Basics and Principles in the Application of Onyx LD Liquid Embolic System in the Endovascular Treatment of Cerebral Arteriovenous Malformations

Abstract

solution consisting of the embolic component and the tantalum powder.The microcatheter is flushed with saline and subsequently after the dead space volume is filled with 0.23 to 0.26 ml of pure DMSO depending on witch catheter is deployed (Ultraflow TM or Marathon TM , Micro Therapeutics, Inc., Irvine, CA).It is important to follow these steps very carefully in order to avoid unintentional precipitation of Onyx, which immediately begins when there is contact to water, saline solution or blood.Therefore, the catheter hub requires to be flushed with DMSO also.After the air-bubble-free aspiration of the Onyx in a dedicated syringe, the syringe is connected to the microcatheter producing a clear interface between Onyx and DMSO by positioning the syringe vertically immediately after the connection or, more simply, by using a special Interface-Adapter. Application of Onyx LD in central AVMsThe most important factor for successful embolization of cerebral or spinal AVMs is the intranidal positioning of the microcatheter (figure 1).Beside clinical experiences experimental data using a hydraulic pump model or the rete mirabile 14 of the swine also clearly demonstrat-