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

Traditional Group (Stent Assisted Coiling):

The patient is placed in a supine position. After satisfactory general anesthesia, the right groin area is routinely disinfected and draped. The right femoral artery sheath is replaced with an 8F sheath. Systemic heparinization is administered, followed by continuous pressurized infusion. A 6F long sheath plus a 5F multifunction catheter are advanced with a Terumo guidewire, and the long sheath is positioned in the left vertebral artery. A micro guidewire is used with a microcatheter to selectively catheterize the left posterior cerebral artery P2 segment, and then the microcatheter is advanced into the aneurysm. Through the microcatheter, one coil is semi deployed to form a framing coil, then one stent is deployed through the stent catheter to cover the aneurysm neck. After the first framing coil is detached, several additional coils are sequentially deployed to embolize the aneurysm. Follow up angiography shows no opacification of the a

Flow Diverter Group:

The patient is placed in a supine position. The right groin area is routinely disinfected and draped. Local infiltration anesthesia is applied at the puncture site, and the right femoral artery is punctured using the Seldinger technique. An 8F sheath is inserted, systemic heparinization is administered, and continuous pressurized infusion is started. A 6F long sheath is advanced to the origin of the right internal carotid artery with the assistance of a Terumo guidewire and a multifunction catheter. A 5F intermediate catheter is advanced inside the long sheath to the petrous segment of the right internal carotid artery. 3D cerebral angiography is performed, and after a suitable working angle is obtained, a stent catheter is advanced to the right middle cerebral artery M3 segment with micro guidewire assistance. Manual injection shows no hemorrhage, confirming the true lumen. After calibration and measurement, one flow diverter stent is deployed to cover the ane

Any stroke, all-cause death events within 1 year post-surgery.

Definitions:

1. Stroke defined as: acute focal or global neurological dysfunction due to vascular injury of brain, spinal cord or retina caused by hemorrhage or infarction, symptom duration ≥24 hours, including symptomatic branch stenosis/occlusion due to branch coverage;
2. TIA: transient focal neurological dysfunction due to brain, spinal cord or retinal ischemia, symptom duration <24 hours, without acute infarction;

Imaging cure rate （Raymond-Roy grade I) at 1, 2, and 5 years post-surgery.

Definitions:

Raymond-Roy grade: Class I: complete occlusion, no contrast filling in sac or neck; Class II: neck remnant, sac obliterated, contrast in neck; Class III: aneurysm remnant, contrast in sac.