372 results about "Ablation radiofrequency" patented technology

This invention relates to the destruction of pathological volumes or target structures such as cancerous tumors or aberrant functional target tissue volumes by direct thermal destruction. In the case of a tumor, the destruction is implemented in one embodiment of the invention by percutaneous insertion of one or more radiofrequency probes into the tumor and raising the temperature of the tumor volume by connection of these probes to a radiofrequency generator outside of the body so that the isotherm of tissue destruction enshrouds the tumor. The ablation isotherm may be predetermined and graded by proper choice of electrode geometry and radiofrequency (rf) power applied to the electrode with or without temperature monitoring of the ablation process. Preplanning of the rf electrode insertion can be done by imaging of the tumor by various imaging modalities and selecting the appropriate electrode tip size and temperature to satisfactorily destroy the tumor volume. Computation of the correct three-dimensional position of the electrode may be done as part of the method, and the planning and control of the process may be done using graphic displays of the imaging data and the rf ablation parameters. Specific electrode geometries with adjustable tip lengths are included in the invention to optimize the electrodes to the predetermined image tumor size.

A system for efficient delivery of radio frequency (RF) energy to cardiac tissue with an ablation catheter used in catheter ablation, with new concepts regarding the interaction between RF energy and biological tissue. In addition, new insights into methods for coagulum reduction during RF ablation will be presented, and a quantitative model for ascertaining the propensity for coagulum formation during RF ablation will be introduced. Effective practical techniques a represented for multichannel simultaneous RF energy delivery with real-time calculation of the Coagulum Index, which estimates the probability of coagulum formation. This information is used in a feedback and control algorithm which effectively reduces the probability of coagulum formation during ablation. For each ablation channel, electrical coupling delivers an RF electrical current through an ablation electrode of the ablation catheter and a temperature sensor is positioned relative to the ablation electrode for measuring the temperature of cardiac tissue in contact with the ablation electrode. A current sensor is provided within each channel circuitry for measuring the current delivered through said electrical coupling and an information processor and RF output controller coupled to said temperature sensor and said current sensor for estimating the likelihood of coagulum formation. When this functionality is propagated simultaneously through multiple ablation channels, the resulting linear or curvilinear lesion is deeper with less gaps. Hence, the clinical result is improved due to improved lesion integrity.

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement through the atrial septum into the left atrium. The distal end of the sheath is expanded using a radial dilator. In one application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as electrophysiological mapping of the heart, radio-frequency ablation of left atrial tissue, placement of atrial implants, valve repair, or the like.

A system that interfaces with a workstation endocardial mapping system allows for the rapid and successful ablation of cardiac tissue. The system allows a physician to see a representation of the physical location of a catheter in a representation of an anatomic model of the patient's heart. The workstation is the primary interface with the physician. A servo catheter having pull wires and pull rings for guidance and a servo catheter control system are interfaced with the workstation. Servo catheter control software may run on the workstation. The servo catheter is coupled to an RF generator. The physician locates a site for ablation therapy and confirms the location of the catheter. Once the catheter is located at the desired ablation site, the physician activates the RF generator to deliver the therapy.

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the performance of procedures in the left atrium. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the right atrium and through the atrial septum into the left atrium. The distal end of the sheath is subsequently expanded using a radial dilatation device. In an exemplary application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as electrophysiological mapping of the heart, radio-frequency ablation of left atrial tissue, placement of left atrial implants, mitral valve repair, or the like.

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the performance of procedures in the left atrium. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the right atrium and through the atrial septum into the left atrium. The distal end of the sheath is subsequently expanded using a radial dilatation device. In an exemplary application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as electrophysiological mapping of the heart, radio-frequency ablation of left atrial tissue, placement of left atrial implants, mitral valve repair, or the like.

A thermal ablation system is operable to perform thermal ablation using an x-ray system to measure temperature changes throughout a volume of interest in a patient. Image data sets captured by the x-ray system during a thermal ablation procedure provide temperature change information for the volume being subjected to the thermal ablation. Intermediate image data sets captured during the thermal ablation procedure may be fed into a system controller, which may modify or update a thermal ablation plan to achieve volume coagulation necrosis targets. The thermal ablation may be delivered by a variety of ablation modes including radiofrequency ablation, microwave therapy, high intensity focused ultrasound, laser ablation, and other interstitial heat delivery methods. Methods of performing thermal ablation using x-ray system temperature measurements as a feedback source are also provided.

A method and device for determining the transmuriality and/or continuity of an isolation line formed by a plurality of point contact ablations. In one embodiment, a method for determining the size of a lesion (width, depth and/or volume) is disclosed, based on contact force of the ablation head with the target tissue, and an energization parameter that quantifies the energy delivered to the target tissue during the duration time of the lesion formation. In another embodiment, the sequential nature (sequence in time and space) of the ablation line formation is tracked and quantified in a quantity herein referred to as the “jump index,” and used in conjunction with the lesion size information to determine the probability of a gap later forming in the isolation line.

Methods and apparatus for delivering precise amounts of fluid under pressure into cardiac tissue for the purpose of facilitating ablation of the tissue along a desired lesion line. One method injects fluid under pressure through a discharge orifice in a needle-less injection device. The injected fluid can be a cytotoxic fluid and/or a highly conductive fluid injected in conjunction with radio frequency ablation to create an ablative virtual electrode. The injected fluid can provide deeper and narrower conduction paths and resulting lesions. Radio frequency ablation can be performed at the same time as the fluid injection, using the injection device as an electrode, or subsequent to the fluid injection, using a separate device. In some methods, the injected fluid is a protective fluid, injected to protect tissue adjacent to the desired lesion line. Fluid delivery can be endocardial, epicardial, and epicardial on a beating heart. The present methods find one use in performing maze procedures to treat atrial fibrillation.

An RF ablation system has a hollow conductive coaxial cable comprising inner and outer coaxial tubular conductors, and an ablating member mounted at the distal end portion of the cable for delivery of radio frequency energy including microwaves to the target body tissue. The inner conductor has a central lumen and extends at least up to the ablating member. At least one electromagnetic tracking sensor coil with a magnetic core is located in the central lumen at the distal end portion of the cable, close to the distal tip of the cable, and connected to a signal processing unit. An electromagnetic field generator positioned in the vicinity of a patient undergoing treatment generates an electromagnetic field which induces a voltage in the sensor coil. The signal processing unit uses the induced voltage to calculate the position and orientation of the distal end portion or tip of the catheter in a patient's body.

A method and device for determining the transmurality and/or continuity of an isolation line formed by a plurality of point contact ablations. In one embodiment, a method for determining the size of a lesion (width, depth and/or volume) is disclosed, based on contact force of the ablation head with the target tissue, and an energization parameter that quantifies the energy delivered to the target tissue during the duration time of the lesion formation. In another embodiment, the sequential nature (sequence in time and space) of the ablation line formation is tracked and quantified in a quantity herein referred to as the “jump index,” and used in conjunction with the lesion size information to determine the probability of a gap later forming in the isolation line.

The invention discloses a concentric, detachable and freely replaceable multifunctional targeted tumor scalpel used for treating various tumor treatments, which comprises an inner ring pipe and an inner pipe that are concentric. The mutual locations of the inner pipe and the outer ring pipe can be axially adjusted, and the inner pipe can be fixed on a handle through a connecting bar and can be detached from the outer ring pipe. The invention includes multifunctional applications of cold therapy, radio frequency ablation therapy, microwave ablation therapy, endothermknife therapy, laser ablation therapy, chemical therapy, radiation therapy, immunization therapy, gene therapy, photodynamic therapy, electrochemotherapy and the like. Meanwhile, the inner pipe of the multifunctional targeted tumor scalpel can also be used as a diagnosis monitoring device, such as a temperature sensor, a biopsy needle, a micro ultrasonic probe, an endoscope and the like. The multifunctional targeted tumor scalpel can realize the combination of single and/or multiple therapy methods.

The invention provides a radio frequency ablation (RFA) catheter system for denervation of sympathetic nerves in renal arteries. The system comprises an ablation catheter, a control handle, a guiding catheter and an ablation generating device and can be provided or not provided with an independent guiding catheter control handle, wherein the ablation catheter is formed by a catheter body section and an ablation section from near end to far end in sequence. The system is characterized in that the front end of the catheter body section also comprises a controllable bending section; the controllable bending section is connected with the control handle by the catheter body section; at least two independent structures are installed on the ablation section; and an ablation head is installed on at least one independent structure. The system can carry out multipoint ablation simultaneously, monitors the ablation effect during operation in real time, and has better mechanical stability.

A method of ablating a tissue site includes at least two stages. A first stage involves conducting bipolar ablation between a first pair of electrodes situated in an opposing arrangement on opposing sides of the tissue site to form a pair of opposing first stage ablation regions extending from respective sides of the tissue towards the center. A second stage involves conducting bipolar ablation between a second pair of electrodes situated in a diametrical arrangement with respect to the first stage ablation regions, which forms a second stage ablation region intermediate the pair of first stage ablation regions. The second stage completes the ablation through the entire depth of the tissue site. Since the overall process can accommodate incomplete ablation during the first stage, lower power, reduced ablation times or both may be used during the first stage, avoiding overheating and with a decrease in ablated tissue volume.

Radiofrequency ablation (RFA) may be used as a minimally invasive treatment of solid tumors, typically cancers of the liver, lung, breast, kidney and bone, most often via a percutaneous approach. In RFA tumor tissue is killed by heating. RFA requires guidance using an imaging method to correctly position the RF applicator. Magnetic resonance imaging (MRI) can be used for guidance, and offers the additional advantage of the ability to image tissue temperature. Because MRI employs high power RF fields, the MRI scanner could serve as the source of RF energy for ablation. Described herein are an MRI-driven RF ablation device and method. The device has minimal electrical circuitry, and uses the MR scanner radio frequency field as the energy source to generate heat in tissue using an antenna and a needle. Based on the Faraday induction law, different embodiments for coupling the body coil RF energy into tissue are disclosed.