THE EFFECT OF CAROTID ENDARTERECTOMY ON CEREBRAL BLOOD-FLOW AND CEREBRAL BLOOD-VOLUME STUDIED BY SPECT

The aim of our work was to study the state of regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) in patients with different degree of carotid stenosis after CE. Thirty six patients wi th carotid stenosis aged 46-65 years (mean age 55 years) were studied. In all the patients before and one month after carotid endarterectomy (CE) single photon emission computed tomography (SPECT) with Tc-99m-h examethylpropylene amine oxime (Tc-99m-HMPAO, Ceretec, Amersham) and S PECT with labelled in vivo Tc-99m-red blood cells (Tc-99m-RBC) were ca rried out. According to the results of scintigraphic studies the regio nal cerebral blood flow (rCBF, ml/min/100g), the volume of hypoperfusi on (Vhypoperf, sm(3)), the stroke volume (SV, sm(3)), the interhemisph eric ratio of rCBF (IRrCBF) and the regional cerebral blood volume (rC BV, ml/100g) were calculated. CE leads to the bilateral increase of ce rebral perfusion especially at the side of more expressed damage putti ng away interhemisphere asymmetry of rCBF. After CE the regression of SV and Vhypoperf. were revealed. In asymptomatic disease patients with monolateral stenosis of carotid arteries rCBF reaches normal values a nd regions of hypoperfusion are not revealed. Surgical recanalization of carotid arteries causes expressed changes of scintigraphic paramete rs of rCBV : normalization of initially increased values of rCBV in pa tients with asymptomatic development of stenosed atherosclerosis of ca rotid arteries and subsequent increase of rCBV in comparison with preo perative level in patients who underwent acute stroke with neurologica l deficit and patients with poor clinical signs and multiple damage of both internal carotid arteries.