[Augmentation in surgical sepsis : Chances and limitations in the treatment of osteitis with calcium hydroxyapatite containing antibiotics]. / Augmentation in der septischen Chirurgie : Chancen und Limitationen in der Behandlung der Osteitis mit antibiotikahaltigem Kalziumhydroxylapatit.

BACKGROUND: The surgical treatment of osteitis or fracture-related infections (FRI) is often associated with large bone defects. The treatment of these defects remains a major challenge in trauma surgery. Within the concept of tissue engineering, the development of various hybrid bone graft substitutes, such as calcium hydroxyapatite with added antibiotics, is continuously progressing. OBJECTIVE: Chances and limitations in the treatment of osteitis with calcium hydroxyapatite containing antibiotics. MATERIAL AND METHODS: Overview of the results of a 2-stage (infection) pseudarthrosis model on rat femurs treated with Cerament® G (Bonesupport, Lund, Schweden). Evaluation of the clinical experiences based on three case examples of osteitis treated with calcium hydroxyapatite containing antibiotics (Cerament® G or Cerament® V). RESULTS: After establishment of a 2­stage pseudarthrosis model on the rat femur, the osteoconductive and osteoinductive potential of calcium hydroxyapatite containing antibiotics could be confirmed. In the clinical application, the use of Cerament® G seems to lead to a more favorable outcome in small cavitary defects. The recurrence rates are higher than previously described, especially for larger segmental defects. CONCLUSION: Taking the clinical and experimental results into consideration, a stricter evaluation of the indications for the use of Cerament® G is necessary to achieve the best possible outcome for patients.

[Artificial intelligence in the management of anti-VEGF treatment: the Vienna fluid monitor in clinical practice]. / Künstliche Intelligenz im Management der Anti-VEGF-Therapie: der "Vienna Fluid Monitor" in der klinischen Praxis.

The Vienna fluid monitor is an artificial intelligence (AI) algorithm for the precise localization and quantification of retinal fluid. The algorithm is designed to help clinicians to make objective and accurate decisions in the anti-vascular endothelial growth factor (anti-VEGF) therapy of patients with neovascular age-related macular degeneration. The goal of the implementation is to optimize patient safety, preserve visual function and simultaneously to reduce the treatment burden on the healthcare system and patients.

Heat dissipation in Sm3+ and Zn2+ co-substituted magnetite (Zn0.1SmxFe2.9-xO4) nanoparticles coated with citric acid and pluronic F127 for hyperthermia application.

In this work, Sm3+ and Zn2+ co-substituted magnetite Zn0.1SmxFe2.9-xO4 (x = 0.0, 0.01, 0.02, 0.03, 0.04 and 0.05) nanoparticles, have been prepared via co-precipitation method and were electrostatically and sterically stabilized by citric acid and pluronic F127 coatings. The coated nanoparticles were well dispersed in an aqueous solution (pH 5.5). Magnetic and structural properties of the nanoparticles and their ferrofluids were studied by different methods. XRD studies illustrated that all as-prepared nanoparticles have a single phase spinel structure, with lattice constants affected by samarium cations substitution. The temperature dependence of the magnetization showed that Curie temperatures of the uncoated samples monotonically increased from 430 to 480 °C as Sm3+ content increased, due to increase in A-B super-exchange interactions. Room temperature magnetic measurements exhibited a decrease in saturation magnetization of the uncoated samples from 98.8 to 71.9 emu/g as the Sm3+ content increased, which is attributed to substitution of Sm3+ (1.5 µB) ions for Fe3+ (5 µB) ones in B sublattices. FTIR spectra confirmed that Sm3+ substituted Zn0.1SmxFe2.9-xO4 nanoparticles were coated with both citric acid and pluronic F127 properly. The mean particle size of the coated nanoparticles was 40 nm. Calorimetric measurements showed that the maximum SLP and ILP values obtained for Sm3+ substituted nanoparticles were 259 W/g and 3.49 nHm2/kg (1.08 mg/ml, measured at f = 290 kHz and H = 16kA/m), respectively, that are related to the sample with x = 0.01. Magnetic measurements revealed coercivity, which indicated that hysteresis loss may represent a substantial portion in heat generation. Our results show that these ferrofluids are potential candidates for magnetic hyperthermia applications.

Correlation of Retinal Thickness and Swept-Source Optical Coherence Tomography Angiography Derived Vascular Changes in Patients with Neovascular Age-Related Macular Degeneration.

Purpose: The aim of this study was to investigate whether structural OCT changes, in specific retinal thickness, is associated with the vascular response within the nAMD CNV lesion. In other words, whether SSOCTA derived parameters may prove suitable to assess CNV activity in future.Methods: During the first 3 months patients were prospectively followed with visits at days 7, and 14 after each anti-VEGF treatment up to day 90. At baseline, day 30 and 60 Aflibercept was administered. OCT-derrived retinal thickness (RT) and OCTA-derived CNV lesion parameters (vessel area [VA]), total vessel length [TVL], total number of junctions [TNJ], junction density [JD]) were determined. Parameters were exported from SSOCT/A (PlexElite, Zeiss) images using the semi-automated AngioTool software. Additionally, the superficial and deep vascular plexus fractal dimension of the para- and perifoveal region were identified. Consequently, all OCTA derived parameters were correlated with RT.Results: 16 consecutive patients presenting with treatment-naïve, SSOCTA-positive CNV lesions were included. A weak to moderate statistically significant correlation was found between the mean RT of the inner as well as the outer ETDRS ring with the SSOCTA-derived vascular markers vessel area (VA; r2 = -0.38, p < .001; r2 = -0.47, p < .001, respectively), total vessel length, (TVL; r2 = -0.38, p < .001; r2 = -0.48, p < .001, respectively) and total number of junctions (TNJ; r2 = -0.35, p < .001; r2 = -0.44, p < .001, respectively). Junctions density (JD), and all variables based on fractal dimension (FD) did not show statistically significant correlations with retinal thickness measurements.Conclusions: In summary, we could confirm a moderate, however, statistically significant correlation between mean para- and perifoveal retinal thickness and the SSOCTA derived vascular parameters VA, TVL, and TNJ. This leads us to the conclusion that an SSOCTA-based activity analysis of the CNV complex is not yet a substitute for retinal thickness or in-depth fluid analysis in patients with nAMD.

[Cardiac magnetic resonance imaging : Trends and developments]. / Kardiale Magnetresonanztomographie : Trends und Entwicklungen.

BACKGROUND: In its almost 25 years of clinical use, cardiac magnetic resonance imaging (CMR) has been developed for a wide range of indications due to the development of robust techniques and their comprehensive validation. CMR-based assessment of cardiac volumes and systolic ventricular function as well as the characterization of focal myocardial scars belongs today to standard cardiac imaging. More recently, the introduction of accelerated acquisition techniques, quantitative myocardial T1- and T2-mapping methods and 4­dimensional (4D) flow measurements as well as new postprocessing techniques such as myocardial feature tracking have attracted attention. METHODS: This review is based on a comprehensive literature search in the PubMed database on new CMR techniques and their clinical application. RESULTS AND CONCLUSION: This article provides an overview of the latest technical developments in the field of CMR and their possible applications based on the most important clinical MR issues.

Dilated Epidural Venous Plexus Causing Radiculopathy: A Report of 2 Cases and Review of the Literature.

BACKGROUND: A dilated epidural venous plexus (DEVP) is a rare cause of radiculopathy, back pain, cauda equina syndrome, and other neurological symptoms. This vascular mass can be secondary to inferior vena cava obstruction, portal hypertension, vascular agenesis, and hypercoagulable states. Although rare, DEVP should be considered in the differential diagnosis for patients who present with lumbar radiculopathy. CASE DESCRIPTION: We present 2 cases involving patients with lumbar DEVP as well as a literature review of the role of hypercoagulability, vascular anatomy, and inferior vena cava thrombosis in the development of DEVP. The first patient had a history of recurrent deep vein thrombosis, systemic lupus erythematosus, and antiphospholipid syndrome. The diagnosis of DEVP was determined after intraoperative biopsy. The patient reported symptom resolution at her 6-month postoperative appointment. The second patient developed DEVP associated with Klippel-Trenaunay syndrome. She presented with back pain and leg weakness, and DEVP was diagnosed via magnetic resonance imaging. A neurosurgeon is currently following the patient. We believe this is the first case of Klippel-Trenaunay syndrome associated with DEVP. CONCLUSIONS: If a patient presents with an enhancing epidural lesion on magnetic resonance imaging and neurological symptoms, DEVP should be considered in the differential diagnosis. Additionally, a search for inferior vena cava thrombosis should be performed as well as risk factors for venous hypertension and hypercoagulable states.

[Options for soft tissue reconstruction in pseudarthrosis]. / Möglichkeiten der Weichteilrekonstruktion bei Pseudarthrosen.

BACKGROUND: Pseudarthrosis can develop as a complication after conservative or operative fracture treatment and after elective orthopedic surgery. The treatment is challenging and is made more difficult when accompanied by large soft tissue defects or impairments in wound healing. In this case close and early coordination between trauma and plastic surgeons is crucial in order to develop a coherent and interdisciplinary treatment plan. METHODS: Due to the positive effects on bone consolidation and osteomyelitis, timely soft tissue reconstruction via a pedicled vascularized flap or free flap coverage should be preferred. If blood circulation in the affected extremity appears to be compromised, this should first be optimized by vascular intervention or bypass surgery. In atrophic, aseptic pseudarthrosis, bone and soft tissue reconstruction can be performed consecutively in one single procedure, whereas septic pseudarthrosis always require complete resection of all infected debris prior to wound closure. Examples of two commonly used free flaps are the latissimus dorsi muscle flap and the fasciocutaneous anterolateral thigh (ALT) flap. As multiple variations have been described for both procedures, the reconstructive portfolio lists many additional options available for soft tissue reconstruction. Fasciocutaneous flaps should be preferred whenever bone consolidation requires additional surgical interventions in the future.

Non-Union After Multiple Lumbar Fusion Surgeries in a Patient With Facioscapulohumeral Muscular Dystrophy: A Case Report and Review of the Literature.

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is a rare condition affecting 1/20,000 persons and the third most common muscular dystrophy condition, with an autosomal dominant pattern of inheritance characterized by progressive muscular weakness primarily involving the face, shoulder girdle, and upper arm. The condition is associated with atrophic musculature of the trunk and core leading to difficulties with gait, posture, and function. FSHD leaves as many as 20% of patients wheelchair-bound and most commonly presents with low back, neck, and shoulder pain. CASE DESCRIPTION: We present the case of a patient with FSHD who underwent multiple spinal fusion surgeries without relief in her back pain. Imaging studies serve to highlight the extent of paraspinal muscle atrophy and provides the basis for a discussion on the preoperative factors that may predict patients most likely to benefit from surgery. We then provide a brief review of the literature on the role of paraspinal muscle atrophy in back pain. CONCLUSIONS: This case adds to our understanding of the surgical management of patients with FSHD and patients with atrophic core musculature as a whole.

[Reconstruction of lower limbs in old age-an interdisciplinary approach : Strategies for trauma surgery, vascular surgery and plastic surgery]. / Rekonstruktion der unteren Extremität im Alter ­ ein interdisziplinärer Ansatz : Unfallchirurgische, gefäßchirurgische und plastisch-chirurgische Strategien.

The treatment of complex injuries of the lower extremities in geriatric and/or multimorbid patients requires optimized preoperative and perioperative management as well as differentiated and interdisciplinary surgical approaches. Timely and definitive treatment should be strived for to avoid longer periods of immobilization. Temporary external stabilization of complex fractures, when necessary, should be followed by permanent loading stable internal osteosynthesis as soon as possible. Accompanying soft tissue defects are reconstructed after wound débridement using the full armamentarium of plastic and reconstructive surgical procedures, including microvascular free flap. In the context of perfusion compromised soft tissue situations, negative pressure wound therapy can provide sterile temporary defect coverage and aid in preconditioning poorly vascularized tissue before definitive reconstruction. A clarification of the vascular status in geriatric patients is paramount and relevant perfusion disorders should be treated either by intervention or open surgery before complex reconstructive interventions. Close interdisciplinary coordination of the various surgical procedures is imperative in order to guarantee an optimized stable reconstructive outcome with acceptable patient risk. Taking these principles into account, the reconstruction of complex trauma to the extremities can be carried out even in geriatric or multimorbid patients in specialized interdisciplinary surgical centers with excellent functional results.

[Reconstruction of lower limbs in old age-an interdisciplinary approach : Geriatric assessment, perioperative management, diagnostics and treatment targets]. / Rekonstruktion der unteren Extremität im Alter ­ ein interdisziplinärer Ansatz : Geriatrisches Assessment, perioperatives Management, Diagnostik und Therapieziele.

Complex injuries of the lower extremities in geriatric patients with multiple pre-existing comorbidities represent an increasing challenge to an interdisciplinary team of surgeons. Functional reconstruction of the extremity through osteosynthesis, revascularization and defect coverage aims to preserve mobility and achieve an early return to activities of daily life at home, while avoiding major amputation and the associated risks regarding morbidity and mortality. An interdisciplinary assessment of geriatric patients regarding dystrophy of soft tissue and skín, cardiovascular and metabolic comorbidities as well as specific geriatric diagnostics are crucial steps in ensuring favorable outcomes. Perioperatively, all improvable risk factors should be actively optimized and a specialized interdisciplinary approach to treatment planning (extremity board) is absolutely necessary for success of treatment. It outlines the special features of the geriatric assessment, diagnostics, perioperative management and treatment targets.

Multiple Structural Transitions in Langmuir Monolayers of Charged Soft-Shell Nanoparticles.

We have investigated the morphologies of Langmuir layers of charged, polymeric hard-core/interlayer/soft-shell nanoparticles spread at the air-water interface. Depending on various mutual interactions, which are correlated to the areal densities of the deposited nanoparticles, we observed ordered patterns of nondense and closed-packed arrangements of core/interlayer/shell (CIS) nanoparticle ordering. At low areal densities, we found an almost regular distribution of the charged CIS nanoparticles on the water surface, which resulted from long-range repulsive electrostatic interactions between them. At higher areal densities, domains of more closely packed and ordered nanoparticles were formed, coexisting with regions of randomly and sparsely distributed nanoparticles. We relate these domains to the interplay of electrostatic repulsion and capillary attraction caused by the dipolar character of like-charged particles at the interface, allowing for a characteristic separation distance between nanoparticles of about 3-4 times the nanoparticle diameter. At relatively high areal densities, attractive van der Waals forces were finally capable of making nanoparticles to come in contact with each other, leading to densely packed patches of hexagonally ordered nanoparticles coexisting with regions of rather well-ordered nanoparticles separated by about 1 µm and regions of randomly and sparsely distributed nanoparticles. Intriguingly, upon re-expansion of the area available per nanoparticle, these densely packed patches disappeared, indicating that steric repulsion due to the presence of soft shells as well as long-range electrostatic repulsive forces were strong enough to assure reversibility of the morphological behavior.

A novel interferometric method for the study of the viscoelastic properties of ultra-thin polymer films determined from nanobubble inflation.

Glass formation and glassy behavior remain as the important areas of investigation in soft matter physics with many aspects which are still not completely understood, especially at the nanometer size-scale. In the present work, we show an extension of the "nanobubble inflation" method developed by O'Connell and McKenna [Rev. Sci. Instrum. 78, 013901 (2007)] which uses an interferometric method to measure the topography of a large array of 5 µm sized nanometer thick films subjected to constant inflation pressures during which the bubbles grow or creep with time. The interferometric method offers the possibility of making measurements on multiple bubbles at once as well as having the advantage over the AFM methods of O'Connell and McKenna of being a true non-contact method. Here we demonstrate the method using ultra-thin films of both poly(vinyl acetate) (PVAc) and polystyrene (PS) and discuss the capabilities of the method relative to the AFM method, its advantages and disadvantages. Furthermore we show that the results from experiments on PVAc are consistent with the prior work on PVAc, while high stress results with PS show signs of a new non-linear response regime that may be related to the plasticity of the ultra-thin film.

Blocking of injected holes at the charge extracting interface.

For an organic crystal with four metal electrodes, we have investigated the charge transfer between the injecting electrode 1 and the extracting electrodes 2-4. Each of the measured I-V curves was decomposed into three components, characterizing the injecting and extracting interfaces, and the squaraine (SQ) crystal. We considered a case, where the resistance of the organic crystal was significantly smaller than that of the interfaces. The different values of the contact resistances measured at different electrodes are related to differing values of the barrier height [Formula: see text] and its width d, which were determined using the Simmons approximation. When the extracting interface has a larger contact resistance compared to that of the SQ crystal and that of the injecting interface, part of the injected holes remains located within the SQ crystal. The voltage V 0, at which the injected hole density begins to exceed the extracted hole density within the SQ crystal, depends on the ratio [Formula: see text] (indices ex and in describe the extracting and injecting electrodes, respectively). The smaller δ is, the larger is voltage V 0.

Automated two-point dixon screening for the evaluation of hepatic steatosis and siderosis: comparison with R2-relaxometry and chemical shift-based sequences.

OBJECTIVES: To evaluate the automated two-point Dixon screening sequence for the detection and estimated quantification of hepatic iron and fat compared with standard sequences as a reference. METHODS: One hundred and two patients with suspected diffuse liver disease were included in this prospective study. The following MRI protocol was used: 3D-T1-weighted opposed- and in-phase gradient echo with two-point Dixon reconstruction and dual-ratio signal discrimination algorithm ("screening" sequence); fat-saturated, multi-gradient-echo sequence with 12 echoes; gradient-echo T1 FLASH opposed- and in-phase. Bland-Altman plots were generated and correlation coefficients were calculated to compare the sequences. RESULTS: The screening sequence diagnosed fat in 33, iron in 35 and a combination of both in 4 patients. Correlation between R2* values of the screening sequence and the standard relaxometry was excellent (r = 0.988). A slightly lower correlation (r = 0.978) was found between the fat fraction of the screening sequence and the standard sequence. Bland-Altman revealed systematically lower R2* values obtained from the screening sequence and higher fat fraction values obtained with the standard sequence with a rather high variability in agreement. CONCLUSIONS: The screening sequence is a promising method with fast diagnosis of the predominant liver disease. It is capable of estimating the amount of hepatic fat and iron comparable to standard methods. KEY POINTS: • MRI plays a major role in the clarification of diffuse liver disease. • The screening sequence was introduced for the assessment of diffuse liver disease. • It is a fast and automated algorithm for the evaluation of hepatic iron and fat. • It is capable of estimating the amount of hepatic fat and iron.

Anomalous ground state of the electrons in nanoconfined water.

Water confined on the scale of 20 Å, is known to have different transport and thermodynamic properties from that of bulk water, and the proton momentum distribution has recently been shown to have qualitatively different properties from that exhibited in bulk water. The electronic ground state of nanoconfined water must be responsible for these anomalies but has so far not been investigated. We show here for the first time, using x-ray Compton scattering and a computational model, that the ground state configuration of the valence electrons in a particular nanoconfined water system, Nafion, is so different from that of bulk water that the weakly electrostatically interacting molecule model of water is clearly inapplicable. We argue that this is a generic property of nanoconfinement. The present results demonstrate that the electrons, and hence the protons as well, of nanoconfined water are in a distinctly different quantum state from that of bulk water. Biological cell function must make use of the properties of this state and cannot be expected to be described correctly by empirical models based on the weakly interacting molecules model.

[Clinical relevance and indications for cardiac magnetic resonance imaging 2013: an interdisciplinary expert statement]. / Klinischer Stellenwert und Indikationen zur Magnetresonanztomografie des Herzens 2013: Ein interdisziplinäres Expertenstatement.

During the last years the indications of Cardiac Magnetic Resonance Imaging (CMRI) have been continuously expanded. However, the acceptance of the method by cardiologists and radiologists does not correlate with respect to the diagnostic potential. Several factors, such as expensive equipment, relatively long examination times, high technical know how and lack of remuneration, limit the application of CMRI in everyday clinical practice. Furthermore, doctors tend to apply more conventional, well established diagnostic procedures, the access to the method is still limited and there exist difficulties in the interdisciplinary collaboration. The interdisciplinary Austrian approach to Cardiac Imaging is aimed to improve the aforementioned problems and to support the implementation of CMRI in the diagnostic tree of cardiac diseases thus enabling a cost efficient management of patients in cardiology.

Functionalized cyclodextrins bearing an alpha nucleophile--a promising way to degrade nerve agents.

Organophosphorus nerve agents are irreversible inhibitors of acetylcholinesterase. Current treatment of nerve agent poisoning has limited efficacy and more efficient medical countermeasures need to be developed. A promising approach is to design chemical scavengers more stable during storage and less immunogenic than bioscavengers. Furthermore, they could be produced at lowest production costs. Cyclodextrins are attractive cyclic oligosaccharides that can be used to develop chemical scavengers of organophosphorus nerve agents. Their abilities to form inclusion and non-inclusion complexes with organic substrates are useful to trap chemical warfare agents. Selective introduction of an α-nucleophile residue on the secondary face of ß-cyclodextrin allowed to obtain supramolecular derivatives active against organophosphorus compounds. The degradation activity of these monosubstituted cyclodextrins was determined against paraoxon and chemical warfare agents. These tests showed that the structure of the scavengers mainly influences the interaction between the organophosphorus substrate, or its reaction products, and the cyclodextrin moiety. All the tested G-type agents were efficiently degraded. According to the binding modes of cyclosarin, some oligosaccharidic scavengers led to an enantioselective degradation of this nerve agent. These promising derivatives open the way to further investigations of new structural modifications to reach more sophisticated and efficient scavengers for prophylactic and curative medical applications.

[The new S2k AWMF guideline for the treatment of Bell's palsy in commented short form]. / Die neue S2k AWMF Leitlinie zur idiopathischen Fazialisparese in kommentierter Kurzform.

A new S2k AWMF guideline for the treatment of idiopathic facial palsy has been published. An accurate differential diagnosis is indispensable as 25-40% of all facial palsy cases are of non-idiopathic origin. It is explicitly recommended to treat patients with idiopathic facial palsy with steroids. Steroids favour a complete recovery, decrease the risk of synkinesis, autonomic sequelae and contractures. Adjuvant antiviral therapy cannot be recommended. On current data there is not sufficient evidence that the combination of steroids with antiviral drugs has a benefit for the patients. Even when not supported by randomized trials, adjuvant symptomatic therapy to protect the cornea and to avoid complications is recommended. There is no scientific evidence that physical therapy has any benefit but it should be taken into account because of psychological reasons. A benefit of acupuncture has not been proven. If eye closure remains incomplete as result of defective healing, one therapeutic option is lid loading of the upper eye lid. Moreover, in case of severe persistent palsy, several well-established microsurgical nerve and muscle plasty procedures are available.

Morphological changes during annealing of polyethylene nanocrystals.

Polymer crystals are metastable and exhibit morphological changes when being annealed. To observe morphological changes on molecular scales we started from small nanometer-sized crystals of highly folded long-chain polymers. Micron-sized stripes consisting of monolayers or stacks of several layers of flat-on oriented polyethylene nanocrystals were generated via evaporative dewetting from an aqueous dispersion. We followed the morphological changes in time and at progressively higher annealing temperatures by determining the topography and viscoelastic properties of such assemblies of nanocrystals using atomic force microscopy. Due to smallness and high surface-to-volume ratio of the nanocrystals, already at 75 °C, i.e. about 60 degrees below the nominal melting point, the lateral size of the crystal coarsened. Intriguingly, this occurred without a noticeable reduction in the number of folds per polymer chain. Starting at around 110 °C, chain folds were progressively removed leading to crystal thickening. At higher temperatures, but still below the melting point, prolonged annealing allowed for surface diffusion of molten polymers on the initially bare substrate, leading eventually to the disappearance of crystals. We compared these results to the behavior of the same nanocrystals annealed in an aqueous dispersion and to bulk samples.