EXTENDED DURATION MEDICAL FILTER

摘要

A medical filter for placement inside a body passage such as a vessel has a first filter half and a second filter half each of which have generally longitudinally extending legs with free ends. The first filter half has a docking station centrally located at one longitudinal end and a stop carried by one of said legs centrally located at its other end while the second filter half has a cylindrical collar and a longitudinally centrally located hook. The filter halves fit together with legs in interlocking relationship and the docking station has a smaller diameter than the diameter of the collar so that the filter can be retrieved by pushing the first filter half into the collar of the second filter half with a mandrel pushing against the docking station while holding the second filter half with a snare attached to its hook to collapse the first filter half in the collar of the second filter half and then pulling the second filter half into the lumen of a retrieval catheter with the snare.