| 摘要 |
PCT No. PCT/US95/02635 Sec. 371 Date Jul. 11, 1995 Sec. 102(e) Date Jul. 11, 1995 PCT Filed Mar. 2, 1995 PCT Pub. No. WO95/23558 PCT Pub. Date Sep. 8, 1995This invention is a method for ensuring for endovascular occlusion through the formation of thrombi in arteries, veins, aneurysms, vascular malformations, and arteriovenous fistulas. In particular, it deals with a method to predictably determine the instant of electrolytic detachment of an embolic device which is introduced to and is intended to remain at the desired thrombus formation site. The invention further includes a method for delivering an embolic device and detecting its electrolytic separation. According to the present invention, DC power with AC superposition is delivered to the sacrificial link that couples a delivery member (e.g., a guidewire) to an occlusion device. The impedance (as measured by the amplitude of the superposed AC) is monitored. When a predetermined change in that impedance (or amplitude occurs), which indicates coil detachment, the DC power is interrupted to minimize or avoid further electrolysis. |
