This minimally invasive procedure is performed under general anesthesia and is similar to a cardiac catheterization.
As reviewed in the cerebral angiography section above, a small plastic tube (catheter) is placed into an artery of the leg and advanced under x-ray guidance into the artery that supplies blood to the aneurysm. A smaller tube called a microcatheter is then advanced under x-ray guidance into the aneurysm. Special metallic platinum coils are carefully advanced into the aneurysm until it is completely filled. The coils within the aneurysm cause blood to stop flowing within the aneurysm. This prevents leakage of blood and supports permanent healing of the aneurysm. In some circumstances, the anatomy of the aneurysm is such that coils cannot be seated securely without blocking the blood flow of the parent artery (Figure 1). In these circumstances specially designed metallic stents (Figure 2) or a balloon are placed across the orifice (neck) of the aneurysm to aid in coil placement.
Case 1: Aneurysm Coiling
A: An AP view of an aneurysm of the right internal carotid artery. B: Magnified AP view demonstrating a un-ruptured right internal carotid artery aneurysm (arrow). C: Intra-procedural view of the aneurysm during endovascular coiling while the platinum coils are being deployed within the aneurysm. Note that the aneurysm sac fills with contrast suggesting incomplete embolization. The guide catheter and microcatheter are visible within the normal carotid artery and are used to deliver the coils to the aneurysm. D: Complete embolization (blue arrow).
Case 2: Stent-Assisted Coiling
A:AP angiogram of a unruptured aneurysm of the basilar artery. These aneurysms are difficult to access surgically, thus endovascular coiling is often the preferred method treatment. The aneurysm is “wide-necked” and will not safely hold coils without the assistance of a stent to maintain patency of the normal parent vessel.
B: Intra-procedural view after a specially designed stent (not visible) has been placed to protect the normal blood vessels. Endovascular coils are being deployed within the aneurysm and are held within the aneurysm by the stent. The physical nature of the coils is apparent on this image.
C: Final view of the aneurysm after it has been successfully treated with platinum coils. The aneurysm no longer fills with contrast or blood. The normal blood vessels have excellent blood flow and the stent is effectively holding the coils in placed within the aneurysm.
Fusiform aneurysm treated with flow diverting stent: