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No robust evidence is provided by literature regarding the management of intracranial hypertension following severe traumatic brain injury (TBI). This is mostly due to the lack of prospective randomized controlled trials (RCTs), the presence of studies containing extreme heterogeneously collected populations and controversial considerations about chosen outcome. A scientific society should provide guidelines for care management and scientific support for those areas for which evidence-based medicine has not been identified. However, RCTs in severe TBI have failed to establish intervention effectiveness, arising the need to make greater use of tools such as Consensus Conferences between experts, which have the advantage of providing recommendations based on experience, on the analysis of updated literature data and on the direct comparison of different logistic realities. The Italian scientific societies should provide guidelines following the national laws ruling the best medical practice. However, many limitations do not allow the collection of data supporting high levels of evidence for intracranial pressure (ICP) monitoring and decompressive craniectomy (DC) in patients with severe TBI. This intersociety document proposes best practice guidelines for this subsetting of patients to be adopted on a national Italian level, along with joint statements from "TBI Section" of the Italian Society of Neurosurgery (SINch) endorsed by the Neuroanesthesia and Neurocritical Care Study Group of the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI). Presented here is a recap of recommendations on management of ICP and DC supported a high level of available evidence and rate of agreement expressed by the assemblies during the more recent consensus conferences, where members of both groups have had a role of active participants and supporters. The listed recommendations have been sent to a panel of experts consisting of the 107 members of the "TBI Section" of the SINch and the 111 members of the Neuroanesthesia and Neurocritical Care Study Group of the SIAARTI. The aim of the survey was to test a preliminary evaluation of the grade of predictable future adherence of the recommendations following this intersociety proposal. The following recommendations are suggested as representing best clinical practice, nevertheless, adoption of local multidisciplinary protocols regarding thresholds of ICP values, drug therapies, hemostasis management and perioperative care of decompressed patients is strongly recommended to improve treatment efficiency, to increase the quality of data collection and to provide more powerful evidence with future studies. Thus, for this future perspective a rapid overview of the role of the multimodal neuromonitoring in the optimal severe TBI management is also provided in this document. It is reasonable to assume that the recommendations reported in this paper will in future be updated by new observations arising from future trials. They are not binding, and this document should be offered as a guidance for clinical practice through an intersociety agreement, taking in consideration the low level of evidence.

In the era of the internet of things (IoT), software-enabled inter-connected devices are of paramount importance. The embedded systems are very frequently used in both security and privacy-sensitive applications. However, the underlying software (a.k.a. firmware) very often suffers from a wide range of security vulnerabilities, mainly due to their outdated systems or reusing existing vulnerable libraries; which is evident by the surprising rise in the number of attacks against embedded systems. Therefore, to protect those embedded systems, detecting the presence of vulnerabilities in the large pool of embedded devices and their firmware plays a vital role. To this end, there exist several approaches to identify and trigger potential vulnerabilities within deployed embedded systems firmware. In this survey, we provide a comprehensive review of the state-of-the-art proposals, which detect vulnerabilities in embedded systems and firmware images by employing various analysis techniques, including static analysis, dynamic analysis, symbolic execution, and hybrid approaches. Furthermore, we perform both quantitative and qualitative comparisons among the surveyed approaches. Moreover, we devise taxonomies based on the applications of those approaches, the features used in the literature, and the type of the analysis. Finally, we identify the unresolved challenges and discuss possible future directions in this field of research.

Industrial Control Systems (ICSs) are cyber-physical systems that offer attractive targets to threat actors due to the scale of damages, both physical and cyber, that successful exploitation can cause. As such, ICSs often find themselves victims to reconnaissance campaigns - coordinated scanning activity that targets a wide subset of the Internet - that aim to discover vulnerable systems. As these campaigns likely scan broad netblocks of the Internet, some traffic is directed to network telescopes, which are routable, allocated, and unused IP space. In this paper, we explore the threat landscape of ICS devices by analyzing and investigating network telescope traffic. Our network traffic analysis tool takes darknet traffic and generates threat intelligence on scanning campaigns targeting ICSs in the form of campaign fragments, which we leverage in new ways to get more in-depth knowledge of the cybersecurity threats. We investigate the payloads of the identified campaigns using a custom Deep Packet Inspection (DPI) technique to dissect and analyze the packets. We found 13 distinct payload templates and deduced their purpose, and by extension the campaign goals. We use machine learning to classify the sources behind the campaigns and identify threat actors such as botnets, malicious attackers, or researchers, and establish a methodology to rank our campaigns to prioritize our analysis. To conduct our analysis of the threats targeting ICSs, we have leveraged 12.85 TB (330 days) of network traffic received by our observed darknet IP space. Combining these investigative threads, we provide a thorough overview of the threat landscape targeting ICS systems.

The rise of the Internet of Things (IoT) presents important challenges for future radio networks. Non-orthogonal multiple access (NOMA), which allows the network to support more than one user per orthogonal resource element, was recently proposed as a promising solution that can ultimately support the daunting requirements of such networks including massive connectivity, high spectral efficiency, and low latency. Nevertheless, numerous ultra-high-reliability applications of IoT present environments that are hampered by impulsive electromagnetic interference, referred to as impulsive noise. Such noise is known to cause degradation to the overall system performance. Moreover, given the non-orthogonal multiplexing in NOMA, such noise is expected to have a relatively more pronounced impact on the system performance. Therefore, this article sheds light on the performance degradation and mitigation of impulsive noise in the context of NOMA-based IoT networks. It proposes a multistage nonlinear processing approach specifically designed for OFDM-based PDM-NOMA systems. To obtain the optimum threshold of the corresponding users, we propose a deep learning approach to estimate the impulsive noise parameters from the received OFDM symbol. This information can consequently be used to evaluate the corresponding optimal threshold using Siegert's ideal observer criterion. Finally, this work sheds light on potential opportunities and challenges that are expected to arise during the implementation of NOMA in impulsive environments.

Impulsive noise, a common impediment preventing the system from achieving error-free transmission, is significant in many wireless and power line communication environments. Although the performance of several mitigation techniques for orthogonal frequency division multiplexing (OFDM)-based multicarrier communication systems impaired by memoryless impulsive noise are widely acknowledged, we note that OFDM is outperformed by its single-carrier counterpart when the impulses are very strong and/or they occur frequently, which is likely to exist in contemporary communication systems including smart grid communications. On the other hand, many communication technologies used in the smart grid do not employ OFDM and likewise, the assumption of memoryless noise is not valid for such communication scenarios. Memoryless noise models cannot take into account one of the main features of the actual noise, i.e., the time-correlation among the noise samples. The aim of this article is to compare and analyze several mitigation techniques such as clipping, blanking, and combined clipping-blanking to mitigate the noxious effects of bursty impulsive noise for low-density parity-check coded single-carrier communication systems. Moreover, we propose a log-likelihood ratio (LLR)-based impulsive noise mitigation for the considered scenario. In this context, provided simulation results highlight the superiority of the LLR-based mitigation scheme over the clipping/blanking schemes.

Impulsive noise is a common impediment in many wireless, power line communication (PLC), and smart grid communication systems that prevents the system from achieving error-free transmission. To overcome the detrimental effects of such impulsive interference, knowledge of impulsive noise parameters is generally required by the available mitigation techniques. This work considers a machine learning perspective for the estimation of the impulsive noise parameters in communication systems under the influence of Middleton class-A noise. Precisely, we consider a deep learning approach and design a deep neural network (DNN) that classifies a set of received symbols according to the parameters of the impulsive noise affecting them. It is sown that the classification accuracy greatly depends on the number of symbols fed into the neural network as well as the number of considered states in the classification, where the proposed approach can reach a testing accuracy of more than 99%.

A smarter power grid can improve the maintenance system by providing a real-time measurement of equipment operating conditions. Such a monitoring system requires the deployment of an increased number of sensors. However, the wiring sensors in a high voltage environment such as power substation is a very expensive procedure. An autonomous wireless sensor network can reduce the installation cost and make sensors more viable throughout the network. In this paper, we study the possibility of deploying an autonomous wireless sensor network in a substation environment. To this end, we merge energy harvesting and wireless transfer of energy to propose a hierarchical energy harvesting model. In this paper, we show that despite of the wasteful nature of the wireless transfer of energy and with an efficiency not more than what existing technologies can provide, a self-sustainable wireless sensor network in a substation area can be accomplished.

Inherent interfering signals generated by the underlying elements found in power substations have been known to span over consecutive noise samples, resulting in bursty interfering noise samples. In the impulsive noise environments, we elaborate a space-sensitive technique using multiple-input multiple-output (MIMO), which is particularly well suited in these usually very difficult situations. We assume the availability of channel state information (CSI) at the transmitter to achieve typical MIMO system gains in ad hoc mode. In this paper, we show that more than 10 dB gains are obtained with the most efficient system that we propose for achieving smart grid application requirements. On the one hand, the results obviously illustrate that the max-dmin precoder associated with the rank metric coding scheme is especially adapted to minimize the bit error rate (BER) when a maximum likelihood (ML) receiver is employed. On the other hand, it is shown that a novel node selection technique can reduce the required nodes transmission energies.

Industrial Control Systems (ICS) are attractive targets to attackers because of the significant cyber-physical damage they can inflict. As such, they are often subjected to reconnaissance campaigns aiming at discovering vulnerabilities that can be exploited online. As these campaigns scan large netblocks of the Internet, some of the IP packets are directed to the darknet, routable, allocated and unused IP space. In this paper, we propose a new technique to detect, fingerprint, and track probing campaigns targeting ICS systems by leveraging a /13 darknet traffic. Our proposed technique detects, automatically, and in near-real time such ICS probing campaigns and generates relevant and timely cyber threat intelligence using graph-theoretic methods to compare and aggregate packets into campaigns. Besides, it ascribes to each observed campaign a fingerprint that uniquely characterizes it and allows its tracking over time. Our technique has been tested over 12.85 TB of data, which represents 330 days of darknet network traffic received. The result of our analysis allows for the discovery of not only known legitimate recurrent probing campaigns such as those performed by Shodan and Censys but also uncovers coordinated campaigns launched by other organizations. Furthermore, we give details on a campaign linked to botnet activity targeting the EtherNet/IP protocol.

In last chapters, an overview of electromagnetic interference induced by partial discharges and their impact on wireless communication systems has been discussed. Measurement campaigns in substations have been conducted. These sources can take place in high-voltage equipment like transformers, powerlines, bushing bars, etc.

This chapter gives a general overview of EMI and describes the measurement and characterization methods associated with them, in keeping with the latest research. Impulsive noise phenomenon in substations is particularly focused and existing impulsive noise models are discussed.

In Chaps. 4– 6 accurate impulsive noise models have been proposed. These can be used for performance analyses of robust wireless communication systems as well as the development of diagnostic tools in high voltage equipments. The development of rapid and online methods of detection, identification and/or localization of partial discharge (PD) sources using wireless intelligent electronic devices is an area of growing interest.

There is a widespread adoption of intelligent electronic devices (IEDs) in modern-day smart grid deployments. Consequently, any vulnerabilities in IED firmware might greatly affect the security and functionality of the smart grid. Although general-purpose techniques exist for vulnerability detection in firmware, they usually cannot meet the specific needs, e.g., they lack the domain knowledge specific to IED vulnerabilities, and they are often not efficient enough for handling larger firmware of IEDs. In this paper, we present BinArm, a scalable approach to detecting vulnerable functions in smart grid IED firmware mainly based on the ARM architecture. To this end, we build comprehensive databases of vulnerabilities and firmware that are both specific to smart grid IEDs. Then, we propose a multi-stage detection engine to minimize the computational cost of function matching and to address the scalability issue in handling large IED firmware. Specifically, the proposed engine takes a coarse-to-fine grained multi-stage function matching approach by (i) first filtering out dissimilar functions based on a group of heterogeneous features; (ii) further filtering out dissimilar functions based on their execution paths; and (iii) finally identifying candidate functions based on fuzzy graph matching. Our experiments show that BinArm accurately identifies vulnerable functions with an average accuracy of 0.92. The experimental results also show that our detection engine can speed up the existing fuzzy matching approach by three orders of magnitude. Finally, as a practical framework, BinArm successfully detects 93 real-world CVE vulnerability entries, the majority of which have been confirmed, and the detection takes as little as 0.09 s per function on average.

The design of robust receivers in environments with strong impulsive noise may be challenging due to their high-amplitude events and their rare but nonnegligible occurrence. In substation environments, these impulsive noises are predominant. They are induced by corona discharges such as electrical arcs or partial discharges in the air. The emitted radiations can occupy a wide range of frequencies typically reaching a few gigahertz with very high amplitude. In this paper, we develop a generalized model of impulsive electromagnetic interference induced by corona discharges for wireless channels. Radiations emitted by these sources are generally transient impulses, their occurrences follow cyclostationary process, due to their generation by an alternative current. In this model, we both take into account the physical mechanism of these discharges and the induced electromagnetic radiations. Experimental results validate the approach in terms of first- and second-order statistics such as amplitudes, interarrival time, occurrences, and power spectrum densities of impulsive transient noise.

A technique for the fast identification of partial discharge (PD) sources is proposed for the detection of mechanical failure or damage to insulation materials by using wireless remote control and monitoring systems in substations. An estimation of the number of PD sources can help to evaluate the insulation performance and lifetime of power equipment. Multiple PD sources can be generated during the operating voltage where their electromagnetic radiations are highly impulsive, non-Gaussian noise and the resulting probability distribution function is heavy-tailed. Multiple PD sources can be estimated by their electromagnetic radiations via blind source separation (BSS) and measuring the excess kurtosis using low-cost wireless intelligent electronic devices. The efficiency and performance of the proposed method is demonstrated by simulating PD sources based on the spatial Poisson point process where the number of sources is a random variable not known by the receiver. Assuming non-white and decorrelated or non-Gaussian and independent sources, results show that the number of significant PD sources can be estimated with low error rate. Underdetermined problems in BSS can affect performances.

The installation of wireless technologies in power substations requires characterizing the impulsive noise produced by the high-voltage equipment. Substation impulsive noise might interfere with classic wireless communications and none of the existing models can reliably represent this noise in wide band. Previous studies have shown that impulsive noise is characterized by series of damped oscillations with the amplitude, the duration and the occurrence times of the impulses that are random. All these characteristics make this noise time-correlated and the partitioned Markov chain remains an efficient model that can ensure the correlation between the samples. In this study, we propose to design a partitioned Markov chain to generate an impulsive noise that is similar to the noise measured in existing substations, in time and frequency domains. We configure our Markov chain to produce the impulses with the damped oscillation effect, then, we determine the probability transition matrix and the distribution of each state of the Markov chain. Finally, we generate noise samples and we study the distribution of the impulsive noise characteristics. Our Markov chain model can replicate the correlation between the measured noise samples; also the distributions of the noise characteristics are similar in the simulations and the measurements.

Installing wireless Intelligent Electronic Devices (IED) for Substation Automation (SA) requires a thorough study of the electromagnetic radiations coming from the power equipment. In our previous work, we have performed a measurement campaign within several substations working under different voltages and we have recorded around 120 sequences of impulsive noise samples in the 700 MHz–2.5 GHz band. In this paper, we present a method to classify substation impulsive noise in order to characterize a representative Radio Frequency (RF) environment of substations for specific substation voltages. The main contribution of this work is to provide representative impulsive noise characteristics in order to calculate parameters for impulsive noise models and to improve the characterization of substation RF noise. To reach this objective, we classify impulsive noise characteristics, such as the impulse amplitude, the impulse duration and the repetition rate for substations under 25 kv, 230 kV, 315 kV and 735 kV. By using the impulsive noise characteristics, we estimate representative parameters for two impulsive noise models: the Middleton class-A (MCA) and the Bernoulli-Gaussian with memory (BGM).

Power utilities around the world are modernizing their grid by adding layers of communication capabilities to allow for more advanced control, monitoring and preventive maintenance. Wireless Sensor Networks (WSNs), due to their ease of deployment, low cost and flexibility, are considered as a solution to provide diagnostics information about the health of the connected devices and equipment in the electrical grid. However, in specific environments such as high voltage substations, the equipment in the grid produces a strong and specific radio noise, which is impulsive in nature. The robustness of off-the-shelf equipment to this type of noise is not guaranteed; it is therefore important to analyze the characteristics of devices, algorithms and protocols to understand whether they are suited to such harsh environments. In this paper, we review several WSN standards: 6LoWPAN, Zigbee, WirelessHART, ISA100.11a and OCARI. Physical layer specifications (IEEE 802.15.4) are similar for all standards, with considerable architectural differences present in the higher layers. The purpose of this paper is to determine the appropriate WSN standard that could support reliable communication in the impulsive noise environment, in electrical substations. Our review concludes that the WirelessHART sensor network is one of the most suitable to be implemented in a harsh impulsive noise environment.

Power substations constitute a unique environment where the wireless medium is corrupted by impulsive electromagnetic interference. Conventional receivers are designed to operate in typical environments where the noise is assumed to be a white Gaussian noise. Hence, using conventional receivers in power substation environments may result in poor performance. To design reliable communication system, we must consider a receiver that is more adapted to these particular environments. In this paper, we first start by extending a single antenna impulsive interference model to a multi-antenna scenario. Then, we introduce a new receiver that is more suitable to the studied environment. This receiver takes advantage of multi-antenna at the receiver side to mitigate the interference. Simulations show that using the proposed approach gives significant performance upgrade compared to the conventional Gaussian receiver.

Impulsive noise in air-insulated substations is created by partial discharges, Corona and gap noises. In order to install a wireless sensors network in such an environment, the impulsive noise must be characterized and studied to predict its evolution. The first observations made during a measurement campaign in power substation indicate impulsive noise RF characteristics depends on the feeding voltage of the equipment. In laboratory, a test bench with impulsive noise sources has been designed and used in order to verify the assumptions made from measurement campaigns and partial discharge theory. Using two impulsive noise specimens, the generator bar and the Tesla-coil, we study the impact of the source voltage and the inter-electrode distance (gap) on the RF characteristics of the emitted impulsive noise. The experiences confirm that, when the feeding voltage increases, the noise becomes more powerful both in time and frequency domains. The same is observed when the gap becomes shorter. Furthermore, the ISM frequency content of impulsive noise also increases, which could severely affect wireless communications.

Microwave telecommunications links are severely influenced by the frequency and climatic parameters as refractivity gradient (dN1), geoclimatic factor (K), rain, temperature, pressure, and humidity. This influence increases with the frequency of the wave. In microwave band, recent research has shown that the geoclimatic factor (K), rain and temperature are the most important parameters affecting the performance of terrestrial links. K is an important parameter as directly proportional to the worst month outage probability P w . K depends on the refractivity gradient dN1. The dN1 depends itself on the pressure, the temperature and the humidity. In this paper, we demonstrated from the data of the terrestrial links located in Quebec, Canada, that there is a seasonal variation of the geoclimatic factor, K mes . This variation of K mes is mainly due to the variation of the humidity. The variation of the geoclimatic factor is not limited to the seasonal variation. But it is true from one year to another. IUT recommendations do not embed climate change, but assume a stationary climate. We recommend to improve data analysis and predictive models by taking into account the temporal changes.

The use of wireless technologies in high voltage environments is increasing with the growing need for monitoring and preventive maintenance in electricity utilities. The feasibility of deploying wireless technologies in high voltage environments such as substations is addressed in this paper. High voltage substations are different from common area due to the presence of many metallic structures causing multiple reflexions, diffractions and scattering. The simulations are performed using realistic substations representation and up-to-date radio equipments specifications. The propagation coverage and the maximum throughput achievable are presented for three wireless technologies, WiFi, WiMAX and 900 MHz systems. The simulation results are discussed and some recommendations are given. Note that the impact of impulsive noise such as partial discharges is not addressed in this paper which only focuses on the evaluation of wireless systems under specific multipath scenario of substations.

To satisfy the smart grid electrical network, communication systems in high-voltage substations have to be installed in order to control equipments. Considering that those substations were not necessarily designed for adding communication networks, one of the most appropriate solutions is to use wireless sensor network (WSN). However, the high voltage transported through the station generates a strong and specific radio noise. In order to prepare for such a network, the electromagnetic environment has to be characterized and tests in laboratories have to be performed to estimate the communication performances. This paper presents a method for measuring the noise due to high voltage and more particularly the impulsive noise. In the laboratory, we generate the impulsive noise using two specimens, and we show that these laboratory measurements validate the field measurements of Pakala et al. For the two specimens, it aims to link the noise characteristics (magnitude and frequency) with the specimen parameters (power supply and geometric dimensions) to predict the environments where wireless communications can be troublesome. By using different sets of this measured noise, we show that the statistical model of Middleton Class A can be used to model the impulsive noise in high-voltage substations better than the Gaussian model. We consider a cooperative multiple-input-multiple-output (MIMO) system to achieve the wireless sensor communication. This system uses recent MIMO techniques based on precoding like max-d min and P-OSM precoders. The MIMO precoder-based cooperative system is a potential candidate for energy saving in WSN since energy efficiency optimization is a very important critical issue. Since MIMO precoders are with Gaussian noise assumption, we evaluate the performance of several MIMO precoders in the presence of impulsive noise using estimated parameters from the measured noise.

The channel capacity and the channel statistics are both important performance metrics to consider for appropriate design of wireless systems. In tactical mobile ad hoc networks environment, the capacity and the second order statistics are investigated based on an optimized physical layer simulation tool which includes tactical scenarios generator and propagation modeler. The possible link data rate is stemmed from the average channel capacity analysis between all pair of nodes. And based on the minimum data rate requirement for typical services (web, audio and video streaming, VoIP, videoconference), connectivity graphs are constructed. Moreover, level cross rate (ICR) and average duration of fade (ADF) are simulated as function of double mobility degree and the results show how the double mobility affects the second order channel statistics and the error probability.

Recently, research topics are focusing on clustering approaches for Ad hoc networks due to their effectiveness in building a virtual backbone formed by a set of suitableclusterheads (CH) to guarantee the communications acrossclusters. In this paper, we propose a clustering approach to elect suitable nodes’ representatives and to store minimum topology information by reducing the propagation of routing information which facilitates the spatial reuse of resource and increase the system capacity. The clusters must adapt dynamically to the environment changes, we also propose a distributed maintenance procedure that allows managing nodes’ adhesion, nodes’ handoff and CHs’ re-election. Based on our analytical model used to estimate the quality of service (QoS) parameters, we implement an admission control algorithm to determine the number of members inside a cluster that can be accommodated while satisfying the constraints imposed by the current applications. This might effectively drive congestion avoidance on the CH andinterclusters load-balancing to achieve better network resource utilization. The obtained results will help us to readjust the clustering algorithm metrics in order to provide better maintenance and QoS guarantees depending on the used applications. Through numerical analysis and simulations, we have studied the performance of our model and compared it with that of other existing algorithms. The results demonstrate better performance in terms of number of clusters, number of handoffs, number of transitions (state change) on CHs, QoS parameters, load balancing and scalability. We also observed how the connectivity and the stability are maximized when the number of nodes increases in presence of the mobility.

The bit error rate is an important metric to consider when analysing performance of wireless system. The mobile-to-mobile channels are quite different from fixed-to-mobile channels especially the power spectral density of the Doppler spread. This paper proposes the performances simulation of M2M channel in ad hoc networks context. The simulations are carried out using a realistic channel model and a DQPSK modulation with differential detection. The results show the effect of double mobility degree on bit error rate.

Simulation tools are very helpful for cost-effective design of wireless networks and useful to have better understanding of many phenomena. Ad hoc networks are one of the complex wireless systems because of the difficult to have good prediction in their topology changing. Our contribution in this paper is to provide as well as possible the best description of ad hoc scenarios in order to have a better analysis of the physical layer, and finally to improve performances of the whole network. We have created a scenarios generator to be able to generate a large number of scenarios with the same set of parameters or various scenarios. To meet some requirements of military use (which is our main application) we have proposed improvements of some classic mobility models. Many figures are depicted to illustrate our approach. And finally, we present the results in term of channel behaviour while coupling the generator with a semi-deterministic propagation model.

Clustering has been proven to be a promising approach for mimicking the operation of the fixed infrastructure and managing the resources in multi-hop networks. In order to achieve good performance, the formation and maintenance procedure of clusters should operate with minimum overhead, allowing mobile nodes to join and leave without perturbing the membership of the cluster and preserving current cluster structure as much as possible. In this paper, we propose a Flexible Weight Based Clustering Algorithm (FWCA) in Mobile Ad hoc Networks. The goals are yielding low number of clusters, maintaining stable clusters, minimizing the number of invocations for the algorithm and maximizing lifetime of mobile nodes in the system. Through simulations we have compared the performance of our algorithm with that of WCA in terms of the number of clusters formed, number of re-affiliations, number of states transitions on each clusterhead and number of clusterheads changes. The results demonstrate the superior performance of the proposed algorithm.

Brain gliomas require a deep knowledge of their effects on brain connectivity. Understanding the complex relationship between tumor and functional brain is the preliminary and fundamental step for the subsequent surgery. The extent of resection (EOR) is an independent variable of surgical effectiveness and it correlates with the overall survival. Until now, great efforts have been made to achieve gross total resection (GTR) as the standard of care of brain tumor patients. However, high and low-grade gliomas have an infiltrative behavior and peritumoral white matter is often infiltrated by tumoral cells. According to these evidences, many efforts have been made to push the boundary of the resection beyond the contrast-enhanced lesion core on T1w MRI, in the so called supratotal resection (SpTR). SpTR is aimed to maximize the extent of resection and thus the overall survival. SpTR of primary brain tumors is a feasible technique and its safety is improved by intraoperative neuromonitoring and advanced neuroimaging. Only transient cognitive impairments have been reported in SpTR patients compared to GTR patients. Moreover, SpTR is related to a longer overall and progression-free survival along with preserving neuro-cognitive functions and quality of life.

Hemostasis represents a fundamental step in every surgical procedure. During neurosurgical procedures, proper and robust hemostasis into confined spaces can significantly reduce the odds of perioperative complications. Over the decades, multiple methods have been applied, and several medical devices have been developed to promote and guarantee proper hemostasis. This study presents a systematic review of the most used intraoperative hemostatic methods and devices in neurosurgery. Insightful research was performed on the PubMed database according to the PRISMA guidelines. This comprehensive review of scientific literature represents a synoptic panel where the most used intraoperative hemostatic methods and devices available today in neurosurgery are classified and described.

Background: Because the neurological presentation of spinal epidural hematomas (SEH) is often not specific, they may be misdiagnosed as acute lumbar disk herniations. Here, we present a case in which a traumatic disc extrusion mimicked an epidural hematoma and reviewed the appropriate literature. Case Description: A 27-year-old male sustained a high-energy fall. The lumbar MRI scan showed a L4-S1 ventral medium/high signal intensity mass on the T1- and high signal intensity lesion on T2-weighted images; the original diagnosis was spinal epidural hematoma. However, at surgery, consisting of a left L4 and L5 hemilaminectomy with L4-L5 and L5-S1 laminotomy, an extruded lumbar disc was encountered at the L4-L5 level and removed; no additional pathology or SEH was found at either level. Conclusion: On MR, SEH may mimic acute lumbar disk herniations. Depending on the clinical symptoms/signs, surgical intervention will both correctly confirm the diagnosis and relieve neural compression.

The spread of the SARS-CoV-2 infection among population has imposed a re-organization of healthcare services, aiming at stratifying patients and dedicating specific areas where patients with suspected COVID-related respiratory disease could receive the necessary health care assistance while waiting for the confirmation of the diagnosis of COVID-19 disease. In this scenario, the pathway defined as a “grey zone” is strongly advocated. We describe the application of rules and pathways in a regional context with low diffusion of the infection among the general population in the attempt to provide the best care to respiratory patients with suspected COVID-19. To date, this process has avoided the worst-case scenario of intra-hospital epidemic outbreak.

Background: Therapeutic epidural spinal injections (ESIs) of steroids are one of the most common nonsurgical management modalities employed for alleviating pain due to chronic persistent lumbar spinal disease. However, it is well documented that they have significant risks and complications without any long-term efficacy. ESI may result in epidural empyema which may be difficult to diagnose with delays resulting in significant permanent neurological sequelae. Case Description: A 45-year-old female presented with a lumbar spinal epidural empyema after receiving ESI for low back and right leg pain due to a lumbar disc herniation. Laboratory studies showed elevations of multiple inflammatory markers, and the MR documented a significant lumbar epidural empyema contributing to significant thecal sac compression. Clinically, the patient had an acute cauda equina syndrome warranting emergency surgery consisting of a laminectomy for debridement/decompression followed by long-term antibiotic treatment. Conclusion: Epidural empyema is a major potential complication of lumbar ESI. Multiple markedly elevated inflammatory markers (WBC, ESR, CRP, and procalcitonin) and MRI evidence of an epidural empyema necessitates emergent surgical intervention to limit morbidity, neurological sequelae, and mortality.

Background Lumbar spinal stenosis (LSS) is a narrowing of the spinal canal due to spinal degeneration, and its main clinical symptom is neurogenic claudication. Surgical treatment is pursued for patients who do not improve with conservative care. Patients with symptomatic LSS who also have significant medical comorbidities, although clearly in need of intervention, are unattractive candidates for traditional open lumbar decompressive procedures. Thus it is important to explore minimally invasive surgical techniques to treat select patients with LSS. Methods This retrospective case series evaluated the clinical and radiographic outcomes of a new minimally invasive procedure to treat LSS: pedicle-lengthening osteotomy using the ALTUM system ((Innovative Surgical Designs, Inc., Bloomington, Indiana, United States). Peri- and postoperative demographic and radiographic data were collected from a clinical series of seven patients with moderate LSS who were > 60 years of age. Clinical outcome was evaluated using visual analog scale (VAS) scores and the spinal canal area on computed tomography scans. Results Twelve months after the procedure, scoring revealed a median improvement of 3.7 on the VAS for the back and 6.3 on the VAS for the leg, compared with the preoperative baseline (p Conclusions In this preliminary study, the ALTUM system showed a good clinical and radiologic outcome 1 year after surgery. In an older or high-risk population, a short minimally invasive procedure may be beneficial for treating LSS.

Cerebral abscess following cholesteatomatous otomastoiditis is a life-threatening complication and poses diagnostic and therapeutic challenges. We report a case of life-threatening cerebritis and cerebral abscess due to a collection of pus from an aerobic super infections occurring months after the apparent resolution of an otogenic brain abscess in a 67-year-old immunocompetent Italian female. Two gram-positive anaerobic pathogens were isolated during secondary neurosurgical procedures and antibiotic treatment was adopted to resolve the complications. Another objective of this study was to review the literature on gram-positive anaerobic pathogens and brain abscess complications in patients with fistula, and to highlight the importance of short imaging in monitoring treatment during long-term antibiotic therapy for otogenic brain abscess to avoid abscess recurrence. Isolating the strain and monitoring response to treatment with magnetic resonance imaging may improve the prognosis. The study also highlights the need for a close cooperation between infectious disease consultants and neurosurgeons.

Background Chagas disease is endemic in Latin America and affects 8 million people worldwide. In 2010, Catalonia introduced systematic public health surveillance to detect and treat congenital Chagas disease. Aim The objective was to evaluate the health outcomes of the congenital Chagas disease screening programme during the first 6 years (2010–2015) after its introduction in Catalonia. Methods In a surveillance system, we screened pregnant women and newborns and other children of positive mothers, and treated Chagas-positive newborns and children. Diagnosis was confirmed for pregnant women and children with two positive serological tests and for newborns with microhaematocrit and/or PCR at birth or serology at age 9 months. Results From 2010 to 2015, the estimated screening coverage rate increased from 68.4% to 88.6%. In this period, 33,469 pregnant women were tested for Trypanosoma cruzi and 937 positive cases were diagnosed. The overall prevalence was 2.8 cases per 100 pregnancies per year (15.8 in Bolivian women). We followed 82.8% of newborns until serological testing at age 9–12 months and 28 were diagnosed with Chagas disease (congenital transmission rate: 4.17%). Of 518 siblings, 178 (34.3%) were tested and 14 (7.8%) were positive for T. cruzi. Having other children with Chagas disease and the heart clinical form of Chagas disease were maternal risk factors associated with congenital T. cruzi infection (p Conclusion The increased screening coverage rate indicates consolidation of the programme in Catalonia. The rate of Chagas disease congenital transmission in Catalonia is in accordance with the range in non-endemic countries.

Urinary incontinence (UI) is defined as a loss of bladder control and is characterized by the complaint of any involuntary leakage of urine. Evidence suggests that the prevalence of UI is higher in subjects with chronic obstructive pulmonary disease (COPD) than in age-matched controls in both sexes. UI is classified as stress, urge, and mixed, and has a considerable impact on quality of life. However, the prevalence of UI in individuals with COPD is mostly unexplored in clinical research and often underestimated in clinical practice. Interestingly, although the involuntary leakage of a small amount of urine during coughing (e.g., stress UI) is among the most plausible causes of UI in patients with COPD, its importance has been questioned by some researchers. Moreover, UI as a respiratory drug-related adverse effect is largely overlooked; only a few randomized controlled trials have reported the presence of urinary symptoms, mainly as urinary retention due to anticholinergic agents. In this narrative review, we explored whether, and to what extent, UI occurs in COPD individuals, and what the proposed actions to improve this condition are. We found that the association between UI and COPD is largely unexplored, mostly because UI tends to be attributed to older age. We infer that the prevalence of UI in individuals with chronic respiratory symptoms is often underestimated in clinical practice. The misinterpretation of urinary symptoms as related to the respiratory condition can delay diagnostic and therapeutic approaches. The use of simple self-administered questionnaires to assess the presence of UI is encouraged.

Background: The craniovertebral junction (CVJ) can be affected by a variety of congenital or acquired anomalies. Because of its complexity, a careful evaluation of bones and ligamentous structures in all three planes is required. This can be achieved by studying the CVJ in terms of several anatomical and radiological lines that have been visualized to facilitate understanding of its surgical anatomy. In this study we aimed to review the state-of-the art craniometric CVJ lines and approaches. Methods: In December 2016 a PubMed search was performed, including the search terms ‘CVJ surgical approach/line’, ‘cervical approach’, ‘craniometric measurement’, ‘CVJ anatomy’ and ‘ventral/dorsal/far-lateral approach’. Anatomical and radiological lines and angles evaluated on traditional radiography, computed tomography (CT) scanning or magnetic resonance imaging (MRI) in the axial/sagittal/coronal views were included and described. Results: Several measurements and radiological landmarks were included to evaluate the anatomy of the CVJ. They were fully described and categorized on the basis of the anatomical plan and the surgical or diagnostic purpose they are used for. Conclusion: Among the numerous radiological measurements described, it has been shown that McRae’s line, Chamberlain’s line, McGregor’s line, the Redlund-Johnell method and Ranawat’s line are the most widely used and reliable ones for evaluating skull base craniometry. Secondly, the hard palate line (HPL), nasoaxial line (NAxL) and palatine–inferior dental arch line (PIA) are used to preoperatively assess the ventral endonasal or transoral surgical approaches. Thirdly, the C7 slope has been demonstrated as a reliable predictor of occipitocervical and spinopelvic alignment in CVJ fusion.

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.

Background: Cranioplasty (CP) is a widespread surgical procedure aimed to restore skull integrity and physiological cerebral hemodynamics, to improve neurological functions and to protect the underlying brain after a life-saving decompressive craniectomy (DC). Nevertheless, CP is still burdened by surgical complications, among which early or late graft infections are the most common outcome-threatening ones. Case Description: We report the case of 48-year-old man admitted to our neurosurgical unit because of a painful right frontal swelling and 1-week purulent discharge from a cutaneous fistula. He had been undergone frontal CP because of severe traumatic brain injury (TBI) when he was 9-year-old. Since then, his medical history has been being unremarkable without any surgical or infective complication of the graft for 39 years, until he was accidentally stung by a hornet in the frontal region. After the CT scan and laboratory findings had evidenced a probable infection of the graft, the patient was treated by vancomycin and cefepime before he underwent surgical revision of its former CP, with the removal of the graft and the debridement of the surgical field. Subsequent bacteriological tests revealed Staphylococcus aureus as causal agent of that infection. Conclusion: This case illustrates an anecdotal example of very late CP infection, due to an unpredictable accident. Due to lack of consensus on risk factors and on conservative or surgical strategy in case of graft infection, we aimed to share our surgical experience.

Background: Merkel cell carcinoma (MCC) is a rare neuroendocrine skin tumor, which may be related to sun exposure. It can metastasize to lungs, liver and bone, leading to severe morbidity and mortality. Vertebral metastases from MCC are rare. The authors report the tenth case in the literature, a 59-year-old patient with MCC, which was primarily localized in the scalp, and later provoked distant metastasis to the thoracic spinal column. Case Description: A 59-year-old woman was admitted at our Unit of Neurosurgery with a 4-month history of progressive and severe dorsal back pain, without neurological signs. The patient had been surgically treated for a recidivated MCC in the occipital region in 2007, 2011, and 2013. (In 2013, the surgical treatment also included lateral cervical lymph node dissection). Chemotherapy and radiotherapy had come after the treatments. Magnetic resonance imaging (MRI) of the dorsal spine showed metastatic vertebral involvement with cord impingement of the T7-T8 levels. A total body CT scan revealed lungs and liver metastases, besides vertebral district. After a multidisciplinary consult a palliative surgery was decided and a posterior dorsal approach was employed: Radiofrequency (RF) thermoablation was followed by the injection of cement of T7 and T8 and transpedicle fixation T5-T9. The postoperative course was uneventful and followed by a further adjuvant therapy Conclusion: Spinal metastases from MCC are described in literature only exceptionally. The clinical course is presented, along with a review of literature.

Background: Chronic low back and leg pain is a disabling condition, affecting, in most cases, older patients with congenital or acquired spinal stenosis or patients with failed back surgery syndrome. Spinal cord stimulation has been introduced as an effective therapeutic option for those patients who have previously been operated without significant clinical benefits, or for all those patients who are ineligible for traditional surgery. Methods: We report our experience with ten patients treated with spinal cord stimulation plus medication and physical therapy between November 2014 and September 2015. Inclusion criteria were: previous surgical treatments for lumbar stenosis and metameric instability and persistent or ingravescent disabling low back and leg pain, with a mean duration of symptoms of at least 18 months. A visual analog scale (VAS) was employed for back and leg pain, and the Oswestry Disability Index (ODI) score was determined, and findings were analyzed after 6 months. Findings: No intra- or postoperative complication was recorded. The mean VAS score for back pain decreased from 7.5 to 2.9, while leg VAS decreased from 8.2 to 3.0. Analysis of ODI values showed evident improvement in daily life activities, ranging from a median value of 75.7% to 32.7 % after the stimulation. Conclusion: Spinal cord stimulation has a recognized impact on the pain and on the quality of life of patients with failed back surgery syndrome.

Background: Painful spinal metastases usually occur in malignant neoplastic disease. Treatment for bone metastases has been largely conservative, and it includes the use of high doses of analgesics, radiotherapy, chemotherapy, hormone therapy, and bisphosphonates; however, results are sometimes transient and ineffective. In the presence of neurological involvement a surgical strategy should be considered. Recently, percutaneous procedures such as radiofrequency ablation, vertebroplasty, and kyphoplasty have been introduced as palliative techniques to treat painful vertebral metastases [3, 11, 25]. Methods: In our study we combined the use of radiofrequency ablation with vertebroplasty in the treatment of dorsolumbar metastatic vertebral fractures in order to examine the relationship between restoration of the vertebral structure and decrease in pain. From January 2014 to March 2015 we retrospectively analyzed 18 patients with malignant vertebral lesions who underwent radiofrequency ablation with vertebroplasty followed by cementoplasty, with posterior transpedicle fixation on levels near the lesions. The parameters examined were: demographics, pain relief, and the distribution of polymethylmethacrylate (PMMA) determined by the mean Saliou filling score; all complications were recorded. Findings: The mean age of the patients was 55.72 years (range 34-69); average operative time was 60.4 min (range, 51-72). The average pain index score (visual analog score; VAS) decreased significantly from 8.05 at baseline to 3.0 (p < 0.05) after 6 months. The Saliou filling score revealed a distribution of PMMA in the vertebral body that was satisfactory (12-18) in eight patients, mediocre (6-12) in seven patients, and inadequate (0-6) in the remaining three patients. In two vertebrae, minimal asymptomatic cement leakage occurred in the lateral recess without neurological damage. No pulmonary embolism and no visceral or neural damage was recorded. Conclusion: Radiofrequency ablation combined with vertebroplasty seems to achieve rapid and lasting improvement in clinical symptoms in patients with malignant vertebral lesions. There was wide diffusion of PMMA in the vertebral body, with a mean cement volume of 4.5 ml.

Background: Percutaneous techniques have increasingly gained popularity in recent years. The application of technological innovation, including neuromonitoring techniques, has the potential to increase the safety and efficacy of these procedures. Methods: Thirty patients suffering from osteoporotic dorsolumbar burst fracture were prospectively enrolled in this study. The patients underwent percutaneous fenestrated pedicle screw fixation augmented with polymethylmethacrylate (PMMA) injection. A novel surgeon-dedicated neuromonitoring device was used in order to increase the safety and the accuracy of the screw insertion. A second group of 30 patients who did not undergo neuromonitoring during percutaneous pedicle screw placement, matched for demographic characteristics, constituted the control group. Findings: A total of 296 screws were inserted. All treated patients had a good outcome, documented by an improvement in visual analogue scale (VAS) scores. Excellent trajectories were achieved in all patients. Cobb’s angle and anterior vertebral height were satisfactorily restored in all study group patients. Three misplaced screws in three patients and a case of PMMA leakage without neurological deficits were observed in the control group, whereas no complication was recorded in the study group (p = 0.03). Conclusions: Neuromonitoring in cement-augmented percutaneous pedicle screw placement appears to improve surgeon confidence during surgery, reducing the risk of screw misplacement or cement leakage.

Background Epidural hematomas, cerebrospinal fluid fistula, and spinal infections are challenging postoperative complications following vertebro-spinal procedures. We report our preliminary results using autologous fibrin sealant as both fibrin glue and a hemostatic during these operations. Methods Prospectively, between January 2013 and March 2015, 68 patients received an autologous fibrin sealant prepared with the Vivostat(®) system applied epidurally to provide hemostasis and to seal the dura. The surgical technique, time to bleeding control, and associated complications were recorded. Results Spinal procedures were performed in 68 patients utilizing autologous fibrin glue/Vivostat(®) to provide rapid hemostasis and/or to seal the dura. Only 2 patients developed postoperative dural fistulas while none exhibited hemorrhages, allergic reactions, systemic complications, or infections. Conclusions In this preliminary study, the application of autologous fibrin sealant with Vivostat(®) resulted in rapid hemostasis and/or acted as an effective dural sealant. Although this product appears to be safe and effective, further investigations are warranted.

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 fibrin 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.

Study design: Case report. Objectives: We report a case of a 75-year-old woman suffering from voluminous idiopathic spontaneous spinal epidural hematoma (SSEH) that was rapidly diagnosed and successfully treated. Methods: Clinical presentation was characterized by sudden and intense back pain that rapidly evolved into plegia of the right leg and severe paresis of the left leg. Hypoesthesia below T6 and urinary retention were also present. Magnetic resonance imaging showed a significant posterior spinal compression from T6 through L3 caused by an epidural hematoma that involved 10 metameric levels, extending for ∼20 cm, with a maximum thickness of 1.6 cm from T12 to L1. Results: Within 12 h, emergency decompressive laminectomy from T10 to L1 was performed, and evacuation of the hematoma was achieved. The postoperative course and neurological recovery of the patient were optimal. After discharge, the patient continued the rehabilitative treatment started during hospitalization, achieving an excellent functional outcome in 1 month. Conclusions: Spinal epidural hematoma (SEH) is a rare clinical finding that can occur following trauma or spontaneously (SSEH). We describe, to the best of our knowledge, the second most extensive idiopathic SSEH and the longest with involvement of the dorsolumbar spine that had a excellent functional outcome due to emergency decompressive laminectomy, which is emphasized in the treatment of these rare pathologies.