On the Convexity of a Fragment of Pure Set Theory with Applications within a Nelson-Oppen Framework

In Proceedings GandALF 2021, arXiv:2109.0779

Impasse in the management of recurrent basal cell carcinoma of the skull with sagittal sinus erosion

Basal cell carcinoma (BCC) is a non melanocytic skin cancer that arises from basal cells, affecting commonly fair-skinned human beings. Although the tumor is well known for local recurrences, extension into the intracranial space is reported. A case of a giant BCC of the scalp invading the middle and posterior third of the superior sagittal sinus (SSS) is reported. A 70-year-old male with a basal cell carcinoma history presented with a massive bleeding from the SSS invaded by the tumor. Since the patient refused surgery the bleeding was managed through direct compression by applying a thrombin-based hemostatic agents and sterile dressings. This procedure was performed daily in order to stimulate the spontaneous thrombosis of the dural sinus and development of collateral circle. BCC invading the SSS is rarely reported. A technical description of this case is provided. This case underscores the importance of early and appropriate treatment for high risk BCC, and whenever surgical procedure is not suitable appropriate conservative treatment may be efficacious

Complex reconstructive surgery following removal of extra-intracranial meningiomas, including the use of autologous fibrin glue and a pedicled muscle flap

Background: Skull reconstructive surgery is critical to prevent cerebrospinal fluid (CSF) fistulas and infections, and to ensure good aesthetic results in meningiomas surgery. Methods: A 65-year-old woman was surgically treated for a bilateral parasagittal meningioma with complete superior sagittal sinus (SSS) involvement, and an intra-extracranial extension, determining a significant cranial defect at the vertex. A Simpson I resection was achieved. Postoperatively a considerable and not conservatively repairable CSF leak was detected. Surgical revision of the wound with repair of the fistula and complex reconstructive operation was performed including a combination of techniques and devices such as autologous fibrin glue and reparation of the extracranial planes by an autologous vascularized vastus lateralis pedicled muscle flap. Results: No postoperative complications, infections or new neurological deficits were detected, and the CSF leak definitively ceased after surgery; the aesthetic results were satisfactory. Conclusions: Reparation of CSF fistulas that arise after meningioma surgery can require a complex reconstructive surgery of the superficial layers; when cranioplasty is not feasible or indicated, a meticulous reconstruction of the extracranial soft tissues is possible also by using vascularized autologous distal muscular tissue, with close interdisciplinary cooperation

Unusual recurrence of trigeminal neuralgia after microvascular decompression by muscle interposal

Background: Patients with trigeminal neuralgia (TN) and persistent or recurrent facial pain after microvascular decompression (MVD) typically undergo less invasive procedures in the hope of providing pain relief. However, re-operation should be considered in selected patients. Case Report: A 48-year-old woman presented with recurrent trigeminal neuralgia (TN) 3 years following microvascular decompression (MVD). The patient underwent brain magnetic resonance angiography (MRA), which did not reveal neurovascular compression; therefore surgical re-exploration was carried out. During the operation, the fifth cranial nerve was seen without impingement from any blood vessels; however, a very firm tissue was observed and identified as the muscle fragment from the previous MVD procedure. The fifth cranial nerve was carefully separated from the muscle. Thereafter, the right SCA was dissected out from the muscle and suspended by a periosteum tape sutured to the nearby dura. Conclusions: Our findings, along with similar cases reported in the literature, support the development of new inert materials and alternative surgical strategies that can limit TN recurrence

Shear Testing of Topologically Optimised Web Cover Plates in Splice Connections – Experiment Design and Results

Testing shear-resisting plates in steel connections is one of the most challenging laboratory undertakings in steel construction, as the most common experimental layout design includes simulating the connection with its adjoining members. This significant hindrance gained particular magnitude as the need to test prototypes of topologically optimised shear cover plates became more pressing. Indeed, new code-compliant topology optimisation approaches for steel construction have recently been offered, and physically non-linear analyses have been demonstrated to be vital for assessing these elements. Hence, a rapid and reliable experimental process has become a fundamental necessity. To answer this need, a novel layout is herein proposed, in which topologically optimised and previously numerically examined bolted shear plates of a well-known steel joint were tested. The results allowed for the definition of the material trilinear model for use in subsequent numerical analysis, as well as the validation of the numerical simulation results. The discrepancy between the previously mathematically anticipated and empirically determined ultimate resistance did not exceed 1.7%.info:eu-repo/semantics/publishedVersio

Fiber-reinforced lightweight foamed concrete panels suitable for 3D printing applications

This contribution presents a set of experimental results on fiber-reinforced innovative lightweight panels (FRIL-panels) having thickness of 12mm. These panels are prepared with a peculiar foamed concrete that has a high viscosity and cohesion in the fresh state, which makes it particularly suitable for 3D printing applications. The FRIL-panels can be used for internal partitions, external infills, and suspended ceilings of buildings as more effective solutions than conventional plasterboard ones, with better thermal insulation and acoustic absorption properties due to the internal air-void microstructure. The aim of this work is to investigate the out-of-plane resistance of FRIL-panels, prepared with a density of 800kg/m3, under displacement-controlled three-point bending tests. In view of potential use in the precast industry, the FRIL-panels were placed into an accelerated concrete curing tank so as to speed up the overall production process. Modulus of rupture, ultimate deflection and collapse mode of FRIL-panels are critically analysed and discussed

White cord syndrome after non-contiguous double-level anterior cervical decompression and fusion (ACDF): A "no reflow phenomenon"?

Abstract Study design Case report and review of literature. Objective To report a rare complication of anterior cervical decompression and fusion (ACDF) in a patient with severe cervical cord compression and review of relevant literature. Introduction The white cord syndrome is a very rare condition characterized by an ischemic-edematous lesion of the spinal cord following a surgical procedure, lacking intra o perioperative surgical or anesthesiological complications. Case report A 64-years old male affected by a severe cervical stenosis at multiple levels, with voluminous C3–C4 and C5–C6 disc herniations associated to T2-hyperintense myelomalacic area at C3–C4 level was admitted to our Unit of Neurosurgery in July 2015. A double-level anterior cervical decompression and fusion (ACDF) procedure was performed without intraoperative complications and, in the immediate post-operative period, the patient developed a severe motor weakness to four limbs. The post-operative cervical spine MRI revealed an extension of the hyperintensity on the C5–C6 level. In the immediate post-operative course high doses of dexamethasone were administered, in order to treat the secondary spinal damage. The patient was, after few days, transferred to a Rehabilitation Unit where a partial improvement of the motor weakness was gradually observed. We report the second case of this complication in Literature to support the theory of a possible reperfusion injury after a double ACDF. We speculate an ethiologic mechanism similar to a long-term no-reflow phenomenon, likely during the post-ischemic period in myocardial or cerebral infarction. Conclusions Despite the pathophysiology of non-reflow phenomenon is not widely known, we suspect that an improper blood flow after the double-level discectomy could have led to the changes in medullar hemodynamics

Autologous fibrin sealant (Vivostat®) in the neurosurgical practice: Part I: Intracranial surgical procedure

Background: Hemorrhages, cerebrospinal fluid (CSF) fistula and infections are the most challenging postoperative complications in Neurosurgery. In this study, we report our preliminary results using a fully autologous fibrin sealant agent, the Vivostat® system, in achieving hemostasis and CSF leakage repair during cranio-cerebral procedures. Methods: From January 2012 to March 2014, 77 patients were studied prospectively and data were collected and analyzed. Autologous fibrin sealant, taken from patient's blood, was prepared with the Vivostat® system and applied on the resection bed or above the dura mater to achieve hemostasis and dural sealing. The surgical technique, time to bleeding control and associated complications were recorded. Results: A total of 79 neurosurgical procedures have been performed on 77 patients. In the majority of cases (98%) the same autologous fbrin glue provided rapid hemostasis and dural sealing. No patient developed allergic reactions or systemic complications in association with its application. There were no cases of cerebral hematoma, swelling, infection, or epileptic seizures after surgery whether in the immediate or in late period follow-up. Conclusions: In this preliminary study, the easy and direct application of autologous fibrin sealant agent helped in controlling cerebral bleeding and in providing prompt and efficient dural sealing with resolution of CSF leaks. Although the use of autologous fibrin glue seems to be safe, easy, and effective, further investigations are strongly recommended to quantify real advantages and potential limitations

Ostruzione polmonare ed aritmia respiratoria

Il monitoraggio di pazienti tramite segnali fotopletismografici (PhotoPlethysmoGram, PPG) acquisiti sul polso, arteria radiale, piuttosto che sulla punta dell’indice, permette di ottenere un segnale più stabile e con maggiori informazioni, come la gittata cardiaca, la durata della contrazione ventricolare e la chiusura dell’aorta. In questo lavoro è presentata un’attività preliminare per rilevare condizioni come l’ostruzione polmonare e le apnee notturne. Si è indagato l’andamento dell’aritmia respiratoria in relazione ad eventuali difficoltà respiratorie. Per il momento ci si è limitati ad osservare soggetti sani e l’ostruzione è stata simulata facendo respirare i soggetti attraverso una cannuccia

Early high-dosage atorvastatin treatment improved serum immune-inflammatory markers and functional outcome in acute ischemic strokes classified as large artery atherosclerotic stroke: A randomized trial

Statins have beneficial effects on cerebral circulation and brain parenchyma during ischemic stroke and reperfusion. The primary hypothesis of this randomized parallel trial was that treatment with 80 mg/day of atorvastatin administered early at admission after acute atherosclerotic ischemic stroke could reduce serum levels of markers of immune-inflammatory activation of the acute phase and that this immune-inflammatory modulation could have a possible effect on prognosis of ischemic stroke evaluated by some outcome indicators. We enrolled 42 patients with acute ischemic stroke classified as large arteries atherosclerosis stroke (LAAS) randomly assigned in a randomized parallel trial to the following groups: Group A, 22 patients treated with atorvastatin 80mg (once-daily) from admission day until discharge; Group B, 20 patients not treated with atorvastatin 80mg until discharge, and after discharge, treatment with atorvastatin has been started. At 72 hours and at 7 days after acute ischemic stroke, subjects of group A showed significantly lower plasma levels of tumor necrosis factor-a, interleukin (IL)-6, vascular cell adhesion molecule-1, whereas no significant difference with regard to plasma levels of IL-10, E-Selectin, and P-Selectin was observed between the 2 groups. At 72 hours and 7 days after admission, stroke patients treated with atorvastatin 80mg in comparison with stroke subjects not treated with atorvastatin showed a significantly lower mean National Institutes of Health Stroke Scale and modified Rankin scores. Our findings provide the first evidence that atorvastatin acutely administered immediately after an atherosclerotic ischemic stroke exerts a lowering effect on immune-inflammatory activation of the acute phase of stroke and that its early use is associated to a better functional and prognostic profile