Endovascular electrolytically detachable wire for thrombus formation

A wire (10,56) for use in combination with a microcatheter (144) to form an occlusion within a vascular cavity (64), the wire comprising: a core wire (10); anda detachable elongate tip portion (56) coupled to a distal portion of the core wire (10), the tip portion extending the core wire for a predetermined lineal extent and being adapted to be positioned, in use, in the vascular cavity (64) to form an occlusion in the vascular cavity, whereby endovascular occlusion of the vascular cavity can be performed;    characterised in that the core wire (10) has a radioopaque marker (112) disposed thereon.