Abstract: An ablation apparatus includes a handpiece, an electrode extending from a handpiece distal end, a probe, a thermal sensor and an energy source. The electrode includes a distal end and a lumen, a cooling medium inlet conduit and a cooling medium exit conduit. Both conduits extend through the electrode lumen to an electrode distal end. A sidewall port, isolated from a cooling medium flowing in the inlet and outlet conduits, is formed in the electrode. The probe is at least partially positionable in the electrode lumen and configured to be advanced and retracted in and out of the sidewall aperture. The thermal sensor is supported by the probe. The electrode is coupled to an energy source.

Abstract: A tissue ablation apparatus includes a delivery catheter with distal and proximal ends. A handle is attached to the proximal end of the delivery catheter. At least partially positioned in the delivery catheter is an electrode deployment device. The electrode deployment devices includes a plurality of retractable electrodes. Each electrode has a non-deployed state when it is positioned in the delivery catheter. Additionally, each electrode has a distended deployed state when it is advanced out of the delivery catheter distal end. The deployed electrodes define an ablation volume. Each deployed electrode has a first section with a first radius of curvature. The first section is located near the distal end of the delivery catheter. A second section of the deployed electrode extends beyond the first section, ad has a second radius of curvature, or a substantially linear geometry.

Abstract: A cell necrosis apparatus includes an introducer with a distal end sufficiently sharp to penetrate tissue. An energy delivery device has a first set of RF electrodes and a second set of RF electrodes. Each RF electrode of the first and second sets has a tissue piercing distal end and is positionable in the introducer as the introducer is advanced through tissue. The first and second sets of RF electrodes are deployable with curvature from the introducer. The second set of RF electrodes is deployable a greater distance from the introducer than the first set of RF electrodes.

Abstract: A cell necrosis apparatus includes an introducer with a distal end sufficiently sharp to penetrate tissue. An energy delivery device has a first set of RF electrodes, a second set of RF electrodes and a third RF electrode. Each of electrodes has a tissue piercing distal end and is positionable in the introducer as the introducer is advanced through tissue. The first and second sets of RF electrodes are deployable with curvature from the introducer. The third RF electrode is deployable from the introducer with less curvature than the first and second sets of RF electrodes. The second set of RF electrodes is deployable a greater distance from the introducer than the first set of RF electrodes.

Abstract: An ablation apparatus includes an introducer with a distal end sufficiently sharp to penetrate tissue. An energy delivery device is configured to be coupled to an energy source. The energy delivery device includes a first electrode and a second electrode each with a tissue piercing distal portion. The first and second electrodes are at least partially positionable in the introducer and deployable from the introducer at a selected tissue site to an expanded state. In the expanded state the deployed first and second electrodes distend laterally away from the introducer with a radius of curvature to form a shaped array of deployed electrodes at the tissue site when positioned at the selected tissue site. The first electrode distal portion and the second electrode distal portion are each at least partially made of a shaped memory alloy material that displays stress induced martensite behavior above body temperature. A cable couples the energy source to the energy delivery device.

Abstract: A cell necrosis apparatus has a flexible introducer including a lumen and a distal end sufficiently sharp to penetrate tissue. An energy delivery device is positionable in the introducer as the introducer is advanced through tissue. The energy delivery device includes a first RF electrode with a tissue piercing distal portion and a second RF electrode with a tissue piercing distal portion. The first and second RF electrodes are deployable with curvature from the introducer at a selected tissue site in a lateral direction away from the periphery of the introducer.

Abstract: A tissue ablation apparatus includes a delivery catheter with distal and proximal ends. A handle is attached to the proximal end of the delivery catheter. At least partially positioned in the delivery catheter is an electrode deployment device. The electrode deployment devices includes a plurality of retractable electrodes. Each electrode has a non-deployed state when it is positioned in the delivery catheter. Additionally, each electrode has a distended deployed state when it is advanced out of the delivery catheter distal end. The deployed electrodes define an ablation volume. Each deployed electrode has a first section with a first radius of curvature. The first section is located near the distal end of the delivery catheter. A second section of the deployed electrode extends beyond the first section, ad has a second radius of curvature, or a substantially linear geometry.

Abstract: An ablation apparatus includes a handpiece, an electrode extending from a handpiece distal end, a probe, a thermal sensor and an energy source. The electrode includes a distal end and a lumen, a cooling medium inlet conduit and a cooling medium exit conduit. Both conduits extend through the electrode lumen to an electrode distal end. A sidewall port, isolated from a cooling medium flowing in the inlet and outlet conduits, is formed in the electrode. The probe is at least partially positionable in the electrode lumen and configured to be advanced and retracted in and out of the sidewall aperture. The thermal sensor is supported by the probe. The electrode is coupled to an energy source.

Abstract: An ablation apparatus has an introducer including an introducer lumen, a proximal portion and a distal portion. Two or more electrodes are at least partially positionable in the introducer lumen. Each electrode is configured to be advanced from the introducer distal portion in a deployed state into a selected tissue site to define a volumetric ablation volume. A fluid delivery member is positioned on at least a portion of an exterior of one of the electrodes. The fluid delivery member is configured to be coupled to a fluid medium source. A cable is coupled to the electrodes.

Abstract: A cell necrosis apparatus has a flexible introducer including a lumen and a distal end sufficiently sharp to penetrate tissue. An energy delivery device is positionable in the introducer as the introducer is advanced through tissue. The energy delivery device includes a first RF electrode with a tissue piercing distal portion and a second RF electrode with a tissue piercing distal portion. The first and second RF electrodes are deployable with curvature from the introducer at a selected tissue site in a lateral direction away from the periphery of the introducer.

Abstract: An ablation treatment apparatus includes an energy source. A multiple antenna device is included and has a primary antenna with a longitudinal axis, a central lumen and a distal end, and a secondary antenna with a distal end. The secondary antenna is positionable in the primary antenna after the primary antenna is positioned at a tissue site and deployed from the primary antenna central lumen in a lateral direction relative to the longitudinal axis. A selected primary or secondary antenna is electromagnetically coupled to the energy source. A non-selected antenna is electromagnetically coupled to the selected antenna. A cable connects the energy source to the selected antenna.

Abstract: An RF treatment apparatus includes a catheter with a catheter lumen. A removable needle electrode is positioned in the catheter lumen in a fixed relationship to the catheter. The needle electrode includes a needle lumen and a needle electrode distal end. A removable introducer is slidably positioned in the needle lumen. The introducer includes an introducer distal end. A first sensor is positioned on a surface of the needle electrode or the insulator. An RF power source is coupled to the needle electrode and a return electrode. An insulator sleeve is slidably positioned around the electrode and includes a second sensor. Resources are associated with the electrodes, sensors as well as the RF power source for maintaining a selected power at the electrode independent of changes in current or voltage.

Abstract: An ablation apparatus has a multiple antenna device with a primary antenna and a secondary antenna positionable in a lumen of the primary antenna. The secondary antenna is at least partially deployable from the primary antenna in a lateral direction relative to a longitudinal axis of the primary antenna with at least one radius of curvature. A distal end of the primary antenna is sufficiently sharp to pierce tissue. The primary and secondary antennas are configured to provide a selectable geometric ablation of a selected tissue mass. An insulation sleeve is positioned on an exterior of the primary antenna. One or more cables are coupled to the multiple antenna device.

Abstract: An ablation treatment apparatus has a multiple antenna device. The multiple antenna device includes a primary antenna with a lumen, a longitudinal axis and an ablative surface area of length L.sub.1. The multiple antenna device also includes a secondary antenna that is positionable in the primary antenna. A secondary antenna distal end is deployed at a selected tissue site from the primary antenna lumen in a lateral direction relative to the longitudinal axis. A sensor is at least partially positioned at an exterior of the secondary antenna distal end at a distance L.sub.2 from the primary antenna along the secondary antenna distal end. L.sub.2 is at least equal to 1/3 L.sub.1. An energy source is coupled to the primary antenna.

Abstract: An ablation treatment apparatus has a multiple antenna device. The multiple antenna device includes a primary antenna with a lumen and a longitudinal axis, and a secondary antenna positionable in the lumen. At a selected tissue site the secondary antenna is deployed in a lateral direction relative to the longitudinal axis of the primary antenna. At least a portion of a distal end of the secondary antenna is structurally less rigid than the primary antenna. The primary antenna is constructed to be rigid enough to be introduced through tissue. A cable couples one or both of the antennas to an energy source.

Abstract: An ablation apparatus has an introducer including an introducer lumen, a proximal portion and a distal portion. A handpiece with a proximal portion and a distal portion is coupled to the introducer proximal portion. Two or more electrodes are at least partially positioned in the introducer lumen. Each electrode is configured to be advanced from the introducer distal portion in a deployed state into a selected tissue site to define a volumetric ablation volume. A fluid delivery member is positioned on at least a portion of an exterior of one of the electrodes. The fluid delivery member is configured to be coupled to a fluid medium source. A cable is coupled to the electrodes.

Abstract: An ablation apparatus includes an energy source producing an ablation energy output. A multiple antenna device is included and has a primary antenna with a longitudinal axis, a central lumen and a distal end, and a first secondary antenna with a distal end. The first secondary antenna is deployed from the primary antenna central lumen in a lateral direction to the longitudinal axis. The primary antenna is coupled to the energy source to receive the ablation energy output, and the first secondary antenna is coupled to the primary antenna to receive ablation energy from the primary antenna. A sensor is positioned at one or both of the primary or secondary antennas. A feedback control system is coupled to the energy source and the sensor. The feedback control system is responsive to a detected characteristic from the sensor to provide a delivery of ablation energy output from the energy source to the antennas.

Abstract: A multiple antenna ablation apparatus includes an electromagnetic energy source, a trocar including a distal end, and a hollow lumen extending along a longitudinal axis of the trocar, and a multiple antenna ablation device with three or more antennas. The antennas are initially positioned in the trocar lumen as the trocar is introduced through tissue. At a selected tissue site the antennas are deployable from the trocar lumen in a lateral direction relative to the longitudinal axis. Each of the deployed antennas has an electromagnetic energy delivery surface of sufficient size to, (i) create a volumetric ablation between the deployed antennas, and (ii) the volumetric ablation is achieved without impeding out any of the deployed antennas when 10 to 50 watts of electromagnetic energy is delivered from the electromagnetic energy source to the multiple antenna ablation device. At least one cable couples the multiple antenna ablation device to the electromagnetic energy source.

Abstract: An ablation treatment apparatus has a multiple antenna device. The multiple antenna device includes a primary antenna with a lumen, a longitudinal axis and an ablative surface area of length L.sub.1. The multiple antenna device also includes a secondary antenna that is positioned in the primary antenna as the primary antenna is introduced through tissue. A secondary antenna distal end is deployed at a selected tissue site from the primary antenna lumen in a lateral direction relative to the longitudinal axis. A sensor is at least partially positioned at an exterior of the secondary antenna distal end at a distance L.sub.2 from the primary antenna along the secondary antenna distal end. L.sub.2 is at least equal to 1/3 L.sub.1. An energy source is coupled to the primary antenna.

Abstract: An ablation treatment apparatus has a multiple antenna device with a primary antenna and a secondary antenna. The secondary antenna is positioned in a lumen of the primary antenna as the primary antenna is introduced through tissue to a selected tissue site. At the tissue site the secondary antenna is deployed from the primary antenna in a lateral direction relative to a longitudinal axis of the primary antenna. At least a portion of a distal end of the secondary antenna is structurally less rigid than the primary antenna. The primary antenna is constructed to be rigid enough to be introduced and advanced through tissue. A cable couples the energy source to one or more of the antennas.