Introduction Intentional partial coiling dome protection of ruptured cerebral aneurysms was recently reported to prevent acute rebleeding in SAH patients. There are potential disadvantages to this technique including difficulty keeping coil loops away from the neck of the aneurysm that may impede future clipping attempts or the potential for inadequate coil protection. Emergent off-label, IRB approved utilisation of Onyx HD500 could resolve these issues by providing 100% volume filling of the embolised portion of the aneurysm with greater control to prevent embolic material encroachment at the neck of the aneurysm.
Methods Three patients whom had intentional emergent partial embolisation of a ruptured aneurysm using Onyx HD-500 with a dome protection strategy are reported. In each case, an EV3 4mm x 7mm Hyperform balloon catheter was positioned to protect parent and branch vessels. Each aneurysm was selectively catheterised with an Echelon-10 DMSO compatible microcatheter. After the balloon was inflated to decrease flow currents within the aneurysm, Onyx HD500 was infused slowly as per standard technique until it conformed to the distal aneurysm dome. Cycles of balloon deflation and inflation during embolisation were utilised to prevent ischaemia. Onyx deposition in the proximal 1/3 of the aneurysm near the neck was avoided to allow room for definitive treatment such as placement of a surgical clip.
Results All three patients had successful dome protection with Onyx HD500, leaving room at the neck of the aneurysm for definitive treatment. There were no procedural thromboembolic complications. Two of the patients had good or fair clinical outcomes and delayed surgical clipping was performed with success. There were no issues with the Onyx material preventing clipping or increasing the difficulty of clipping. The third patient was a WFNS SAH grade 5 who was later changed to comfort measures and expired prior to definitive treatment. figure A. Complex ruptured right MCA aneurysm with daughter sac. figure B. Long arrow: dome protection with Onyx cast within daughter sac. Short arrow: surgical clipping at the neck.
Conclusion Dome protection with Onyx HD500 of ruptured complex bifurcation aneurysms with intent for delayed surgical clipping or stent-assisted coiling is a feasible strategy to prevent acute rebleeding when the aneurysm is unfavourable for initial definitive treatment.
Disclosures R. James: 1; C; Brain Aneurysm Foundation, Microvention, Inc., East Carolina University, East-West Collaboration Grant. 4; C; Remedy Pharmaceuticals, Inc. E. Lukosius: None. K. Wainwright: None. H. Kanaan: None.