| 摘要 |
<p>Apparatus and methods for removal of obstructive material from a stent by modified electrosurgical ablation; penetrating and steering a catheter through an obstructed lumen, and detecting objects within a body via electromagnetic detection. An electrosurgical device (10) having at least one electrode (14) is positioned within the stent (20), and current is supplied to the electrode (14) to ablate material within or around the stent (20). The device may be properly positioned within the stent by using ultrasound transducers, fiber optics, impedance sensing or otherwise. In another aspect, by ablating material asymmetrically and advancing a catheter into (1010) the resulting void, the catheter (1010) can be steered through occlusive material (1060). Further, a device (2010) may be inserted within the body of a patient to determine the presence and location of an electromagnetically detectable object within the body.</p> |
