2719 results about "Corneal ablation" patented technology

An ablation device for creating a lesion within a body is provided. The ablation device includes a shaft having a proximal end and a distal end, wherein at least a portion of the shaft is bendable to form a desired configuration. A clamp assembly is secured to the distal end of the shaft. The clamp assembly has a first jaw and a second jaw, the second jaw moveable relative to the first jaw to open or close the clamp assembly. The ablation device also includes a first electrode secured to the first jaw of the clamp assembly, a second electrode secured to the second jaw of the clamp assembly, and a handle connected to the proximal end of the shaft.

A hemostat-type device for ablative treatment of tissue, particularly for treatment of atrial fibrillation, is constructed with features that provide easy and effective treatment. A swiveling head assembly can allow the jaws to be adjusted in pitch and roll. Malleable jaws can permit curved lesion shapes. A locking detent can secure the jaws in a closed position during the procedure. An illuminated indicator provides confirmation that the device is operating. A fluid delivery system simplifies irrigated ablation procedures.

A remotely deflectable electrophysiology / ablation catheter of the type intended for placing into an interior passage of the heart is disclosed. The distal end of this elongated tubular catheter has a pair of tension / compression members each with a flattened end portion connected to the distal electrode and extending through the catheter casing and attached to a user moveable actuator for effecting the tension / compression thereon for remotely curling the distal end of the catheter. Spaced ring electrodes are provided adjacent the distal electrode. A permanent bend is pre-formed in the casing and tension / compression members adjacent the ring electrodes about an axis perpendicular to the elongated tension / compression members. Movement of the remote actuator causes the distal portion of the catheter to curl into a lariat in a plane perpendicular to the axis along the elongated catheter casing, thus permitting electrical mapping or ablation with the distal and / or ring electrodes about the inner surface of the heart passage into which the lariat is formed and situated. The lariat can achieve a curvature greater than 360 degrees and at a significantly reduced radius to allow insertion of the catheter distal end into passages of reduced dimension.

A method and apparatus for carrying our thermal ablation of target tissue is disclosed. The apparatus includes an RF ablation device having a multi-electrode electrode assembly designed to be deployed in target tissue, defining a selected-volume tissue region to be ablated, and having infusion channels for infusing a liquid into the target tissue during the ablation process. A control unit in the apparatus is operably connected to an RF energy source, for controlling the RF power level supplied to the electrodes, and to an infusion device, for controlling the rate of infusion of a liquid through the device into the tissue. During both electrode deployment and tissue ablation, impedance and or temperature measurements made within the tissue are used to control the RF source and infusion device, for optimizing the time and extent of tissue ablation.

The present invention is directed to an articulate minimally invasive surgical instrument with a flexible wrist to facilitate the safe placement and provide visual verification of the ablation catheter or other devices in Cardiac Tissue Ablation (CTA) treatments. In one embodiment, the instrument is an endoscope which has an elongate shaft, a flexible wrist at the working end of the shaft, and a vision scope lens at the tip of the flexible wrist. The flexible wrist has at least one degree of freedom to provide the desired articulation. It is actuated and controlled by a drive mechanism located in the housing at the distal end of the shaft. The articulation of the endoscope allows images of hard-to-see places to be taken for use in assisting the placement of the ablation catheter on the desired cardiac tissue. The endoscope may further include couplings to releasably attach an ablation device / catheter or a catheter guide to the endoscope thereby further utilizing the endoscope articulation to facilitate placement of the ablation catheter on hard-to-reach cardiac tissues. In another embodiment, the articulate instrument is a grasper or any other instrument with a flexible wrist and a built-in lumen to allow an endoscope to insert and be guided to the distal end of the instrument.

A method and apparatus for ablation of a layer of tissue is achieved by providing first and second bodies on opposed sides of the tissue. The first body includes a first ablation member and a source of magnetic force adjacent one side of the tissue. The second body includes a second ablation member and a magnetically attractive element responsive to the magnetic force adjacent the other side of the tissue. The magnetic attraction between the source and the attractive element is adapted to align the first and second bodies in opposed relationship on the opposed sides of the tissue. One of the first and second bodies may include at least one expandible member for controlling the magnetic attraction between the bodies.

This invention relates to a surgical device and method. More particularly, it relates to a tissue ablation device assembly and method using a circumferential ablation member in combination with a position monitoring assembly in order to position the circumferential ablation member along a circumferential region of tissue at a location where a pulmonary vein extends from a left atrium.

An articulate minimally invasive surgical instrument with a flexible wrist to facilitate the safe placement and provide visual verification of the ablation catheter or other devices in Cardiac Tissue Ablation (CTA) treatments is described. In one embodiment, the instrument is an endoscope which has an elongate shaft, a flexible wrist at the working end of the shaft, and a vision scope lens at the tip of the flexible wrist. The flexible wrist has at least one degree of freedom to provide the desired articulation. It is actuated and controlled by a drive mechanism located in the housing at the distal end of the shaft. The articulation of the endoscope allows images of hard-to-see places to be taken for use in assisting the placement of the ablation catheter on the desired cardiac tissue. The endoscope may further include couplings to releasably attach an ablation device / catheter or a catheter guide to the endoscope thereby further utilizing the endoscope articulation to facilitate placement of the ablation catheter on hard-to-reach cardiac tissues. In another embodiment, the articulate instrument is a grasper or any other instrument with a flexible wrist and a built-in lumen to allow an endoscope to insert and be guided to the distal end of the instrument.

An apparatus for transmural ablation using an instrument containing two electrodes. The electrodes extend along the surfaces of mating jaw members which are moveable between open and clamped positions. The electrodes are connected to an RF energy source so that, when activated, they are of opposite polarity. An EKG sensor is located on one of the jaw members and spaced from the electrode so that, when the electrodes are activated to form a line of ablation, the EKG sensor contacts the tissue outside the line of ablation. A pacing electrode is located on one of the jaw members so as to be on the opposite side of the line of ablation from the EKG sensor. Thus, if the line of ablation is not transmural, the EKG sensor will be able to detect signals generated by the pacing electrode.

An ablation apparatus including a maneuvering mechanism, a conductive element attached to the apparatus, a sensor attached to the apparatus and an output device in communication with the sensor is provided. The sensor senses vibration during the ablation procedure and sends a signal to the output device to reduce power to the conductive element.

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 brain, liver, cardiac, prostate, breast, and vascular tissues and neoplasms. An apparatus in accordance with the present invention includes a source of super-cooled fluid for selectively providing super-cooled fluid to the target tissue to cause a temporary cessation of cellular or electrical activity, a supply of conductive or electrolytic fluid to be provided to the target tissue, and 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 super-cooled fluid to the target tissue to cause a temporary cessation of cellular or electrical activity, evaluating whether the temporary cessation of cellular or electrical activity is the desired cessation of cellular or electrical activity, and if so, delivering a conductive fluid to the 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.

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.

Devices, systems and methods are disclosed for the ablation of tissue and treatment of cardiac arrhythmia. An ablation system includes an ablation catheter that has an array of ablation elements and a location element, an esophageal probe also including a location element, and an interface unit that provides energy to the ablation catheter. The distance between the location elements, determined by calculating means of the system, can be used by the system to set or modify one or more system parameters.

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.

Apparatus and methods are provided for determining in near realtime the position of a probe placed within a living body. Electric currents are driven between one or more electrodes on the probe and electrodes placed on the body surface. The impedance between the probe and each of the body surface electrodes is measured, and three-dimensional position coordinates of the probe are determined based on the impedance measurements. Dynamic compensation is provided for changing impedance of the body surface and its interface with the electrodes, resulting from such causes as electrode peel-off and changes in moisture and temperature. The compensation improves the accuracy of, inter alia, medical procedures, such as mapping the heart or performing ablation to treat cardiac arrhythmias.

Apparatus and methods for treating an intervertebral disc by ablation of disc tissue. A method of the invention includes positioning at least one active electrode within the intervertebral disc, and applying at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s), wherein the volume of the nucleus pulposus is decreased, pressure exerted by the nucleus pulposus on the annulus fibrosus is reduced, and discogenic pain of a patient is alleviated. In other embodiments, a curved or steerable probe is guided to a specific target site within a disc to be treated, and the disc tissue at the target site is ablated by application of at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s). A method of making an electrosurgical probe is also disclosed.

An apparatus for ablating tissue, the apparatus having first and second opposing jaws operative to compress tissue to be allayed therebetween, the first jaw having a first ablation surface directing ablative energy into the tissue and the second jaw having a second ablation surface reflecting incident ablative energy into the tissue. The ablative energy may be ultrasonic, microwave, cryoablation, radio-frequency, photodynamic, laser, and cautery energy. The instrument may also have a pointed tip for piercing tissue, allowing the instrument to clamp the tissue wall of a hollow organ before ablation. Alternately, the instrument may clamp two or more tissue layers of a hollow organ without piercing prior to clamping an ablation.

A catheter introduction apparatus provides an ultrasound assembly for emission of ultrasound energy. In one application the catheter and the ultrasound assembly are introduced percutaneously, and transseptally advanced to the ostium of a pulmonary vein. An anchoring balloon is expanded to center an acoustic lens in the lumen of the pulmonary vein, such that energy is converged circumferentially onto the wall of the pulmonary vein when a transducer is energized. A circumferential ablation lesion is produced in the myocardial sleeve of the pulmonary vein, which effectively blocks electrical propagation between the pulmonary vein and the left atrium.

According to the present invention, a catheter having at least one multi-purpose lumen formed through the catheter terminates proximal a relatively complex-shaped distal portion thereof. In one form of this embodiment, the relatively complex-shaped distal portion comprises a looped portion having diagnostic- and / or ablation-type electrodes coupled thereto and an elongated diameter-adjusting member coupled proximal the distal end of the looped portion. The multi-purpose lumen may be used to alternately accommodate a variety of dedicated materials; such as, (i) a guide wire for initial deployment or later repositioning of the catheter, (ii) a volume or flow of a contrast media and the like, (iii) a deployable hollow needle or tube and the like used to biopsy adjacent tissue or dispense a therapeutic agent into a volume of tissue, and (iv) a cooling fluid, such as saline solution and the like dispensed at least during therapeutic tissue ablation procedures.

Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter which has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition.

A catheter introduction apparatus provides an optical assembly for emission of laser light energy. In one application, the catheter and the optical assembly are introduced percutaneously, and transseptally advanced to the ostium of a pulmonary vein. An anchoring balloon is expanded to position a mirror near the ostium of the pulmonary vein, such that light energy is reflected and directed circumferentially around the ostium of the pulmonary vein when a laser light source is energized. A circumferential ablation lesion is thereby produced, which effectively blocks electrical propagation between the pulmonary vein and the left atrium.

A tissue ablation device has a handle and an ablation head coupled to the handle. The ablation head has a first jaw, a second jaw, and an ablative element coupled to at least one of the first and second jaws. A thickness measurement device may be coupled to the ablation device to indicate the distance separating the first and second jaws. Further, a force measurement device may be coupled to the ablation device to measure the force being applied by the first and second jaws to a piece of tissue. Further, a strain measurement device may be coupled to the ablation device to indicate the strain resulting in a piece of tissue disposed between the first and second jaws when a stress is applied to the tissue.

Apparatus and methods for treating an intervertebral disc by ablation of disc tissue. A method of the invention includes positioning at least one active electrode within the intervertebral disc, and applying at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s), wherein the volume of the nucleus pulposus is decreased, pressure exerted by the nucleus pulposus on the annulus fibrosus is reduced, and discogenic pain of a patient is alleviated. In other embodiments, a curved or steerable probe is guided to a specific target site within a disc to be treated, and the disc tissue at the target site is ablated by application of at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s). A method of making an electrosurgical probe is also disclosed.

An electrophysiology catheter and method of use for mapping and ablation procedures. The catheter includes a braided conductive member at its distal end that can be radially expanded. The catheter can be used in endocardial and epicardial mapping and ablation procedures.

Devices, systems, and methods for treating atherosclerotic lesions and other disease states, particularly for treatment of vulnerable plaques, can incorporate optical coherence tomography or other imaging techniques which allow a structure and location of an eccentric plaque to be characterized. Remodeling and / or ablative laser energy can then be selectively and automatically directed to the appropriate plaque structures, often without imposing mechanical trauma to the entire circumference of the lumen wall.

A system and method for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the impedance of the tissue to be ablated. Rather than attempting to detect a desired drop or a desired increase impedance, completeness of a lesion is detected in response to the measured impedance remaining at a stable level for a desired period of time, referred to as an impedance plateau. The mechanism for determining transmurality of lesions adjacent individual electrodes or pairs may be used to deactivate individual electrodes or electrode pairs, when the lesions in tissue adjacent these individual electrodes or electrode pairs are complete, to create an essentially uniform lesion along the line of electrodes or electrode pairs, regardless of differences in tissue thickness adjacent the individual electrodes or electrode pairs.

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.

A catheter which may be configured as a loop during an ablation procedure, and a method of use for such a catheter, are disclosed. According to one aspect of the present invention, an ablation catheter includes a flexible distal member arranged to inserted into a first vessel in the body of a patient, and an elongated flexible tubular member with a distal portion which is coupled to a proximal portion of the flexible distal member. The elongated flexible tubular member has a flexibility that is greater than or equal to the flexibility of the flexible distal member. The catheter also includes a transmission line which is at least partially disposed within the elongated flexible tubular member. A proximal end of the transmission line is suitable for connection to an electromagnetic energy source. The catheter further includes a transducer that is coupled to the transmission line, and is arranged to generate an electric field sufficiently strong to cause tissue ablation. In one embodiment, a distal portion of the flexible distal member is arranged to protrude from a second vessel of the body of the patient while at least part of the elongated flexible tubular member is located in a cardiac chamber of the heart of the patient.

An ablation apparatus system for treating tissues in a patient, the ablation apparatus comprising temperature sensing means for measuring a temperature, wherein said temperature sensing means comprises a temperature sensing probe and at least one temperature sensing wire secured to the temperature sensing probe; force measuring means for measuring force exerted onto the temperature sensing probe by a tissue; and RF current generating means for generating RF current, wherein the RF current generating means is connected to and controlled by the temperature sensing means and force measuring means, adapted for supplying RF current to the temperature sensing probe as an electrode for tissue treatment.

An ablation instrument having a flexible portion at or near the distal portion of the instrument, is provided. The instrument includes an elongated tubular member having a steerable distal end configured to deflect, or otherwise direct, and properly position at least a portion of the distal portion, comprising an ablation device, during an ablation procedure. The instrument further includes a deflectable member which cooperates with the steering system allowing for the proper placement of the ablation device adjacent or proximate to the target tissue surface. The steering system may alternatively be incorporated into a separate guiding catheter as part of the catheter system.