A clinical case of visual function preservation in hemodynamically significant stenosis of the internal carotid artery

This article presents a review of the literature on the causes and mechanisms of the discrepancy between the degree of narrowing of the internal carotid artery and the severity of visual impairment. A clinical case of preserved visual function in a patient with hemodynamically significant stenosis of the internal carotid artery is presented. The relevance of this study is due to the fact that the degree of stenotic damage to the main arteries of the head does not always correspond to the severity of clinical manifestations in the organ of vision, which complicates the prediction of the functional state of the visual analyzer. Particular attention is paid to the results of a comprehensive ophthalmological examination and an assessment of the vascular bed of the brachiocephalic arteries. This observation demonstrates that even with severe stenotic damage to the internal carotid artery, high visual function can be preserved and significant structural and functional changes in the visual analyzer can be absent. The data obtained demonstrate the important role of individual compensatory mechanisms in maintaining adequate perfusion of the ocular tissues and optic nerve. The results of the study expand our understanding of the mechanisms of preservation of visual functions in pathology of the carotid arteries and confirm the importance of collateral circulation in maintaining the functional capacity of the visual analyzer.

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