Prospective Study of Polytetrafluoroethylene-Covered Microplugs and Detachable Coils for Embolization of Pulmonary Arteriovenous Malformations: Technical Results, Procedure Times, and Costs.

PURPOSE: To determine time to occlusion and procedure costs of embolization of pulmonary arteriovenous malformations (PAVMs) using a polytetrafluoroethylene-covered microplug compared with embolization using detachable coils. MATERIALS AND METHODS: In this prospective study, 37 patients (mean age, 39.1 years [SD ± 17.6]) with 82 PAVMs underwent embolization with microplug or detachable coils between April 2019 and January 2023. Technical success, procedure time intervals, and costs were analyzed. RESULTS: In 37 patients, 82 PAVMs and 101 feeding arteries were successfully treated (microplug, 64; microplug + another device, 5; detachable coils alone, 32). Time from embolic device inserted into the catheter to device deployed and time to occlusion differed significantly between microplug and detachable coil cohorts (P < .0001 for both). Embolization with ≥1 microplug had a significantly shorter occlusion time than embolization with detachable coils (median, 10.0 minutes saved per feeding artery) (P < .0001). Compared with detachable coil embolization, microplug embolization saved a median of 9.0 minutes per feeding artery (P < .0001) and reduced room cost by a median of $429 per feeding artery (P < .0001). Device costs per feeding artery did not differ significantly between microplug ($2,790) and detachable coil embolization ($3,147) (P = .87). CONCLUSIONS: Compared with coils, microplugs had an equally high technical success rate but significant time to occlusion and room costs savings per feeding artery. Total room cost and device cost together did not differ significantly between microplugs and coils. Microplugs may be considered technically effective and at least cost-neutral for PAVM embolization where clinically appropriate.

Transarterial Embolization of Renal Arteriovenous Malformations: Treatment Outcomes According to Angiographic Classification.

PURPOSE: To assess the different adjunctive catheter techniques required to achieve complete occlusion of renal arteriovenous malformations (rAVMs) of different angioarchitectural types. MATERIALS AND METHODS: Overall, data on 18 patients with rAVM (Type 1, n = 7; Type 2, n = 2; Type 3, n = 9; mean age, 53.8 years) who underwent 25 procedures between 2011 and 2022 were reviewed. The clinical presentations, endovascular techniques, arteriovenous malformation (AVM) occlusion rate, adverse events (including the incidence of renal infarction), and clinical symptoms and outcomes (including recurrence/increase of AVM) were analyzed according to the Cho-Do angioarchitectural classification. Posttreatment renal infarction was classified as no infarction, small infarction (<12.5%), medium infarction (12.5%-25%), and large infarction (>25%) using contrast-enhanced computed tomography or magnetic resonance imaging. RESULTS: Hematuria and heart failure were presenting symptoms in 10 and 2 patients, respectively. The embolic materials used were as follows: Type 1 rAVM, coils alone or with n-butyl-2-cyanoacrylate (nBCA); Type 2 rAVM, nBCA alone or with coils; and Type 3 rAVMs, nBCA alone. Fourteen patients underwent adjunctive catheter techniques, including flow control with a balloon catheter and multiple microcatheter placement, alone or in combination. Immediate postprocedural angiography revealed complete occlusion in 15 patients (83%) and marked regression of rAVM in 3 (17%). Small asymptomatic renal infarctions were observed in 6 patients with Type 3 rAVMs without any decrease in renal function. No major adverse events were observed. All symptomatic patients experienced symptom resolution. Recurrence/increase of rAVM was not observed during the mean 32-month follow-up period (range, 2-120 months). CONCLUSIONS: Transarterial embolization using adjunctive catheter techniques according to angioarchitectural types can be an effective treatment for rAVMs.

Ophthalmic artery occlusion following n-butyl cyanoacrylate embolization of an orbital arteriovenous malformation.

A 33-year-old pregnant woman presented with six months of right-sided proptosis. Neuroimaging revealed a right orbital arteriovenous malformation arising from the second segment of the ophthalmic artery. As she was 9 weeks pregnant, the decision was made to monitor her closely. Over the following six months, her proptosis progressed, accompanied by decreased visual acuity, afferent pupillary defect, and red desaturation concerning for compressive optic neuropathy. After planned c-section, she underwent embolization with n-butyl cyanoacrylate. Upon awakening after embolization, she had no light perception vision from her right eye and was found to have ophthalmic artery obstruction. She ultimately developed a blind painful right eye and underwent enucleation with histopathology demonstrating glue in the central retinal artery, posterior ciliary arteries, and choroid. This case highlights ophthalmic artery occlusion as a rare complication of orbital arteriovenous malformation embolization and demonstrates correlating histopathological findings, which have not previously been reported.

Embolization for Arteriovenous Malformations in the Maxilla With Coils and Ethanol.

PURPOSE: Maxillary arteriovenous malformations (AVMs) are uncommon, limiting comprehensive research into standard treatment protocols. This study evaluated the management, outcomes, and clinical safety of embolization techniques for maxillary AVMs, using coils and ethanol. METHODS: In this retrospective case series, we enrolled a sample of patients with maxillary AVMs treated with embolization using coils with or without ethanol between June 2017 and July 2019. Coils were super-selectively placed into the nidus and dominant outflow vein to decrease the flow of the arteriovenous fistulas. Absolute ethanol was then injected to obliterate the nidus. Clinical follow-up was performed for all the patients, and therapeutic outcomes were measured by evaluating the degree of devascularization and symptoms. RESULTS: Ten patients were included in the present study, including 4 men (40%) and 6 women (60%), with a mean age of 18.1 years (range, 10 to 36 years). Transvenous release of coils (9 detachable coils and 143 pushable coils), either with or without absolute ethanol embolization, was used in all the patients. The amount of ethanol injected ranged from 0 to 12 mL (mean: 6.5 mL; 95% confidence interval: 3.489 to 9.511) in a single session. Seven (70%) of the 10 patients were cured, while 3 patients (30%) had partial remission. Follow-up times ranged from 26 to 42 months (median: 29.7 months). Tooth loosening and coil exposure occurred in 7 patients (70%) and healed after surgery. No major complications were noted. CONCLUSIONS: Coils and ethanol embolization have the potential to cure AVMs in the maxilla with an acceptable risk of minor complications.

Lingual Arteriovenous Malformation With Bleeding Treated With Polidocanol Foam Sclerotherapy Using Intestinal Forceps to Control Blood Flow.

ABSTRACT: Arteriovenous malformation (AVM) sometimes causes hemorrhage that can be fatal. We report a case of AVM of the tongue with bleeding that was treated by semi-emergent sclerotherapy with polidocanol. A 33-year-old woman presented with Schobinger stage III AVM of the tongue. Sclerotherapy with 3% polidocanol foam was performed under general anesthesia using curved intestinal forceps to clamp the root of the tongue for control of blood flow. Postoperatively, there was no further bleeding from the lesion. Three subsequent sclerotherapy sessions with polidocanol were performed, and there was a marked reduction in the size of the lesion. The lesion has remained well controlled in the year since the last sclerotherapy session.

Therapeutic outcomes of embolotherapy of extremity bone intraosseous arteriovenous malformation with ethanol, coils, and n-butyl cyanoacrylate.

OBJECTIVE: We evaluated the therapeutic outcomes of embolotherapy for bone arteriovenous malformations (AVMs) affecting the extremities using ethanol, coils, and n-butyl cyanoacrylate (NBCA). METHODS: We reviewed the data from 36 patients (18 males, 18 females; mean age 25 years; age range, 1-64 years) with bone AVMs affecting their extremities who had undergone embolotherapy using ethanol, coils, and NBCA from December 1996 to July 2019. Of the 36 patients, 19 had had pure bone AVMs and 17 mixed bone and soft tissue (MBS) AVMs. Embolotherapy was performed using direct puncture or a transvenous or an intra-arterial approach (range, 1-18 procedures; mean, 5 procedures). During the 178 embolotherapy procedures, ethanol was used in all 36 patients, except for 1. Coils were used in 14 patients, and NBCA and a lipiodol mixture in 9 patients. The therapeutic outcomes were evaluated by the clinical symptom response and the degree of devascularization on follow-up angiography or computed tomography. The major and minor complications were also evaluated. RESULTS: The clinical success (cure or markedly improvement) rate of embolotherapy for pure bone AVMs was significantly better than that for the MBS AVMs (88% vs 18%; P < .001). The complete devascularization rate of the bone AVM component of the MBS AVMs was 71%; however, the cure rate of the MBS AVMs was 0% owing to the remaining soft tissue AVMs. Of the 36 patients, 12 experienced complications, including 11 minor (2 skin bullae formation and 10 transient peripheral nerve injury) and 1 major (longstanding nerve palsy). CONCLUSIONS: Embolotherapy for bone AVMs affecting the extremities using ethanol, coils, and an NBCA mixture is effective and safe for the resolution or improvement of symptoms, especially in those with pure bone AVMs.

Safety and Effectiveness of Ethylene Vinyl Alcohol Copolymer Embolization of Peripheral High-Flow Arteriovenous Malformations: Results of a Prospective Study.

PURPOSE: To prospectively evaluate the efficacy and safety of a new ethylene vinyl alcohol (EVOH) copolymer-based embolic agent in the treatment of symptomatic peripheral arteriovenous malformations (AVMs). MATERIALS AND METHODS: This prospective single-center study evaluated EVOH embolization with 3 different formulations of EVOH (Squid Peri 12 cP, 18 cP, and 34 cP; BALT Germany GmbH, Düsseldorf, Germany) in patients with symptomatic AVMs. Between April 2018 and October 2019, 36 embolization procedures in 21 patients (3 males and 18 females; mean age, 34.7 years) were performed (inclusion criteria: symptomatic peripheral AVM, ≥14 years of age, and elective embolization). Symptoms, technical aspects (transarterial, transvenous, or percutaneous approach; plug or balloon occlusion), clinical and technical success (defined as the improvement of symptoms and complete angiographic eradication of the AVM nidus), adverse events, and short-term outcomes were assessed. RESULTS: The mean volume of the embolic agent used per session was 3.4 mL of EVOH 34 cP (standard deviation [SD], ± 5.4), 6.2 mL ± 8.1 of EVOH 18 cP, and 4.6 mL ± 10.1 of EVOH 12 cP. Angiographic success was achieved in 18 patients (85.7%). The mean follow-up was 190 days (range, 90-538 days; median, 182 days). In the follow-up assessment, findings of magnetic resonance imaging showed that 19 patients (90.5%) had a persistent state of devascularization compared with postinterventional angiography. Amelioration or complete elimination of pain was achieved in 90.0% of the patients. One patient experienced a major adverse event; minor adverse events developed in 2 patients. CONCLUSIONS: In this study, EVOH appeared to be a safe and effective embolic agent in peripheral AVMs and had a low rate of adverse events in a limited number of patients.

A Rare Case of Dysplastic Axillary Artery Aneurysm Associated with Arteriovenous Malformation.

BACKGROUND: Axillary artery aneurysms are rare conditions, and their causes are various. They can determine severe complications, so the treatment is extremely important. METHODS: We report the case of a young man affected by a saccular axillary artery aneurysm associated with intramuscular arteriovenous malformation, without symptoms except for the presence of a pulsatile mass. Duplex scan and computed tomography scan have been essential for a correct diagnosis and planning of the treatment. At first, the patient was submitted to coil embolization of an efferent vessel, and then he was treated surgically through ligation and detachment of the aneurysm and replacement of part of the axillary artery with a Dacron graft (Vascutek, Inchinnan, Renfrewshire, Scotland, UK). RESULTS: Follow-up at 1 and 6 months revealed normal patency of the axillary arterty and the prosthetic graft with complete exclusion and thrombosis of the aneurysm sac.No sensitive nor motor deficit were observed. CONCLUSIONS: Aneurysms of the axillary artery associated with intramuscular arteriovenous malformations are very rare, but have to be suspected. The treatment is challenging and can be surgical, endovascular, or hybrid, based on the patient's conditions and aneurysm's anatomical features.

Endodontic implications of a patient with arteriovenous malformation: a case report and literature review.

AIM: To present the endodontic management of a patient diagnosed with a high-flow arteriovenous malformation (AVM) requiring root canal treatment and to discuss the relevant endodontic literature for this rare but significant problem. SUMMARY: AVM is a complex communication of an artery and a vein in which the oxygenated blood is forced away from the intended tissue. The incidence of its occurrence in the face and neck is rare, and when present, the most common sign is gingival bleeding. Arteriovenous malformation is both a diagnostic and therapeutic challenge for dentists. Also, there is ambiguity regarding the precautions to be taken whilst doing endodontic procedures in such cases. Hence, there is a need to understand the disease process and its implications in order to prevent life-threatening complications during treatment. This case report highlights the successful endodontic management of a cariously exposed right maxillary second premolar in a patient diagnosed with high-flow AVM. On an orthopantomogram, the AVM was spreading in the left submandibular space involving the left ramus area. The clinical findings of limited mouth opening with inter-appointment swelling and trismus during treatment made the case unusual and challenging. This paper addresses the current understanding of the classification, diagnosis, clinical features and endodontic management, together with specific guidelines and recommendations whilst performing endodontic procedures in AVM cases. KEY LEARNING POINTS: The classification and oral manifestations of AVM must be known and understood. Practitioners should be aware of the radiographic appearance of AVM. Recommended precautions should be taken when carrying out restorative and endodontic procedures in a patient with AVM. Antibiotic prophylaxis may be considered before endodontic treatment in a patient with AVM. Multidisciplinary treatment planning may be required.

Embolization of peripheral arteriovenous malformations and fistulas with precipitating hydrophobic injectable liquid (PHIL®).

PURPOSE: This paper reports on the preliminary experience of a single center in the embolization of peripheral AVMs and fistulas with precipitating hydrophobic injectable liquid (PHIL®), focusing on technical aspects and short-term clinical outcomes. MATERIALS AND METHODS: Seven males and five females were included in this study, mean age 42.16 years. For ten of them, it was the first embolization treatment; two had been previously treated with Onyx® embolization. PHIL® was injected with a transarterial approach without other embolics during the same procedure. Lesions were localized in small bowel (1), colon (1), head face (5), forefoot (1), uterus (1) and thorax (3); all were symptomatic. After 30-day clinical follow-up, a contrast-enhanced CT or MR was acquired at 3 months from intervention to detect eventual lesion residual. RESULTS: After a single embolization procedure, complete technical success was obtained in 50%, while clinical improvement without additional therapies was appreciable in all patients. No technical failure occurred; in two cases, a small amount of PHIL® proximally refluxed in nontarget vessels without clinical effects. No tattooing effects of superficial lesions neither artifacts at CT and cone-beam CT controls were evident. CONCLUSIONS: PHIL® seems to be a safe and effective liquid embolic agent for the treatment of peripheral AVMs and fistulas; although a direct comparison between PHIL and Onyx was not performed, PHIL might present the advantages of reduced artifacts at postprocedural CT scan and no need for shaking time preparation, but it is more expensive due to lower volume of product for each package and slightly less radiopaque at fluoroscopy.

Inline Balloon Occlusion-Assisted Delivery of Ethylene Vinyl Alcohol Copolymer for Peripheral Arterial Applications: A Multicenter Case Series.

PURPOSE: To assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications. MATERIALS AND METHODS: Six academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11-94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1-5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications. RESULTS: Balloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred. CONCLUSIONS: Balloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).

Retrospective Comparison of Pulmonary Arteriovenous Malformation Embolization with the Polytetrafluoroethylene-Covered Nitinol Microvascular Plug, AMPLATZER Plug, and Coils in Patients with Hereditary Hemorrhagic Telangiectasia.

PURPOSE: To evaluate effectiveness of the polytetrafluoroethylene-covered nitinol mesh microvascular plug (MVP) and compare it with other devices in pulmonary arteriovenous malformation (PAVM) embolization in patients with hereditary hemorrhagic telangiectasia (HHT). MATERIALS AND METHODS: Twenty-five patients (average age 35 y; range, 15-56 y) with hereditary hemorrhagic telangiectasia (HHT) and de novo PAVM embolization with at least 1 MVP between November 2015 and May 2017 were retrospectively evaluated. Retrospective data were also obtained from prior embolization procedures in the same patient population with other embolic devices dating back to 2008. Technical success, complications, PAVM persistence rates, and category of persistence were analyzed. RESULTS: In 25 patients, 157 PAVMs were treated: 92 with MVP, 35 with AMPLATZER vascular plug (AVP), 6 with AVP plus coils, and 24 with coils. The per-PAVM technical success rates were 100% with MVP; 97%, AVP; 100%, AVP plus coils; and 100%, coils. PAVM persistence rates and median follow-up were as follows: MVP, 2% (1/92) (510 d); AVP, 15% (3/20) (1,447 d); AVP plus coils, 20% (1/5) (1,141 d); coils, 46.7% (7/15) (1,141 d). Persistence owing to recanalization for MVP, AVP, AVP plus coils, and coils was 2%, 15%, 0%, and 33%. No difference was found between persistence rates of MVP vs AVP (P = .098). Embolization with a vascular plug (MVP or AVP) with or without coils had a statistically significant lower persistence rate (5.4%) than embolization with coils alone (46.7%) (P = .022). CONCLUSIONS: PAVM embolization with MVP had a high technical success rate and a low persistence rate comparable to AVP and lower than coil embolization alone.

An Interdisciplinary Approach to Treatment of Adult Facial Arteriovenous Malformations: A Review of the Literature and A Single Institution's Experience With "Late" Surgical Resection and Aesthetic Reconstruction.

BACKGROUND: Arteriovenous malformations (AVMs) are high flow vascular anomalies that are difficult to manage given their high recurrence rate. At this time, the optimal treatment of AVMs involves embolization and surgical resection. However, few studies have examined patient outcomes after a delayed surgical resection approach. METHODS: A retrospective chart review of all patients presenting to a single institution with vascular malformations from 2000 to 2016 was performed. Patients with facial AVMs that underwent operative management were included. Records were reviewed for patient characteristics, lesion natural history, operative timing after embolization (<72 vs >72 hours), and outcomes. RESULTS: 11 patients fulfilled the inclusion/exclusion criteria. Nine patients were female, with an average age at resection of 29.1 years. Three patients had hemi/mid-facial AVMs, 1 patient had a nasal AVM, 3 patients had labial AVMs, 1 patient had an AVM on the chin, and 1 had a periorbital AVM. Average time between embolization and primary resection was 8.6 days (range 1-24). No complications requiring reoperation occurred in any patient. Average follow-up was 32.6 months, with 2 recurrences at a mean of 47.6 months. Timing of resection, Schobinger stage, and resection completeness did not significantly affect recurrence (P >0.05). Lesion size >6 cm in any dimension was significantly associated with recurrence (P = 0.018). CONCLUSION: Compared to early resection, delayed (>72 h) surgical resection after embolization of facial AVMs is a viable treatment option and results in non-inferior recurrence rates (25 vs 14% respectively over a 40-month period).

Transarterial embolization of peripheral high-flow arteriovenous malformation with ethylene vinyl alcohol copolymer (Onyx®): single-center 10-year experience.

PURPOSE: High-flow arteriovenous malformations (AVMs) are complex vascular lesions for which transcatheter embolization is considered as first-choice treatment nowadays. Multiple embolizing agents have been described, and among them, Onyx® seems to be promising; this is a liquid embolic agent, originally applied in neurointerventional radiology and recently adopted also in peripheral embolizations. The aim of this study is to report on a 10-year experience of transarterial embolization of peripheral high-flow AVM with Onyx® in terms of technical and clinical outcomes. MATERIALS AND METHODS: Retrospective analysis was conducted on patients affected by high-flow AVM and treated electively by transarterial embolization with Onyx®. Data collection included: preinterventional clinical radiological evaluations, procedural data and post-procedural clinical radiological assessment. Technical and clinical success was evaluated; follow-up was conducted 30 days after the last treatment session and yearly in case of success. RESULTS: Sixteen patients have been included, totally 38 embolizing procedures. Additional embolizing agents were required in 5 patients. Technical success was obtained in 11 patients; at 30-day follow-up, 15 patients showed improvements in symptoms, even those with incomplete embolization; however, after almost 1 year from treatment accomplishment, 7 patients showed relapse of symptoms and presented radiological signs of AVM recurrence. No clinically relevant complications occurred. CONCLUSIONS: In this series, in accordance with previous but limited published data, Onyx® appeared safe and technically effective to embolize high-flow peripheral AVM with transarterial approach. Clinical radiological follow-up is mandatory because new feeder recruitment has to be expected; patients should be informed of the concrete possibility of multiple treatment sessions.

Embolization as the Primary Treatment for Mandibular Arteriovenous Malformations: An Analysis of 50 Literature Reports and of an Illustrative Case.

PURPOSE: The aim of the present report is to describe 50 cases in the literature of mandibular arteriovenous malformations (AVMs) in which embolization was the primary treatment and to discuss details such as age, gender, materials used, outcome of embolization, time of follow-up, and intra- or postprocedure complications. An illustrative case in which reossification was noticed after embolization also is presented. PATIENTS AND METHODS: The study was carried out in 2 steps. In the first, an electronic search without time restriction for embolization as the primary treatment for mandibular AVMs was performed on Medline through PubMed. In the second, the case of a patient with mandibular AVM and massive oral bleeding episodes is described after a long-term follow-up. RESULTS: Clinical stability with the cessation of oral bleeding episodes was detected in 25 cases and 2 cases were planned for another embolization session. Clinical stability and reossification were detected in 23 of the 50 cases included. Complications were reported in 50% of cases, but most were minor and transient. CONCLUSION: Currently, owing to more sophisticated imaging techniques, the diagnosis of mandibular AVMs is quicker and new, less invasive techniques that avoid surgical resection have proved effective. It should be emphasized that these techniques are not without complications and that long-term monitoring is extremely important.

Direct stick embolization of extremity arteriovenous malformations with ethylene vinyl alcohol copolymer.

Direct stick embolization (DSE) of high-flow peripheral arteriovenous malformations (AVMs) has previously been reported using n-butyl cyanoacrylate and ethanol. The use of ethylene vinyl alcohol copolymer (Onyx; Covidien, Plymouth, Minn) through this delivery route has been extremely limited, particularly in the peripheral interventional realm, owing to concerns about technique and conduit for delivery, skin discoloration, and ulceration. We describe three patients with relatively focal, symptomatic, congenital high-flow AVMs of the upper and lower extremity treated successfully by multifaceted approaches including transvenous coil embolization of the nidus venous outflow, transarterial embolization, and DSE of the AVM nidus with Onyx. Successful delivery of Onyx into the AVM nidus was achieved without nontarget embolization. Sustained symptomatic relief without recurrence or associated complications was achieved at 1 month, 3 months, and 6 months of follow-up. Nidus embolization is a key technical maneuver for optimal treatment of high-flow AVMs, although it is not always easily achievable by the transarterial route in more extensive, convoluted angioarchitectural varieties. With appropriate technical considerations and precautionary measures, Onyx can be safely and effectively delivered through DSE into the AVM nidus with satisfactory short-term and midterm clinical outcomes. This maneuver expands the armamentarium of the treating vascular surgeon facing complicated peripheral AVMs.

A novel, non-adhesive, precipitating liquid embolic implant with intrinsic radiopacity: feasibility and safety animal study.

OBJECTIVES: To evaluate a novel, ready-to-use, iodinated polyvinyl alcohol polymer embolic implant. METHODS: Under good laboratory practice conditions, 26 pigs were investigated. A complex arteriovenous malformation (AVM) model was created in 16 animals, and a simple rete model was used in the remaining 10 animals. The novel material was used for embolization in 22 animals, and a commercially available liquid embolic material in 4 animals as a control group. Animals were killed at 2 days, 3 months and 6 months. Feasibility, efficacy and safety were evaluated radiologically, clinically and histologically. RESULTS: Preparation was easy, without risk of catheter clogging or adhesiveness. Embolic delivery was well controlled under subtracted fluoroscopy. Visibility was homogeneous throughout the injection and the material behaved cohesively upon delivery. Best lesion penetration was obtained with the use of proximal microballoon occlusion. Unforeseen over-dilution of the test material by DMSO prefilled in the microballoon hub changed the material properties and caused inadvertent cerebral embolization leading to death in five animals. This phenomenon was avoided by practical measures. The casts produced no beam-hardening artefacts on CT scans. Histology showed excellent biocompatibility. CONCLUSIONS: Embolization with this novel, iodinated, precipitating polymer was feasible and effective. Care should be taken during delivery to avoid over-dilution of the material by prefilled DMSO. The material is promising for embolization of AVMs and hypervascular lesions. KEY POINTS: • The intrinsically opaque precipitating polymer has adequate fluoroscopic visibility • The polymer does not induce shading or beam-hardening artefacts on CT • The novel liquid embolic material does not require lengthy preparation • Lack of implant adherence reduces the risk of entrapment of the delivery catheter.

Absolute Ethanol Embolisation of Mandibular Arteriovenous Malformations Following Direct Percutaneous Puncture and Release of Coils via a Microcatheter.

OBJECTIVE/BACKGROUND: To evaluate the safety, efficacy, and medium-term outcome of a modified technique of ethanol embolisation of mandibular arteriovenous malformations (AVMs) following a direct percutaneous transvenous approach to the release of coils via a microcatheter. METHODS: From January 2012 to July 2014, 18 consecutive patients (mean age 20.9 years [range 10-35 years]) with symptomatic AVMs of the mandible were enrolled. A microcatheter was inserted into the lesion via a direct percutaneous puncture needle. Electrolytically detachable coils and 0.018 mm coils were super-selectively placed to decrease the flow and volume of the arteriovenous fistulas via a microcatheter. Absolute ethanol was injected to obliterate the fistulas. Clinical follow-up was performed in all patients. Therapeutic outcomes were determined by evaluating the degree of devascularisation at follow-up angiography and symptoms and signs. RESULTS: Transvenous release of coils combined with absolute ethanol embolisation were used in all cases. The amount of ethanol used ranged from 5 to 50 mL (mean 25.7 mL) in a single session. Sixteen of 18 patients were cured, and two had partial remission. Follow-up times ranged from 8 to 26 months (medium 15.7 months), and there was no angiographic recurrence of the lesions. Minor complication occurred in five of the 18 patients. There were no major complications. CONCLUSION: Absolute ethanol embolisation following a direct percutaneous transvenous approach to release coils via a microcatheter is a feasible, safe, and highly effective method for the management of mandibular AVMs.

Mandibular AV Malformation: A Rare Cause of Massive Bleeding from Mouth Managed with Multiple Vessel Embolization.

An arteriovenous malformation (AVM) is a site of abnormal connectivity between arteries and veins. Arteriovenous malformations of jaw are extremely rare conditions that can result in disastrous complications, if handled carelessly. Although various treatment modalities have been advocated in the literature, there seems to be no complete consensus on a suitable treatment in these cases. We describe a case of mandibular AVM, who presented with massive bleeding from mouth and each time, embolization of one vessel was done, it recruited new vessel.