Determination of the Optimal Ratio and the Relationship Between Viscosity and Adhesion of n-Butyl Cyanoacrylate-Lipiodol-Iopamidol for Balloon-Assisted Embolization of Wide-Neck Aneurysms in Swine.

PURPOSE: To determine the optimal ratio of n-butyl cyanoacrylate-Lipiodol-iopamidol (NLI) for balloon-assisted embolization of wide-neck aneurysms in swine. MATERIALS AND METHODS: Sixteen NLI mixtures were prepared for in vitro studies. The viscosity of each mixture was measured for 30 min. We evaluated whether the mixtures could be injected through a microcatheter and whether they adhered to the microcatheter. In vivo, 15 wide-neck aneurysms were created on the arteries in 4 female swine. Under balloon occlusion, 7 aneurysms were embolized with NLI141 (NBCA:Lipidol:iopamidol = 1:4:1) and 8 were embolized with NLI231. We performed angiography to evaluate adhesion of NLI to the balloons or microcatheters and NLI migration. RESULTS: In vitro, the iopamidol content needed to comprise at least 1/6 of the mixture in order for NLI to be non-adhesive with increased viscosity. NLI could not be injected through a microcatheter if the iopamidol content exceeded 1/6 of the mixture. Only NLI141 and NLI231 did not adhere to the microcatheter with increased viscosity, and could be injected through a microcatheter. In vivo, neither NLI mixture adhered to the balloons or microcatheters. The migration of NLI was observed in 6 of 7 aneurysms embolized with NLI141 and in none of 8 aneurysms embolized with NLI231. CONCLUSION: Our in vitro study revealed that the ratios of NLI that were non-adhesive and could be injected through a microcatheter were 1:4:1 and 2:3:1. The optimal ratio of NLI for balloon-assisted embolization of wide-neck aneurysms in swine was considered to be 2:3:1.

Feasibility and Safety of n-Butyl Cyanoacrylate-Lipiodol-Iopamidol as an Alternative Liquid Embolic Material.

PURPOSE: To evaluate the feasibility and safety of n-butyl cyanoacrylate (NBCA)-Lipiodol-Iopamidol (NLI) as a liquid embolic material. MATERIALS AND METHODS: In vitro, the ratio of NLI components was adjusted and the configuration of the mixtures was assessed visually in saline. In vivo, 14 wide-necked aneurysms were created on the common carotid and external iliac arteries of four female swine. Under balloon occlusion, 12 aneurysms were embolized with NLI prepared at a NBCA-Lipidol-Iopamidol ratio of 2:3:1 (NLI231), and two were embolized with NBCA-Lipiodol (NL) prepared at a NBCA-Lipiodol ratio of 1:2 (NL12) as a trial group. We performed angiography to evaluate the effectiveness of embolization and adhesion of the embolic material to the balloons or microcatheters. RESULTS: In vitro, NLI231 (33% NBCA) was considered to be the optimal ratio for aneurysm embolization based on its configuration and stability. In vivo, embolization using NLI231 was successful and no adhesion between the embolic material and the balloons or microcatheters was observed in all 12 aneurysms. Embolization with NL12 was impossible in the other two aneurysms due to leakage and adhesion of NL. CONCLUSION: The configuration of NLI changed at each ratio. NLI231 is a feasible and safe liquid embolic material for balloon-assisted embolization of wide-necked aneurysms in swine.

Balloon-Assisted Embolization of Wide-Neck Aneurysms Using a Mixture of n-Butyl Cyanoacrylate, Lipiodol, and Ethanol in Swine: A Comparison of Four n-Butyl Cyanoacrylate Concentrations.

PURPOSE: To determine the optimal ratio of n-butyl cyanoacrylate (NBCA)-Lipiodol-ethanol (NLE) mixture for balloon-assisted embolization of wide-neck aneurysms. MATERIALS AND METHODS: We created 32 wide-neck aneurysms on both the common carotid arteries and external iliac arteries in eight female swine. Eight aneurysms were randomly assigned to four groups. Under balloon occlusion, the aneurysms were packed using NLE at one of four ratios of NLE: 2:2:1 (NLE221; 40%NBCA); 3:6:1 (NLE361; 30%NBCA); 2:7:1 (NLE271; 20%NBCA); and 1:5:1 (NLE151; 14.3%NBCA). We performed angiography before and after embolization to assess the aneurysms, and we compared adhesion between NLE and the balloon and assessed NLE migration. Three days after embolization, the aneurysms were removed for histopathologic evaluation. RESULTS: Embolization was performed in 27 aneurysms. Adhesion between NLE and the balloon was not observed in any group. NLE migration was found in 0/7 aneurysms in the NLE221 group, 0/6 in the NLE361 group, 5/6 in the NLE271 group, and 7/8 in the NLE151 group. NLE migration was significantly lower in the NLE221 group than in the NLE271 and NLE151 groups (P = 0.0047 and 0.0014, respectively) and was significantly lower in the NLE361 group than in the NLE271 and NLE151 groups (P = 0.0152 and 0.0047, respectively). Media necrosis of the arterial wall close to the aneurysms was observed in all groups. CONCLUSION: NLE with an NBCA concentration of ≥ 30% is a safe and feasible embolic material for balloon-assisted embolization of wide-neck aneurysms in swine in the short term up to 3 days after embolization.

Multiple Enlarged Aneurysms in Primary Racemose Hemangioma of the Bronchial Artery: Successful Prophylactic Transcatheter Arterial Embolization Using N-butyl-2-cyanoacrylate and Coils.

An asymptomatic 48-year-old man presented with multiple aneurysms in a primary racemose hemangioma of the right bronchial artery. Bronchial arteriography revealed a tortuous artery with four fusiform aneurysms of varying sizes and aneurysmal dilatation with marked thrombus formation in the long segment of the distal portion. Because the tip of catheter could not pass beyond the aneurysmal dilatation, we performed balloon-occluded embolization using a mixture of N-butyl-2-cyanoacrylate (NBCA) and iodized oil. For four other aneurysms, we performed embolization using a coil alone or with NBCA. After 6 months, right bronchial arteriography revealed no enhancement of the aneurysms. Despite the rarity of this procedure, embolization with NBCA is a good option for bronchial artery aneurysm embolization.

MR Coagulation: A Novel Minimally Invasive Approach to Aneurysm Repair.

PURPOSE: To demonstrate a proof of concept of magnetic resonance (MR) coagulation, in which MR imaging scanner-induced radiofrequency (RF) heating at the end of an intracatheter long wire heats and coagulates a protein solution to effect a vascular repair by embolization. MATERIALS AND METHODS: MR coagulation was simulated by finite-element modeling of electromagnetic fields and specific absorption rate (SAR) in a phantom. A glass phantom consisting of a spherical cavity joined to the side of a tube was incorporated into a flow system to simulate an aneurysm and flowing blood with velocities of 0-1.7 mL/s. A double-lumen catheter containing the wire and fiberoptic temperature sensor in 1 lumen was passed through the flow system into the aneurysm, and 9 cm3 of protein solution was injected into the aneurysm through the second lumen. The distal end of the wire was laid on the patient table as an antenna to couple RF from the body coil or was connected to a separate tuned RF pickup coil. A high RF duty-cycle turbo spin-echo pulse sequence excited the wire such that RF energy deposited at the tip of the wire coagulated the protein solution, embolizing the aneurysm. RESULTS: The protein coagulation temperature of 60°C was reached in the aneurysm in ∼12 seconds, yielding a coagulated mass that largely filled the aneurysm. The heating rate was controlled by adjusting pulse-sequence parameters. CONCLUSIONS: MR coagulation has the potential to embolize vascular defects by coagulating a protein solution delivered by catheter using MR imaging scanner-induced RF heating of an intracatheter wire.

[TREATMENT DILEMMAS IN BEHÇET'S SYNDROME].

Behçet's disease is an inflammatory systemic disorder, characterized by a relapsing and remitting course, it manifests with oral and genital ulcerations, skin lesions, uveitis, vasculitis, central nervous system and gastrointestinal involvement. The main histopathological finding is widespread vasculitis of the arteries and veins. Therapy is variable and depends largely on the severity of the disease and organ involvement. There is common practice to treat with anticoagulation in patients suffering from vessel thrombosis, but there are no control trials to support this tendency. Anticoagulation treatment can cause major bleeding events in patients suffering from aneurysms. In this case report we describe a treatment dilemma in a patient suffering from deep vein thrombosis and pulmonary aneurysms.

Successful treatment of central retinal artery thromboembolism with ocular massage and intravenous acetazolamide.

A 67-year-old woman presented with left-sided headache and blurred vision, worse during hypertensive episodes. CT angiography showed a 4 mm left internal carotid artery (ICA) aneurysm incorporating the ophthalmic artery. She passed a test balloon occlusion, so the aneurysm was coil occluded, without immediate complication. Four days postprocedure she experienced sudden loss of vision in the left eye and funduscopy showed central retinal artery occlusion secondary to emboli from the coiled aneurysm. She was treated promptly with intravenous acetazolamide and ocular massage and regained full visual acuity. Thromboembolism to the eye during or after neurointerventional treatment is a relatively rare but devastating complication. This report demonstrates the effectiveness of combined intravenous acetazolamide and ocular massage in dealing with this complication when delivered promptly.

Basic study of a mixture of N-butyl cyanoacrylate, ethanol, and lipiodol as a new embolic material.

PURPOSE: To clarify the configuration change of N-butyl cyanoacrylate (NBCA) polymerization with increasing proportion of ethanol, the properties of a mixture of NBCA with lipiodol plus ethanol (NLE), and the feasibility of use of NLE for aneurysm packing in a swine model. MATERIALS AND METHODS: The polymerization configuration of NLE was explored using ratios of 1-4 parts NBCA and 1-3 parts ethanol per 1 part of lipiodol; a 1:1 ratio of NBCA to lipiodol (NLE110) was used as a control. The distance that NLE migrated into saline flowing in a tube was measured. A carotid artery aneurysm was created in each of 18 swine. Aneurysmal packing with three configurations--NLE110, NLE at a ratio of 1:1:2 (NLE112), and NLE at a ratio of 1:1:3 (NLE113)--was attempted in six swine for each configuration. RESULTS: Regardless of NBCA composition, medium-sized droplets, a single large droplet, and a noodle-shaped extrusion were observed in NLE with lipiodol versus ethanol ratios of 1:1, 1:2, and 1:3. NLE110 migrated as viscous fluid to 190 cm from the injection site, whereas NLE112 migrated for 81 cm ± 11 and NLE113 migrated for 74 cm ± 9. Instant outflow of NLE110 from the six aneurysms caused occlusion of the parent artery, with adhesion to the microcatheter. Packing was achieved with minimal adhesion for all six of the aneurysms packed with NLE112 or with NLE113. CONCLUSIONS: With high ratios of ethanol, the NLE polymerization configuration acquired solid-like properties with potent occlusive ability and negligible adhesion to the microcatheter, suggesting its feasibility for packing of aneurysms.

Assessment of EmboGel--a selectively dissolvable radiopaque hydrogel for embolic applications.

PURPOSE: To evaluate the embolic properties of an alginate-based embolic biomaterial (EmboGel) and its solvent (EmboClear) in treatment of aneurysms. MATERIALS AND METHODS: EmboGel is a mixture of iohexol and alginate that polymerizes into a hydrocoil when delivered through a coaxial catheter with a distal mixing tip, exposing alginate to a calcium chloride solution. In contrast to previously reported embolic agents, EmboGel can be selectively dissolved by EmboClear, a mixture of the enzyme alginate lyase and ethylenediaminetetraacetic acid (EDTA). The embolic and contrast properties of EmboGel were assessed in in vitro models of saccular aneurysm and an aortic aneurysm endoleak. The dissolvability of EmboGel with EmboClear was assessed further after endovascular delivery in the New Zealand white rabbit in the native aortoiliofemoral territory, a created saccular aneurysm, and the native carotid arteries. RESULTS: EmboGel effectively filled aneurysm cavities in the case of stent excluded saccular and fusiform aneurysms. EmboGel was readily dissolved by EmboClear in vitro and after in vivo embolization. When the distal abdominal aorta and pelvic arteries were occluded with EmboGel, within 1 minute of EmboClear infusion, patency of the aorta and most of the pelvic circulation was regained as noted by angiography. Embolization in the subclavian artery and numerous distal branches was rapidly dissolved by EmboClear. Finally, the carotid artery occluded with EmboGel regained patency after administration of EmboClear. CONCLUSIONS: EmboGel is a dissolvable alginate-based biomaterial that can be used for numerous embolic applications. EmboGel can be selectively dissolved with EmboClear, a solution of alginate lyase and EDTA.

Endovascular therapy of bronchial artery aneurysm: five cases with six aneurysms.

The objective of this study was to investigate the effect of transcatheter arterial embolization (TAE) with N-butyl-2-cyanoacrylate (NBCA)-Lipiodol mixture in patients with bronchial artery aneurysm (BAA). From January 2005 to January 2010, five patients presenting hemoptysis with six BAAs were treated with NBCA-Lipiodol mixture, including intra-aneurysm embolization (IAE) in one patient. Adjuvant embolization with spherical polyvinyl alcohol (PVA) embolic microparticles or NBCA was first performed to embolize the distal engorged bronchiectatic arteries. Bronchial arterial angiography showed six BAAs (four in the right lobe and two in the left lobe) and some engorged, tortuous bronchial arteries. TAE through microcatheter was successful in all cases. Postembolization angiogram demonstrated the NBCA cast and total occlusion of BAAs and bronchiectatic engorged vessels. After these procedures, hemoptysis completely disappeared in all patients. Follow-up computed tomography (CT) scan was performed at an average of 3 months (range 2 to 6), which showed no enhancement of BAAs and accumulation of NBCA. TAE is a minimally invasive, effective, and reliable approach for treatment for patients with BAA. NBCA-Lipiodol mixture provides a good choice for treatment of BAA, especially when catheterization of the efferent branches is impossible.

Pancreatitis after transcatheter embolization of a splenic aneurysm.

A 52-year-old woman was treated for a splenic aneurysm that was found on abdominal computed tomography (CT) during a preoperative assessment for rectal cancer. The aneurysm was embolized using the "double coil-delivered microcatheter technique," and 4 ml of a mixture of N-butyl 2-cyanoacrylate (NBCA) and iodized oil (Lipiodol) (NBCA/Lipiodol = 1.0: 2.5) were injected into the aneurysm. The patient complained of left upper quadrant abdominal pain immediately after the procedure. A blood test 2 days after the procedure showed an increased white blood cell count (13,100/microl), C-reactive protein (13.36 mg/dl), and pancreatic amylase (428 U/l). Abdominal CT scan showed a huge cystic lesion at the pancreatic tail, in the center of which was a highly enhanced area due to accumulated NBCA-Lipiodol. Postembolization pancreatitis was diagnosed, and treatment with fasting and a drip infusion of nafamostat mesilate was started. The patient's abdominal pain became less severe within 3 days, and the pancreatic enzyme level had normalized 14 days after treatment. On CT, the cystic lesion at the pancreatic tail was smaller 20 days after the procedure, and it had disappeared completely 75 days after the procedure.

Comparison of photodynamic therapy to transpupillary thermotherapy for polypoidal choroidal vasculopathy.

PURPOSE: To compare the therapeutic efficacy of photodynamic therapy (PDT) to that of transpupillary thermotherapy (TTT) for polypoidal choroidal vasculopathy (PCV). METHODS: PDT or TTT was performed on 46 eyes of 46 patients with PCV; 19 eyes were treated with TTT (TTT group) and 27 eyes with PDT (PDT group). PCV was diagnosed by fundus examination, fluorescein angiography (FA) , and indocyanine green angiography (ICGA) . The best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR) units and OCT-determined foveal thickness were evaluated before and after treatment. For statistical analyses, the Student's t-test and chi(2) test were used. RESULTS: The number of treatments during the 12-month follow-up period was significantly higher in the TTT group (1.7 times) than in the PDT group (1.3 times; P=0.0134). The difference in the BCVA between the TTT and PDT groups at the baseline was not significant (P=0.3150), but the BCVA in the PDT group was significantly better than that in the TTT group at 3, 6, and 12 months after treatment (P=0.0093, P=0.0074, P=0.0006, respectively). The foveal thickness decreased markedly at 6 months after treatment in the PDT group (P<0.0001) but not significantly in the TTT group (P=0.8982). A vitreous haemorrhage was observed after treatment in two eyes in the TTT group. CONCLUSIONS: BCVA was significantly better and the fovea was significantly thinner in the PDT group than in the TTT group after treatment. Thus, PDT may be more effective than TTT for the treatment of eyes with PCV.

Endovascular treatment of visceral aneurysms associated with pancreatitis and a suggested classification with therapeutic implications.

PURPOSE: To describe a 10-year experience of endovascular and percutaneous treatment of aneurysms and pseudoaneurysms complicating pancreatitis, and to analyze this experience and propose a classification based on computed tomography (CT) and angiographic findings that has therapeutic implications. This may reduce the rate of recurrent bleeding after surgery or endovascular treatment. MATERIALS AND METHODS: Twenty-three patients with aneurysms or pseudoaneurysms associated with acute pancreatitis were treated by endovascular or percutaneous methods. All underwent CT and angiography. The early development of a simple classification based on the CT and angiographic findings was used to guide treatment decisions. In accordance with this classification, 19 patients were treated by primary coil embolization and four were treated by primary percutaneous thrombin injection. RESULTS: Among the 19 patients treated by primary coil embolization, there were two early recurrences of the pseudoaneurysm. All four patients treated by percutaneous thrombin injection exhibited late recurrences and were successfully treated by percutaneous thrombin injections. Twenty-one patients (91.3%) were alive at 6 months. CONCLUSIONS: Endovascular and percutaneous treatment of aneurysms and pseudoaneurysms complicating pancreatitis is safe and effective and is associated with good outcomes, but careful follow-up is necessary. The decision of which treatment option is most appropriate can be made in accordance with a classification based on CT and angiographic appearance.

Bronchial artery aneurysm embolization with NBCA.

We present a case of asymptomatic bronchial artery aneurysm that formed a fistula with part of the pulmonary artery (there was no definite fistula with the pulmonary vein). We were able to catheterize the feeding vessel but could not reach the aneurysm. We therefore injected a mixture of N-butyl-2-cyanoacrylate (NBCA; Histoacryl, B. Braun, Melsungen, Germany) and iodized oil (Lipiodol; Guerbet, Aulnay-sous-Bois, France) from the feeding vessel. The fistula, aneurysm, and feeding vessel were almost totally occluded. After embolization, the patient coughed a little; there were no other definite side effects or complications. One and 3 months later, on chest CT, the aneurysm was almost completely occupied with hyperattenuating NBCA-Lipiodol embolization. NBCA is a liquid embolization material whose time to coagulation after injection can be controlled by diluting it with Lipiodol. It is therefore possible to embolize an aneurysm, feeding vessels, and efferent vessels (in our case, it was a fistula) by using an NBCA-Lipiodol mixture of an appropriate concentration, regardless of whether the catheter can reach the aneurysm or not.

Treatment of aneurysms with wires and electricity: a historical overview.

Endovascular treatment of aneurysms has only recently become an accepted therapeutic modality. Nonetheless, treatment of aneurysms with the aid of various foreign bodies such as needle and wire insertion with or without electrical current has been reported since the first half of the 19th century. In 1832 Phillips induced clot formation in the femoral and carotid arteries of dogs by leaving needles in the arteries for variable lengths of time. Simultaneously, in France, Velpeau had proposed using "l'acupuncture des arteres dans le traitement des anevrismes." Later, Phillips and Pelrequin connected the offending needles to a source of electrical current in an attempt to increase thrombus formation and aneurysm occlusion. Subsequently, Moore introduced the concept of packing the aneurysm with wire inserted through a needle transfixed to the vessel wall. To this method, Corradi added electrical current. Widely known as the Moore-Corradi technique, it was used in ensuing years with variable success. The early phase of endovascular aneurysm treatment culminated when Blakemore and Moore treated a case of symptomatic cavernous sinus aneurysm by passing wire through the patient's orbit. These pioneering cases combined with technological advances in the diagnosis of intracranial aneurysms paved the way for further refinements in coil embolization of aneurysms.

[Re-evaluation of an embolic material for aneurysm cellulose acetate polymer].

OBJECTIVE: To re-evaluate the safety, effect, and pathological reactions of cellulose acetate polymer (CAP). METHODS: 30 right carotid arteries of rats were embolized and got two embolized vessels for histological study in each of the seven stages within four months. Fifteen canine aneurysmal models were created by transplantation of venous pouches. Twelve of them were occluded with CAP. Digital Subtraction Angiography (DSA) follow-ups of occluded aneurysmal models were carried out 1, 2 and 8 weeks after occlusion. One animal was sacrificed randomly at each stage for pathological study. RESULTS: Only five of the 12 aneurysmal models were completely or partially occluded within the patency of parent arteries within two months of observation after embolization with CAP. Stenosis of one branch of aneurysmal parent artery was occurred. The residual cavity of one partially occluded model artery was enlarged. Two models ruptured on four and five days after embolization. Three embolized models and their parent arteries were all occluded. PATHOLOGICAL FINDINGS: acute pathological reaction occurred within vessels embolized with CAP. Endothelial cell and basal membrane were damaged and vanished. Elastic lamina was exposed to arterial lumen and attached by thrombus layer. Fibrous cells and smooth muscle cells showed obvious degeneration. CAP and thrombus were gradually organized in two months after thrombosis. The orifices of aneurysmal models were covered with newly developed fibrous tissue and endothelial cells in two months after thrombosis. CONCLUSIONS: We think that acute chemical erosive effect of CAP was evident. A strong effect could lead to rupture of some of the CAP thrombosed aneurysmal models. Besides, stenosis or occlusion of the parent arteries could be induced in some cases after embolization with CAP. For the above shortcomings and limitations, it should be improved carefully before it is applied in clinic.

[Experiences with the endovascular embolization therapy of aneurysms of the splanchnic arteries--a report on 13 cases]. / Erfahrungen mit der endovaskulären Embolisationstherapie von Aneurysmata der Splanchnikusarterien--Bericht über 13 Fälle.

PURPOSE: The authors report on their experience in endovascular embolization therapy in 13 cases with splanchnic artery aneurysms or pseudoaneurysms. PATIENTS AND METHODS: Three patients suffered from true aneurysms, ten patients presented pseudoaneurysms of different origin. Eight patients were transferred to our department for life-threatening intestinal bleeding. Five patients showed transpapillary bleeding, four of whom presented with haemobilia and one patient had intermittent bleeding into the pancreatic duct due to a true aneurysm of the splenic artery. Embolization was performed using a coaxial microcatheter coil delivery system. In 4 patients the aneurysm-bearing vessel was temporarily blocked during the intervention. RESULTS: In 11 patients definite occlusion of the aneurysm was obtained without surgical intervention. In one patient, suffering from a splenic aneurysm, we observed a partial inadvertent embolisation of the spleen which did not require further treatment. In one case, rupture of an hepatic aneurysm during embolization occurred. One patient with pseudoaneurysm due to displacement of a port catheter showed severe rebleeding one day after embolisation. CONCLUSION: Transcatheter embolization is an effective method for treatment of aneurysms of the splanchnic arteries. To avoid life-threatening bleeding due to rupture of the aneurysm, the feeding vessel should be temporarily blocked during embolization therapy.