In Vivo Sonoporation Effect Under the Presence of a Large Amount of Micro-Nano Bubbles in Swine Liver.

OBJECTIVES: Sonoporation as a method of intracellular drug and gene delivery has not yet progressed to being used in vivo. The aim of this study was to prove the feasibility of sonoporation at a level practical for use in vivo by using a large amount of carbon dioxide micro-nano bubbles. METHODS: The carbon dioxide micro-nano bubbles and 100 mg of cisplatin were intra-arterially injected to the swine livers, and ultrasound irradiation was performed from the surface of the liver under laparotomy during the intra-arterial injection. After the intra-arterial injection, ultrasound-irradiated and nonirradiated liver tissues were immediately excised. Tissue platinum concentration was measured using inductively coupled plasma mass spectrometry. Liver tissue platinum concentrations were compared between the irradiated tissue and nonirradiated tissue using the Wilcoxon signed rank test. RESULTS: The mean (SD) liver tissue platinum concentration was 6.260*103 (2.070) ng/g in the irradiated liver tissue and 3.280*103 (0.430) ng/g in the nonirradiated liver tissue, showing significantly higher concentrations in the irradiated tissue (P = 0.004). CONCLUSIONS: In conclusion, increasing the tissue concentration of administered cisplatin in the livers of living swine through the effect of sonoporation was possible in the presence of a large amount of micro-nano bubbles.

Venous Rupture Following Transcatheter Arterial Embolization for Inferior Mesenteric Type II Arteriovenous Malformation.

We treated a 64-year-old man who had an inferior mesenteric arteriovenous malformation with multiple shunts. As multiple varicosities in the draining vein became enlarged, two dilated shunts on the superior rectal and sigmoid colon arteries were coil embolized. Two days after embolization, a varicosity near the shunt (65 mm diameter) ruptured, causing intra-abdominal hemorrhage and surgical hemostasis. There were thrombi in the ruptured varicosity and its draining vein. The likely cause was a pressure increase in the incompletely thrombosed varicosity due to shunt blood flow from the remaining shunts after embolization.

Radiation Exposure and Protection in Computed Tomography Fluoroscopy.

Computed tomography (CT) fluoroscopy-guided procedures, such as those used for percutaneous biopsy, drainage, and radiofrequency ablation, are highly safe and quite often very successful due to the precision offered by the real-time, high-resolution tomographic images. Even so, international guidelines raised concerns regarding operator exposure to high doses of radiation during these procedures. In light of these concerns, operators conducting CT fluoroscopy-guided procedures not only need to be cognizant of the exposure risk but also exhibit sufficient knowledge of radiation protection. This paper reviews the current literature on experimental and clinical studies of radiation exposure doses to operators during CT fluoroscopy-guided procedures. In addition to the literature review, this paper also introduces different approaches that can be implemented to ensure appropriate radiation protection.

Percutaneous Transsplenic Embolization of Gastric Varices in Left-sided Portal Hypertension.

An 81-year-old man with previously diagnosed cancer of the pancreatic body presented with melena and anemia. Upper gastrointestinal endoscopy showed gastric varices with bleeding in the entire stomach. Contrast-enhanced computed tomography identified a splenic vein occlusion resulting from invasion by the pancreatic body cancer and dilated collateral pathways from the splenic hilum to the gastric fundus. The patient was diagnosed with gastric varices associated with left-sided portal hypertension caused by obstruction of the splenic vein and underwent percutaneous transsplenic embolization with n-butyl-2-cyanoacrylate mixed with lipiodol. Splenic subcapsular hematoma occurred and was treated conservatively. The patient died of advanced cancer 5 months after the procedure, without experiencing rebleeding. Percutaneous transsplenic embolization was effective in treating gastric variceal bleeding caused by left-sided portal hypertension.

Practical Radiation Protection for Interventional Radiologist.

As per the International Commission on Radiological Protection 2010 recommendation, it was stated that "interventional radiologists performing difficult procedures with high workloads may be exposed to high doses" and that education and training of medical staffs in radiation exposure is "an urgent priority." There are many reports on the textbook aspects of radiation protection, but reports on the practical aspects of radiation protection have remained to be scarce. Various methods of reducing radiation exposure are described as "useful" or "can be reduced," but the priority of these methods and the "extent" to which they contribute to reducing radiation exposure are not clear. Thus, in this article, we will look into the protection of interventional radiologist from radiation exposure in a practical way, giving priority to clarity rather than academic accuracy.

A Case of Percutaneous Transesophageal Jejunostomy after Subtotal Esophagectomy.

An 80-year-old woman who underwent subtotal esophagectomy with gastric tube reconstruction for esophageal cancer developed carcinoma of the left upper gingiva. The local recurrence of the gingival carcinoma resulted in trismus and prevented oral intake. Then she underwent a percutaneous transesophageal jejunostomy tube placement in the preserved cervical esophagus. Enteral feeding continued for three months with no complications until oral intake was possible. A percutaneous transesophageal jejunostomy is possible using the postoperatively preserved cervical esophagus.

Evaluation of the antithrombogenicity of poly-2-methoxyethylacrylate-coated catheters.

BACKGROUND AND OBJECTIVES: The blood compatibility of indwelling intravascular catheters is facilitated by the use of antithrombogenic materials. Heparin has typically been used for this purpose; however, since heparin-coated catheters are considered combination products, difficulties meeting the relevant Food and Drug Administration safety recommendations have disrupted commercialization. Other issues include coating durability and the occurrence of heparin-induced thrombocytopenia. Polymer coatings are a potential alternative; however, polymer antithrombogenicity in circulating human blood has yet to be demonstrated. The present study aimed to establish the ex vivo antithrombogenicity of a poly-2-methoxyethylacrylate (PMEA) polymer coating applied to a central venous catheter using an artificial human blood circulation system. METHODS: The present study used an artificial human blood circulation system to conduct an ex vivo evaluation of the antithrombogenicity of poly-2-methoxyethylacrylate (PMEA)-coated catheters. Human blood samples obtained from volunteer donors were loaded into a circulation system fitted with either a PMEA-coated or uncoated catheter. After 3-h, the catheter was removed and examined using scanning electron microscopy. Protein adsorption on the catheter surface was investigated by shredding the catheter that had contacted the blood inside the circulation system and immersing the pieces in 1 mL of 0.5 N NaOH for 2 days. The amount of protein in the 0.5 N NaOH was determined according to the Lowry method. RESULTS: Adherent fibrin, which forms a sheath on the catheter surface, was observed on uncoated, but not PMEA-coated catheters. Furthermore, the amount of protein adsorption was significantly less with PMEA-coated than uncoated catheters (p = 0.043). CONCLUSIONS: The present findings demonstrated the antithrombogenicity of PMEA-coated catheters in circulating human blood.

Congenital pulmonary varix: Two case reports.

RATIONALE: Patients with congenital pulmonary varix are asymptomatic and require no treatment, but the radiological characteristics of a pulmonary varix are similar to those of a pulmonary arteriovenous malformation, which requires treatment. Pulmonary angiography is useful for obtaining information about the dynamics of pulmonary blood flow to differentiate a pulmonary varix from a pulmonary arteriovenous malformation for the purpose of treatment planning. Two cases of congenital pulmonary varices that were differentiated from pulmonary arteriovenous malformations based on pulmonary angiography findings are presented. PATIENT CONCERNS AND DIAGNOSIS: The first patient was an asymptomatic 39-year-old man. Non-contrast-enhanced computed tomography performed as part of the treatment course for pneumonia showed pulmonary arteriovenous malformation in the right lung. Pulmonary angiography was performed and showed that it was a pulmonary varix. The second patient was an asymptomatic 23-year-old woman. As part of her regular health check-up, she underwent plain chest X-ray examination, which showed an abnormal shadow. Non-contrast-enhanced computed tomography was performed, and pulmonary arteriovenous malformation was suspected. However, contrast-enhanced computed tomography findings suggested that the patient had a congenital pulmonary varix rather than a pulmonary arteriovenous malformation. Pulmonary angiography was subsequently performed for diagnosis, and a pulmonary varix was confirmed. INTERVENTIONS AND OUTCOMES: No treatment was administered to either patient. The first patient was followed up for four years, and the second patient for two years. Both patients had no symptoms or complications during the follow-up period. LESSONS: Two cases of congenital pulmonary varices were reported. Information about the dynamics of pulmonary blood flow obtained by performing pulmonary angiography was effective in distinguishing between pulmonary arteriovenous malformation and congenital pulmonary varix.

Subcapsular hepatic hematoma: a case of chronic expanding hematoma of the liver.

BACKGROUND: A chronic expanding hematoma (CEH) enlarges as a result of slight bleeding over several months, and the tissue shows a mixture of blood breakdown products, granulation tissue with capillary ingrowth, and inflammatory tissue. This report presents a case of a subcapsular hepatic CEH that was treated with transarterial embolization (TAE) and hepatectomy. CASE PRESENTATION: A 56-year-old man presented with vomiting and right-sided abdominal pain. Plain abdominal computed tomography (CT) showed a high-density area of fluid collection beneath the capsule of the right hepatic lobe, which was diagnosed as a hematoma. From its anatomical position on the CT images, a subcapsular hepatic hematoma was diagnosed. Though conservative therapy was provided, CT-guided percutaneous drainage and TAE were performed due to worsening symptom. Because the patient's abdominal symptoms re-appeared, extended right segmentectomy including the hematoma was performed. In the resected specimen, the hematoma was located beneath the capsule of the right hepatic lobe, and it was displacing the hepatic parenchyma. Microscopic examination showed a thick fibrous capsule around the hematoma, peripheral lymphocyte and plasmacyte invasion, and aggregations of histiocytes containing phagocytosed hemosiderin. CONCLUSIONS: Anatomically, this was a case of a subcapsular hepatic hematoma, and pathologically it was shown to be a CEH. Complete surgical resection was effective treatment for this CEH.

Clinical results of transarterial embolization for post-partum hemorrhage in 62 patients.

AIM: The pathology of post-partum hemorrhage (PPH) differs depending on its cause, background and timing of bleeding, and the effectiveness of transarterial embolization (TAE) is thought to vary based on these characteristics. The aim of this study is to evaluate the treatment outcomes of TAE for PPH. METHODS: Technical success, initial clinical success (hemostasis without repeat TAE or surgical treatment after initial TAE) and final clinical success (hemostasis with or without repeat TAE, but without surgical treatment) were assessed in 62 Japanese patients. Factors affecting final clinical success were analyzed using univariate analysis. Values of P < 0.05 were considered statistically significant. Further, the clinical course and factors associated with rebleeding, return of menstruation and fertility, and complications of TAE were assessed. RESULTS: Final clinical success rate was significantly lower in cases with obstetrical disseminated intravascular coagulation (DIC) or the International Society on Thrombosis and Hemostasis (ISTH) DIC (P = 0.01, 0.03). Rebleeding (n = 9, 14.5%) was more common in patients with retained products of conception (RPOC) (P = 0.006). On long-term follow-up in 23 patients, return of menstruation was confirmed in 17 (73.9%) of these patients. Subsequent pregnancy was confirmed in seven patients (30.4%). TAE-related complications were seen in 6 patients (9.0%). There were no maternal deaths. CONCLUSIONS: Obstetrical and ISTH DIC reduced the success rate of TAE for PPH (P = 0.01, 0.03). Rebleeding, which is observed significantly more frequently in PPH caused by RPOC (P = 0.006), can be effectively treated by repeat TAE.

Assessment of the Antithrombogenicity of a Poly-2-Methoxyethylacrylate-Coated Central Venous Port-Catheter System.

PURPOSE: The purpose of this study was to evaluate the antithrombogenic effects of poly-2-methoxyethylacrylate (PMEA) coating applied to the internal surfaces of the port-catheter system to prevent thrombotic occlusion. MATERIALS AND METHODS: PMEA coating was applied to the inner surfaces of the entire system, including the chamber, catheter, and connecting stem. PMEA-coated and uncoated port-catheter systems were each filled with fresh human blood for 1 or 3 h and then flushed with saline. Volumes of residual thrombi in the system and protein in the catheter were then compared. RESULTS: Saline flushing of the PMEA-coated port-catheter system expelled all visually recognizable thrombi, leaving no unremovable adhesions. In contrast, the uncoated port showed thrombi adherent to the inner surfaces and incomplete expulsion with flushing. Mean (± standard deviation) residual thrombus mass was significantly lower in PMEA-coated port-catheter systems (20.5 ± 6.2 mg) than in uncoated systems (230.3 ± 92.5 mg; p < 0.01). Mean residual protein was likewise significantly lower in PMEA-coated systems (20.5 ± 6.2 mg) than in uncoated systems (230.3 ± 92.5 mg; p < 0.01). CONCLUSIONS: PMEA coating on a central venous port-catheter system decreased accumulation and facilitated flushing of thrombi from the system by flushing, as compared with the uncoated system. PMEA-coated central venous port-catheter systems appear relatively antithrombotic compared to uncoated systems.

Simultaneous Drainage of the Abscess Cavity and Intestinal Tract for an Intra-abdominal Abscess Secondary to Major Leakage: A Case Report.

This case report describes a 72-year-old man who developed an intra-abdominal abscess and major postoperative anastomotic leakage. He reported a history of pancreaticoduodenectomy, partial hepatectomy, and segmental colectomy for hepatic and colonic invasion of extrahepatic cholangiocarcinoma. Three catheters, (one in the transverse colon and two in the abscess cavity) were placed simultaneously through the drainage tract formed by the intraoperatively placed Pleats drain. The intra-abdominal abscess resolved following this intervention and has not recurred since. Postoperative drainage and starvation were continued for 52 and 84 days, respectively. This case report describes a novel technique of catheter insertion from the abscess cavity into the intestine through the site of rupture to reduce intestinal pressure and partially block the enteric fistula.

Provocative angiography for lower gastrointestinal bleeding.

PURPOSE: This study evaluated the results of provocative angiography performed to identify the site of hemorrhage in lower gastrointestinal bleeding to enable transcatheter arterial embolization. MATERIALS AND METHODS: The subjects of this study were 11 patients with acute lower gastrointestinal bleeding who underwent provocative angiography, after contrast agent extravasation could not be identified during conventional angiography. One patient underwent provocative angiography twice, making 12 cases of provocative angiography that were analyzed in this study. Urokinase was used in all cases. Heparin was administered in 2 cases, nicardipine in 3 cases, and alprostadil and isosorbide in 1 case each. RESULTS: Contrast agent extravasation as a result of provocative angiography was observed in 6/12 cases (50%). Selective transcatheter arterial embolization was performed in all 6 cases in which extravasation was apparent, and it was technically successful in all six. Clinical success was achieved in 5 (83.3%) of the 6 cases in which technical success was achieved after provocative angiography. CONCLUSION: Provocative angiography enabled the site of lower gastrointestinal bleeding to be identified in 6 of 12 cases (50.0%) when it could not be identified by conventional angiography, and in all 6 cases hemostasis was effectively achieved by embolization.

Percutaneous Balloon Plasty for Thoracic Duct Occlusion in a Patient with Chylothorax and Chylous Ascites.

A patient developed abdominal distension, dyspnea, and nausea due to chylothorax and chylous ascites 1 month after bruising her back. Lymphangiography was unable to identify the site of lymph leakage, and lymphatic duct embolization was impractical. However, lymphangiography showed occlusion of the thoracic duct. Thus, balloon plasty was performed to restore the patency of the thoracic duct, and the chylothorax and chylous ascites improved. Although embolization of the thoracic or lymphatic ducts has been reported as a treatment for lymphorrhea, it is impractical if the lymphatic duct responsible for leakage cannot be identified. In such a case, balloon plasty of the occluded thoracic duct to lower the pressure in the peripheral lymphatic ducts was successfully performed.

Central venous access port placement by translumbar approach using angio-CT unit in patients with superior vena cava syndrome.

PURPOSE: To evaluate the clinical results of central venous access port (CV port) placement by translumbar inferior vena cava cannulation using angio-CT unit for cancer patients with superior vena cava syndrome. MATERIALS AND METHODS: A CV port was placed by translumbar inferior vena cava cannulation using an angio-CT unit, in 14 consecutive patients. All patients had occlusion or advanced stenosis of the superior vena cava due to cancer progression. RESULTS: The technical success rate of the percutaneous translumbar CV port placement was 100%. The only complication related to port placement was bleeding in the right iliopsoas muscle seen on CT in one patient, but it stopped with conservative treatment. The mean initial device service interval was 125 days (range 6-448 days). Complications in the chronic phase occurred in two patients, one with catheter-related infection and the other with catheter breakage, for a rate of 0.44/1000 catheter days. In the patient with the broken catheter, the port chamber placement site was cut and replaced with a new catheter by guidewire exchange. CONCLUSIONS: CV port placement with translumbar inferior vena cava cannulation using an angio-CT unit for cancer patients with superior vena cava syndrome was safe and effective.

Transvenous Retrograde Thoracic Ductography: Initial Experience with 13 Consecutive Cases.

PURPOSE: To report the feasibility and findings of transvenous retrograde thoracic duct cannulation. MATERIALS AND METHODS: The subjects were 13 patients who had undergone retrograde transvenous thoracic ductography. Despite conservative treatment, all required drainage for chylothorax, chylous ascites, or a chylous pericardial effusion. Lymphangiography was performed, and the junction of the thoracic duct with the vein was identified. A microcatheter was inserted into the thoracic duct retrogradely via the junction with the vein. RESULTS: The catheter could be inserted to the cervical part, thoracic part, and cisterna chyli in 12 (92.3%), nine (69.2%), and six (46.2%) patients, respectively. Successful transvenous thoracic ductography was performed in eight patients (61.5%). The cervical part of the thoracic duct was branched into a plexiform configuration beyond which the microcatheter could not be advanced to reach the thoracic part in three unsuccessful cases. The success rate of transvenous thoracic ductography was significantly higher with the simple type (80%) than with the plexiform type (0%; p = 0.035). No extravasation of contrast agent was seen in the eight patients with successful thoracic ductography. Thoracic duct embolization was performed in one patient with a chylous pericardial effusion in whom myriad lymph ducts connecting to the hilar and pericardial regions from the thoracic duct were found, and drainage was unnecessary. CONCLUSION: Transvenous retrograde thoracic ductography was successful in only eight of 13 patients (61.5%), but when the cervical part was the simple type, it was successful in eight of 10 patients (80%).

Sclerotherapy for Rectal Varices by a Small-Bore Needle Puncture Through the Greater Sciatic Foramen.

PURPOSE: To report a sclerotherapy technique for rectal varices consisting of direct puncture of the superior rectal vein with a small-bore sheathed needle via the greater sciatic foramen without insertion of a sheath or catheter. MATERIALS AND METHODS: The subjects of this retrospective study were three consecutive patients who underwent embolization of rectal varices, two for rupture of rectal varices and one for hepatic encephalopathy and hyperammonemia. A 5% solution of ethanolamine oleate with iodinated contrast agent (5% EOI) was injected through puncture of the superior rectal vein and carried in the blood flow, after which n-butyl cyanoacrylate mixed with lipiodol (NBCA-Lip) was immediately injected to stop the blood flow. RESULTS: The 5% EOI and NBCA-Lip were successfully injected in all three patients. There was no movement of NBCA-Lip on plain radiographs or computed tomography (CT) immediately after injection, and the 5% EOI remained within the rectal varices. The mean procedure time was 53 min (42-60 min). On contrast-enhanced CT 1 month after the procedure, there was no contrast enhancement of the rectal varices that had been seen on preoperative CT in any of the three patients, confirming that the rectal varices had disappeared. CONCLUSION: Sclerotherapy for rectal varices using an approach for puncture of the superior rectal vein with a small-bore sheathed needle via the greater sciatic foramen was technically feasible and clinically effective.