The purpose of this study is to assess the effectiveness and safety of the Flow Diverter (Tonbridge) by collecting data from subjects who receive endovascular treatment of intracranial aneurysms.

This is a prospective, multi-center, single-arm clinical trial carried out in 7 research centers over China. In this study, enrolled patients are treated with the Flow Diverter (Tonbridge) for intracranial aneurysms. The objective of this study is to evaluate the effectiveness and safety of the Flow Diverter (Tonbridge) for treatment of intracranial aneurysms.

Inclusion Criteria:

• Age 18 to 80 years, any gender;
• A single unruptured intracranial aneurysm locates in the intracranial segment of internal carotid artery (ICA) or vertebral artery (VA), which diagnosed by DSA;
• The maximal diameter of the target aneurysm < 10 mm diagnosed by DSA;
• The target aneurysm with a neck ≥ 4 mm or a dome to neck ratio < 2 diagnosed by DSA;
• The target aneurysm with a parent vessel diameter of 2.0-6.5 mm;
• Subject or guardian is able to understand the purpose of study, shows sufficient compliance with the study protocol and provides a signed informed consent form.

Exclusion Criteria:

• Diagnosed as with cerebrovascular malformations;
• Intracranial hemorrhage within 30 days pre-procedure;
• Modified Rankin Scale (mRS) score ≥ 3 in pre-procedure;
• Platelet (PLT) < 60×10^9/L or known platelet dysfunction or International Normalized Ratio (INR) > 1.5;
• Heart, lung, liver and renal failure or other severe diseases (such as intracranial tumor, systemic infection, disseminated intravascular coagulation, myocardial infarction within 12 months before enrollment, history of severe psychosis, severe stenosis or occlusion of cerebral feeding artery);
• Subject who is not appropriate for flow diverter delivery and deployment judged by investigators (severe stenosis of parent artery, severe tortuosity of parent artery, stent failing to reach the lesion, stent in the target lesion of parent artery, etc.);
• Major surgery within 30 days before enrollment, or intending to receive surgery within 180 days after enrollment;
• Allergic history of anesthetics and contrast agents, or contraindication for dual antiplatelet or/and anticoagulant therapy;
• Allergic history of metals such as nickel-titanium alloy;
• Life expectancy < 12 months;
• Pregnant or breastfeeding women;
• Subject has participated in other drug or medical device clinical trials within 1 month before signing informed consent;
• Other conditions judged by the investigators as unsuitable for enrollment.