RETRIEVABLE MEDICAL FILTER WITH DIVERSE BASKETS
An elongated medical filter is radially expandable and compressible and is intended for placement inside a tubular body passage, such as a blood vessel, of a patient. In expanded form, the medical filter has a spine with a retrieval element and a pair of longitudinally spaced filter baskets, one of the filter baskets having a plurality of independent legs and the other of the filter baskets having a plurality of legs with interconnecting struts.
1 . A radially expandable and compressible, elongated medical filter having a longitudinal axis, said filter intended for placement inside a tubular body passage of a patient and comprising in expanded form:
(A) a spine extending along the longitudinal axis of the filter and having a retrieval element at one end thereof;
(B) a first filter basket attached to said spine and comprising a plurality of discrete legs with free ends; and
(C) a second filter basket attached to said spine longitudinally spaced from said first filter basket and comprising a plurality of legs with free ends and further with interconnecting struts extending between the legs.
2 . The medical filter of claim 1 wherein at least some of the legs of one of the first and second filter baskets have reentrantly bent end segments.
3 . The medical filter of claim 1 wherein the first filter basket is attached to the spine proximate to the retrieval element while the second filter basket is attached to the spine distal to the retrieval element.
4 . The medical filter of claim 1 wherein said retrieval element is a hook.
5 . The medical filter of claim 1 wherein said second filter basket is secured to a longitudinal end of said spine.
6 . The medical filter of claim 1 wherein said second filter basket is secured to said spine at a point spaced longitudinally from said first filter basket.
7 . The medical filter of claim 1 , wherein said filter is comprised of Nitinol.
8 . The medical filter of claim 1 wherein said filter is comprised of stainless steel.
9 . The medical filter of claim 1 wherein each of said legs has a segment extending generally parallel to the longitudinal axis of said filter.
10 . The medical filter of claim 1 wherein said legs are comprised of wire.
11 . The medical filter of claim 1 wherein said legs are cut from tubing.
12 . The medical filter of claim 1 wherein first filter basket is attached to the spine distal to the retrieval element while the second filter basket is attached to the spine proximal to the retrieval element.
13 . A radially expandable and compressible, elongated medical filter having a longitudinal axis, said filter intended for placement inside a tubular body passage of a patient and comprising in expanded form:
(A) a spine extending along the longitudinal axis of the filter and having a retrieval hook at one end thereof;
(B) a first filter basket attached to said spine proximal to said retrieval hook and comprising a plurality of discrete legs, each leg having one end secured to said spine and a free end; and
(C) a second filter basket attached to said spine distal to said retrieval hook and longitudinally spaced from said first filter basket and comprising a plurality of legs, each of said legs having one end secured to said spine and a free end, and further comprising a plurality of interconnecting struts extending between the legs proximate to said ends connected to said spine.
14 . The medical filter of claim 13 wherein said filter is comprised of Nitinol.
15 . The medical filter of claim 13 wherein said filter is comprised of stainless steel.
16 . The medical filter of claim 1 wherein said legs are comprised of wire.
17 . The medical filter of claim 1 wherein said legs are cut from tubing.
18 . A radially expandable and compressible, elongated medical filter having a longitudinal axis, said filter intended for placement inside a tubular body passage of a patient and comprising in expanded form:
(A) a spine extending along the longitudinal axis of the filter and having a retrieval hook at one end thereof;
(B) a first filter basket attached to said spine distal to said retrieval hook and comprising a plurality of discrete legs, each leg having one end secured to said spine and a free end; and
(C) a second filter basket attached to said spine proximal to said retrieval hook and longitudinally spaced from said first filter basket and comprising a plurality of legs, each of said legs having one end secured to said spine and a free end, and further comprising a plurality of interconnecting struts extending between the legs proximate to said ends connected to said spine.
19 . The medical filter of claim 18 wherein said filter is comprised of Nitinol.
20 . The medical filter of claim 18 wherein said filter is comprised of stainless steel.
21 . The medical filter of claim 18 wherein said legs are comprised of wire.
17 . The medical filter of claim 18 wherein said legs are cut from tubing.