Repositioning of displaced guglielmi detachable coils after endosaccular embolisation using a modification of the neck plastic technique. A technical note.

After undergoing prior partial surgical clipping of an acutely ruptured internal carotid aneurysm, a 29-year-old woman was referred for endovascular treatment of the gradually enlarging aneurysm remnant. The aneurysm had a somewhat peculiar ellipsoid configuration due to placement of the clip, with the largest dimension measuring less than 4 mm, and the neck measuring approximately 2 mm. Using the conventional endosaccular coil embolisation technique, two small electrolytically detachable coils were carefully folded into the aneurysm sac to produce excellent tight packing. However, immediately after detachment,a loop of the second coil inadvertently herniated out of the aneurysm into the center of the parent artery, exhibiting substantial pulse synchronous displacement. This created a potentially unstable situation for the remaining coils within the embolised aneurysm. To correct this problem we attempted to reposition the loop into the aneurysm using a modification of the previously described neck plastic technique. This technique succeeded without untoward complication. Although there are theoretical risks and limitations, the modified neck plastic technique may be useful in selective cases of inadvertent coil misplacement during endosaccular coil embolisation of aneurysms with the GDC system.