Onyx™ Cast Fragmentation After Embolization of Endoleaks.

PURPOSE: Endoleaks are common following endovascular aneurysm repair (EVAR), and the liquid embolic material Onyx has been widely used in their treatment. We report our experience of long-term morphological changes of Onyx casts on surveillance imaging. MATERIALS AND METHODS: We identified 10 patients over 10 years who underwent Onyx embolization in our institution. Morphological changes of Onyx casts were assessed on surveillance radiographs and computed tomography (CT) scans. Relevant outcome data and sequelae were obtained via electronic patient records. RESULTS: Twelve procedures were performed on 10 cases, 9 for type 2, and 1 for a type 1a endoleak. Five cases showed evidence of Onyx fragmentation on follow-up imaging ranging from a single fracture to gross fragmentation with migration of fragments. Of these 5, 3 had achieved primary success but 2 went on to develop recurrence of endoleak. Onyx volume ranged from 4 to 46.5 ml (median 10.5 ml) per patient with larger volumes demonstrating the most marked fragmentation on follow-up. Follow-up ranged from 9 months to 8 years (median 2.25 years). CONCLUSION: To our knowledge, this is the first report of Onyx fragmentation after endoleak embolization. If long-term morphological stability of the Onyx cast is necessary to maintain aneurysm seal, then Onyx may not offer a permanent solution to some patients with post-EVAR endoleaks. Our study cannot ascertain whether the observed changes were the cause or the effect of ongoing aneurysm growth, persistent endoleak, and/or other forces acting on the solidified polymer, but it raises important questions on the use of Onyx in this setting.

Onyx versus coil embolization for the treatment of type II endoleaks.

OBJECTIVE: Little evidence is available supporting the optimal treatment of type II endoleaks associated with aortic sac growth. Previous studies have lacked comparisons between treatment methods and long-term follow-up. The purpose of the present study was to review our center's experience with the treatment of type II endoleaks comparing Onyx (a liquid embolization agent consisting of ethylene vinyl alcohol; Medtronic, Minneapolis, Minn) embolization and coil embolization. METHODS: A retrospective review of prospectively collected data from a vascular surgery database was performed to identify all patients who had undergone embolization of a type II endoleak for aortic sac growth after endovascular aneurysm repair from 2005 to 2018. The Onyx and coil embolization groups were compared using univariate statistics. RESULTS: A total of 58 patients had undergone 77 embolization procedures for type II endoleaks with either Onyx (27 patients; 37 procedures) or coils (31 patients; 40 procedures). The average aneurysm size at embolization was larger in the Onyx group (77.9 ± 15.1 mm) compared with coil embolization (73.4 ± 11.9 mm). The mean follow-up was 57 months for the Onyx group and 74 months for the coil embolization group. Of the 27 patients who had undergone Onyx embolization, 2 (7.4%) had required graft explantation compared with 5 of the 31 patients (16.1%) who had undergone coil embolization (P = .33). The results of the per-patient analysis showed that the coil embolization group had a significantly greater rate of the need for further reintervention compared with the Onyx group (55% vs 19%; P < .01). Clinical success was observed in 13 patients (48%) in the Onyx embolization group compared with 10 patients (32%) in the coil embolization group (P = .04). Two patients in each group had presented with secondary rupture of the aneurysm sac after attempted embolization. CONCLUSIONS: Type II endoleaks associated with sac growth treated with Onyx were less likely to require further reinterventions than were those treated with coil embolization. A trend was found toward a greater need for endovascular aneurysm repair explant after coil embolization. With a high rate of further reintervention and potential for sac rupture, diligent follow-up is required after attempted type II embolization, regardless of the technique used.

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.

Facial palsy after embolization with Squid® 12.

Endovascular procedures with liquid embolic agents such as ethylene-vinyl alcohol (EVOH) copolymers are indicated before surgical treatment of cervical paraganglioma. Consequently, these agents are now available as low viscosity formulations, one of which is Squid 12, which are demonstrating superior vascular penetration. Cases of facial paralysis secondary to embolization of cervical vascular lesions with classic embolic agents have been reported in the English literature, however, this complication has not been described with new generation options such as Squid 12.We describe the case of a 43-year-old patient with a left neck carotid paraganglioma. Embolization was performed under general anaesthesia before surgical excision. In the immediate postoperative period, the patient developed total left facial palsy. Since the imaging tests (Computed Tomography (CT) and Magnetic Resonance Imaging (MRI)) and neurological examination showed no involvement of additional cranial nerves (CN), we hypothesise that the main cause of this complication is ischemia of the vasa nervorum of CN VII secondary to embolization. Almost six months later, the patient continues to present total facial paralysis (Grade VI House-Brackmann facial paralysis scale), and palsy of the left CN X and XII as a complication secondary to surgical resection of the paraganglioma.This case is relevant since it is the first clinical case of permanent facial paralysis secondary to embolization with Squid 12.

A Damp-and-Push Technique for the Copolymer (Onyx) Embolization of Dural Arteriovenous Fistula.

BACKGROUND: Copolymer (Onyx) embolization is an effective treatment for dural arteriovenous fistula (dAVF), however, some dAVFs have multiple, high-flow feeding vessels, resulting in insufficient embolization. For the treatment of such patients, we have developed a novel flow-control technique, the 'damp-and-push technique'. The purpose of this study was to evaluate the technical efficiency and safety of this technique. METHODS: Seven patients who had been diagnosed with intracranial dAVF were treated by transarterial Onyx embolization using the damp-and-push technique between 2016 and 2019. This technique was designed to reduce blood flow to the shunt site using a balloon catheter in the major feeding vessel other than the one injected with Onyx, leading to better Onyx penetration and enabling more controlled embolization of complex dAVFs. Retrospectively collected data were reviewed to assess the occlusion rates and clinical outcomes. RESULTS: The dAVF was at a transverse sinus-sigmoid sinus junction in four patients, in the superior sagittal sinus in two, and in the tentorium in one. Five cases were Cognard type Ⅱb and two cases were Cognard type Ⅳ. All the patients were treated by transarterial Onyx injection via the main feeding vessel, combined with flow reduction in the other main feeding vessel using a balloon catheter. Complete occlusion was achieved in six patients and elimination of cerebral venous reflux was achieved in all the patients. There were no immediate or delayed post-interventional complications. CONCLUSIONS: Transarterial Onyx embolization of dAVF using the damp-and-push technique is safe and yields a high complete occlusion rate.

Elective Embolization of Splenic Artery Aneurysms with an Ethylene Vinyl Alcohol Copolymer Agent (Squid) and Detachable Coils.

PURPOSE: To report the safety and efficacy of the embolization of splenic artery aneurysms (SAAs) with coils plus ethylene vinyl alcohol copolymer (EVOH) agent. MATERIALS AND METHODS: A single-center retrospective study was conducted from 2016 to 2019 to collect SAAs. Twelve asymptomatic patients (mean age, 59 years) with 15 SAAs (mean size, 23.6 mm; size range, 15-40 mm) were treated with embolization. Embolization was performed with EVOH (Squid 8/34) and fibered detachable coils. Transfemoral embolization was performed with a microcatheter to achieve a splenic artery occlusion embolizing the SAA and its efferent and afferent branches. Follow-up was based on color Doppler ultrasound at 24 hours and on computed tomography (CT) angiography at 1 (n = 12) and 6 months (n = 12) after embolization. Mean number of coils and Squid vials used for each patient, major/minor complications, technical success, 30-day clinical success, cases of revascularization/reintervention, and mortality were assessed. Technical success was defined as complete exclusion of the aneurysmal segment and cessation of blood flow into the sac. Clinical success at 1 month was based on the absence of clinical symptoms and the exclusion of aneurysm revascularization on CT angiography. RESULTS: The mean number of coils and Squid vials was 5.75 (standard deviation [SD], 1.58; range, 3-9) and 1.41 (SD, 0.49; range, 1-2), respectively. Both technical and 30-day clinical success were 100%, with no cases of aneurysm revascularization (CT angiography performed in all patients at 1 month and 6 months and in 3 patients at 24 months). No major complications or fatal events were recorded. In terms of minor complications, 2 cases of mild pancreatitis (transient amylases increase) and 1 case of focal splenic ischemia without clinical sequelae were recorded. CONCLUSIONS: Embolization in SAAs using coils plus EVOH was safe and effective without SAA revascularization.

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).

Injection of oral medication into the skin confirmed by infrared spectroscopy.

"Skin popping" refers to the practice of injecting drugs, most commonly heroin, subcutaneously or into granulation tissue. Pharmaceutical tablets meant for oral consumption are modified into solutions for injection. Excipients-inactive substances that serve as vehicles for medication-are often not filtered out before injection and result in abscess formation, granulomatous inflammation, and scarring. Common excipients used in the production of pharmaceutical tablets include starch, microcrystalline cellulose, magnesium stearate, silica, and polyvinylpyrrolidone (PVP). Identification of these exogenous materials is valuable in confirming the diagnosis of skin popping, especially when patients may not be forthcoming about their drug use. We present a case of subcutaneous oral medication injection in which PVP and cellulose were identified by Fourier transform infrared spectroscopy. Considering the variable cutaneous manifestations of injection drug abuse, recognition of histopathologic and chemical characteristics of exogenous material from oral medications is helpful for diagnosis and intervention.

Outcomes of Onyx® Embolization of Type II Endoleaks After Endovascular Repair of Abdominal Aortic Aneurysms.

BACKGROUND: Type II endoleaks (T2ELs) are common following endovascular repair of abdominal aortic aneurysms (EVAR). Embolization with ethylene vinyl alcohol copolymer (Onyx) may present an effective treatment alternative for T2ELs. Due to limited data supporting its use, we sought to analyze outcomes of Onyx embolization for T2ELs. METHODS: Retrospective review of consecutive patients treated for T2ELs utilizing Onyx embolization agent from 2009-2018. All pre- and post-Onyx intervention CT scans were analyzed for diameter and volume changes with 3D reconstruction software. The primary outcomes were change in maximum AAA diameter and volume. Secondary outcomes included additional interventions, rupture, and mortality. A subset analysis was performed with patients with isolated T2ELs (no other types of endoleaks present). RESULTS: We identified 85 patients (73 males, mean age 77.6 ± 7.6 years) who underwent 112 Onyx interventions. Average time to first Onyx intervention after index EVAR was 3.3 ± 2.6 years and average sac growth was 6.3 ± 6.7 mm. Patients underwent mean 1.3 Onyx interventions using a mean of 4.9 ± 4.7 ml for treatment. Three complications occurred (Onyx extravasation, colon ischemia, and access site hematoma). Mean follow-up was 2.5 ± 2.1 years after initial Onyx treatment. At the most recent follow-up, sac diameter stabilization was seen in 47% and reduction >5 mm was seen in 19%. Sac growth of >5 mm was seen in 34% of patients following the first Onyx intervention. In our subset of isolated T2EL, 72% had sac stabilization or reduction >5 mm. Four patients experienced a ruptured aneurysm (3 had active type 1 endoleaks). Rupture-free survival was 95% at 5 years, and overall survival was 54% at 5 years. Notably, increasing Onyx interventions were not associated with sac stabilization or reduction (OR 0.6, P = 0.1). On multivariable analysis, AAA sac diameter stabilization or reduction was independently associated with BMI >30 kg/m2 (OR 4.2, P = 0.01) and having only 1 Onyx intervention (OR 3.8, P = 0.02). CONCLUSIONS: Onyx for embolization of T2ELs resulted in AAA sac diameter stabilization or reduction in 66% of patients, and up to 72% in isolated T2ELs. Further, increasing Onyx interventions were not associated with either aneurysm sac stabilization or reduction. Given its similar outcomes to other embolization strategies in the literature, Onyx embolization for management of T2ELs needs to be judiciously considered, particularly for T2ELs persisting after an initial Onyx embolization intervention.

Teflon™ or Ivalon®: a scoping review of implants used in microvascular decompression for trigeminal neuralgia.

BACKGROUND: Trigeminal neuralgia (TN) is characterized by jolts of pain along the distribution of the trigeminal nerve. If patients fail conservative management, microvascular decompression (MVD) is the next step in treatment. MVD is largely done by placing implant pads between the nerve and compressing vessels. We conducted a literature review to assess effectiveness and safety of Teflon™ and Ivalon® sponges for treatment of TN with MVD. METHODS: In January 2019, PubMed was searched for manuscripts published in English using permutations of "Microvascular decompression", "Teflon", "Ivalon", "Granuloma", "Polytetrafluoroethylene", "Trigeminal Neuralgia", and "Exploration". Success and relapse rates, causes of relapse, and complication rates were analyzed. We analyzed for relationships with ANCOVA at an alpha threshold of .05. RESULTS: Thirty-six studies representing 4273 patients fit inclusion criteria. Twenty-five dealt with initial MVD, 12 with re-do MVD. Initial MVD initial success rates were 85% in patients receiving Teflon™ (57-100%*) and 91% in patients receiving Ivalon® (79-100%*). Recurrence rates were 12% in Teflon™ patients (0*-30%) and 9.1% in Ivalon® patients (0*-19%). In patients with relapses, implants were the cause in 49% of Teflon™ patients (0*-100%*) and 50% of Ivalon® patients (0*-100%*). Complication rates for patients receiving Teflon™ were 12% (0*-34%) and 19% for patients receiving Ivalon® (0*-40%). CONCLUSION: Teflon™ and Ivalon® are two materials used in MVD for TN. It is an effective treatment with long-term symptom relief and recurrence rates of 1-5% each year. Ivalon® has been used less than Teflon™ though is associated with similar success rates and similar complication rates.

Transrenal Ureteral Occlusion for Palliation of Refractory Urine Leaks Using Vascular Plugs and Liquid Ethylene Vinyl Alcohol.

PURPOSE: To describe outcomes of transrenal embolization with vascular plugs and ethylene vinyl alcohol (EVOH) in a case series of patients with refractory urinary leak or fistula. MATERIALS AND METHODS: Fifteen ureteral occlusions performed over 53 months in 9 consecutive patients (56% female; mean age 61 y; range, 45-80 y) were reviewed retrospectively. The main indication was palliation for refractory fistula or leak in the setting of malignancy not responding to urine diversion by percutaneous nephrostomy tube or nephroureteral stent. Transrenal ureteral occlusion was performed using EVOH injected between vascular plugs placed distal and proximal to the leak or fistula. RESULTS: Technical success was 100%. Considerable reduction of urine leak or symptoms (clinical success) was achieved in 64% of ureters after mean follow-up of 105 days (range, 0-632 d). Complete ureteral occlusion on follow-up anterograde nephrostogram (imaging success) was achieved in 60% of ureters after mean follow-up of 139 days (range, 0-643 d). One patient with distal ureterovesical junction-perineal fistula had continued leak despite complete proximal occlusion of ureter owing to retrograde urine reflux from the bladder and was treated with endoscopic injection of intramural calcium hydroxyapatite to the ureteral segment distal to the fistula. Three ureters (33%) in 2 patients with vesicovaginal fistula had recanalization, requiring additional proximal embolization, yielding secondary success rates of 91% (clinical) and 90% (imaging) per ureter. One minor urinary tract infection and no major complications occurred. CONCLUSIONS: Transrenal anterograde ureteral occlusion using EVOH between vascular plugs could be considered a relatively safe and potentially valuable treatment option for refractory ureteral fistulae.

Vagal Nerve Palsy After Transarterial Embolization of Transverse-Sigmoid Dural Arteriovenous Fistula Using Onyx.

OBJECTIVE: We report a case of a 70-year-old man who developed a transverse-sigmoid dural arteriovenous fistula (TS-DAVF) that was successfully treated by transarterial embolization (TAE) with Onyx. CASE PRESENTATION: The patient presented with sudden and progressive disturbance of consciousness and left hemiparesis. Magnetic resonance imaging (MRI) revealed venous infarction and hemorrhagic changes with brain swelling in the right parietal lobe. Angiography revealed a right TS-DAVF and multiple occlusions with retrograde leptomeningeal venous drainage into the cortical veins. The TS-DAVF was graded as Borden type III and Cognard type IIa+b. Because of its progressive clinical nature and wide distribution of DAVF in the occluded sinus wall, he underwent emergent TAE with liquid embolic materials including n-butyl cyanoacrylate and Onyx under informed consent by his family. Complete obliteration of the TS-DAVF was achieved, leading to a marked amelioration of symptoms, and MRI after treatment confirmed a decrease in the brain swelling. However, he suffered transient dysphagia due to right vagal nerve palsy caused by occlusion of vasa nervorum of ascending pharyngeal artery. He returned home 5 months later with a modified Rankin Scale of 1. CONCLUSIONS: TAE with Onyx appears to be effective for aggressive TS-DAVF with a widely distributed shunt. However, the blood supply to the cranial nerves and potentially dangerous anastomoses between the external-internal carotid artery and vertebral artery should be taken into account to avoid serious complications.

Septal reduction therapy using nonalcohol agent in hypertrophic obstructive cardiomyopathy: Single center experience.

AIMS: Percutaneous septal reduction therapy by either alcohol or nonalcohol agents is an alternative approach to surgery in drug-refractory symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM). Nonalcohol agents have some advantages and disadvantages over alcohol during the procedure. Nowadays, a novel non-alcohol agent, named as Ethylene-vinyl alcohol (EVOH) copolymer (Onyx® and Squid® ), is used during septal ablation. Thus, in this study, we aimed to evaluate both acute and long-term efficacy and safety profile of EVOH during septal ablation in HOCM. METHODS AND RESULTS: A total of 25 patients (52% female; mean age: 55.8 ± 17.1 years) with symptomatic HOCM were enrolled in the study. All subjects underwent clinical and laboratory assessment before and after the procedure. Peak left ventricular outflow tract (LVOT) gradient was significantly reduced just after the procedure (68 vs. 20 mmHg; P < 0.001). Peak serum creatine kinase-myocardial band and troponin I levels were 112 (35-282) ng/ml and 11 (4-93) ng/ml. EVOH embolization to diagonal artery was observed in 1 patient (4%) and the complete atrioventricular block was noted in 2 (8%) patients. During the 12-month follow-up, there was no mortality. There was a significant improvement in New York Heart Association functional class of the subjects P < 0.001). Both interventricular septum thickness and LVOT gradient showed a significant reduction during follow-up (P < 0.05). However, there was no reduction in the LVOT gradient of 3 patients (12%). CONCLUSIONS: In conclusion, our small-sized preliminary study results showed that septal reduction therapy using EVOH is an effective alternative option in reducing symptoms and LVOT gradient in HOCM.

Transabdominal Direct Sac Puncture Embolization of Type II Endoleaks after Endovascular Abdominal Aortic Aneurysm Repair.

PURPOSE: To determine the efficacy and safety of transabdominal direct sac puncture embolization of type II endoleaks after endovascular abdominal aortic aneurysm repair (EVAR). MATERIALS AND METHODS: This retrospective review included 30 patients (4 women, 26 men; mean age = 79.1 years) who underwent 33 transabdominal direct sac puncture embolization procedures for type II endoleaks after EVAR. Embolization agents included cyanoacrylate glue only (45.5%), glue/coils (36.4%), and Onyx with or without glue/coils (18.1%). Technical success was defined as complete endoleak embolization on intraprocedural fluoroscopy. The primary outcome was freedom of aneurysm growth, which was defined as ≤ 5% aneurysm sac volume change on follow-up computed tomography (CT) imaging or ≤ 5 mm aneurysm sac diameter change on ultrasound without definite endoflow. Aneurysm sac volumes before and after embolization were manually segmented from CT images. The procedural complication rate was calculated. RESULTS: Technical success was achieved in 97% of patients (29/30). Follow-up imaging was available in 27 patients (25 CT; 2 ultrasound), and mean imaging follow-up duration was 15.5 months. Freedom of aneurysm growth was achieved in 85.2% of patients (23/27) after 1 or more embolization procedures. Median fluoroscopic and procedure times were 11.3 minutes and 90 minutes, respectively. The complication rate was 9.1% (3/33) and included 1 case of nontarget embolization with transient neuropraxia and 2 self-limiting rectus sheath hematomas relating to the percutaneous puncture site. No aneurysm-related mortality occurred during the follow-up period. CONCLUSIONS: Percutaneous transabdominal embolization is a safe and efficacious treatment for type II endoleak, with a short procedure time.

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.

Early and midterm outcomes after transcatheter embolization of type I endoleaks in 25 patients.

OBJECTIVE: This study reports the technical success and follow-up results of transcatheter embolization of type I endoleak (ELI) in 25 patients after endovascular aortic repair (EVAR). METHODS: Twenty-five patients with ELI (20 men, five women; mean age 80 years; range, 64-96 years) underwent embolization of abdominal ELI (23 proximal, 2 distal endoleaks) after EVAR. All patients were unsuitable for standard endovascular methods for treatment of ELI. The average aneurysm sac size before embolization was 8.2 cm (range, 5.3-12.9 cm). The average time between EVAR and endoleak diagnosis was 685 days (range, 1-4220 days) and from endoleak diagnosis to embolization was 27 days (range, 2-94 days). Onyx (ev3 Endovascular, Inc, Plymouth, Minn) alone or with detachable coils was used for embolization. RESULTS: A total of 27 embolization procedures were performed, with two patients having undergone a repeat procedure. Onyx alone was used in 16 cases and Onyx and coils were used in 11. Immediate technical success with complete isolation of the endoleak on completion angiography was achieved in all procedures. Six procedural complications occurred: three puncture site hematomas and three cases of non-target Onyx embolization. None of the complications had long term sequelae. During the follow-up period (average, 311 days; range, 1-1357 days), seven patients (28%) developed endoleak recurrence, and two underwent a second embolization procedure. Of these, one has had no further endoleak recurrence, but the other developed a recurrent endoleak and died of sac rupture. Two of the other five cases of endoleak recurrence were successfully managed by other procedures, one had a persistent endoleak despite aortic cuff placement, and the other two were deemed unsuitable for further intervention. Three of the four patients with persistent endoleaks died of sac rupture. At the average follow-up time of 311 days, freedom from endoleak recurrence was 80%, and freedom from sac growth was 85%. CONCLUSIONS: Transcatheter embolization of ELI offers a safe, feasible, and sustainable treatment option for patients who are unsuitable for standard methods of ELI treatment. Additional coil embolization before Onyx injection may result in better outcome.

Promoting False-Lumen Thrombosis after Thoracic Endovascular Aneurysm Repair in Type B Aortic Dissection by Selectively Excluding False-Lumen Distal Entry Tears.

PURPOSE: To evaluate the efficacy and clinical outcomes of ancillary endovascular procedures in promoting false-lumen (FL) thrombosis (FLT) and preventing aortic expansion in patients after thoracic endografting for type B dissections. MATERIALS AND METHODS: This retrospective review included 15 patients (12 men and 3 women; mean age, 59.6 y). Mean aortic diameter at the time of ancillary treatment was 47.4 mm. Different techniques were used as single procedures or sequentially: covered stent occlusion of detached visceral artery entry tears, occlusion of single entry tears with vascular plugs, or aortic endograft occlusion of multiple FL entry tears. FL embolization with ethylene vinyl alcohol copolymer was performed when selective occlusion was considered insufficient to close distal entry tears. Apart from endovascular aneurysm repair, all procedures were performed percutaneously under local anesthesia. If FL diameter increase persisted after 6-month follow-up computed tomographic (CT) angiography, another intervention was planned; otherwise, yearly follow-up was performed. RESULTS: Mean clinical follow-up duration was 43.8 months (range, 8 d to 86.8 mo), with no in-hospital mortality. Estimated overall survival rates were 93.3%, 86.6%, and 77% at 12, 24, and 48 months, respectively. Three late deaths occurred, one of which was dissection-related at 40 months. Eight surviving patients (53%) had total FLT and 3 had partial FLT with stable aortic diameter on follow-up CT angiography. FL diameter increased in one patient, requiring further intervention. CONCLUSIONS: Selective exclusion of new distal entry tears remaining after thoracic endovascular aneurysm repair can stabilize abdominal aortic expansion and promote FLT.

Embolization of Onyx Causing Acute Limb Ischemia.

We present the case of a patient with a refractory type II endoleak treated with translumbar Onyx with passage of the Onyx material into the endograft and subsequent embolization to the infrainguinal vasculature. This report represents a new complication of Onyx embolization that, to our knowledge, has not previously been described in the literature.

Long-term results of intra-arterial onyx injection for type II endoleaks following endovascular aneurysm repair.

Purpose The aim of this paper is to report our experience of type II endoleak treatment after endovascular aneurysm repair with intra-arterial injection of the embolizing liquid material, Onyx liquid embolic system. Methods From 2005 to 2012, we performed a retrospective review of 600 patients, who underwent endovascular repair of an abdominal aortic aneurysm. During this period, 18 patients were treated with Onyx for type II endoleaks. Principal findings The source of the endoleak was the internal iliac artery in seven cases, inferior mesenteric artery in seven cases and lumbar arteries in four cases. Immediate technical success was achieved in all patients and no endoleak from the treated vessel recurred. During a mean follow-up of 19 months, no major morbidity or mortality occurred, and one-year survival was 100%. Conclusions Treatment of type II endoleaks with Onyx is safe and effective over a significant time period.

Endovascular Treatment of Noncavernous Dural Arteriovenous Fistulas: Analysis of Outcomes with and without Ethylene Vinyl Alcohol.

OBJECTIVE: Noncavernous dural arteriovenous fistulas (DAVFs) are uncommon lesions that can be treated from an endovascular approach using various embolic materials. The purpose of this study was to evaluate our outcomes for endovascular treatment of DAVFs with and without the use of ethylene vinyl alcohol (EVOH). METHODS: We performed a retrospective analysis of 65 patients treated for DAVF at our institution from January 1995 to May 2015. Lesions were classified as aggressive or benign, based on angiography according to Cognard classification. Demographic data, medical comorbidities, presenting symptoms, treatment modality, treatment outcomes, and complications were evaluated for each group. Primary outcome was defined as angiographic occlusion for an aggressive DAVF, and resolution of clinical symptoms for a benign DAVF. RESULTS: The primary outcome was met in 47 (82.5%) of 57 cases with endovascular therapy alone; 23 (69.7%) of 33 aggressive fistulas; and 24 (100.0%) of 24 benign fistulas. There was a 5% overall complication rate. The primary outcome was achieved via endovascular approach in 80.0% (24 of 30) of cases with EVOH, and 85.2% (23 of 27) of cases without EVOH (P = .73). There was a 6% complication rate for procedures using EVOH versus 3% for cases without EVOH (P = 1.00), a 13% clinical recurrence rate for cases using EVOH compared to .0% when EVOH was not used (P = .24), and no angiographic recurrences in either group (P = 1). There were no procedure-related mortalities. CONCLUSIONS: Endovascular treatment of DAVFs has a high success rate and low complication rate. Our experience demonstrated no difference in outcomes between lesions treated with EVOH and those treated without EVOH.