Interrelation of cognitive functions and neural networks with blood flow velocity through the internal jugular vein in patients with chronic cerebral ischemia

Understanding age-related and functional changes in cerebral venous circulation is critical for the development of new preventive, diagnostic and therapeutic approaches to maintaining brain health in the elderly. Chronic cerebral ischemia is one of the widespread socially significant vascular diseases caused by a decrease in the level of blood circulation. To assess the role of venous outflow through the internal jugular veins in cognitive decline and neural networks in patients with chronic cerebral ischemia, 30 men and 40 women (average age 66.5 years), cognitive functions and organization of neural networks were studied at high and low levels of cerebral venous blood flow through the internal jugular veins. To assess the venous outflow, the systolic blood flow rate was measured by the internal jugular veins. A higher rate of venous outflow through internal jugular veins is associated with a more successful performance of the Luria test for verbal memory. A higher or lower blood flow rate affects the formation of neural networks of the brain. At a higher blood flow rate, the predominant areas of the resting neural networks (the passive mode network of the brain and the salient network) are localized in the frontal regions, at a low blood flow rate, the predominant neural network (frontal-parietal) is located in the left hemisphere. The state of faster and slower venous outflow forms neural networks using different neural formations that affect verbal memory. Reorganization of neural networks in this case, apparently, is the central mechanism responsible for cognitive decline in chronic cerebral ischemia (2 figs, 1 table, bibliography: 10 refs)

The impact of spontaneous echo contrast on tunneled dialysis catheter patency

Background: Spontaneous echo contrast (SEC) is an ultrasonographic image of swirling blood flow resembling a dynamic, cigarette smoke-like image. It is mostly observed during the insertion of tunneled dialysis catheters (TDC) into internal jugular veins with ultrasound guidance, often different levels of SEC can be seen. The aim of this study is to investigate the impact of SEC detected during TDC insertion on the patency of the catheter. Methods: Patients who had a TDC insertion in our clinic between January 2015 and December 2020 were prospectively evaluated. The patients were grouped into five groups according to the sec level and followed. Results: A total of 226 patients were examined, among which 107 were male (47.3%). The mean age of all patients was 63.1 ± 9.5 years. SEC grade and catheter occlusion was evaluated, it was observed that higher SEC grades were correlated with faster catheter thrombosis postinsertion. During the follow-up period, it was found that, compared to the SEC 0 group, catheter thrombosis occurred 3.22 times faster in the SEC 1 group, 2.66 times faster in the SEC 2 group, 5.80 times faster in the SEC 3 group, and 26.33 times faster in the SEC 4 group. (HR: 3.22, 2.66, 5.80, 26.33, respectively). Hematological parameters were evaluated by regression analysis, it was observed that hemoglobin, fibrinogen, and platelet count were not risk factors for SEC formation and SEC grade. Conclusion: Significant relationship was found between SEC grade detected during catheter insertion and catheter thrombosis in patients undergoing hemodialysis with a TDC.

Communicating vein between the right external and internal jugular veins: a case report

The external jugular vein is a superficial vein that has a relatively diagonal to vertical course in the neck region and runs superficial to the sternocleidomastoid muscle. This vein is formed by the union of the posterior division of the retromandibular vein with the posterior auricular vein and it is responsible for draining most of the scalp and face as well. Sound knowledge of variations of the external jugular veins and the internal jugular veins, is important as these veins are used or targeted in specific medical procedures such as external jugular vein cannulation or radical neck dissection, respectively. During routine postgraduate dissection of the neck region in a 58-year-old female cadaver, the right external jugular vein was seen communicating with the right internal jugular vein via a communicating vein. The communicating vein was located approximately at the lower border of the thyroid cartilage and the upper border of the cricoid cartilage. A thorough understanding of anatomical variations is important in various medical disciplines and more specifically to anatomists, radiologists, and surgeons. This case report does not solely aim to increase awareness regarding variations of the jugular veins that can be possibly encountered during a neck endovascular procedure, but also contribute to the identification of the prevalence rate of this variation.

Cerebral venous sinus thrombosis due to external compression of internal jugular vein

Cerebral venous sinus thrombosis (CVST) is a special subtype of stroke that may be life-threatening in severe cases. CVST has distinct risk factors and is frequently overlooked because of its initially nonspecific clinical presentation. We herein describe a 72-year-old man who developed CVST in the right lateral sinus. Despite the absence of common risk factors in this patient, he developed external compression of the bilateral internal jugular veins by a lateral mass of the C1 vertebra and expansion of the carotid artery. Because of his elevated D-dimer and fibrinogen concentrations, which are associated with ongoing activation of the coagulation system, the patient underwent treatment with batroxobin combined with anticoagulation. Recanalization of the sinus was achieved, and his high intracranial pressure and papilledema remarkably decreased. We conclude that external compression of the internal jugular veins, which can be identified with three-dimensional computed tomography venography, may be an important risk factor for CVST.

Numerical modeling of blood flow in the internal jugular vein with the use of computational fluid mechanics software

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.