Segmental nerve enlargement in CMT4J

2020 ◽  
Vol 61 (6) ◽  
Author(s):  
Ryan Castoro ◽  
James Crisp ◽  
James B. Caress ◽  
Jun Li ◽  
Michael S. Cartwright
Keyword(s):  
Segmental Nerve ◽  
Nerve Enlargement

Origin of somatosensory evoked responses recorded from the cervical skin surface

1978 ◽  
Vol 48 (6) ◽  
pp. 980-984 ◽  
Author(s):  
Koki Shimoji ◽  
Hiroyuki Shimizu ◽  
Yoichi Maruyama
Keyword(s):  
Cauda Equina ◽  
Skin Surface ◽  
Peak Latency ◽  
Spinal Root ◽  
Negative Wave ◽  
Content Type ◽  
Segmental Nerve ◽  
Strong Stimulation ◽  
Somatosensory Evoked Response ◽  
Two Peaks

✓ Somatosensory evoked response from the cervical skin surface over the spine (the cervical SER) was recorded, and compared with the cord dorsum potential (CDP) simultaneously recorded from the posterior epidural space at the same segment. The cervical SER evoked by segmental nerve stimulation consisted of an initially positive spike (P1), the peak latency being the same as that of the P1 of the CDP, followed by a smaller negative wave with two peaks. The latency of the second peak of the negative wave (N1) coincided with that of the N1 of the CDP. Subsequent to this negative wave, a slow positive wave (P2) with peak latency similar to that of the P2 of the CDP, could be noticed in some subjects. The cervical SER could not be evoked even by strong stimulation of the cauda equina. Thus, the cervical SER might reflect a segmental phenomenon rather than the conducted potential along the cord, and originate from the spinal root and cord in the same way as the segmentally evoked CDP.

Transplantation of Schwann cells in a collagen tube for the repair of large, segmental peripheral nerve defects in rats

2013 ◽  
Vol 119 (3) ◽  
pp. 720-732 ◽  
Author(s):  
Yerko A. Berrocal ◽  
Vania W. Almeida ◽  
Ranjan Gupta ◽  
Allan D. Levi
Keyword(s):  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
Schwann Cells ◽  
Nerve Injury ◽  
Peripheral Nerve Injury ◽  
Fluorescent Protein ◽  
Control Groups ◽  
Myelinated Axons ◽  
Segmental Nerve ◽  
Green Fluorescent

Object Segmental nerve defects pose a daunting clinical challenge, as peripheral nerve injury studies have established that there is a critical nerve gap length for which the distance cannot be successfully bridged with current techniques. Construction of a neural prosthesis filled with Schwann cells (SCs) could provide an alternative treatment to successfully repair these long segmental gaps in the peripheral nervous system. The object of this study was to evaluate the ability of autologous SCs to increase the length at which segmental nerve defects can be bridged using a collagen tube. Methods The authors studied the use of absorbable collagen conduits in combination with autologous SCs (200,000 cells/μl) to promote axonal growth across a critical size defect (13 mm) in the sciatic nerve of male Fischer rats. Control groups were treated with serum only–filled conduits of reversed sciatic nerve autografts. Animals were assessed for survival of the transplanted SCs as well as the quantity of myelinated axons in the proximal, middle, and distal portions of the channel. Results Schwann cell survival was confirmed at 4 and 16 weeks postsurgery by the presence of prelabeled green fluorescent protein–positive SCs within the regenerated cable. The addition of SCs to the nerve guide significantly enhanced the regeneration of myelinated axons from the nerve stump into the proximal (p < 0.001) and middle points (p < 0.01) of the tube at 4 weeks. The regeneration of myelinated axons at 16 weeks was significantly enhanced throughout the entire length of the nerve guide (p < 0.001) as compared with their number in a serum–only filled tube and was similar in number compared with the reversed autograft. Autotomy scores were significantly lower in the animals whose sciatic nerve was repaired with a collagen conduit either without (p < 0.01) or with SCs (p < 0.001) when compared with a reversed autograft. Conclusions The technique of adding SCs to a guidance channel significantly enhanced the gap distance that can be repaired after peripheral nerve injury with long segmental defects and holds promise in humans. Most importantly, this study represents some of the first essential steps in bringing autologous SC-based therapies to the domain of peripheral nerve injuries with long segmental defects.

Neural Patterns Associated with Ventilatory Movements in Dragonfly Larvae

1970 ◽  
Vol 52 (1) ◽  
pp. 167-175
Author(s):  
P. J. MILL
Keyword(s):  
Control System ◽  
Motor Activity ◽  
Action Potentials ◽  
Motor Units ◽  
The Other ◽  
Ventilatory Control ◽  
Expiratory Phase ◽  
Segmental Nerve ◽  
Ventral Muscle ◽  
Stimulation Of

1. Rhythmic bursts of motor activity associated with the expiratory phase of ventilation have been recorded from the second lateral segmental nerves of posterior abdominal ganglia in Aeshna and Anax larvae. 2. In Aeshna the rhythmic expiratory bursts contain one, or sometimes two, motor units; whereas in Anax there are almost invariably three units. In both animals only one unit is associated with action potentials in the respiratory dorso-ventral muscle. 3. Motor activity synchronized with the expiratory bursts in the second nerves has been recorded from the other lateral nerves and from the last unpaired nerve. In addition the fifth lateral nerves carry inspiratory bursts. 4. It has been confirmed that stimulation of a first segmental nerve can re-set the ventilatory rhythm by initiating an expiratory burst in the second nerves. The original frequency is immediately resumed on cessation of stimulation. 5. The nature of the ventilatory control system in dragonfly larvae is discussed in relation to other rhythmic systems in the arthropods.

Experimental Demonstration of Tongue Muscle Origin in Chick Embryos

Development ◽  
1958 ◽  
Vol 6 (4) ◽  
pp. 527-529
Author(s):  
E. M. Deuchar
Keyword(s):  
Chick Embryos ◽  
Occipital Region ◽  
Experimental Demonstration ◽  
Tongue Muscle ◽  
Segmental Nerve ◽  
Reptile Species ◽  
Tongue Muscles ◽  
Mammalian Embryos ◽  
Muscle Origin

Since in all classes of vertebrates the tongue muscles are innervated by nerve XII, a segmental nerve of the occipital region, it is usually argued on this criterion alone that they originate from occipital myotome tissue. Descriptive evidence in support of this generalization is, however, far from adequate. The most complete accounts that exist refer to one amphibian and two reptile species. In the amphibian Necturus, Platt (1897) observed that ventral outgrowths of the 3rd and 4th occipital myotomes became tongue muscles, and Edgeworth (1935) has described the development of tongue muscles in the reptiles Sphenodon and Lacerta, from ventral parts of two occipital and two cervical myotomes, all innervated by nerve XII. In avian and mammalian embryos, however, early muscle rudiments are extremely difficult to recognize with any certainty histologically.

The influence of nerve conduits diameter in motor nerve recovery after segmental nerve repair

Microsurgery ◽  
2014 ◽  
Vol 34 (8) ◽  
pp. 646-652 ◽  
Author(s):  
Guilherme Giusti ◽  
Richard H. Shin ◽  
Joo-Yup Lee ◽  
Tiago G. Mattar ◽  
Allen T. Bishop ◽  
...  
Keyword(s):  
Motor Nerve ◽  
Nerve Repair ◽  
Nerve Conduits ◽  
Segmental Nerve ◽  
Nerve Recovery

c-Fos expression in the spinal cord after acute sacral segmental nerve stimulation

2002 ◽  
Vol 21 (5) ◽  
pp. 495-501 ◽  
Author(s):  
Manabu Ishigooka ◽  
Teruhiro Nakada ◽  
Tohru Hashimoto ◽  
Dirk-Henrik Zermann ◽  
Richard A. Schmidt
Keyword(s):  
Spinal Cord ◽  
Nerve Stimulation ◽  
Segmental Nerve ◽  
Fos Expression

scholarly journals Ulnar Nerve Enlargement at the Medial Epicondyle Negatively Correlates With Nerve Conduction Velocity in Cubital Tunnel Syndrome

Hand ◽  
2018 ◽  
Vol 15 (2) ◽  
pp. 165-169
Author(s):  
T. David Luo ◽  
Amy P. Trammell ◽  
Luke P. Hedrick ◽  
Ethan R. Wiesler ◽  
Francis O. Walker ◽  
...  
Keyword(s):  
Ulnar Nerve ◽  
Nerve Conduction ◽  
Nerve Conduction Velocity ◽  
Motor Nerve ◽  
Cubital Tunnel Syndrome ◽  
Medial Epicondyle ◽  
Cubital Tunnel ◽  
Motor Nerve Conduction ◽  
Nerve Enlargement ◽  
Tunnel Syndrome

Background: In cubital tunnel syndrome (CuTS), chronic compression often occurs at the origin of the flexor carpi ulnaris at the medial epicondyle. Motor nerve conduction velocity (NCV) across the elbow is assessed preoperatively to corroborate the clinical impression of CuTS. The purpose of this study was to correlate preoperative NCV to the direct measurements of ulnar nerve size about the elbow at the time of surgery in patients with clinical and/or electrodiagnostic evidence of CuTS. Methods: Data from 51 consecutive patients who underwent cubital tunnel release over a 2-year period were reviewed. Intraoperative measurements of the decompressed nerve were taken at 3 locations: at 4 cm proximal to the medial epicondyle, at the medial epicondyle, and at the distal aspect of Osborne fascia at the flexor aponeurotic origin. Correlation analysis was performed comparing nerve size measurements to slowing of ulnar motor nerve conduction velocities (NCV) below the normal threshold of 49 m/s across the elbow. Results: Enlargement of the ulnar nerve at the medial epicondyle and nerve compression at the flexor aponeurotic origin was a consistent finding. The mean calculated cross-sectional area of the ulnar nerve was 0.21 cm2 above the medial epicondyle, 0.30 cm2 at the medial epicondyle, and 0.20 cm2 at the flexor aponeurotic origin ( P < .001). There was an inverse correlation between change in nerve diameter and NCV slowing ( r = −0.529, P < .001). Conclusions: For patients with significantly reduced preoperative NCV and clinical findings of advanced ulnar neuropathy, surgeons can expect nerve enlargement, all of which may affect their surgical decision-making.

The Response of a Proprioceptor to the Undulatory Movements of Dogfish

1969 ◽  
Vol 51 (3) ◽  
pp. 775-785 ◽  
Author(s):  
B. L. ROBERTS
Keyword(s):  
Angular Velocity ◽  
Body Wall ◽  
Maximum Velocity ◽  
The Body ◽  
Nerve Fibres ◽  
Impulse Frequency ◽  
Segmental Nerve

1. Recordings were made from segmental nerve fibres in dogfish while body-wall strips were bent sinusoidally at frequencies and angles comparable with the movements of intact fish. 2. The sensory discharge recorded from a slowly adapting mechanoreceptor in the body wall was proportional to the angular velocity and to the amplitude of the movements. 3. The receptor discharged bursts of sensory impulses during every movement cycle near to the time of maximum velocity. 4. The impulse frequency and the number of potentials in each sensory burst was dependent on the frequency of the bending movement. The number of active units depended on the angle of displacement and on the position of the receptor. 5. These experiments show that this mechanoreceptor could provide information about the frequency and the angle of bending of the body of dogfish during swimming movements.

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