AIMS: @entity64 caused by hemodynamically significant internal @entity2998 stenoses and occlusions are believed to be embolic or hemodynamic of origin. The aim of the study was to assess cerebral hemodynamic compromises of significant @entity2998 stenosis of occlusion using vasodilatory testing ( @entity3791 test) in asymptomatic and symptomatic @entity1 . @entity1 AND METHODS: 36 @entity1 with unilateral, hemodynamically significant @entity543 were investigated using transcranial Doppler @entity3791 -test. There were 12 asymptomatic and 24 symptomatic @entity1 . The middle cerebral artery mean blood flow velocity was measured at rest and after intravenous injection of 1 g @entity3791 . The absolute mean blood flow velocities and the cerebrovascular reactivity was compared at the stenotic and non-stenotic side. In a further analysis the mean velocities and the cerebrovascular reactivity values of the stenotic side were compared. Results of @entity3791 test performed on 28 healthy volunteers were used as control values. RESULTS: There were no side-differences between the middle cerebral artery mean blood flow velocity and cerebrovascular reactivity values in the asymptomatic group. In the symptomatic group, however middle cerebral artery mean velocity and cerebrovascular reactivity after @entity3791 was significantly lower on the stenotic side, than on the non-stenotic one. Comparing the different groups non-stenotic sides did not differ to each other in their cerebral blood flow velocity and cerebrovascular reactivity. In the symptomatic @entity1 , however, cerebral blood flow velocity and cerebrovascular reserve capacity after @entity3791 was lower, than that of the stenotic side of asymptomatic @entity1 and controls. CONCLUSIONS: The transcranial Doppler is a suitable method for detecting altered cerebral hemodynamics in significant @entity543 . Impaired cerebrovascular reactivity may refer to the impairment of cerebral autoregulatory mechanisms.

[Assessment of cerebrovascular reactivity in XXXX with symptomatic and asymptomatic atherosclerotic @entity2998 lesions].

@entity1 :: ('9606', 'Species') :: ['patients', 'PATIENTS'] @entity64 :: ('MESH:D020521', 'Disease') :: ['Strokes'] @entity3791 :: ('MESH:D000086', 'Chemical') :: ['acetazolamide'] @entity2998 :: ('MESH:D002340', 'Disease') :: ['carotid artery'] @entity543 :: ('MESH:D016893', 'Disease') :: ['carotid stenosis']
@entity1 :: (9606,Species) :: ['patients']
