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Redefining Onyx HD 500 in the Flow Diversion Era
Richard Tyler Dalyai1, Ciro Randazzo, George Ghobrial
1Department of Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, PA 19107, USA.
International Journal of Vascular Medicine
|November 29, 2011
Summary
Onyx HD-500, a liquid embolic agent, effectively treated wide-neck intracranial aneurysms in 21 patients. This new embolization method achieved high occlusion rates with minimal recanalization, offering a safe alternative for complex aneurysm treatment.
Area of Science:
- Neurology
- Interventional Neuroradiology
- Biomaterials
Background:
- Wide-neck intracranial aneurysms pose treatment challenges due to high risks of incomplete occlusion and recanalization with standard detachable platinum coils.
- Liquid embolic agents offer a potential alternative for complex aneurysm morphologies.
Purpose of the Study:
- To evaluate the safety and efficacy of Onyx HD-500, a novel liquid embolic agent, in treating wide-neck intracranial aneurysms.
- To assess occlusion rates, recanalization, and clinical outcomes in a US case series.
Main Methods:
- Retrospective analysis of 21 patients treated with Onyx HD-500 for wide-neck intracranial aneurysms.
- Aneurysms were located in the anterior circulation; three presented as acute subarachnoid hemorrhages.
- Follow-up included imaging to assess aneurysm occlusion and recanalization.
Main Results:
- Complete aneurysm occlusion was achieved in 19 of 21 patients (90%) immediately post-procedure.
- One patient with a residual neck achieved total occlusion at six-month follow-up.
- No aneurysm recanalization was detected during a mean follow-up of 8.9 months in 11 patients.
- Transient neurologic deficits occurred in 4 patients postoperatively and 1 in a delayed fashion.
Conclusions:
- Embolization with Onyx liquid embolic agent is a safe and effective endovascular treatment for wide-neck intracranial aneurysms.
- Onyx provides a viable option for recurrent aneurysms or those previously treated unsuccessfully with detachable coils.
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