The evaluation of the hemodynamically significant stenosis of the carotid arteries: analyzing the results from the duplex scanning of vessels, from the computed tomographic and the transcatheter X-ray contrast angiography

Background: Atherosclerotic stenosis of the carotid arteries is one of the main reasons of stroke, of transient ischemic attacks, of developing cognitive disorders and of incapacitating the population. The key indication to invasive treatment for this disease is the degree of stenosis in the carotid artery, due to which the most important problem in the diagnostics is the maximally precise evaluation of the stenosis degree. The duplex scanning of the carotid arteries is a safe, non-invasive and relatively inexpensive visualization method, which is the first line of diagnostics. The precision of measuring the stenosis and the occlusion of the carotid artery, according to the ultrasound examination data, varies from 70% to 90%. At the same time, the degree of stenosis, measured using various methods, does not always match. AIM: to compare the data obtained by duplex scanning of the brachiocephalic arteries and by other instrumental diagnostics methods in terms of the precision of measuring the percentage of stenosis in the carotid arteries, as well as to analyze the reasons of discrepancies between the obtained data. METHODS: The research is based on the retrospective analysis of case history data from the patients hospitalized to the Vascular Surgery Department of the Federal State Budgetary Institution «Federal Scientific and Clinical Center» under the Russian Federal Medical-Biological Agency during the period from 01.05.2023 until 20.05.2024. The obligatory inclusion criteria for the analysis were the presence of the main disease of the I65 group according to the ICD-10 and undergoing at least one of the examination types within the settings of the FSBI «Federal Scientific and Clinical Center» under the Russian Federal Medical-Biological Agency (duplex scanning, computed tomographic angiography, transcatheter X-ray contrast angiography). The statistical processing was done using the Statistica software pack version 10.0 (StatSoft). RESULTS: The conducted research has shown that there is no complete matching between the data from the transcatheter X-ray contrast angiography, the computed tomographic angiography and the duplex scanning. The analysis of the reasons of discrepancies when measuring the degree of stenosis in the orifices of the internal carotid arteries from the results of duplex scanning and computed tomographic angiography has allowed for isolating three main groups: the human factor (operator-dependent, 30.4%), the anatomic factor (23.2%) and the differences in descriptions (46.4%). CONCLUSION: Upon examining the patients, it is necessary to strictly follow the algorithm of diagnosing the stenoses of the carotid arteries, beginning from the duplex scanning of the extracranial segments of brachiocephalic arteries as the most accessible and highly informative method. Computed tomographic angiography of this vascular segment is required for selecting the patients for surgical treatment, for it is necessary to keep in mind the potential risk of developing the contrasted nephropathy and the risks of radiation exposure. A properly done ultrasound examination allows for not only decreasing the number of discrepancies between these two diagnostic methods, but also to avoid the necessity of conducting such an invasive radio-contrasting method as angiography.