| 摘要 |
An intravascular catheter especially designed to surgically remove atheromas or other forms of stenotic or thrombotic lesions from the interior walls of a blood vessel using an RF discharge between two bipolar electrodes is described. Affixed to the distal end of an elongated, flexible, plastic, tubular member is a bipolar electrode structure comprising a cylindrical insulator having a first conductive metal ring electrode surrounding the periphery of that insulator. Projecting from the distal end of the cylindrical insulator is a second, frusto-conical shaped member whose major base is slightly less in diameter than the diameter of the cylindrical insulator. An insulative material covers all but the distal side edge of the first ring electrode and an annular zone of the second electrode located immediately adjacent to the exposed distal side edge of the first electrode. Wires running through the lumen of the tubular member couple the first and second electrodes to an RF generator coupled to the catheters's proximal end. When appropriately energized, an intense current flow path is created between the exposed electrode surfaces for cutting through the blood vessel obstruction. The cone shaped member is rotatable about an axis which is eccentric to the centerline of the cylindrical insulator and by manually manipulating a torquing wire or tube at its proximal end, the electrode gap can be varied to control the location where cutting occurs. A motor device may also be used to continuously rotate the torquing wire.
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