The Predictive Value of Retinal Vascular Signs for Intracranial Artery Stenosis (RVS-ICAS)

Study Overview
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Brief Summary
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Intracranial artery stenosis (ICAS) is a leading cause of ischemic stroke worldwide, contributing to the global burden of stroke, particularly in the Asian population. However, there is no non-invasive, easy to popularize and economic for intracranial artery stenosis in mass population screening. This study aims to evaluate the predictive value of retinal vascular signs for intracranial artery stenosis (ICAS) and explore a new screening method.

Detailed Description
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Intracranial atherosclerosis stenosis (ICAS) is a leading cause of ischemic stroke worldwide, contributing to the global burden of stroke, particularly in the Asian population. Compared with the other stroke subtypes, patients with ICAS particularly the degree of stenosis≥50% had more severe stroke, stayed longer in the hospital and higher risk of recurrent ischemic events. However, there is no non-invasive, easy to popularize and economic for intracranial artery stenosis in mass population screening. Retinal imaging has great advantages including share the same embryological origin, anatomic features, and physiological properties with brain, non-invasive, easy to popularize, inexpensive and possess good economic benefits. Therefore, investigators design this study to assess the predictive value of retinal vascular signs for intracranial artery stenosis (ICAS) and hope to explore a new screening method.

Official Title
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The Predictive Value of Retinal Vascular Signs for Patients With Intracranial Artery Stenosis: A Prospective, Continuity Study, Cross-sectional Study

Conditions
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Intracranial Stenosis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age≥35 Accept TCD examination and fundus examination Signed informed consent Exclusion Criteria: Non-atherosclerotic stenosis, such as arteritis, moyamoya disease, arterial dissection, vascular malformation, etc., which were clearly diagnosed. Intracranial space-occupying lesions Jugular vein and intracranial venous lesions Patients with severe cardiac, hepatic, renal disease. Life expectancy of less than 1 year due to co-morbid conditions. Known pregnancy (or positive pregnancy test), or breast-feeding. Pathological myopia fundus changes Glaucoma Refractive medium turbidity affects fundus observation Anterior macular membrane of both eyes Papilledema, optic neuritis and optic neuropathy Patients who have had internal eye surgery in the last six months (including fundus laser) Previous history of internal eye trauma Poor image quality of fundus and images Any condition which, in the judgment of the investigator, might increase the risk to the patient.

Ages Eligible for Study
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Minimum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity | Number of true positives /(number of true positives + number of false negatives)*100 | 6 months | 
| Specificity | Number of true negatives /(number of true negatives + number of false positives)*100 | 6 months | 
| Positive predictive value | Positive predictive value = true positive cases /(true positive cases + false positive cases)*100 | 6 months | 
| Negative predictive value | Negative predictive value = number of true negatives /(number of true negatives + number of false negatives)*100 | 6 months |