Impact of sarcopenia on recurrent biliary obstruction after EUS-guided biliary drainage in patients with malignant biliary obstruction.

BACKGROUND AND AIMS: Sarcopenia is an important prognostic factor for cancer patients. The aim of this study was to assess the ability of sarcopenia to predict recurrent biliary obstruction (RBO) in patients with unresectable cancer after EUS-guided biliary drainage (EUS-BD). METHODS: The study enrolled 113 patients who underwent EUS-BD using the self-expandable metal stent (SEMS) for unresectable malignant biliary obstruction (MBO) between April 2016 and December 2021 at Wakayama Medical University Hospital. The skeletal muscle index at the third lumbar spine level (L3) was calculated from computed tomography images. We analyzed the cumulative incidence of RBO at 180 days after stent insertion. Univariate and multivariate analyses were performed to identify variables significantly associated with RBO. RESULTS: Seventy-six patients were assigned to the sarcopenia group, and 37 were assigned to the non-sarcopenia group. The 180-day cumulative incidence of RBO was 11% in the non-sarcopenia group and 29% in the sarcopenia group (p = 0.034). The time to RBO was significantly shorter for the sarcopenia group (p = 0.028; Gray's test). Multivariate analyses identified sarcopenia as an independent prognostic factor for RBO (present vs absent; HR 4.61; 95% CI 1.76-12.10, p = 0.001). The rates of biliary sludge/food impaction were significantly higher in the sarcopenia group for the causes of RBO (p = 0.048). There were no significant differences between the sarcopenia and the non-sarcopenia groups with respect to related EUS-BD adverse events. CONCLUSION: Sarcopenia is an independent indicator of RBO in patients with MBO who receive EUS-BD with SEMS.

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.

Comparison of Renal Damage Following Renal Artery Embolization with Three Different Embolic Mixtures in Swine.

Purpose: Renal artery embolization is a minimally invasive and effective procedure for renal ablation, a complete necrosis of the renal parenchyma. This study aims to compare the extent of renal damage in swine following renal artery embolization with ethanol and N-butyl-2-cyanoacrylate, commonly used as embolic materials in renal ablation. Material and Methods: Three different embolic mixtures were prepared for renal artery embolization in swine: 33% ethanol-Lipiodol mixture (ethanol:Lipiodol = 1:2; Group A), 67% ethanol-Lipiodol mixture (ethanol:Lipiodol = 2:1; Group B), and 10% N-butyl-2-cyanoacrylate-Lipiodol mixture (N-butyl-2-cyanoacrylate:Lipiodol = 1:9; Group C). Three swine were assigned to each group and underwent embolization of the unilateral renal artery. Renal arteriography was performed before, immediately after, and two days after renal artery embolization. After two days, the kidneys were removed to determine the macroscopic necrosis rate and for histologic examination. Dark tissue regions were considered necrotic. Results: The macroscopic necrosis rate of the kidneys was 50.3%±7.4%, 100%±0%, and 100%±0% in Groups A, B, and C, respectively. The necrosis rates were higher in Groups B and C than in Group A. Histologically, the renal tubules were damaged in the necrotic areas. In addition, the glomeruli were damaged in Groups A and B but were preserved in Group C. Conclusions: Sixty-seven percent ethanol-Lipiodol mixture and 10% N-butyl-2-cyanoacrylate-Lipiodol mixture are effective embolic materials in renal artery embolization for renal ablation in swine. Also, ethanol caused partial glomerular necrosis, whereas N-butyl-2-cyanoacrylate preserved the glomeruli. Therefore, ethanol should be used for renal ablation.

Feasibility of the Glue-in-Plug Technique Using a Novel Liquid Embolic Material in a Swine Model.

PURPOSE: To evaluate the feasibility of the glue-in-plug (GIP) technique using n-butyl-2-cyanoacrylate‒Lipiodol (NL)-iopamidol (NLI) for short-segment embolization in swine. MATERIALS AND METHODS: The renal arteries, left external iliac artery, subclavian arteries, and common carotid arteries were each embolized in 4 swine using the GIP technique under general anesthesia. First, a type I Amplatzer vascular plug (AVP) (1-2 times the target vessel diameter) was deployed in the target artery. Next, the AVP was filled with NL mixture prepared at a ratio of 1:2 (NL12) (n = 11) or with NLI mixture prepared at a ratio of 2:3:1 (NLI231) (n = 11). Angiography was performed before, immediately after, and 1 hour after embolization to assess embolization and migration of the embolic materials. The embolized arteries were also evaluated histopathologically. RESULTS: The migration distance of the embolic material beyond the plug tip was significantly shorter in the NLI231 group than in the NL12 group immediately after embolization (6.5 mm ± 4.5 vs 1.0 mm ± 1.8, P = .0024) and 1 hour after embolization (8.4 mm ± 5.6 vs 1.0 mm ± 1.8, P = .0013). Angiography revealed no sign of recanalization of the target vessels in any artery in either group. Mild inflammatory cell infiltration was observed around the arterial wall at the embolization site in all arteries in both groups. CONCLUSIONS: The GIP technique using NLI231 may be a feasible procedure for short-segment embolization based on these short-term results.

Comparison of Soluble Gelatin Sponge Particles and Tris-acryl Gelatin Microspheres for Bariatric Arterial Embolization in Swine.

The purpose of this study was to compare complications and the number of ghrelin-expressing cells (GECs) after bariatric arterial embolization (BAE) using soluble gelatin sponge particles (SGSs) or tris-acryl gelatin microspheres (MSs) in swine. Twelve swine underwent embolization of gastric fundal arteries with SGSs (n = 4) or MSs (n = 4) or underwent saline infusion (n = 4, control group). One week later, the number of gastric ulcers and the percentage of GECs were compared among the 3 groups. There were no ulcers in the SGS and control groups. Two swine in the MS group had 4 large ulcers (12-50 mm in size). The mean percentages of GECs were significantly lower in the SGS (2.7% ± 0.9%) and MS (2.5% ± 1.0%) groups compared with the control group (3.7% ± 1.3%; P = .038 and P = .016, respectively). SGSs may be safer than MSs for BAE while inducing a similar reduction of GECs 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.

Transcatheter arterial embolization of abnormal neovessels in a swine model of knee arthritis.

BACKGROUND: In recent years, transcatheter arterial embolization (TAE) using imipenem/cilastatin (IPM/CS) has attracted attention as a treatment for relieving osteoarthritis (OA) pain. However, IPM/CS is not approved by Japanese medical insurance for use as an embolic material. Therefore, it is necessary to develop new embolic materials for TAE to relieve OA pain. The purpose of this study was to develop a swine model of knee arthritis and embolize abnormal neovessels (ANs) using two different embolic materials. We compared the embolic effects and tissue damage in knees. METHODS: Knee arthritis was induced by intra-articular injection of papain into 12 knees in six female swine. The swine were divided into two groups of three swine each (six knees per group) for embolization of ANs in the knees with either IPM/CS or soluble gelatin sponge particles (SGSs). Three days after embolization, we compared the embolic effects using angiography and the tissue damage histopathologically. RESULTS: ANs were observed in all 12 knees at 42 days after papain injection. The ANs disappeared and the patent arteries were recanalized 3 days after TAE in all 12 knees. Histopathological evaluation revealed synovitis changes, such as synovial thickening and inflammatory cell infiltration, in all 12 knees. There was no evidence of skin or muscle necrosis in either group. The appearance of ANs, recanalization of the parent arteries, and histopathological outcomes were not significantly different between the two groups. CONCLUSION: SGSs were as safe as IPM/CS for TAE of ANs in this swine model of knee arthritis.

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.

Impact of sarcopenia on prediction of progression-free survival and overall survival of patients with pancreatic ductal adenocarcinoma receiving first-line gemcitabine and nab-paclitaxel chemotherapy.

BACKGROUND AND AIMS: Sarcopenia is an important prognostic factor for cancer patients. Here, we assessed the effects of sarcopenia on progression-free survival (PFS) and overall survival (OS) of patients with pancreatic ductal adenocarcinoma (PDAC) who underwent treatment with first-line gemcitabine and nab-paclitaxel (GEM and nab-PTX). METHODS: The study enrolled patients with unresectable PDAC who underwent chemotherapy between April 2016 and May 2020. The skeletal muscle index (SMI) at the third lumbar spine level (L3) was calculated from computed tomography (CT) images. Propensity score analysis was used to compare PFS and OS in the sarcopenia and non-sarcopenia groups. Univariate and multivariate analyses were performed to determine variables significantly associated with prognosis. RESULTS: Of the 176 patients who received first-line GEM and nab-PTX, 84 were selected and divided into two groups of 42 (the sarcopenia and the non-sarcopenia groups) by propensity score matching. The median PFS of the sarcopenia and the non-sarcopenia groups was 5.0 and 8.0 months, respectively (p = 0.004). The median OS was 10.3 and 18.1 months, respectively (p = 0.001). Multivariate analyses revealed that sarcopenia was an independent prognostic factor for PFS and OS (p = 0.004, p = 0.001, respectively). The rates of major grade 3 or 4 AEs were significantly higher in the sarcopenia group (p = 0.008). CONCLUSIONS: Sarcopenia is an independent indicator of a poor prognosis in patients with PDAC treated with first-line GEM and nab-PTX.

Value of contrast-enhanced harmonic endoscopic ultrasound for diagnosing hepatic metastases of pancreatic cancer: A prospective study.

BACKGROUND AND AIMS: This study aimed to compare contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) with fundamental B-mode endoscopic ultrasonography (EUS) and contrast-enhanced computed tomography (CE-CT) for the diagnosis of left hepatic lobe metastases of pancreatic adenocarcinoma. METHODS: In this single-center prospective study, CE-CT, EUS, and CH-EUS were performed to detect left hepatic lobe metastases in patients with pancreatic adenocarcinoma, and the detection rates were compared between EUS plus CH-EUS and the other two modalities. Subgroup comparisons of between-modality detection rate were performed in patients with only metastases of <10 mm. The number of pancreatic adenocarcinoma patients whose clinical stage and treatment strategy were changed because of EUS plus CH-EUS findings was also assessed. RESULTS: Thirty-one patients were diagnosed with left hepatic lobe metastases. For overall detection of left hepatic lobe metastases, EUS plus CH-EUS had significantly higher accuracy (94.3%) than CE-CT (86.7%) and EUS alone (87.6%) (P = 0.021 and P = 0.020, respectively). For detection of left hepatic lobe metastases < 10 mm, EUS plus CH-EUS (93.3%) was significantly superior to CE-CT (84.4%) and EUS alone (85.6%) (P = 0.021 and P = 0.020, respectively). In five of the 11 patients in whom only CH-EUS allowed detection of hepatic metastases, the stage and/or treatment strategy of the pancreatic adenocarcinoma was changed after CH-EUS. CONCLUSION: This study demonstrated that EUS plus CH-EUS has advantages over CE-CT and EUS alone with regard to the accuracy of detecting left hepatic lobe metastases, particularly small hepatic metastases and accurate staging.

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.

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.

Abrupt spin transition with thermal hysteresis of iron(III) complex [Fe(III)(Him)2(hapen)]AsF6 (Him = imidazole, H2hapen = N,N'-bis(2-hydroxyacetophenylidene)ethylenediamine).

The solvent-free spin crossover iron(III) complex [Fe(III)(Him)2(hapen)]AsF6 (Him = imidazole, H2hapen = N,N'-bis(2-hydroxyacetophenylidene)ethylenediamine), exhibiting thermal hysteresis, was synthesized and characterized. The Fe(III) ion has an octahedral coordination geometry, with N2O2 donor atoms of the planar tetradentate ligand (hapen) and two nitrogen atoms of two imidazoles at the axial positions. One of two imidazoles is hydrogen-bonded to the phenoxo oxygen atom of hapen of the adjacent unit to give a hydrogen-bonded one-dimensional chain, while the other imidazole group is free from hydrogen bonding. The temperature dependencies of the magnetic susceptibilities and Mössbauer spectra revealed an abrupt spin transition between the high-spin (S = 5/2) and low-spin (S = 1/2) states, with thermal hysteresis.