ABSTRACT
The current evidence shows that STA-MCA bypass does not prevent recurrent stroke better than medical treatment alone in patients with symptomatic carotid artery occlusion in general (8). Whether or not the EC/IC bypass confers benefit in a subgroup of patients with clinical or technical evidence for a hemodynamically compromised hemisphere on the side of the carotid artery occlusion remains as yet unknown. Many studies have reported the improvement of cerebral hemodynamic measurements after STA-MCA bypass operation (34-37) but comparisons with similar patients who were not operated on are not available. Others found that improvement of hemodynamic measures did not occur after operation (38) or was not consistent (39,40). Improvement of hemodynamic measures has been shown especially in patients in whom such measures were most disturbed before operation (41-43). A caveat is that improvement of cerebral blood flow shortly after STA-MCA bypass surgery may not last over time (42,44) and that cerebral hemodynamic measures may improve spontaneously (22,26,45).
