Efficacy and limitations of transarterial acrylic glue embolization for intracranial dural arteriovenous fistulas

Bailout using NBCA for incomplete onyx embolization of tentorial dural arteriovenous fistula

Transarterial embolization using Onyx (Medtronic, Irvine, CA, USA) results in a high cure rate for complete obliteration of dural arteriovenous fistulas. However, incomplete obliteration occurs in some cases. Reports on the use of bailout therapy in such cases are limited. A 79-year-old man was diagnosed with Borden type III tentorial dural arteriovenous fistulas during a check-up for a headache. We first performed transarterial embolization with Onyx from a tentorial artery, but the fistula was not completely obliterated. We then performed an additional transarterial embolization with n-butyl-2-cyanoacrylate from the same artery in a single session, and the fistula was successfully bailed out, resulting in complete obliteration. Combining different liquid embolic materials, Onyx and n-butyl-2-cyanoacrylate, is an effective strategy for achieving complete obliteration in incomplete transarterial embolization treatment of dural arteriovenous fistulas.

Transarterial embolization in non-cavernous and cavernous sinus dural arteriovenous fistulas: A systematic review and meta-analysis of proportions

BACKGROUND

Transarterial embolization (TAE) is pivotal in managing non-cavernous and cavernous sinus dural arteriovenous fistulas (CSDAVFs).

METHODS

Systematic searches were conducted across ScienceDirect, Medline, and Cochrane databases for longitudinal studies on TAE outcomes in non-CSDAVFs and CSDAVFs. Post-procedural outcomes, including complete, incomplete, and failed AVFs obliteration, and end-study outcomes were analyzed.

RESULTS

Our meta-analysis involved 27 studies with 643 patients and 736 fistulas. Symptoms in both groups included tinnitus (29.74 %), ocular/visual symptoms (29.12 %), hemorrhage (19.42 %), and headache (19.11 %). Feeding arteries mainly originated from the meningeal arteries (49.16 %). In non-CSDAVFs cases, fistula locations were within sinus complexes (69.23 %) and specific dural areas (28.31 %). Complete AVFs obliteration was 81 % (95 %CI: 70 % - 90 %), slightly higher in non-CSDAVFs (82 %, 95 % CI: 69 % - 92 %) than CSDAVFs (79 %, 95 %CI: 58 % - 95 %). Incomplete obliteration occurred in 14 % (95 %CI: 5 % - 39 %), with rates of 11 % (95 %CI: 2 % - 26 %) in non-CSDAVFs and 19 % (95 % CI: 5 % - 39 %) in CSDAVFs. Failed obliteration was rare (1 %, 95 %CI: 0 % - 3 %), with similar rates in both groups. At end-study follow-up, resolution of AVFs was achieved in 97 % of cases (95 %CI: 92 % - 100 %). However, complications occurred in 17 % of cases (95 %CI: 10 % - 25 %), with a higher incidence in CSDAVFs (22 %, 95 %CI: 9 % - 37 %) compared to non-CSDAVFs (13 %, 95 %CI: 6 % - 23 %).

CONCLUSIONS

TAE with embolic agents demonstrates favorable outcomes in non-CSDAVFs and CSDAVFs, with high rates of AVFs obliteration and resolution. Complications, particularly in CSDAVFs, warrant careful consideration in treatment decisions.

Transarterial embolization of radicular arteriovenous fistula at the craniocervical junction

Craniocervical junction arteriovenous fistula (CCJ AVF) is a rare vascular disorder. Direct surgery for CCJ AVF is generally reported to have better outcome compared to endovascular treatment. However, no certain consensus has been obtained so far. We report a case of radicular CCJ AVF treated by transarterial embolization that resulted in a good outcome. A 69-year-old man presented with subarachnoid hemorrhage primarily in the posterior cranial fossa. Based on digital subtraction angiography showed radicular CCJ AVF with varix. Transarterial embolization was performed with n-butyl-2-cyanoacrylate on day 17 after onset and successfully cured. The neurovascular anatomy of CCJ AVF is complicated, but endovascular treatment may be a treatment option with detailed understanding of angioarchitecture and selective endovascular procedure.

LIQUID - Treatment of high-grade dural arteriovenous fistulas with Squid liquid embolic agent: a prospective, observational multicenter study

BACKGROUND

Endovascular embolization is a feasible treatment for cranial dural arteriovenous fistulas (DAVFs). New embolic agents aim to improve the success of DAVF embolization.

OBJECTIVE

To assess the safety, efficacy, and short-term outcome of the treatment of DAVFs using the new liquid embolic agent Squid.

METHODS

The LIQUID study is a prospective, observational multicenter study on the treatment of high-grade (Cognard type ≥3) DAVFs with the embolic agent Squid. The primary outcome measures were safety (ie, morbidity and mortality), as well as the occlusion rate 90 to 180 days after treatment.

RESULTS

In eight centers, 53 patients (mean age 59.8 years, 22.6% female) were treated in 55 treatment sessions. Of the DAVFs, 56.6% were Cognard type III, 41.5% type IV, and 18.9% were ruptured. Squid 18 was used in 83.6% and Squid 12 in 32.7% of the treatments. The overall rate of intraprocedural or postprocedural adverse events (AEs) was 18.2%. Procedure-related AEs resulting in permanent morbidity were observed in 3.6%. One patient (1.8%) died unrelated to the procedure due to pulmonary embolism. The final complete occlusion rate at 90 to 180 days was 93.2%. After a mean follow-up of 5.5 months, the modified Rankin Scale (mRS) score was stable or improved in 93.0%. In one of the patients, worsening of the mRS score was related to the procedure (1.8%).

CONCLUSION

Squid is a safe and effective liquid embolic agent for the treatment of high-grade DAVFs.

Retrieval of N-Butyl-2-Cyanoacrylate Glue Migrated to the Vertebral Artery via Dangerous Anastomosis, Using the Stent-Retriever Aspiration Technique, during Dural Arteriovenous Fistula Embolization: A Case Report

Objective

We report a case of accidental N-butyl-2-cyanoacrylate (NBCA) glue migration into the vertebral artery (VA) via dangerous anastomosis during transarterial embolization (TAE) for transverse sinus (TS)-dural arteriovenous fistula (DAVF), which was rescued by mechanical retrieval using a stent retriever and aspiration devices.

Case Presentation

A 49-year-old right-handed female patient was admitted to our hospital with motor aphasia. MRI revealed congestion in the left temporal and occipital lobes, involving a small hemorrhage. DSA revealed a DAVF complicated by a sinus thrombus in the left TS. The DAVF was mostly fed by the left occipital artery (OA) and drained into the cortical veins of the temporal and occipital lobes through the patent part of the sinus. TAE was performed via the left OA with low-concentration NBCA. However, NBCA glue migrated into the left VA through a dangerous anastomosis, and a left VA angiogram revealed severe VA stenosis and floating NBCA glue. There was a fragile attachment of the NBCA glue to the arterial inner wall; therefore, we successfully retrieved the NBCA glue with a stent retriever and aspiration devices without complications. Finally, TAE was performed using another feeder, and the DAVF was completely obliterated.

Conclusion

TAE using NBCA is useful for the treatment of DAVF; however, it should be noted that there is a risk of migration via potential anastomotic routes. Low-concentration NBCA glue can be retrieved using these devices in limited cases.

Endovascular Management of Intracranial Dural Arteriovenous Fistulas: Transarterial Approach

In this second of 3 review articles on the endovascular management of intracranial dural AVFs, we discuss transarterial treatment approaches. The treatment goal is to occlude the fistulous point, including the most distal portion of the arterial supply together with the most proximal portion of the draining vein (ie, the "foot" of the vein), which can be accomplished with liquid embolic agents via transarterial access. Anatomic factors to consider when assessing the safety and efficacy of a transarterial approach using liquid embolic agents include location, angioarchitecture, and proximity of arterial feeders to both the vasa nervosum of adjacent cranial nerves and the external carotid-internal carotid/vertebral artery anastomoses. Anatomic locations typically favorable for transarterial approaches include but are not limited to the transverse/sigmoid sinus, cerebral convexity, and superior sagittal sinus. In this review article, we discuss the technical approaches, outcomes, potential complications, and complication avoidance strategies for transarterial embolization.

Endovascular treatment of medullary bridging vein-draining dural arteriovenous fistulas: foramen magnum vs. craniocervical junction lesions

PURPOSE

Dural arteriovenous fistulas (AVFs) draining to medullary bridging vein (MBV) are located at foramen magnum (FM) and craniocervical junction (CCJ). Such fistulas are rare but pose a challenge to endovascular management. This study was undertaken to assess clinical manifestations, angiographic features, and outcomes of endovascular treatment in patients with MBV dural AVFs.

METHODS

A number of our patients (N = 22) were diagnosed with MBV dural AVF and treated by endovascular means. There were 9 FM lesions and 13 CCJ lesions. We reviewed clinical records and imaging studies to define clinical characteristics, vascular anatomic details, and treatment outcomes, comparing FM- and CCJ-level subsets.

RESULTS

Subjects ranged from 37 to 74 years of age (mean, 57.7 years) with male predominance (2.7:1). They presented with intracranial hemorrhage (11/22, 50%), myelopathy (8/22, 36%), or nonspecific symptoms (3/22, 14%). In 17 patients (77.3%), the shunts showed complete or near-complete occlusion following endovascular treatment (FM, 100%; CCJ, 61.5%). However, seven patients experienced ischemic events (FM, 11.1%; CCJ, 46.2%) and one patient sustained a hemorrhagic complication. No hemorrhages recurred during follow-up monitoring, and myelopathic symptoms abated.

CONCLUSION

MBV dural AVFs are highly aggressive lesions for which proper diagnosis and treatment are of utmost importance. Although transarterial embolization proved highly successful in FM lesions, shunt occlusion was less frequent in the CCJ subset, with greater risk of ischemic complications.

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.

Long-term follow-up of transarterial balloon-assisted Onyx embolization for endovascular treatment of dural arteriovenous fistulas: A single-institution case series and literature review

OBJECTIVE

Dural arteriovenous fistulas (DAVFs)-specifically, symptomatic DAVFs with cortical venous reflux-are aggressive lesions with a poor prognosis. Intra-arterial endovascular closure is considered the optional treatment for DAVFs and is currently performed at several international centers. However, long-term outcomes remain unknown. This study investigated the long-term efficacy and safety of transarterial balloon-assisted Onyx embolization in the treatment of DAVFs.

METHODS

A total of 14 consecutive patients who underwent endovascular treatment for DAVFs were treated by balloon-assisted Onyx embolization. Additionally, we retrospectively reviewed all cases reported in the literature and compared the outcomes of patients treated with single- vs dual-lumen microcatheters.

RESULTS

The patients at our institution were followed-up for 114.57 ± 33.52 months. Embolization was performed by balloon-assisted Onyx injection via a single feeding artery. Complete occlusion was achieved in 13 cases and partial occlusion in 1 case. At the final follow-up, all patients were functionally independent (Modified Rankin Scale score of 0-2), with no recurrence. In our review of 70 published cases of DAVFs that underwent endovascular treatment by balloon-assisted Onyx embolization, single- and dual-lumen balloon catheters were used in 33 and 37 patients, respectively. In the former group, there was complete or near-complete occlusion in 32 cases and partial occlusion in 1 case; and in the latter, there was complete or near-complete occlusion in 35 cases and partial occlusion in 2 cases. There were no deaths following endovascular treatment.

CONCLUSION

Measurable and durable outcomes can be achieved by endovascular treatment of DAVFs with the transarterial balloon-assisted Onyx embolization technique, especially in cases with small, distal, and circuitous feeding arteries.

A Comprehensive Analysis of Dural Arteriovenous Fistula Involving the Superior Sagittal Sinus: A Systematic Review

Objective

To evaluate published papers concerning dural arteriovenous fistula involving the superior sagittal sinus (SSS dAVF) treated with endovascular intervention.

Methods

A literature review was performed to identify studies reporting the clinical characteristics, vascular anatomy, endovascular techniques, embolic materials, angiographical result, and outcomes of SSS dAVF.

Results

The analysis consisted of 40 case reports or series, comprising a total of 51 cases of SSS dAVF treated with endovascular intervention. Clinical symptoms included hemorrhage (29.4%), infarction (17.6%), and seizure (7.8%). The arterial supply included the middle meningeal artery (MMA) (100%), superficial temporal artery (STA) (62.7%), and occipital artery (OA) (49.0%). Bilateral MMAs supplied in 78.4% of the cases. A pial arterial supply was observed in 21.6% of the cases. Stenosis or occlusion of the sinus was seen in 37.3% of the cases. The distribution of the Borden classification was as follows: I (7.8%), II (37.3%), and III (54.9%). The endovascular techniques were transvenous embolization (TVE) alone (11.8%), transarterial embolization (TAE) alone (74.5%), and a combination thereof (13.7%). The types of embolic materials for TAE were a coil (25.5%), n-butyl-2-cyanoacrylate (NBCA) (33.3%), and Onyx (45.1%). The arterial pedicles for TAE included MMA (86.3%), STA (17.6%), and OA (9.8%). Direct surgical exposure for the alternative endovascular access was performed to the SSS (5.9%), MMA (3.9%), STA (5.9%), and OA (3.9%). Sinus angioplasty with or without stenting was done in 9.8% of the cases. Balloon-assisted Onyx TAE was done with proximal flow control (7.8%), collateral devascularization (5.9%), and sinus protection (3.9%). Complete occlusion was achieved in 86.3% of the cases while the number of endovascular sessions varied among patients: single (74.5%), double (15.7%), and triple (9.8%). The rate of a postoperative modified Rankin Scale (mRS) score of 0-2 was 89.3%, with morbidity and mortality rates of 7.8% and 3.9%, respectively. Two patients died, possibly due to postoperative acute SSS occlusion.

Conclusion

The current systematic review disclosed several specific results, namely, the angioarchitectures of the SSS dAVF, the relationship between classification and hemorrhagic presentation, the diversity of treatment techniques, the association between the complete occlusion rate and the SSS condition, and the difficulty of achieving curable occlusion in a single session. These findings underscore the need for the development of endovascular techniques and devices to treat this challenging lesion. Improvements in adjunctive endovascular procedures, such as balloon-assisted techniques for Onyx TAE, may help support to the safe and effective obliteration of SSS dAVF.

Outcomes After Onyx Embolization as Primary Treatment for Cranial Dural Arteriovenous Fistula in the Past Decade

RATIONALE AND OBJECTIVES

This retrospective single-center study aims to evaluate endovascular therapy (EVT) of cranial dural arteriovenous fistulas (dAVF) with ethylene vinyl alcohol (EVOH) copolymer (Onyx) regarding occlusion rates, complications, and recurrences.

MATERIAL AND METHODS

From January 2008 to April 2018, 75 patients with dAVF (41 men, 34 women; mean age 56 years) underwent EVT with the nonadhesive liquid embolic agent as primary treatment. Patient records and angiograms were reviewed for demographic data, symptoms, fistula type and size, number of EVTs, amount of embolic material, occlusion rates, and recurrences.

RESULTS

Seventy-five patients with dAVFs were primarily embolized with EVOH in 96 EVTs. According to the Merland-Cognard classification the majority of dAVFs treated were type 4 (42.7%), followed by type 2a (18.7%), type 2a+b (17.3%), type 1 (8%), type 2b (5.3%), type 3 (5.3%), and type 5 (2.7%). Complete occlusion (CO) of the dAVF was achieved in 45/75 (60%) of cases after a single EVT and in 58 (77%) patients after one or several EVTs. Seven patients (9%) required additional surgical therapy for CO. Successful treatment was achieved for 70/75 (93%) patients including 10 (13%) patients with residual dAVFs type 1-2a. Recurrence after CO occurred in one (1.3%) patient and four (5.3%) patients remained refractory to therapy with dAVFs type > 2a. Procedure-related permanent morbidity occurred in 4/75 (5.3%) patients.

CONCLUSION

For more than a decade transarterial EVOH embolization has established as the first-line treatment for cranial dAVFs with high cure rates and low rates of complications and recurrences. Additional neurosurgical therapy is rarely required for curative treatment.

Embolization of cranial dural arteriovenous fistulas in the liquid embolic era: A Sydney experience

Endovascular management of dural arteriovenous fistulas has become a mainstay of treatment. In particular, modern techniques have allowed greater fistula penetration and likelihood of complete obliteration. However, the efficacy of newer agents has not been quantified outside of predominantly small case reports and case series. Furthermore, the Australian experience with fistula embolization has yet to be reported in the literature. To this aim, we performed a retrospective review of our endovascular management of a large cohort of cranial dural arteriovenous fistulas in the liquid embolic era. This retrospective case series included ninety-six consecutive patients of any Cognard grade, treated between 2005 and 2016. Liquid embolic agents were used exclusively in eighty-three cases. The overall complete obliteration rate was 89.6% with a residual fistula rate of 2%, and complication rate of 8.3%. This Sydney, Australia cohort demonstrates excellent treatment effect and safety outcomes and thus supports the primary treatment of this condition by endovascular means.

Safety of Onyx Transarterial Embolization of Skull Base Dural Arteriovenous Fistulas from Meningeal Branches of the External Carotids also Fed by Meningeal Branches of Internal Carotid or Vertebral Arteries

PURPOSE

To analyze the angiographic and clinical results of transarterial embolization with Onyx (Medtronic-Covidien, Irvine, CA) in dural arteriovenous fistulas (DAVFs) partially fed by arteries arising from the carotid siphon or the vertebral arteries.

METHODS

We isolated 40 DAVFs supplied by either the tentorial artery of the internal carotid artery (ICA) or the posterior meningeal artery of the vertebral artery. These DAVFs were embolized with Onyx through the middle meningeal artery or the occipital artery. We reviewed the occurrence of reflux into the arteries of carotid or vertebral origin.

RESULTS

In all the cases, reflux occurred into the first millimeters of the DAVF arterial feeders arising from carotid or vertebral arteries but slowly enough to be controlled by interruption of Onyx injection. Reflux was always minimal and Onyx never reached the ostium of the arteries. No cerebral ischemic complications occurred in our series.

CONCLUSION

The behavior of Onyx is clearly different from that of cyanoacrylate glue, resulting in superior control during injection. Reflux into arteries arising from the ICA or vertebral artery during DAVF treatment always carries a risk of unintentional non-target embolization of normal cerebral vasculature but Onyx appears to be safe in this situation.

Middle meningeal artery: Gateway for effective transarterial Onyx embolization of dural arteriovenous fistulas

Curative transarterial embolization of noncavernous sinus dural arteriovenous fistulas (dAVFs) is challenging. We sought to evaluate the role of the middle meningeal artery (MMA) in endovascular treatment of these lesions. We performed a retrospective cohort study on patients who underwent transarterial Onyx embolization of a noncavernous sinus dAVFs with contribution from the MMA at a major academic institution in the United States from January 2009 to January 2015. Twenty consecutive patients who underwent transarterial Onyx embolization of a noncavernous sinus dAVF were identified. One patient was excluded as there was no MMA contribution to the dAVF. All of the remaining 19 patients (61.3 ± 13.8 years of age) underwent transarterial embolization through the MMA. Six patients (31.6%) presented with intraparenchymal or subarachnoid hemorrhage from the dAVF. The overall angiographic cure rate was 73.7% upon last follow up. In 71.4% of successfully treated patients transarterial embolization of the MMA alone was sufficient to achieve angiographic cure. When robust MMA supply was present, MMA embolization resulted in angiographic cure even after embolization of other arterial feeders had failed in 92.9% of patients. A robust contribution of the MMA to the fistula was the single most important predictor for successful embolization (P = 0.00129). We attribute our findings to the fairly straight, non-tortuous course of the MMA that facilitates microcatheter access, navigation, and Onyx penetration. Noncavernous sinus dAVF can be successfully embolized with transarterial Onyx through the MMA, as long as supply is robust. A transvenous approach is rarely necessary. Clin. Anat. 29:718-728, 2016. © 2016 Wiley Periodicals, Inc.

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

BACKGROUND

Liquid 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.

OBJECTIVE

To present our preliminary experience using PHIL in treating cranial and spinal DAVFs.

METHODS

Between 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.

RESULTS

Seven 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.

CONCLUSIONS

PHIL 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.