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Objectives: This study was aimed at evaluation of the diagnostic value of Doppler sonography for the assessment of abnormalities in the internal jugular veins (IJVs). Method: One hundred and sixteen IJVs were assessed in 58 patients with associated multiple sclerosis. Findings of Doppler sonography were compared with results of the reference test: catheter venography. Results: At least one positive extracranial sonographic criterion suggesting venous abnormality was found in 92.2% of the assessed veins. Yet, sensitivity, specificity, positive and negative predictive values of sonography were low: 93.4%, 12.0%, 79.4% and 33.3% for at least one positive criterion, and for at least two positive criteria: 29.3%, 75.0%, 81.8% and 21.7%, respectively. Conclusions: Our research has shown that currently used extracranial sonographic criteria for the detection of obstructive venous abnormalities in the IJVs are of limited diagnostic value. For the time being, diagnosis of this vascular pathology should be given using catheter venography. [ABSTRACT FROM AUTHOR]

Wstęp: Okołoroczne fluktuacje częstości zachorowań obserwuje się w wielu schorzeniach naczyniowych. W klimacie typowym dla Polski schorzenia związane z zakrzepicą (m.in. zawał serca, udar mózgowy, żylna choroba zakrzepowoatorowa, zakrzepica tętnic obwodowych) mają szczyt zachorowań w okresie zimowym, podczas gdy objawy kliniczne przewlekłej niewydolności żylnej i związane z nimi: liczba wizyt w poradniach i spożycie leków są najbardziej nasilone latem. Celem pracy było określenie okołorocznej chronobiologii żylnych owrzodzeń podudzi. Materiał i metody: Dokonano przeglądu dokumentacji medycznej 297 chorych leczonych z powodu żylnych owrzodzeń podudzi w okresie od stycznia 2000 roku do grudnia 2005 roku. Ponieważ dane uzyskane od chorych z długim wywiadem chorobowym mogły być mało wiarygodne, w analizie uwzględniono tylko owrzodzenia (213 przypadków) z wywiadem do 12 miesięcy. Oceniono, w którym miesiącu powstało owrzodzenie jak również, czy wyniki późniejszego leczenia miały związek z porą roku, w jakiej otwarło się owrzodzenie. Wyniki: Stwierdzono, że owrzodzenia najczęściej tworzyły się wiosną i jesienią, natomiast owrzodzenia, które otwarły się w tych porach roku goiły się szybciej w porównaniu z owrzodzeniami powstałymi w okresie letnim lub zimowym. Wnioski: Uzyskane dane mogą wskazywać, że chociaż tzw. żylne owrzodzenia mają związek z patologiczną hemodynamiką w układzie żylnym kończyny, to jednak czynnik wyzwalający owrzodzenia prawdopodobnie nie jest bezpośrednio związany z układem naczyniowym. Fluktuacje częstości występowania owrzodzeń żylnych są podobne do chronobiologii choroby wrzodowej. Być może etiopatogeneza tych dwóch jednostek chorobowych, w których dochodzi do uszkodzeń tkanki nabłonkowej, ma pewne cechy wspólne. Można spekulować, że owrzodzenia żylne podudzi są wyzwalane albo przez dotąd niepoznany drobnoustrój (jak Helicobacter pylori w przypadku choroby wrzodowej) lub też owrzodzenie jest wyzwalane przez podobny czynnik molekularny (np. przez którąś z cytokin prozapalnych). Nie jest jasne, czy stwierdzone równocześnie korelacje między okresem powstania owrzodzenia a wynikami leczenia są związane z czynnikiem odpowiedzialnym za tworzenie się owrzodzenia, czy też są to dwa odrębne zjawiska. [ABSTRACT FROM AUTHOR]

Aim: Diastasis recti is a common contour abnormality of the anterior abdominal wall, where an increased distance between the rectus abdominis muscles results in a visible or palpable bulge in this area. This study aimed to characterize this clinical entity in children., Material and Methods: Anatomy of the rectus abdominis muscles and the linea alba, with a special focus on the interrectus distance (distance between two bellies of the rectus abdominis muscles), was studied using ultrasound. Anthropometric and ultrasonographic assessments were performed on 38 children aged 7-12 years. According to the clinical definition of bulging in the epigastrium, diastasis was diagnosed in 12 children (31.6%), significantly more often in boys than in girls (50.0% vs. 6.3%). Other clinical and anthropometric variables, such as age, history of preterm birth, body mass, body mass index, waist circumference, and height, were not significantly associated with diastasis recti., Results: Diastasis recti, defined by the ultrasonographic criterion of interrectus distance >20 mm, was found in 10 children (26.3%), with no significant differences between boys and girls. Still, there was a moderate agreement between these two modes of diagnosing diastasis: the Cohen's kappa coefficient was 0.49. This suggests that ultrasonographic measurement of the interrectus distance should not be considered an alternative and more precise method of diagnosing diastasis., Conclusions: Our study indicates that diastasis recti is quite common in the pediatric population, especially among boys. However, more studies are needed in children to understand the functional relevance and natural course of this clinical entity., Competing Interests: Conflict of interest The authors do not report any financial or personal connections with other persons or organizations which might negatively affect the contents of this publication and/or claim authorship rights to this publication., (© 2024 Agata Maria Kawalec-Rutkowska et al., published by Sciendo.)

With the expansion of wireless mobile networks into both the daily lives of individuals as well as into the widely developing market of connected devices, communication is an increasingly attractive target for attackers. As the complexity of mobile cellular systems grows and the respective countermeasures are implemented to secure data transmissions, the attacks have become increasingly sophisticated on the one hand, but at the same time the system complexity can open up expanded opportunities for security and privacy breaches. After an in-depth summary of possible entry points to attacks to mobile networks, this paper first briefly reviews the basic principles of the physical layer implementation of 4G/5G systems, then gives an overview of possible attacks from a physical layer perspective. It also provides an overview of the software frameworks and hardware tool-software defined radios currently in use for experimenting with 4G/5G mobile networks, and it discusses their basic capabilities. In the final part, the paper summarizes the currently most promising families of techniques to detect illegitimate base stations-the machine-learning-based, localization-based, and behavior-based methods.

Competing Interests: The authors declare no conflict of interest.

Objectives: The optimal treatment strategy for ischemic stroke in patients presenting with tandem occlusions of the internal carotid artery remains controversial. Several studies have demonstrated better clinical outcomes after eptifibatide, which is a short half-life antiplatelet agent. This retrospective analysis focused on the safety and efficacy of low-dose eptifibatide administration in stroke patients with tandem lesions., Methods: We evaluated the results of endovascular treatment in 148 stroke patients with tandem lesions. Patients in whom balloon angioplasty alone resulted in satisfactory cerebral flow did not receive eptifibatide (33 patients); others received this drug together with stent implantation (115 patients). Eptifibatide was given as an intravenous bolus of 180 μg/kg and then in a modified low dose of 1 μg/kg/min for 24 hours., Results: There were no statistically significant differences between both groups regarding 30-day mortality, frequency of thrombotic events, or hemorrhagic complications. An analysis of clinical status at 30-day follow-up revealed that the administration of eptifibatide was associated with a statistically significant better outcome: a higher rate of either no neurological symptoms or only mild symptoms (4 NIHSS points maximally)., Conclusions: The administration of eptifibatide in stroke patients presenting with tandem lesions is relatively safe. Moreover, treatment with this drug can improve clinical outcomes in these challenging patients.

The clinical relevance of nozzle-like strictures in upper parts of the internal jugular veins remains unclear. This study was aimed at understanding flow disturbances caused by such stenoses. Computational fluid dynamics software, COMSOL Multiphysics, was used. Two-dimensional computational domain involved stenosis at the beginning of modeled veins, and a flexible valve downstream. The material of the venous valve was considered to be hyperelastic. In the vein models with symmetric 2-leaflets valve without upstream stenosis or with minor 30% stenosis, the flow was undisturbed. In the case of major 60% and 75% upstream stenosis, centerline velocity was positioned asymmetrically, and areas of reverse flow and flow separation developed. In the 2-leaflet models with major stenosis, vortices evoking flow asymmetry were present for the entire course of the model, while the valve leaflets were distorted by asymmetric flow. Our computational fluid dynamics modeling suggests that an impaired outflow from the brain through the internal jugular veins is likely to be primarily caused by pathological strictures in their upper parts. In addition, the jugular valve pathology can be exacerbated by strictures located in the upper segments of these veins.

In March and April 2021 several countries temporarily suspended vaccinations with adenoviral vector-based COVID-19 vaccines. Concerns of national regulators particularly regarded very rare cases of cerebral venous sinus thrombosis after immunization with this type of vaccine. Until now, these adverse events were interpreted as standard hypercoagulable events, but their clinical characteristics suggest that they may actually represent unique thrombotic disorders referred to as immunothrombosis. In this paper it is speculated that it is possible that immunothrombosis after this type of vaccine results from formation of neutrophil extracellular traps (NETs) in veins affected by stagnant blood flow. Such a stasis occurs in individuals with anatomical variants of cerebral venous outflow, which may explain why these events are primarily seen in the cerebral veins. It has already been found that SARS-CoV-2 spike protein can evoke release of NETs. There is also a question if thrombotic events after adenoviral vector-based COVID-19 vaccines could be avoided. These vaccines will still be needed to curb COVID-19 worldwide, since they do not require transportation and storage at very low temperatures. Perhaps, vaccinations with these vaccines should be performed in combination with prophylactic administration of dipyridamole, which is an inexpensive pharmaceutical agent reducing the release of NETs., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier España, S.L.U.)

Competing Interests: The authors declare no conflict of interest.

Some of the COVID-19 patients present with ischemic lesions of their finger and toes. Standard anticoagulant therapy is usually unsuccessful for the treatment of this unique presentation of COVID-19. In this review current evidence is presented, which supports the hypothesis that these necrotic lesions are primarily related to the formation of neutrophil extracellular traps is blood vessels. Also, currently available and potential pharmacological methods of the management of this unique thrombotic complication are discussed. Drugs that possibly could be used in COVID-19 patients suffering from acute ischemia of distal parts of the extremities particularly comprise DNase I and DNase1L3, which could directly dissolve these extracellular webs that are mostly composed of DNA. However, at the moment, none of these enzymes are registered for an intravascular administration in humans. Lactoferrin and dipyridamole are other pharmaceutical agents that could potentially be used for the treatment of neutrophil extracellular traps-evoked digital ischemia. These agents exhibit prophylactic activity against excessive formation of these extracellular structures. Such an experimental treatment should probably be accompanied by standard antithrombotic management with heparin. Open-label and then randomized trials are needed to confirm feasibility, safety and efficacy of the above-suggested management of critically ill COVID-19 patients., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Competing Interests: The authors declare no conflict of interest.

Objectives: To determine the site and nature of altered hemodynamics in pathological internal jugular veins., Method: With the use of computational fluid mechanics software we simulated blood flow in 3 D models of the internal jugular veins that exhibited different morphologies, including nozzle-like strictures in their upper parts and valves in the lower parts., Results: In a majority of models with nozzle-like strictures, especially those positioned asymmetrically, abnormal flow pattern was revealed, with significant flow separation and regions with reversed flow. Abnormal valves had no significant impact on flow in a case of already altered flow evoked by stricture in upper part of the vein., Conclusions: In our jugular model, cranially-located stenoses, which in clinical practice are primarily caused by external compression, cause more significant outflow impact respect to endoluminal defects and pathological valves located more caudally.

Objectives: Little is known how calibre and length of needles affect the stability of sclerosing foam., Methods: Foams were made of 0.5%, 1%, 2% and 3% polidocanol, and 0.2%, 0.5%, 1% and 3% sodium tetradecyl sulfate (STS), which were mixed with air in the proportion of 4:1. These foams were ejected through needles with the length of: 4 mm, 6 mm and 13 mm, and diameter of: 0.26 mm, 0.3 mm and 0.4 mm., Results: Foams made of more concentrated polidocanol were more stable. Regarding STS an opposite relationship was revealed. Foams made of polidocanol were more stable if ejected through a longer needle, while the length of needle did not significantly affect stability of STS foams. Foams ejected through 0.26 mm diameter needles were very unstable. In the case of 0.5% polidocanol, 0.3x6mm needle provided atypically stable foam., Conclusion: In order to inject maximally stable foam, calibre and length of needle should be taken into account.

Introduction: Although filters are still preferred during carotid stenting, proximal protection systems (PPS) are increasingly used during these procedures. PPS seem to be safer than distal systems, especially in symptomatic patients, but evidence supporting their use is limited., Aim: This was a post hoc survey with 30-day mid-term and long-term follow up, which was aimed at assessment of the safety and efficacy of stenting of the internal carotid artery under PPS in symptomatic patients., Material and Methods: We analysed the results of stenting in 120 symptomatic patients presenting with at least 60% stenosis. Patients were aged 67.9 ±9.8 years, and 12 patients were older than 80 years. An occlusion of contralateral artery was found in 5 patients and bilateral stenosis in 26 patients. The primary endpoint of this study was the proportion of patients who had new neurological events, including transient ischemic attack and minor or major stroke in 30-day follow-up. The secondary endpoint was a composite of technical and clinical success. During long-term follow-up we assessed new neurological events and stenoses of implanted stents., Results: The incidence of new neurological events during 30-day follow-up was 0.8%. The rate of technical success defined by secondary endpoint was 100%. Mean internal carotid artery stenosis before and after stent implantation was 93.8 ±9% and 8.4 ±6.3%, respectively (p < 0.001). Procedural success was achieved in all cases. During long-term follow-up there were two (1.7%) asymptomatic in-stent stenoses and no (0%) new neurological events., Conclusions: Endovascular management of symptomatic carotid stenosis under PPS is safe, feasible, and appears to be a good alternative to surgical endarterectomy., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2020 Fundacja Videochirurgii.)

Recently intriguing results of the research performed on astronauts of the International Space Station have been published. Unexpectedly, in some crew members a stagnant and bidirectional flow in the internal jugular vein was found, and in one of the astronauts this vein seemed to be totally thrombosed. If it actually were the case that in the settings of weightlessness there is a substantial risk of jugular vein thrombosis, any long-term human space missions would be extremely dangerous. Yet, we interpret these findings differently. In our opinion, what has been explained as bidirectional flow, actually represented the flow separation, and what has been described as occluded vein was rather the vein with recirculating and low-velocity flow. In this paper, basing on physical laws governing the flow of fluids, we describe how the flow separation and recirculation can develop in a dilated internal jugular vein, how it can affect cerebral outflow through this vein, why such a phenomenon is more likely in the settings of microgravity and how future research on this topic should be directed., (Copyright © 2020 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.)

Introduction: Mechanical thrombectomy is an alternative to local thrombolysis for the treatment of severe ischaemia in the femoropopliteal segment, but stent implantation is usually required after this procedure. The use of drug-eluting balloons (DEBs) may overcome long-term problems associated with stents, but it remains unclear how often such a treatment is technically feasible and efficient., Aim: This post hoc single-centre study was aimed at assessment of the feasibility, safety and efficacy of mechanical thrombectomy followed by application of DEBs., Material and Methods: Fifty-one patients, aged 69.1 ±11.6 years, were managed for acute thrombotic or chronic critical ischaemia in the femoropopliteal segment using the Rotarex device. Following mechanical thrombectomy, on condition that there was no significant residual stenosis or dissection, lesions were managed with paclitaxel-coated DEBs, which was a desired strategy (24 patients). The remaining 25 patients underwent stent implantations, which was regarded as bailout treatment. Final follow-up was scheduled 12 months after the procedure., Results: The primary-assisted patency rate after mechanical rotational thrombectomy with additional balloon angioplasty and/or stenting was 97.1% (49 patients). The early mortality rate was 2.0% (1 patient) and the amputation rate was 4.1% (2 patients). There were no late mortalities or limb amputations at 12-month follow-up, but significant restenoses occurred in 13 (27.1%) patients. These restenoses were more frequent in patients who underwent stent implantation (45.5%) than those managed with DEBs (12.5%), and in patients managed for secondary lesions., Conclusions: In selected patients mechanical rotational thrombectomy in the femoropopliteal segment followed by application of DEB is a safe, effective and long-lasting method of revascularisation., Competing Interests: The authors declare no conflict of interest.

Introduction: Symptomatic dissections (SD) of cervical arteries are still a therapeutic problem. Although endovascular management (EM) is currently a preferred method of treatment of SD, complications associated with this method of treatment in published reports are quite frequent (3-16%)., Aim: In this retrospective study we analyzed the results of EM with novel, double-mesh stent and protection systems (PS) for SD of the internal carotid (IC) or vertebral arteries (VA) that coexisted with hemodynamically significant stenosis or aneurysmatic dilatation of the dissected artery., Material and Methods: We evaluated the results of EM in 19 patients (men 15, median age: 55, range: 25-83), presenting with SD of the IC or VA with coexisting stenosis and/or aneurysmatic dilatation of the artery in segments C1-C5 of IC or V0-V4 of VA. Twelve patients had a stroke, 6 TIA, and 3 patients a headache and/or a neck pain with Horner syndrome. Stents and PS were tailored according to the location, length of dissection and coexisting stenotic or aneurysmatic lesions., Results: There were no new strokes, in-hospital deaths or other serious morbidities during the procedure and postprocedural hospital stay. There were no fatalities during 6-40 months of follow-up. In control angiographies performed after interventions all patients demonstrated a patent target artery, complete coverage of the dissection and aneurysm by stents and no new lesions in the area of the previous dissection., Conclusions: The results of this study indicate that EM of SD of IC and VA with the new stents and PS is safe and effective with good early and midterm results., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2019 Termedia Sp. z o. o.)

About 10 years ago, the so-called chronic cerebrospinal venous insufficiency syndrome was discovered. This clinical entity, which is associated with extracranial venous abnormalities that impair venous outflow from the brain, was initially found exclusively in multiple sclerosis patients. Currently, we know that such venous lesions can also be revealed in other neurological pathologies, including Alzheimer's and Parkinson's diseases. Although direct causative role of chronic cerebrospinal venous insufficiency in these neurological diseases still remains elusive, in this paper, we suggest that perhaps an abnormal venous drainage of the brain affects functioning of the glymphatic system, which in turn results in the accumulation of pathological proteins in the cerebral tissue (such as β-synuclein, β-amyloid and α-synuclein) and triggers the venous outflow from the cranial cavity and circulation of the cerebrospinal fluid in the settings of neurodegenerative disease., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In this article, we suggest that the glymphatic system of the brain can play an important role in the pathogenesis of high-altitude cerebral edema (HACE). Water enters the intercellular space of the brain primarily through aquaporin-4 (AQP-4) water channels, the main component of the glymphatic system, whereas acetazolamide, pharmacological agent used in the prevention of HACE, is the blocker of the AQP-4 molecule. In animal experiments, cerebral edema caused by hypobaric hypoxia was associated with an increased expression of AQP-4 by astrocytes. Also, the glymphatic system is primarily active during sleep, although sleep at high altitude is a well-known risk factor of developing HACE. All these findings support our hypothesis. We suggest that future research on the prevention and treatment of HACE should involve factors that are already known to modify activity of the glymphatic system, such as angiotensin-converting enzyme inhibitors or other pharmaceutical agents affecting noradrenergic system of the brain, body posture during sleep, anatomy of the veins draining the cranial cavity, and the influence of physical activity before and during exposure to high altitude, especially in relation to sleep.

Introduction: Intravenous thrombolysis is the treatment of choice in patients presenting with high- and intermediate-risk pulmonary embolism. The role of percutaneous mechanical pulmonary thrombectomy (PMPT) is not fully established, although selected patients can be managed with this method., Aim: This open-label single-centre prospective pilot study was aimed at assessing the feasibility of PMPT for the treatment of severe pulmonary embolism in a Polish hospital. We also evaluated the safety and efficacy of such management., Material and Methods: We managed 7 patients, aged 52.7 ±16.6 years, presenting with high- and intermediate-risk pulmonary embolism (4 patients with class 5 and one patient with class 4 of the Pulmonary Embolism Severity Index), with occlusion of at least 2 lobar arteries and contraindications for thrombolysis. Percutaneous mechanical pulmonary thrombectomy was performed using the AngioJet system., Results: It was possible to introduce the thrombectomy system to the pulmonary arteries in all patients. The procedure was successful in 6 patients (technical success rate: 85.7%). Two (28.6%) patients died during the hospital stay, one patient with unsuccessful thrombectomy and the other due to pneumonia. In all survivors control echocardiography demonstrated normalised function of the right ventricle. Also, dyspnoea disappeared and blood gas parameters normalised. There was no recurrent thromboembolism during 3-14 months of follow-up., Conclusions: In the Polish setting, in selected patients, management of high- and intermediate-risk pulmonary embolism with PMPT is technically feasible. Such treatment is relatively safe and effective. It can be an alternative to standard management, especially in patients with contraindications for fibrinolysis or surgical embolectomy.

Background: Although surgical endarterectomy remains the treatment of choice for carotid artery stenosis, carotid artery stenting (CAS) with use of proximal protection systems (PPS) plays an very important role as alternative treatment modality, especially in patients with critical, symptomatic lesions. This study was single-centre study to evaluate the technical and clinical success of proximal protection devices as the first choice for embolic protection in symptomatic and asymptomatic carotid stenosis in patients with bilateral, advanced lesions of carotid arteries (bilateral stenoses or stenosis and occlusion)., Methods: This was a post hoc analysis, with 30-day follow up. We analyzed results of treatment of 38 patients who underwent 38 CAS with PPS, 17 such procedures in asymptomatic (group A), and 21 in symptomatic individuals (group B). The GORE ® Flow Reversal System (W.L. Gore, Flagstaff, AZ, USA) was used in 2 patients, and the Mo.Ma Ultra device (Medtronic, Minneapolis, MN, USA) in 36 patients. Mean age was 68±7 years, 65% percent of patient were male., Results: There were no procedural and during 30-day follow-up neurologic events. Intolerance of occlusion system occurred in 4 patients (11%) in both groups with any later symptoms. Risk factors of this adverse event comprised: lesions of the left internal carotid lesion and coexisiting diabetes mellitus., Conclusions: CAS in high risk patients with bilateral lesions of carotid arteries with the use of PPS seems to be a relatively very safe procedure., (Copyright © 2017. Published by Elsevier Urban & Partner Sp. z o.o.)