Onyx cast thrombectomy: bailout during thalamic AVM embolization.

Area of Science:

• Neurology
• Neurosurgery
• Interventional Radiology

Background:

• Cerebral arteriovenous malformations (AVMs) are treated with microsurgical resection, radiosurgery, or endovascular embolization.
• Endovascular embolization, while effective, carries risks including hemorrhage and ischemic events from embolic migration or vessel occlusion.

Purpose of the Study:

• To present a case of Onyx embolization for a ruptured thalamic AVM.
• To demonstrate a novel bailout technique for managing Onyx reflux into the parent artery.

Main Methods:

• Endovascular embolization of a ruptured thalamic AVM using Onyx.
• Management of Onyx reflux into the posterior cerebral artery using a combined stent-retriever and aspiration catheter technique.

Main Results:

• Onyx reflux into the posterior cerebral artery occurred, causing complete vascular occlusion.
• The bailout technique successfully dislodged and retrieved the Onyx cast.
• Total occlusion of the targeted AVM feeder was maintained.

Conclusions:

• Endovascular treatment of AVMs can be complicated by embolic material migration.
• A combined stent-retriever and aspiration technique is an effective bailout strategy for managing Onyx reflux.
• This technique can prevent ischemic complications during AVM embolization.