Detachable multidiameter vasoocclusive coil

Abstract

A vasoocclusive helical coil having a proximal end that carries a coupling member for attaching the coil to the distal end of a wire and a proximal winding that has a smaller diameter than adjacent windings whereby the proximal end of the coil is positioned radially inwardly of the main body of the coil.

1 . A helical vasoocclusion coil for use with a wire having a distal end, said coil having: 
 (a) a proximal end adapted to detachably couple to the distal end of the wire;    (b) a distal end;    (c) a first diameter intermediate (a) and (b); and    (d) a second diameter smaller than said first diameter at said proximal end whereby said proximal end is positioned radially inwardly of said first diameter.    
   
   
       2 . The coil of  claim 1  wherein the second diameter is also at the distal end of the coil whereby the distal end of the coil is also positioned radially inwardly of said first diameter.  
   
   
       3 . The coil of  claim 1  wherein said proximal end has a coupling member that detachably interlocks with the distal end of the wire.  
   
   
       4 . An assembly for use in occluding a vessel or a cavity within a vessel comprising: 
 (a) an elongated wire having a distal end that carries a first coupling member; and    (b) a helical vasoocclusion coil having: 
 (i) a proximal end that carries a second coupling member that is detachably coupled to the first coupling member;  
 (ii) a distal end;  
 (iii) a first diameter intermediate (i) and (ii); and  
 (iv) a second diameter smaller than said first diameter at said proximal end whereby the first coupling member is positioned radially inwardly of said first diameter.  
   
   
   
       5 . The assembly of  claim 4  wherein the second diameter is also at the distal end of the coil whereby the distal end of the coil is also positioned radially inwardly of said first diameter.