Using Onyx in endovascular embolization of internal carotid artery large or giant aneurysms

Internal carotid artery (ICA) large or giant saccular aneurysms is challenging for endovascular coil embolization and surgical clipping with a high recanalization and rebleeding rate. We report our results using Onyx in the endovascular treatment of ICA large or giant saccular aneurysms.

During 2008-2010, 5 patients with 5 large or giant saccular aneurysms in ICA were treated with a liquid embolic agent (Onyx; Micro Therapeutics, Irvine, CA). One aneurysm was small (<10mm), 2 were large (≥10mm, <25mm) and 2 were giant saccular aneurysms (≥25mm). Of 3 female and 2 male patients, 3 were incidental and 2 had bleeding. Selective embolization was performed with Onyx alone or a combination with coils. Clinical and anatomic outcomes were assessed with the Modified Glasgow Outcome Scale and follow-up angiography was performed at 4-21 months (mean 12.2 months).

Complete aneurysm occlusion was obtained in all of the aneurysms on immediate control angiogram. There was not any procedure-related complication. No recanalization was observed at the follow- up periods. There were 2 ICA occlusions in giant ICA aneurysms. The 5 patients were all clinically asymptomatic at follow-up.

Endovascular embolization with Onyx is a useful treatment for ICA large or giant aneurysms, which is unsuitable for coiling or surgical treatment.