A giant trigeminal schwannoma of the infratemporal fossa removed by transmandibular approach and coronoidectomy

The whole spectrum of infratemporal fossa (IF) tumors comprises both intra- and extracranial tumors. Schwannomas are benign nerve tumors arising from the Schwann cells. Approximately 25%-45% of schwannomas occur in the head and neck region. The lesions commonly arise from the roots of cranial and cervical nerves in the parapharyngeal space, with the majority originating from the vagus nerve. Trigeminal schwannomas account for about 0.2% of all intracranial tumors, and 0.8% and 8% of intracranial schwannomas. Trigeminal schwannomas are commonly located in the intracranium. Exclusive extracranial trigeminal schwannoma are exceptional lesions that may also involve the maxillary sinus, the orbit, and the parapharyngeal space. Schwannomas of the head and neck can originate from any section of the fifth cranial nerve, from the root to the distal extracranial branches, but the majority develops at the Gasserian ganglion, usually growing in the middle cranium. Schwannomas arising primarily within the IF, without intracranial extension, are extremely rare. Many approaches were described for extracranial trigeminal schwannomas originating from the skull base, such as transmaxillary approach, or Le Fort I type I osteotomy, or facial translocation approach, or infratemporal approach, or transmandibular transcervical approaches. We present a case of voluminous extracranial schwannoma, arising from the extradural divisions of the trigeminal nerve, extending in the IF and parapharyngeal space, treated via a transmandibular approach. The literature regarding extracranial schwannomas of the IF and parapharyngeal space, and their approaches are reviewed

A Rare Cause for Cervical Pain: Eagle's Syndrome

Patients with pharyngodynia and neck pain symptoms can lead to an extensive differential diagnosis. Eagle's syndrome must be taken in account. Eagle defined “stylalgia” as an autonomous entity related to abnormal length of the styloid process or to mineralization of the stylohyoid ligament complex. The stylohyoid complex derives from Reichert's cartilage of the second branchial arch. The styloyd process is an elongated conical projection of the temporal bone that lies anteriorly to the mastoid process. The incidence of Eagle's syndrome varies among population. Usually asymptomatic, it occurs in adult patients. It is characterized by pharyngodynia localized in the tonsillar fossa and sometimes accompanied by disphagia, odynophagia, foreign body sensation, and temporary voice changes. In some cases, the stylohyoid apparatus compresses the internal and/or the external carotid arteries and their perivascular sympathetic fibers, resulting in a persistent pain irradiating in the carotid territory. The pathogenesis of the syndrome is still under discussion

Stability of splay states in globally coupled rotators

The stability of dynamical states characterized by a uniform firing rate ({\it splay states}) is analyzed in a network of $N$ globally pulse-coupled rotators (neurons) subject to a generic velocity field. In particular, we analyse short-wavelength modes that were known to be marginally stable in the infinite $N$ limit and show that the corresponding Floquet exponent scale as $1/N^2$. Moreover, we find that the sign, and thereby the stability, of this spectral component is determined by the sign of the average derivative of the velocity field. For leaky-integrate-and-fire neurons, an analytic expression for the whole spectrum is obtained. In the intermediate case of continuous velocity fields, the Floquet exponents scale faster than $1/N^2$ (namely, as $1/N^4$) and we even find strictly neutral directions in a wider class than the sinusoidal velocity fields considered by Watanabe and Strogatz in {\it Physica D 74 (1994) 197-253}.Comment: 7.7 pages - 16 Figures - Submitted to Physical Review

Stability criteria for splay states in networks of "generalized" neuronal models

Splay states represent collective modes emerging in networks of fully coupled oscillators, they have been observed in Josephson junction arrays, laser systems, pulse-coupled neuronal networks [1]. Recently, their stability analysis has been redone by reducing a model of globally coupled differential equations to suitable event-driven maps which relate the internal configuration at two consecutive spike-emissions. [2]. This analysis has revealed that the mean-field analysis reported in [1] has neglected a part of the Floquet spectrum associated to "short wavelengths (SW) modes". The aim of the present analysis is to show that the SW part of the Floquet spectrum can be crucial for the stability of the splay states in fully pulse-coupled networks when generic neuronal models, different from the usual leaky integrate-and-fire (LIF) model are considered. For the LIF case corresponding to a force field F(x) = a-x, the SW Floquet spectrum is fully degenerate and marginally stable in the limit of infinite network, however for finite number of neurons N, the splay state is stable and the maximal exponent approach zero as 1/N2. We have performed the stability analysis for a generic (non)-linear periodic force field, by rewriting the dynamics of the network as approximated event-driven maps (correct up to fourth order in the mean interspike interval, that is proportional to 1/N). For continuous force fields, the splay state appears to be neutrally stable along most of the directions (apart a finite number). These findings generalize to a larger class of systems a previous result by Watanabe and Strogatz [3]. While for discontinuous force fields the stability or instability of the splay state is simply determined by the sign of the force field difference taken at the extrema of the definition interval

The authors' reply

We appreciate Dr West's comments on our paper1; he has given us the opportunity to clarify some points that seem unresolved

Multivessel revascularisation in ST-elevation myocardial infarction: Too early to change the guidelines

Multivessel revascularisation in ST-elevation myocardial infarction: too early to change the guideline

Endoscopically assisted procedure for removal of a foreign body from the maxillary sinus and contemporary endodontic surgical treatment of the tooth

There have been reports on the migration of teeth or implants into the maxillary sinus. We know of only one report on the migration of a gutta-percha point that had been used to fill a root canal into the ethmoid sinus. We report such a case treated with an endoscopically assisted procedure for removal of the foreign body and contemporary endodontic surgical treatment of the tooth

Application of a new photocatalytic nanomaterial obtained by Pulse Laser Ablation for Polychrome Paintings Conservation: a feasibility study

This works aims to present a preliminary study about the application on painting of TiO2 nanoparticles for self-cleaning and protective purposes. We firstly assessed the photocatalytic activity of the TiO2 nanoparticles, obtained by Pulsed Laser Ablation, by the discoloration of dye. After, the colloidal dispersion is applied to painting samples prepared in laboratory, according to old recipes and using the most-used historical binders and pigments, in order to verify the cleaning efficiency by discoloration of the chromatic markers. The spectrophotometric analysis is performed studying the Spectral Reflectance Factor trend and the color coordinates

Nonlinearly driven transverse synchronization in coupled chaotic systems

Synchronization transitions are investigated in coupled chaotic maps. Depending on the relative weight of linear versus nonlinear instability mechanisms associated to the single map two different scenarios for the transition may occur. When only two maps are considered we always find that the critical coupling $\epsilon_l$ for chaotic synchronization can be predicted within a linear analysis by the vanishing of the transverse Lyapunov exponent $\lambda_T$. However, major differences between transitions driven by linear or nonlinear mechanisms are revealed by the dynamics of the transient toward the synchronized state. As a representative example of extended systems a one dimensional lattice of chaotic maps with power-law coupling is considered. In this high dimensional model finite amplitude instabilities may have a dramatic effect on the transition. For strong nonlinearities an exponential divergence of the synchronization times with the chain length can be observed above $\epsilon_l$, notwithstanding the transverse dynamics is stable against infinitesimal perturbations at any instant. Therefore, the transition takes place at a coupling $\epsilon_{nl}$ definitely larger than $\epsilon_l$ and its origin is intrinsically nonlinear. The linearly driven transitions are continuous and can be described in terms of mean field results for non-equilibrium phase transitions with long range interactions. While the transitions dominated by nonlinear mechanisms appear to be discontinuous.Comment: 29 pages, 14 figure

Development of a video-assisted thoracoscopic lobectomy program in a single institution: Results before and after completion of the learning curve

BACKGROUND: The development of a video assisted thoracic surgery lobectomy (VATS-L) program provides a dedicated surgical team with a recognized learning curve (LC) of 50 procedures. We analyse the results of our program, comparing the LC with subsequent cases. METHODS: From June 2012 to March 2015, we performed n = 146 VATS major pulmonary resections: n = 50 (Group A: LC); n = 96 (Group B). Pre-operative mediastinal staging followed the National Comprehensive Cancer Network guidelines. All procedures were performed using a standard anterior approach to the hilum; lymphadenectomy followed the NCCN recommendations. During the LC, VATS-L indication was reserved to clinical stages I, therefore evaluated case by case. RESULTS: Mean operative time was 191 min (120-290) in Group A and 162 min (85-360) in Group B (p <0,01). Pathological T status was similar between two Groups. Lymphadenectomy included a mean of 5.8 stations in Group A and 6.6 in Group B resulting in: pN0 disease: Group A n = 44 (88 %), Group B n = 80 (83.4 %); pN1: Group A n = 3 (6 %), Group B n = 8 (8.3 %); pN2: Group A n = 3 (6 %), Group B n = 8 (8.3 %). Conversion rate was: 8 % in group A (n = 4 vascular injuries); 1.1 % in Group B (n = 1 hilar lymph node disease). We registered n = 6 (12 %) complications in Group A, n = 10 (10.6 %) in Group B. One case (1.1 %) of late post-operative mortality (90 days) was registered in Group B for liver failure. Mean hospital stay was 6.5 days in Group A and 5.9 days in Group B. CONCLUSIONS: We confirm the effectiveness of a VATS-L program with a learning curve of 50 cases performed by a dedicated surgical team. Besides the LC, conversion rate falls down, lymphadenectomy become more efficient, indications can be extended to upper stages