuit with a relay, which in turn controls an electrically actuated valve cutting off or permitting the entry of fluids from the source to the inlet pipe. If the switch is activated, and one or more of the fluid sensors is not, within a predetermined time period, then the electrically actuated valve will cut off the entry of fluids from the source to the inlet pipe. If the switch and sensors are activated concurrently, normal fluid flow will be permitted.

Methods and apparatus for selectively applying electrical energy to a target location within a patient's body, particularly including tissue in the spine. In a method of the invention high frequency (RF) electrical energy is applied to one or more active electrodes on an electrosurgical probe in the presence of an electrically conductive fluid to remove, contract or otherwise modify the structure of tissue targeted for treatment. In one aspect, a dura mater and spinal cord are insulated from the electrical energy by an insulator positioned on a non-active side of the probe. In another aspect, a plasma is aggressively formed in the electrically conductive fluid by delivering a conductive fluid to a distal end portion of the probe and aspirating the fluid from a location proximal of the return electrode. In another aspect, a distal end of an electrosurgical probe having at least one electrode on a biased, curved, bent, or steerable shaft is guided or steered to a target site within an intervertebral disc having a disc defect for treatment of tissue to be treated at the target site by the selective application of electrical energy thereto.

Disclosed is a robust tactile sensor array that mimics the human fingertip and its touch receptors. The mechanical components are similar to a fingertip, with a rigid core surrounded by a weakly conductive fluid contained within an elastomeric skin. It uses the deformable properties of the finger pad as part of the transduction process. Multiple electrodes are mounted on the surface of the rigid core and connected to impedance measuring circuitry within the core. External forces deform the fluid path around the electrodes, resulting in a distributed pattern of impedance changes containing information about those forces and the objects that applied them. Strategies for extracting features related to the mechanical inputs and using this information for reflexive grip control.