[Cerebral circulation in chronic hypertensive encephalopathy].

Cerebral blood supply was studied in 123 patients with stage III hypertensive encephalopathy (HE) in the absence of occlusion of main head arteries. Duplex scanning was used to measure blood flow rate in common carotid (CCA), vertebral (VA) and medial cerebral (MCA) arteries. Cortical cerebral blood flow (CBF) was measured by single-photon emission CT using 99mTc- ceretec. Normal and stable blood flow in CCA and VA was documented at all HE stages whereas it decreased in MCA of patients with HE II-III. Cortical CBF in frontal and parietal segments in HE II-II was higher than in HE I (p < 0.05). These findings suggest impaired subcortical perfusion and correlation of the discrepancy between cortical and subcortical blood supply with the severity of HE. Leukoaraosis is an indicator of hypoperfusion.

[Possibility of an emission computer tomography for an estimation cerebral perfusion at patients with carotid stenoses before and after stenting].

THE PURPOSE: To estimate possibilities for studies of cerebral perfusion with brain scintigraphy for revealing and an estimation of features of change brain perfusion at patients with a cardio-cerebral vascular pathology before and after carotid stenting (CAS). MATERIAL AND METHODS: 11 patients with established (after carotid angiography) stenosis of internal carotid artery and coronary artery disease have been studied with SPECT with analogue HMPAO teoxim--Tc99M after intravenous introduction 700 MBk up to and in 5 days and in the remote period after stenting. For analysis of results the program "Neurogam" have been used. Standartized perfusion maps have been created. RESULTS: Before performing CAS various variants of the image cerebral perfusion maps have been obtained: from diffuse insignificant reduction in both hemispheres of a brain up to the regions hypoperfusion, characteristic for ischemic changes. Regions of hypoperfusion on the side opposite to a stenosis or occasion were revealed. SPECT, performed after cas on 5th day or after 2-3 months found increase of general brain perfusion, disappearance of symmetric both asymmetric regions hypoperfusion and reduction of a degree local hypoperfusion on the side of stenting. CONCLUSIONS: Maps of brain perfusion before and after CAS adequately reflect microcirculation of a brain with local changes of perfusion. Use of perfusion parameters gives possibility to estimate changes of brain perfusion before and after CAS in patients with combined carotid and coronary pathology.

[Cerebral hemodynamics and endothelium function in patients with cerebrovascular pathology treated by teveten].

Teveten (eprosartan mesilate) was used as a monotherapy or in combination with hypotiazide (12,5 mg/day) in dosage 600 mg once a day for treatment of 20 patients with cerebrovascular pathology (chronic cerebrovascular insufficiency, consequences of brain ischemica in the presence of arterial hypertension stage I-II, or higher borderline levels of normal blood pressure (BP). Treatment duration was 12 weeks, 24-h monitoring of BP was made some indices of cerebral blood flow, hemodynamics and peripheral vessels reaction were registered. Modulating antihypertensive effect of Teveten was found, statistically significant reduction of systolic BP did not result in worsening of cerebral hemodynamics. Moreover, there was an improvement of endothelial function. Therefore, teveten may be recommended for treatment of patients with cerebrovascular pathology both with arterial hypertension and higher borderline BP.

[Cerebral perfusion in patients with arterial hypertension and chronic forms of brain vascular pathology]. / Tserebral'naia perfuziia u bol'nykh arterial'noi gipertoniei i s khronicheskimi formami sosudistoi patologii golovnogo mozga.

AIM: To examine cerebral perfusion in patients with dyscirculatory encephalopathy and residual disorders of cerebral circulation in arterial hypertension. MATERIAL AND METHODS: Duplex scanning of extra- and intracranial arteries, computed tomography of the head were performed in 26 hypertensive patients with chronic vascular pathology of the brain. Cerebral perfusion was studied by the evidence obtained at single-photon emission computed tomography. RESULTS: Impaired segmental perfusion of the brain, primarily of frontal and temporal location, was detected in 88.5% patients. Occlusive lesions of extra- and intracranial arteries were accompanied by significant deterioration of the perfusion while visualization of leukoaraosis was associated with high perfusion in the anterior frontal compartments indirectly pointing to defects in autoregulation of cerebral circulation. It was found that different correlations exist between perfusion of various segments of the brain and systemic arterial pressure. This is explained by functional and hemodynamic heterogenicity of different brain regions. CONCLUSION: Specific features of cerebral perfusion in patients with chronic forms of vascular brain pathology should be considered in planning antihypertensive therapy because of the risk of focal hypoxia and even ischemia in an inadequate fall of arterial pressure.

[Regional cerebral blood flow and the infarct volume in obstruction of the internal carotid artery in relationship to the source of the collateral circulation]. / Regionarnyi mozgovoi krovotok i ob''em infarkta pri zakuporke vnutrennei sonnoi arterii v sootnoshenii s istochnikom kollateral'nogo krovoobrashcheniia.

The cerebral blood flow was examined by means of Obrist's 133Xe-inhalational method, cerebral angiography, and computer-aided tomography of the head in 100 patients with occlusion of the internal carotid artery. The findings obtained have revealed a correlation between the level of the compensatory collateral blood supply of the bed of the middle cerebral artery (MCA) and the source of collateral blood circulation. The authors have demonstrated the vulnerability of the MCA bed secondary to a low level of blood supply persisting despite the functioning of all pathways of the collateral circulation.

[Normal values for regional cerebral blood flow using the 133Xe-inhalation method]. / Normal'nye velichiny regionarnogo mozgovogo krovotoka pri ispol'zovanii 133Xe-ingaliatsionnogo metoda.

Using the 32-detector system and the inhalation method after W. Obrist, the authors determined normal values of the regional cerebral blood flow (RCB) in 20 healthy subjects. The method demonstrated good reproducibility which warrants its wide clinical application for RCB determination for studying the pathogenetic mechanisms of cerebral blood flow changes.