Regarding “Embolization of Intracranial Dural Arteriovenous Fistulas Using PHIL Liquid Embolic Agent in 26 Patients: A Multicenter Study”

BackgroundLiquid embolic agents are the preferred embolic material in endovascular treatment of pial and brain arteriovenous malformations and dural arteriovenous fistulas (DAVFs). There is little choice available in interventional neuroradiology practice other than two of the most commonly used liquid embolic agents—n-butyl cyanoacrylate and the Onyx liquid embolic system (ev3 Neurovascular, Irvine, California, USA). PHIL (Precipitating Hydrophobic Injectable Liquid) (Microvention, Inc California, USA) is a new liquid embolic agent, CE marked and available for clinical use in Europe.ObjectiveTo present our preliminary experience using PHIL in treating cranial and spinal DAVFs.MethodsBetween September 2014 and January 2015, eight patients, with five cranial DAVFs and three spinal DAVFs were treated with PHIL as the sole embolic agent used with intent to cure. Clinical presentation, location of DAVF, Borden type, fluoroscopic time, radiation dose, procedural time, injecting microcatheter used, volume of PHIL injected, complications, immediate angiographic data, premorbid and discharge modified Rankin Scale score, and any neurologic deficits were included in the analysis.ResultsSeven patients were successfully treated with complete angiographic exclusion of the fistula in a single sitting. Treatment failed in one patient where only suboptimal microcatheter positioning could be achieved and PHIL failed to penetrate the fistula's nidus. Venous penetration was achieved in all other patients except one with a small fistula, but with adequate fistula penetration by the embolic material. No other technical complication or neurologic deterioration occurred in any of the patients.ConclusionsPHIL liquid embolic agent appears to be an excellent alternative embolic material with certain advantages compared with other available liquid embolic agents. Further studies are required to fully evaluate its safety and efficacy.

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Endovascular treatment of congenital brain arteriovenous fistulas with combination of detachable coils and onyx liquid embolic agent

Neuroradiology ◽

10.1007/s00234-010-0681-x ◽

2010 ◽

Vol 52 (12) ◽

pp. 1121-1126 ◽

Cited By ~ 3

Author(s):

Xuefeng Wang ◽

Qihong Wang ◽

Gong Chen ◽

Bing Leng ◽

Donglei Song

Keyword(s):

Endovascular Treatment ◽

Embolic Agent ◽

Arteriovenous Fistulas ◽

Liquid Embolic ◽

Liquid Embolic Agent ◽

Detachable Coils

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Coil and Onyx embolization of a torcular herophili dural arteriovenous fistula in a full-term neonate with advanced heart failure using a transumbilical approach

Journal of Neurosurgery Pediatrics ◽

10.3171/2018.6.peds1819 ◽

2019 ◽

Vol 23 (1) ◽

pp. 80-85

Author(s):

George W. Koutsouras ◽

Redi Rahmani ◽

Tyler Schmidt ◽

Howard Silberstein ◽

Tarun Bhalla

Keyword(s):

Heart Failure ◽

Severe Congestive Heart Failure ◽

Full Term ◽

Embolic Agent ◽

Secondary Complications ◽

Normal Birth ◽

Arteriovenous Fistulas ◽

Liquid Embolic ◽

Life Threatening ◽

Liquid Embolic Agent

Neonatal dural arteriovenous fistulas (DAVFs) are rare, but if left untreated will advance to life-threatening neurological and cardiovascular compromise. Endovascular treatment is the preferred treatment modality for DAVFs. The goal of endovascular therapy is to obliterate feeding vasculature and prevent secondary complications. Endovascular access can be difficult to obtain in a neonate. The authors present the case of a full-term, normal birth weight neonate with severe congestive heart failure secondary to a congenital DAVF of the torcular herophili that was successfully treated with transumbilical arterial coil embolization and a liquid embolic agent.

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Onyx embolization for dural arteriovenous fistulas: a multi-institutional study

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2020-017109 ◽

2021 ◽

pp. neurintsurg-2020-017109

Author(s):

Yangchun Li ◽

Stephanie H Chen ◽

Ridhima Guniganti ◽

Akash P Kansagra ◽

Jay F Piccirillo ◽

...

Keyword(s):

Multicenter Study ◽

Functional Outcomes ◽

Functional Independence ◽

Sigmoid Sinus ◽

Embolic Agent ◽

Occipital Artery ◽

Arteriovenous Fistulas ◽

Dural Arteriovenous Fistulas ◽

Complete Obliteration

BackgroundAlthough the liquid embolic agent, Onyx, is often the preferred embolic treatment for cerebral dural arteriovenous fistulas (DAVFs), there have only been a limited number of single-center studies to evaluate its performance.ObjectiveTo carry out a multicenter study to determine the predictors of complications, obliteration, and functional outcomes associated with primary Onyx embolization of DAVFs.MethodsFrom the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database, we identified patients who were treated for DAVF with Onyx-only embolization as the primary treatment between 2000 and 2013. Obliteration rate after initial embolization was determined based on the final angiographic run. Factors predictive of complete obliteration, complications, and functional independence were evaluated with multivariate logistic regression models.ResultsA total 146 patients with DAVFs were primarily embolized with Onyx. Mean follow-up was 29 months (range 0–129 months). Complete obliteration was achieved in 80 (55%) patients after initial embolization. Major cerebral complications occurred in six patients (4.1%). At last follow-up, 84% patients were functionally independent. Presence of flow symptoms, age over 65, presence of an occipital artery feeder, and preprocedural home anticoagulation use were predictive of non-obliteration. The transverse-sigmoid sinus junction location was associated with fewer complications, whereas the tentorial location was predictive of poor functional outcomes.ConclusionsIn this multicenter study, we report satisfactory performance of Onyx as a primary DAVF embolic agent. The tentorium remains a more challenging location for DAVF embolization, whereas DAVFs located at the transverse-sigmoid sinus junction are associated with fewer complications.

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

Clinical Neuroradiology ◽

10.1007/s00062-021-01066-6 ◽

2021 ◽

Author(s):

Dominik F. Vollherbst ◽

René Chapot ◽

Martin Bendszus ◽

Markus A. Möhlenbruch

Keyword(s):

Arteriovenous Malformations ◽

Vascular Malformations ◽

Endovascular Embolization ◽

Embolic Agent ◽

Cerebral Arteriovenous Malformations ◽

Arteriovenous Fistulas ◽

Advantages And Disadvantages ◽

Embolic Agents ◽

Liquid Embolic ◽

Dural Arteriovenous Fistulas

Abstract 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.

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Precipitating hydrophobic injectable liquid embolization of intracranial vascular shunts: initial experience and technical note

Journal of Neurosurgery ◽

10.3171/2017.6.jns16447 ◽

2018 ◽

Vol 129 (5) ◽

pp. 1217-1222 ◽

Cited By ~ 5

Author(s):

Shriram Varadharajan ◽

Arvinda Hanumanthapura Ramalingaiah ◽

Jitender Saini ◽

Arun Kumar Gupta ◽

B. Indira Devi ◽

...

Keyword(s):

Endovascular Embolization ◽

Technical Note ◽

Embolic Agent ◽

Arteriovenous Fistulas ◽

Embolic Agents ◽

Liquid Embolic ◽

Complete Obliteration ◽

Liquid Embolic Agent ◽

Pial Arteriovenous Fistula

Precipitating hydrophobic injectable liquid (PHIL) is a newly available liquid embolic agent for endovascular therapy. It is nonadhesive and composed of a biocompatible polymer dissolved in dimethyl sulfoxide solvent and bonded covalently with iodine.In this report, the authors present their preliminary experience using PHIL in the treatment of intracranial vascular shunts. Between July 2015 and December 2015, 11 patients underwent endovascular embolization using the PHIL embolic agent. Five patients had arteriovenous malformations, 4 had dural arteriovenous fistulas, 1 patient had a carotid-cavernous fistula, and 1 patient had a pial arteriovenous fistula. Clinical features, angioarchitectural characteristics, procedural details, and periprocedural complications were included in the analysis.Complete or near-complete obliteration of the nidus or fistulas was achieved in 8 of these patients. Partial embolization (approximately 80% in 2 and 30% in 1) was attained in the other 3 patients. Satisfactory venous penetration after nidal embolization was achieved in all patients. In 1 patient, the microcatheter could not be retrieved. No other major complications related to PHIL injection were noted during the procedure or periprocedural period. Clinical follow-up ranging from 8 months to 1 year showed good outcomes in all but 1 patient, who experienced an intraventricular hemorrhage 6 weeks after embolization.PHIL appears to be an effective alternative embolic material with certain advantages over other available liquid embolic agents. Further studies with adequate follow-up are required to fully evaluate its safety and efficacy.

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