A percutaneous catheter system for use within the human body and an ablation catheter for ablating a selected tissue region within the body of a subject. The percutaneous catheter system can include two catheters that are operatively coupled to one another by magnetic coupling through a tissue structure. The ablation catheter can include electrodes positioned within a central portion. The ablation catheter is positioned such that the central portion of a flexible shaft at least partially surrounds the selected tissue region. Each electrode of the ablation catheter can be activated independently to apply ablative energy to the selected tissue region. The ablation catheter can employ high impedance structures to change the current density at specific points. Methods of puncturing through a tissue structure using the percutaneous catheter system are disclosed. Also disclosed are methods for ablating a selected tissue region using the ablation catheter.

A catheter is responsive to external and internal magnetic field generators for generating signals representing position and pressure data, with a reduced number of sensing coil leads for minimizing lead breakage and failure. The catheter includes a flexible joint with pressure sensing and position coils, at least pair of a pressure sensing coil and a position coil are serially connected. Methods of calibrating a catheter for position and pressure sensing, and detecting magnetic field interference with one catheter by another catheter or other metal or ferrous object advantageously use signals between two sets of sensors as a “back up” or “error check”.

A flow directed device adapted to be guided by a fuid, such as blood, flow within a tubular structure such as a blood vessel is disclosed, said device comprising a proximal end (100), a distal end (101) and an elongated body (102) in between defining a longitudinal axis (103), characterized in that said distal end (101) comprises a ferromagnetic area or structure (300) capable of deflecting the distal end (101) when subjected to an external magnetic field. A system comprising the device, as well as method of use of the device, are also disclosed.

An apparatus includes a shaft, the shaft including a plurality of stepped sections along the length of the shaft. The apparatus further includes a plurality of electrodes disposed along the length of the shaft, each electrode characterized by a geometric aspect ratio of the length of the electrode to the outer diameter of the electrode. Each electrode is located at a different stepped section of the plurality of stepped sections of the shaft and includes a set of leads. Each lead of the set of leads is configured to attain an electrical voltage potential of at least about 1 kV. The geometric aspect ratio of at least one electrode of the plurality of electrodes is in the range between about 3 and about 20.

The application is directed to devices and methods where one or more magnetic or magnetizable implants provides therapeutic benefits to a patient. The implant may be useful for expanding the range of motion of joints or dynamically providing different responses to changing conditions in the body where the implant is placed. An electromagnet is placed on or in a bone on one side of a joint, and another electromagnet or magnetically active material is placed on or in a bone on the opposing side of the joint. The electromagnet may be continuously energized to relieve pressure in the joint space, or may be energized in response to forces applied to the joint.

An MR compatible steerable sheath is provided. The MR compatible steerable sheath includes a steerable shaft that receives first and second longitudinal movement wires at a distal end thereof and audible or tactile means for indicating to a user the degree of deflection of the distal tip of the steerable shaft. A control handle is coupled to a proximal end of the first and second longitudinal movement wires and causes longitudinal movement of the wires.

A magnetic guidance system (20) for guiding a guidewire (70) or other elongate medical device includes a magnet unit (20) disposed in one implementation adjacent a head end of a patient table (30). The magnet unit is disposed on a magnet support which enables the magnet unit (20) to move in a periodic motion substantially around a single plane. The preferred motion is a rotary motion about a patient's head, which creates a repetitive repulsive force at the distal end of the medical device, causing the distal end of the medical device to move in different directions within the patient's vasculature, useful in assisting the guidance of the medical device through tortuous vessel structures. The repetitive alternating medical field makes guidance of a medical device within a patient's vasculature a relatively simple task.

A system for receiving signals from a magneto-mechanical oscillator includes a main coil array adapted to receive a response signal of the magneto-mechanical oscillator and to transmit an excitation signal to the magneto-mechanical oscillator, and an additional coil for receiving a signal of the magneto-mechanical oscillator. A localizer is adapted to localize the additional coil and comprises a controller for controlling the main coil array and the additional coil such that a received localization signal is generated, a sensitivity provider for providing sensitivity information, and a processor for determining a position and/or orientation of the additional coil based on the provided sensitivity information and based on the received localization signal. A kit is provided for upgrading a system with a main coil array, by adding one or more additional coils and providing software for locating the one or more additional coils with the use of a pilot tone transmission.

An apparatus for emitting a field comprising a a core, a conductive winding with a first end, a second end, and an intermediate portion, where the conductive winding surrounds a portion of the core and is wound about a winding axis, a protrusion for aligning the apparatus where the protrusion is parallel with the winding axis, and a conductive connector extending from the conductive winding, wherein the conductive connector is electrically coupled with the conductive winding at the intermediate portion.

A guidance system utilizes ultrasound imaging or other suitable imaging technology. In one embodiment, the guidance system includes an imaging device including a probe for producing an image of an internal body portion target, such as a vessel. One or more sensors may be associated with the probe. The system may include a medical device, such as a needle, separate from the probe, the medical device having a magnetic field associated therewith. The system may include a processor that uses data relating to the magnetic field sensed by the one or more sensors to determine a position and/or orientation of the medical device. The system may also include a display that shows an image of the internal body portion target taken by the ultrasound imaging probe and a depiction of the medical device positioned and/or oriented with respect to the image.