Preoperative embolization of high-flow peripheral AVMs using plug and push technique with low-density NBCA/Lipiodol

Head and Neck Arteriovenous Malformations: Clinical Manifestations and Endovascular Treatments

Arteriovenous malformations (AVMs) are vascular malformations that present high-flow direct communication between the arteries and veins, not involving the capillary beds. They can be progressive and lead to various manifestations, including abnormal skin or mucosal findings, ischemia, hemorrhage, and high-output heart failure in severe cases. AVMs often involve the head and neck region. Head and neck AVMs can present region-specific clinical manifestations, angioarchitecture, and complications, especially in cosmetic appearance and ingestion, respiratory, and neuronal functions. Therefore, when planning endovascular treatment of head and neck AVMs, physicians should consider not only the treatment strategy but also the preservation of the cosmetic appearance and critical functions. Knowledge of the functional vascular anatomy as well as treatment techniques should facilitate a successful management. This review summarizes AVMs' clinical manifestations, imaging findings, treatment strategy, and complications.

In Vivo Animal Study of a Highly Viscous N-butyl Cyanoacrylate Medical Adhesive for Intravenous Embolization

N-butyl cyanoacrylate (NBCA) is a liquid monomer that undergoes an exothermic polymerization reaction to form a solid upon initiation with hydroxyl anions. Recently, EGpresto, a highly viscous NBCA-based adhesive, has been developed for vascular-occlusion purposes. In this study, we investigated the heat of polymerization of EGpresto and compared the results with those of a low-viscosity NBCA glue. Results show that EGpresto exhibited a lower heat of polymerization (64 ± 7 °C vs. 34 ± 1 °C). This was due to its high viscosity, which resulted in a delayed polymerization time. To investigate the efficacy and safety of EGpresto for intravenous embolization, a 14 d in vivo animal test was conducted using three pigs. Five cc of EGpresto was injected into the epigastric vein of each animal. Complete postoperative vein occlusion was confirmed at 7 and 14 d by ultrasonographic visualization. After the animals were sacrificed, the operated and unoperated veins were exposed, and the injected adhesive was found without migration. During the histology, the injected adhesive was not found in the inner or outer vein walls, and the immune reactions seemed to be the only foreign-body reaction, showing that EGpresto is a non-toxic and safe intravascular embolic agent.