42 research outputs found
La chirurgia endoscopica della giunzione cranio-vertebrale
No full textLa chirurgia endoscopica della giunzione cranio-vertebral
Radiological assessment of the sinus tympani: temporal bone HRCT analyses and surgically related findings
No full textTo evaluate the morphology of the sinus tympani (ST) based on computed tomography (CT) scans (axial view), describing the findings in a cohort of 148 patients (296 ears), and classifying the prevalence according to our ST classification. To evaluate the surgical prevalence based on the type of ST. To calculate the sensibility and positive predictive value (PPV) of high-resolution computed tomography (HRCT) scans for ST involvement by cholesteatoma.To evaluate the morphology of the sinus tympani (ST) based on computed tomography (CT) scans (axial view), describing the findings in a cohort of 148 patients (296 ears), and classifying the prevalence according to our ST classification. To evaluate the surgical prevalence based on the type of ST. To calculate the sensibility and positive predictive value (PPV) of high-resolution computed tomography (HRCT) scans for ST involvement by cholesteatoma. Methods: Retrospective review of the radiologic database and surgical reports. Results: In total, 98/296 (33.1 %) middle ears presented a radiologic morphology Type A; 185/296 (62.5 %) middle ears presented a radiologic morphology Type B; 13/296 (4.4 %) middle ears presented a radiologic morphology Type C; HRCT showed a sensibility of 91 %, specificity of 65 %, PPV of 68 % and negative predictive value (NPV) of 90 %. Conclusions: ST shape and depth can influence surgical preference in cholesteatoma surgery. In the case of a shallower ST, an exclusive endoscopic exploration is chosen; whereas in the case of a deeper ST, a retrofacial approach is usually preferred. HRCT scans demonstrated high sensibility and NPV for ST involvement by cholesteatoma
Preface - E-MRS Fall Symposium I: Solutions for Critical Raw Materials Under Extreme Conditions
No full textWear and Fretting Behavior of Cold Sprayed IN625 Superalloy
No full textThe wear and fretting behaviour of IN625 cold spray coatings was analysed and the results are presented. The cold spray conditions were selected in order to obtain coatings with minimum porosity and maximum particles splat. This leads to compact and hard deposited material able to resist wear damaging and to dissipate energy during fretting. The coating’s strength was evaluated through nanoindentation that revealed an increased hardness from the surface toward the substrate. This different hardening behaviour from the coating surface toward the substrate leads to increased resistance to fretting and wear as the maximum stresses increase. This was revealed by scratch tests performed at linearly increasing loads that allowed identifying of the damage mechanisms acting on the coating as the triaxial stresses increase. The hardening behaviour of the coating also influenced the fretting behaviour revealed by the weight loss experienced by varying the fretting maximum load
Fatigue Bending Behavior of Cold-Sprayed Nickel-Based Superalloy Coatings
No full textCold-sprayed Ni-based superalloy coatings offer new possibilities for manufacturing and repairing damaged components, such as gas turbine blades or other parts of aircraft engines. This development shines a new light on the conventional additive manufacturing technologies and significantly broadens application fields of cold spray. The idea is that cold spray can contribute to improving the fatigue properties of manufacturing and repaired components. This study deals with the analysis of the microstructural and mechanical properties of IN625 cold-sprayed coatings on V-notched carbon steel substrate. Process conditions of 1000 °C and 50 bar were employed to produce coatings in V-notched (60° and 90°) samples in order to evaluate the fatigue crack behavior of the sprayed material. Bending tests were carried out in order to evaluate the crack propagation in the coatings during cyclic loading. The K factor was quantified for the two different notch geometries. After fatigue tests, the cracking mechanisms were observed through SEM. Optical microscopy, nanoindentation as a function of coating/substrate distance and corrosion tests were performed. Porosity measurements through image analyses were done to characterize the coatings’ quality. The results achieved demonstrate that cold spray deposition and repair can contribute to resistance and to the increase in the global fatigue life of cracked structures
Head and Neck Cancer During Covid-19 Pandemic: Was there a Diagnostic Delay?
No full textThe aim of the present study is to investigate a possible delay in diagnosis and therapy administration for Head and Neck oncological patients, during the Sars-Cov2 pandemic and to compare the median tumor stage (MTS) at presentation. This is a retrospective review on patients who presented at the University Hospital of Modena with a newly diagnosis of Head and Neck cancer (HNC), comparing the first pandemic period (from March 1st, to October 15th 2020) to the same period of 2019. The time in days from the diagnostic suspicion to the beginning of the treatment, hereafter referred to as delay in treatment initiation (DTI), and the tumor stage were calculated for all the enrolled patients. Mean percentage of reduction of the clinical and surgical activities was − 25.8% (range: − 66–1.5%), with higher percentages in phase 1 for all the analyzed activities. 125 HNC patients were enrolled in the analysis as the study group, compared with a cohort of 140 patients from the previous year. The MTS was III for both groups, however a significant statistical difference was determined in the stage comparison, p = 0.023. When DTI was analyzed no statistically significant differences were appreciated. A more advanced stage at presentation was demonstrated at our institution for HNC patients during the first phase of the Covid-19 pandemic in 2020. However, a statistically significant delay in time between diagnosis and therapy administration was not assessed, thus confirming the maintenance of a high level of care even in the COVID-19 era
Modal analysis of novel coronavirus (SARS COV-2) using finite element methodology
No full textMany new engineering and scientific innovations have been proposed to date to passivate the novel coronavirus (SARS CoV-2), with the aim of curing the related disease that is now recognised as COVID-19. Currently, vaccine development remains the most reliable solution available. Efforts to provide solutions as alternatives to vaccinations are growing and include established control of behaviours such as self-isolation, social distancing, employing facial masks and use of antimicrobial surfaces. The work here proposes a novel engineering method employing the concept of resonant frequencies to denature SARS CoV-2. Specifically, “modal analysis” is used to computationally analyse the Eigenvalues and Eigenvectors i.e. frequencies and mode shapes to denature COVID-19. An average virion dimension of 63 nm with spike proteins number 6, 7 and 8 were examined, which revealed a natural frequency of a single virus in the range of 88–125 MHz. The information derived about the natural frequency of the virus through this study will open newer ways to exploit medical solutions to combat future pandemics
SARS-CoV-2 tracheitis in laryngectomised patients: A consecutive case-series study
No full textKey points
SARS-CoV-2 is a possible cause of acute severe tracheitis in laryngectomees.
In our series, the clinical picture was characterized by a haemorrhagic tracheitis with a
slow resolution pattern.
We observed a histological pattern of erosive inflammation of the respiratory
epithelium.
Planned tracheo-bronchoscopy and tracheal toilettes are recommended to prevent
critical obstruction of the airway, which can be fatal in patients with associated
impairment of lung function caused by SARS-CoV-2 infection.
The present cases highlight the need for close interdisciplinary working and
communication in the management of airway complications of COVID-19 infection
Radiological assessment of the sinus tympani: temporal bone HRCT analyses and surgically related findings
No full textPurpose: To evaluate the morphology of the sinus tympani (ST) based on computed tomography (CT) scans (axial view), describing the findings in a cohort of 148 patients (296 ears), and classifying the prevalence according to our ST classification. To evaluate the surgical prevalence based on the type of ST. To calculate the sensibility and positive predictive value (PPV) of high-resolution computed tomography (HRCT) scans for ST involvement by cholesteatoma. Methods: Retrospective review of the radiologic database and surgical reports. Results: In total, 98/296 (33.1 %) middle ears presented a radiologic morphology Type A; 185/296 (62.5 %) middle ears presented a radiologic morphology Type B; 13/296 (4.4 %) middle ears presented a radiologic morphology Type C; HRCT showed a sensibility of 91 %, specificity of 65 %, PPV of 68 % and negative predictive value (NPV) of 90 %. Conclusions: ST shape and depth can influence surgical preference in cholesteatoma surgery. In the case of a shallower ST, an exclusive endoscopic exploration is chosen; whereas in the case of a deeper ST, a retrofacial approach is usually preferred. HRCT scans demonstrated high sensibility and NPV for ST involvement by cholesteatoma
Reply to “Indications and timing for tracheostomy in patients with SARS CoV2‐related” by Ferri et al
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