'A STENT, AND A METHOD FOR THE TREATMENT OF AN ANEURYSM IN AN INTRACRANIAL VESSEL'

摘要

A stent for use in a method for the treatment of an aneurysm (3) in an intracranial vessel (5) comprises an expandable framework (7) and a film (22) formed thereon by spraying, sputtering, dipping or the like of a polymer material. The stent comprises a central bridging portion (25) for bridging and closing the aneurysm (3) and first and second non-bridging portions (26) and (27). First communicating openings (29a) extend through the film (22) in the central bridging portion (25) and communicate with a central diverting bore (17) extending longitudinally through the framework (7) for accommodating blood flow therethrough to the aneurysm (3). Second communicating openings (29b) extending through the first and second non-bridging portions (26) and (27) accommodate blood flow from the diverting bore (17) to side vessels (30) and perforators (31 ) extending from the vessel (5) at respective opposite ends of the aneurysm (3). The area of the first communicating openings (29a) is less than the area of the second communicating openings (29b). The spacing between the first communicating openings (29a) is greater than the spacing between the second communicating openings (29b) so that blood flow is considerably restricted to the aneurysm (3), while normal blood flow is maintained to the side branches (30) and perforators (31).