Three-Dimensional Analysis of the In Vivo Motion of Implantable Cardioverter Defibrillator Leads.

Unlabelled: Better understanding of the lead curvature, movement and their spatial distribution may be beneficial in developing lead testing methods, guiding implantations and improving life expectancy of implanted leads.

Objective: The aim of this two-phase study was to develop and test a novel biplane cine-fluoroscopy-based method to evaluate input parameters for bending stress in leads based on their in vivo 3D motion using precisely determined spatial distributions of lead curvatures. Potential tensile, compressive or torque forces were not subjects of this study.

Not Recommended, But Done: Breastfeeding with HIV in Germany.

Breastfeeding (BF) in mothers living with HIV (MLWH) is still discussed controversially in resource-rich settings. In Germany, where formula feeding is recommended for MLWH single BF cases have been reported, but no systematic data collection and analysis are available so far. This study, titled HELENE, aims to fill this data gap.

Planar Tetracoordinated Silicon (ptSi): Room-Temperature Stable Compounds Containing Anti-van't Hoff/Le Bel Silicon.

While a variety of compounds containing planar tetracoordinated carbon (ptC), the so-called anti-van't Hoff/Le Bel carbon, are known experimentally, stable systems containing planar tetracoordinated silicon (ptSi) are barely known. As part of our studies on the application of stereoelectronically well-defined transition-metal fragments to stabilize silicon in unprecedented bonding modes, we report herein the synthesis and full characterization of a series of thermally stable complexes of the general formula [Tp'(CO)MSiC(R)C(R)M(CO)Tp'] (M = Mo, W; R = R = Me or R = H, R = SiMe, Ph; Tp' = κ-,',″-hydridotris(3,5-dimethylpyrazolyl)borate), which incorporate a ptSi atom in addition to two ptC atoms. The complexes were obtained by reacting the metallasilylidyne complexes [Tp'(CO)M≡Si-M(CO)(PMe)Tp'] with alkynes RC≡CR and were comprehensively analyzed by experimental studies and quantum chemical calculations.

MR-Guided Percutaneous Intradiscal Thermotherapy (MRgPIT): Evaluation of a New Technique for the Treatment of Degenerative Disc Disease in Cadaveric Lumbar Spine.

Purpose: Evaluation of MR feasibility and real-time control of an innovative thermoablative applicator for intradiscal thermotherapy and histological analysis of laser annuloplasty in human ex vivo intervertebral discs.

Materials And Methods: We evaluated a new MR-compatible applicator system for MR-guided percutaneous intradiscal thermotherapy (MRgPIT) in an open 1.0-T MRI-system.

[Parsonage-Turner Syndrome - Case Report].

Neuralgic amyotrophy of the shoulder (Parsonage-Turner syndrome) is a rare condition of unknown aetiology which manifests as acute neuropathy of the brachial plexus. Diagnosis is based on typical symptoms and physical examination. In addition, magnetic resonance imaging of the affected shoulder and the cervical spine is advisable, in order to distinguish this syndrome from other conditions with similar symptoms.

MRI-guided percutaneous transhepatic cholangiodrainage: feasibility study in a porcine model.

Background And Study Aims: MRI-guided procedures combine high-quality imaging with lack of radiation. Percutaneous transhepatic cholangiodrainage under real-time MRI guidance (MRI-PTCD) seems promising, allowing targeted puncture and avoiding multiple blind passes and use of contrast, which are associated with standard PTCD's heaviest complications.

Patients And Methods: Aim of this study was to investigate the feasibility of MRI-PTCD in three outbred piglets.

Comparison of four radiofrequency ablation systems at two target volumes in an ex vivo bovine liver model.

Purpose: We aimed to validate actually achieved macroscopic ablation volumes in relation to calculated target volumes using four different radiofrequency ablation (RFA) systems operated with default settings and protocols for 3 cm and 5 cm target volumes in ex vivo bovine liver.

Materials And Methods: Sixty-four cuboid liver specimens were ablated with four commercially available RFA systems (Radionics Cool-tip, AngioDynamic 1500X, Boston Scientific RF 3000, Celon CelonPower LAB): 16 specimens for each system; eight for 3 cm, and eight for 5 cm. Ablation diameters were measured, volumes were calculated, and RFA times were recorded.

Ankle laxity: stress investigation under MRI control.

Objective: The purpose of this study was to examine the advantages of MRI-guided ankle stress examinations in the detection of chronic ankle instability.

Subjects And Methods: An MRI-compatible stress device was developed and tested for MRI safety. Bilateral MRI stress examinations were performed on 50 volunteers with and without clinically evident subjective instability of the ankle joints (72 subjective stable ankle joints in 37 subjects, 28 ankles in 15 subjects with chronic ankle instability).

Pathogenesis and treatment of HIV infection: the cellular, the immune system and the neuroendocrine systems perspective.

Infections with HIV represent a great challenge for the development of strategies for an effective cure. The spectrum of diseases associated with HIV ranges from opportunistic infections and cancers to systemic physiological disorders like encephalopathy and neurocognitive impairment. A major progress in controlling HIV infection has been achieved by highly active antiretroviral therapy (HAART).

Real-time MR-guided lumbosacral periradicular injection therapy using an open 1.0-T MRI system: an outcome study.

Objectives: The objective of this study was to evaluate the accuracy, safety, and efficacy of magnetic resonance (MR)-guided periradicular nerve root injection therapy using an open 1.0-T magnetic resonance imaging (MRI) system with fast dynamic imaging.

Materials And Methods: Between April 2008 and November 2011, a total of 249 MR-guided periradicular nerve root injections were performed in 141 patients experiencing lumbosacral radicular pain.

Magnetic resonance imaging of the active second stage of labour: proof of principle.

Objective: To prove that magnetic resonance imaging of foetal anatomy during the active second stage of vaginal delivery is feasible.

Materials And Methods: Initially, five pregnant volunteers around the 30th week of gestation were examined in an open MRI. Based on the findings, one vaginal delivery was acquired under real-time imaging.

Evaluation of a MR-quadrupole imaging coil for spinal interventions in a vertical 1.0 T MRI.

The in vivo pain treatment was successfully performed with the patient in a prone position. The PD-weighted TSE with echo time = 10 ms rendered contrast-to-noise-ratio values of 27 ± 10 for needle/fat, 1.6 ± 5 for needle/muscle, and 4 ± 4.

Genetic CD21 deficiency is associated with hypogammaglobulinemia.

Background: Complement receptor 2 (CR2/CD21) is part of the B-cell coreceptor and expressed by mature B cells and follicular dendritic cells. CD21 is a receptor for C3d-opsonized immune complexes and enhances antigen-specific B-cell responses.

Objective: Genetic inactivation of the murine CR2 locus results in impaired humoral immune responses.

A signal-inducing bone cement for magnetic resonance imaging-guided spinal surgery based on hydroxyapatite and polymethylmethacrylate.

The aim of this study was to develop a signal-inducing bone cement for magnetic resonance imaging (MRI)-guided cementoplasty of the spine. This MRI cement would allow precise and controlled injection of cement into pathologic lesions of the bone. We mixed conventional polymethylmethacrylate bone cement (PMMA; 5 ml methylmethacrylate and 12 g polymethylmethacrylate) with hydroxyapatite (HA) bone substitute (2-4 ml) and a gadolinium-based contrast agent (CA; 0-60 μl).

Percutaneous transhepatic cholangiodrainage under real-time MRI guidance: initial experience in an animal model.

Aims: To assess percutaneous transhepatic cholangiodrainage (PTCD) under real-time MRI-guidance and compare it to procedures performed under fluoroscopy.

Methods: We developed an in vitro model for MRI-guided and conventional PTCD, using an animal organ set including liver and bile ducts placed in an MRI-compatible box and tested it in a 1.0-Tesla open MRI-scanner.

Reduced k-space acquisition to accelerate MR imaging of moving interventional instruments: a phantom study.

Purpose: The goal of this study was to investigate the impact of reduced k-space sampling rates on the visualization of a moving MR-compatible puncture needle and to demonstrate the feasibility of keyhole imaging in interventional magnetic resonance imaging (MRI).

Material And Methods: All experiments were performed in an open 1.0 Tesla MRI.

Minimally invasive magnetic resonance imaging-guided free-hand aspiration of symptomatic nerve route compressing lumbosacral cysts using a 1.0-Tesla open magnetic resonance imaging system.

Purpose: To evaluate the feasibility of minimally invasive magnetic resonance imaging (MRI)-guided free-hand aspiration of symptomatic nerve route compressing lumbosacral cysts in a 1.0-Tesla (T) open MRI system using a tailored interactive sequence.

Materials And Methods: Eleven patients with MRI-evident symptomatic cysts in the lumbosacral region and possible nerve route compressing character were referred to a 1.

The impact of imaging speed of MR-guided punctures and interventions in static organs--a phantom study.

Purpose: Verification of MR-guidance with image acquisitions slower than 1 image per second as it is inevitable for some interventions. Therefore, we quantified solely the effect of acquisition-time on the efficiency of MR-guided interventions in a static phantom study.

Materials And Methods: We measured the duration, accuracy and error rate of simulated interventions for different acquisition-times using a simplified interventional setup.

Obese patients in an open MRI at 1.0 Tesla: image quality, diagnostic impact and feasibility.

Objective: To investigate the performance of an open MRI system at its conceptual limits by examining excessively obese patients who otherwise could not receive adequate imaging examinations.

Methods: Twenty-six excessively obese patients (BMI ≥ 35, average age 46) where CT, standard MR or ultrasound examinations were not possible or not conclusive were referred to an open MRI system at 1.0 Tesla.

[A wireless communication system for interventional MRI].

The available MR-compatible communication systems, which are typically designed for diagnostic exams, are mostly based on tubular sound transmission. In other settings, modern commercially available communication systems with ear protection allow wireless communication in noisy environments. The application of MR-compatible wireless headsets in interventional radiology precludes tube contact with sterile surfaces and hindrance of the interventionalist's range of motion.

[Conception and course of eight pregnancies in five women on TNF blocker etanercept treatment].

The introduction of tumor necrosis factor (TNF)-α inhibitors s in the late 1990s considerably broadened the treatment options for, and essentially contributed to the successful management of, rheumatoid arthritis (RA) and other immune-mediated inflammatory diseases. Nevertheless, their use during pregnancy is still controversially discussed since it remains unclear whether the benefits of treatment might be outweighed by potential teratogenicity or adverse effects on the course of pregnancy. In this case series report we describe the course and outcome of eight pregnancies in five women (four with RA and one with ankylosing spondylitis) at our private clinical practice treated with the TNF-α inhibitor etanercept at the time of conception and during pregnancy.

Laser-induced thermotherapy (LITT)--evaluation of a miniaturised applicator and implementation in a 1.0-T high-field open MRI applying a porcine liver model.

Objective: To evaluate the feasibility and safety of a novel LITT applicator for thermal ablation of liver malignancies in 1.0-T high-field open MRI.

Methods: A miniaturised 6-F double-tubed protective catheter with a closed cooling circuit was used with a flexible laser fibre, connected to a 1,064-nm Nd:YAG laser and evaluated in non-perfused porcine livers (18-30 W for 10-20 min, 2-W and 2-min increments; n = 210/applicator) in reference to an established 9-F system.

Intradiscal temperature monitoring using double gradient-echo pulse sequences at 1.0T.

Purpose: To validate an unspoiled gradient-recalled echo pulse sequence with dual echo acquisition as a means to increase temperature sensitivity while monitoring intradiscal laser ablation therapy.

Materials And Methods: Phantom experiments as well as in vitro thermal ablation simulations were performed in an open 1.0T magnetic resonance (MR) scanner.

Advancements in orthopedic intervention: retrograde drilling and bone grafting of osteochondral lesions of the knee using magnetic resonance imaging guidance.

Computer-assisted surgery is currently a novel challenge for surgeons and interventional radiologists. Magnetic resonance imaging (MRI)-guided procedures are still evolving. In this experimental study, we describe and assess an innovative passive-navigation method for MRI-guided treatment of osteochondritis dissecans of the knee.

Evaluation of thermometric monitoring for intradiscal laser ablation in an open 1.0 T MR scanner.

Purpose: The purpose of this study was to evaluate different methods of magnetic resonance thermometry (MRTh) for the monitoring of intradiscal laser ablation therapy in an open 1.0 Tesla magnetic resonance (MR) scanner.

Material And Methods: MRTh methods based on the two endogenous MR temperature indicators of spin-lattice relaxation time T1 and water proton resonance frequency (PRF) shift were optimised and compared in vitro.