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Background: Endovascular treatment of visceral and renal artery aneurysms and pseudoaneurysms is an effective, minimally invasive treatment that has been successfully used since the early 1990s, with refined and expanded techniques and tools currently offering excellent outcomes. Due to increased detection of such lesions in recent years, many of which are asymptomatic, revision of the indications for intervention and the correct endovascular treatment approaches has become essential. Purpose: This document will presume that the indication for treatment is clear and approved by the multidisciplinary team and will define the standards required for the performance of each intervention, as well as their relative advantages and limitations. CIRSE Standards of Practice documents are not intended to impose a standard of clinical patient care, but recommend a reasonable approach to, and best practices for, the performance of the endovascular treatment of visceral and renal artery aneurysms and pseudoaneurysms. Methods: The writing group was established by the CIRSE Standards of Practice Committee and consisted of five clinicians with internationally recognised expertise in endovascular treatments. The writing group reviewed the existing literature on visceral and renal artery aneurysms and pseudoaneurysms, performing an evidence search using PubMed to identify publications in English and relating to human subjects from 1990 to 2022. The final recommendations were formulated through consensus. Results: Endovascular treatment has an established role in the successful management of visceral and renal artery aneurysms and pseudoaneurysms, and this Standards of Practice document provides up-to-date recommendations for its safe performance. [ABSTRACT FROM AUTHOR]

Modeling blood flow in aneurysms treated with coils could be used to understand the complete embolization of the aneurysm, through thrombus formation that fills the entire sac. Modeling of the endovascular coil mass as a porous medium is a technique that allows for study of aneurysm hemodynamics, efficiently for patient-specific treatment outcome predictions. Models in the literature use mean porosity of coils in the aneurysmal volume, proving inadequate for outcome prediction. However, models that consider heterogeneous porosity distribution have shown more accurate hemodynamics. We recently published the porous crown model, considering the heterogeneous coil mass distribution, validated on two patients. This study aims (i) to validate the porous crown model for a larger cohort (eight patients), and (ii) to propose a porous medium model translatable to clinical practice in treatment planning. We analyzed the porosity distribution of the endovascular coils deployed inside the cerebral aneurysm phantoms of eight patients using 3D x-ray synchrotron images. The permeability and inertial factor of the porous crown model are calculated using previously published methodology. We propose a new "bilinear" porous model, that uses the same hypothesis, but the permeability and inertial factor can be defined from just basic information available in the neuro-suite, i.e., the aneurysmal sac volume and the coil volume fraction targeted by the neurosurgeon. These two models are compared to the coil-resolved simulations, considered as the gold standard. The results show that both the porous crown model and the bilinear model produce similarly accurate hemodynamics in the aneurysm. The error in the standard (mean porosity) porous model is 66%, whereas the error of the bilinear model is 26%, compared to the coil-resolved. The bilinear model is promising as a means of treatment outcome prediction at time of intervention. [ABSTRACT FROM AUTHOR]

Endovascular embolization techniques are showing an extraordinary potential to treat patients suffering from complex neurovascular malformations. The embolization with liquid embolic agents via Onyx is a prominent approach to treat arteriovenous malformation (AVM). However, intraoperative reflux of the liquid agents can be very challenging and, thus, is impairing full success of endovascular treatment. A possible technique to prevent intraoperative endovascular reflux is the pressure-cooker technique (PCT) utilizing coils to build a wedge proximal to the AVM. Few modifications of the PCT have been developed in the recent years to improve effectiveness of embolization procedure. Hereby, we present a novel PCT modification utilizing extra-soft Kaneka coils and glue to build well-fitting wedges. After the application of extremely soft bare coils with high trackability, flexibility and crossability, liquid agents can be injected with reduced reflux. We think the pressure-cooker technique with extra-soft Kaneka coils enables more efficient embolization in even farther, tinier and more tortuous target vessels. This technical note presents two illustrative patient cases with treatment-refractory, high-grade cerebral arteriovenous malformations which were successfully treated via embolization with PCT in which the plug was formed with Kaneka coils. [ABSTRACT FROM AUTHOR]

Objectives: Photon-counting detector computed tomography (PCD-CT) is a promising new technique for CT imaging. The aim of the present study was the in vitro comparison of coil-related artifacts in PCD-CT and conventional energy-integrating detector CT (EID-CT) using a comparable standard brain imaging protocol before and after metal artifact reduction (MAR). Methods: A nidus-shaped rubber latex, resembling an aneurysm of the cerebral arteries, was filled with neurovascular platinum coils and inserted into a brain imaging phantom. Image acquisition and reconstruction were repeatedly performed for PCD-CT and EID-CT (n = 10, respectively) using a standard brain imaging protocol. Moreover, linear interpolation MAR was performed for PCD-CT and EID-CT images. The degree of artifacts was analyzed quantitatively (standard deviation in a donut-shaped region of interest) and qualitatively (5-point scale analysis). Results: Quantitative and qualitative analysis demonstrated a lower degree of metal artifacts in the EID-CT images compared to the total-energy PCD-CT images (e.g., 82.99 ± 7.89 Hounsfield units (HU) versus 90.35 ± 6.28 HU; p < 0.001) with no qualitative difference between the high-energy bin PCD-CT images and the EID-CT images (4.18 ± 0.37 and 3.70 ± 0.64; p = 0.575). After MAR, artifacts were more profoundly reduced in the PCD-CT images compared to the EID-CT images in both analyses (e.g., 2.35 ± 0.43 and 3.18 ± 0.34; p < 0.001). Conclusion: PCD-CT in combination with MAR have the potential to provide an improved option for reduction of coil-related artifacts in cerebral imaging in this in vitro study. Key Points: • Photon-counting detector CT produces more artifacts compared to energy-integrating detector CT without metal artifact reduction in cerebral in vitro imaging after neurovascular coil-embolization. • Spectral information of PCD-CT provides the potential for new post-processing techniques, since the coil-related artifacts were lower in PCD-CT images compared to EID-CT images after linear interpolation metal artifact reduction in this in vitro study. [ABSTRACT FROM AUTHOR]

Purpose: Computational fluid dynamics (CFD) has been used to evaluate the efficiency of endovascular treatment in coiled cerebral aneurysms. The explicit geometry of the coil mass cannot typically be incorporated into CFD simulations since the coil mass cannot be reconstructed from clinical images due to its small size and beam hardening artifacts. The existing methods use imprecise porous medium representations. We propose a new porous model taking into account the porosity heterogeneity of the coils deployed in the aneurysm. Methods: The porosity heterogeneity of the coil mass deployed inside two patients' cerebral aneurysm phantoms is first quantified based on 3D X-ray synchrotron images. These images are also used to compute the permeability and the inertial factor arising in porous models. A new homogeneous porous model (porous crowns model), considering the coil's heterogeneity, is proposed to recreate the flow within the coiled aneurysm. Finally, the validity of the model is assessed through comparisons with coil-resolved simulations. Results: The strong porosity gradient of the coil measured close to the aneurysmal wall is well captured by the porous crowns model. The permeability and the inertial factor values involved in this model are closed to the ideal homogeneous porous model leading to a mean velocity in the aneurysmal sac similar as in the coil-resolved model. Conclusion: The porous crowns model allows for an accurate description of the mean flow within the coiled cerebral aneurysm. [ABSTRACT FROM AUTHOR]

Background: Embolisation of the parenchymal tract is a key step after any other transhepatic or transplenic percutaneous portal vein catheterization since eventual venous bleeding is difficult to control and may require surgical management. Different techniques have been proposed to perform tract embolisation. The aim of this study is to compare the safety and efficacy of different techniques of haemostasis of the parenchymal tract. Materials and methods: All the interventional procedures with percutaneous transhepatic or transplenic access to the portal vein (excluding ipsilateral portal vein embolisation) from January 2010 to July 2020, in two tertiary hospitals, were retrospectively analyzed. The following data were evaluated: access site, the technique of embolisation, technical success in terms of immediate thrombosis of the tract, safety and clinical efficacy in terms of the absence of hemorrhagic and thrombotic complications. Results: One-hundred-sixty-one patients underwent 220 percutaneous transhepatic or transplenic portal vein catheterization procedures. The main indications were pancreatic islet transplantation, portal anastomotic stenosis after liver transplantation, and portal vein thrombosis recanalization. As embolic materials gelfoam was used in 105 cases, metallic micro-coils in 54 cases, and cyanoacrylic glue in 44 cases; in 17 cases the parenchymal tract was not embolized. Technical success was 98% without significant difference among groups (p-value = 0.22). Eighteen post-procedural abdominal bleedings occurred, all grade 3 and were managed conservatively; difference among groups was not significant (p-value = 0.25). We detected 12 intrahepatic portal branch thromboses not related to the embolisation technique; only one case of non-target embolisation was documented after liver tract embolisation with glue, without clinical consequences. Conclusion: Embolisation of the parenchymal tract after percutaneous portal vein catheterization is technically safe and effective. No significant differences were found between coils, glue, and gelfoam in effectiveness and complications rate. Level of evidence: Level 3, Cohort study. [ABSTRACT FROM AUTHOR]

Background: Superior rectal artery (SRA) aneurysms are rare. Although melena is the most common symptom, it has not been observed in cases of aneurysms located in the SRA trunk. Here, we report a case of a ruptured SRA trunk aneurysm successfully treated with coil embolization. Including our case, three of the four reported cases of SRA trunk aneurysms were related to neurofibromatosis type 1 (NF1). Case presentation: A 52-year-old woman with NF1 was referred to our hospital for the investigation of an abdominal mass with back pain. She had previously undergone a blood transfusion at another hospital for anemia without melena. Computed tomography angiography revealed a ruptured SRA trunk aneurysm measuring 3 cm in diameter and surrounded by a retroperitoneal hematoma. The aneurysm was isolated by embolizing the SRA trunk distally and proximally. Distal embolization was performed retrogradely from the internal iliac artery (IIA) via the middle rectal artery (MRA)-SRA anastomosis because the antegrade approach from the inferior mesenteric artery (IMA) failed. To our knowledge, this is the first case of successful coil embolization of an IMA branch through the IIA. Conclusion: SRA trunk aneurysms are rare; however, they are frequently associated with NF1. Antegrade distal embolization beyond the aneurysm is sometimes difficult to achieve. In such cases, a retrograde approach via MRA-SRA anastomosis can be the choice for isolating SRA trunk aneurysms. [ABSTRACT FROM AUTHOR]

In this paper, the authors propose a flexible automatic procedure for optimizing multiphase single-layer winding end-connections by the differential evolution algorithm. By using the winding distribution in slots as a predefined input, connections between phase conductors located in different slots are determined to minimize the winding average coil pitch and to simultaneously maximize the number of coils with identical coil pitch. For an adopted geometrical shape and number of turns of individual coils, minimization of winding average coil pitch results in minimized end-connection length, winding resistances, end-leakage inductances, winding mass and copper losses, while machine efficiency and power factor are maximized. However, maximizing the number of identical coils simplifies and speeds up the process of coil fabrication during machine assembly, but potentially leads to higher average coil pitch. The proposed method is applied to single-layer windings with different slot, pole and phase combinations, where it is proven that the method automatically provides end-connection arrangements which are better or equal in terms of copper usage and simplicity of fabrication than the ones found in the literature. Verification is conducted by comparing overall performance of several Rotor Permanent Magnet Flux Switching motors with different stack lengths, outer diameters and optimized end-windings by means of 2D finite element analysis and 3D analytical approach. The proposed method is conceived as an automatic tool for optimization of single-layer winding end-connections during comprehensive electrical machine design optimization. [ABSTRACT FROM AUTHOR]

Open surgery remains the mainstay of treatment for acute type A aortic dissection and should be offered to most patients. However, there are elderly patients in which surgical treatment may be deemed extremely high risk or futile. Endovascular treatment approaches have been applied to a small number of these patients and data are limited to case reports and small series. The application of endovascular therapies to ascending aorta is currently limited by anatomical and technical challenges posed by the dynamic motion of the ascending aorta and the proximity of vital structures to intended landing zones (aortic valve, coronary arteries, and supra-aortic branches) and lack of specially designed endografts to address these issues. While thoracic endovascular aortic repair (TEVAR) has replaced open aortic repair for a suitable lesion in distal aortic dissection, some selected patients with type A aortic dissection at high surgical may be candidates. Hence, there is potential because, in proximal (Stanford type A) dissections, 10–30% of patients are not accepted for surgery, and 30–50% are technically amenable for TEVAR. Recent experience has shown that carefully selected patients with favorable anatomical characteristics may be subject to endovascular stent-graft treatment as a last resort with mixed results. Technical improvement is necessary to offer. satisfactory endovascular options in non-surgical candidates. [ABSTRACT FROM AUTHOR]

Background: The safety controls in Resonance Magnetic Imaging (MRI) diagnostic site are numerous and complex. Some of these are contained in international directives and regularly conducted by medical physics expert after acceptance tests, consisting of a series of checks, measurements, evaluations called quality controls (QCs) and made to guarantee the image quality of the equipment. In this context, ensuring that the coils are in proper operating conditions is important to prevent and reduce errors in use and to preserve patient safety. Results: A study by thermography was conducted to evaluate temperature changes of MRI coils during Quality Control (QC), in order to prevent any problems for the patient due to Radio Frequency waves. This experiment involves use of a thermal camera to detect temperature variations during MRI scans using head and body coils of two different tomography 1.5 T and 3.0 T static magnetic field. Thermal camera was positioned inside the MRI room to acquire images every 15 s for all the scansions duration. The observations have shown a temperature increase only for body coil of 1.5 MRI tomography, whereas no significative temperature variation has occurred for the other coils under observation. This temperature increase was later related to a fault of such coil. Conclusions: The authors believe this simple method useful as first approach, during routinely QCs, to verify coils functioning and so to avoid patient hazards and are preparing a methodological study about functioning of the coils with respect to their temperature variation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the safety and efficacy of transhepatic puncture tract embolization with n-butyl cyanoacrylate (n-BCA) versus coils after percutaneous transhepatic portal vein interventions in patients with hepatocellular carcinoma (HCC). It was also the aim of the study to evaluate the extent of artifacts in CT exams during FU. Methods: Single-center retrospective study from 2017–2019 in 190 patients who underwent percutaneous transhepatic portal vein interventions. The transhepatic puncture tracts were embolized with n-BCA in 88 patients (Group A) and with coils in 102 patients (Group B). Procedure-related complications and image noise around coils and n-BCA were compared between the groups. No significant differences were noted at baseline between both groups (platelets, coagulation, liver disease, types of procedures, liver function, liver tumors). Results: All patients underwent transhepatic puncture tract embolization. Procedure-related complications were only observed in patients from Group B: subcapsular hemorrhage (n = 2; 1.96%), hepatic artery hemorrhage (n = 1; 0.98%), and pseudoaneurysms combined with hemobilia occurred (n = 1; 0.98%). In Group A, the distal part of the punctured portal vein branch was embolized with n-BCA in 1 patient (1.14%). Four major complications in Group B Vs 0 in Group A were observed, respectively (p < 0.0001). The image noise around n-BCA was significantly lower than that around coils (10.7 ± 1.7 HU vs. 54.3 ± 15.0 HU, p <.001). Conclusions: n-BCA tract embolization is more effective than using coils, with fewer bleeding events, at the cost of a higher potential for unintended embolization of portal vein branches. [ABSTRACT FROM AUTHOR]

Purpose: Visceral artery pseudoaneurysms (VAPAs) are uncommon in clinical practice but may have serious clinical outcomes up to death. Endovascular management is a safe effective alternative option to traditional surgical procedures. This study assesses the outcome of different embolic materials and techniques used in the endovascular management of VAPAs. Materials and methods: This is a two-center retrospective analysis of endovascular embolisation of 46 VAPAs, with a mean pseudoaneurysm size of 13 ± 11.35 mm, that were urgently managed between July 2018 and March 2020. Patients' presentations were GIT hemorrhage, intrabdominal hemorrhage, hematuria, and abdominal pain in 34.78%, 30.43%, 23.91%, and 10.87% respectively. Management using coils only was done in 28/46 patients (60.87%), NBCA glue only in 16/46 patients (34.78%), combined coils and NBCA glue in 1/46 patient (2.17%), and Amplatzer plugs only in 1 patient (2.17%). The management techniques were sac packing in 9/46 patients (19.57%), inflow occlusion in 28/46 patients (60.87%) and trapping in 9/46 patients (19.57%). All patients were followed-up for 1 year after the procedure. Results: The overall clinical success and periprocedural complication rates were 93.48%, and 15.22% respectively, and 30-day mortality was zero. Clinical success was 92.86% in the coil subgroup (n = 28), and 93.75% in the NBCA glue subgroup (n = 16). The technical success rate was 100%. Effectiveness of the procedures during the follow-up was 97.83%. Target lesion re-intervention rate was 2.17%. Conclusion: Transarterial embolisation can provide high technical and clinical success rates with low periprocedural complication and re-intervention rates, as well as satisfactory procedure effectiveness in the management of VAPAs. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to compare endosaccular flow disruptor (EFD) for treatment of basilar tip aneurysm (BTA) with coiling in terms of safety and efficacy. Methods: We retrospectively reviewed patients treated with an EFD for BTAs at our institution between 2013 and 2019 to standard coiling from the same period (control group). Patient demographics, aneurysm characteristics, procedural data, complications and clinical and angiographic outcome were compared between groups. Results: Twenty-three (56%) patients were treated with an EFD and eighteen (44%) patients were treated with coiling. Average aneurysm size was 8 mm in the EFD group and 6.9 mm in the coiling group, respectively (P = 0.2). Average fluoroscopy time, treatment DAP and air kerma were 33 min, 76 Gycm2 and 1.7 Gy in the EFD group and 81 min, 152 Gycm2 and 3.8 Gy in the coiling group, respectively (P < 0.001). In the EFD group, clinically relevant thromboembolic complications occurred in one patient (4%) vs. in 5 patients (28%) in the coiling group (P = 0.07). In each group, 4 patients had an unfavourable outcome at discharge (P = 0.7). Adequate occlusion rates were 96% in the EFD group and 100% and coiling group. Six (26%) patients were prescribed long-term antiplatelet therapy in the EFD group vs. eleven (61%) patients in the coiling group (P = 0.02). Conclusion: Both treatment concepts provided similar technical success and safety. However, procedure time, radiation exposure and a need for long-term antiaggregation were lower with EFD. [ABSTRACT FROM AUTHOR]

A molding coil is prepared by filling and dry pressing granulated alloy magnetic powders directly onto enameled wire. As the molding coil is developed toward miniaturization, the granules consisting of magnetic powder and organic binder cannot uniformly fill the small space in the coil center column during molding. This leads to a porous microstructure or cracks. The uneven packing problem in the coil center column was effectively solved in this study by applying a screen printing process using high-solid-content magnetic pastes. Bisphenol A epoxy resin has the benefits of excellent mechanical, bonding, electrical, corrosion resistance, low shrinkage and low cost properties. However, the viscosity is too high for use as a binder for high-solid-content magnetic paste. The magnetic paste viscosity can be reduced by substituting some low viscosity reactive diluent (butyl glycidyl ether) for Bisphenol A epoxy resin. It was observed that the relative density and magnetic properties (such as initial permeability, saturation magnetization, and core loss) can be effectively improved by increasing the monomer addition because the monomer acts as a lubricant that helps the magnetic particles rearrange during compaction. However, as monomer addition becomes greater than half the epoxy resin weight percent, the sample bending strength decreases. [ABSTRACT FROM AUTHOR]

This article presents the impact of MgB2 wire bending and diameter on transport critical current density and irreversible magnetic field of a resultant coil. Unreacted MgB2 wires 500 mm in length and 0.63 or 0.83 mm in diameter have been used in the fabrication of small diameter (14 mm) superconducting coils. The coils were subsequently annealed under isostatic pressure of 1 GPa for 15 min at 700 °C and 725 °C. Our results indicate that larger wire diameter, higher annealing temperature, and bending lead to slight reduction of critical current density and irreversible magnetic field in the coil. [ABSTRACT FROM AUTHOR]

Purpose: Postpancreatectomy hemorrhage (PPH) is one of the leading causes of mortality after pancreatic resection. Late onset PPH is most often treated using a transarterial approach. The aim of this study was to analyze risk factors for in-hospital mortality after endovascular treatment. Methods: Between 2012 and 2017, patients who were treated endovascular due to PPH were identified from a retrospective analysis of a database. Risk factors for mortality were identified by univariate analysis. Results: In total, 52 of the 622 patients (8.4%) underwent endovascular treatment due to PPH. The primary technical success achieved was 90.4%. In 59.6% of patients, bleeding control was achieved by placing a stent graft and in 40.4% by coil embolization. The primary 30-day and 1-year patency of the placed covered stents was 89.3% and 71.4%, respectively. The 60-day mortality was 34.6%. The reintervention rate was higher after stent graft placement compared to coiling (39.3% vs. 21.1%, P = 0.012). In the univariate analysis the need for reintervention was associated with a higher in-hospital mortality (21.2% vs. 7.7%, P = 0.049). The use of an antiplatelet agent was associated with a decreased in-hospital mortality in the univariate (11.5% vs. 25%, P = 0.024) and multivariate analysis (HR 3.1, 95% CI 1.1-9, P = 0.034), but did not increase the risk of rebleeding. Conclusion: Endovascular management of delayed PPH has a high technical success rate. Stent graft placement showed a higher reintervention rate. The need for reintervention was associated with a higher in-hospital mortality but did not differ between coiling and stent graft placement. [ABSTRACT FROM AUTHOR]

An important challenge in the wireless power transfer is the sizing of the coils for transmission and energy reception. The output power in a wireless power transfer system can be determined by analytical formulation; however, the effects of using some geometry or material for the transmitter and receiver coil assembly are not easily quantifiable by the analytical method. This work quantifies by numerical simulation the impact on output power changing the separation between the transmitter coil and receiver, materials, geometries and number of turns. The quantities obtained allowed to determine a model for coupling coefficient to compute optimal frequency for the power transfer. The analysis and evaluation of these parameters were developed through an electromagnetic simulator with finite element; the work considers planar circular and square coils. Experimental results were obtained in order to validate the proposed model to compute the wireless power transferred. The document contributes to identify the important parameters to be controlled or modified in the coils with the purpose to optimize the power transmission for a wireless system. [ABSTRACT FROM AUTHOR]

Copyright of Der Radiologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The tension modes of cold-rolled strip coiling are analyzed. The dependences of the stress-strain state of the coils on the strain degree, temperature, velocity, strip rolls surface roughness during cold strip rolling are considered. Coiling methods provide improvement of production efficiency and the quality of cold-rolled sheet steel by preventing the appearance of such rolling defects as bent fractures and coil shape defects. [ABSTRACT FROM AUTHOR]

Dural arteriovenous fistulas (DAVF) involving the anterior and posterior condylar vein at the skull base are rare but important to recognize. Due to the highly variable anatomy of the venous system of the skull base, detailed anatomical knowledge is essential for correct diagnosis and appropriate treatment of these lesions. In this report we review the normal anatomy of the condylar veins and describe rare and, to our knowledge, not previously reported anatomical variants. We also highlight the treatment modalities for these lesions with focus on the endovascular transvenous occlusion based on four consecutive cases from our center. [ABSTRACT FROM AUTHOR]

Abstract—Shape defects in coils of cold-rolled strip are analyzed. An algorithm for assessing the stability loss of coils is proposed, on the basis of a fundamentally new approach to calculating the stress–strain state in strip winding on the drum of the cold-rolling mill. Methods are recommended for preventing the following defects of coils of cold-rolled thin steel sheet: sagging, folded structure, mutual slip of the layers, and telescopic distortion. [ABSTRACT FROM AUTHOR]

The isolation and characterization of 42 unique nonfunctional missense mutants in the bacterial cytosolic β-galactosidase and catechol 2,3-dioxygenase enzymes allowed us to examine some of the basic general trends regarding protein structure and function. A total of 6 out of the 42, or 14.29% of the missense mutants were in α-helices, 17 out of the 42, or 40.48%, of the missense mutants were in β-sheets and 19 out of the 42, or 45.24% of the missense mutants were in unstructured coil, turn or loop regions. While α-helices and β-sheets are undeniably important in protein structure, our results clearly indicate that the unstructured regions are just as important. A total of 21 out of the 42, or 50.00% of the missense mutants caused either amino acids located on the surface of the protein to shift from hydrophilic to hydrophobic or buried amino acids to shift from hydrophobic to hydrophilic and resulted in drastic changes in hydropathy that would not be preferable. There was generally good consensus amongst the widely used algorithms, Chou-Fasman, GOR, Qian-Sejnowski, JPred, PSIPRED, Porter and SPIDER, in their ability to predict the presence of the secondary structures that were affected by the missense mutants and most of the algorithms predicted that the majority of the 42 inactive missense mutants would impact the α-helical and β-sheet secondary structures or the unstructured coil, turn or loop regions that they altered. [ABSTRACT FROM AUTHOR]

The aim of this paper was to construct a mathematical model of a drive system with ironless permanent magnet synchronous linear motor and to animalize the influence of the magnetic field distribution function on the model’s accuracy and ease of simulation computation. The studied motor employs an U-shaped stationary guideway with permanent magnets placed perpendicularly to the motor’s direction of motion and a forcer with three sets of rectangular coils subjected to alternating external electrical voltage. The system’s parameters are both mechanical (number of magnets and coils, size of magnets, distances between magnets, size of coils) and electromagnetic (auxiliary magnetic field, permeability, coil’s resistance). Lorentz force allows for the transition from electromagnetic parameters to mechanical force, and Faraday’s law of induction creates a feedback between the forcer’s speed and coils voltage. An Ampere’s model of permanent magnet is used to determine the function of auxiliary magnetic field distribution throughout the stator. Two simplified distribution functions are introduced and studied. During validation, external current function is applied to each coil (serving as excitation), while the displacement of forcer in time is the output function. Model parameters are found via genetic algorithms such that the numerical solution of the model best fits experimental data. Several cases of motor operation are compared against simulation results showing good coincidence between computation and experiment. [ABSTRACT FROM AUTHOR]

Purpose: The safety of liquid embolics over the conventional coils for the treatment of non-variceal upper gastrointestinal bleeding (UGIB) approach is still unclear. Purpose of this study is to assess the safety of ethylene-vinyl alcohol copolymer (EVOH 6%) over coils in the treatment of UGIB.Materials and Methods: All the upper gastrointestinal tract embolization procedures performed in a single center in a 6-year period were reviewed. Patients embolised with coils (Group A) versus those embolised with EVOH 6% (Group B) were compared. Technical/clinical success, bleeding recurrence, complication and mortality rates were analyzed.Results: A total 71 patients were included in the study (41 Group A and 30 Group B). Coagulopathy was present in 21% of Group A and 46% of Group B patients (p < 0.05). Technical and clinical success was 97.6 and 92.7% for Group A, and 100 and 93.3% for Group B respectively, (p > 0.05). Ten patients (17% Group A; 10% Group B) re-bled within the first 36 h and all of them were re-treated successfully with a second embolization. In Group A one major complication (bowel ischemia) occurred. No complication occurred in Group B. The survival rate in the first 30 days was 90.3% for group A and 90% for group B (p > 0.05).Conclusion: This study demonstrated EVOH 6% appears to be as safe and effective as coils in the treatment of non-variceal UGIB. [ABSTRACT FROM AUTHOR]

The sources of defects associated with stability loss of cold-rolled strip coils are established. The influence of the winding-drum structure in cold-rolling mills on the stress-strain state of the coils, both before and after removal from the winding system, is analyzed in detail. The possibility of modifying the stress-strain state of the coils by regulating the rigidity of the winding drum is considered. Recommendations are made regarding the selection of the winding technology for rolled strip. [ABSTRACT FROM AUTHOR]

Although evidence of mosquito coils' impact on disease epidemiology is limited, they are popularized as mosquito-borne disease prevention devices. Their usage affects the environment, human and mosquito health. This study investigated the perception, usage pattern and efficacy of coils in a predominantly poor malaria-endemic Ghanaian peri-urban area. Information on protection methods, perception and usage pattern was garnered using questionnaires. The efficacy of commonly used coils in the area was then assessed on the malaria vector, Anopheles gambiae, in a glass chamber. Sole or co-application of mosquito control methods and risky usage practices were reported. Coils were deemed harmful to humans and mosquitoes, and their perceived effectiveness varied, with several factors influencing their purchase. High d-allethrin concentration coils induced quicker mosquito knockdown; however, mortality was less than 85%. The coil usage pattern compromises users' health and can enhance mosquito tolerance to d-allethrin. The coils were ineffective against the vector, outlining a dichotomy between the users' perception of efficacy and the observed efficacy. Hence, the usage of other safer and more effective vector control methods should be encouraged to protect households. [ABSTRACT FROM AUTHOR]

The formation of flexure defects when coils of thin cold-rolled steel strip are unwound is considered. The influence of the strip thickness, surface roughness, temperature, properties of the steel, and other factors on the formation of such defects is analyzed. Measures are proposed for the prevention of the defects. [ABSTRACT FROM AUTHOR]

Purpose: Coil embolization of pulmonary arteriovenous malformations (PAVMs) has a high re-canalization/re-perfusion rate. Embolization with Amplatzer plugs has been previously described, but the long-term efficacy is not established. This study reports the experience of a referral medical center with the use of coils and Amplatzer plugs for treating PAVMs in patients with hereditary hemorrhagic telangiectasia.Methods: The study was approved by the Institutional Review Board with waiver of informed consent. The cohort included all patients who underwent PAVM embolization in 2004-2014 for whom follow-up imaging scans were available. The medical files were retrospectively reviewed for background data, embolization method (coils, Amplatzer plugs, both), and complications. Re-canalization of treated PAVMs was assessed from intrapulmonary angiograms (following percutaneous procedures) or computed tomography angiograms. Fisher's exact test and Pearson Chi-squared test or t test were used for statistical analysis, with significance at p < 0.05.Results: 16 patients met the study criteria. Imaging scans were available for 63 of the total 110 PAVMs treated in 41 procedures. Coils were used for embolization in 37 PAVMs, Amplatzer plugs in 21, and both in five. Median follow-up time was 7.7 years (range 1.4-18.9). Re-canalization was detected in seven vessels, all treated with coils; there were no cases of re-canalization in plug-occluded vessels (p = 0.0413).Conclusion: The use of Amplatzer plugs for the embolization of PAVMs in patients with hemorrhagic telangiectasia is associated with a significantly lower rate of re-canalization of feeding vessels than coils. Long-term prospective studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]

The formation of surface defects when annealed thin cold-rolled steel sheet is uncoiled for temper rolling is analyzed. The appearance of such defects is mainly due to adhesion and welding of the contacting surfaces of the turns in the coil. The influence of the strip thickness, surface roughness, temperature, properties of the metal, and other factors on the stress-state of the coil and the likelihood of surface defects is analyzed. Preventive measures are recommended. [ABSTRACT FROM AUTHOR]

The growth in understanding of the pathophysiological relationships between various neurovascular diseases in the past decades has increased the significance and need for endovascular treatment. Consequently, an extraordinary development of different embolic agents was indispensable. The present work first presents the historical milestones in the discovery of various embolic materials used for neurovascular interventions. In the second part, the current endovascular embolization procedures, requiring both liquid and solid embolic agents, are discussed. In some cases and diseases the combination of both may be mandatory. Special emphasis is placed on the consideration needed when choosing appropriate embolic materials, chiefly depending on the goal of the endovascular procedure. Furthermore, the present understanding of the specifics in angioarchitecture and hemodynamics, leading to the most suitable form of access to the vascular lesion, will be covered. Regarding the latter, it is important to note that the aim should always be to achieve optimal superselectivity while being aware of all approaches, ranging from transarterial and transvenous to direct puncture. Finally, based on the limitations of the currently available embolic materials, we present a brief outlook on the future of new liquid and solid embolic agents. [ABSTRACT FROM AUTHOR]

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Purpose: Endovascular management with good preservation of the internal carotid artery (ICA) has become the first-line choice for the treatment of direct carotid cavernous fistulas (CCFs). Multiple treatments have been tried with variable success. This article elucidates the effectiveness and safety of embolization with Onyx and coils under transarterial balloon protection. Materials and Methods: We reviewed 18 cases with direct CCFs in our case library. All cases were treated with transarterial or transvenous embolization with Onyx and coils under intra-arterial balloon protection. Results: Immediate angiography after embolization showed total occlusions in 16 patients and small residual fistulas in 2 patients. Good preservation of the ICA was observed in all cases. The average volume of Onyx was 2.6 ml, and the average length of bare coils was 102.0 cm. Hydrogel-coated coils with an average length of 75.2 were used in five cases. Angiographic follow-ups of 16 patients showed no residual or recurrent fistula within 8 months (average 3.4). For the 2 patients with small residual fistulas, both received short-time angiographic follow-up within 3 month after the procedure. All follow-up angiograms showed no residual or recurrent fistula. Clinical follow-up of the other two recent patients showed no relapsing symptoms. There were no procedure-related complications, and no new symptoms occured in any patient. Conclusion: The technique of embolization using Onyx and coils under intra-arterial balloon protection is feasible for the treatment of direct CCFs, especially for patients with large fistula ostium and large cavernous sinus. This technique is an effective and safe option with rare complications. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to determine the effectiveness of a percutaneously inserted coil as a landmark before radiofrequency ablation (RFA) of poorly visible liver tumors on unenhanced computed tomography and ultrasound. Methods: This was a single-center, retrospective study of 46 consecutive patients treated from January 2008 to June 2012 with RFA under CT guidance for 57 poorly visible liver tumors after percutaneous coil insertion. Effectiveness was evaluated by the rate of local tumor progression (LTP), and the risk factors of LTP were evaluated by multiple univariate analysis. Results: After a mean follow-up of 15.9 months, the overall rate of LTP was 22.8 % (13/57). An increase in the distance between the coil and the center of the tumor was a predictive factor of LTP ( p = 0.005) and resulted in an increase in time to place the RFA probe. LTP was significantly reduced in case of coil placed within the tumor (10 vs. 43.5 %, p = 0.009). Conclusions: The effectiveness of the 'coil-assisted' RFA for poorly visible liver tumors is improved by centering the coil in the tumor in order to facilitate the placement of the RFA probe and equal to the results of RFA under direct image guidance. [ABSTRACT FROM AUTHOR]

In the last 10 years interventional neuroradiology has become established especially in the endovascular treatment of aneurysms as the preferred treatment according to level 1 evidence and more recently in the treatment of acute ischemic stroke. These interventions are performed as routine procedures in an increasing number of centers. This, however, necessitates that anesthesiologists and neuroradiologists become increasingly more familiar with the complementary expectations and potential pitfalls in working together to maximise efficiency and patient safety. As a further challenge there are different aspects to be considered in elective procedures and emergency procedures where time is brain. This article highlights these aspects for the two most common procedures: aneurysm treatment and multimodal recanalization treatment for acute ischemic stroke. [ABSTRACT FROM AUTHOR]

We report a novel strategy to study the chain dynamics of poly(acrylic acid) (PAA) in a relative concentrated solution (1.0 g/L). The strategy is based on the fluorescent probe (DCTPE) with unique aggregation-induced emission (AIE) characteristics. Free DCTPE molecules are non-emissive in aqueous solution, but they become highly emissive when trapped in polymer coils. The fluorescence intensity is proportional to the efficiency of trapping DCTPE molecules in polymer coils. By correlation the change of fluorescence intensity with the variation of pH value (from 1.78 to 12.06), the PAA chain's dynamics in the relatively concentrated solution have been elucidated into three processes. In the pH range from 12.06 to 6.0, PAA chains take an extended and non-folding conformation. Changing pH from 6.0 to 3.86, PAA chains are partially protonated and loosely packed polymer coils are formed. Further lowering the pH value of the solution (from 3.86 to 1.78), protonated segments dominate the PAA chains, and at the same time, the intermolecular hydrogen bonding takes effect, thus the polymer chains posses in the conformation of more compact coils. [ABSTRACT FROM AUTHOR]

Introduction: Permanent vessel sacrifice has become a routine for the management of aneurysms, pseudoaneurysms, tumors, and carotid blowouts. The purpose of this study is to describe a new technique for carotid and vertebral artery sacrifice using a combination of Onyx and coils and to assess its feasibility, safety, and efficacy. Methods: The technique consists of deploying a few coils in the parent vessel under proximal flow arrest followed by Onyx embolization directly into the coil mass. A total of 41 patients underwent carotid/vertebral artery sacrifice using this technique in our institution. Results: A total of 26 internal carotid arteries and 15 vertebral arteries were treated. In all but one patient, a balloon test occlusion was performed prior to permanent arterial sacrifice. The mean number of coils used was 6.8 (range, 2-19). The total volume of Onyx used was 1.3 ml on average (range, 0.2-5.2 ml). All 41 (100 %) parent arteries were successfully occluded. No distal migration of Onyx or coils was noted. Periprocedural complications occurred in 14.6 % (6/41) of cases causing permanent morbidity in 7.3 % (3/41). No patient developed a recurrence during the follow-up period (mean, 14 months). Conclusion: Parent vessel sacrifice with a combination of Onyx and coils appears to be feasible, safe, and effective and may be an alternative to the traditional deconstruction technique with coils alone. The risk of thromboembolism exists with this technique, but there were no instances of Onyx migration. [ABSTRACT FROM AUTHOR]

A new technology and equipment have been developed for a space-saving metallurgical complex designed to efficiently produce up to 50,000-100,000 tons of wire rod a year in the form of 2.5-5.0-ton coils. The new technology is based on the centrifugal continuous casting of 6-12-mm-diam. semifinished products at a speed of 10-25 m/sec. The technology makes it possible to lower unit capital expenditures by a factor of 2.5-3.3 and reduce operating costs by 20-25%. [ABSTRACT FROM AUTHOR]

Background: Coil embolization has gained importance in the management of intracranial aneurysms over the past decade. However, the recurrence risk after embolization mandates closer follow-up than surgical clip ligation. Currently, there is no reliable system for predicting aneurysm sac thrombosis. An aneurysm embolization grade (AEG) reported previously by the senior author (EMD) has been proposed as a tool for predicting the durability of aneurysm occlusion based on hemodynamic characteristics. Here, we present our internal validity results. Methods: AEG and Raymond-Roy Occlusion Classification (RROC) scores were prospectively assigned to all aneurysms coiled from June 2008 to June 2011. The prospectively assigned AEG and RROC scores from the cerebral angiograms were collected for data analysis and validity assessment of the AEG system. 110 consecutive patients who had aneurysm coil embolization were included in this study. Results: The post-coiling AEG significantly predicted follow-up angiographic filling characteristics. Pairwise comparisons revealed that the follow-up AEG for those initially scored 'A' (complete obliteration) was significantly better than the contrast-flow groups. Significant differences were also noted between contrast-stasis and contrast-flow groups. A pairwise comparison between RROC scores demonstrated that only the RROC Type 1 could be used to predict follow-up occlusion durability. Stent placement in wide-neck aneurysms had no effect on initial AEG, RROC, or long-term occlusion durability. Packing density significantly predicted initial AEG and RROC, but had no effect on long-term occlusion. Conclusions: The AEG system is uniquely based on angiographic filling characteristics of the aneurysm, and this study demonstrated its high predictive value for determining aneurysm sac thrombosis. Assigning an AEG to the aneurysm can guide the neurointerventionalist in discussions with the patient regarding the probability of aneurysm recurrence and potential need for retreatment. [ABSTRACT FROM AUTHOR]

In current combined PET/MR systems, PET attenuation correction is based on MRI, since the small bore inside MRI systems and the strong magnetic field do not permit a rotating PET transmission source or a CT device to be integrated. Unlike CT measurements in PET/CT scanners, the MR signal is not directly correlated to tissue density and thus cannot be converted by a simple transformation of intensity values. Various approaches have been developed based on templates, atlas information, direct segmentation of T1-weighted MR images, or segmentation of images from special MR sequences. The advantages and disadvantages of these approaches as well as additional challenges will be discussed in this review. [ABSTRACT FROM AUTHOR]

Shape memory polymer (SMP) foam possesses structural and mechanical characteristics that make them very promising as an alternative treatment for intracranial aneurysms. Our SMP foams have low densities, with porosities as high as 98.8%; favorable for catheter delivery and aneurysm filling, but unfavorable for attenuating X-rays. This lack of contrast impedes the progression of this material becoming a viable medical device. This paper reports on increasing radio-opacity by incorporating a high- Z element, tungsten particulate filler to attenuate X-rays, while conserving similar physical properties of the original non-opacified SMP foams. The minimal amount of tungsten for visibility was determined and subsequently incorporated into SMP foams, which were then fabricated into samples of increasing thicknesses. These samples were imaged through a pig's skull to demonstrate radio-opacity in situ. Quantification of the increase in image contrast was performed via image processing methods and standard curves were made for varying concentrations of tungsten doped solid and foam SMP. 4% by volume loading of tungsten incorporated into our SMP foams has proven to be an effective method for improving radio-opacity of this material while maintaining the mechanical, physical and chemical properties of the original formulation. [ABSTRACT FROM AUTHOR]

Transcatheter closure of patent ductus arteriosus (PDA) with coils is accepted as an alternative to surgical ligation. We evaluated whether flow gradient across PDA, obtained by Doppler echocardiography, can aid in selecting coils for percutaneous ductal occlusion. 79 consecutive patients with PDA, who underwent successful percutaneous coil occlusion were retrospectively reviewed. Patients with other structural heart disease and pulmonary hypertension with right-to-left shunt were excluded. Echocardiogram and cardiac catheterization were done in all patients. Gianturco (Occluding Spring Emboli; Cook, Bloomington, IN) non-detachable coils of 0.038 and 0.052-inch core sizes were used for ductal occlusion. Trough diastolic gradient was correlated with the size and the number of coils used. Mean age was 8.6 years (range 1.3 to 27 years); 24 males and 55 females; PDA diameter ranged from 1.3 to 4.5 mm. Number of coils used varied from 1 to 4. Echocardiography measured PDA size was 2.5 ± 0.6 mm and significantly differed from angiographically measured size 2.9 ± 0.6 mm ( P = 0.05). End diastolic gradient below 38 mmHg predicted use of multiple coils or coils with larger surface area. End diastolic gradient correlated inversely with total surface area of the coils, which indirectly predicted size and number of coils. Thus, the prediction of the size and the number of coils for PDA occlusion can be assisted by the trough diastolic gradients of PDA. [ABSTRACT FROM AUTHOR]

Background: Fusiform aneurysms (FUANs) of vertebrobasilar arterial (VBA) trunk are difficult to treat by using current surgical and endovascular techniques. The objective of this study is to compare the efficacy of FUANs of VBA trunk which was treated with various therapeutic modalities including unilateral or bilateral vertebral artery occlusion, trapping of the aneurysm with coils, stent-assistant coiling, or sole stenting. Methods: Between 2000 and 2008, 17 patients with FUANs (ranged in size from 8 to 45 mm) of VBA trunk in our hospital underwent endovascular treatment in our hospital. Eleven patients were evaluated by test occlusion with nondetachable silicone balloon or hyperglide balloon, and seven patients in this series passed testing with temporary balloon occlusion, among which four patients showed positive result, and three patients were conducted bilateral VA test occlusion. Finally, nine patients underwent a trapping of the aneurysm by coils, four patients were treated with stent-supported coil embolization, and four patients with nonhemorrhagic FUAN of VBA were treated only by stenting. Results: The average imaging follow-up was 28 months, with a range from 6 to 48 months. Fourteen (82%) had excellent or good outcome, three (17.6%) had a poor outcome, and one (5.8%) died. Conclusions: Management of FUANs of VBA trunk often poses difficult therapeutic problems. In some cases, multiple treatment sessions may be not only safe but also necessary for the effective treatment of these aneurysms to achieve a complete or an acceptable result. [ABSTRACT FROM AUTHOR]

To evaluate the feasibility and efficacy of transrenal ureteral occlusion with microcoils in patients with ureterovaginal fistulas Five women (median age 44 years, range 26–51 years) with ureterovaginal fistulas were treated by transrenal ureteral occlusion with microcoils. The underlying diseases were uterine fibroids ( n = 3), a primitive neuroectodermal tumor of the uterine cervix ( n = 1), and an ovarian cancer ( n = 1). Microcoils with or without gelatin sponges, were placed antegradely through a percutaneous nephrostomy (PCN). A PCN tube was then placed to provide an external diversion The transrenal ureteral occlusion was technically successfully in all patients. Complete or near complete (<1 pad/day) dryness was obtained in all patients within 3 days. No complications other than a slight proximal migration of the microcoils in two patients occurred. The PCN tubes were removed in four of the five patients during the follow-up period with the subsequent procedures: antegrade ureteral stent placement, patent normal ureter, an ureteroneocystostomy and a laparoscopic end-to-end anastomosis of the ureter Transrenal ureteral occlusion with microcoils with or without gelatin sponges is a safe and reliable method for the management of patients with ureterovaginal fistulas [ABSTRACT FROM AUTHOR]

It is claimed that bioactive coils induce accelerated and more durable aneurysm healing. Data supporting this claim are quite limited. Our purpose was to compare the angiographic and histological results obtained following treatment with different coil types. Bifurcation type aneurysms were surgically created in 24 dogs and treated using standard clinical techniques. Eight were treated with Guglielmi detachable coils (GDC), eight with first-generation Matrix coils, and eight with a combination of GDC and Matrix coils. The aneurysms were explanted and final angiographic evaluations performed 12 weeks after treatment. Angiographic and histological outcomes were documented. Increased coil compaction with aneurysm recurrence was found in aneurysms treated with first-generation Matrix coils as compared to standard GDC ( P = 0.0001). In aneurysms treated with first-generation Matrix coils thrombus organization was better than in those treated with either standard GDC coils ( P = 0.008) or with a combination of GDC and Matrix coils ( P = 0.04). In aneurysms treated with first-generation Matrix coils there were no endothelialized vascular clefts within the coil mass, but they were seen in the majority of aneurysms treated with GDC or a combination of GDC and Matrix coils ( P = 0.003). Aneurysms treated with first-generation Matrix coils showed the greatest degree of coil compaction and aneurysm recurrence on the final angiographic evaluation. Aneurysms treated with first-generation Matrix coils showed enhanced thrombus organization and absence of vascular clefts at the aneurysm neck that were markedly different from those treated with bare platinum coils or a combination of GDC and Matrix coils. [ABSTRACT FROM AUTHOR]

There is much speculation in reference to the occurrence and mechanisms of progressive aneurysm occlusion after treatment with bioactive coils. However, to our knowledge, there are no studies documenting the impact on progressive occlusion in aneurysms that are intentionally under-packed. A total of 24 experimental side-wall aneurysms were created in canine common carotid arteries. Of these 24, 9 were treated with Guglielmi detachable coils (GDC) and 15 with first-generation Matrix (Matrix1) coils to packing densities of 22% or less. Angiograms were obtained immediately after treatment and again at the time of explant at 2 weeks, 8 weeks, or 12 weeks, and were graded utilizing the Raymond scale. At the time of the final angiography and explant all aneurysms were histologically processed and evaluated. At the conclusion of initial coiling, near or complete occlusion was achieved in 7 of the 15 aneurysms (47%) treated with Matrix1 coils and in 2 of the 9 (22%) treated with GDC. Of the aneurysms that were incompletely occluded, six of eight (75%) treated with Matrix1 coils and two of seven (29%) treated with GDC showed progressive thrombosis at explant. Histopathological analysis demonstrated that the aneurysms treated with Matrix1 coils had increased fibrocellular tissue and inflammation, with less histological recanalization or vascular spaces, relative to those treated with GDC. Experimental wide-necked side-wall canine aneurysms suboptimally treated with first-generation Matrix1 coils had a higher incidence of progressive occlusion and on histological analysis showed evidence of more advanced thrombus organization than did those treated with GDC. [ABSTRACT FROM AUTHOR]

We describe two cases of coil unraveling that occurred during cerebral aneurysm embolization after direct carotid puncture. The unraveled coil was stretched and buried in the subcutaneous part of the neck. No immediate or long-term complication was observed. [ABSTRACT FROM AUTHOR]

Our aim was to conduct a prospective study to evaluate staging accuracy of a new coil concept for endoluminal magnetic resonance imaging (MRI) on ex vivo gastric carcinomas. Twenty-eight consecutive patients referred to surgery with a clinically proven primary gastric malignancy were included. Surgical specimens were examined with a foldable and self-expanding loop coil (8-cm diameter) at 1.5 Tesla immediately after total gastrectomy. T1- and T2-weighted and opposed-phase sequences (axial, frontal sections; 3- to 4-mm slice thickness) were acquired. Investigators blinded to any patient information analyzed signal intensity of normal gastric wall, gastric tumor, and lymph nodes. Findings were compared with histopathological staging. On surgical specimens, 2-5 gastric wall layers could be visualized. All gastric tumors (26 carcinomas, two lymphomas) were identified on endoluminal MR data (100%). Overall accuracy for T staging was 75% (18/24); sensitivity to detect serosal involvement was 80% and specificity 89%. N staging correlated in 58% (14/24) with histopathology (N+ versus N-). The endoluminal coil concept is feasible and applicable for an ex vivo setting. Endoluminal MR data provided sufficient detail for gastric wall layer differentiation, and therefore, identification of T stages in gastric carcinoma is possible. Further investigations in in vivo settings should explore the potential of our coil concept for endoluminal MR imaging. [ABSTRACT FROM AUTHOR]

Recent advancements in endovascular aneurysm repair, including bioactive and expansile coils and intracranial stents, hold promise for improved aneurysm occlusion rates. We report the immediate and midterm clinical and angiographic outcomes of a consecutive series of patients treated since the advent of these technologies. Clinical and radiological records of 134 patients with 142 aneurysms treated between 2001 and 2004 were retrospectively evaluated by an independent neurologist. Endovascular procedures were analyzed by an independent neuroradiologist blinded to all clinical information. Seventy-two ruptured and 60 un-ruptured saccular aneurysms, nine fusiform and one post-traumatic aneurysm were treated. Matrix coils were used in 53% of saccular aneurysms and HydroCoils in 13% of all aneurysms. Neuroform stents were deployed in 19% of aneurysms. Angiographic total or subtotal occlusion was achieved in 76% of cases and in 96% at last follow-up. Aneurysm recanalization was observed in 14% over a mean follow-up of 12 months, and 18% of aneurysms were retreated. Clinically relevant complications occurred in 6.0%, resulting in procedure-related morbidity of 0.6% and 0.6% mortality at 6 months. No aneurysm bled over a cumulative 1,347 months of observation. Newer embolization technologies can be exploited successfully even in more complex aneurysms with very low morbidity and mortality. [ABSTRACT FROM AUTHOR]