Clinical Significance of Internal Carotid Artery Dolichoarteriopathy

This observational study aims to investigate the clinical significance of internal carotid artery dolichoarteriopathy, including tortuosity, kinking, and coiling, and to identify factors associated with cerebral dysfunction and adverse cerebrovascular outcomes. The study combines retrospective clinical data with prospective follow-up of patients with verified internal carotid artery dolichoarteriopathy. Anatomical, hemodynamic, neuroimaging, clinical, cognitive, and biomarker characteristics will be evaluated to develop and validate a multimodal approach to risk stratification. Outcomes will also be compared between patients managed surgically and conservatively according to routine clinical indications. Treatment decisions are made independently by the treating physicians and are not assigned by the study protocol.

Inclusion Criteria: * Age 18 to 75 years, inclusive. * Verified pathological deformation of the internal carotid artery, including tortuosity, kinking, and/or coiling, confirmed by duplex ultrasound and/or angiographic imaging. * Ability to undergo baseline clinical and neurological assessment and longitudinal follow-up. * Written informed consent for participation and processing of personal data. Separate optional consent may be obtained for storage of residual biospecimens and genetic testing, where applicable. Exclusion Criteria: * Acute ischemic or hemorrhagic stroke within 6 months before planned enrollment if the participant's condition prevents valid baseline assessment or study procedures. * Complete occlusion of the study internal carotid artery or brachiocephalic trunk that prevents valid assessment of the pathophysiological role of arterial tortuosity. * Hemodynamically significant atherosclerotic stenosis of the internal carotid artery greater than 50% on the side relevant to the analysis when it represents the dominant alternative cause of impaired blood flow. * Unstable angina, NYHA class III-IV heart failure, or another decompensated cardiovascular condition that prevents safe participation. * Myocardial infarction within the previous 3 months. * Severe cognitive impairment or dementia preventing valid informed consent or neuropsychological assessment, unless participation is legally permitted through an authorized representative. * Active malignancy or systemic treatment expected to substantially affect the investigated biomarkers or prognosis. * Decompensated respiratory, renal, or hepatic disease that may substantially affect safety or interpretation of study results. * Psychiatric disorder or other condition preventing adequate communication or adherence to the study protocol.