Methods and devices for filtering fluid flow through a body structure

• US 6,425,909 B1
• Filed: 11/04/1999
• Issued: 07/30/2002
• Est. Priority Date: 11/04/1999
• Status: Expired due to Term

• Current Assignee: Stryker Corporation
• Original Assignee: Concentric Medical, Inc. (Stryker Corporation)
• Inventors: Dieck, Martin S., Martin, Brian B.
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): Bui, Vy Q.
• Application Number:
  US09/434,585
• Time in Patent Office: 999 Days
• Field of Search: 606/200, 606/191, 606/192, 606/194, 606/198, 608/189, 604/96.01
• US Class Current: 606/200
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2002/018 made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2250/0039 differing in diameter

Abstract

An intravascular filter having a filament which expands a filter element. The filament is a coil which is stretched to reduce the diameter of the coil for introduction. The filter element is preferably biased toward the closed position and is opened by the coil when tension is released on the coil. The filament slides along the internal surface of the filter element so that the filter element may assume intermediate positions.

Claims

1. A method of filtering flow through a vessel, comprising the steps of:

providing a filter device having a wire and a filter element, the filter element being movable between a collapsed position and an expanded position, the filter element being naturally biased toward the collapsed position, the wire also having a collapsed shape and an expanded shape, the wire being tensioned to hold the wire in the collapsed shape;

introducing the filter device into a patient;

positioning the filter element at a desired location; and

advancing the wire into the filter element so that the wire expands the filter element toward the expanded position, the wire sliding against an interior surface of the filter element and being free to move relative to the filter element at all locations proximal to a distal end.

2. The method of claim 1, wherein:

the providing step is carried out with the wire forming coils in the expanded position.

3. The method of claim 1, further comprising the step of:

compressing the wire after the releasing step.

4. The method of claim 1, wherein:

the providing step is carried out with the wire wrapped around a core element, the filter element being mounted to the core element.

5. A method of filtering flow through a vessel, comprising the steps of:

providing a filter device having a wire and a filter element, the filter element being movable between a collapsed position and an expanded position, the filter element being naturally biased toward the collapsed position, the wire also having a collapsed shape and an expanded shape, the wire being tensioned to hold the wire in the collapsed shape;

introducing the filter device into a patient; and

releasing at least some tension on the wire so that the wire expands toward the expanded position and expands the filter element, the wire sliding against an interior surface of the filter element and being free to move relative to the filter element at all locations proximal to a distal end.

6. The method of claim 5, wherein:

the providing step is carried out with the wire forming coils in the expanded position.

7. The method of claim 5, further comprising the step of:

compressing the wire after the releasing step.

8. The method of claim 5, wherein:

the providing step is carried out with the wire wrapped around a core element, the filter element being mounted to the core element.