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 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.

Changes in Crossed Spinal Reflexes After Peripheral Nerve Injury and Repair

2002 ◽  
Vol 87 (4) ◽  
pp. 1763-1771 ◽  
Author(s):  
Antoni Valero-Cabré ◽  
Xavier Navarro
Keyword(s):  
Sciatic Nerve ◽  
Action Potential ◽  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Tibialis Anterior ◽  
Tibial Nerve ◽  
Spinal Reflexes ◽  
Injury And Repair

We investigated the changes induced in crossed extensor reflex responses after peripheral nerve injury and repair in the rat. Adults rats were submitted to non repaired sciatic nerve crush (CRH, n = 9), section repaired by either aligned epineurial suture (CS, n = 11) or silicone tube (SIL4, n = 13), and 8 mm resection repaired by tubulization (SIL8, n = 12). To assess reinnervation, the sciatic nerve was stimulated proximal to the injury site, and the evoked compound muscle action potential (M and H waves) from tibialis anterior and plantar muscles and nerve action potential (CNAP) from the tibial nerve and the 4th digital nerve were recorded at monthly intervals for 3 mo postoperation. Nociceptive reinnervation to the hindpaw was also assessed by plantar algesimetry. Crossed extensor reflexes were evoked by stimulation of the tibial nerve at the ankle and recorded from the contralateral tibialis anterior muscle. Reinnervation of the hindpaw increased progressively with time during the 3 mo after lesion. The degree of muscle and sensory target reinnervation was dependent on the severity of the injury and the nerve gap created. The crossed extensor reflex consisted of three bursts of activity (C1, C2, and C3) of gradually longer latency, lower amplitude, and higher threshold in control rats. During follow-up after sciatic nerve injury, all animals in the operated groups showed recovery of components C1 and C2 and of the reflex H wave, whereas component C3 was detected in a significantly lower proportion of animals in groups with tube repair. The maximal amplitude of components C1 and C2 recovered to values higher than preoperative values, reaching final levels between 150 and 245% at the end of the follow-up in groups CRH, CS, and SIL4. When reflex amplitude was normalized by the CNAP amplitude of the regenerated tibial nerve, components C1 (300–400%) and C2 (150–350%) showed highly increased responses, while C3 was similar to baseline levels. In conclusion, reflexes mediated by myelinated sensory afferents showed, after nerve injuries, a higher degree of facilitation than those mediated by unmyelinated fibers. These changes tended to decline toward baseline values with progressive reinnervation but still remained significant 3 mo after injury.

scholarly journals A comparison of two-dimensional and three-dimensional techniques for determining the kinematic patterns for hindlimb obstacle clearance during sheep locomotion.

2020 ◽  
Author(s):  
Camila Cardoso Diogo ◽  
Bárbara Fonseca ◽  
Francisca S.M. Almeida ◽  
Luís Maltez da Costa ◽  
José Eduardo Pereira ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Time Course ◽  
Objective Assessment ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Ovine Model ◽  
Obstacle Clearance ◽  
Injury And Repair

Abstract Background: Analysis of locomotion is often used as a measure for impairment and recovery following experimental peripheral nerve injury. Compared to rodents, sheep offer several attractive features as an experimental model for studying peripheral nerve regeneration. There are no studies on locomotion outcomes after peripheral nerve injury and repair in the sheep model. In the present study, we performed and compared two-dimensional (2D) and, for the first time, three-dimensional (3D) hindlimb kinematics during obstacle avoidance in the ovine model. This study aimed to obtain kinematic data to serve as a template for an objective assessment of the ankle joint motion in future studies of common peroneal nerve (CP) injury and repair in the ovine model. Results: The strategy used by the sheep to bring the hindlimb over a moderately high obstacle, set to 10% of its hindlimb length, was the pronounced knee, ankle and metatarsophalangeal flexion when approaching and clearing the obstacle. Despite the overall time course kinematic patterns about the hip, knee, ankle, and metatarsophalangeal were identical, we found significant differences between values of the 2D and 3D joint angular motion. Conclusions: Our results show that the most apparent changes that occurred during the gait cycle were for the ankle and metatarsophalangeal joints, whereas the hip and knee joints were much less affected. Data and techniques described here are likely to be useful for an objective assessment of altered gait after CP injury and repair in an ovine model.

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

Assessment of Sensibility after Nerve Injury and Repair: A Systematic Review of Evidence for Validity, Reliability and Responsiveness of Tests

2005 ◽  
Vol 30 (3) ◽  
pp. 252-264 ◽  
Author(s):  
C. JEROSCH-HEROLD
Keyword(s):  
Peripheral Nerve ◽  
Psychometric Properties ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Standardized Test ◽  
Nerve Suture ◽  
Threshold Test ◽  
Injury And Repair ◽  
Robust Measures ◽  
Monofilament Test

Recovery of sensibility after peripheral nerve injury and repair needs to be assessed using psychometrically robust measures. In this study the literature was reviewed to identify what tests are available to quantify sensibility and to assess their validity, reliability and responsiveness. The databases Medline, CINAHL, Embase and AMED were searched for studies reporting the psychometric properties of sensibility tests. While there is a plethora of tests and studies reporting the outcomes after peripheral nerve suture only a few of the tests have evidence of validity, reliability and responsiveness. Currently the touch threshold test using monofilaments such as the Weinstein Enhanced Sensory Test (WEST) or Semmes–Weinstein Monofilament Test (SWMT) and the shape–texture identification (STI™) test for tactile gnosis are the only tests which meet criteria for a standardized test and have had their psychometric properties evaluated and quantified.

scholarly journals Estimations of topographically correct regeneration to nerve branches and skin after peripheral nerve injury and repair

2006 ◽  
Vol 1098 (1) ◽  
pp. 49-60 ◽  
Author(s):  
Anna Puigdellívol-Sánchez ◽  
Alberto Prats-Galino ◽  
Carl Molander
Keyword(s):  
Peripheral Nerve ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Injury And Repair

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.

Sign in / Sign up

Export Citation Format

Share Document