Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

FLOW-diverted Glue Embolization to Target lesions (FLOW-GET) technique for spinal vascular diseases: A technical note

We present and exemplify the flow-diverted glue embolization to target lesions (FLOW-GET) technique for spinal vascular diseases. In this technique, the occlusion of the posterior intercostal artery or dorsal muscular branch by coils diverts the injected glue from the segmental artery to the target lesions. This technique was applied to a ruptured retrocorporeal artery aneurysm and spinal dural arteriovenous fistulas. The FLOW-GET accomplished the complete obliteration of all lesions. This simple and useful technique can be applied to spinal vascular lesions even if a microcatheter is not placed in proper feeders or advanced close to the shunt points or aneurysms.

A multi-step approach to the treatment of giant scalp congenital hemangiomas: a report of two cases

This is a review of two cases of neonatal giant scalp congenital hemangioma. Both patients were treated with propranolol using a similar multi-step approach that included transarterial embolization of the supplying arteries followed by surgical resection of the lesion. In this report, we discuss the treatments, complications, and clinical outcomes of interventions and surgical procedures.

X-ray Microtomography to Assess Determinants of In Vivo N-Butyl Cyanoacrylate Glubran®2 Polymerization: A Rabbit-Model Study

Although introduced decades ago, few cyanoacrylate glues have been approved for endovascular use, despite evidence of their usefulness, notably for complex procedures suchas hemostatic embolization. Indications include massive bleeding requiring emergent hemostasis and prevention of severe bleeding during scheduled surgery to remove a hypervascular tumor. Adding radiopaque Lipiodol Ultra Fluid® (LUF) modulates glue polymerization and allows fluoroscopic guidance, but few comparative in vivo studies have assessed the impact of the resulting change in glue concentration or of other factors such as target-vessel blood flow. In a rabbit model, we used ex vivo X-ray microtomography to assess the results of in vivo renal-artery embolization by various mixtures of N-butyl cyanoacrylate (NBCA), metacryloxysulfolane, and LUF. Overall, penetration to the superficial interlobular arteries was achieved in about two-thirds of cases and into the capillaries in nearly half the cases, while cast fragmentation was seen in slightly more than half the cases. Greater NBCA dilution and the blocked-blood-flow technique were independently associated with greater distality of penetration. Blocked-blood-flow injection was independently associated with absence of fragmentation, capillary penetration, a shorter cast-to-capsule distance, and higher cast attenuation. A larger mixture volume was independently associated with higher indexed cast ratio and deeper penetration. Finally, microtomography is an adapted tool to assess ex vivo distribution of glue cast.

Initial clinical experience with N-hexyl cyanoacrylate for neuroendovascular embolization

OBJECTIVE

To report our initial clinical experience with N-hexyl cyanoacrylate (NHCA), a novel liquid agent for neurovascular embolization.

METHODS

Four paragangliomas were treated with percutaneous embolization using NHCA as the sole embolic material. In one dural arteriovenous fistula (dAVF), NHCA was used in combination with other embolic materials. Procedural specifics, complications and angiographic results were retrospectively evaluated.

RESULTS

Total or subtotal devascularization was obtained in 3 of the 4 paragangliomas. In the largest tumor, only partial devascularization could be achieved. The dAVF was completely occluded. Catheter entrapment did not occur. After dAVF treatment, the patient had an asymptomatic lacunar infarction, while there was no procedural morbidity related to paraganglioma treatment.

CONCLUSIONS

In this series, neurovascular embolization with NHCA was feasible and effective. It may be particularly beneficial for small and tortuous vessels that require low-profile catheterization and a slow and controlled polymerization. Further studies are necessary to prove the benefits of NHCA over established embolic agents.

Glue, Onyx, Squid or PHIL? Liquid Embolic Agents for the Embolization of Cerebral Arteriovenous Malformations and Dural Arteriovenous Fistulas

Background

Endovascular embolization is an effective treatment option for cerebral arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs). A variety of liquid embolic agents have been and are currently used for embolization of AVMs and DAVFs. Knowledge of the special properties of the agent which is used is crucial for an effective and safe embolization procedure.

Material and Methods

This article describes the properties and indications of the liquid embolic agents which are currently available: cyanoacrylates (also called glues), and the copolymers Onyx, Squid and PHIL, as well as their respective subtypes.

Results

Cyanoacrylates were the predominantly used agents in the 1980s and 1990s. They are currently still used in specific situations, for example for the occlusion of macro-shunts, for the pressure cooker technique or in cases in which microcatheters are used that are not compatible with dimethyl-sulfoxide. The first broadly used copolymer-based embolic agent Onyx benefits from a large amount of available experience and data, which demonstrated its safety and efficacy in the treatment of cerebral vascular malformations, while its drawbacks include temporary loss of visibility during longer injections and artifacts in cross-sectional imaging. The more recently introduced agents Squid and PHIL aim to overcome these shortcomings and to improve the success rate of endovascular embolization. Novelties of these newer agents with potential advantages include extra-low viscosity versions, more stable visibility, and a lower degree of imaging artifacts.

Conclusion

All the available liquid embolic agents feature specific potential advantages and disadvantages over each other. The choice of the most appropriate embolic agent must be made based on the specific material characteristics of the agent, related to the specific anatomical characteristics of the target pathology.