BACKGROUND AND PURPOSE: Current transcranial Doppler criteria for @entity2553 after @entity510 are not age specific. We analyzed the effect of age on cerebral blood flow velocity changes after @entity510 and constructed an age-adjusted predictive model of cerebral blood flow velocity in @entity510 @entity1 . METHODS: We identified @entity1 with @entity510 admitted between 1991 and 1999 with a prospective transcranial Doppler database. Eighty-one @entity1 , with complete medical records and transcranial Doppler examinations of the vessels of interest, were included. @entity1 were subdivided into 2 groups by age: younger, <68 years of age (n=47) and older, >/=68 years of age (n=34). Maximum mean flow velocity and incidence of symptomatic @entity2553 were reported. Linear and nonlinear regression analyses were performed. RESULTS: Middle cerebral artery and internal carotid artery mean flow velocity were lower in older @entity1 (median 76 versus 114 cm/s and 76 versus 126 cm/s, respectively; P<0.003). Incidence of symptomatic @entity2553 was lower in older @entity1 (44% versus 66%; P=0.05). Older @entity1 developed symptomatic @entity2553 at lower middle cerebral artery (median 57 versus 103 cm/s; P=0.04) and internal carotid artery (median 54 versus 81 cm/s, P=0.02) mean flow velocity. Relationship between middle cerebral artery and internal carotid artery mean flow velocity and age was quadratic (ANOVA, P<0.0001). CONCLUSIONS: Older @entity1 have a lower incidence of symptomatic @entity2553 , and such @entity2553 develops at lower cerebral blood flow velocity than younger @entity1 . A quadratic relationship was found between age and cerebral blood flow velocity. This model could be used to create an age-adjusted nomogram that might improve diagnostic capabilities of transcranial Doppler.

Effect of age on cerebral blood flow velocity and incidence of XXXX after @entity510 .

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients'] @entity2553 :: ('MESH:D020301', 'Disease') :: ['vasospasm'] @entity510 :: ('MESH:D013345', 'Disease') :: ['aneurysmal subarachnoid hemorrhage', 'subarachnoid hemorrhage']
@entity2553 :: (MESH:D020301,Disease) :: ['vasospasm']
