Nervous Structures Research Articles

Analysis of the Curative Effect of Diffusion Tensor Imaging-Guided Percutaneous Endoscopic Lumbar Discectomy

Diffusion tensor imaging (DTI), a novel method of describing nerve structure, is a special form of magnetic resonance imaging (MRI). This new imaging method can be used to locate the diseased nerve roots in lumbar disc herniation. The objective of this study is to compare patient outcomes between single-level and doublesection percutaneous endoscopic lumbar discectomy (PELD) in the treatment of lumbar intervertebral disc herniation with single nerve root compression, where single-sided PELD is guided by magnetic resonance diffusion tensor imaging (DTI). The clinical data of patients with lumbar intervertebral disc herniation with double compression of single nerve root symptoms in the Affiliated Hospital of Weifang Medical University from January 2019 to May 2021 were retrospectively summarized and divided into single-level percutaneous endoscopic discectomy (PELD) group after DTI localization and double-section PELD group. The operation time, intraoperative bleeding, VAS score and JOA score of the two groups were compared, as well as the preoperative and postoperative fractional anisotropy (FA) values in the DTI group. The operation time and intraoperative bleeding volume of patients in the DTI group were significantly lower than those in the double segment group, and there was no significant difference between VAS scores and JOA scores in the two groups. After the operation, the nerve root FA value of the responsible compression site of patients in the DTI group increased significantly, but it was still lower than the healthy symmetrical part. The single-level PELD based on DTI has achieved a similar effect to that of the doublesegment PELD in 3 months after the operation, which can improve the FA value of the lesion nerve root. Its bleeding amount is less, and the operation time is shorter, but the efficacy of this technology still requires long-term follow-up of large samples.

Nerve Transfers Using a Dedicated Microsurgical Robotic System.

Microsurgical demands in peripheral nerve surgery are increasing. Because of the development of multiple simultaneous selective nerve transfers, the transposition of very small nerves and even single fascicles has evolved. Coaptation of these increasingly smaller structures require high skills in microsurgical techniques. In addition, the surgical situs often has very limited access and is difficult to reach with conventional microsurgical options. Robot technology, the Symani Surgical System (Medical Microinstruments, S.p.A, Calci, Pisa, Italy), was used for epineural coaptation of three donor nerves (intercostal nerves 4-6) to the long thoracic nerve and the thoracodorsal nerve as recipient nerves in a patient with brachial plexus palsy. The coaptations could be carried out successfully with the microsurgical robot technology. In combination with a high-magnification (up to 26×) 3D-exoscope, the epineural sutures could be placed very precisely and accurately. Using this new microsurgical robotic system, successful coaptation of very small nerve structures is possible. This opens possibilities for the microsurgeon to carry out even finer, more targeted and more complex nerve transfers, including procedures in anatomical regions that are difficult to reach.

STRUCTURE OF INTRAMURAL NERVE ELEMENTS OF THE URINARY BLADDER IN PATIENTS WITH DIABETIC CYSTOPATHY

Using histological, and histochemical methods, morphological changes in the intramural nerve elements of the urinary bladder were studied in 6 patients suffering from diabetic cystopathy and who died from various complications of diabetes mellitus. The control group consisted of 4 practically healthy persons who died as a result of a car accident. For histological examination, tissue pieces of the nerve elements of the bladder were fixed with 12% formalin and impregnated according to the method of Bilshchovsky-Gross and Rasskazov. Adrenergic nerve structures were detected by incubation of sections in a 2% solution of glyoxylic acid, and cholinergic elements by the Karnovsky-Roots method. It was revealed that along with degenerative changes, reactive-compensatory processes also occur in the intramural nerve elements of the bladder in diabetic cystopathy. It was found that the activity of mediators in adrenergic and cholinergic structures decreases.

REPRODUCTIVE HORMONE LEVELS IN WOMEN WITH THALASSEMIA

Using histological, and histochemical methods, morphological changes in the intramural nerve elements of the urinary bladder were studied in 6 patients suffering from diabetic cystopathy and who died from various complications of diabetes mellitus. The control group consisted of 4 practically healthy persons who died as a result of a car accident. For histological examination, tissue pieces of the nerve elements of the bladder were fixed with 12% formalin and impregnated according to the method of Bilshchovsky-Gross and Rasskazov. Adrenergic nerve structures were detected by incubation of sections in a 2% solution of glyoxylic acid, and cholinergic elements by the Karnovsky-Roots method. It was revealed that along with degenerative changes, reactive-compensatory processes also occur in the intramural nerve elements of the bladder in diabetic cystopathy. It was found that the activity of mediators in adrenergic and cholinergic structures decreases.

Immediate and short-term effects of eccentric muscle contractions on structural, morphological, mechanical, functional and physiological properties of peripheral nerves: A protocol for a systematic review and meta-analysis.

It is widely acknowledged that eccentric muscle contractions may cause skeletal muscle damage. However, there is little knowledge about the impact of eccentric contractions on non-muscular structures. Animal and human studies revealed that eccentric contractions can also induce immediate and short-term nerve dysfunction. The purpose of this review is to examine whether eccentric muscle contractions induce immediate and short-term effects on structural, morphological, mechanical, functional and physiological properties of peripheral nerves, from both animal and human studies. A systematic review of randomised (RCTs) and non-randomised controlled trials will be conducted. Four electronic databases (i.e., Medline/Pubmed, Science Direct, PEDro and Cochrane) will be searched using predefined search terms to identify relevant studies. Eligible studies have to comprise any type of eccentric contraction of upper or lower limb muscles. Primary outcomes will include measures related to structure, morphology, mechanical, functional and physiological properties of peripheral nerves. Two independent reviewers will assess eligibility, evaluate risk of bias, and extract relevant data. In human studies, the risk of bias will be assessed by the Cochrane Collaboration risk of bias tool (RoB 2.0 tool) for RCTs and by risk of bias in non-randomised studies of interventions (ROBINS-I) for non-randomised controlled trials; while for animal studies, the risk of bias will be assessed using the SYRCLE's RoB tool. A narrative synthesis will be conducted for all included studies. Also, if appropriate, a meta-analysis will be performed, where the effect size of each outcome will be determined by the standardized mean difference as well as the 95% confidence intervals. I2 statistics will be used to assess heterogeneity. For this study, no ethical approval is required. Findings will be disseminated widely through peer-reviewed publication and conference presentations. The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO). Registration number: CRD42021285767.

Ultrasonography in Pain Medicine and Regional Anesthesia Expert Consensus

Ultrasound has revolutionized interventional pain medicine and regional anesthesia. It allows visualization of nervoussystem structures, which are the primary targets in pain management and regional anesthesia procedures. Precise andsafe deposition of local anesthetics around nerve structures is made possible with ultrasound, resulting in rapid regionalanesthesia and modulation of pathological pain signals. In diagnostic and prognostic pain treatments, the precisionof drug administration and deposition of small volumes are crucial. Proper identification of the nerve responsible fortransmitting pathological pain signals is key to achieving the desired effect in neurodestructive procedures such asneurolysis, cryoablation, thermocoagulation, or pulsed neuromodulation. Visualization of structures to avoid, such asblood vessels or parenchymal organs, reduces the risk of adverse events like hematoma or damage to sensitive internalorgans. Real-time needle tracking during procedures shortens the duration and increases precision. Monitoring thespread of the administered therapeutic substance during the procedure enhances the effectiveness and selectivityof the block. When combined with X-ray imaging, using ultrasound reduces procedure time and exposure to X-rayradiation. Furthermore, ultrasound does not expose clinicians and patients to harmful X-ray radiation. Widespreadadoption of ultrasound in imaging nervous system structures during regional anesthesia and interventional painprocedures necessitates the development of new procedural standards.

Assessment of the impact of DIAM interspinal dynamic stabilization on pain in the lumbar spine - the role of physiotherapy

Pain in the LS segment occurs in both young and old people. Stabilization training is gaining more and more supporters in returning to proper functioning. Central stabilization is the ability to maintain the correct body posture during static and dynamic movements. The DIAM system of dynamic interspinal stabilization of the spine is a minimally invasive procedure which, by inserting a silicone implant between the spinous processes, relieves the intervertebral joints, the intervertebral disc and reduces the pressure on the nerve structures. Continuation after the procedure is systematic physiotherapy. The aim of the study was to assess the impact of the implant and individually adjusted stabilization training of the lumbar-pelvic-hip complex in patients after dynamic interspinal stabilization with the DIAM method. The study was conducted on a group of 56 people who underwent a minimally invasive procedure and qualified from the 10th day after the operation. The stabilization training was selected individually for each patient, including the current state of health. The training was conducted once a week for four weeks. The conducted stabilization training of the lumbar-pelvic-hip complex turned out to be an effective method in recovery. There was a significant decrease in pain in the lower part of the spine among the examined patients. There was an improvement in physical activity and activities of daily living based on the Ronald-Morris scale. A decrease in the number of points was noted in all subjects. Fast, post-surgical rehabilitation therapy after using dynamic stabilization - DIAM, turned out to be a helpful method in faster recovery. It is reasonable to introduce early rehabilitation according to the scheme established by us after the DIAM dynamic stabilization procedure, as the period of return to work is reduced.

Robot-Guided Ultrasonography in Surgical Interventions.

The introduction of robotic-guided procedures in surgical techniques has brought an increase in the accuracy and control of resections. Surgery has evolved as a technique since the development of laparoscopy, which has added to the visualisation of the peritoneal cavity from a different perspective. Multi-armed robot associated with real-time intraoperative imaging devices brings important manoeuvrability and dexterity improvements in certain surgical fields. The present study is designed to synthesise the development of imaging techniques with a focus on ultrasonography in robotic surgery in the last ten years regarding abdominal surgical interventions. All studies involved abdominal surgery. Out of the seven studies, two were performed in clinical trials. The other five studies were performed on organs or simulators and attempted to develop a hybrid surgical technique using ultrasonography and robotic surgery. Most studies aim to surgically identify both blood vessels and nerve structures through this combined technique (surgery and imaging). Ultrasonography is often used in minimally invasive surgical techniques. This adds to the visualisation of blood vessels, the correct identification of tumour margins, and the location of surgical instruments in the tissue. The development of ultrasound technology from 2D to 3D and 4D has brought improvements in minimally invasive and robotic surgical techniques, and it should be further studied to bring surgery to a higher level.

Intraoperative neurophysiological monitoring and spinal cord stimulator implantation

IntroductionSpinal cord injury (SCI) is one of the most dreaded complications after spinal cord stimulation (SCS) implantation surgery. As a result, intraoperative neurophysiological monitoring (IONM) has been proposed to avoid...

Pain Management Interventions for the Treatment of Chronic Low Back Pain: A Systematic Review and Meta-Analysis.

Determine the relative effectiveness and safety profiles of percutaneous and minimally invasive interventions for chronic low back pain. A systematic search was performed for randomized controlled trials published in the past 20 years reporting on radiofrequency ablation of the basivertebral, disk annulus and facet nerve structures, steroid injection of the disk, facet joint, and medial branch, biological therapies, and multifidus muscle stimulation. Outcomes evaluated included Visual Analog Scale (VAS) pain scores, Oswestry Disability Index (ODI) scores, quality of life (SF-36 and EQ-5D) scores, and serious adverse event (SAE) rates. Basivertebral nerve (BVN) ablation was chosen as the subject of comparison to all other therapies using a random-effects meta-analysis. Twenty-seven studies were included. BVN ablation was found to provide statistically significant improvements in VAS and ODI scores for 6-, 12- and 24-month follow-up ( P ≤0.05). Biological therapy and multifidus muscle stimulation were the only 2 treatments with both VAS and ODI outcomes not significantly different from BVN ablation at 6-, 12-, and 24-month follow-up. All outcomes found to be statistically significant represented inferior results to those of BVN ablation. Insufficient data precluded meaningful comparisons of SF-36 and EQ-5D scores. The SAE rates for all therapies and all reported time points were not significantly different from BVN ablation except for biological therapy and multifidus muscle stimulation at the 6-month follow-up. BVN ablation, biological therapy, and multifidus stimulation all provide significant, durable improvements in both pain and disability compared with other interventions, which provided only short-term pain relief. Studies on BVN ablation reported no SAEs, a significantly better result than for studies of biological therapy and multifidus stimulation.

ACUTE ENCEPHALOMYELOPOLYRADICULONEUROPATHY THAT OCCURRED AFTER BNT162B2 MRNA VACCINATION AGAINST COVID-19: A CLINICAL CASE REVIEW

SARS-CoV-2 and side effects of SARS-CoV-2 vaccination show tropism to nervous system structures. Neurological side effects from the central and peripheral nervous systems have been observed quite rarely after vaccination against COVID-19 compared to a large number of vaccinated individuals. The article presents a clinical case of simultaneous damage to the central and peripheral nervous systems in the form of acute autoimmune inflammatory encephalomyelopolyradiculoneuropathy, which occurred after receiving the first dose of the BNT162b2 mRNA vaccine. The severe course of encephalomyelopolyradiculoneuropathy with peripheral tetraplegia, sensory disturbances, bulbar syndrome, and dysautonomia, followed by the occurrence of pneumonia, secondary bacterial meningoencephalitis, the need for long-term mechanical ventilation led to the occurrence of pneumothorax and multiple organ failure, which caused the patient’s death after one and a half months of intensive therapy.
 Thus, the acute autoimmune inflammatory encephalomyelopolyradiculoneuropathy can be considered as a probable rare neurological complication of SARS-CoV-2 vaccination with mRNA-based vaccines. Encephalomyelopolyradiculoneuropathy can have a severe course, accompanied by multiple complications and leading to death. Establishing of the causal relationships of the occurrence of rare neurological pathological conditions close in time to vaccination against SARS-CoV-2 with mRNA-based vaccines requires additional further researches.

Ultrasound diagnostics in the assessment of traumatic peripheral nerve damage in combat trauma

BACKGROUND: Traumatic peripheral nerve damage is a significant clinical and social problem, which is characterized by a high level of disability in young patients.
 AIM: To assess the diagnostic efficiency of ultrasound in the diagnosis of peripheral nerve damage in combat trauma.
 METHODS: A total of 163 patients (362 peripheral nerves) were examined. The duration of traumatic nerve damage was 2273 days. All patients were men aged 2048 years. Ultrasound was performed with 717 MHz linear transducers on an ACUSSON S2000 device using standard technique in B-mode, in longitudinal and transverse scanning planes, with the use of Doppler techniques. Statistical analysis was conducted to assess diagnostic efficiency. Calculation of operational (sensitivity and specificity) and integral (accuracy) characteristics was performed by the qualitative assessment of the reference method (surgical intervention) and the method under study (ultrasound).
 RESULTS: Peripheral nerve damage resulted from combat trauma. In 120 (73.6%) cases, injuries of the limbs were accompanied by injuries of the osteoarticular apparatus and vessels. A total of 274 (75.7%) nerves had signs of traumatic damage. Multiple nerve injuries were observed in 95 (58.3%) people. Nerves of the upper extremities were damaged more frequently (185 [67.5%]) compared to nerves of the lower extremities (89 [32.5%]). Contusional structural changes were observed in 181 (66%) nerves. Impairment of anatomical integrity was diagnosed in 46 (16.8%) nerves, while complete impairment was found in 29 (10.6%) cases with the presence of diastasis between the nerve ends. Early after injury, a wound canal and hematomas were visualized near the nerve. In 4 cases, a foreign body of metallic density was visualized in the nerve sheath. After 3 weeks from the moment of injury, terminal neuromas were observed. The neuroma sizes for the proximal and distal ends were 0.50.3 to 1.60.6 cm and 0.40.2 to 1.30.6 cm (avascular), respectively. Adjacent sections of the nerve over 35 cm were thickened and characterized by echo structure, however, with thickening of all fasciculi and blood flow observed along the periphery of the nerve. Marginal nerve damage was observed in 17 (6.2%) people. In case of marginal neuroma, a significant nerve thickening of 1.43.2 times over a short distance (from 0.4 cm to 1.5 cm) with loss of bundle differentiation of the part of the nerve, pronounced decrease in echogenicity, and absence of Doppler signal was detected. Nerve compression in 47 cases (17.1%) was accompanied by 1.22.3 times thickening of nerve trunks, indistinct contours, decreased echogenicity, and significant changes in the nerve structure. Compression was due to cicatricial changes, hematomas, foreign bodies, bone fragments, and in 2 cases spokes from external fixation devices. A total of 106 patients underwent surgery.
 CONCLUSIONS: The ultrasound sensitivity and specificity were 96% and 67%, respectively. The peculiarities of the examination included extensive soft tissue defects and external fixation devices, which significantly complicated the examination. The diagnostic accuracy was 91%. A pronounced cicatricial process (70%) was the main cause of false-positive (6.6%) and false-negative (2.8%) results.

Automated Glaucoma Screening and Diagnosis Based on Retinal Fundus Images Using Deep Learning Approaches: A Comprehensive Review.

Glaucoma is a chronic eye disease that may lead to permanent vision loss if it is not diagnosed and treated at an early stage. The disease originates from an irregular behavior in the drainage flow of the eye that eventually leads to an increase in intraocular pressure, which in the severe stage of the disease deteriorates the optic nerve head and leads to vision loss. Medical follow-ups to observe the retinal area are needed periodically by ophthalmologists, who require an extensive degree of skill and experience to interpret the results appropriately. To improve on this issue, algorithms based on deep learning techniques have been designed to screen and diagnose glaucoma based on retinal fundus image input and to analyze images of the optic nerve and retinal structures. Therefore, the objective of this paper is to provide a systematic analysis of 52 state-of-the-art relevant studies on the screening and diagnosis of glaucoma, which include a particular dataset used in the development of the algorithms, performance metrics, and modalities employed in each article. Furthermore, this review analyzes and evaluates the used methods and compares their strengths and weaknesses in an organized manner. It also explored a wide range of diagnostic procedures, such as image pre-processing, localization, classification, and segmentation. In conclusion, automated glaucoma diagnosis has shown considerable promise when deep learning algorithms are applied. Such algorithms could increase the accuracy and efficiency of glaucoma diagnosis in a better and faster manner.

492-P: Utility of Measures of Nerve Fiber Function and Structure for the Diagnosis of Diabetic Peripheral Neuropathy

Introduction: Identifying diabetic neuropathy (DPN) in the clinic is challenging. The purpose of this study is to investigate the utility of various diagnostic tools for the detection of DPN Methods: The following measures were assessed in controls and patients with type 2 diabetes with and without DPN: clinical neuropathy scores, quantitative sensory testing, corneal confocal microscopy, and sudomotor function. Receiver operating characteristics and areas under the curve with sensitivity and specificity were calculated Results: See Table and Figure Conclusions: Functional measures were more sensitive but less specific than structural ones. Similar to other studies, our study shows that no individual test is reliable per-se. Future studies are needed to investigate the best combination of tests for assessing DPN. Disclosure C.M.Casellini: None. H.Parson: None. C.Cushman: None. A.M.Ingram: None. J.L.Pettaway: None. T.Sears: None. E.S.Siraj: Research Support; Novo Nordisk, Speaker's Bureau; Novo Nordisk, Boehringer Ingelheim and Eli Lilly Alliance.

Effect of Subliminal Auditory Stimulation on Components of Auditory Late Responses and Functional Magnetic Resonance Imaging Data in Adults with Normal Hearing

Background and Aim: The use of subliminal stimulation for unconscious effects on the target population is of great importance. while several studies have generated proper visual and auditory stimuli for subliminal stimulation, no study was found on the long-term effects of it. Therefore, this study aims to investigate the long-term effects of auditory subliminal presentation on the central nervous system structures using fMRI and Auditory Late Responses (ALRs). Methods: Participants were 26 students with a mean age of 24.03±2.32 years. There was four group in study. First, fMRI was done and ALRs were recorded for all of them. Then, music files containing words embedded in them was presented subliminally to participants in groups A and B for 10 days, group C received music file without any subliminal stimuli and group D was control group. It was repeated after 10 days. Results: The subliminal stimuli had significant effects on the amplitudes of P1, N1, P2, and P3 waves (F3=25.03, 25.41, 39.11, and 14.60; p<0.001). Between-group comparison showed significant changes in groups A and B compared to groups C and D (p<0.05). The difference in the recorded potential mean values showed the highest change for recording electrodes in the prefrontal, frontal, and central regions and the lowest change in parietal and occipital regions. There was no significant change for a latency component. Conclusion: Subliminal stimuli, presented appropriately and continuously, can leave long- term effects on the central nervous system structure causing extensive changes in the people’s attitude to a certain subject. Keywords: Subliminal perception; unconscious perception; unconsciousness; subconsciousness; subliminal auditory stimulus

Learning the Biochemical Basis of Axonal Guidance: Using Caenorhabditis elegans as a Model.

Experimental models are a powerful aid in visualizing molecular phenomena. This work reports how the worm Caenorhabditis elegans (C. elegans) can be effectively explored for students to learn how molecular cues dramatically condition axonal guidance and define nervous system structure and behavior at the organism level. Summary of work: A loosely oriented observational activity preceded detailed discussions on molecules implied in axonal migration. C. elegans mutants were used to introduce second-year medical students to the deleterious effects of gene malfunctioning in neuron response to extracellular biochemical cues and to establish links between molecular function, nervous system structure, and animal behavior. Students observed C. elegans cultures and associated animal behavior alterations with the lack of function of specific axon guidance molecules (the soluble cue netrin/UNC-6 or two receptors, DCC/UNC-40 and UNC-5H). Microscopical observations of these strains, in combination with pan-neuronal GFP expression, allowed optimal visualization of severely affected neurons. Once the list of mutated genes in each strain was displayed, students could also relate abnormal patterns in axon migration/ventral and dorsal nerve cord neuron formation in C. elegans with mutated molecular components homologous to those in humans. Students rated the importance and effectiveness of the activity very highly. Ninety-three percent found it helpful to grasp human axonal migration, and all students were surprised with the power of the model in helping to visualize the phenomenon.

The neuroscience of cancer.

The nervous system regulates tissue stem and precursor populations throughout life. Parallel to roles in development, the nervous system is emerging as a critical regulator of cancer, from oncogenesis to malignant growth and metastatic spread. Various preclinical models in a range of malignancies have demonstrated that nervous system activity can control cancer initiation and powerfully influence cancer progression and metastasis. Just as the nervous system can regulate cancer progression, cancer also remodels and hijacks nervous system structure and function. Interactions between the nervous system and cancer occur both in the local tumour microenvironment and systemically. Neurons and glial cells communicate directly with malignant cells in the tumour microenvironment through paracrine factors and, in some cases, through neuron-to-cancer cell synapses. Additionally, indirect interactions occur at a distance through circulating signals and through influences on immune cell trafficking and function. Such cross-talk among the nervous system, immune system and cancer-both systemically and in the local tumour microenvironment-regulates pro-tumour inflammation and anti-cancer immunity. Elucidating the neuroscience of cancer, which calls for interdisciplinary collaboration among the fields of neuroscience, developmental biology, immunology and cancer biology, may advance effective therapies for many of the most difficult to treat malignancies.

Fifty years of development of neuroscientific insights into orofacial pain and its control.

When the Journal of Oral Rehabilitation was established in 1973, there was very limited understanding of the mechanisms underlying neurally based functions, including those unique to the face, mouth, and jaws (e.g. dental pain, taste, chewing, swallowing, and salivation). Since that time, technological and other advances have led to new insights into the structure, connectivity and function of cranial nerves and areas of the central nervous system (CNS) involved in orofacial functions and disorders or related functions (e.g. cognition, emotion, stress, consciousness, sleep, learning and memory). This review focusses on the advances in understanding of the neural basis of orofacial pain and its control over the past five decades. The review first briefly considers how orofacial pain conditions are now classified, diagnosed and managed. It then outlines novel insights that have been gained over this period through neuroscience research into the neural basis of these orofacial pain conditions and the clinical relevance to these insights to the diagnosis and management of these conditions. The review also identifies promising research directions and gaps in knowledge that still need to be addressed to improve the understanding, diagnosis and management of orofacial pain conditions.

Facilitation of Cell Cycle and Cellular Migration of Rat Schwann Cells by O-Carboxymethyl Chitosan to Support Peripheral Nerve Regeneration.

O-carboxymethyl chitosan (CM-chitosan), holds high potential as a valuable biomaterial for nerve guidance conduits (NGCs). However, the lack of explicit bioactivity on neurocytes and poor duration that does not match nerve repair limit the restorative effects. Herein, CM-chitosan-based NGC is designed to induce the reconstruction of damaged peripheral nerves without addition of other activation factors. CM-chitosan possesses excellent performance in vitro for nerve tissue engineering, such as increasing the organization of filamentous actin and the expression of phospho-Akt, and facilitating the cell cycle and migration of Schwann cells. Moreover, CM-chitosan exhibits increased longevity upon cross-linking (C-CM-chitosan) with 1, 4-Butanediol diglycidyl ether, and C-CM-chitosan fibers possess appropriate biocompatibility. In order to imitate the structure of peripheral nerves, multichannel bioactive NGCs are prepared from lumen fillers of oriented C-CM-chitosan fibers and outer warp-knitted chitosan pipeline. Implantation of the C-CM-chitosan NGCs to rats with 10-mm defects of peripheral nerves effectively improve nerve function reconstruction by increasing the sciatic functional index, decreasing the latent periods of heat tingling, enhancing the gastrocnemius muscle, and promoting nerve axon recovery, showing regenerative efficacy similar to that of autograft. The results lay a theoretical foundation for improving the potential high-value applications of CM-chitosan-based bioactive materials in nerve tissue engineering.

Оценка влияния хирургической реконструкции внутренней сонной артерии на гемодинамику глаза и морфофункциональные показатели зрительного анализатора у пациентов с хронической ишемической нейрооптикопатией, ассоциированной с гемодинамически значимым атеросклеротическим стенозом внутренней сонной артерии

Purpose. To evaluate the effect of carotid endarterectomy (CEA) on eye hemodynamics and morphofunctional parameters of the visual analyzer in patients with chronic ischemic neuropathy (CIN) associated with hemodynamically significant atherosclerotic stenosis of the internal carotid artery (ICA). Material and methods. The study included 50 patients (50 eyes) with unilateral manifestations of CIN. All patients underwent optical coherence tomography (OCT), Doppler ultrasound of the ophthalmic artery (OA), short posterior ciliary arteries (SPCA), central retinal artery (CRA) before and after surgical reconstruction of the ICA. Results. 24 months after CEA of the ICA, in all cases there were significant improvements in blood flow in the OA by 52.8 %, in the SPCA by 26 %, in the CRA by 30.2 %, a decrease in the thickness of the peripapillary layer of retinal nerve fibers by 9.5 % and the layer of ganglionic cells by 8 % relative to baseline (p < 0.05). Conclusion. The causes of CIN progression after ICA CEA can be considered as the consequences of induced reperfusion of the optic nerve structures and the brain. Keywords: chronic ischemic neuroopticopathy, ocular ischemic syndrome, internal carotid artery, carotid endarterectomy