LIBRO is INVAMED's EVOH liquid embolic system, a non-adhesive liquid embolic agent formulated from ethylene vinyl alcohol copolymer, dimethyl sulfoxide (DMSO) carrier solvent, and micronized tantalum powder for fluoroscopic visibility. It is intended for embolization of arteriovenous malformations (AVMs) and hypervascular tumors by trained interventional physicians. This overview summarizes the composition, delivery considerations, and intended use of the LIBRO system.
What Is the Composition of LIBRO EVOH?
LIBRO is supplied in two concentrations designed to accommodate different flow and penetration requirements:
- LIBRO 6%: a lower-viscosity formulation intended for scenarios where a physician anticipates the need for greater distal penetration into a vascular network.
- LIBRO 8%: a higher-viscosity formulation that may be selected when a physician wants more controlled, localized precipitation.
Both concentrations incorporate suspended tantalum powder, which provides radiopacity so the embolic column can be tracked under fluoroscopic imaging throughout the injection.
How Does the Precipitation Mechanism Work?
LIBRO relies on a solvent-exchange mechanism. The EVOH copolymer is dissolved in DMSO for storage and injection. Once the mixture contacts blood or aqueous tissue fluid, the DMSO diffuses outward and the EVOH copolymer precipitates in place, forming a coherent, spongy cast that conforms to the vessel lumen.
Because this is a non-adhesive mechanism—as opposed to cyanoacrylate-based adhesive embolics that polymerize on contact—physicians are generally able to perform the injection in a more controlled, staged fashion, pausing between injections if imaging confirms adequate technique.
What Are the Delivery Considerations?
LIBRO is designed for delivery through compatible microcatheters, such as INVAMED's MicroCATH neurovascular catheter family, which is intended for delivery of embolic materials including liquid agents and coils in neurovascular and peripheral interventions.
Because DMSO can affect certain catheter and hub materials, physicians should confirm microcatheter compatibility and adhere strictly to the Instructions for Use (IFU) regarding injection technique, dead-space priming, and injection rate. Non-target embolization is a recognized risk of any liquid embolic procedure, and careful technique under continuous imaging guidance is essential.
What Is the Intended Clinical Use?
LIBRO EVOH liquid embolic is intended for use in embolization of:
- Brain and peripheral arteriovenous malformations (AVMs)
- Hypervascular tumors, including in pre-surgical devascularization contexts
As with all embolization procedures, patient selection, anatomical suitability, and procedural planning are determined by the treating physician based on diagnostic imaging and clinical judgment. All procedures carry inherent risks, and outcomes vary by patient.
Frequently Asked Questions
What distinguishes LIBRO from adhesive liquid embolics?
LIBRO uses a non-adhesive, solvent-precipitation mechanism, meaning it does not polymerize instantly on contact with blood the way cyanoacrylate-based adhesives do. This is intended to give physicians more control during staged injections, though technique and vessel anatomy both influence procedural approach.
Why does LIBRO contain tantalum?
Tantalum is a radiopaque metal suspended within the EVOH-DMSO mixture so the embolic cast is visible under fluoroscopy. This allows the physician to monitor the extent and distribution of the embolic material during injection.
Is LIBRO compatible with any microcatheter?
Microcatheter compatibility should always be confirmed against the LIBRO Instructions for Use (IFU), since DMSO solvent compatibility varies by catheter material. INVAMED's MicroCATH family is designed for delivery of liquid embolic agents and coils in relevant anatomies.
Related INVAMED Resources
- LIBRO Non-Adhesive Embolization Agent
- MicroCATH Neurovascular Catheter Family
- Embolization Products at INVAMED
Medical Disclaimer: This article is provided for general informational and educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendation. It is not a substitute for consultation with a qualified healthcare professional. Product indications, availability, and regulatory status vary by country. Always refer to the official Instructions for Use (IFU) and consult a licensed physician for guidance specific to your situation. INVAMED devices are intended for use by trained healthcare professionals.