Overview
Histoacryl (B. Braun) is an N-butyl-2-cyanoacrylate (NBCA) liquid embolic agent used for permanent vascular occlusion. On contact with ionic solutions (such as blood), it undergoes rapid exothermic polymerisation to form a solid cast within the vessel lumen. It is the standard glue embolic agent in UK interventional radiology practice.
Indications
Acute gastrointestinal haemorrhage (particularly gastric variceal bleeding)
Arteriovenous malformations (AVMs)
Type II endoleak embolisation
Varicocoele embolisation (in combination with coils)
Portal vein embolisation
Acute traumatic haemorrhage where rapid occlusion is needed
Key Features
Instantaneous polymerisation — provides immediate vessel occlusion on blood contact
Permanent occlusion — the polymerised cast is non-resorbable
Penetrates distally — liquid nature allows it to reach small distal vessels that coils and particles cannot access
Radiolucent — must be mixed with Lipiodol for fluoroscopic visibility
Preparation
Histoacryl must be mixed with Lipiodol (ethiodised oil) to:
Provide radiopacity for fluoroscopic visualisation
Slow the polymerisation rate, allowing controlled injection
| Ratio (Histoacryl : Lipiodol) | Polymerisation Speed | Use Case |
|---|---|---|
| 1:1 | Fast (~1 second) | High-flow AVMs, large varices |
| 1:2 | Moderate (~2–3 seconds) | Standard embolisation |
| 1:3 to 1:5 | Slow (~5–7 seconds) | Distal penetration, small vessels |
Technique Tips
Flush the catheter with 5% dextrose (D5W) before and between injections — dextrose is non-ionic and will not trigger polymerisation. Never use saline.
Use a dedicated microcatheter that you are prepared to sacrifice — glue can bond the catheter to the vessel wall.
Inject in a single, continuous, brisk push. Hesitation mid-injection risks gluing the catheter tip in situ.
Withdraw the catheter immediately after injection — do not aspirate.
Practice the injection technique on the bench before use. The "push and pull" must be a single confident action.
Have a bowl of D5W on the table to soak equipment. Any residual glue on instruments will set on contact with blood or saline.
Subtraction fluoroscopy or roadmap is essential to see the glue cast against the Lipiodol-opacified target.
Safety Considerations
Non-target embolisation — the liquid can travel through anastomoses or reflux into non-target vessels. Precise catheter positioning is critical.
Catheter retention — if the catheter is not withdrawn promptly, it may become permanently bonded in the vessel.
Exothermic reaction — polymerisation generates heat. Avoid large volumes in enclosed spaces near sensitive structures.