[en] Intracranial arterial vasospasm resulting from subarachnoid hemorrhage is associated with a high incidence of morbidity and mortality. A new microballoon device has now been developed for intraluminal angioplasty, enabling these spastic vessels to be dilated. This balloon is composed of a new type of silicone elastomer that provides enhanced elongation while maintaining a soft low-tension shell. When inflated within blood vessel, it will elongate and conform to the vessel contour, without causing rupture. The authors have treated 36 vascular territories in 13 patients with this new balloon device. In each case, they have been able to dilate the blood vessel to normal luminal diameter, with angiographic evidence or improved perfusion. The indication, techniques, and results from angioplasty of spastic intracerebral arteries are presented