Patent•
Multiple antenna ablation apparatus and method
03 Nov 1997-
TL;DR: In this paper, a volumetric ablation is achieved without impeding out any of the deployed antennas when 5 to 200 watts of electromagnetic energy is delivered from the electromagnetic energy source to the multiple antenna ablation device.
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 5 to 200 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.
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Patent•
19 Jun 1996TL;DR: In this article, the authors present a controller that can cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across output connections is limited to at least a first predetermined threshold value for cutting or vaporization of tissue, and a second output signal with a power supply coupled to the output stage for supplying power to output stage.
Abstract: In an electrosurgical generator for generating radio frequency power, the generator includes a radio frequency output stage having two or more output connections, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to at least a first predetermined threshold value for cutting or vaporisation of tissue, and a second output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to a second threshold value for coagulation. There is also provided adjustment means, operable by a user of the electrosurgical generator, for changing between various preset settings for the blended signal, the preset settings each having a predetermined duty cycle of the blended signal that is limited to the first threshold value for cutting or vaporisation, and a predetermined duty cycle of the blended signal that is limited to the second threshold value for coagulation.
1,486 citations
Patent•
02 May 1996TL;DR: An electrosurgical system including an electrode assembly having two electrodes for use immersed in an electrically conductive fluid has a generator with control circuitry for rapidly reducing the delivered radio frequency output power by at least 50% within at most a few cycles of the peak frequency output voltage reaching a predetermined threshold limit as discussed by the authors.
Abstract: An electrosurgical system including an electrode assembly having two electrodes for use immersed in an electrically conductive fluid has a generator with control circuitry for rapidly reducing the delivered radio frequency output power by at least 50% within at most a few cycles of the peak radio frequency output voltage reaching a predetermined threshold limit. In this way, tissue coagulation can be performed in, for example, saline without significant steam generation. The same peak voltage limitation technique is used in a tissue vaporization or cutting mode to limit the size of the steam pocket at the electrodes and to avoid electrode burning.
885 citations
Patent•
16 Mar 2000
TL;DR: In this paper, the authors present a system and methods for reducing the incidence of post-surgical tissue adhesions due to surgical incisions or perforations by applying heat, coolant, and/or sealant to or around the edges of the injured tissues, particularly to those in the peritoneum.
Abstract: The present invention provides systems and methods for reducing the incidence of post-surgical tissue adhesions due to surgical incisions or perforations by applying heat, coolant, and/or sealant to or around the edges of the injured tissues, particularly to those in the peritoneum. One aspect of the invention is RF energy delivery systems (200), and control methods thereof. The RF delivery system is typically arranged to be coupled to a conventional surgical tool such as a trocar (70), and may include a surgical sheet (400), with one or more electrodes (401) for delivering the RF energy to the injured tissue resulting from conventional incisions into the abdominal wall. The treatment dosage of RF heat to the injured tissue may be controlled by monitoring parameters such as treatment time, change in tissue temperature, change in tissue dimension, and change in tissue impedance.
836 citations
Patent•
05 Oct 2005
TL;DR: In this article, a pulsed electric field was used to induce electroporation or electrofusion of percutaneous intravascular vessels to reduce expansion of an acute myocardial infarction, reduce or prevent the onset of morphological changes that are affiliated with congestive heart failure, and/or be efficacious in the treatment of end stage renal disease.
Abstract: Methods and apparatus are provided for renal neuromodulation using a pulsed electric field to effectuate electroporation or electrofusion. It is expected that renal neuromodulation (e.g., denervation) may, among other things, reduce expansion of an acute myocardial infarction, reduce or prevent the onset of morphological changes that are affiliated with congestive heart failure, and/or be efficacious in the treatment of end stage renal disease. Embodiments of the present invention are configured for percutaneous intravascular delivery of pulsed electric fields to achieve such neuromodulation.
751 citations
Patent•
11 Jan 2002TL;DR: In this article, a system for palliatively treating a pain-causing tumor on or in bone is described, which includes an instrument (286) having a distal-end structure (294) adapted to be inserted into the bone tumor, where the structure is activatable to ablate tumor tissue, and a conduit in the instrument through which a liquid can be supplied to the tumor, when the ablating structure is inserted in the tumor.
Abstract: Disclosed is a system for palliatively treating a pain-causing tumor on or in bone. The system includes an instrument (286) having a distal-end structure (294) adapted to be inserted into the bone tumor, where the structure (294) is activatable to ablate tumor tissue, and a conduit in the instrument through which a liquid can be supplied to the tumor, when the ablating structure is inserted into the tumor. Also included are a first connecting structure for connecting the distal-end structure (294) to an activating device, such as an RF current source, and a second connecting structure for connecting the conduit to a source of the liquid.
732 citations
References
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Patent•
20 Jun 1996
TL;DR: In this article, an electrosurgical instrument for the treatment of tissue in the presence of an electrically-conductive fluid was disclosed, consisting of an instrument shaft (32), and a tissue treatment electrode (31) at one end of the shaft.
Abstract: An electrosurgical instrument is disclosed for the treatment of tissue in the presence of an electrically-conductive fluid. The instrument comprises an instrument shaft (32), and a tissue treatment electrode (31) at one end of the shaft, the tissue treatment electrode being constructed to define a plurality of pockets for trapping electrically-conductive fluid. Alternatively, the tissue treatment electrode (81) is made from an electrically-conductive material (81a) and is coated with a resistive inert material (81b) which is effective to increase the local power density within the tissue treatment electrode.
3,721 citations
Patent•
15 Oct 1991
TL;DR: In this paper, the authors describe a surgical instrument useful for laparoscopic surgery comprising an insulated shaft, a control means and a connection to an electrosurgical radiofrequency power source, its distal end having a tissue-engaging ledge, and the shaft supporting a tissueengaging clamping or cutting member movable toward the ledge in response to the control means so that an artery or other tissue in the pocket of the J-hook can be clamped or cut while radiofrequency current is applied.
Abstract: A surgical instrument useful for laparoscopic surgery comprising an insulated shaft, a control means and a connection to an electrosurgical radiofrequency power source, its distal end being of general J-hook form having a tissue-engaging ledge, and the shaft supporting a tissue-engaging clamping or cutting member movable toward the ledge in response to the control means so that an artery or other tissue in the pocket of the J-hook can be clamped or cut while radiofrequency current is applied. Instrument constructions disclosed incorporate one or two clamping members and a cutting member arranged such that with actuation, the clamping member(s) engages the ledge before the cutting member, and, by selective actuation of the electrosurgical power source, coagulation current can be applied while clamping an artery or other tissue against the ledge to stop flow of blood, and by further actuation of the control and suitable current to the cutting member, the artery or tissue may be cut. Selector means enable movement of one and prevent movement of one of the members during actuation; bipolar or monopolar energization is employed; the relatively long leg of the J-member has portals. Communicating through a lumen in the shaft for infusion or aspiration of fluid; the distal end surface of the J-hook defines a cutting edge for blunt dissection; and the control means comprises a single actuatable member by actuator rods for sealing clamp and cutting members, while a compression spring associated with the actuating rod of the sealing clamp member compresses when the clamp member is stopped, in clamping action upon the artery or tissue while cutting of tissue thereafter proceeds. A diamond film on tissue-engaging surfaces of a clamp, grasping or cutting surgical instrument improves heat transfer between tissue and instrument.
2,088 citations
Patent•
11 Aug 1993
TL;DR: A medical probe device comprises a catheter having a stylet guide housing with one or more stylet ports in a side wall of the probe, which can be used to direct a flexible stylet outward through the stylet port and through intervening tissue at a preselected, adjustable angle to a target tissue as discussed by the authors.
Abstract: A medical probe device comprises a catheter having a stylet guide housing with one or more stylet ports in a side wall thereof and a stylet guide for directing a flexible stylet outward through the stylet port and through intervening tissue at a preselected, adjustable angle to a target tissue. The total catheter assembly includes a stylet guide lumen communicating with the stylet port and a stylet positioned in said stylet guide lumen for longitudinal movement from the port through intervening tissue to a target tissue. The stylet can be an electrical conductor enclosed within a non-conductive layer, the electrical conductor being a radiofrequency electrode. Preferably, the non-conductive layer is a sleeve which is axially moveable on the electrical conductor to expose a selected portion of the electrical conductor surface in the target tissue. The stylet can also be a microwave antenna. The stylet can also be a hollow tube for delivering treatment fluid to the target tissue. It can also include a fiber optic cable for laser treatment. The catheter can include one or more inflatable balloons located adjacent to the stylet port for anchoring the catheter or dilation. Ultrasound transponders and temperature sensors can be attached to the probe end and/or stylet. The stylet guide can define a stylet path from an axial orientation in the catheter through a curved portion to a lateral orientation at the stylet port.
1,634 citations
Patent•
30 Sep 1988
TL;DR: In this paper, a vibratable tip for ultrasonically disintegrating tissue in a surgical procedure and for aspirating the disintegrated tissue and fluids away from the surgical site through an opening in the tip was presented.
Abstract: An apparatus having a vibratable tip for ultrasonically disintegrating tissue in a surgical procedure and for aspirating the disintegrated tissue and fluids away from the surgical site through an opening in the tip. A connection to an electrosurgical unit provides for delivery of RF cutting current, RF coagulating current or a blend thereof to the tip so that electrosurgical procedures can be conducted separately or simultaneously with ultrasonic aspiration through the tip. It thus is now possible, for example, to electrocauterize simultaneously with ultrasonic fragmentation with a single handheld surgical device. The simultaneous delivery of ultrasonic vibrations and RF current to the tip also has been found to increase the tissue fragmentation rate.
1,288 citations
Patent•
04 May 1992
TL;DR: In this paper, an electrical circuit system, which provides electrical energy to a surgical apparatus having ultrasonic fragmentation, aspiration, and electrosurgical coagulation capabilities, is presented, which includes an impedance sensing network and automatic feedback power output control to reduce RF power output as load impedance increases.
Abstract: An electrical circuit system (1) which provides electrical energy to a surgical apparatus having ultrasonic fragmentation, aspiration and electrosurgical coagulation capabilities, which system also includes an impedance sensing network (10) and automatic feedback power output control to reduce RF power output as load impedance increases, thereby reducing RF leakage current.
1,146 citations