[Thyroid cartilage fracture following sneezing as a cause of spontaneous pneumomediastinum]. / Perelom shchitovidnogo khryashcha vsledstvie chikhan'ya kak prichina spontannogo pnevmomediastinuma.

OBJECTIVE: To evaluate the possible etiological factors of spontaneous pneumomediastinum and to describe a case that was unusual in its etiology: a thyroid cartilage fracture as a result of sneezing. MATERIAL AND METHODS: Six patients (four male, two female, aged 16-82 years) were hospitalized with spontaneous pneumomediastinum diagnosed with a chest X-ray in five patients and 100% with computed tomography. Treatment was symptomatic. RESULTS: The commonest symptoms (cough, shortness of breath, hoarseness) were in four patients. Spontaneous pneumomediastinum developed in three cases as a result of bronchospasm during an attack of bronchial asthma, in one patient after exercise, in one after fibrogastroscopy, in one after sneezing. We report a 30-year-old man who presenting subcutaneous emphysema on the neck, hoarseness, pain when swallowing, hemoptysis developed after sneezing. His computed tomography revealed a pneumomediastinum due to fistula of the fracture of the thyroid cartilage following sneezing while simultaneously obstructing both nostrils. At laryngoscopy, there was a linear hematoma in the resolution stage on the anterior wall of the larynx. He was treated conservatively and recovered rapidly. There are no previous published reports of spontaneous pneumomediastinum following fracture of the thyroid cartilage. CONCLUSION: Fracture of the thyroid cartilage as a result of a sharp rapid increase in airway pressure during a sneeze with blocked nasal passages can be one of the rare causes of spontaneous pneumomediastinum. Avoid closing both nostrils at the same time when sneezing.

The Impact of a Robotic Digital Microscope on the Ergonomics in a Neurosurgical Operating Theatre (A Single-Centre Experience).

Ergonomics is an emerging concept in the neurosurgical operating theatre, where neurosurgeons work under great concentration and frequently neglect their uncomfortable body posture. Work-related musculoskeletal disorders (WMSD) are becoming a widespread burden in the neurosurgical community. WMSD have a negative impact on surgical performance and decrease the surgeons' quality of life. Here we present our single-centre 2-month experience with the Aesculap AEOS® Robotic Digital Microscope (RDM) and prospectively calculate the REBA (Rapid Entire Body Assessment) scores and compare them with similar neurosurgical cases operated with a conventional operative microscope (OPMI).Materials and Methods: For a period of 2 months at the Department of Neurosurgery of the University Hospital Pirogov, Sofia, Bulgaria, 41 consecutive patients were operated on using RDM. The REBA employee assessment worksheets were filled in prospectively to assess the ergonomics of the senior author (N.G.) while using the RDM and the OPMI.Results and Conclusion: The ergonomics during neurosurgical operations could be substantially improved with the implementation of the exoscope. For challenging cranial approaches, where the operator must frequently "look around corners" the exoscope has a major advantage compared with the OPMI-the REBA score is 2.6 times lower for the exoscope and reaches a low risk for WMSD. For spinal operations, the neck score as part of the REBA score is three times lower for the exoscope.

Development and testing of secondary ion accelerator for ITER neutral particle diagnostic system.

This paper presents the results of the development and testing of a secondary ion accelerator for the diagnostic complex of neutral particle analyzers at ITER. The accelerator is part of an analyzer designed to measure fluxes of neutral deuterium and tritium particles escaping from reactor plasma in a total range of 10-200 keV. The aim of the accelerator is to improve the signal/background ratio of the analyzer. It is especially important for the region with a relatively low energy of 10-50 keV. The accelerator has the function of converting atoms into secondary ions and accelerating them in an electrostatic field with a voltage of up to +100 kV. The accelerator is based on two high-voltage accelerating tubes. A special unit is built into the central electrode of the accelerator, which provides the replacement of stripping foils used for the conversion of the flux of neutral particles into a flux of secondary ions. The high-voltage tube assembly is encompassed by a sealed steel housing, in which electrical insulation is provided by a gas gap (nitrogen at 6 bar). The results of tests of the accelerator under ITER relevant conditions, namely, under high-intensity gamma irradiation and seismic loads, have shown its high reliability for use in the diagnostic complex of the fusion reactor.

Bilateral posterior fracture - dislocation of the shoulders after epileptic seizure in patients with cerebral meningiomas. Triple E syndrome - Review of the literature.

Bilateral posterior fracture-dislocation of the shoulders is a very rare entity with an average rate of 0.6/100000 per year. It was first described in 1902 by Mynter. Only a few cases have been published so far. The "triple E syndrome" is used to describe the causative factors involved in this injury - epilepsy, electrocution, extreme trauma. We present our experience since 2019 with 2 cases of bilateral posterior fracture-dislocation of the shoulders after an epileptic seizure in patients with cranial meningiomas. Total removal of the meningiomas was performed in both cases and afterwards the patients were operated on by the traumatology team. The shoulder joint is the most commonly dislocated joint in the body with less than 4 % being posteriorly dislocated. Bilateral fracture-dislocation of the shoulders is associated with "triple E syndrome" and 90 % of the cases are related to seizures. The diagnosis is usually delayed due to the lack of signs of trauma. Early diagnosis and proper surgical treatment can maximize the final functional results and patient recovery.

Subjective workload measurement of the transition from a conventional operative microscope to a Robotic Digital Microscope. A pilot study.

•Evaluate the subjective workload for transition of an experienced neurosurgeon from a conventional operative microscope /OPMI/ to a Robotic Digital Microscope /RDM/.•Show a single center initial experience of the use an exoscope.•The exoscope improves ergonomics.•Operative exoscope could reduce work-related musculoskeletal disorders.

A rare case of posttraumatic meningitis presenting with acute hydrocephalus.

Posttraumatic meningitis is a severe complication of traumatic brain injury (TBI) that dramatically increases its mortality. Skull-base fractures increase the risk of posttraumatic meningitis. Posttraumatic hydrocephalus was encountered in 0.7 %-29 % of the patients with severe head injury. Posttraumatic hydrocephalus should be differentiated from ventriculomegaly due to brain atrophy. We present a clinical case of a 52-year-old patient after a mild TBI and a linear skull base fracture who developed acute hydrocephalus in the context of a posttraumatic meningitis within the first week after the injury. The occurrence of hydrocephalus in patients with posttraumatic meningitis is not well studied but could lead to rapid deterioration of the patient. It results from injury-induced disturbance of CSF flow either through obstruction or lack of CSF reabsorption. Factors increasing the risk of posttraumatic meningitis are - operative interventions, skull base fractures and CSF leakage. Patients with meningitis usually present with lower GCS score. The lower GCS is a harbinger of worse prognosis. Therefore, aggressive medical treatment is warranted. With this case study we show that meningitis presenting with PTH can develop rapidly over 24 h within the first week post mild head injury with basilar skull fracture. A swift response in providing timely ventricular drainage, together with an appropriate antimicrobial coverage, can greatly reduce any lasting neurological deficits and produce a good clinical outcome.

Surface plasmon excitation on a grating assisted by a cholesteric liquid crystal layer.

While surface plasmon excitation assisted by nematic liquid crystal layers has been comprehensively studied in different aspects, application of cholesteric structures for surface plasmon excitation remains an unexplored area. Moreover, structures including cholesteric layers and metal grating for surface plasmon excitation have never been considered, to the best of our knowledge. We studied theoretically and experimentally such structures focusing on different regimes of propagation of normal modes in the cholesteric liquid crystal layer. The application of such structures for sensing is accordingly discussed.

Raman scattering model of the spin noise.

The mechanism of formation of the polarimetric signal observed in the spin noise spectroscopy (SNS) is analyzed from the viewpoint of the light scattering theory. A rigorous calculation of the polarimetric signal (Faraday rotation or ellipticity) recorded in the SNS is presented in the approximation of single scattering. We show that it is most correctly to consider this noise as a result of scattering of the probe light beam by fluctuating susceptibility of the medium. Fluctuations of the gyrotropic (antisymmetric) part of the susceptibility tensor lead to appearance of the typical for the SNS Faraday rotation noise at the Larmor frequency. At the same time, fluctuations of linear anisotropy of the medium (symmetric part of the susceptibility tensor) give rise to the ellipticity noise of the probe beam spectrally localized at the double Larmor frequency. The results of the theoretical analysis well agree with the experimental data on the ellipticity noise in cesium vapor.

Bench tests of a helium ion source for the neutral particle diagnostic system of the ITER tokamak.

Bench tests of a 15 keV helium ion source, which has been developed for the neutral particle diagnostic system of the International Thermonuclear Experimental Reactor (ITER), are described. Being part of the diagnostic system, the ion source will be used to monitor the intactness of carbon stripping foils as well as to check the detection and dispersion systems of the main diagnostic instruments-neutral particle analyzers (NPAs). The ion source produces a wide 5-cm diameter (FWHM) ion beam at a distance of about 50 cm; the ion beam uniformity at a 2-cm area corresponding to the size of the stripping foil is not worse than 10%. The beam current over the area of the stripping foil can be adjusted in the range of 0.1 pA-1 pA. After initial heating, the temporal stability of the ion beam is better than 10%. Pulse height measurements of registered signals show that 15 keV He+ ions can be reliably registered by the NPA detector system. The obtained results allow us to conclude that the developed ion source can provide a reliable check of the NPA system during the diagnostic performance on the ITER tokamak.

Reconstruction of Fingers Using Skin-Bone Grafts with Microvascular Anastomoses.

The aim of the study was to present a clinical and anatomical rationale for transplantation of skin-bone grafts with microvascular anastomoses for treating terminal and segmental defects of the hand and fingers. MATERIALS AND METHODS: Finger and metacarpal bones were reconstructed in 25 hands of 25 patients by transplanting skin-bone tubular fragments with microvascular anastomoses. Transplants from the second metatarsal bone (n=22) and fibula (n=3) were used. Clinical, radiological, morphological, biomechanical, biophysical, and statistical research methods were used. The developed technology is adjustable to individual vascular anatomy of the foot. The proposed use of non-free skin-fat flaps and skin-bone fragments with microvascular anastomoses has been implemented for reconstructing lost segments. RESULTS: The engraftment of skin-bone fragments was observed in 25 cases. In two cases, partial necrosis of the transplants was detected. Sufficient resistance of the transplanted bone graft to resorption was noted. According to the X-ray evidence, the length of the finger with the metacarpal bone after surgery was 8.44±0.32 cm, in the short term after surgery - 8.10±0.36 cm, and in the long term - 7.87±0.45 cm, indicating mild resorption. We used an individual approach to the transplant selection, which made it possible to obtain generally good long-term results in 3 patients, and satisfactory results - in 22 patients. CONCLUSION: The study showed the feasibility of transplanting skin-bone fragments with microvascular anastomoses for replacing various anatomical defects of the hand and fingers. The proposed modification takes into account the variability of vascular anatomy of the donor region.

Acoustic Radiation Force and Torque on Small Particles as Measures of the Canonical Momentum and Spin Densities.

We examine acoustic radiation force and torque on a small (subwavelength) absorbing isotropic particle immersed in a monochromatic (but generally inhomogeneous) sound-wave field. We show that by introducing the monopole and dipole polarizabilities of the particle, the problem can be treated in a way similar to the well-studied optical forces and torques on dipole Rayleigh particles. We derive simple analytical expressions for the acoustic force (including both the gradient and scattering forces) and torque. Importantly, these expressions reveal intimate relations to the fundamental field properties introduced recently for acoustic fields: the canonical momentum and spin angular momentum densities. We compare our analytical results with previous calculations and exact numerical simulations. We also consider an important example of a particle in an evanescent acoustic wave, which exhibits the mutually orthogonal scattering (radiation-pressure) force, gradient force, and torque from the transverse spin of the field.

Hydrogen-Induced High-Temperature Superconductivity in Two-Dimensional Materials: The Example of Hydrogenated Monolayer MgB_{2}.

Hydrogen-based compounds under ultrahigh pressure, such as the polyhydrides H_{3}S and LaH_{10}, superconduct through the conventional electron-phonon coupling mechanism to attain the record critical temperatures known to date. Here we exploit the intrinsic advantages of hydrogen to strongly enhance phonon-mediated superconductivity in a completely different system, namely, a two-dimensional material with hydrogen adatoms. We find that van Hove singularities in the electronic structure, originating from atomiclike hydrogen states, lead to a strong increase of the electronic density of states at the Fermi level, and thus of the electron-phonon coupling. Additionally, the emergence of high-frequency hydrogen-related phonon modes in this system boosts the electron-phonon coupling further. As a concrete example, we demonstrate the effect of hydrogen adatoms on the superconducting properties of monolayer MgB_{2}, by solving the fully anisotropic Eliashberg equations, in conjunction with a first-principles description of the electronic and vibrational states, and their coupling. We show that hydrogenation leads to a high critical temperature of 67 K, which can be boosted to over 100 K by biaxial tensile strain.

Quantitative determination of pancreas size using anatomical landmarks and its clinical relevance: A systematic literature review.

There have been many reports of altered pancreas size in diseases of the endocrine and exocrine pancreas, but few attempts to quantify such changes. The aim of this study was to conduct a systematic literature review, documenting the methodology, and quantitative data in studies reporting on pancreas size. Three electronic databases (Embase, Scopus, and MEDLINE) were searched by two reviewers independently. Studies of humans were included if they compared pancreas size (reported as pancreas diameters, areas, and/or lengths) between diseased populations and controls. A total of 28 studies with 3,810 individuals were included. Among these, 22 measured pancreas diameters, seven measured pancreas areas, and one measured pancreas lengths. The most common landmark for the head of the pancreas was the confluence of the superior mesenteric and splenic veins (three out of nine studies, 33.3%); for the body it was the superior mesenteric artery (seven out of nine, 77.8%); for the tail it was the internal border of the left kidney (two out of six, 33.3%). Pancreas diameters and areas tended to be smaller in diabetes mellitus, the extent of reduction being greater in individuals with type 1 than type 2 diabetes. Pancreas diameters tended to be greater in acute pancreatitis and pancreatic cancer but not in chronic pancreatitis. Pancreas diameters are a clinically relevant measure for diseases of the endocrine and exocrine pancreas. Consensus guidelines need to be developed to standardize their measurements. Clin. Anat. 31:913-926, 2018. © 2018 Wiley Periodicals, Inc.

Plasmonic and silicon spherical nanoparticle antireflective coatings.

Over the last decade, plasmonic antireflecting nanostructures have been extensively studied to be utilized in various optical and optoelectronic systems such as lenses, solar cells, photodetectors, and others. The growing interest to all-dielectric photonics as an alternative optical technology along with plasmonics motivates us to compare antireflective properties of plasmonic and all-dielectric nanoparticle coatings based on silver and crystalline silicon respectively. Our simulation results for spherical nanoparticles array on top of amorphous silicon show that both silicon and silver coatings demonstrate strong antireflective properties in the visible spectral range. For the first time, we show that zero reflectance from the structure with silicon coatings originates from the destructive interference of electric- and magnetic-dipole responses of nanoparticle array with the wave reflected from the substrate, and we refer to this reflection suppression as substrate-mediated Kerker effect. We theoretically compare the silicon and silver coating effectiveness for the thin-film photovoltaic applications. Silver nanoparticles can be more efficient, enabling up to 30% increase of the overall absorbance in semiconductor layer. Nevertheless, silicon coatings allow up to 64% absorbance increase in the narrow band spectral range because of the substrate-mediated Kerker effect, and band position can be effectively tuned by varying the nanoparticles sizes.

Real-space collapse of a polariton condensate.

Microcavity polaritons are two-dimensional bosonic fluids with strong nonlinearities, composed of coupled photonic and electronic excitations. In their condensed form, they display quantum hydrodynamic features similar to atomic Bose-Einstein condensates, such as long-range coherence, superfluidity and quantized vorticity. Here we report the unique phenomenology that is observed when a pulse of light impacts the polariton vacuum: the fluid which is suddenly created does not splash but instead coheres into a very bright spot. The real-space collapse into a sharp peak is at odd with the repulsive interactions of polaritons and their positive mass, suggesting that an unconventional mechanism is at play. Our modelling devises a possible explanation in the self-trapping due to a local heating of the crystal lattice, that can be described as a collective polaron formed by a polariton condensate. These observations hint at the polariton fluid dynamics in conditions of extreme intensities and ultrafast times.

Classifying the severity of acute pancreatitis: towards a way forward.

BACKGROUND: The recent development of two different severity classifications for acute pancreatitis has appropriately raised questions about which should be used. The aim of this paper is to review the two new severity classifications, outline their differences, review validation studies, and identify gaps in knowledge to suggest a way forward. METHODS: A literature review was performed to identify the purposes and differences between the classifications. Validation studies and those comparing the two different classifications were also reviewed. RESULTS: The Revised Atlanta Classification (RAC) and the Determinants Based Classification (DBC) both rely on assessment of local and systemic factors. The differences between the classifications provides opportunities for further research to improve the accuracy and utility of severity classification. This includes understanding how best to tailor severity classification to setting (e.g. secondary or tertiary hospital) and purpose (e.g. clinical management or research). A key difference is that the RAC does not consider infected pancreatic necrosis an indicator of severe disease. There is also the need to develop methods for the accurate non-invasive diagnosis of infected necrosis and evaluation of the characteristics of organ dysfunction in relation to severity and outcome. CONCLUSION: Further improvement in severity classification is possible and research priorities have been identified. For now, the decision as to which classification to use should be on the basis of setting, validity, accuracy, and ease of use.

Meta-analysis of gut barrier dysfunction in patients with acute pancreatitis.

BACKGROUND: The gut is implicated in the pathogenesis of acute pancreatitis but there is discrepancy between individual studies regarding the prevalence of gut barrier dysfunction in patients with acute pancreatitis. The aim of this study was to determine the prevalence of gut barrier dysfunction in acute pancreatitis, the effect of different co-variables, and changes in gut barrier function associated with the use of various therapeutic modalities. METHODS: A literature search was performed using PRISMA and MOOSE guidelines. Summary estimates were presented as pooled prevalence of gut barrier dysfunction and the associated 95 per cent c.i. RESULTS: A total of 44 prospective clinical studies were included in the systematic review, of which 18 studies were subjected to meta-analysis. The pooled prevalence of gut barrier dysfunction was 59 (95 per cent c.i. 48 to 70) per cent; the prevalence was not significantly affected by disease severity, timing of assessment after hospital admission or type of test used, but showed a statistically significant association with age. Overall, nine of 13 randomized clinical trials reported a significant improvement in gut barrier function following intervention compared with the control group, but only three of six studies that used standard enteral nutrition reported a statistically significant improvement in gut barrier function after intervention. CONCLUSION: Gut barrier dysfunction is present in three of five patients with acute pancreatitis, and the prevalence is affected by patient age but not by disease severity. Clinical studies are needed to evaluate the effect of enteral nutrition on gut function in acute pancreatitis.

[Acute pain syndrome and levels of peripheral blood saturation after various thoracic surgical approaches].

The traumatic effect of surgical approaches was determined by the intensity and duration of pain syndrome and by the degree of lung ventilation disturbances after thoracic surgery. An acute pain syndrome was considered by visual analog pain scale and a blood saturation level for the first 5 days after operation. There were 3 groups, each group consisted of 31 patients. All patients were after thoracotomies, thoracoscopies, rethoracoscopies. Maximal intensity of pain appeared to be after thoracotomies and its degree has been reducing since the first till fifth day (from 8.1 +/- 1.7 to 4.2 +/- 0.9 points). The pain syndrome was reliably less after thoracoscopy (from 5.9 +/- 1.6 to 3.5 +/- 1.4 points). Minimal pain was noted after revideothoracoscopies with the dynamics from 4.0 +/- 2.4 to 2.7 +/- 1.2 points. The rate of blood saturation was more reduced after thoracotomy for the first two days till 92.9 +/- 4.6% and the saturation level became equal on the third day in all groups. Obtained data objectively confirmed the considerably less injury in the case of endoscopic thoracic approaches in comparison with open intervention.

Diaphragm remodeling and compensatory respiratory mechanics in a canine model of Duchenne muscular dystrophy.

Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.

[International multidisciplinary classification of acute pancreatitis severity: the 2013 Spanish edition]. / Clasificación Internacional y Multidisciplinaria de la Pancreatitis Aguda: Edición Española 2013.

OBJECTIVE: To develop a new classification of acute pancreatitis severity on the basis of a sound conceptual framework, comprehensive review of the published evidence, and worldwide consultation. BACKGROUNDS: The Atlanta definitions of acute pancreatitis severity are ingrained in the lexicon of specialist in pancreatic diseases, but are suboptimal because these definitions are based on the empiric description of events not associated with severity. METHODS: A personal invitation to contribute to the development of a new classification of acute pancreatitis severity was sent to all surgeons, gastroenterologists, internists, intensivists and radiologists currently active in the field of clinical acute pancreatitis. The invitation was not limited to members of certain associations or residents of certain countries. A global web-based survey was conducted, and a dedicated international symposium was organized to bring contributors from different disciplines together and discuss the concept and definitions. RESULTS: The new classification of severity is based on the actual local and systemic determinants of severity, rather than on the description of events that are non-causally associated with severity. The local determinant relates to whether there is (peri) pancreatic necrosis or not, and if present, whether it is sterile or infected. The systemic determinant relates to whether there is organ failure or not, and if present, whether it is transient or persistent. The presence of one determinant can modify the effect of another, whereby the presence of both infected (peri) pancreatic necrosis and persistent organ failure has a greater impact upon severity than either determinant alone. The derivation of a classification based on the above principles results in four categories of severity: mild, moderate, severe, and critical. CONCLUSIONS: This classification is the result of a consultative process among specialists in pancreatic diseases from 49 countries spanning North America, South America, Europe, Asia, Oceania and Africa. It provides a set of concise up to date definitions of all the main entities pertinent to classifying the severity of acute pancreatitis in clinical practice and research. This ensures that the determinant-based classification can be used in a uniform manner throughout the world.