6300 results about "Lesion" patented technology

A tissue ablation catheter for forming a lesion along a substantially circumferential region of tissue is described. The catheter includes one or more sensors for monitoring the temperature of the tissue being ablated. The temperature sensors are mounted on the interior or exterior of an expandable member that is affixed to a shaft of the catheter.

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.

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.

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.

The invention provides an apparatus and system for ablation of body structures or tissue in the region of the rectum. A catheter is inserted into the rectum, and an electrode is disposed thereon for emitting energy. The environment for an ablation region is isolated or otherwise controlled by blocking gas or fluid using a pair of inflatable balloons at upstream and downstream locations. Inflatable balloons also serve to anchor the catheter in place. A plurality of electrodes are disposed on the catheter and at least one such electrode is selected and advanced out of the catheter to penetrate and ablate selected tissue inside the body in the region of the rectum. The electrodes are coupled to sensors to determine control parameters of the body structure or tissue, and which are used by feedback technique to control delivery of energy for ablation or fluids for cooling or hydration. The catheter includes an optical path disposed for coupling to an external view piece, so as to allow medical personnel to view or control positioning of the catheter and operation of the electrodes. The catheter is disposed to deliver flowable substances for aiding in ablation, or for aiding in repair of tissue, such as collagen or another substance for covering lesions or for filling fissures. The flowable substances are delivered using at least one lumen in the catheter, either from at least one hole in the catheter, from an area of the catheter covered by a microporous membrane, or from microporous balloons.

MicroRNA genes are highly associated with chromosomal features involved in the etiology of different cancers. The perturbations in the genomic structure or chromosomal architecture of a cell caused by these cancer-associated chromosomal features can affect the expression of the miR gene(s) located in close proximity to that chromosomal feature. Evaluation of miR gene expression can therefore be used to indicate the presence of a cancer-causing chromosomal lesion in a subject. As the change in miR gene expression level caused by a cancer-associated chromosomal feature may also contribute to cancerigenesis, a given cancer can be treated by restoring the level of miR gene expression to normal. microRNA expression profiling can be used to diagnose cancer and predict whether a particular cancer is associated with an adverse prognosis. The identification of specific mutations associated with genomic regions that harbor miR genes in CLL patients provides a means for diagnosing CLL and possibly other cancers.

Disclosed is a cartilage repair product that induces both cell ingrowth into a bioresorbable material and cell differentiation into cartilage tissue. Such a product is useful for regenerating and/or repairing both vascular and avascular cartilage lesions, particularly articular cartilage lesions, and even more particularly mensical tissue lesions, including tears as well as segmental defects. Also disclosed is a method of regenerating and repairing cartilage lesions using such a product.

A system for forming linear lesions in tissue, the system comprising a control unit having an ultrasound vibration driving section, and an ultrasonic applicator operatively connected to the control unit. The ultrasonic applicator comprises an ultrasonic transducer having an acoustic window, and an ultrasonic vibratory element, the ultrasonic vibratory element having a convergent shape with a focus located in the direction of the acoustic window. An air gap is adjacent to the ultrasonic vibratory element in an opposite direction from the focal point. The system further comprises means for controlling the depth of the lesion formed in the tissue.

An automated method and/or system for identifying suspected lesions in a brain is provided. A processor (a) provides a magnetic resonance image (MRI) of a patient's head, including a plurality of slices of the patient's head, which MRI comprises a multispectral data set that can be displayed as an image of varying pixel intensities. The processor (b) identifies a brain area within each slice to provide a plurality of masked images of intracranial tissue. The processor (c) applies a segmentation technique to at least one of the masked images to classify the varying pixel intensities into separate groupings, which potentially correspond to different tissue types. The processor (d) refines the initial segmentation into the separate groupings of at least the first masked image obtained from step (c) using one or more knowledge rules that combine pixel intensities with spatial relationships of anatomical structures to locate one or more anatomical regions of the brain. The processor (e) identifies, if present, the one or more anatomical regions of the brain located in step (d) in other masked images obtained from step (c). The processor (f) further refines the resulting knowledge rule-refined images from steps (d) and (e) to locate suspected lesions in the brain.

A device for diagnosis and treatment of tumors and lesions within the body. A cannula adapted to apply suction through the lumen of the catheter to the tumor or lesion is described. The lumen has a self sealing valve through which a cryoprobe is inserted while the suction is being applied. The cryoprobe is then inserted into the lesion, and operated to ablate the lesion.

A system 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.

Excitation light for normal light observation with wavelengths in the visible spectrum, which is output from a lamp, and excitation light with wavelengths in the infrared spectrum for exciting a fluorescent substance characteristic of being accumulated readily in a lesion are irradiated simultaneously to a living tissue, to which the fluorescent substance has been administered, through an endoscope. Fluorescence components are separated from light stemming from the living tissue by means of a separator such as a dichroic mirror, introduced to a first imaging device, and then imaged. Light components with wavelengths in the visible spectrum are introduced to a second imaging device and then imaged. Signals representing the images are subjected to signal processing, whereby a video signal is produced. For better diagnosis, two images are displayed while, for example, one of the images is superimposed on the other.

A surgical device integrating a suction mechanism with a coagulation mechanism is provided for improving lesion creation capabilities. The device comprises an elongate member having an insulative covering attached about means for coagulating soft tissue. Openings through the covering expose regions of the coagulation-causing elements and are coupled to lumens in the elongate member which are routed to a vacuum source. A fluid source to passively transport fluid along the contacted soft tissue surface may be provided in order to push the maximum temperature deeper into tissue.

A wire control catheter for aligning and guiding a guide wire through a lesion in a vessel is provided. The wire control catheter includes a shaft having a guide wire lumen and a control wire lumen. A control wire passes through the control wire lumen and is used in combination with an articulation structure to deflect or curve a distal tip portion of the catheter. The distal catheter shaft may include a centering device for centering the catheter within the vessel. The distal catheter shaft also may include a pre-dilation balloon for dilating the lesion prior to performing angioplasty or other treatment on the lesion. Additionally, a sliding sheath catheter may be used to provide additional support to the guide wire. The sliding sheath catheter is sized to fit within the guide wire lumen of the control catheter and to allow the guide wire to pass through it. A method of treatment of a blood vessel includes inserting a guide wire into the blood vessel and advancing a control catheter over the guide wire until the distal tip of catheter is near the occlusion in the blood vessel. The tip of the catheter then is deflected via a control wire and an articulation structure. The guide wire is then advanced across the occlusion. The control catheter also may be advanced across the occlusion simultaneously with the guide wire or subsequent to the guide wire crossing. Prior to crossing the occlusion, the wire control catheter may be centered using a centering device. Subsequent to crossing the occlusion, the occlusion may be pre-dilated with a pre-dilation balloon of the wire control catheter.

A catheter assembly and method for treatment of cardiac arrhythmia, for example, atrial fibrillation, by electrically isolating a vessel, such as a pulmonary vein, from a chamber, such as the left atrium. The catheter assembly includes a catheter body and at least one electrode. The catheter body includes a proximal portion, an intermediate portion and a distal portion. The intermediate portion extends from the proximal portion and defines a longitudinal axis. The distal portion extends from the intermediate portion and forms a substantially closed loop transverse to the longitudinal axis. The at least one electrode is disposed along the loop. With this configuration, the loop is axially directed into contact with the chamber wall about the vessel ostium. Upon energization, the electrode ablates a continuous lesion pattern about the vessel ostium, thereby electrically isolating the vessel from the chamber.