CRAST is to analyze the expression pattern of circular RNA (circRNA) by bioinformatics analysis in patients with acute ischemic stroke and healthy control. The candidate circRNA will be verified as biomarkers for the detection and prognosis of acute ischemic stroke.

Circular RNAs have been highlighted to be involved in the pathological process of ischemic stroke (IS). The purpose of this protocol will investigate the expression pattern of circular RNA (circRNA) by bioinformatics analysis in patients with acute ischemic stroke and healthy control. The candidate circRNA will be verified as biomarkers for the detection and prognosis of acute ischemic stroke. Distinctive expression patterns of circRNA will be identified by individual quantitative real time polymerase chain reaction (qRT-PCR). A diagnostic or predictive model will be established using logistic regression. The panel of these altered circRNAs may be associated with acute IS and could serve as a novel diagnostic or predictive method.

Inclusion Criteria:

• Aged 18 years or older
• Confirmed acute ischemic stroke by a diffusion-weighted imaging-position lesion on magnetic resonance imaging (MRI) and a new lesion on a brain computed tomography (CT) scan
• Within 72 hours of symptom onset
• Good performance status
• Signed an approved informed consents

Exclusion Criteria:

• a history of hemorrhagic infarction, chronic kidney/liver diseases, peripheral arterial occlusive disease, active malignant disease, and inflammatory or infectious diseases

There will be 100 patients suspected of AIS (such as transient ischemic attack), 300 AIS patients and 100 Healthy controls，whose data will be applied for construction and validation of diagnostic and predictive models of circRNA from the circulating blood.