The vasoocclusive coil may be formed from a variety of materials including, but not limited to, one or more strands of a metal or metal alloy such as stainless steel or a nickel-titanium alloy, which may include a radiopaque strand, made of platinum, tungsten or gold, in order to serve as a marker, polymeric material such as a shape memory polymer, for example, and coils coated with one or more th