Abstract: The present invention is directed to a needle control handle which allows a needle extension distance to be adjusted, set and locked. In one embodiment, the control handle has an outer body and a piston adapted for relative longitudinal movement to extend the needle. A first control knob is movable on the piston for adjusting and setting the distance of the needle extension. A second knob is provided for releasably locking the first control knob on the piston once the needle extension distance has been set. Each of the knobs has a contact surface that enables the knobs to mutually lock with and release from each other.

Abstract: An irrigated tip electrode design includes a shell generally surrounding a plug which jointly define a chamber that is fed with fluid by a lumen. The fluid is distributed to the outer surface of the tip electrode through fluid passages. The chamber is advantageously isolated from a region of the tip electrode occupied by electrical and/or electromagnetic components in the tip electrode. Lumens occupied by the these components terminate in blind holes that have no communication with the chamber. A method of fabricating includes providing a shell configured from a rod to provide an open interior cavity, sealing and partially filling the cavity with a plug to form a chamber, then forming fluid passages between the cavity and an outer surface of the tip electrode, and providing a lumen through which fluid can enter the chamber and exit therefrom through the fluid passages.

Abstract: A method for position tracking includes using first and second field generators located at respective different first and second locations to generate respective first and second magnetic fields in a vicinity of first and second objects. The first and second fields are measured using first and second position sensors respectively associated with the first and second objects. First and second potential relative coordinates of the first object relative to the second object are calculated responsively to the first and second magnetic field. The potential relative coordinates are processed in order to determine a correct relative coordinate of the first object relative to the second object.

Abstract: A medical probe includes a flexible insertion tube, having a distal end for insertion into a body cavity of a patient, and a distal tip, which is disposed at the distal end of the insertion tube and is configured to be brought into contact with tissue in the body cavity. A coupling member couples the distal tip to the distal end of the insertion tube and includes a tubular piece of an elastic material having a helical cut therethrough along a portion of a length of the piece.

Abstract: A mapping and ablation catheter with contact force sensing capabilities at a distal end, includes a catheter body, a deflectable section, and a tip distal section which has a tip electrode and a contact force sensor for sensing a 3D contact force vector applied to the tip electrode. In contact with the tip electrode, the contact force sensor has a body and has at least one sensor with an electrical characteristic that is responsive to deformation of the body resulting from force vector. The sensor is adapted to receive an electrical current and to output an electrical signal indicative of a change in the electrical characteristic. In one embodiment, the sensor is a strain gage responsive to tension and compression of at least a portion of the body of the force sensor and the electrical characteristic of the strain gage that is monitored is electrical resistivity.

Abstract: An irrigation ablation probe comprises a generally rigid probe body and a handle mounted to the proximal end of the probe body. The generally rigid probe body comprises an ablation electrode at its distal end having at least one irrigation opening through which fluid can pass. An infusion tube extends through the probe body for introducing fluid into the ablation electrode. The irrigation ablation probe is useful for treating atrial fibrillation during open heart surgery.

Abstract: A dilator having a retractable needle is disclosed. The dilator includes an elongated dilator body having a proximal end, a distal end and at least one lumen longitudinally extending therethrough. A handle is mounted at the proximal end of the dilator body, and a control button is moveably connected to the outside of the handle. The needle extends through the lumen and has a distal end comprising a needle tip section. An arm attached the control button to the needle. Distal movement of the control button causes the needle to move from a retracted position, wherein the needle tip is disposed within the lumen of the dilator body, to a protruding position, wherein the needle tip protrudes beyond the distal end of the dilator body.

Abstract: A system and method that enable real-time optical measurements of tissue reflection spectral characteristics while performing ablation, involves the radiation of tissue and recapturing of light from the tissue to monitor changes in the reflected optical intensity as an indicator of steam formation in the tissue for prevention of steam pop. The system includes a catheter adapted to collect light reflected from tissue undergoing ablation, a detection component that identifies and separates constituent wavelengths of collected light, a quantification apparatus for generating measured light intensity data for the collected light, and a processor that analyses the measured light intensity data in relation to time. The system may include a graphical display and/or an audio output (e.g., speaker) that provide visual and/or audio alarm when the system infers formation of a steam pocket in the tissue.

Abstract: A catheter that provides bi-directional steering and allows for deflection sensitivity adjustment includes a catheter body, a deflectable tip section and a control handle, wherein the control handle has a deflection member adapted for user manipulation, a deflection assembly responsive to the deflection member to draw on a tensile puller member for deflecting the tip section, and an adjustment mechanism adapted to adjust sensitivity of the deflection member. The adjustment mechanism also correspondingly adjusts a maximum degree of deflection of the tip section. The deflection assembly includes a rotatable pulley arm and two pulleys, and a deflection sensitivity adjustment mechanism with a cam device that varies a separation distance between the pulleys.

Abstract: A method for attaching a ring electrode to the shaft of the tip section of a catheter comprises passing an electrode lead wire through a lumen in the catheter and out an exit hole in the tip section. The portion of the electrode lead wire extending out of the exit hole is stripped of non-conductive coating and wrapped around the shaft and secured in a clove hitch arrangement. The wrapped electrode lead wire is pulled tight while the material of the shaft is heated to embed the electrode lead wire in the shaft so that its outermost surface is generally flush with the surface of the shaft. The exit hole is sealed and a ring electrode, having a flared skirt is slipped over the shaft to a position over the wrapped electrode lead wire and exit hole. It is then swaged to reduce its outer diameter to about that of the outer diameter of the shaft of the tip section to thereby create a low ohmic connection with the electrode lead wire.

Abstract: A catheter for measuring electrical activity and ablating tissue is provided. The catheter comprises an elongated generally-tubular catheter body. A non-retractable electrode assembly is mounted at the distal end of the catheter body. The electrode assembly comprises a generally tubular ablation electrode formed of a material having shape-memory having a generally straight exposed region and at least one irrigation port in the exposed region through which fluid can pass from the inside to the outside of the ablation electrode. The exposed region is generally transverse to the catheter body. The electrode assembly further comprises a tip at the distal end of the electrode assembly comprising a generally ball-shaped exposed region. First and second distal mapping electrodes are mounted distal to the exposed region of the ablation electrode. At least the first distal mapping electrode, and optionally the second distal mapping electrode, is incorporated into the generally ball-shaped exposed region of the tip.

Abstract: Using specialized cardiac catheters for image acquisition, features of the heart are readily identifiable on an ultrasound image, based on a previously generated electrical activation map of the heart. The electrical activation map is automatically registered with the ultrasound image using information obtained from position sensors in the catheters. Features identifiable on the electrical activation map, presented as points, tags, design lines, and textual identification, are projected into the plane of the ultrasound fan and overlaid on the ultrasound image, thereby clarifying the features that are visible on the latter.

Abstract: A catheter enables real-time light measurements, for example, without limitation, diffuse reflectance, fluorescence, etc., from biological materials, such as tissue (including blood), while performing RF ablation. The catheter tip design isolates illumination and collection paths such that light exits the catheter tip and travels through the tissue of interest (e.g., cardiac tissue or blood) before returning to the catheter tip. Such a design advantageously avoids saturation of the optical detector, and ensures diffusion of the illumination light within the medium of interest. The catheter has a catheter body and a tip electrode. The tip electrode has an exterior shell, an inner layer of diffuse material and a hollow cavity, wherein the inner layer is configured to transmit light outside the tip electrode to a tissue via a set of illumination openings in the shell wall and the hollow cavity is configured to receive light from the tissue via a set of collection openings in the shell wall and the inner layer.

Abstract: A catheter for diagnosing or treating the vessels found within a body or body space includes a center strut that is bonded, preferably thermally, along its longitudinal axis with the thermoplastic tubular member within which it is housed. The tubular member preferably has three layers: an inner layer, a braided layer and an outer layer. The composite catheter is made using a process in which two half-cylinder shaped mandrels are placed on each side of the center strut while the strut is heated in order to cause the thermal bonding. The bonded center strut provides in-plane deflection and improved transfer of torque to the tip of the catheter.

Abstract: Methods and systems for cable inspection operate by generating a relative motion between an electrical cable including multiple wires and a magnetic field. An electrical signal induced in the wires is measured responsively to the magnetic field. A variation in the electrical signal is sensed due to the relative motion. In response to the variation, a defect is detected in the electrical cable.

Abstract: A method for tracking a position of an object includes using a field sensor associated with the object to measure field strengths of magnetic fields generated by two or more field generators, wherein a measurement of at least one of the field strengths is subject to a distortion. Rotation-invariant location coordinates of the object are calculated responsively to the measured field strengths. Corrected location coordinates of the object are determined by applying to the rotation-invariant location coordinates a coordinate correcting function so as to adjust a relative contribution of each of the measured field strengths to the corrected location coordinates responsively to the distortion in the measured field strengths.

Abstract: An injection catheter for infusing therapeutic and diagnostic agents into the heart is provided. The injection catheter comprises a catheter body comprising a flexible tubing having proximal and distal ends and at least one lumen therethrough. A tip section comprising a flexible tubing having proximal and distal ends is mounted at the distal end of the catheter body. A needle control handle is provided at the proximal end of the catheter body. An injection needle extends through the tip section, catheter body, and needle control handle and has a proximal end attached to the needle control handle and a distal end within the tip section. The injection needle is longitudinally slidable within the tip section so that its distal end can extend beyond the distal end of the tip section upon suitable manipulation of the needle control handle.

Abstract: Using specialized cardiac catheters for image acquisition, features of the heart are readily identifiable on an ultrasound image, based on a previously generated electrical activation map of the heart. The electrical activation map is automatically registered with the ultrasound image using information obtained from position sensors in the catheters. Features identifiable on the electrical activation map, presented as points, tags, design lines, and textual identification, are projected into the plane of the ultrasound fan and overlaid on the ultrasound image, thereby clarifying the features that are visible on the latter.

Abstract: Methods and systems are provided for wirelessly powering a medical device in a living subject using external radiofrequency energy. A radiofrequency driving unit outside the subject irradiates the medical device. A passive antenna is positioned outside the subject, generally opposing the driving unit to redirect the field generally toward the device. The reradiating element increases uniformity of the electromagnetic field produced by the driving unit, which reduces local tissue heating in the subject and in personnel attending the subject.

Abstract: Catheters and methods for epicardial ablation are provided. A suitable catheter comprises an elongated catheter body and an ultrasound transducer mounted at or near the distal end of the catheter body. The transducer has a front surface and an opposing back surface, wherein the transducer is positioned to transmit ultrasound energy toward tissue facing the front surface but not toward tissue facing the back surface. A sensor is mounted within the catheter near the ultrasound transducer for sensing a location and an orientation of the ultrasound transducer within a patient. A suitable method involves introducing the distal end of the catheter introducing into the pericardium of a patient. The transducer's front surface is positioned so that it generally faces tissue to be ablated, and the tissue is ablated with ultrasound energy generated by the transducer.