[Comparative morphofunctional characteristics of arterial blood vessels of the different kidney segments in humans].

The arterial blood vessels of 26 kidneys of people of both sexes at the first period of mature age were studied. Using Doppler renal investigation of superior segmental and anterior inferior segmental arteries in color duplex scan mode and multislice computed tomographic angiography, intravital investigation of 20 kidneys were performed. Corrosion casts of the renal vasculature of 6 kidneys, obtained at autopsy, were studied using scanning electron microscopy. It was shown that in kidneys with a single renal artery, anterior inferior and superior segments have a similar level of blood supply--when quantitative parameters of hemodynamics of these renal segments were compared, no significant differences were detected; in fact, no differences were found in the angioarchitectonics of anterior inferior and superior segments. In both segments, initial signs of age involution were found in the form of appearance of individual deformed glomeruli and some rarefaction of capillary network in the renal medulla.

[State of cerebral circulation in patients with essential arterial hypertension].

In order to evaluate the volumetric flow rate of the blood in the major extracranial arteries, as well as to assess intracranial haemodynamics in patients presenting with isolated arterial hypertension and those with haemodynamically insignificant pathologies of the "CA" the authors analysed the findings obtained in a total of 159 patients (71 males and 88 females) who were diagnosed with mild, moderate and severe arterial hypertension. The average age of the patients amounted to 59 +/- 12 years. Studying the thickness of the intima-medial complex of the common carotid artery in both isolated arterial hypertension (AH) andAH combined with atherosclerotic alterations in the CA demonstrated its thickening, which was more evident in a combination of atherosclerosis with AH. The study revealed a decrease in the volumetric flow rate ofthe blood in all extracranial vessels, as well as that of the total volumetric flow rate in the group ofpatients with isolated AH and especially those with a combination of AH and atherosclerosis. The patients sufferingfrom both isolated AH and a combination of AH with pathological alterations of/in the carotid arteries demonstrated alterations in the flow-rate indices and an increase in the indices of the peripheral resistance in the arteries of the circle of Willis, which were mostly pronounced in those with a prolonged history of AH. A trend towards a decrease in the indices of the flow-rate of the bloodstream and an increase in the indices of the peripheral vascular resistance in hypertensive patients is determined by structural alterations in the vascular wall of the extracranial arteries on the one hand, and by the development of hypertensive microangiopathy, on the other.

[Clinical, structural-functional and haemodynamic correlates of cerebral venous blood circulation disturbances].

Difficulties of liquor circulation as a result of cerebrospinal fluid absorption and venous drainage of the entire intracranial space, in particular in the presence of venous system abnormalities in the forms of hypoplasia or aplasia of venous sinuses, play an essentiale role in cerebral venous dyscirculation. The symmetric character of hydrocephaly in chronic insufficiency of cerebral blood circulation and strong dependence of chronic cerebrovascular insufficiency on passive congestion suggest that the latter is characteristic of the blood supply system in whole. The MPI analysis of 120 patients revealed signs of cerebral ischemic lesions in 72% of cases, i.e. dilatation of liquor-containing spaces, multiple lacunar infarctions, especially in deep brain regions, diffusive changes of the periventricular white matter etc. Low indices of the blood flow increase during antiorthostatic loading, a trend towards decreasing of PI parameters and difficulty of blood flow in conditional insonation of intracranial veins in cases of "pseudotumorous syndrome" in patients with clinical signs of passive congestion. Venous dilatation of convexital brain areas and intensification of contrasting of direct sinus and vein of Galen were observed in venous infarctions.

[Cerebral venous hemodynamics in chronic disorders of cerebral circulation].

The aim of the work was to assess extra- and intracranial venous hemodynamics in patients with circulatory disorder-induced encephalopathy (DE). Altogether 114 DE patients were examined. There were 46 women and 68 men aged 43 to 78 years (mean age 59.6+/-12.5 years). As dependent on the clinical manifestations the patients were distributed into groups: stage 1 DE was present in 36 patients, stage 2 DE in 47>> and stage 3 DE was identified in 31 patients. 82.78% of the examined had arterial hypertension (AH), the mean standing of which accounted for 9.7+/-7.2 years. The control group accrued 36 practically normal persons aged 36 to 62 years (mean age 47.6+/-11.3 years). All the patients were provided standard neurologic examination, magnetic resonance tomography (MRT) of the brain with venography of the brachiocephalic veins and venous sinuses of the brain, Color Doppler Imaging of the extracranial vessels, and transcranial Doppler. The patients complained primarily of headache, dizziness, instability and staggering on walking, memory and work fitness decrease, and irritability. Atherosclerotic plaques which were primarily homogeneous (types IV and V according to the classification by Geroulakos et al., 1993) were identified in the carotid arteries in 76 (62%) patients. In 48 (42%) patients, stenoses were bilateral. Hemodynamically significant (>50%) stenoses were present in 42 (34%) persons. In most cases, the patients showed dilatation of the jugular veins and a mean reduction of the flow intensity to 14+/-8.1 cm/s as compared to the control group (20.6+/-11.3 cm/s). The tendency toward flow intensity lowering associated with its phasic nature disorder was particularly well-defined in patients with stage 3 DE and a long-term history of AH. On examination of the parameters of cerebral venous circulation the patients with stage 1 DE tended to the rise of the linear flow velocity (LFV) in the basal veins of Rozenthal and in the direct sinus. However, no significant changes in the PI parameters were recorded. In the patient group with stages 2 and 3 DE, there was an appreciable rise of the LFV in the deep veins in the presence of a remarkable PI lowering (the flow velocity in the vein of Rozenthal 21.8+/-7.2 cm/s in stage 2 DE, and 24.4+/-7.2 cm/s in stage 1 DE). In 87 (79%) cases, MRT revealed the signs of diffuse ischemic lesion of the brain. Fifty-five (48%) patients were diagnosed to have leukoarayos whereas in 48 (42%) cases, there were identified multiple lacunar infarctions, primarily of the deep cerebral segments. Ten (8%) patients demonstrated type 1 Arnold-Chiari abnormalities -- hypoplasia of the large cerebral cistern and 4 patients had porto-cerebellar atrophy (megacysterna magna). Analysis of the MRV revealed, in the majority of cases (in 67 or 59%), developmental abnormality of the drainage system of the brain. Thus, 42 (37%) patients were diagnosed to have hypoplasia of one of the transverse sinuses (of the right one in 23 cases and of the left one in 19 cases); 17 (15%) persons had aplasia of the transverse sinus. Eight patients showed hypoplasia of the sigmoid sinuses (of the right one in 5 cases and of the left one in 3 cases). In all the cases of developmental abnormalities of the venous sinuses, there was a compensatory dilatation of the contralateral sinus and in some cases, there were visualized the upper and lower sinuses, the identification of which in health is difficult. So, atherosclerosis of AH-induced lesion of the brachiocephalic arteries interferes with the action of the physiological "arteriovenous pump" thereby provoking venous congestion. Progression of the process is associated with depletion of the compensatory adaptive potentialities of the collateral venous outflow which (especially in concomitant developmental abnormality in the region of the posterior cranial fossa and venous sinuses) favours aggravation of venous circulatory distress, the rise of the CSF pulse pressure and the emergence of benign intracranial hypertension and hydrocephalus followed by cerebral atrophy.

[The status of carotid arteries and the main vascular risk factors in cerebral infarctions of "anterior circulation"]. / Sostoianie sonnykh arterii i osnovnye sosudistye risk faktory pri infarktakh mozga "perednei tsirkuliatsii".

The aim of the work was to examine the degree of carotid stenosis, the structure of atherosclerotic plaques, and the predominance of the main vascular risk factors in patients with multiple lacunar and comparatively large "non-lacunar" cerebral infarctions. A study WAS made of the data on 110 patients (mean age 62.5 years) with multiple cerebral infarctions revealed by MRT and with stenoses of the internal carotid artery (ICA) of varying degrees of severity. Minor lacunar infarctions (LI) were present in 62 cases whereas comparatively large "non-lacunar" infarctions (NLI) in 48 cases. All the patients underwent standard neurologic examination, laboratory analyses, MRT of the brain with angiography (MRA) of the extra-intrecrania1 vessels, transcranial Doppler (TCD), and examination of the heart for revealing the cardioembolic nature of cerebral infarctions. Among patients with both LI and NLI, arterial hypertension was the most frequently occurring risk factor in 53 (85%) and 35 (73%) patients respectively. In the study groups, there were no appreciable differences in the incidence of high hematocrit, hyperfibrinogenemia, tobacco-smoking, and diabetes mellitus. Patients with NLI demonstrated hypercholesterolemia, CAD and atherosclerosis of the peripheral vessels significantly more often (p<0.05). In the patient group with NLI, hemodynamically significant stenoses of the ICA were predominant: in 18 (37.5%) patients, they were moderate, in 12 (25%) critical, and 7 (14.6%) patients had occlusions whereas in LI, the portion of critical stenoses and ICA occlusions was cooperatively low - in 11 (17.7%) and in 5 (8.1%) patients respectively. Both groups showed the thickening of the complex of the medial CCA layer. Ultrasonopraphy of the vessels has revealed that in patients with NLI and LI, there predominated potentially embologenic plaques, namely in 69% and in 53% of cases, respectively. Our investigations allow to assume that arterial hypertension is the most frequently occurring risk factor of cerebral infarction (both minor lacunar and large "non-lacunar"). Factors such as CAD, hypercholesterolemia, DM, hemorheological disorders, end tobacco-smoking are likely to have an unfavorable impact on both general and cerebral hemodynamics as well as on the microcirculatory bed whereby being on the whole important risk factors of cerebral infarction. Hemodynamically significant stenoses, especially critical ones, occlusions, and embologenic plaques of the ICA are pathogenetically closely linked with the development of "non-lacunar" cerebral infarctions. At the same time they, under certain conditions, may become the cause of multiple lacunar cerebral infarctions.

[Effect of atherogenic risk factors on the state of complex intima-media of common carotid artery]. / Vliianie riada aterogennykh faktorov riska na sostoianie kompleksa intima-mediia obshchei sonnoi arterii.

AIM: To elucidate relationship between presence of atherogenic risk factors (dyslipidemia, hypertension, smoking, etc.) and common carotid artery intima-media thickness. MATERIAL AND METHODS: Color duplex carotid artery scanning and determination of blood lipids, lipo- and apolipoproteins were carried out in 160 patients aged 34-73 (mean 57.4+/-8.2) years. RESULTS: Dyslipidemia, hypertension (diastolic blood pressure > or = 95 mm Hg), smoking and intima-media thickness > 1 mm were present in 57, 49, 54 and 65% of patients, respectively. Intima-media thickness increased with age and in the presence of hypercholesterolemia, hypertension and smoking. Significant (p<0.05) correlations existed between intima-media thickness and levels of total cholesterol (r=0.512), triglycerides (r=0.411), apolipoprotein B (r=0.497), high density lipoprotein cholesterol (r=-0.404), apolipoprotein-A1 (r=-0.386), duration of hypertension (r=0.488). CONCLUSION: Ultrasound study of intima-media thickness allowed to assess harmful effect of various atherogenic risk factors (mechanical - hypertension, biochemical - dyslipidemia, toxic - smoking) on the state of arterial wall.