Abstract TP165: Preventing Ophthalmic Complications By Coiling The Orbital Anastomosis Prior To Middle Meningeal Artery Embolization

Background: Embolization of the Middle Meningeal Artery (MMA) is a minimally invasive procedure used as an alternative or adjunctive treatment of chronic subdural hematoma (cSDH). The benefits of MMA embolization have been attributed to targeting of the pathophysiology of cSDH which currently favors a process of increasing inflammatory response causing immature and leaky neovascularization. The major dural arteries and hazards associated with their embolization have been thoroughly described in past literature. The unintended embolization of orbital arteries leading to blindness is the most significant hazard associated with MMA embolization. Purpose: The purpose of this study is to present 5 cases demonstrating the success of our technique in the treatment of cSDH while preventing the possibility of blindness by coiling the anastomotic vessel between MMA and Ophthalmic Artery (OA) branches prior to particle embolization. Methods: After doing an Internal Carotid Artery (ICA) run and ensuring the origination of the OA from the ICA and observing retinal blush, we routinely infused 10-20μg of Nitroglycerine into the main trunk of MMA through a microcatheter to dilate and better visualize the MMA branches including anastomosis. If the meningeo-ophthalmic collaterals were visualized during the follow-up microcatheter run, we coil embolized the proximal segment of those collaterals through the same microcatheter. We then infused 100-300μm particles through the main branches of the MMA supplying the dura. Results: Of the 39 patients who underwent MMA embolization for cSDH, 5 received MMA/OA collateral variants coil embolization followed by successful particle embolization of all MMA branches supplying the dura without complication. Conclusion: In our cSDH patients, the collaterals from MMA to Ophthalmic or Lacrimal branches were safely coil embolized before complete particle embolization of the MMA dural branches. In a few patients these collaterals became obvious after inducing vasodilatation. None of these patients had major complications. This technique may be safer, more effective and cheaper than wedging, gluing or low pressure infusion. Our literature search did not find a similar technique used in this application.