Flow Diverter Versus Conventional Endovascular Treatment for Unruptured Wide-Neck Bifurcation Aneurysms (FD-BWA Trial)

Brief Summary： The goal of this clinical trial is to compare whether the traditional approach (stent-assisted coiling) is associated with a lower complication rate than flow diverter (Pipeline™) treatment for unruptured intracranial wide-neck bifurcation aneurysms. It will also evaluate the long-term imaging outcomes and safety of both treatments. The main questions it aims to answer are: * Does the traditional approach result in a lower rate of any stroke or all-cause death within one year after treatment compared to the flow diverter? * What medical problems do participants experience during and after each treatment? * What are the imaging cure and stability rates at 1, 2, and 5 years after treatment? Researchers will compare the traditional approach (stent-assisted coiling) with the flow diverter (Pipeline™) to determine which treatment has better safety and efficacy outcomes. Participants will: * Be randomly assigned to receive either the flow diverter or traditional stent-assisted coiling * Undergo the assigned endovascular procedure * Return for follow-up visits at 30 days, 6 months, 1 year, 2 years, and 5 years after surgery for clinical assessments and imaging examinations (DSA, MRA, or CTA)

Inclusion Criteria: 1. Age 18-75 years; 2. Diagnosis of unruptured intracranial, bifurcation, saccular, wide-neck aneurysm by DSA/CTA/MRA; 3. Patients who can understand the purpose of the trial, voluntarily participate and sign the informed consent form. Exclusion Criteria: 1. Patients with two or more multiple aneurysms that all require treatment within 1 year; 2. Concomitant cerebrovascular diseases such as arteriovenous malformation, moyamoya disease; 3. Ruptured aneurysms and narrow-neck aneurysms; 4. Patients who have had a stroke (cerebral hemorrhage, cerebral infarction) within the past 1 month; 5. Extremely poor clinical condition, modified Rankin Score ≥3; 6. Patients already scheduled for surgery/interventional procedure within 3 months; 7. Patients deemed unsuitable for interventional treatment by the investigator (e.g., no suitable vascular access, excessively tortuous vessels, difficulty delivering stent); 8. Patients unsuitable for anesthesia or endovascular surgery, such as major diseases of heart, lung, liver, spleen, kidney, brain tumors, severe active infections, disseminated intravascular coagulation, severe mental illness; 9. Patients unable to receive antiplatelet or anticoagulant therapy; 10. Patients who have had or may have severe reactions to contrast media precluding pre-treatment medication; 11. Patients with a definite history of allergy to cobalt-chromium, nickel-titanium alloy materials; 12. Participation in other drug or medical device clinical trials before enrollment without reaching the primary endpoint timeframe; 13. Pregnant or breastfeeding women; 14. Patient's life expectancy less than 12 months; 15. Investigator judges that the patient has poor compliance and cannot complete the study as required.