Onyx prevents the bleeding of ruptured aneurysms during interventional embolization.

Endovascular treatment has been acknowledged as an effective treatment for intracranial aneurysms, showcasing favorable clinical outcomes and providing robust protection against rebleeding and rupture. Notably, during the endovascular procedure, significant complications include intraprocedural aneurysmal rupture (IAR) induced by microcatheters, microguidewires, or spring coils, along with thromboembolic events, significantly escalating patient mortality and disability. Current approaches against for IARs involve various strategies such as heparin reversal, compression of the common carotid artery or upstream soft guidewire to mitigate blood flow, management of intracranial pressure and blood pressure, and balloon-assisted or unassisted rapid dense embolization of the aneurysm. Nevertheless, these measures may prove insufficient in halting hemorrhage, especially in scenarios where additional coils cannot be added for dense embolization due to inherent limitations. In this context, we introduce a novel strategy for the prompt, safe, and effective cessation of aneurysm bleeding, which involves injecting an appropriate quantity of Onyx into the aneurysm through a microcatheter while safeguarded by an aneurysm-carrying arterial braided stent. Initially, we attempted dense embolization by filling multiple coils. However, in cases where continued coil filling proved unfeasible or failed to sufficiently prevent contrast agent extravasation, we opted for Onyx injection into the aneurysm. Utilizing Onyx effectively prevented further blood extravasation without adversely impacting the aneurysm-carrying artery or distal vessels, leading to favorable prognoses for all patients. This article delineates our embolization strategy, highlighting the efficacy and safety of Onyx injection as an alternative or complementary measure in managing complications arising from endovascular coil embolization.