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Purpose: To examine the characteristics of drug-loaded superabsorbent polymer microspheres (SAP-MS) such as drug absorption, drug release, diameter, and visibility. Materials and Methods: SAP-MS (HepaSphere150–200 µm; Merit Medical, South Jordan, UT, USA) were suspended in drug solutions: (a) cefazolin, (b) lidocaine, (c) iopamidol and cefazolin, (d) iopamidol and lidocaine, and (e) iopamidol, cefazolin, and lidocaine. The concentrations of drugs were measured, and the amount of each drug absorbed was calculated. Filtered drug-loaded SAP-MS were mixed with saline, and the drug release rates were calculated. The diameter changes of SAP-MS during absorption were observed. Radiography of drug-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio (CNR). Results: The drug concentration did not change during absorption. The release rates increased for 10 min and then came to an equilibrium. The mean amounts of drug absorbed at 180 min and mean release rates at 24 h were (a) cefazolin: 265.4 mg, 64.2%; (b) lidocaine: 19.6 mg, 75.6%; (c) iopamidol: 830.2 mg, 22.5%; cefazolin: 137.6 mg, 21.2%; (d) iopamidol: 1620.6 mg, 78.5%; lidocaine: 13.5 mg, 81.4%; and (e) iopamidol: 643.7 mg, 52.9%; cefazolin: 194.0 mg, 51.6%; lidocaine: 5.3 mg, 58.4%. The diameter of SAP-MS increased for approximately 15 min. Finally, the diameters of SAP-MS were (a) 3.9 times, (b) 5.0 times, (c) 2.2 times, (d) 5.5 times, and (e) 3.6 times larger than the original size. Drug-loaded SAP-MS containing iopamidol were visible under X-ray imaging, with CNRs of (c) 3.0, (d) 9.0, and (e) 4.5. Conclusion: SAP-MS can absorb and release iopamidol, cefazolin, and lidocaine. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess the diagnostic accuracy of computed tomography (CT) and time-resolved magnetic resonance angiography (TR-MRA) for patency after coil embolization of pulmonary arteriovenous malformations (PAVMs) and identify factors affecting patency.Methods: Data from the records of 205 patients with 378 untreated PAVMs were retrospectively analyzed. Differences in proportional reduction of the sac or draining vein on CT between occluded and patent PAVMs were examined, and receiver operating characteristic analysis was performed to assess the accuracy of CT using digital subtraction angiography (DSA) as the definitive diagnostic modality. The accuracy of TR-MRA was also assessed in comparison to DSA. Potential factors affecting patency, including sex, age, number of PAVMs, location of PAVMs, type of PAVM, and location of embolization, were evaluated.Results: The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CT were 82%, 81%, 77%, 85%, and 82%, respectively, when the reduction rate threshold was set to 55%, which led to the highest diagnostic accuracy. The sensitivity, specificity, PPV, NPV, and accuracy of TR-MRA were 89%, 95%, 89%, 95%, and 93%, respectively. On both univariable and multivariable analyses, embolization of the distal position to the last normal branch of the pulmonary artery was a factor that significantly affected the prevention of patency.Conclusions: TR-MRA appears to be an appropriate method for follow-up examinations due to its high accuracy for the diagnosis of patency after coil embolization of PAVMs. The location of embolization is a factor affecting patency.Key Points: • Diagnosis of patency after coil embolization for pulmonary arteriovenous malformations (PAVMs) is important because a patent PAVM can lead to neurologic complications. • The diagnostic accuracies of CT with a cutoff value of 55% and TR-MRA were 82% and 93%, respectively. • The positioning of the coils relative to the sac and the last normal branch of the artery was significant for preventing PAVM patency. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) under X-ray imaging.Materials and Methods: SAP-MS were suspended in contrast material (iodixanol) and the diameter change was assessed. The diameter of contrast-loaded SAP-MS in saline was measured sequentially. Radiography of the contrast-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio and visibility by multiple reader scoring. Under digital subtraction angiography, contrast-loaded SAP-MS were injected into a flow model. The flow speed was 1-10 cm/s, and images were acquired at 1-7.5 frames per second using a pulse width of 10-85 ms. Images were assessed by multiple reader scoring.Results: The diameter of SAP-MS increased to 4.0-5.0 times its original size for approximately 15 min. The diameter of contrast-loaded SAP-MS in saline further increased by 10-30% within several minutes and returned to the previous size. Radiopacity and visibility of contrast-loaded SAP-MS decreased in 30 min after mixing with saline. Visibility was better with slow flow speed and narrow pulse width.Conclusion: For effective observation, contrast-loaded SAP-MS should be kept in non-diluted contrast material until use. The conditions of slower flow and use of a narrow pulse width are recommended. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the embolic effect and the safety of transarterial embolization (TAE) using n-butyl-2-cyanoacrylate (NBCA) in a prospective multicenter trial.Materials and Methods: This study was an open-label, multicenter, phase II trial. The inclusion criteria were (1) active bleeding or pseudoaneurysm, (2) true aneurysm, (3) arteriovenous malformation (except cerebral lesion), (4) arteriovenous fistula, or (5) need for arterial distribution before transarterial treatment. Selective TAE with NBCA diluted 2-10 times was performed. The primary endpoint was the success rate of embolization with a per-patient analysis based on the angiographic findings. Secondary endpoints were safety, evaluated based on Common Terminology Criteria for Adverse Events (CTCAE) version 4, and the success rate of embolization with a per-vessel calculation.Results: Sixty-five patients were initially enrolled, but due to protocol violation in two patients, efficacy was ultimately analyzed in 63 patients (103 vessels) and safety was analyzed in 64 patients. The success rate per patient was 98.4% (62/63; 95% confidence interval (CI), 91.5-100.00), and the success rate per vessel was 99.0% (102/103; 95% CI, 94.7-100.0). Adverse events of grade 3 or above based on CTCAE version 4 occurred in 22/64 patients (34.4%). Twelve intraoperative or postoperative adverse events grade 3 or above, which may have been related to embolization using NBCA, occurred in 11/64 patients (17.2%). Three patients died after embolization using NBCA, but their deaths were unrelated to TAE.Conclusion: In this prospective multicenter clinical trial, the efficacy of TAE using NBCA was 98.4% and adverse events were clinically acceptable.Level Of Evidence: Level 3b. [ABSTRACT FROM AUTHOR]

Purpose: To assess the safety and effectiveness of polidocanol sclerotherapy combined with transarterial embolization using a liquid adhesive agent (n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs).Materials and Methods: Twenty-three patients with symptomatic AVMs in the head and neck (6), upper (7) and lower extremity (10) with a mean age of 42 years (range 4-74) treated with polidocanol sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 2 type I, 6 type II, 6 type IIIa and 9 type IIIb. Arterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. Polidocanol mixed with contrast material or carbon dioxide was delivered by percutaneous direct puncture.Results: Treatment was successfully performed in all patients. In the mean follow-up period of 38 months, symptoms resolved or improved in 20/23 patients (87.0%). AVMs were devascularized 100% in 2 patients, 76-99% in 13, 50-75% in 7 and < 50% in 1. More than 50% devascularization was seen in 22 patients (95.6%). Two (8%) patients had complete remission, 17 (74%) had partial remission and 3 (13%) had no remission. There was no aggravation. Treatment was considered effective (complete and partial remission) in 20 patients (87.0%). Minor complications including localized arterial thrombosis (2) and spontaneously healing skin ulcer (1) were seen in 2 patients (8.7%). There were no major procedure-related complications.Conclusion: Polidocanol sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications. [ABSTRACT FROM AUTHOR]

Purpose: To determine the incidence and risk factors of renal dysfunction after abdominal endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR).Materials and Methods: The study consisted of 227 patients treated with EVAR and 90 with TEVAR for aortic aneurysms. Parameters, including patients' background factors, preoperative renal function, contrast dose and aortic wall irregularity on CT images were assessed in relation to postoperative renal dysfunction.Results: Deterioration of renal function was observed in 33 of 218 patients (15.1%) after EVAR and in 7 of 79 (8.9%) patients after TEVAR. Hemodialysis was required in one patient after EVAR. In EVAR, renal dysfunction correlated with age (p = 0.034) and occlusion of accessory renal artery (p = 0.0001). In TEVAR, renal dysfunction correlated with age (p = 0.021), contrast dose (p = 0.042) and irregularity of the descending aortic wall (p = 0.023). In a multiple regression analysis, postoperative renal dysfunction was correlated with occlusion of accessory renal artery (p = 0.0003) after EVAR, and age (p = 0.02), contrast dose (p = 0.026) and irregularity of the descending aortic wall (p = 0.042) after TEVAR.Conclusion: Occlusion of accessory renal artery in EVAR, and age, contrast dose and irregularity of the descending aortic wall in TEVAR were considered to be predictors of postoperative renal dysfunction. [ABSTRACT FROM AUTHOR]

Purpose: This study was designed to assess the safety and effectiveness of ethanolamine oleate (EO) sclerotherapy combined with transarterial embolization using a liquid adhesive agent ( n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs). Methods: Twenty-four patients with symptomatic AVMs in the head and neck ( n = 15), extremity ( n = 5), and trunk ( n = 4) with a mean age of 44 years (range, 18-78) treated with EO sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 7 type II (arteriolovenous fistulae), 6 type IIIa (arteriolovenulous fistulae with nondilated fistula), and 11 type IIIb (arteriolovenulous fistulae with dilated fistula). Transarterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. EO mixed with contrast material was delivered by percutaneous direct puncture or by catheterization into the draining vein under balloon occlusion. Results: Three (13 %) of 24 patients were cured, 17 (71 %) had partial remission, and 4 (16 %) no remission. Treatment was considered effective (cure and partial remission) in 20 patients (83 %). Four patients (16 %) experienced transient minor complications, including self-healing skin ulcer ( n = 3) and localized deep venous thrombosis ( n = 1). There were no major complications. Conclusions: EO sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the feasibility and safety of CT-guided radiofrequency (RF) ablation by caudal-cranial oblique insertion using multiplanar reformation (MPR) images for hepatocellular carcinomas (HCCs). Materials and methods: Twenty-two HCCs in 19 patients that were difficult to demonstrate on ultrasound (mean tumor diameter was 17.5 mm) were treated with CT-guided RF ablation by caudal-cranial oblique insertion to avoid pneumothorax, using MPR images after transcatheter arterial chemoembolization. The insertion point and direction of insertion, avoiding aerated lung parenchyma, bones, large vessels, and intestine, were sought on the MPR images. Technical success was defined as complete eradication of tumor enhancement in the contrast-enhanced CT. Local tumor progression was defined by the appearance of enhanced tumor adjacent to the zone of ablation. The technical success rate, local tumor progression, and complications were investigated. Results: The coronal plane was used for insertion in 18 tumors, the sagittal plane in 3 tumors, and the oblique plane in 1 tumor. RF electrode placement was successful and complete necrosis was obtained in all cases. During the mean follow-up period of 38.0 months, local tumor progression was not detected in any of the patients. There were no major complications, including pneumothorax. Conclusion: CT-guided RF ablation by caudal-cranial oblique insertion using MPR images is a feasible and safe therapeutic option. [ABSTRACT FROM AUTHOR]

We report a case of ruptured renal artery aneurysm successfully treated by emergent transcatheter embolization with microcoils. A 66-year-old woman was referred for emergency treatment after presenting with sudden-onset left flank pain and vomiting. Blood examination showed anemia. Computed tomography demonstrated a partly calcified mass with massive retroperitoneal hematoma. With the diagnosis of a ruptured left renal artery aneurysm, emergency angiography was performed. Left renal arteriography demonstrated a saccular aneurysm at the lower aspect of the renal hilum. A total of five microcoils were placed at the arterial branch, including the orifice of the aneurysm. The first coil was partly lodged in a branch near the orifice of the aneurysm that was used as an "anchor" to prevent subsequent coils from migrating and effectively occluding the parent artery with a short segment. Two branches originating from the renal hilum were preserved. The postoperative course was favorable. Endovascular treatments, including coil embolization, appear to be effective, safe, and less invasive than surgery. This method should be considered as a treatment of choice for ruptured renal artery aneurysm. [ABSTRACT FROM AUTHOR]

Kovac et al (1) have shown that bikaverin uncouples oxidative phosphorylation of mitochondria at 20µg/ml (52 nmol/ml) in the reaction system without magnesium (Mg2+). In the present study, the effects of bikaverin on mitochondrial reactions were reexamined in detail at various concentrations both in the reaction systems with and without magnesium, using isolated rat liver mitochondria and submitochondrial particles (SMP) to characterize its mode of actions to mitochondrial respiration at low concentrations (<30nmol/mg mitochondrial protein). It was concluded that bikaverin showed no uncoupling effect (no decrease in P/O ratio) at low concentrations and did it at high concentrations in consequence of disturbing the ion permeability in the mitochondrial inner membranes. At low concentrations, bikaverin repressed both NAD- and succinate-linked respirations, but did not interfere with electron transport and energy transfer systems of mitochondria. [ABSTRACT FROM AUTHOR]

The toxic effect of rubroskyrin, a modified bis-anthraquinone pigment from Penicillium islandicum Sopp, on mitochondrial respiration has been studied by using isolated rat liver mitochondria, comparing with those of luteoskyrin and rugulosin which are well known islandicum toxins. It was found that rubroskyrin exerted an uncoupling effect on mitochondrial respiration, abating the respiratory control ratio (RCR) by a dose dependent manner (UD: 10 μM) and markedly depressed state 3 respiration at high concentrations, whereas such respiration-impairing effects of luteoskyrin and rugulosin were not detected at the concentrations tested (max. 35 μM). The involvement of redox-reaction was not detected in the uncoupling effect of the quinone pigment, rubroskyrin. Spectroscopic study at various pHs revealed that rubroskyrin possessed a pK value within the range of physiological pH, suggesting that rubroskyrin is a weak acid-type uncoupler capable of conducting protons across mitochondrial inner membrane. [ABSTRACT FROM AUTHOR]