Search Results (37)

Neurovascular compression syndromes (NVCS), including trigeminal neuralgia (TN) and hemifacial spasm (HFS), are characterized by disabling symptoms caused by vascular compression of cranial nerves. Although microvascular decompression is an established treatment, mechanisms linking neurovascular compression to abnormal neural activity remain incompletely understood. In this review, we integrate evidence from microanatomical, electrophysiological, and computational studies to provide a mechanistic framework for NVCS. Chronic vascular compression induces focal demyelination, redistribution of voltage-gated ion channels, ectopic impulse generation, and ephaptic transmission, leading to abnormal neuronal excitation. We further summarize emerging evidence that persistent peripheral hyperactivity may contribute to electrophysiological alterations in central neural circuits. Particular attention is given to computational approaches, including cable theory and axonal interaction models, which offer quantitative insights into abnormal synchronization and cross-excitation among nerve fibers. Recent findings regarding ion channel dysfunction, including familial TN associated with gain-of-function calcium channel variants, are also discussed. Collectively, these findings support an integrated model linking neurovascular compression to clinical manifestations, and highlight the value of combining electrophysiology and computational neuroscience to improve mechanistic understanding and to guide future therapeutic strategies for NVCS. Full article

Background: Meralgia paresthetica (MP) of the lateral femoral cutaneous is a rare, nerve-entrapment condition, often related to an inflammatory and fibrotic pathological component. Although most cases resolve with conservative management, refractory presentations may require interventional or surgical treatment. Platelet-rich plasma (PRP) has demonstrated emerging potential in peripheral neuropathies through anti-inflammatory, neurotrophic, and antifibrotic mechanisms. Case Presentation: We report the case of a 64-year-old professional scuba diving instructor with occupational MP related to repetitive compression from a tight lead weight belt. Symptoms persisted for six months despite conservative therapies. Clinical examination supported lateral femoral cutaneous nerve (LFCN) entrapment. The patient underwent three serial perineural PRP injections prepared from autologous blood and administered along the inguinal course of the nerve. Progressive symptom reduction was observed after each session, reaching approximately 90% improvement at two months. At six months, the patient was pain-free and had returned to full professional activity without limitations. Discussion: Occupational microcompression may induce intraneural edema, ischemia, and perineural fibrosis, creating a biological substrate amenable to regenerative intervention. PRP delivers concentrated growth factors capable of promoting axonal regeneration, angiogenesis, and modulation of the neuroinflammatory microenvironment. Preclinical and clinical evidence in other compressive neuropathies supports this translational rationale. Conclusions: Perineural PRP infiltration may represent a safe and promising regenerative strategy for refractory occupational MP. Controlled clinical studies are needed to define optimal protocols, patient selection criteria, and long-term efficacy in peripheral compressive neuropathies. Full article

Traumatic injuries often result in nerve tissue damage and functional deficits due to limited regeneration. Silk fibroin, a biopolymer with inherent biocompatibility and tunable properties, is a promising material for 3D-bioprinted neural tissue scaffolds. This review highlights recent advancements in silk-derived composite scaffolds, often incorporating additional materials like collagen or conductive polymers to enhance their performance. This review examines how material composition, scaffold architecture, and fabrication strategy influence biological response and functional recovery. This comprehensive review follows PRISMA guidelines and uses comprehensive searches of PubMed, MEDLINE, Embase, Web of Science, Cochrane Central, and ClinicalTrials.gov for studies published through 2025. Studies were screened for eligibility based on substance type, mechanical properties, production methods, and outcomes. Findings were synthesized qualitatively. Twelve studies were included, comprising rat (50%), canine (8.3%), and in vitro (41.7%) models. Analysis reveals that silk fibroin acts as a highly adaptable mechanical backbone. It can consistently integrate with bioactive additives (collagen, dECM) or conductive polymers (Polypyrrole, MXene) to meet specific therapeutic demands. For spinal cord injuries, composites reached a compressive modulus capable of resisting physiological pressures and preventing scaffold collapse. In soft tissue applications, silk–hydrogel blends provided localized release of exosomes and small molecules during the acute injury phase, reducing neuroinflammatory markers. Additionally, adding conductive materials allowed the scaffolds to bridge electrical gaps and promote Schwann cell proliferation and neuronal differentiation. Furthermore, 3D bioprinting enabled the creation of defined microchannels that replicate native fascicular architecture. In vivo outcomes consistently showed superior axonal regeneration, myelination, and synaptic reconnection compared to controls, correlating with significant improvements in electrophysiological and motor function. This review highlights the clinical potential of silk fibroin-based 3D-printed biomaterials for nerve regeneration, including neural repair and neural tissue engineering. More recent studies place greater emphasis on integrating mechanical, architectural, and biological considerations into scaffold design, resulting in increasingly multifunctional scaffold systems. Despite promising efficacy, the heterogeneity of fabrication methods and the predominance of rodent models highlight the need for standardized protocols and evaluations in relevant models to facilitate clinical translation. Full article

Two accelerated magnetic resonance imaging (MRI) protocols for pediatric brain imaging, GOBrain and Deep Resolve Swift Brain, developed by Siemens Healthineers (Erlangen, Germany), were evaluated in a series of clinically relevant pediatric cases at 3 Tesla. Pediatric patients are particularly prone to motion, may be uncooperative, and often require sedation, especially in emergency settings. Consequently, there is a persistent clinical demand for fast brain MRI protocols that provide diagnostically sufficient image quality while minimizing examination time. Contemporary turbo spin-echo (TSE)-based clinical protocols commonly integrate parallel imaging (PI) and simultaneous multi-slice (SMS) techniques to achieve substantial reductions in scan time. Recent advances in three-dimensional volumetric encoding, compressed sensing, and deep learning (DL)-based reconstruction have further mitigated geometry-factor-related noise amplification, enabling higher acceleration factors (GOBrain). In parallel, echo-planar imaging (EPI) has emerged as a promising approach for ultrafast multi-contrast imaging. To overcome the limitations of single-shot EPI, a multi-shot EPI-based brain MRI protocol combined with the DL-based reconstruction method Deep Resolve Swift Brain has been developed. This approach leverages the efficiency of EPI while improving image quality. Using these accelerated protocols, a comprehensive diagnostic multi-contrast brain MRI examination, particularly suited to triage and emergency imaging, can be completed in minutes. This case overview, including therapy-related leukencephalopathy in acute lymphoblastic leukemia (ALL), a brain abscess, traumatic diffuse axonal injury (DAI), a posterior circulation infarction due to vertebral artery dissection, leuokostasis syndrome, and a posterior fossa tumor with obstructive hydrocephalus, demonstrates the potential clinical feasibility of both protocols in pediatric neuroimaging. Both protocols position them as supplementary options alongside established imaging protocols, while dedicated high-resolution protocols might remain necessary for subtle pathological findings, such as focal cortical dysplasia, and for neuronavigation until larger comparative studies are available. Full article

Currently, Kronecker Matrix–Matrix Multiplication play a crucial role in many advanced applications across science and engineering, such as Quantum Computing (Tensor Representation of Quantum States, Quantum Gate Construction), Machine Learning and Data Science (Kernel Methods, Tensor Decompositions), and Signal and Image Processing (Multi-dimensional Filtering, Compression Algorithms). However, the implementation of the Kronecker Matrix–Matrix Multiplication increasingly relies on systems with enhanced computational capabilities. Specifically, current implementations expend large amounts of external memory and requires a large number of processing units to perform this operation. As is commonly acknowledged, cutting-edge high-performance computing schemes still faces limitations in terms of energy and performance due to the bottleneck in data transfer between processing units and memory. To mitigate this limitation, memory processing units (MPUs) enable direct computation on in-memory data, reducing latency and eliminating the need for data transfer. On the other hand, spiking neural P systems, with their inherent parallelism and distributed processing capabilities, are therefore well-suited as foundational components for implementing such memory architectures efficiently. From the mathematical point of view, we present for the first time a neural, synaptic, and dendritic model to support the Kronecker Matrix–Matrix multiplication. To this end, the proposed spiking neural P system with their cutting-edge variants, such as anti-spikes, communication on request, synaptic weights, and dendritic–axonal delays, facilitates the creation of neural memory cells and spike-based routers. Hence, these elements potentially allow the design of novel processing memory architectures that markedly enhance data transfer efficiency between computational units and memory. Full article

The aim of this study was to investigate the pathology of hearing loss caused by cochleo-vestibular schwannoma. Surgical specimens have demonstrated that a tumor may displace normal nerve fibers of the cochlear nerve to one side (pushing pattern) or the neoplastic cells may invade the tumor and grow between normal nerve fibers (infiltrating pattern). The goal was to study the relationship of the tumor to the remaining fibers of the cochlear nerve. Nerve fibers within all 28 tumors showed positive anti-neurofilament (NF) labeling. Axons within tumors were sometimes turned orthogonal to their original plane. Onion bulb formations were observed in tumors giving rise to early Antoni B-like regions of degeneration. Positive anti-myelin protein zero (MPZ) labeling was demonstrated. No clear capsule was found between tumor and nerve. There was a comingling of tumor and nerve fibers either with the nerve of origin or with both the nerve of origin and surrounding internal auditory canal nerves. Iba1+ macrophages were prevalent within cochleovestibular schwannomas. Our results suggest that retro cochlear mechanisms of hearing loss go beyond compression of the eighth cranial nerve, involve both myelin and axon degeneration, and suggest an inflammatory component from the earliest stage of the disease. Full article

Degenerative cervical myelopathy (DCM) is a common cause of spinal cord dysfunction in adults and is frequently accompanied by pain, a symptom that remains under-recognised despite its profound impact on quality of life. Conventional magnetic resonance imaging (MRI) is indispensable for identifying structural spinal cord compression; however, it is unable to detect early microstructural alterations, particularly those that may contribute to pain pathophysiology. This narrative review critically appraises the limitations of standard MRI in the diagnostic assessment of DCM and examines the expanding role of advanced imaging modalities—most notably diffusion tensor imaging (DTI)—in evaluating spinal cord integrity. DTI-derived parameters, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), demonstrate sensitivity to axonal and myelin injury. For example, reductions in FA and AD have been linked to axonal disruption in sensory pathways, while elevations in RD suggest demyelination, a hallmark of neuropathic pain. Despite this potential, the widespread implementation of DTI is constrained by technical heterogeneity, limited accessibility, and the absence of standardised protocols. Future research priorities include the incorporation of pain-specific imaging endpoints, longitudinal validation across diverse cohorts, and integration with artificial intelligence frameworks to enable automated analysis and predictive modelling. Collectively, these advances hold promise for enabling earlier diagnosis, refined symptom stratification, and more personalised therapeutic strategies in DCM. Full article

Background: The consequences of median nerve compression at the carpal tunnel level require a precise diagnostic evaluation before a frequently applied surgical intervention. Positive Tinel or Phalen signs are not always related to abnormal results in electroneurographic examinations of sensory and motor nerve fibers, which are intended to confirm final diagnoses, thereby confusing both surgeons and neurophysiologists. In the face of contradictory data, this study aims to reinvestigate these correlations in a randomly chosen population of patients with a primary diagnosis of carpal tunnel syndrome (CTS). Methods: Seventy-five randomly chosen patients with clinically detected CTS underwent neurophysiological studies of median nerve sensory (SNAP) and motor (CMAP) fibers conduction at the wrist. Both the median and ulnar nerves were assessed to reduce the risk of misinterpretation related to anatomical variations. Results: This study provides evidence on the relatively high utility of Phalen’s test in the early clinical detection of CTS within a general population of patients, whose positive results moderately correlate (rho = −0.327) with abnormalities in amplitudes rather than the distal latency parameters of SNAP recordings. The axonal injury type is more distinct than slowing-down impulses at the wrist following compression of the sensory nerve fibers in the early course of CTS. Positive Tinel’s test results are useful in diagnosing CTS patients with advanced axonal and demyelinating changes in the motor fibers at the wrist, which weakly correlate with prolonged latency and decreased amplitude in SNAP recordings (rho = −0.214 and rho = −0.235, respectively), but not with abnormalities in recordings of both amplitudes and latencies in CMAP electroneurography. Conclusions: The correlations between clinical signs and neurophysiological findings in CTS indicate that provocative tests, such as Phalen’s and Tinel’s, have limited diagnostic value, demonstrating only weak-to-moderate associations with neural conduction parameters. A positive Tinel’s sign should be regarded mainly as a marker of severe or chronic sensory impairment, often accompanied by motor fibers involvement in advanced pathological stages, rather than as an indicator of motor damage alone. Nerve conduction studies remain essential for confirming CTS, assessing its severity, and guiding treatment decisions, including surgical qualification. The presented correlation of clinical and functional neurophysiological results in CTS diagnosis allows us not only to specify the source and severity of the pathology of the median nerve fibers but also may influence the personalization of physiotherapeutic and surgical treatments. Full article

Peripheral nervous system (PNS) neurons, including motor neurons (MNs), possess a remarkable ability to regenerate and reinnervate target muscles following nerve injury. This process is orchestrated by a combination of intrinsic neuronal properties and extrinsic factors, with Schwann cells (SCs) playing a central role. Upon injury, SCs transition into a repair phenotype that allows axonal regeneration through molecular signaling and structural guidance. However, the identity of the SCs’ reprogramming factors is only partially known. We previously identified hydrogen peroxide (H₂O₂) as an early and key driver of nerve repair, inducing gene expression rewiring in SCs to support nerve re-growth. In this study, we quantitatively assessed the role of H₂O₂ in the activation of key pro-regenerative signaling pathways in SCs following sciatic nerve compression, specifically the extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun, which are essential for functional nerve recovery. Notably, we found that H₂O₂ neutralization does not impact degeneration, but it significantly affects the regenerative response. Collectively, our findings establish H₂O₂ as a promising regulator of the Schwann cell injury response at the injury site, linking oxidative signaling to the molecular mechanisms governing nerve regeneration. Full article

Background: Tarsal tunnel syndrome (TTS) can be divided into distal and proximal components. The latter is referred to as high TTS (HTTS) in which the tibial nerve is compressed above the location of the laciniate ligament. Although diagnosis of TTS has been shown to be enhanced by elicitation of a positive Tinel sign, no research into the utility of this provocation test has been conducted in the diagnosis of HTTS. This study aims to investigate the usefulness of the Tinel sign in diagnosing HTTS. Methods: Seventy patients with electrophysiologic confirmation of HTTS were evaluated for the presence of a positive Tinel sign over the posterior tibial nerve’s course in the area of the proximal tarsal tunnel (above the laciniate ligament). Results: Of the 70 patients, 17 had a positive Tinel sign. Thirty-eight patients (54.3%) had electrodiagnostic evidence of polyneuropathy, and 12 of them (31.6%) had a positive Tinel sign. Among the 26 patients with HTTS and polyneuropathy who did not have a Tinel sign, electrodiagnostic testing found severe axonal dysfunction in ten. Fifteen of the patients with polyneuropathy were diagnosed as having diabetes mellitus, and a Tinel sign was present in 11 of them (73.3%). The four diabetic patients without a Tinel sign had marked axonal dysfunction (motor evoked responses were absent or significantly reduced). Conclusions: The utility of the Tinel sign in patients with HTTS was found to be low; however, in the subpopulation of patients with diabetic neuropathy, the Tinel sign may be more useful. Full article

Retrograde axonal neurodegeneration along the visual pathway—either direct or trans-synaptic—has already been demonstrated in multiple sclerosis (MS), as well as in compressive, vascular, or posttraumatic lesions of the visual pathway. Optical coherence tomography (OCT) can noninvasively track macular and optic nerve changes occurring as a result of this phenomenon. Our paper aimed to review the existing literature regarding hemimacular atrophic changes in the ganglion cell layer identified using OCT examination in MS patients without prior history of optic neuritis. Homonymous hemimacular atrophy has been described in post-chiasmal MS lesions, even in patients with normal visual field results. Temporal and nasal macular OCT evaluation should be performed separately in all MS patients, in addition to an optic nerve OCT evaluation and a visual field exam. Full article

Peripheral nerves consist of delicate structures, including a rich microvascular system, that protect and nourish axons and associated Schwann cells. Nerves are sensitive to internal and external trauma, such as compression and stretching. Ulnar nerve entrapment, the second most prevalent nerve entrapment disorder after carpal tunnel syndrome, appears frequently at the elbow. Although often idiopathic, known risk factors, including obesity, smoking, diabetes, and vibration exposure, occur. It exists in all adult ages (mean age 40–50 years), but seldom affects individuals in their adolescence or younger. The patient population is heterogeneous with great co-morbidity, including other nerve entrapment disorders. Typical early symptoms are paresthesia and numbness in the ulnar fingers, followed by decreased sensory function and muscle weakness. Pre- and postoperative neuropathic pain is relatively common, independent of other symptom severity, with a risk for serious consequences. A multimodal treatment strategy is necessary. Mild to moderate symptoms are usually treated conservatively, while surgery is an option when conservative treatment fails or in severe cases. The decision to perform surgery might be difficult, and the outcome is unpredictable with the risk of complications. There is no consensus on the choice of surgical method, but simple decompression is relatively effective with a lower complication rate than transposition. Full article

Axonal degeneration resulting from optic nerve damage can lead to the progressive death of retinal ganglion cells (RGCs), culminating in irreversible vision loss. We contrasted two methods for inducing optic nerve damage: optic nerve compression (ONCo) and optic nerve crush (ONCr). These were assessed for their respective merits in simulating traumatic optic neuropathies and neurodegeneration. We also administered neural progenitor cells (NPCs) into the subtenon space to validate their potential in mitigating optic nerve damage. Our findings indicate that both ONCo and ONCr successfully induced optic nerve damage, as shown by increases in ischemia and expression of genes linked to neuronal regeneration. Post NPC injection, recovery in the expression of neuronal regeneration-related genes was more pronounced in the ONCo model than in the ONCr model, while inflammation-related gene expression saw a better recovery in ONCr. In addition, the proteomic analysis of R28 cells in hypoxic conditions identified Vps35 and Syntaxin12 genes. Vps35 preserved the mitochondrial function in ONCo, while Syntaxin12 appeared to restrain inflammation via the Wnt/β-catenin signaling pathway in ONCr. NPCs managed to restore damaged RGCs by elevating neuroprotection factors and controlling inflammation through mitochondrial homeostasis and Wnt/β-catenin signaling in hypoxia-injured R28 cells and in both animal models. Our results suggest that ischemic injury and crush injury cause optic nerve damage via different mechanisms, which can be effectively simulated using ONCo and ONCr, respectively. Moreover, cell-based therapies such as NPCs may offer promising avenues for treating various optic neuropathies, including ischemic and crush injuries. Full article

Epidural administration is the leading therapeutic option for the management of pain associated with lumbar spinal stenosis (LSS), which is characterized by compression of the nerve root due to narrowing of the spinal canal. Corticosteroids are effective in alleviating LSS-related pain but can lead to complications with long-term use. Recent studies have focused on identifying promising medications administered epidurally to affected spinal regions. In this study, we aimed to investigate the effectiveness of harpagoside (HAS) as an epidural medication in rats with LSS. HAS at various concentrations was effective for neuroprotection against ferrous sulfate damage and consequent promotion of axonal outgrowth in primary spinal cord neurons. When two concentrations of HAS (100 and 200 μg/kg) were administered to the rat LSS model via the epidural space once a day for 4 weeks, the inflammatory responses around the silicone block used for LSS were substantially reduced. Consistently, pain-related factors were significantly suppressed by the epidural administration of HAS. The motor functions of rats with LSS significantly improved. These findings suggest that targeted delivery of HAS directly to the affected area via epidural injection holds promise as a potential treatment option for the recovery of patients with LSS. Full article

Biomaterials may enhance neural repair after spinal cord injury (SCI) and testing their functionality in large animals is essential to achieve successful clinical translation. This work developed a porcine contusion/compression SCI model to investigate the consequences of myelotomy and implantation of fibrin gel containing biofunctionalized carbon microfibers (MFs). Fourteen pigs were distributed in SCI, SCI/myelotomy, and SCI/myelotomy/implant groups. An automated device was used for SCI. A dorsal myelotomy was performed on the lesion site at 1 day post-injury for removing cloths and devitalized tissue. Bundles of MFs coated with a conducting polymer and cell adhesion molecules were embedded in fibrin gel and used to bridge the spinal cord cavity. Reproducible lesions of about 1 cm in length were obtained. Myelotomy and lesion debridement caused no further neural damage compared to SCI alone but had little positive effect on neural regrowth. The MFs/fibrin gel implant facilitated axonal sprouting, elongation, and alignment within the lesion. However, the implant also increased lesion volume and was ineffective in preventing fibrosis, thus precluding functional neural regeneration. Our results indicate that myelotomy and lesion debridement can be advantageously used for implanting MF-based scaffolds. However, the implants need refinement and pharmaceuticals will be necessary to limit scarring. Full article