Abstract:

Introduction: pathological tortuosity of internal carotid arteries (ICA) is widespread; its frequency in population varies within 18-34%. Currently, there are several approaches for the determination of indications for surgical intervention in pathological ICA tortuosity. The main criteria are hemodynamic changes in the arterial flow and the presence of neurological symptoms, so an informative preoperative examination is an integral part in treatment strategy determination in patients' subsequent treatment.

Aim: was to estimate the condition of carotid arteries and substance of the brain in isolated pathological tortuosity and in combination with stenotic lesions, based on results of CT angiography.

Materials and methods: we analyzed results of examination and treatment of 70 patients. Ultrasound and CT angiography of brachiocephalic arteries were performed on a Philips iCT 256-slice multislice computed tomograph. During CT angiography, a non-contrast study, arterial and venous phases of contrast enhancement were performed with an intravenous bolus injection of 50.0 ml of isoosmolar iodinated contrast-agent at 4-5 ml/sec.

Patients were divided into two groups: patients with isolated pathological carotid tortuosity (28 pts) and patients with a combination of carotid tortuosity and stenotic lesions (42 pts). We assessed the effect of carotid tortuosity on the severity of the brain tissue alterations using statistical analysis.

Results: a lesser severity of changes in the substance of the brain was noted in patients in the group with isolated pathological tortuosity of ICA. In 9 cases, we did not detect focal lesions; in 15 cases, small foci of microangiopathy and individual cerebrospinal fluid cysts were noted, in 4 patients, we noted areas and zones of cystic-glial changes. S- and C-shaped deformation became the most frequent variants of tortuosity; the formation of 3 saccular aneurysms (two true and one false) was revealed.

Manifestations of ischemic damage of the brain substance in the group of patients with a combination of ICA tortuosity and stenotic lesion were more pronounced. Thus, in 11 cases, zones and areas of cystic-glial changes were determined within the framework of past cerebrovascular accidents; in 20 patients, foci of microangiopathy expressed in varying degrees, as well as individual cerebrospinal fluid cysts, were noted. In 11 cases, no focal lesions were detected in the brain.

Statistical processing showed a correlation between the condition of carotid arteries and the presence of focal brain damage - in the group with combination of pathological tortuosity and stenosis of ICA, more pronounced chronic ischemic brain damage was detected (p=0,012).

Conclusion: CT-angiography was noted to be highly informative in assessment of condition of carotid arteries and brain substance in patients with isolated pathological tortuosity, as well as in combination with a stenotic lesion of internal carotid arteries. With a combination of pathological tortuosity and a stenosis in internal carotid arteries, data were obtained on a more pronounced damage of the brain substance. According to computed tomography, clinical manifestations of chronic cerebrovascular insufficiency were generally more pronounced compared to changes in the brain substance. However, there was a correlation between the increase in the degree of chronic cerebrovascular insufficiency and the aggravation of the state of the brain substance.

Abstract:

Aim: was to develop a compleх ultrasound assessment of atherosclerotic plaque instability in correlation with morphological evaluation.

Material and methods: research included 121 patients with stenosis of left/right internal carotic artery (ICA) of 50% and more (due to NASCET scale): 80 men and 41 women, mean age 56,0 years. All patients underwent standart and contrast-enhanced ultrasonic scanning (CEUS), bilateral duplex monitoring of cerebral blood flow with registration of microembolic signals (MES). All patients in period up to 3 days after hospitalization - underwent carotid endarterectomy with histological examination of atheroscleroitc plaque.

Results: analysis of relationship between ultrasound and histological characteristics showed a moderate association between the intensity of contrast agent accumulation and the degree of plaque vascularization (Cramer's V 0,529; p<<0,000;) number of lipofages (Cramer's V 0,569; p<<0,001). There were no significant differences between the degree of plaque vascularization and the degree of plaque stenosis (p<0,05). We revealed significant differences between the number of MES and the intensity of atherosclerotic plaque blood supply (<<0,001).

Discussions: intensive accumulation of contrast agent in a plaque is associated with the process of angiogenesis and inflammation, and contrast-enhanced ultrasound examination of the plaque is promising for assessing its instability and the possible risk of developing cerebral vascular complications. Neovascularization intensity detected by contrast-enhanced ultrasound is associated with the number of detected microparticles in the cerebral blood flow, and does not depend on the degree of stenosis.

Conclusions: method of comprehensive assessment using CEUS and Doppler detection of microembolic particles can be effective in stratifying the risk of possible ischemic stroke in asymptomatic patients, for optimizing indications for surgical treatment of atherosclerotic plaque, and evaluating the effectiveness of lipid-lowering and statin therapy.

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Abstract:

Acute cerebrovascular accident (CVA) is one of leading causes of death and disability in the population, both in Russia and around the world.

Aim: was to improve the effectiveness of the prevention of ischemic stroke (IS) in patients with asymptomatic stenosis of internal carotid arteries (ICA).

Materials and methods: this article is an analysis of the world literature on the subject of stroke in patients without focal or ocular symptoms (asymptomatic stenosis), medical and surgical (carotid stenting / carotid endarterectomy) correction of such stenotic lesions, postoperative complications, and the risk of stroke in the immediate and late postoperative period. We presented data on development of stroke, depending on the type of plaques, brain CT data, comorbidities in these patients, the method of surgical correction of stenosis. On the basis of international multicenter studies and experience of individual domestic and foreign clinics we performed evaluation of IS conservative anc surgical prophylaxis in this group of patients.

Results: performed analysis allowed to formulate recommendations on the tactics of treatment and examination of patients with asymptomatic internal carotid artery stenosis.

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