Successful coil embolization of post-hepatectomy arterioportal fistula that reduced ascites and improved liver function.

A 71-year-old man had previously undergone S7 + S8 dorsal segmentectomy and S5 partial hepatectomy for hepatocellular carcinomas. Six months later, he experienced abdominal distention. Abdominal computed tomography (CT) showed massive ascites and a significant hepatic arterioportal shunt. The ascites was thought to be caused by portal hypertension due to a high-flow hepatic arterioportal fistula (HAPF). The fistula, located between the right hepatic artery A7 and the right portal vein, was embolized with microcoils under flow control using a balloon catheter. After embolization, the shunt blood flow disappeared and the hepatopetal venous flow was restored. His body weight and abdominal circumference decreased immediately, and his liver function on blood tests improved after the procedure. CT performed 11 days after embolization showed decreased ascites. A HAPF after hepatectomy is extremely rare. Balloon-assisted embolization using microcoils is a useful endovascular procedure for treating a high-flow HAPF.

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.

Successful coil embolization of a ruptured aneurysm of the arc of Riolan artery.

The arc of Riolan (AOR) is an anastomosis between the middle and left colic arteries. Aneurysms of the AOR are very rare visceral artery aneurysms. A 44-year-old man presented with abdominal pain and loss of consciousness. Computed tomography and angiography showed hemorrhagic ascites around the liver and spleen. An irregularly dilated artery was visible within a hematoma in the upper left region of the abdomen, consistent with a ruptured pseudoaneurysm of the AOR. Transcatheter arterial embolization was performed with microcoils. The patient's abdominal pain disappeared after embolization, and no symptoms of intestinal ischemia were observed. To our knowledge, this is the first case of an AOR aneurysm with AOR dilation due to dissection of the celiac artery that was successfully treated by coil embolization.

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.

Comparison of Uterine Necrosis After Uterine Artery Embolization with Soluble Gelatin Sponge Particles or Tris-acryl Gelatin Microspheres in Swine.

PURPOSE: To compare the recanalization of the uterine arteries and uterine necrosis after uterine artery embolization (UAE) using either soluble gelatin sponge particles (SGS), which dissolve in saline, or tris-acryl gelatin microspheres (MS), which are permanent embolic materials, in swine. METHODS: Fourteen uteri in seven swine were divided into two groups for embolization with either 500-1000 µm SGS (SGS group) or 500-700 µm MS (MS group) (seven uteri per group). The uterine arteries were embolized using SGS or MS, and angiography was performed to evaluate recanalization of the uterine arteries immediately, 1, 2, 3, 4, 5, and 6 h, and 3 days after embolization. On day 3, the uteri were removed to determine the macroscopic necrosis rate and for histopathologic examination. RESULTS: In the SGS group, four uterine arteries were completely recanalized, two were partially recanalized, and one was still occluded 5 h after embolization. In contrast, all seven uterine arteries in the MS group were still occluded 6 h after embolization. The complete recanalization rate at 3 days was significantly greater in the SGS group than in the MS group (100.0% vs. 14.3%, respectively; P = .0047). The mean uterine necrosis rate was not significantly different between the SGS and MS groups (15.0 ± 15.7% vs. 26.8 ± 13.3%, respectively; P = .096). The mean smallest arterial diameter containing embolic materials was 48.2 ± 22.0 µm (range 21-109 µm) for SGS and 446.7 ± 107.0 µm (range 352-742 µm) for MS (P < .0001). CONCLUSION: The uterine arteries recanalized earlier in the SGS group than in the MS group and the uterine necrosis rates were similar in both groups. SGS have the potential for a more distal penetration in comparison with MS.

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.

Hepatic Arterial Embolization with an Indocyanine Green-LipiodolⓇ Mixture before Laparoscopic Anatomical Liver Resection.

Here, we report a case of hepatocellular carcinoma detected on computed tomography and treated with laparoscopic anatomical liver resection in a 69-year-old woman who was being followed-up for hepatitis C. Intraoperative liver segmentation is necessary to accomplish laparoscopic anatomical liver resection. Therefore, the day before surgery, hepatic artery embolization was performed with an indocyanine green-LipiodolⓇ mixture and GelpartⓇ containing indocyanine green to mark the region for hepatectomy. The next day, surgeons visually confirmed the resection segments on indocyanine green fluorescence imaging and performed laparoscopic anatomical liver resection. No major complications resulted from this method. In conclusion, hepatic artery embolization with an indocyanine green-LipiodolⓇ mixture is effective and safe for liver segment identification during laparoscopic anatomical liver resection.