bifurcation areas outside of the interwoven region 425 can have greater lattice density for treating an aneurysm or lesser lattice density for allowing flow to branches 15 16 of the vessel the density of the lattice for each of the disclosed occluding devices can be about 20 to about 80 of the surface area of its occluding device in an embodiment the lattice density can be about 20 to about 50 of the surface area of its occluding device in yet another embodiment the lattice density can be about 20 to about 30 of the surface area of its occluding device a typical occluding device having sixteen strand braids with 0 005 inch wide ribbon 30 picks per inch ppi number of crosses points of contact per inch and 0 09 inch outer diameter has approximately 30 of lattice density surface covered by the ribbon in the embodiments disclosed herein the ribbon can be about 0 001 inch thick with a width of between about 0 002 inch to about 0 005 inch in an embodiment the ribbon has a thickness of about 0 004 inch for a 16 strands ribbon that is about 0 001 inch thick and about 0 004 inch wide the coverage for 50 ppi 40 ppi and 30 ppi will have 40 32 and 24 approximate surface coverage respectively for a 16 strands ribbon that is about 0 001 inch thick and about 0 005 inch wide the coverage for 50 ppi 40 ppi and 30 ppi will be about 50 40 and 30 approximate surface coverage respectively in choosing a size for the ribbon.