Balloon-Assisted Portal Vein Embolization Using n-Butyl-2-Cyanoacrylate-Lipiodol-Iopamidol Mixture in Swine: A Comparison of 2 Formulations.

PURPOSE: To compare 2 ratios of n-butyl-2-cyanoacrylate (nBCA)-ethiodized oil (Lipiodol)-iopamidol (NLI) in balloon-assisted portal vein embolization (PVE) in swine. MATERIALS AND METHODS: In an in vitro study, NLI prepared at a ratio of 2:3:1 (NLI231) or 1:4:1 (NLI141) was injected into 2.5- or 10-mL syringes filled with swine blood, and the viscosity of NLI was measured to determine an appropriate balloon occlusion time. Two portal vein branches in 8 female swine (n = 16 vein branches) were embolized with NLI231 (n = 8) or NLI141 (n = 8) under balloon occlusion. Portal venography was performed before, immediately after, and 3 days after PVE to evaluate the migration of NLI and the recanalization of embolized portal vein branches. Then, the livers were removed for histopathologic evaluation. RESULTS: The times to peak viscosity of NLI231 in the 2.5- and 10-mL syringes were 55.8 seconds (SD ± 7.0) and 85.2 seconds (SD ± 6.3), and those to peak viscosity of NLI141 were 129.2 seconds (SD ± 11.8) and 254.0 seconds (SD ± 21.8), respectively. No migration of NLI231 was observed in all 8 procedures immediately or 3 days after PVE. Migration of NLI141 was observed in 6 of 8 procedures within 3 days after PVE. The migration frequency of the embolic material was lower in the NI231 group than in the NLI141 group (0/8 vs 6/8; P = .051). Histologically, NLI231 occupied the portal veins without any thrombi, whereas NLI141 was accompanied by thrombi in the portal veins. CONCLUSIONS: NLI231 may be more suitable than NLI141 for balloon-assisted PVE in swine.

Usefulness of ethiodized oil and gelatin sponge particles for delaying the washout of indocyanine green from the liver in swine.

PURPOSE: To assess the effect of ethiodized oil (EO) and gelatin sponge particles (GS) on delaying the washout of indocyanine green (ICG) from the liver in swine. METHODS: Fifteen swine were divided into 3 groups: injection of a mixture of ICG and water-soluble contrast medium (CM) followed by embolization with GS (group A), injection of a mixture of ICG and EO (group B) and injection of a mixture of ICG and EO followed by embolization with GS (group C). The liver surface was observed using an infrared camera system during and at 1, 2, 3, and 6 h after the procedure to measure ICG contrast. Livers were removed at 6 h for histopathological examination. RESULTS: The contrast ratio between injected and non-injected regions at 6 h was 1.45 ± 0.44 in group A, 1.89 ± 0.37 in group B, and 3.62 ± 0.76 in group C. The contrast ratio in group C was significantly greater than that in groups A and B (P = 0.032 and 0.033, respectively). CONCLUSIONS: EO and GS delayed the washout of ICG from the liver in swine and may extend intraoperative navigation in clinical use. Indocyanine green (ICG) mixed with ethiodized oil (EO) was injected into the left hepatic artery in swine, and the artery was embolized with gelatin sponge particles (GS). We confirmed that ICG remained in the liver parenchyma up to 6 h after the procedure. EO and GS delayed the washout of ICG from the liver 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.

Prophylactic Intraoperative Embolization of Abdominal Aortic Aneurysm Sacs Using N-Butyl Cyanoacrylate/Lipiodol/Ethanol Mixture with Proximal Neck Aortic Balloon Occlusion during Endovascular Abdominal Aortic Repair.

PURPOSE: To determine the feasibility of prophylactic intraoperative abdominal aortic aneurysm (AAA) sac embolization using a mixture of N-butyl cyanoacrylate/Lipiodol/ethanol (NLE) with proximal neck aortic balloon occlusion during endovascular aneurysm repair (EVAR) to prevent the occurrence of endoleak and aneurysm sac expansion. MATERIALS AND METHODS: Prophylactic intraoperative AAA sac embolization was performed in 24 patients with an infrarenal neck angulation > 60° (n = 16) or AAA sac diameter > 60 mm (n = 17). AAA sac pressure was continuously measured with a 3-F catheter inserted into the AAA sac. The systolic sac pressure index (SPI) was calculated as the ratio of systolic AAA sac pressure to the simultaneously measured systolic aortic pressure, and was measured with and without proximal neck aortic balloon occlusion. The aneurysm sac was embolized with NLE during proximal neck aortic balloon occlusion immediately after EVAR. Endoleak and AAA sac diameter were evaluated by enhanced computed tomography and subtraction magnetic resonance imaging at 6 months and yearly after EVAR. RESULTS: Mean SPIs after EVAR with and without proximal neck aortic balloon occlusion were 0.36 and 0.57, respectively. There were no adverse events related to intraoperative sac embolization. Follow-up imaging (mean, 12.1 mo) revealed three minor endoleaks (12.5%) and no aneurysm sac expansion. CONCLUSIONS: Prophylactic intraoperative sac embolization with NLE during proximal neck aortic balloon occlusion was safe and feasible and may reduce endoleaks and prevent sac expansion after EVAR in patients with unfavorable anatomic factors.

Clinical evaluation of transcatheter arterial chemoembolization with 2-day-soluble gelatin sponge particles for hepatocellular carcinoma-comparison with insoluble gelatin sponge particles.

PURPOSE: To compare therapeutic effect, adverse events, and embolized hepatic artery impairment in transcatheter arterial chemoembolization between Lipiodol plus insoluble gelatin sponge particles (Gelpart) and Lipiodol plus 2-day-soluble gelatin sponge particles (2DS-GSPs). MATERIALS AND METHODS: In a single-center, prospective, randomized controlled trial, patients with hepatocellular carcinoma were assigned to the 2DS-GSP group or the Gelpart group. Radiographic response at 3 months per modified Response Evaluation Criteria In Solid Tumors was evaluated as the primary endpoint; secondary endpoints were safety (per Common Terminology Criteria for Adverse Events, version 4.0) within 3 months and hepatic branch artery impairment at the time of repeat chemoembolization (grade 0, no damage; grade I, mild vessel wall irregularity; grade II, overt stenosis; grade III, occlusion of more peripheral branch artery than subsegmental artery; grade IV, occlusion of subsegmental artery). Grade II, III, or IV indicated significant hepatic artery impairment. RESULTS: Thirty-seven patients with 143 nodules were randomized to the 2DS-GSP group and 36 patients with 137 nodules were randomized to the Gelpart group. No significant differences in patient background existed between groups. Target lesion response and overall tumor response in the 2DS-GSP and Gelpart groups were 77.7% versus 76.9% and 78.3% versus 77.8%, respectively, with no significant differences. No significant difference in adverse events existed between groups. Hepatic artery impairment was observed in 5% of patients in the 2DS-GSP group (n = 32) and in 16% in the Gelpart group (n = 33; P< .001). CONCLUSIONS: Transcatheter arterial chemoembolization with 2DS-GSPs resulted in the same therapeutic and adverse effects as chemoembolization with Gelpart while causing significantly less hepatic artery impairment.