Assessment of human placenta as an ex-vivo vascular model for testing of liquid embolic agent injections with adjunctive techniques

PurposeThis project sought to test the utility of post-delivery human placenta (HP) as a vascular model for liquid embolic agent (LEA) simulation, along with adjunctive techniques.Materials and methodsTwelve LEA injections were performed under fluoroscopy in HP with two reflux control methods: dual lumen ‘mini’ balloon-catheter (n=9); and injection after proximal nBCA plug formation through a second microcatheter (‘pressure cooker’) (n=3). Measured outcomes included liquid embolic agent (LEA) advancement and reflux. Reflux was categorized into three grades: grade 0=no reflux; grade 1=occlusion of side branches without reflux beyond the balloon or plug; and grade 2=reflux beyond the balloon or plug.ResultsSimulation success was greater when a balloon was used rather than with a nBCA plug (89% vs 33%, P=0.054). In eight successful balloon-assisted injections, the reflux grades were: 50% grade 0; 12.5% grade 1; and 37.5% grade 2. The one successful nBCA plug injection had grade 2 reflux. All grade 2 balloon injections occurred when the balloon was positioned across a vessel bifurcation.ConclusionsHP provides excellent simulation for liquid embolic agents with a dual lumen balloon catheter.

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Evaluation of a novel liquid embolic agent (precipitating hydrophobic injectable liquid (PHIL)) in an animal endovascular embolization model

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2017-013144 ◽

2017 ◽

Vol 10 (3) ◽

pp. 268-274 ◽

Cited By ~ 15

Author(s):

Dominik F Vollherbst ◽

Ruth Otto ◽

Andreas von Deimling ◽

Johannes Pfaff ◽

Christian Ulfert ◽

...

Keyword(s):

Waiting Time ◽

Transarterial Embolization ◽

Endovascular Embolization ◽

Embolic Agent ◽

Rete Mirabile ◽

Embolic Agents ◽

Liquid Embolic ◽

Liquid Embolic Agent ◽

Group Survival

BackgroundThe choice of the embolic agent and the embolization technique can have a significant impact on the success of endovascular embolization.ObjectiveTo evaluate a novel iodinated copolymer-based liquid embolic agent (precipitating hydrophobic injectable liquid (PHIL)) in the porcine rete mirabile (RM), serving as an endovascular embolization model. Onyx, as an established liquid embolic agent, served as comparator.Materials and methodsSixteen embolization procedures were performed using PHIL (n=8) or Onyx (n=8) as liquid embolic agent. Waiting time between injections was set to 30 or 60 s (n=4 per study group). Survival time after intervention was 2 hours or 7 days. Embolization characteristics (eg, procedure times, number of injections and volume of embolic agent) and embolization extent (percentage of embolized RM in post-interventional x-ray) were assessed. Post-interventional CT and histopathological analyses were performed.ResultsEmbolization characteristics and embolization extent were not significantly different for PHIL and Onyx, including subgroups (eg, embolization extent 44% vs 69% (medians); p=0.101). For PHIL, extension of the waiting time from 30 to 60 s led to a significantly higher embolization extent (24% vs 72% (medians); p=0.035). Moderate disintegration and mild inflammation of the embolized blood vessels were present for both embolic agents.ConclusionPHIL is feasible for transarterial embolization in an acute and subacute endovascular embolization model. In this preliminary experimental in vivo study, embolization characteristics, embolization extent, and biocompatibility seem to be similar to those of Onyx.

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Use of Intracranial Stenting to Secure Unstable Liquid Embolic Casts in Wide-Neck Sidewall Intracranial Aneurysms

Operative Neurosurgery ◽

10.1227/01.neu.0000350983.03348.06 ◽

2010 ◽

Vol 66 (suppl_1) ◽

pp. ons-92-ons-98 ◽

Cited By ~ 2

Author(s):

Scott D. Simon ◽

Demetrius K. Lopes ◽

Robert A. Mericle

Keyword(s):

Intracranial Aneurysms ◽

Vascular Reconstruction ◽

The United States ◽

High Viscosity ◽

Preliminary Evidence ◽

Embolic Agent ◽

Embolic Agents ◽

Liquid Embolic ◽

Liquid Embolic Agent ◽

Wide Neck

Abstract Background: Onyx HD 500 (eV3, Irvine, CA) is a high-viscosity liquid embolic agent that has recently been approved in the United States as a humanitarian use device for the treatment of wide-neck sidewall intracranial aneurysms. Preliminary evidence suggest that liquid embolic agents can provide improved angiographic results with a lower incidence of recanalization compared to coil embolization. Objective: To report unstable Onyx casts and how to deal with them. Methods: We report 4 cases of intracranial aneurysms treated with Onyx HD 500 in which, after the aneurysm was successfully obliterated, the Onyx cast was noted to have 1 of 2 types of embolic cast instability. In all 4 cases, an intracranial stent or vascular reconstruction device (VRD) was placed across the Onyx cast at the aneurysm orifice and the cast was stabilized. Conclusion: This series is the first published description of Onyx HD 500 aneurysm cast instability. It is also the first report of using a stent or vascular reconstruction device rescue technique to secure an unstable Onyx cast and represents a new indication for these devices.

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Initial experience with precipitating hydrophobic injectable liquid in cerebral arteriovenous malformations

Interventional Neuroradiology ◽

10.1177/1591019918798808 ◽

2018 ◽

Vol 25 (1) ◽

pp. 58-65 ◽

Cited By ~ 4

Author(s):

Stanimir S Sirakov ◽

Alexander Sirakov ◽

Krasimir Minkin ◽

Hristo Hristov ◽

Kristian Ninov ◽

...

Keyword(s):

Arteriovenous Malformations ◽

Endovascular Embolization ◽

Embolic Agent ◽

Initial Experience ◽

Cerebral Arteriovenous Malformations ◽

Embolic Agents ◽

Liquid Embolic ◽

Reported Study ◽

Liquid Embolic Agent ◽

Staged Treatment

Background Precipitating hydrophobic injectable liquid is a newly introduced liquid embolic agent for endovascular embolization with some technical advantages over other liquid embolic agents. We present our initial experience with precipitating hydrophobic injectable liquid in the endovascular treatment of cerebral arteriovenous malformations. Methods From October 2015 to January 2018, 27 patients harboring cerebral arteriovenous malformations underwent endovascular embolization with precipitating hydrophobic injectable liquid 25. Clinical features, angiographic results, procedural details, complications, and follow-up details were retrospectively analyzed. Results Twenty-seven patients with cerebral arteriovenous malformations were included. Total obliteration in one endovascular session was confirmed for 14/27 (52%) patients. Partial embolization was attained in 13 patients (48%) in whom staged treatment with following radiosurgery or surgery was planned. No mortality was recorded in this series. Complications during or after the embolization occurred in six of 27 (22.2%) patients. Conclusion In our initial experience, precipitating hydrophobic injectable liquid has acceptable clinical outcome comparable to other liquid embolic agents. Although this is the largest reported study in arteriovenous malformation treatment with precipitating hydrophobic injectable liquid, further studies are needed to validate its safety and efficacy.

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Preliminary experience with the liquid embolic material agent PHIL (Precipitating Hydrophobic Injectable Liquid) in treating cranial and spinal dural arteriovenous fistulas: technical note

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2015-011684 ◽

2015 ◽

Vol 8 (6) ◽

pp. 596-602 ◽

Cited By ~ 25

Author(s):

Joe J Leyon ◽

Swarupsinh Chavda ◽

Allan Thomas ◽

Saleh Lamin

Keyword(s):

Interventional Neuroradiology ◽

Technical Note ◽

Embolic Agent ◽

Embolic Material ◽

Arteriovenous Fistulas ◽

Embolic Agents ◽

Liquid Embolic ◽

Dural Arteriovenous Fistulas ◽

Fluoroscopic Time ◽

Liquid Embolic Agent

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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Embolization of a giant pediatric, posttraumatic, skull base internal carotid artery aneurysm with a liquid embolic agent

Journal of Neurosurgery Pediatrics ◽

10.3171/2009.6.peds0953 ◽

2009 ◽

Vol 4 (5) ◽

pp. 449-452 ◽

Cited By ~ 10

Author(s):

Adam S. Reig ◽

Scott Simon ◽

Robert A. Mericle

Keyword(s):

Skull Base ◽

Internal Carotid ◽

Artery Aneurysm ◽

Embolic Agent ◽

Carotid Artery Aneurysm ◽

Internal Carotid Artery Aneurysm ◽

Embolic Agents ◽

Liquid Embolic ◽

Liquid Embolic Agent ◽

The Cost

Many treatments for posttraumatic, skull base aneurysms have been described. Eight months after an all-terrain-vehicle accident, this 12-year-old girl presented with right-side Horner syndrome caused by a 33 × 19–mm internal carotid artery aneurysm at the C-1 level. We chose to treat the aneurysm with a new liquid embolic agent for wide-necked, side-wall aneurysms (Onyx HD 500). We felt this treatment would result in less morbidity than surgery and was less likely to occlude the parent artery than placement of a covered stent, especially in a smaller artery in a pediatric patient. Liquid embolic agents also appear to be associated with a lower chance of recanalization and lower cost compared with stent-assisted coil embolization. After the patient was treated with loading doses of aspirin, clopidogrel bisulfate, and heparin, 99% of the aneurysm was embolized with 9 cc of the liquid embolic agent. There were no complications, and the patient remained neurologically stable. Follow-up angiography revealed durable aneurysm occlusion after 1 year. The cost of Onyx was less than the cost of coils required for coil embolization of similarly sized intracranial aneurysms at our institution. Liquid embolic agents can provide a safe, efficacious, and cost-effective approach to treatment of select giant, posttraumatic, skull base aneurysms in pediatric patients.

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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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Emergency tips recanalisation and gastroesophageal varices embolisation with an ethylene vinyl alcohol copolymer agent (Squid) and detachable coils

European Radiology Experimental ◽

10.1186/s41747-020-00196-9 ◽

2020 ◽

Vol 4 (1) ◽

Author(s):

Massimo Venturini ◽

Luigi Augello ◽

Carolina Lanza ◽

Marco Curti ◽

Andrea Coppola ◽

...

Keyword(s):

Therapeutic Option ◽

Technical Note ◽

Embolic Agent ◽

Refractory Ascites ◽

Gastroesophageal Varices ◽

Ethylene Vinyl Alcohol ◽

Embolic Agents ◽

Liquid Embolic ◽

Tube Removal ◽

Detachable Coils

AbstractTransjugular intrahepatic portosystemic shunt (TIPS) is currently indicated as first therapeutic option in the main complications of portal hypertension, including bleeding gastroesophageal varices and refractory ascites. In case of bleeding gastroesophageal varices, an adjuvant embolisation within TIPS can be useful to prevent rebleeding. In the present technical note, the management in emergency of a patient with haemorrhagic shock due to bleeding gastroesophageal varices and occluded TIPS is reported. TIPS recanalisation with an adjunctive stent and high-pressure balloon angioplasty and gastroesophageal varices embolisation using detachable coils and a non-adhesive liquid embolic agent were performed during the same emergent procedure. After the procedure, clinical stabilisation of the patient was achieved, with blood transfusions suspension and Blakemore tube removal. At 6 months, regular TIPS patency at colour Doppler and no rebleeding episodes were recorded. To our knowledge, whilst coils are routinely used for varices embolisation, non-adhesive liquid embolic agents have been never mentioned. Liquid embolic agents seem to provide a stable plug strengthening the embolising action of the coils. Further studies involving a cohort of patients with long-term follow-up will be necessary to confirm whether this association can be more effective than coils alone in gastroesophageal varices embolisation.

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