A case is presented of basilar artery aneurysm, to which endovascular treatment was applied, employing the mechanical detachable system (MDS) of tungsten spirals. The aim of the study was to demonstrate spiral disappearance in embolised aneurysm without recanalisation, following a long-term follow-up period — up to 42 months. During the years 1994 to 1999, about 100 intracranial aneurysms and carotid-cavernous fistulas were embolised by the use of MDS spirals. In one case, spiral disappearance was noted, that event not, however, affecting the patient's state in any way and confirmed by clinical and radiological evaluations.
