Abstract: An ablation apparatus includes a multiple antenna device coupled to an electromagnetic energy source that produces an electromagnetic energy ablation output. The multiple antenna device includes a primary antenna with a lumen and a longitudinal axis, and a secondary antenna deployable from the lumen in a lateral direction relative to the longitudinal axis. At least a distal end of each secondary antenna is structurally less rigid than the primary antenna, and the primary antenna is sufficiently rigid to be introduced through tissue. At least one cable coupling the multiple antenna device to the energy source. A cooling element is coupled to the primary antenna. A variety of energy sources can be used including RF, microwave and laser.

Abstract: An RF treatment system includes first and second catheters with first and second needle electrodes positioned at least partially in lumens of the first and second catheters. Each electrode is surround by a insulator sleeve which is slideable along the electrode and defines an ablation surface. An RF power source is coupled to the first and second needle electrodes. The electrodes provide bipolar RF ablation between the two, defining an ablation volume. A deflectable introducer has a laterally deflectable distal end and an ablation volume temperature sensor positioned at the distal end. The deflectable introducer is advanced in and out of the electrodes distal ends to measure a temperature of tissue in the ablation volume. The treatment system can include more than two electrodes, such as two pairs of electrodes. Further, the system can include a needle electrode extension with a laterally deflectable distal end.

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: 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 device 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, and has a second radius of curvature, or a substantially linear geometry.

Abstract: An RF treatment apparatus provides multi-modality treatment for tumors and other desired tissue masses, and includes an RF indifferent electrode and an RF active electrode. The RF indifferent electrode has a compacted, non-deployed state, and an expanded deployed state. In the deployed state, the RF indifferent electrode forms a helical structure with four or less coils that surround an exterior of the tumor. The indifferent electrode becomes a microwave antenna when it is coupled to a microwave source. RF ablation energy is delivered to the tumor by the RF active electrode after it has been introduced into the tumor. Both electrodes are coupled to an RF energy source. The indifferent electrode is coupled to a microwave source. Either or both of the electrodes is hollow and include fluid distribution ports for the purpose of providing a chemotherapeutic agent to the tumor site. Ablation energy is supplied to the tumor by the active electrode.

Abstract: A medical ablation device comprising a flexible RF electrode wire or tube, the terminal portion thereof extending through an insulating sleeve axially moveable thereon. The electrode and surrounding sleeve extend through a portion of a rigid tube having a distal end adapted to be inserted into the body of a patient. Tabs are attached to the proximal end of the sleeve and electrode for advancing them together from the terminal end of the tube, for retracting the sleeve from the distal end of the electrode to expose a predetermined area of electrode surface, and for retracting them together into the terminal end of the tube. The electrode can also be a hollow tube, the proximal end thereof being adapted to be connected to a suction source for aspiration of tissue adjacent its distal end or it can optionally contain a fiber optic, the end thereof being enclosed within the tube and closely adjacent its distal end.

Abstract: A method of this invention for treating body tissues containing cancerous cells or non-malignant tumors with RF ablation, alone or in combination with systemic or localized chemotherapy comprising introducing a stylet comprising an electrode surface and a sleeve longitudinally moveable thereon into the vicinity of the body tissues, retracting the sleeve from a portion of the electrode surface, and supplying RF power to the electrode surface sufficient to heat the tissue to a temperature of above about 45.degree. C. for a time to cause reduction of tissue mass in the vicinity of the electrode. The RF power supplied to the electrode surface is sufficient to effect a desiccated fluid diffusion barrier capsule surrounding the body tissue being treated. The stylet can include a hollow tube having fluid distribution ports therein, and the method can include the step of passing fluid through one or more distribution ports into the body tissue being treated.

Abstract: A method of this invention for treating body tissues containing cancerous cells or non-malignant tumors with RF ablation, alone or in combination with systemic or localized chemotherapy comprising introducing a stylet comprising an electrode surface and a sleeve longitudinally moveable thereon into the vicinity of the body tissues, retracting the sleeve from a portion of the electrode surface, and supplying RF power to the electrode surface sufficient to heat the tissue to a temperature of above about 45.degree. C. for a time to cause reduction of tissue mass in the vicinity of the electrode. The RF power supplied to the electrode surface is sufficient to effect a desiccated fluid diffusion barrier capsule surrounding the body tissue being treated. The stylet can include a hollow tube having fluid distribution ports therein, and the method can include the step of passing fluid through one or more distribution ports into the body tissue being treated.