Endovascular coil embolization is a percutaneous approach to treat an intracranial aneurysm from within the blood vessel without the need of a craniotomy. In this procedure, a microcatheter is inserted into the femoral artery near the groin and navigated to the site of the aneurysm. Small helical platinum coils are deployed through the microcatheter to fill the aneurysm, and prevent it from further expansion and rupture. Health Canada has approved numerous types of coils and coil delivery systems to treat intracranial aneurysms. The most favoured are controlled detachable coils. Coil embolization may be used with other adjunct endovascular devices such as stents and balloons.
The advantage of an endovascular approach is that the coils promote the formation of thrombi in the aneurysm.
However, coil embolization is associated with a higher risk of recurrence than clip ligation.
With the increasing number of aneurysm recurrences after failed coiling procedures, the best retreatment strategy remains unknown.
Intraprocedural rupture and thrombus formation are serious complications during coiling of ruptured intracranial aneurysms, and they more often occur in patients with anterior communicating artery aneurysms.
Parent artery occlusion
A retrospective study in 322 consecutive patients with ruptured cerebral aneurysms who were treated with coil embolization over an 8-year period from January 2005 to December 2012, were classified by morphology according to multilobulation, presence of a daughter sac, and presence of a small basal outpouching (SBO).
The incidence of IPR was 4.8% (16 of 332). In terms of aneurysm configuration, the presence of multilobulation (100.0% [16 of 16] in the IPR group vs 89.2% [282 of 316] in the non-IPR group, p = 0.388) and daughter sac (75.0% [12 of 16] in the IPR group vs 59.2% [187 of 316] in the non-IPR group, p = 0.208) were not significantly associated with IPR. However, SBO, found in 9% (30 of 332) of the study population, was significantly associated with IPR (56.3% [9 of 16] in the IPR group vs 6.7% [21 of 316] in the non-IPR group, OR 18.06, p < 0.0001).
The more general groups of multilobulation and daughter sac were not significantly associated with IPR, although the more specific subgroup with an SBO was. More confirmation studies on these results are required, but they point to the possibility that SBO (with its possible connection to basal rupture) is an important morphological risk factor for IPR during coiling. In addition, future comparison of coiling and clipping treatment for ruptured aneurysms associated with an SBO seems necessary 1).