S. Andonova-Atanasova 1, D. Mintchev 1, M. Novakova 2, R. Georgiev 2
1 Department of Neurology, Second Clinic of Neurology,
2 Department of Radiology, University Hospital St Marina – Varna, Bulgaria
Objective: The aim of this study is to find the initial changes of brain hemodynamic using color duplex sonography and evoked potentials - brainstem auditory and visual by patients with asymptomatic ischemic disturbances of cerebral circulation.
Material and Methods: By 40 elderly individuals (mean age – 65,7 years) with asymptomatic ischemic disturbances of cerebral circulation – diagnosed with MRI of the brain, was measured a blood flow velocity (BFV) and cerebral vasomotor reactivity (CVR) in the vertebral arteries using color coded duplex sonography. MRI was done at the beginning of the study and at 24 months to measure the severity of white matter changes. Evoked potentials – brainstem auditory and visual were also performed and evaluated in dynamics. It was analysed the latency, configuration and amplitude of the waves.
Results: The comparative study of velocity in vertebral arteries in the patients with asymptomatic ischemic disturbances of cerebral circulation and changes in brainstem evoked potentials reveals significant correlation in comparison to the stage of MRI changes. The hemodynamics investigation reveals significant decrease of blood flow velocity in patients with stage 3 changes on MRI by patients with asymptomatic ischemic disturbances of cerebral circulation. By visual evoked potentials was obtained the statistical relevant increase of latency and decrease of amplitude of P100 wave in the same group of patients with asymptomatic ischemic disturbances of cerebral circulation.
Discussion: The findings in our study shows, that there is a correlation between initial dysfunction of cerebral blood flow velocity and evoked potentials. The study confirm the clinical impact of doppler sonography and evoked potentials by patients with asymptomatic ischemic disturbances of cerebral circulation, which can be used as objective criteria, regarding the diagnosis and therapy strategy.
Key words: asymptomatic ischemic disturbances, color coded duplex sonography, evoked potentials, MRI.