Embolization with N-Butyl Cyanoacrylate: Properties, Techniques, Applications, and Pitfalls

N-butyl cyanoacrylate (NBCA) glue embolization is a minimally invasive technique widely used in interventional radiology to achieve vascular occlusion. It is a liquid embolic agent that rapidly polymerizes on contact with ionic substances such as blood or saline, allowing immediate solidification and formation of a durable embolus. This property makes it especially effective in controlling arterial bleeding from small-caliber or tortuous vessels that cannot be accessed by using microcatheters or in cases requiring urgent hemostasis due to severe hemorrhage. The embolization process involves mixing NBCA glue with an oil-based contrast agent to adjust the viscosity and regulate the polymerization rate. Under fluoroscopic guidance, the mixture is injected through a microcatheter by using pressure- or flow-dependent techniques. Modified approaches have also been developed and include flow-controlled injection with use of a balloon catheter or the addition of ethanol to reduce adhesiveness. Clinical applications include embolization for gastrointestinal bleeding and arteriovenous, portal vein, and lymphatic anomalies; preoperative devascularization of hypervascular tumors; and balloon-occluded retrograde transvenous obliteration. Despite the effectiveness of NBCA glue embolization, the risk of nontarget embolization remains a significant concern, potentially resulting in tissue necrosis or ischemia. Therefore, a comprehensive understanding of the vascular anatomy and hemodynamics is essential to minimize complications. NBCA glue embolization is a powerful and versatile tool for vascular occlusion. Successful outcomes rely on meticulous patient selection, adherence to procedural protocols, and the experience of the operator. ^©RSNA, 2026 Supplemental material is available for this article.