The Impact of Sorafenib in Combination with Intermittent Hepatic Arterial Infusion Chemotherapy for Unresectable Hepatocellular Carcinoma with Major Vascular Invasion.

The aim of the current study was to investigate the efficacy and safety of sorafenib and intermittent hepatic arterial infusion chemotherapy with cisplatin for unresectable hepatocellular carcinoma (HCC) with severe portal vein invasion. The antitumor effect was a complete response in 1 of 38 patients, a partial response in 12 patients, stable disease in 16 patients, and progressive disease in 9 patients, for a 34.2% response rate and a 76.3% disease control rate. This regimen had favorable efficacy and acceptable safety and may be feasible for unresectable HCC with severe portal vein invasion.

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.

Scaffold protein enigma homolog 1 overcomes the repression of myogenesis activation by inhibitor of DNA binding 2.

Enigma Homolog 1 (ENH1) is a scaffold protein for signaling proteins and transcription factors. Previously, we reported that ENH1 overexpression promotes the differentiation of C2C12 myoblasts. However, the molecular mechanism underlying the role of ENH1 in the C2C12 cells differentiation remains elusive. ENH1 was shown to inhibit the proliferation of neuroblastoma cells by sequestering Inhibitor of DNA binding protein 2 (Id2) in the cytosol. Id2 is a repressor of basic Helix-Loop-Helix transcription factors activity and prevents myogenesis. Here, we found that ENH1 overcome the Id2 repression of C2C12 cells myogenic differentiation and that ENH1 overexpression promotes mice satellite cells activation, the first step toward myogenic differentiation. In addition, we show that ENH1 interacted with Id2 in C2C12 cells and mice satellite cells. Collectively, our results suggest that ENH1 plays an important role in the activation of myogenesis through the repression of Id2 activity.

Validity of muscle thickness-based prediction equation for quadriceps femoris volume in middle-aged and older men and women.

BACKGROUND: This study examined the validity of muscle thickness (MT)-based prediction equation for the muscle volume of the quadriceps femoris (QFMV) by evaluating the applicability of a prediction equation previously derived from young men and by developing a new prediction equation in middle-aged and older individuals. METHODS: The MT at the midpoint of the thigh anterior and QFMV were determined using ultrasonography and magnetic resonance imaging in 30 men and 30 women aged 51 to 77 years. First, we examined the validity of the MT-based prediction equation previously developed for young men to estimate the QFMV of middle-aged and older individuals. Second, we allocated the subjects to validation or cross-validation group and developed a prediction equation for estimating the QFMV using a stepwise multiple regression analysis. RESULTS: The published equation generated a small but a significant difference between the measured and estimated QFMV, with a systematic error depending on the size of QFMV. A multiple regression analysis for the validation group produced the following equation: QFMV (cm3) = (sex × 267.7) + (MT × 249.3) + (thigh length × 41.1) - 1663.7 (sex: man = 1, woman = 0). R 2 and SEE of the regression equation were 0.888 and 124.4 cm3 (12.0 %), respectively. The developed equation was validated and cross-validated. CONCLUSION: For middle-aged and older individuals, the prediction equation previously derived from young men is not applicable, and the newly developed prediction equation with sex, MT, and thigh length as independent variables is applicable for estimating QFMV.

Relationships of ultrasound measures of intrinsic foot muscle cross-sectional area and muscle volume with maximum toe flexor muscle strength and physical performance in young adults.

[Purpose] To investigate the relationships between toe flexor muscle strength with (TFS-5-toes) and without (TFS-4-toes) the contribution of the great toe, anatomical and physiological muscle cross-sectional areas (CSA) of intrinsic toe flexor muscle and physical performance were measured. [Subjects] Seventeen men (82% sports-active) and 17 women (47% sports-active), aged 20 to 35 years, volunteered. [Methods] Anatomical CSA was measured in two intrinsic toe flexor muscles (flexor digitorum brevis [FDB] and abductor hallucis) by ultrasound. Muscle volume and muscle length of the FDB were also estimated, and physiological CSA was calculated. [Results] Both TFS-5-toes and TFS-4-toes correlated positively with walking speed in men (r=0.584 and r=0.553, respectively) and women (r=0.748 and r=0.533, respectively). Physiological CSA of the FDB was significantly correlated with TFS-5-toes (r=0.748) and TFS-4-toes (r=0.573) in women. In men, physiological CSA of the FDB correlated positively with TFS-4-toes (r=0.536), but not with TFS-5-toes (r=0.333). [Conclusion] Our results indicate that physiological CSA of the FDB is moderately associated with TFS-4-toes while toe flexor strength correlates with walking performance.

Evaluation of an aspiration-type semiautomatic cutting biopsy needle.

PURPOSE: The purpose of this study was to evaluate an aspiration-type semiautomatic cutting biopsy needle for biopsy of bovine tissue. MATERIAL AND METHODS: Aspiration-type semiautomatic cutting biopsy needles (18 gauge × 160 mm) with aspiration (Group A), aspiration-type semiautomatic biopsy needles without aspiration (Group Wo), or normal-type semiautomatic biopsy needles (18 gauge × 150 mm) (Group N) were used in 10 biopsies each of bovine liver or lung. The specimens were weighed with an electronic balance. RESULTS: Mean (standard deviation) weights for bovine liver specimens in Groups A, Wo, and N were 6.80 (0.615) mg, 5.62 (0.843) mg, and 4.19 (0.140) mg, respectively. Mean weights of bovine lung specimens from Groups A, Wo, and N were 2.98 (0.828) mg, 2.67 (0.832) mg, and 1.94 (0.864) mg, respectively. A significant difference was seen between the 3 groups for bovine liver. However, a significant difference was only seen between Groups A and N for bovine lung. CONCLUSION: Bovine liver and lung specimens obtained using the aspiration-type semiautomatic cutting biopsy needle were heavier than those obtained using the normal-type semiautomatic biopsy needle.

[Feasibility and Safety of Dexmedetomidine Sedation in Transarterial Embolization for Hepatocellular Carcinoma with Hepatitis C-Related Cirrhosis].

BACKGROUND: Dexmedetomidine (Precedex®)is an agonist of a2-adrenergic receptors in certain parts of the brain. It was approved for "procedural sedation in the non-intubation in under local anesthesia" in June 2013 in Japan. However, because of metabolism delay, dexmedetomidine has to be administered carefully to patients with liver dysfunction. PURPOSE: To evaluate the feasibility and safety of sedation using dexmedetomidine in percutaneous arterial chemoembolization for hepatocellular carcinoma with liver dysfunction. METHODS: Thirty consecutive cases of percutaneous arterial chemoembolization for hepatocellular carcinoma with hepatitis C-related cirrhosis(male, 23; female, 7; age, 74±5.9; weight, 62.7±12.3 kg; Child-Pugh A, 23; Child-Pugh B, 7)were analyzed retrospectively. Dexmedetomidine was administered at 3 mg/kg/h for 15 minutes as the initial loading dose and at 0.4 mg/kg/h as the maintenance dose. The sedation level was evaluated using the Ramsay sedation scale. RESULTS: In 30 of 30 cases, percutaneous arterial chemoembolization therapy could be performed with dexme- detomidine sedation. In 27 of 30 cases, the procedure was completed with the maintenance dose of 0.4 mg/kg/h. In 3 of 30 cases, the maintenance dose was increased to 0.6 mg/kg/h because of patient body motion. The mean administration time of dexmedetomidine was 82±30 minutes. The level of sedation measured with the Ramsay sedation scale at the end of the procedure was 3 points in 29 cases and 5 points in one case. Adverse events occurred in 3 of 30 cases. Intravenous drip leakage occurred in one case, vertigo occurred in one case, and vomiting occurred in one case. There were no adverse events requiring treatment. CONCLUSION: Sedation with dexmedetomidine in percutaneous arterial chemoembolization for hepatocellular carcinoma with liver dysfunction was feasible and safe.

Radiation dose of nurses during IR procedures: a controlled trial evaluating operator alerts before nursing tasks.

PURPOSE: To compare radiation exposure of nurses when performing nursing tasks associated with interventional procedures depending on whether or not the nurses called out to the operator before approaching the patient. MATERIALS AND METHODS: In a prospective study, 93 interventional radiology procedures were randomly divided into a call group and a no-call group; there were 50 procedures in the call group and 43 procedures in the no-call group. Two monitoring badges were used to calculate effective dose of nurses. In the call group, the nurse first told the operator she was going to approach the patient each time she was about to do so. In the no-call group, the nurse did not say anything to the operator when she was about to approach the patient. RESULTS: In all the nursing tasks, the equivalent dose at the umbilical level inside the lead apron was below the detectable limit. The equivalent dose at the sternal level outside the lead apron was 0.16 µSv ± 0.41 per procedure in the call group and 0.51 µSv ± 1.17 per procedure in the no-call group. The effective dose was 0.018 µSv ± 0.04 per procedure in the call group and 0.056 µSv ± 0.129 per procedure in the no-call group. The call group had a significantly lower radiation dose (P = .034). CONCLUSIONS: Radiation doses of nurses were lower in the group in which the nurse called to the operator before she approached the patient.

Portopulmonary venous anastomosis in balloon-occluded retrograde transvenous obliteration for the treatment of gastric varices.

BACKGROUND AND AIM: Several reports have described portopulmonary venous anastomosis (PPVA). However, in balloon-occluded retrograde transvenous obliteration (BRTO), attention has not been paid to paradoxical embolism. The objective of this study was to investigate the existence of a right-left shunt due to PPVA when the drainage vein is occluded by a balloon during BRTO. METHODS: The subjects were 19 patients who underwent BRTO. Whether PPVA was present was confirmed on balloon-occluded retrograde transvenous venography (BRTV). After BRTV, a retrograde bolus injection of 20 mL of carbon dioxide (CO2 ) via the balloon catheter was performed under balloon occlusion, and the flow of bubbles into both ventricles was observed with four-chamber view echocardiography. During the same balloon occlusion, bolus injection of CO2 into the inferior vena cava was performed, followed by echocardiography. RESULTS: PPVA was confirmed on BRTV in four patients (21.1%). On echocardiography with retrograde CO2 injection, bubbles were confirmed in the left ventricle in six patients (31.6%). On echocardiography with CO2 injection into the inferior vena cava, bubbles were not confirmed in the left ventricle in any cases. CONCLUSIONS: When the draining vein was occluded with a balloon and blood flow in a gastrorenal or gastrocaval shunt was stopped during BRTO, PPVA was confirmed in 21.1% of cases on retrograde angiography, and a right-left shunt was confirmed in 31.6% of cases on echocardiography.

Direct puncture embolization using N-butyl cyanoacrylate for a hepatic artery pseudoaneurysm.

Massive hemobilia caused by hepatic artery pseudoaneurysm is an uncommon but potentially fatal complication that can occur after biliary intervention. Previous intervention or surgery, atherosclerotic disease, inflammation and even anatomic variants may make the pseudoaneurysm inaccessible to transcatheter approach, therefore it is not always feasible. The present report describes a case of successful embolization of a hepatic artery pseudoaneurysm with N-butyl cyanoacrylate via direct puncture as an alternative approach. The case presentation is followed by the technical points and the properties of N-butyl cyanoacrylate that are particularly advantageous for use in direct puncture procedures.

Comparison of Tc-99m GSA scintigraphy and CT volumetry for evaluation in portal vein embolization.

PURPOSE: To determine the correlation of the rate of change of each future remnant liver (FRL) before and after portal vein embolization (PVE), by CT volumetry and Tc-99m galactosyl human serum albumin scintigraphy (GSA scintigraphy). MATERIAL AND METHODS: From December 2007 to July 2012, ten patients underwent PVE before hepatic resection. CT volumetry and GSA scintigraphy were performed before and after PVE. The FRL was divided at Cantlie's line for CT volumetry, and volume change rates before and after PVE were calculated. The maximum removal rate (Rmax) was calculated using a radiopharmacokinetic model in GSA scintigraphy. The FRL Rmax change rates before and after PVE were calculated. The correlation between the volume change rates and the Rmax change rates was analyzed. RESULTS: The FRL volume change rate was 1.28 ± 0.26 (mean ± SD); the FRL hypertrophied in all patients significantly (p = 0.005). The FRL Rmax change rate was 1.66 ± 0.75; excluding one patient, there was significant FRL Rmax increase (p = 0.022). Although both increased significantly, no correlation between the volume change rate and the Rmax change rate was observed. CONCLUSION: No correlation was observed between the FRL volume rate and the Rmax rate.

Intra-arterial infusion of thrombin: animal experiments.

PURPOSE: Thrombin inhibits cadherin on vascular endothelial cells, rapidly and reversibly increasing endothelial permeability. The purpose of this study was to evaluate the feasibility of trans-arterial infusion with thrombin. MATERIAL AND METHODS: Ten rabbits with right thigh tumor were randomly divided into two groups: A thrombin group and a control group. In the thrombin group, a suspension of thrombin (300 IU), cisplatin (3 mg), lipiodol (0.3 ml) and iopamidol (0.3 ml) was infused into the right femoral artery. In the control group, a suspension of cisplatin, lipiodol and iopamidol was infused. Platinum concentrations in plasma were measured five and ten minutes after administration. Platinum concentrations were also measured in tumor specimens excised 30 minutes after infusion. RESULTS: At both five and ten minutes after infusion, platinum concentrations in plasma were significantly lower for the thrombin group than for the control group. Platinum concentration in tumor tissue was significantly higher for the thrombin group than for the control group. CONCLUSION: The present results suggest that transarterial infusion with thrombin may offer a number of pharmacological advantages.

Effects of Different Isometric Training Programs on Muscle Size and Function in the Elbow Flexors.

It remains unknown whether a regimen of a combination of high- and low-intensity resistance training increases muscle size and maximal voluntary isometric contraction (MVC) simultaneously. This study aimed to clarify the effect of the combination of high- and low-intensity resistance training on muscle size and neuromuscular function in the elbow flexors. Sixteen male adults participated in a 9-week isometric training regimen in elbow joint flexion of each arm. We randomly assigned two different training regimens to left and right arms: one aiming to strengthen maximal strength (ST) and the other aiming to develop muscle size as well as maximal strength, which consists of one contraction to volitional failure with 50% of MVC added to ST (COMB). Following the 3-week training to volitional failure as familiarization, the participants conducted the 6-week ST and COMB training in each arm. Before the intervention, and at the third (Mid) and ninth (Post) weeks, MVC and muscle thickness in the anterior part of the upper arm (ultrasound) were measured. Muscle cross-sectional area (mCSA) was derived from the obtained muscle thickness. From Mid to Post, the relative change in MVC was similar in both arms. The COMB regimen increased muscle size, but no significant change was found in ST. Following the 3-week isometric training to volitional failure, the 6-week training regimen for developing maximal voluntary and muscle hypertrophy increased MVC, with increasing mCSA, and the training-induced change in MVC was similar to that for developing maximal voluntary strength alone.

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.

Added value of percutaneous vertebroplasty: effects on respiratory function.

OBJECTIVE: The objective of our study was to investigate the effects of percutaneous vertebroplasty on respiratory function in patients with compression fractures caused by osteoporosis. SUBJECTS AND METHODS: Ninety-eight patients (87 women, 11 men; mean age, 74 years; age range, 60-90 years) with compression fractures of 75 thoracic (Th7-Th12) and 89 lumbar (L1-L5) vertebrae were enrolled in this study. Percentage vital capacity (VC%), percentage forced vital capacity (FVC%), and percentage forced expiratory volume in 1 second (%FEV1) were measured using a spirometer before, 1 day after, and 1 month after percutaneous vertebroplasty. The Wilcoxon signed rank test was used to evaluate whether any significant differences in VC%, FVC%, or %FEV1 values existed between before, 1 day after, and 1 month after percutaneous vertebroplasty. RESULTS: The VC% and FVC% values had improved significantly by 1 month after percutaneous vertebroplasty compared with before percutaneous vertebroplasty (p<0.01). No significant difference was noted between values before and 1 day after percutaneous vertebroplasty. Likewise, no significant difference was identified in %FEV1 before percutaneous vertebroplasty and either 1 day or 1 month after percutaneous vertebroplasty. The mean degree of improvement in VC% values after percutaneous vertebroplasty for patients with one vertebra treated, which we refer to as the "single-vertebroplasty" group, and for patients with two or more vertebrae treated, or "multiple-vertebroplasty" group, was 1.1%±7% (SD) and 6.3%±8%, respectively, representing a significant difference between groups (p=0.01). The mean VC% values before and 1 month after percutaneous vertebroplasty differed significantly (p=0.02) in the thoracic group and overlapping group. CONCLUSION: Percutaneous vertebroplasty improves restrictive ventilatory impairment, but this improvement requires approximately 1 month to occur. Greater improvement in restrictive ventilatory dysfunction was observed in patients who underwent multiple vertebroplasty procedures than those who underwent a single procedure and in patients who underwent treatment of thoracic vertebrae than those who underwent treatment of other vertebrae.

Analysis of factors influencing accuracy and complications in CT-guided lung biopsy.

INTRODUCTION: This study aimed to analyze factors influencing accuracy and complications in patients who underwent computed tomography (CT)-guided lung biopsy at our medical center. MATERIAL AND METHODS: This study included all 107 patients (72 men, 35 women; mean age, 69 years; range, 41-83 years) who underwent CT-guided lung biopsy between January 2006 and October 2009. CT fluoroscopy was used in 45.7% of cases. Final diagnosis, when surgical resection was performed, was histopathological diagnosis from the lung lesion specimen, and when resection was not performed, clinical diagnosis after ≥6 months of follow-up. The accuracy of lung biopsy was assessed by comparison of biopsy results and final diagnosis. The influence of factors on accuracy was statistically analyzed. RESULTS: Accuracy of CT-guided lung biopsy was 89.4%. None of the factors, including lesion size, lesion depth from pleura, lesion location, patient position, final diagnosis, and use or non-use of CT fluoroscopy, had any significant influence on accuracy. The only complications were Grade 1 and 2 pneumothorax and Grade 1 pulmonary bleeding. The incidence of pneumothorax and bleeding was significantly increased with smaller lesion size and significantly increased with greater lesion depth. In patients with pulmonary emphysema, bleeding was significantly less (p = 0.022). When CT fluoroscopy was used, bleeding was significantly increased (p < 0.001). CONCLUSIONS: None of the factors had any significant influence on accuracy. The incidence of pneumothorax and bleeding was affected by lesion size and lesion depth. When CT fluoroscopy was used, bleeding was significantly increased.

Metallic stent placement for malignant airway stenosis.

The purpose of this study was to evaluate the utility of metallic stents for treating central airway stenosis caused by malignant tumors. The subjects were 72 patients (16 women, 56 men; mean age, 61 years; age range, 28-87 years) treated with metallic stents for dyspnea due to tracheobronchial stenotic lesions caused by malignant tumors between May 1990 and August 2010. The underlying disorder was primary lung cancer in 42 patients, metastatic lung cancer in 29, and mediastinal tumor in one patient. In 69 of 72 patients (95.8%), dyspnea began to improve following completion of the procedure. The average Hugh-Jones classification score improved from 4.2 before stenting to 2.8 after stenting. The patients' average survival following stent placement was 3.6 months (two days-33 months). Thirteen lesions developed re-obstruction during follow-up. Of these 13 lesions, eight patients with dyspnea underwent re-interventions with metallic stent replacement and improved. Airway stent placement is an immediate and effective method of treatment for dyspnea caused by stenotic lesions of the central airway due to malignant tumor. It is effective for treating stenosis due to either tracheobronchial intraluminal tumor or extrinsic compression. Restenting is also useful to treat dyspnea caused by restenosis following stent placement.

Percutaneous bypass creation between hollow organs by modified gun-sight approach.

This animal study investigated the feasibility of creating a bypass between two hollow organs, using a modified gun-sight approach with a pull-through string and pull-through tow wire. Ten procedures (femoral arteriovenous shunt, n = 4; portacaval shunt, n = 4; cholangiogastrostomy, n = 2) were performed in six adult swine. Snares were inserted into the two hollow organs through the sheath and deployed at the site of bypass creation. When snares overlapped on fluoroscopy, a needle was inserted to pass through both snares. The string was inserted through the needle, with only the needle then withdrawn. The snare furthest from the skin was closed to capture the string and was then withdrawn. The other snare was withdrawn without closing. The string thus served as a pull-through string penetrating both hollow organs. This string was then attached to a pull-through tow wire, withdrawn, and exchanged for the pull-through tow wire. By withdrawing the pull-through tow wire, the delivery sheath connected to the pull-through tow wire was towed through the site of the bypass, and the stent was placed. In all cases, bypass creation was achieved. Percutaneous bypass creation using a modified gun-sight approach with a pull-through string and pull-through tow wire is feasible between two hollow organs.

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.