scholarly journals 4.7-T diffusion tensor imaging of acute traumatic peripheral nerve injury

2015 ◽  
Vol 39 (3) ◽  
pp. E9 ◽  
Author(s):  
Richard B. Boyer ◽  
Nathaniel D. Kelm ◽  
D. Colton Riley ◽  
Kevin W. Sexton ◽  
Alonda C. Pollins ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
High Resolution ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Diffusion Tensor ◽  
Ex Vivo ◽  
Nerve Fibers ◽  
Nerve Transection ◽  
Nerve Injuries

Diagnosis and management of peripheral nerve injury is complicated by the inability to assess microstructural features of injured nerve fibers via clinical examination and electrophysiology. Diffusion tensor imaging (DTI) has been shown to accurately detect nerve injury and regeneration in crush models of peripheral nerve injury, but no prior studies have been conducted on nerve transection, a surgical emergency that can lead to permanent weakness or paralysis. Acute sciatic nerve injuries were performed microsurgically to produce multiple grades of nerve transection in rats that were harvested 1 hour after surgery. High-resolution diffusion tensor images from ex vivo sciatic nerves were obtained using diffusion-weighted spin-echo acquisitions at 4.7 T. Fractional anisotropy was significantly reduced at the injury sites of transected rats compared with sham rats. Additionally, minor eigenvalues and radial diffusivity were profoundly elevated at all injury sites and were negatively correlated to the degree of injury. Diffusion tensor tractography showed discontinuities at all injury sites and significantly reduced continuous tract counts. These findings demonstrate that high-resolution DTI is a promising tool for acute diagnosis and grading of traumatic peripheral nerve injuries.

scholarly journals Diffusion tensor imaging to visualize axons in the setting of nerve injury and recovery

2015 ◽  
Vol 39 (3) ◽  
pp. E10 ◽  
Author(s):  
Thomas Anthony Gallagher ◽  
Neil G. Simon ◽  
Michel Kliot
Keyword(s):  
Diffusion Tensor Imaging ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerves ◽  
Diffusion Tensor ◽  
Nerve Fibers ◽  
Accurate Localization ◽  
Peripheral Nerve Trauma ◽  
Nerve Trauma ◽  
Diffusion Tensor Imaging Dti

Successful management of peripheral nerve trauma relies on accurate localization of the injury and grading of the severity of nerve injury to determine whether surgical intervention is required. Existing techniques, such as electrodiagnostic studies and conventional imaging modalities, provide important information, but are limited by being unable to distinguish severe nerve lesions in continuity that will recover from those that will not. Diffusion tensor imaging (DTI) and tractography of peripheral nerves provide a novel technique to localize and grade nerve injury, by assessing the integrity of the nerve fibers across the site of nerve injury. Diffusion tensor imaging and tractography also hold promise as markers of early nerve regeneration, prior to clinical and electrodiagnostic evidence of recovery. In the present review, the techniques of peripheral nerve DTI and tractography are discussed with respect to peripheral nerve trauma, with illustrative cases demonstrating potential roles of these novel approaches.

scholarly journals Initial findings in traumatic peripheral nerve injury and repair with diffusion tensor imaging

2021 ◽  
Author(s):  
Michael D. Pridmore ◽  
Gabriella E. Glassman ◽  
Alonda C. Pollins ◽  
Isaac V. Manzanera Esteve ◽  
Brian C. Drolet ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Diffusion Tensor ◽  
Injury And Repair

scholarly journals Establishment of a Sheep Model for Hind Limb Peripheral Nerve Injury: Common Peroneal Nerve

2021 ◽  
Vol 22 (3) ◽  
pp. 1401
Author(s):  
Rui D. Alvites ◽  
Mariana V. Branquinho ◽  
Ana C. Sousa ◽  
Federica Zen ◽  
Monica Maurina ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Peroneal Nerve ◽  
Common Peroneal Nerve ◽  
Small Sample ◽  
Therapeutic Options ◽  
Nerve Injuries ◽  
Sheep Model ◽  
The Common

Thousands of people worldwide suffer from peripheral nerve injuries and must deal daily with the resulting physiological and functional deficits. Recent advances in this field are still insufficient to guarantee adequate outcomes, and the development of new and compelling therapeutic options require the use of valid preclinical models that effectively replicate the characteristics and challenges associated with these injuries in humans. In this study, we established a sheep model for common peroneal nerve injuries that can be applied in preclinical research with the advantages associated with the use of large animal models. The anatomy of the common peroneal nerve and topographically related nerves, the functional consequences of its injury and a neurological examination directed at this nerve have been described. Furthermore, the surgical protocol for accessing the common peroneal nerve, the induction of different types of nerve damage and the application of possible therapeutic options were described. Finally, a preliminary morphological and stereological study was carried out to establish control values for the healthy common peroneal nerves regarding this animal model and to identify preliminary differences between therapeutic methods. This study allowed to define the described lateral incision as the best to access the common peroneal nerve, besides establishing 12 and 24 weeks as the minimum periods to study lesions of axonotmesis and neurotmesis, respectively, in this specie. The post-mortem evaluation of the harvested nerves allowed to register stereological values for healthy common peroneal nerves to be used as controls in future studies, and to establish preliminary values associated with the therapeutic performance of the different applied options, although limited by a small sample size, thus requiring further validation studies. Finally, this study demonstrated that the sheep is a valid model of peripheral nerve injury to be used in pre-clinical and translational works and to evaluate the efficacy and safety of nerve injury therapeutic options before its clinical application in humans and veterinary patients.

scholarly journals Permanent central synaptic disconnection of proprioceptors after nerve injury and regeneration. I. Loss of VGLUT1/IA synapses on motoneurons

2011 ◽  
Vol 106 (5) ◽  
pp. 2450-2470 ◽  
Author(s):  
Francisco J. Alvarez ◽  
Haley E. Titus-Mitchell ◽  
Katie L. Bullinger ◽  
Michal Kraszpulski ◽  
Paul Nardelli ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Nerve Injury ◽  
Cell Body ◽  
Peripheral Nerve Injury ◽  
Motor Coordination ◽  
Electrophysiological Study ◽  
Peripheral Nerve Injuries ◽  
Nerve Injuries ◽  
Ia Afferent ◽  
Axon Collaterals

Motor and sensory proprioceptive axons reinnervate muscles after peripheral nerve transections followed by microsurgical reattachment; nevertheless, motor coordination remains abnormal and stretch reflexes absent. We analyzed the possibility that permanent losses of central IA afferent synapses, as a consequence of peripheral nerve injury, are responsible for this deficit. VGLUT1 was used as a marker of proprioceptive synapses on rat motoneurons. After nerve injuries synapses are stripped from motoneurons, but while other excitatory and inhibitory inputs eventually recover, VGLUT1 synapses are permanently lost on the cell body (75–95% synaptic losses) and on the proximal 100 μm of dendrite (50% loss). Lost VGLUT1 synapses did not recover, even many months after muscle reinnervation. Interestingly, VGLUT1 density in more distal dendrites did not change. To investigate whether losses are due to VGLUT1 downregulation in injured IA afferents or to complete synaptic disassembly and regression of IA ventral projections, we studied the central trajectories and synaptic varicosities of axon collaterals from control and regenerated afferents with IA-like responses to stretch that were intracellularly filled with neurobiotin. VGLUT1 was present in all synaptic varicosities, identified with the synaptic marker SV2, of control and regenerated afferents. However, regenerated afferents lacked axon collaterals and synapses in lamina IX. In conjunction with the companion electrophysiological study [Bullinger KL, Nardelli P, Pinter MJ, Alvarez FJ, Cope TC. J Neurophysiol (August 10, 2011). doi:10.1152/jn.01097.2010], we conclude that peripheral nerve injuries cause a permanent retraction of IA afferent synaptic varicosities from lamina IX and disconnection with motoneurons that is not recovered after peripheral regeneration and reinnervation of muscle by sensory and motor axons.

scholarly journals High-resolution live imaging reveals axon-glia interactions during peripheral nerve injury and repair in zebrafish

2015 ◽  
Vol 8 (6) ◽  
pp. 553-564 ◽  
Author(s):  
Y. Xiao ◽  
A. Faucherre ◽  
L. Pola-Morell ◽  
J. M. Heddleston ◽  
T.-L. Liu ◽  
...  
Keyword(s):  
High Resolution ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Live Imaging ◽  
Injury And Repair

Long-Tapered Double Needle Used to Reduce Needle Stick Nerve Injury

1997 ◽  
Vol 22 (2) ◽  
pp. 157-160 ◽  
Author(s):  
Masaaki Maruyama
Keyword(s):  
Peripheral Nerve ◽  
Nerve Injury ◽  
Nerve Block ◽  
Type A ◽  
Nerve Fibers ◽  
Nerve Injuries ◽  
Anesthetic Solution ◽  
New Type ◽  
Histologic Specimen ◽  
Hematoxylin Eosin

Background and ObjectivesNeedle trauma may cause peripheral nerve injuries during performance of peripheral nerve block.MethodsFour types of 21-gauge needles for regional anesthesia were compared: a beveled nerve block needle (Quincke type); a short-tapered needle with a side orifice (Whitacre type); a long-tapered needle with a side orifice (Sprotte type); and a long-tapered double needle combining an inner pencil-point fine needle with an outer truncated conical needle (a new type). This new needle was developed to reduce the potential for nerve injury while retaining a suitable flow rate of anesthetic solution and the ability to inject the solution precisely at the point of paresthesia elicited by the tip. Each type of needle was used to produce puncture injuries to rabbit sciatic nerves. Eighteen specimens were studied within each needle group. The beveled needle was used to produce two different types of nerve injuries by inserting it either transverse or longitudinal to the nerve fibers. Each histologic specimen of the nerve with the needle puncture was surfacestained with hematoxylin-eosin and Bodian's method. Subsequently, the number of damaged axons was histomorphologically counted and statistically evaluated.ResultsBoth long-tapered needles produced significantly fewer transected axons than the beveled needle inserted with the bevel longitudinal to the nerve fibers.ConclusionThe long-tapered needles produced the least number of transected nerve fibers after sciatic nerve puncture.

scholarly journals Recovery of Peripheral Nerve with Massive Loss Defect by Tissue Engineered Guiding Regenerative Gel

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Shimon Rochkind ◽  
Zvi Nevo
Keyword(s):  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Preclinical Study ◽  
Significant Loss ◽  
Peripheral Nerve Injuries ◽  
Nerve Injuries ◽  
Reconstructive Procedures ◽  
Nerve Conduits

Objective. Guiding Regeneration Gel (GRG) was developed in response to the clinical need of improving treatment for peripheral nerve injuries and helping patients regenerate massive regional losses in peripheral nerves. The efficacy of GRG based on tissue engineering technology for the treatment of complete peripheral nerve injury with significant loss defect was investigated.Background. Many severe peripheral nerve injuries can only be treated through surgical reconstructive procedures. Such procedures are challenging, since functional recovery is slow and can be unsatisfactory. One of the most promising solutions already in clinical practice is synthetic nerve conduits connecting the ends of damaged nerve supporting nerve regeneration. However, this solution still does not enable recovery of massive nerve loss defect.The proposed technologyis a biocompatible and biodegradable gel enhancing axonal growth and nerve regeneration. It is composed of a complex of substances comprising transparent, highly viscous gel resembling the extracellular matrix that is almost impermeable to liquids and gasses, flexible, elastic, malleable, and adaptable to various shapes and formats.Preclinical studyon rat model of peripheral nerve injury showed that GRG enhanced nerve regeneration when placed in nerve conduits, enabling recovery of massive nerve loss, previously unbridgeable, and enabled nerve regeneration at least as good as with autologous nerve graft “gold standard” treatment.

scholarly journals Relationship of Anti-interleukin-6 Receptor Antibody to Interleukin-6 Level and Inducible Nitrite Oxide Levels in Peripheral Nerve Injury in Chronic Constriction Injury-Induced Rats: A Case-Control Study in Indonesia

2022 ◽  
Vol 10 (A) ◽  
pp. 1-5
Author(s):  
Riki Sukiandra ◽  
Eti Yerizel ◽  
Yuliarni Syafrita ◽  
Eryati Darwin
Keyword(s):  
Neuropathic Pain ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Interleukin 6 ◽  
Peripheral Nerve Injury ◽  
Sandwich Elisa ◽  
Peripheral Nerve Injuries ◽  
Nerve Injuries ◽  
Receptor Antibody ◽  
Male Wistar Rats

BACKGROUND: Interleukin-6 (IL-6) and inducible Nitric oxide Synthase (iNOS) have an effect on neuropathic pain in the inflammatory process in peripheral nerve injuries. AIM: This study aims to examine the effect of anti-IL-6 receptor antibody on IL-6 and iNOS levels as a consideration for the treatment of neuropathic pain in a rat model of peripheral nerve injury. METHODS: Twenty-eight young adult male Wistar rats were treated for peripheral nerve injury and then divided into two groups. Fourteen treatment groups (Group P) were given anti-IL-6 receptor antibody by injection at a dose of 100 g/day by injection into the saphenous vein in the rat’s leg for 3 days. In both groups, the serum IL-6 and iNOS levels were assessed on the 3rd day after administration of anti-IL-6 receptor antibody in group P, using the sandwich ELISA method. RESULTS: The results showed that the administration of anti-IL-6 receptor antibody did not have a significant effect on reducing IL-6 and iNOS levels in group P (p > 0.05). Administration of anti-IL-6 receptor antibody had more effect on IL-6 levels on iNOS levels, where a decrease in IL-6 levels caused a decrease in iNOS levels in group P (p = 0.004 and r = 0.693). CONCLUSIONS: We conclude that the present administration of anti-IL-6 receptor antibody cannot be considered as a treatment for neuropathic pain in peripheral nerve injuries, but can be used to influence IL-6 levels on iNOS levels.

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