New microballoon device for transluminal angioplasty of intracranial arterial vasospasm.

A new microballoon device has been developed to treat intracranial arterial vasospasm by transluminal angioplasty. The balloon is composed of a unique silicone elastomer that will elongate and conform to the blood vessel lumen, thereby decreasing the risk of vessel rupture. The balloon device, which can be either flow-directed or catheter-guided, is permanently affixed to a 2.0-French microcatheter and introduced from a transfemoral arterial approach. Two balloon sizes are currently available. The smaller-sized balloon, used in most cases, measures 0.85 x 3.50 mm uninflated, will accept a volume of 0.10 ml, and will expand to 3.5 x 12.5 mm. The larger balloon, used in six of 14 cases, measures 1.5 x 3.9 mm uninflated, accepts a volume of 0.50 ml, and expands to 7.5 x 13.5 mm. In clinical trials, this device has been successful in dilating both focal and diffuse areas of vasospasm in multiple territories. Thus far, 40 vascular territories have been successfully treated in 14 patients 15-73 years old. In each case, there was angiographic evidence of successful dilatation, and in 10 patients (71%), clinical improvement in the neurologic condition. Transluminal angioplasty techniques may be useful for reversing some of the serious neurologic sequelae associated with acute intracranial arterial vasospasm.