A medical device comprising a compressed, inflatable, detachable single-lobed metal balloon attached to a catheter and methods of use for occluding blood vessels or treating vascular aneurysms are disclosed. The balloon can be made with ductile metals such as gold, platinum, or silver so that the balloon will conform to the shape of the void space during inflation and so that the balloon can be subsequently shaped by the application of an external force. The balloon can be configured such that it can be de - tached from the catheter by physical means or by electrolysis. The surface of the balloon can be configured to promote the growth of tissue into the wall of the balloon and to release drugs or pharmacologically active molecules, so that vessel occlusion or the sealing of an aneurysm will be maintained over time.
