RESUMO
We analyzed interrelations between the cerebral blood flow, cardiac output, and condition of the brain substance in 530 patients with ischemic stroke. Dependencies between the linear blood flow velocities in all arteries supplying the brain, as well as between the total volume blood flow through the internal carotid arteries and left ventricular stroke volume were revealed. The severity of atrophy was maximum in the parietal lobes (median 1.5 (1.0; 2.0)) and minimum in the occipital lobes (median 0.5 (0; 1.0)). Temporal lobes cortical atrophy significantly correlated with changes in the limbic system and in the periventricular and deep white matter; a significant weak inverse correlation of this parameter with blood flow in the middle cerebral artery was also found. Changes in the periventricular white matter (but not in deep white matter) demonstrated a significant inverse correlation with blood flow in the middle and anterior cerebral arteries.
Assuntos
Circulação Cerebrovascular , AVC Isquêmico/fisiopatologia , Lobo Occipital/fisiopatologia , Lobo Temporal/fisiopatologia , Substância Branca/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Cerebral Anterior/diagnóstico por imagem , Artéria Cerebral Anterior/fisiopatologia , Artéria Basilar/diagnóstico por imagem , Artéria Basilar/fisiopatologia , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Feminino , Humanos , AVC Isquêmico/diagnóstico por imagem , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/fisiopatologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Neuroimagem , Lobo Occipital/diagnóstico por imagem , Artéria Cerebral Posterior/diagnóstico por imagem , Artéria Cerebral Posterior/fisiopatologia , Estudos Prospectivos , Volume Sistólico , Lobo Temporal/diagnóstico por imagem , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiopatologia , Substância Branca/diagnóstico por imagemRESUMO
Doppler measurements of ocular and orbital blood flow at rest were studied using duplex ultrasonography in 30 apparently healthy adult volunteers. The following linear and calculated Doppler measurements were estimated at rest: blood flow in ophthalmic artery (OA), central retinal artery (CRA), posterior ciliary arteries, central retinal vein and superior ophthalmic vein (SOV). In 10 patients Doppler measurements of blood flow in OA, CRA SOV were estimated 5 times by 2 observers with different level of skills in ultrasonographic ophthalmologic examination. Statistic analysis showed strong correlation of linear and calculated measurements in OA, CRA and venous blood flow velocity. A number of Doppler measurements with the most significant inter- and intraobserver variation were revealed. Measurements with high reproducibility were determined. Thus, a unique technique should be performed in estimation of Doppler measurements of blood flow in ocular and orbital vessels. The velocities in the main arteries (OA, CRA) and veins (SOV) were showed to have significant strong interobserver correlation. The highest reproducibility and accuracy was revealed for maximal systolic velocity in OA and CRA and maximal velocity for cardiac cycle in SOV.