Retrograde embolization of internal iliac artery aneurysms that enlarged after proximal ligation: A report of 5 patients.

The transarterial approach is generally feasible for endovascular treatment of internal iliac artery aneurysms (IIAAs). However, this approach becomes difficult in patients who have undergone exclusion surgery (proximal ligation). We report our experience of performing transcatheter arterial embolization (TAE) using a retrograde approach from the deep femoral artery (DFA) for IIAAs that had enlarged after exclusion surgery. This case series includes 5 male patients (mean age, 57 years; range, 66-81 years) who underwent TAE of IIAAs between March 2015 and March 2024. The procedures were performed at a mean of 47 months (range, 33-108 months) after aortoiliac repair. Preoperative contrast-enhanced computed tomography (CT) or CT during aortography was performed before TAE in all cases to evaluate the development of collateral pathways. TAE was performed via the DFA using a retrograde approach with coils and cyanoacrylate glue in all cases. The procedure was technically successful in all 5 patients (100%). Intra-aneurysmal packing and embolization of the branched vessel was performed in all cases. The follow-up ranged from 6 to 66 months. All patients developed gluteal claudication but no major complications occurred during the follow-up period. No cases of aneurysm dilatation have been recorded to date. In conclusion, retrograde TAE of excluded IIAAs was a feasible and effective treatment in these 5 patients, after evaluating the development of collateral pathways on pretreatment contrast-enhanced CT.

An anomalous left adrenal vein draining into both the left renal vein and inferior vena cava: A case report.

A male patient in his forties was diagnosed with primary aldosteronism following blood tests. The patient requested surgical treatment and was transferred to our department for adrenal vein sampling. Preoperative contrast-enhanced computed tomography (CT) revealed that the left adrenal vein (LAV) did not form a common trunk with the left inferior phrenic vein, and instead drained into both the left renal vein (LRV) and inferior vena cava (IVC) after the bifurcation. Angiography from the LAV showed a branch draining into the IVC. Left-sided sampling was performed. Aldosterone levels were elevated at all 3 sites. Because the sampling results were bilaterally positive, the patient was contraindicated for surgery. There are no reports of an anomalous LAV draining into both the LRV and IVC, making this case extremely unique. Regarding the LAV sampling site, it has been reported that aldosterone levels are higher in the common trunk than in the LAV. Therefore, we increased the number of blood sampling sites. In adrenal vein sampling, we often focus on the anatomy of the right adrenal vein because of difficulties in accessing to it. However, anomalies of the LAV may also occur. Therefore, it is important to determine the anatomy of both adrenal veins using preoperative contrast-enhanced CT to plan an appropriate sampling strategy.

Vascular type Ehlers-Danlos syndrome with intra-abdominal hemorrhage due to ruptured hepatic aneurysm: A case report.

Background: Vascular Ehlers-Danlos syndrome has a high mortality rate due to hemorrhagic complications. Case Presentation: We report a case of vascular-type Ehlers-Danlos syndrome diagnosed due to rupture of multiple celiac aneurysms. The patient was a 25-year-old Japanese man with a history of a sigmoid perforation. He was admitted to a nearby hospital because of abdominal pain. On day 9 of hospitalization, the patient experienced shock. Enhanced abdominal computed tomography revealed a hepatic aneurysm and intra-abdominal bleeding, and the patient was transferred to our hospital. Emergency abdominal angiography revealed multiple aneurysms in the celiac, common, and right hepatic arteries. The right hepatic artery was considered responsible and was embolized. The patient had characteristic physical findings of the syndrome, aiding in confirming the genetic analysis of COL3A1 gene abnormality. Conclusion: Juvenile-onset colonic perforation and rupture of the celiac arteries are key findings in the suspicion of vascular-type Ehlers-Danlos syndrome.

Successful retrieval of a foreign body in an infant's right pulmonary artery using the new boomerang loop-snare technique: A case report.

We report successful percutaneous retrieval of a foreign body located in an infant's right pulmonary artery using the new boomerang loop-snare technique. The case was an 18-month-old girl. A central venous catheter for chemotherapy was inserted from the right subclavian vein during treatment for myelodysplastic syndrome at another hospital. A postprocedural chest X-ray showed a foreign body in her right lung, and contrast-enhanced computed tomography confirmed the linear foreign body was located in the right pulmonary artery. The patient was transferred to our hospital to retrieve the foreign body. Under cooperation with pediatric cardiologists, a 6 Fr sheath was inserted via the right femoral vein, and a guiding catheter was advanced into the right pulmonary artery. Owing to the risk of vascular injury when using endoscopic forceps, we decided to use the loop-snare technique. We successfully crossed over the foreign body using a steerable microcatheter and a long microguidewire. The microguidewire was reinserted into the guiding catheter, and a loop was created by grasping the end of the wire using a microsnare catheter, which was inserted coaxially within the guiding catheter. By pulling the microsnare catheter, we were able to pull the foreign body into the guiding catheter and successfully retrieved it. There were no complications, such as pulmonary artery injuries or thrombi. The recovered foreign body was a piece of a guidewire. The boomerang loop-snare technique using a small-diameter system is useful for the retrieval of a foreign body in infants.

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.

Double Negativity of MRI-Detected and Pathologically-Diagnosed Extramural Venous Invasion is a Favorable Prognostic Factor for Rectal Cancer.

BACKGROUND: Extramural venous invasion (EMVI) is a prognostic factor in rectal cancer. There are two types: EMVI detected by magnetic resonance imaging (MRI) (mr-EMVI) and EMVI detected by pathology (p-EMVI). They have been separately evaluated, but they have not yet been concurrently evaluated. We therefore evaluate both mr-EMVI and p-EMVI in rectal cancer at the same time and clarify their association with prognosis. PATIENTS AND METHODS: Included were the 186 consecutive patients who underwent complete radical resection of tumors ≤ stage III at Wakayama Medical University Hospital, Japan, between 2010 and 2018. All underwent preoperative MRI examination, and were reassessed for EMVI by a radiologist. Surgically resected specimens were then reassessed for EMVI by a pathologist. We assessed the correlation between positivity of mr-EMVI and p-EMVI and prognosis, and the clinicopathological background behind them. RESULTS: Patients with double negativity for mr-EMVI and p-EMVI had better prognosis than patients with mr-EMVI or p-EMVI positivity (p < 0.0001). Positivity for mr-EMVI or p-EMVI was a poor independent prognostic factor in multivariate analysis. CONCLUSIONS: Combined analysis of mr-EMVI and p-EMVI may enable prediction of postoperative prognosis of rectal cancer. Patients with double negativity of mr-EMVI and p-EMVI had better prognosis than patients with some form of positivity. Stated differently, patients with positivity of mr-EMVI, p-EMVI, or both had a poorer prognosis than those with double negativity. Postoperative adjuvant chemotherapy may improve poor prognosis. Combined evaluation of mr-EMVI and p-EMVI may be used to predict clinical outcomes and may be an effective prognostic predictor of rectal cancer.

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.

Duodenal bleeding outside covered stents identified by selective computed tomography during arteriography that was successfully treated by embolization: A case report.

The patient was a man in his 60s who previously underwent placement of covered stents in the duodenum for a duodenal stricture caused by pancreatic cancer invasion. He experienced multiple episodes of hematemesis and hematochezia during hospitalization. Emergency upper and lower gastrointestinal endoscopies were performed but were unable to reveal the bleeding source. Based on these findings, we suspected small intestinal bleeding and emergency angiography was performed for the purpose of hemostasis. Computed tomography during arteriography was performed from the superior mesenteric artery and revealed extravasation outside the covered stents in the descending portion of the duodenum. Angiography of the inferior pancreaticoduodenal artery revealed extravasation in the descending portion of the duodenum, and the inferior pancreaticoduodenal artery was embolized with n-butyl cyanoacrylate. There were no postoperative symptoms indicative of intestinal ischemia or pancreatitis, and there was no rebleeding after embolization. In patients with bleeding outside the duodenal-covered stents, it can be difficult to identify the bleeding source by upper gastrointestinal endoscopy. In this case, selective computed tomography during arteriography and angiography revealed bleeding outside the duodenal-covered stents that was successfully treated by arterial embolization with n-butyl cyanoacrylate.

Radiological Shape of the Tumor Predicts Progression and Survival in Resected Extrahepatic Cholangiocarcinoma.

BACKGROUND: The histological features and radiological shape of extrahepatic cholangiocarcinoma (eCCA) have not been widely studied in relation to prognosis. Multi-detector computed tomography (MDCT) is thought to be useful in diagnosis of progress and tumor distribution; it can also show morphological differences (round, triangular, and square forms) at the tumoral obstruction sites. Histological types of eCCA may be revealed, with potential association with tumor growth and survival. METHODS: We examined the distribution of tumor radiological shape subtypes on MDCT. The surgical outcomes of consecutive patients with eCCA who underwent macroscopic curative resection were reviewed. RESULTS: CT subtypes in 109 patients were 62 triangular, 35 square, and 12 round. There were clear prognostic differences in long-term survival rates (P < 0.001); 5-year survival rates were 100% in round, 64% in triangular, and 19% in square types. There was no recurrence in any cases of round-type tumor at the site of obstruction. Depth of tumor invasion and rates of nodal involvement were significantly higher in triangular and square-type tumors than in round-type tumors. In papillary adenocarcinoma, radiological obstructions were round type in seven patients (78%) and triangular type in two patients (22%). In tubular adenocarcinoma, all round-type tumors were well differentiated, the ratio of square-type tumors increasing as the degree of differentiation decreased from "well" to "moderate," and "poor" respectively (23%, 39%, 57%; P = 0.033). CONCLUSIONS: Tumor radiological shape predicts tumor progression, histological type, and survival in eCCA. This information may be helpful in preoperative radiological staging on MDCT.

Permissive untreated pseudoaneurysm concept in damage control interventional radiology for traumatic pancreaticoduodenal artery injury.

Background: Angioembolization for traumatic pancreaticoduodenal artery injury with unstable circulation, which characteristically requires a prolonged procedure time, does not yet have a standardized strategy for damage control interventional radiology. Case Presentation: We encountered two cases of rare traumatic pancreaticoduodenal artery injury wherein the patients were saved by a multidisciplinary team with a shared goal of clinical success, rather than the procedural success of angioembolization. Both patients treated with angioembolization had residual pseudoaneurysm or faint extravasation in the pancreaticoduodenal artery arcade. We prioritized critical care with preemptive plasma transfusion and aggressive blood pressure control, and planned repeat angiography. The patients showed no clinical signs of rebleeding or pseudoaneurysm based on computed tomography during follow-up. Conclusion: Our findings suggest that the permissive untreated pseudoaneurysm concept can be useful in developing damage control interventional radiology strategies for trauma cases with challenging time limitations, such as traumatic pancreaticoduodenal artery injury with circulatory collapse.

Percutaneous transsplenic venous embolization of elevated jejunal varices after pancreaticoduodenectomy: A case report.

Recent advances in chemotherapy and radiotherapy have led to an increase in the number of long-term survivors of pancreatic cancer. However, this has also increased the number of patients suffering from ectopic varices and bleeding owing to left-sided portal hypertension and thrombocytopenia caused by splenomegaly after pancreaticoduodenectomy combined with resection of the splenic vein. A 65-year-old woman with varices of the elevated jejunum due to left sided portal hypertension after pancreaticoduodenectomy had repeated melena, which started about 1 year before admission. We describe the first reported case of percutaneous transsplenic venous embolization using metallic coils, which successfully achieved hemostasis of refractory bleeding from the elevated jejunal varices after pancreaticoduodenectomy.

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.

Outcomes of embolization procedures for type II endoleaks following endovascular abdominal aortic repair.

OBJECTIVE: The objective of this study was to investigate the mid-term outcomes of embolization procedures for type II endoleak after endovascular abdominal aortic repair, and clarify the risk factors for aneurysm enlargement after embolization procedures. METHODS: This was a retrospective multicenter registry study enrolling patients who underwent embolization procedures for type II endoleaks after EVAR from January 2012 to December 2018 at 19 Japanese centers. The primary end point was the rate of freedom from aneurysm enlargement, more than 5 mm in the aortic maximum diameter, after an embolization procedure. Demographic, procedural, follow-up, and laboratory data were collected. Continuous variables were summarized descriptively, and Kaplan-Meier analyses and a Cox regression model were used for statistical analyses. RESULTS: A total of 315 patients (248 men and 67 women) were enrolled. The average duration from the initial embolization procedure to the last follow-up was 31.6 ± 24.6 months. The rates of freedom from aneurysm enlargement at 3 and 5 years were 55.4 ± 3.8% and 37.0 ± 5.2%, respectively. A multivariate analysis revealed that a larger aortic diameter at the initial embolization procedure and the presence of a Moyamoya endoleak, defined as heterogeneous contrast opacity with an indistinct faint border, were associated with aneurysm enlargement after embolization management. CONCLUSIONS: The embolization procedures were generally ineffective in preventing further expansion of abdominal aortic aneurysms in patients with type II endoleaks after EVAR, especially in patients with a large abdominal aortic aneurysm and/or a presence of a Moyamoya endoleak.

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.