Pediatric Sinogenic Subdural Empyema: Case Report and Operative Technique

Intracranial complications of sinusitis in the pediatric age are rare but potentially life threatening. They usually occur with nonspecific symptoms such as headache, fever, nausea and vomiting rather than a classic neurological presentation, but they may evolve in few hours, leading to significant morbidity with permanent brain damage and sometimes to death. For this reason, early diagnosis and prompt treatment are essential. Our case demonstrates a sinogenic subdural empyema in an immunocompetent young boy who reached our Emergency Department due to a continuous right-sided headache, unresponsive to pain relievers. The clinical history and the diagnostic process are described: at first, laboratory exams, neurologic and otolaryngological assessment were performed, together with a cranial CT scan showing an inflammatory involvement of the right frontal, ethmoidal and maxillary sinuses. Intravenous antibiotic therapy was initiated. After a few hours the patient showed a sudden worsening of his clinical conditions: he was drowsy with left lower extremity hyposthenia and ipsilateral deep tendon reflexes absence. Considering the patient’s aggravated clinical presentation an emergent MRI with contrast enhancement was conducted, showing left midline shift, a widening of the liquor space on the right frontal and parietal convexity and noticeable meningeal enhancement after contrast injection. After a Neurosurgical and ENT evaluation the patient was taken to the operating room for a combined craniotomy and trans-nasal endoscopic drainage of the empyema. We present the surgical procedure with a pictorial step-by-step description. After the surgical procedure the patient’s condition gradually improved. He regained full neurological function, was accompanied by a rehabilitation team on recovering full force on the left extremities. At discharge the patient had no apparent neurological deficits. Subdural empyema is a rare but severe complication of pediatric sinusitis. Early diagnosis with combined medical and surgical therapies play a key role to reduce morbidity and mortality

Covid-19 and ENT practice: Our experience: ENT outpatient department, ward and operating room management during the SARS-CoV-2 pandemic

Coronavirus COVID-19 SARS-CoV-2 ENT Otolaryngolog

Structural relaxations in electronically excited poly(para-phenylene)

Structural relaxations in electronically excited poly(para-phenylene) are studied using many-body perturbation theory and density-functional-theory methods. A sophisticated description of the electron-hole interaction is required to describe the energies of the excitonic states, but we show that the structural relaxations associated with exciton formation can be obtained quite accurately within a constrained density-functional-theory approach. We find that the structural relaxations in the low-energy excitonic states extend over about 8 monomers, leading to an energy reduction of 0.22 eV and a Stokes shift of 0.40 eV.Comment: 4 pages, 3 figure

Structural, electronic, and dynamical properties of amorphous gallium arsenide: a comparison between two topological models

We present a detailed study of the effect of local chemical ordering on the structural, electronic, and dynamical properties of amorphous gallium arsenide. Using the recently-proposed ``activation-relaxation technique'' and empirical potentials, we have constructed two 216-atom tetrahedral continuous random networks with different topological properties, which were further relaxed using tight-binding molecular dynamics. The first network corresponds to the traditional, amorphous, Polk-type, network, randomly decorated with Ga and As atoms. The second is an amorphous structure with a minimum of wrong (homopolar) bonds, and therefore a minimum of odd-membered atomic rings, and thus corresponds to the Connell-Temkin model. By comparing the structural, electronic, and dynamical properties of these two models, we show that the Connell-Temkin network is energetically favored over Polk, but that most properties are little affected by the differences in topology. We conclude that most indirect experimental evidence for the presence (or absence) of wrong bonds is much weaker than previously believed and that only direct structural measurements, i.e., of such quantities as partial radial distribution functions, can provide quantitative information on these defects in a-GaAs.Comment: 10 pages, 7 ps figures with eps

A simple model of radiative emission in M87

We present a simple physical model of the central source emission in the M87 galaxy. It is well known that the observed X-ray luminosity from this galactic nucleus is much lower than the predicted one, if a standard radiative efficiency is assumed. Up to now the main model invoked to explain such a luminosity is the ADAF (Advection-Dominated-Accretion-Flow) model. Our approach supposes only a simple axis-symmetric adiabatic accretion with a low angular momentum together with the bremsstrahlung emission process in the accreting gas. With no other special hypothesis on the dynamics of the system, this model agrees well enough with the luminosity value measured by Chandra.Comment: 11 pages, 6 figures, accepted for publication in The Astrophysical Journa

Path Tracing vs. Volume Rendering Technique in Post-Surgical Assessment of Bone Flap in Oncologic Head and Neck Reconstructive Surgery: A Preliminary Study

This study aims to compare a relatively novel three-dimensional rendering called Path Tracing (PT) to the Volume Rendering technique (VR) in the post-surgical assessment of head and neck oncologic surgery followed by bone flap reconstruction. This retrospective study included 39 oncologic patients who underwent head and neck surgery with free bone flap reconstructions. All exams were acquired using a 64 Multi-Detector CT (MDCT). PT and VR images were created on a dedicated workstation. Five readers, with different expertise in bone flap reconstructive surgery, independently reviewed the images (two radiologists, one head and neck surgeon and two otorhinolaryngologists, respectively). Every observer evaluated the images according to a 5-point Likert scale. The parameters assessed were image quality, anatomical accuracy, bone flap evaluation, and metal artefact. Mean and median values for all the parameters across the observer were calculated. The scores of both reconstruction methods were compared using a Wilcoxon matched-pairs signed rank test. Inter-reader agreement was calculated using Spearman’s rank correlation coefficient. PT was considered significantly superior to VR 3D reconstructions by all readers (p < 0.05). Inter-reader agreement was moderate to strong across four out of five readers. The agreement was stronger with PT images compared to VR images. In conclusion, PT reconstructions are significantly better than VR ones. Although they did not modify patient outcomes, they may improve the post-surgical evaluation of bone-free flap reconstructions following major head and neck surgery

Tracheostomy in the COVID-19 pandemic

Purpose: The role of tracheostomy in COVID-19-related ARDS is unknown. Nowadays, there is no clear indication regarding the timing of tracheostomy in these patients. Methods: We describe our synergic experience between ENT and ICU Departments at University Hospital of Modena underlining some controversial aspects that would be worth discussing tracheostomies in these patients. During the last 2 weeks, we performed 28 tracheostomies on patients with ARDS due to COVID-19 infection who were treated with IMV. Results: No differences between percutaneous and surgical tracheostomy in terms of timing and no case of team virus infection. Conclusion: In our experience, tracheostomy should be performed only in selected patients within 7- and 14-day orotracheal intubation

Exoskeletons for workers: A case series study in an enclosures production line

This case-series study aims to investigate the effects of a passive shoulder support exoskeleton on experienced workers during their regular work shifts in an enclosures production site. Experimental activities included three sessions, two of which were conducted in-field (namely, at two workstations of the painting line, where panels were mounted and dismounted from the line; each session involved three participants), and one session was carried out in a realistic simulated environment (namely, the workstations were recreated in a laboratory; this session involved four participants). The effect of the exoskeleton was evaluated through electromyographic activity and perceived effort. After in-field sessions, device usability and user acceptance were also assessed. Data were reported individually for each participant. Results showed that the use of the exoskeleton reduced the total shoulder muscular activity compared to normal working conditions, in all subjects and experimental sessions. Similarly, the use of the exoskeleton resulted in reductions of the perceived effort in the shoulder, arm, and lower back. Overall, participants indicated high usability and acceptance of the device. This case series invites larger validation studies, also in diverse operational contexts

Why Canonical Disks Cannot Produce Advection Dominated Flows

Using simple arguments we show that the canonical thin keplerian accretion disks cannot smoothly match any plain advection dominated flow (ADAF) model. By 'plain' ADAF model we mean the ones with zero cooling. The existence of sonic points in exact solutions is critical and imposes constraints that cannot be surpassed adopting 'reasonable' physical conditions at the hypothetical match point. Only the occurrence of new critical physical phenomena may produce a transition. We propose that exact advection models are a class of solutions which don't necessarily involve the standard thin cool disks and suggest a different scenario in which good ADAF solutions could eventually occur.Comment: 12 pages, 2 figures, Accepted for publication in Ap.J. Letter