MR imaging of spondylolytic spondylolisthesis: changes of intervertebral foramen and nerve root compression

International Nuclear Information System (INIS)

Kim, Ji Hyung; Chung, Tae Sub; Kim, Young Soo

1999-01-01

To evaluate the factors affecting intervertebral foramen stenosis and nerve root compression in spondylolytic spondylolisthesis. We investigated 120 intervertebral foramina of 60 patients with spondylolytic spondylolisthesis who had undergone lumbar MRI. A retrospective review of their MR images revealed the degree of intervertebral foramen stenosis and causes of nerve root compression. The relationship between disk height diminution following spondylolysis and degree of intervertebral foramen stenosis was also evaluated. Forty eight of 60 patients showed a similar degree of intervertebral foramen stenosis, and in 12 patients the degree of stenosis was different. In 110 intervertebral foramina, stenosis of both the superior and inferior compartments of intervertebral foramina was demonstrated. In 37 of 120 cases (30.8%), stenosis was mild ; in 44 of 120 (36.7%) it was modcrate, and in 29 of 120 (24.2%) it was severe. Stenosis of the inferior compartment was demonstrated in ten of 120 intervertebral foramina (8.3%). Nerve root compression was caused by posterior bulging of the intervertebral disk (65/120), descent of the pedicle (51/120), an isthmic bony segment above the site of spondylolytic (44/120), a bony spur formed at a spondylolytic site (11/120), and fibrocartilaginous callus at a spondylolytic site (5/48). In all cases there was degenerative change of the intervertebral disk at the affected level. There was no relationship between degree of disk height diminution and degree of intervertebral foramen stenosis (p > 0.05). The degree of intervertebral foramen stenosis and causes of nerve root compression in spondylolytic spondylolisthesis are variable, and MRI demonstrates them precisely. There was no positive relationship between degree of nerve root compression at an intervertebral foramen and degree of spondylolysis and degeneration of an intervertebral foramen. The degree of nerve root compression is believed to be another criterion for describing

Accuracy of Clinical Tests in Detecting Disk Herniation and Nerve Root Compression in Subjects With Lumbar Radicular Symptoms.

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Ekedahl, Harald; Jönsson, Bo; Annertz, Mårten; Frobell, Richard B

2018-04-01

To investigate the accuracy of 3 commonly used neurodynamic tests (slump test, straight-leg raise [SLR] test, femoral neurodynamic test) and 2 clinical assessments to determine radiculopathy (radiculopathy I, 1 neurologic sign; radiculopathy II, 2 neurologic signs corresponding to 1 specific nerve root) in detecting magnetic resonance imaging (MRI) findings (extrusion, subarticular nerve root compression, and foraminal nerve root compression). Validity study. Secondary care. We included subjects (N=99; mean age, 58y; 54% women) referred for epidural steroid injection because of lumbar radicular symptoms who had positive clinical and MRI findings. Positive clinical findings included the slump test (n=67), SLR test (n=50), femoral neurodynamic test (n=7), radiculopathy I (n=70), and radiculopathy II (n=33). Positive MRI findings included extrusion (n=27), subarticular nerve compression (n=14), and foraminal nerve compression (n=25). Not applicable. Accuracy of clinical tests in detecting MRI findings was evaluated using sensitivity, specificity, and receiver operating characteristics analysis with area under the curve (AUC). The slump test had the highest sensitivity in detecting extrusion (.78) and subarticular nerve compression (1.00), but the respective specificity was low (.36 and .38). Radiculopathy I was most sensitive in detecting foraminal nerve compression (.80) but with low specificity (.34). Only 1 assessment had a concurrent high sensitivity and specificity (ie, radiculopathy II) in detecting subarticular nerve compression (.71 and .73, respectively). The AUC for all tests in detecting extrusion, subarticular nerve compression, and foraminal nerve compression showed ranges of .48 to .60, .63 to .82, and .33 to .57, respectively. In general, the investigated neurodynamic tests or assessments for radiculopathy lacked diagnostic accuracy. The slump test was the most sensitive test, while radiculopathy II was the most specific test. Most interestingly, no

How should we grade lumbar disc herniation and nerve root compression? A systematic review.

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Li, Yiping; Fredrickson, Vance; Resnick, Daniel K

2015-06-01

MRI is the gold standard for evaluating the relationship of disc material to soft tissue and neural structures. However, terminologies used to describe lumbar disc herniation and nerve root compression have always been a source of confusion. A clear understanding of lumbar disc terminology among clinicians, radiologists, and researchers is vital for patient care and future research. Through a systematic review of the literature, the purpose of this article is to describe lumbar disc terminology and comment on the reliability of various nomenclature systems and their application to clinical practice. PubMed was used for our literature search using the following MeSH headings: "Magnetic Resonance Imaging and Intervertebral Disc Displacement" and "Lumbar Vertebrae" and terms "nomenclature" or "grading" or "classification". Ten papers evaluating lumbar disc herniation/nerve root compression using different grading criteria and providing information regarding intraobserver and interobserver agreement were identified. To date, the Combined Task Force (CTF) and van Rijn classification systems are the most reliable methods for describing lumbar disc herniation and nerve root compression, respectively. van Rijn dichotomized nerve roots from "definitely no root compression, possibly no root compression, indeterminate root compression, possible root compression, and definite root compression" into no root compression (first three categories) and root compression (last two categories). The CTF classification defines lumbar discs as normal, focal protrusion, broad-based protrusion, or extrusion. The CTF classification system excludes "disc bulges," which is a source of confusion and disagreement among many practitioners. This potentially accounts for its improved reliability compared with other proposed nomenclature systems. The main issue in the management of patients with lumbar disc disease and nerve root compression is correlation of imaging findings with clinical

CT evaluation of optic nerve compression in thyroid eye disease

International Nuclear Information System (INIS)

Barrett, L.; Giatt, H.J.; Burde, R.M.; Gado, M.

1986-01-01

In thyroid eye disease, visual loss due to optic nerve compression by enlarged muscles near the orbital apex requires prompt surgical decompression and must be differentiated from visual loss due to other mechanisms. Seventy-two high-resolution orbital CT scans of patients with thyroid eye disease were analyzed. From a coronal reconstruction, an easily measured ''apical index'' was determined. Average apical indices for orbits without optic neuropathy (41.0%) and with optic neuropathy (70.2%) were significantly different (P < .001). With the aid of the apical index, CT findings can be used to predict which patients with thyroid eye disease have optic nerve compression

MR images of optic nerve compression by the intracranial carotid artery. Including the patients with normal tension glaucoma

International Nuclear Information System (INIS)

Kurokawa, Hiroaki; Kin, Kiyonori; Arichi, Miwa; Ogata, Nahoko; Shimizu, Ken; Akai, Mikio; Ikeda, Koshi; Sawada, Satoshi; Matsumura, Miyo

2003-01-01

Twenty-one eyes of 12 patients with MRI-defined optic nerve compression by the intracranial carotid artery were examined to investigate whether the visual field defects result from optic nerve compression or other causes. In 4 affected eyes with 2 patients, we could not distinguish whether the visual field defects were due to optic nerve compression or normal-tension glaucoma. These patients had evidence of glaucoma-like cupping of the optic disc and visual field defects. Nine affected eyes with 7 patients were diagnosed as having compressive optic neuropathy due to unilateral optic nerve compression associated with visual field defects or non-glaucomatous visual field defects. Four of 9 affected eyes were associated with optic disc cupping of various degrees. We suggest that the glaucoma-like visual field defects and optic disc cupping may result from a compressive lesion of the anterior visual pathway. Frequently, this feature caused confusion in the differential diagnosis between optic nerve compression by carotid artery and normal-tension glaucoma. (author)

Ganglion Cyst Associated with Triangular Fibrocartilage Complex Tear That Caused Ulnar Nerve Compression

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Ugur Anil Bingol, MD

2015-03-01

Full Text Available Summary: Ganglions are the most frequently seen soft-tissue tumors in the hand. Nerve compression due to ganglion cysts at the wrist is rare. We report 2 ganglion cysts arising from triangular fibrocartilage complex, one of which caused ulnar nerve compression proximal to the Guyonʼs canal, leading to ulnar neuropathy. Ganglion cysts seem unimportant, and many surgeons refrain from performing a general hand examination.

Multiple locations of nerve compression: an unusual cause of persistent lower limb paresthesia.

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Ang, Chia-Liang; Foo, Leon Siang Shen

2014-01-01

A paucity of appreciation exists that the "double crush" phenomenon can account for persistent leg symptoms even after spinal neural decompression surgery. We present an unusual case of multiple locations of nerve compression causing persistent lower limb paresthesia in a 40-year old male patient. The patient's lower limb paresthesia was persistent after an initial spinal surgery to treat spinal lateral recess stenosis thought to be responsible for the symptoms. It was later discovered that he had peroneal muscle herniations that had caused superficial peroneal nerve entrapments at 2 separate locations. The patient obtained much symptomatic relief after decompression of the peripheral nerve. The "double crush" phenomenon and multiple levels of nerve compression should be considered when evaluating lower limb neurogenic symptoms, especially after spinal nerve root surgery. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Surgical trainees neuropraxia? An unusual case of compression of the lateral cutaneous nerve of the forearm.

LENUS (Irish Health Repository)

Seoighe, D M

2010-09-01

Compression of the lateral cutaneous nerve of the forearm is an uncommon diagnosis but has been associated with strenuous upper limb activity. We report the unique case of a 32-year-old male orthopaedic trainee who suffered this nerve palsy as a result of prolonged elbow extension and forearm pronation while the single assistant during a hip resurfacing procedure. Conservative measures were sufficient for sensory recovery to be clinically detectable after 12 weeks.

Nerve Root Compression Increases Spinal Astrocytic Vimentin in Parallel With Sustained Pain and Endothelial Vimentin in Association With Spinal Vascular Reestablishment.

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Smith, Jenell R; Lee, Jasmine; Winkelstein, Beth A

2017-10-01

Temporal immunohistochemistry analysis of spinal cord tissue from a rat model of cervical radiculopathy. The goal was to measure spinal endothelial and astrocytic vimentin expression after a painful nerve root compression to define spinal cellular expression of vimentin in the context of pain. The intermediate filament, vimentin, is expressed in a variety of cell types in the spinal cord and is modulated in response to neural pathologies. Early after nerve root compression spinal astrocytes become activated and blood-spinal cord barrier (BSCB) breakdown occurs in parallel with development of pain-related behaviors; these spinal responses remain activated as does the presence of pain. In addition to vimentin, glial fibrillary acidic protein (GFAP) expression is a hallmark of astrocyte activation. In contrast, vascular endothelial cells down-regulate vimentin expression in parallel with vascular breakdown. It is not known whether spinal astrocytes and endothelial cells modulate their expression of vimentin in response to a painful neural injury. Mechanical hyperalgesia was measured and spinal cord tissue was harvested at days 1 and 7 after a unilateral nerve root compression in rats. Vimentin was coimmunolabeled with GFAP to label astrocytes and von Willebrand factor (VWF) for endothelial cells in the spinal cord on the side of injury. Spinal astrocytic vimentin increases by day 7 after nerve root compression, corresponding to when mechanical hyperalgesia is maintained. Spinal endothelial vimentin increases as early as day 1 after a painful compression and is even more robust at day 7. The delayed elevation in spinal astrocytic vimentin corresponding to sustained mechanical hyperalgesia supports its having a relationship with pain maintenance. Further, since BSCB integrity has been shown to be reestablished by day 7 after a painful compression, endothelial expressed vimentin may help to fortify spinal vasculature contributing to BSCB stability. N/A.

Sciatic nerve compression by neurogenic heterotopic ossification: use of CT to determine surgical indications

International Nuclear Information System (INIS)

Salga, Marjorie; Jourdan, Claire; Durand, Marie-Christine; Hangard, Chloe; Carlier, Robert-Yves; Denormandie, Philippe; Genet, Francois

2015-01-01

To describe the characteristics of neurogenic heterotopic ossification (NHO) based on clinical tests, electroneuromyography (ENMG) and CT in a database of patients with lesions of the central nervous system who required sciatic nerve neurolysis along with posterior hip NHO resection, and to determine the respective roles of ENMG and CT in the management of posterior hip NHOs in patients who are unable to communicate or express pain. The consistency of the ENMG results with clinical findings, CT results and macroscopic signs of lesions was retrospectively assessed after sciatic nerve neurolysis and ablation of 55 posterior hip NHOs. Sciatic nerve neurolysis was necessary in 55 cases (47.4 %; 55 out of 116). CT showed contact of the NHO with the nerve in all cases: 5 in contact with no deflection, 3 in contact with deflection, 21 moulded into a gutter and 26 entrapped in the NHO. There were clinical signs of sciatic nerve lesion in 21.8 % of cases (12 out of 55). ENMG showed signs of sciatic nerve lesions in only 55.6 % (10 out of 18), only 4 of whom presented with clinical signs of a nerve lesion. No significant relationship was found between clinical symptoms and ENMG findings of sciatic nerve compression (n = 13, p = 0.77). Nerve compression by NHO is likely an underdiagnosed condition, particularly in patients who are unable to communicate. Diagnosis of sciatic compression by NHO should be based on regular clinical examinations and CT. ENMG is not sufficiently sensitive to be used alone for surgical decision-making. (orig.)

Sciatic nerve compression by neurogenic heterotopic ossification: use of CT to determine surgical indications

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Salga, Marjorie [Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Physical Medicine and Rehabilitation, Garches (France); Jourdan, Claire [Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Physical Medicine and Rehabilitation, Garches (France); Universite de Versailles Saint Quentin en Yvelines, Handi-Resp, (EA4047), Versailles (France); Durand, Marie-Christine [Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Neurophysiology, Garches (France); Universite de Versailles Saint Quentin en Yvelines, Groupement de Recherche Clinique et Technologique sur le Handicap (GRCTH, EA 4497), Versailles (France); Hangard, Chloe; Carlier, Robert-Yves [Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Medical Imaging, Garches (France); Denormandie, Philippe [Universite de Versailles Saint Quentin en Yvelines, Groupement de Recherche Clinique et Technologique sur le Handicap (GRCTH, EA 4497), Versailles (France); Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Orthopaedic Surgery, Garches (France); Genet, Francois [Hopital Raymond Poincare, APHP, CIC-IT 805, Department of Physical Medicine and Rehabilitation, Garches (France); Universite de Versailles Saint Quentin en Yvelines, Groupement de Recherche Clinique et Technologique sur le Handicap (GRCTH, EA 4497), Versailles (France); Military Medical Service, Hopital d' Instruction des Armees Percy, Department of Physical Medicine and Rehabilitation, Clamart (France)

2014-09-14

To describe the characteristics of neurogenic heterotopic ossification (NHO) based on clinical tests, electroneuromyography (ENMG) and CT in a database of patients with lesions of the central nervous system who required sciatic nerve neurolysis along with posterior hip NHO resection, and to determine the respective roles of ENMG and CT in the management of posterior hip NHOs in patients who are unable to communicate or express pain. The consistency of the ENMG results with clinical findings, CT results and macroscopic signs of lesions was retrospectively assessed after sciatic nerve neurolysis and ablation of 55 posterior hip NHOs. Sciatic nerve neurolysis was necessary in 55 cases (47.4 %; 55 out of 116). CT showed contact of the NHO with the nerve in all cases: 5 in contact with no deflection, 3 in contact with deflection, 21 moulded into a gutter and 26 entrapped in the NHO. There were clinical signs of sciatic nerve lesion in 21.8 % of cases (12 out of 55). ENMG showed signs of sciatic nerve lesions in only 55.6 % (10 out of 18), only 4 of whom presented with clinical signs of a nerve lesion. No significant relationship was found between clinical symptoms and ENMG findings of sciatic nerve compression (n = 13, p = 0.77). Nerve compression by NHO is likely an underdiagnosed condition, particularly in patients who are unable to communicate. Diagnosis of sciatic compression by NHO should be based on regular clinical examinations and CT. ENMG is not sufficiently sensitive to be used alone for surgical decision-making. (orig.)

Endoscopic optic nerve decompression for nontraumatic compressive optic neuropathy

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Cheng-long REN

2015-11-01

Full Text Available Objective　To describe the preliminary experience with endoscopic optic nerve decompression (EOND for nontraumatic compressive optic neuropathies (NCONs. Methods　The clinical data of 10 patients, male 5 and female 5, with a mean age of 44.3±5.1 years, who underwent EOND for visual loss (n=5 or visual deterioration (n=5 due to tumor compression in General Hospital of Armed Police Forces of China in the period from April 2013 to April 2014 were analyzed retrospectively. Preoperative and 6-month-postoperative clinical and imaging data of these patients were reviewed and analyzed. Results　Among 5 patients who lost light perception (including 2 patients with bilateral optic nerve compression before operation, 4 of them showed visual improvement to different degrees on the 7th day after operation (with improvement of bilateral visual acuity. The other 5 patients with visual impairment before operation recovered their visual acuity to different extent after the operation. All of the patients had no obvious post-operative complications. Conclusion　EOND is a safe, effective, and minimally invasive surgical technique affording recovery of visual function to NCON patients. DOI: 10.11855/j.issn.0577-7402.2015.11.12

Renal hemodynamic effects of activation of specific renal sympathetic nerve fiber groups.

Science.gov (United States)

DiBona, G F; Sawin, L L

1999-02-01

To examine the effect of activation of a unique population of renal sympathetic nerve fibers on renal blood flow (RBF) dynamics, anesthetized rats were instrumented with a renal sympathetic nerve activity (RSNA) recording electrode and an electromagnetic flow probe on the ipsilateral renal artery. Peripheral thermal receptor stimulation (external heat) was used to activate a unique population of renal sympathetic nerve fibers and to increase total RSNA. Total RSNA was reflexly increased to the same degree with somatic receptor stimulation (tail compression). Arterial pressure and heart rate were increased by both stimuli. Total RSNA was increased to the same degree by both stimuli but external heat produced a greater renal vasoconstrictor response than tail compression. Whereas both stimuli increased spectral density power of RSNA at both cardiac and respiratory frequencies, modulation of RBF variability by fluctuations of RSNA was small at these frequencies, with values for the normalized transfer gain being approximately 0.1 at >0.5 Hz. During tail compression coherent oscillations of RSNA and RBF were found at 0.3-0.4 Hz with normalized transfer gain of 0.33 +/- 0.02. During external heat coherent oscillations of RSNA and RBF were found at both 0.2 and 0.3-0.4 Hz with normalized transfer gains of 0. 63 +/- 0.05 at 0.2 Hz and 0.53 +/- 0.04 to 0.36 +/- 0.02 at 0.3-0.4 Hz. Renal denervation eliminated the oscillations in RBF at both 0.2 and 0.3-0.4 Hz. These findings indicate that despite similar increases in total RSNA, external heat results in a greater renal vasoconstrictor response than tail compression due to the activation of a unique population of renal sympathetic nerve fibers with different frequency-response characteristics of the renal vasculature.

Unusual facial pain secondary to inferior alveolar nerve compression caused by impacted mandibular second molar

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Urvashi Sharma

2014-01-01

Full Text Available Symptoms of inferior alveolar nerve (IAN compression are reported during endodontic procedures, placement of implants, third molar surgeries, inferior alveolar nerve block injections, trauma, orthognathic injuries, ablative surgeries or use of medicaments. Presented is a rare case of a 15-year-old girl who reported severe pain in relation to an impacted permanent mandibular left second molar, the roots of which had entrapped the mandibular canal causing compression of IAN. Timely surgical intervention and sectional removal of the impacted molar is indicated to relieve the symptoms and avoid permanent damage to the nerve.

Reduction in nerve root compression by the nucleus pulposus after Feng's Spinal Manipulation☆

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Feng, Yu; Gao, Yan; Yang, Wendong; Feng, Tianyou

2013-01-01

Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng's Spinal Manipulation, hot fomentation, and bed rest (treatment group). The remaining 46 patients were treated with hot fomentation and bed rest only (control group). After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng's Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root. PMID:25206408

Sustained Local Release of NGF from a Chitosan-Sericin Composite Scaffold for Treating Chronic Nerve Compression.

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Zhang, Lei; Yang, Wen; Tao, Kaixiong; Song, Yu; Xie, Hongjian; Wang, Jian; Li, Xiaolin; Shuai, Xiaoming; Gao, Jinbo; Chang, Panpan; Wang, Guobin; Wang, Zheng; Wang, Lin

2017-02-01

Chronic nerve compression (CNC), a common form of peripheral nerve injury, always leads to chronic peripheral nerve pain and dysfunction. Current available treatments for CNC are ineffective as they usually aim to alleviate symptoms at the acute phase with limited capability toward restoring injured nerve function. New approaches for effective recovery of CNC injury are highly desired. Here we report for the first time a tissue-engineered approach for the repair of CNC. A genipin cross-linked chitosan-sericin 3D scaffold for delivering nerve growth factor (NGF) was designed and fabricated. This scaffold combines the advantages of both chitosan and sericin, such as high porosity, adjustable mechanical properties and swelling ratios, the ability of supporting Schwann cells growth, and improving nerve regeneration. The degradation products of the composite scaffold upregulate the mRNA levels of the genes important for facilitating nerve function recovery, including glial-derived neurotrophic factor (GDNF), early growth response 2 (EGR2), and neural cell adhesion molecule (NCAM) in Schwann cells, while down-regulating two inflammatory genes' mRNA levels in macrophages, tumor necrosis factor alpha (TNF-α), and interleukin-1 beta (IL-1β). Importantly, our tissue-engineered strategy achieves significant nerve functional recovery in a preclinical CNC animal model by decreasing neuralgia, improving nerve conduction velocity (NCV), accelerating microstructure restoration, and attenuating gastrocnemius muscles dystrophy. Together, this work suggests a promising clinical alternative for treating chronic peripheral nerve compression injury.

Venous compressions of the nerves in the lower limbs.

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Artico, M; Stevanato, G; Ionta, B; Cesaroni, A; Bianchi, E; Morselli, C; Grippaudo, F R

2012-06-01

The lower limbs are frequently involved in neurovascular compression syndromes, owing to their anatomical, vascular and muscular characteristics and to the orthostatic position. These syndromes were identified by exclusion, using neuroimaging techniques and treated by microsurgical techniques. Eight patients with a neurovascular compression syndrome due to venous vascular lesions in the lower limbs (popliteal fossa, proximal and medial third of the inferior limb, tarsal tunnel) were selected. The symptomatology was characterized by pain, Tinel's sign, hyperalgesia, allodynia, numbness along the nerve course and foot weakness: all were exacerbated by the standing position, thus suggesting a neurovascular compression syndrome. Diagnostic tools comprised Doppler ultrasonography, Electromyography, CT 3D and MRI. Treatment consisted of microsurgery with neurovascular dissection. Following surgical treatment, rapid pain relief and a partial recovery of neurological deficits (including the ability to walk) was observed within 8-10 months. An early diagnosis of NCS using various neuroimaging techniques and prompt treatment may improve the response to surgical therapy. The aim of the case studies described is to improve understanding of these pathologies thus enabling correct clinical decisions.

Ptosis as partial oculomotor nerve palsy due to compression by infundibular dilatation of posterior communicating artery, visualized with three-dimensional computer graphics: case report.

Science.gov (United States)

Fukushima, Yuta; Imai, Hideaki; Yoshino, Masanori; Kin, Taichi; Takasago, Megumi; Saito, Kuniaki; Nakatomi, Hirofumi; Saito, Nobuhito

2014-01-01

Oculomotor nerve palsy (ONP) due to internal carotid-posterior communicating artery (PcomA) aneurysm generally manifests as partial nerve palsy including pupillary dysfunction. In contrast, infundibular dilatation (ID) of the PcomA has no pathogenic significance, and mechanical compression of the cranial nerve is extremely rare. We describe a 60-year-old woman who presented with progressive ptosis due to mechanical compression of the oculomotor nerve by an ID of the PcomA. Three-dimensional computer graphics (3DCG) accurately visualized the mechanical compression by the ID, and her ptosis was improved after clipping of the ID. ID of the PcomA may cause ONP by mechanical compression and is treatable surgically. 3DCG are effective for the diagnosis and preoperative simulation.

Neurovascular compression of cranial nerves: CT and MRI findings

International Nuclear Information System (INIS)

Almeida Llanos, Julio; Sinner, Ricardo; Nagel, Jorge

2002-01-01

Purpose: The compression of a nervous structure by an aberrant vessel may be asymptomatic or produce an important symptoms, in these cases CT and MRI show relevant information. Materials and Methods: Between January 1998 and March 2001, we studied 27 patients: 8 with trigeminal neuralgia, 7 with hemi facial spasm, 4 vertigo and tinnitus, 2 hemianopsia, 1 with neuralgia of the amygdalin fossa, 1 with bitonal voice, 1 with tongue deviation with fascicular movements, 2 essential hypertension and 1 with severe headache. All of them had a neurologic evaluation from 2 specialists and 2 neuro radiologists interpreted the results. Results: The CT and RMI images with special sequences allowed to prove the compression of the entry segments of the V, VII, IX, X and XII cranial nerves, of the optic chiasma and the ventrolateral aspect of the medulla oblongata in close relation with the vasopressor centre. Also they demonstrate a rare vessel in the Silvio aqueduct avoiding the normal flow of the CSF. Of the total of patients that were studied, 37% had surgical confirmation. Conclusion: CT and RMI are sensitive and specific methods for the detection of vascular compressions of nervous structures. (author)

Straightening the trigeminal nerve axis by complete dissection of arachnoidal adhesion and its neuroendoscopic confirmation for trigeminal neuralgia without neurovascular compression

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Mami Ishikawa, MD, PhD

2017-12-01

Conclusions: Straightening the trigeminal nerve axis by complete dissection of the arachnoidal adhesion around the trigeminal nerve was effective for typical trigeminal neuralgia without neurovascular compression.

Correlation of MR tomographic findings and microvascular decompression treatment of the neurovascular compressions of the cranial nerves

International Nuclear Information System (INIS)

Liu Zengsheng; Chen Xiangmin; Sun Yiyan; Fang Ming; Wang Ping; Guan Yong; Sun Miao

2010-01-01

Objective: To explore the correlation of the operation effects of the miorovascular decompression (MVD) and the findings on magnetic resonance tomographie angiography (MRTA) in patients of neurovascular compression of the cranial nerves. Methods: Two hundred and twenty three patients treated with the microvascular decompression were analyzed retrospectively. They were grouped and graded according to the vessel compression on the cranial nerves. The compression were grouped as none, moderate and severe, and the operation effects were graded as I (complete relief), II (partial relief) and III ( no relief). The operation effects grades were correlated according to the compression groups by Kruskal-Wallis test and the operation effects between each two of the groups were compared using Nemenyi test. P 2 =16.84 and P<0.05. The mean rank of the non-compression, the moderate and the severe group was 134.21,102.37 and 110.4, respectively. The difference of the mean ranks between the non-compression group and the moderate group was 31.84, and between the non-compression and the severe group was 24.17, respectively, where P<0.05 both. Conclusions: There was close relationship between the findings on magnetic resonance tomographic angiography and the operation effects of the MVD. The operation effects of patients with moderate and severe vessel compression were much better than the non-compression group. MRTA is helpful for MVD surgical indication and its prognosis. (authors)

Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: Part 2. Upper extremity

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Kim, Sungjun [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Hanyang University, Kuri Hospital, Department of Diagnostic Radiology, College of Medicine, Kuri City, Kyunggi-do (Korea); Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Kim, Seung Min [Yonsei University, Department of Neurology, College of Medicine, Seoul (Korea); Suh, Jin-Suck [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Yonsei University, Research Institute of Radiological Science, College of Medicine, Seoul (Korea)

2007-02-15

The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions, but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the upper extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the upper extremity are as follows: the brachial plexus of the thoracic outlet; axillary nerve of the quadrilateral space; radial nerve of the radial tunnel; ulnar nerve of the cubital tunnel and Guyon's canal; median nerve of the pronator syndrome, anterior interosseous nerve syndrome, and carpal tunnel syndrome. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: Part 2. Upper extremity

International Nuclear Information System (INIS)

Kim, Sungjun; Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah; Kim, Seung Min; Suh, Jin-Suck

2007-01-01

The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions, but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the upper extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the upper extremity are as follows: the brachial plexus of the thoracic outlet; axillary nerve of the quadrilateral space; radial nerve of the radial tunnel; ulnar nerve of the cubital tunnel and Guyon's canal; median nerve of the pronator syndrome, anterior interosseous nerve syndrome, and carpal tunnel syndrome. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: part 1. Overview and lower extremity

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Kim, Sungjun [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Hanyang University, Kuri Hospital, Department of Diagnostic Radiology, College of Medicine, Kuri City, Kyunggi-do (Korea); Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Kim, Seung Min [Yonsei University, Department of Neurology, College of Medicine, Seoul (Korea); Suh, Jin-Suck [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Yonsei University, Research Institute of Radiological Science, College of Medicine, Seoul (Korea)

2007-01-15

The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the general concepts that should be known to evaluate the entrapment and compressive neuropathy in MR imaging. We also review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the lower extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the lower extremity are as follows: sciatic nerve around the piriformis muscle; tibial nerve at the popliteal fossa and tarsal tunnel, common peroneal nerve around the fibular neck, and digital nerve near the metatarsal head. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: part 1. Overview and lower extremity

International Nuclear Information System (INIS)

Kim, Sungjun; Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah; Kim, Seung Min; Suh, Jin-Suck

2007-01-01

The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the general concepts that should be known to evaluate the entrapment and compressive neuropathy in MR imaging. We also review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the lower extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the lower extremity are as follows: sciatic nerve around the piriformis muscle; tibial nerve at the popliteal fossa and tarsal tunnel, common peroneal nerve around the fibular neck, and digital nerve near the metatarsal head. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

Optic Nerve Atrophy Due to Long-Standing Compression by Planum Sphenoidale Meningioma.

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Di Somma, Alberto; Kaen, Ariel Matias; Cárdenas Ruiz-Valdepeñas, Eugenio; Cavallo, Luigi Maria

2018-05-01

In this study we report an uncommon endoscopic endonasal image of an atrophic optic nerve as seen after surgical removal of a suprasellar meningioma. The peculiarity of this case is the long-lasting underestimated ocular symptomatology of the patient who reported a 15-year history of impairment of vision on her left eye. A 51-year-old woman was admitted to our hospital complaining of a 15-year history of impairment of vision on her left eye. After making serendipitously the diagnosis of a suprasellar mass, we performed endoscopic endonasal surgery. The tumor was reached from below and removed safely, without manipulation of the optic pathways. At the end of tumor removal, the impressive left optic nerve atrophy due to enduring local tumor compression was visualized. To the best of our knowledge, no endoscopic endonasal image with such features has been provided in the pertinent literature. Possibly, this contribution will help identify damaged optic nerves during endoscopic endonasal surgery. Copyright © 2018 Elsevier Inc. All rights reserved.

Traumatic and compressive pathology of the peripheral nerves: value of the MRI; Patologia traumatica y compresiva de los nervios perifericos: valor de la RM

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Sanchez, M. L.; Romero, J.; Hernandez, L.; Miguel, E. de [Hospital General Universitario Gregorio Maranon. Madrid (Spain)

2000-07-01

Evaluate the usefulness of the magnetic resonance (MRI) in the diagnosis of traumatic and compressive pathology of the peripheral nerves and analyze the etiology of the lesions and their severity. 25 MRI in patients with compressive and traumatic lesions of the peripheral nerves are analyzed. They were studied with MRI (1,5T) using T1 weighted spin-echo (SE), T2 gradient echo (GE) and STIR sequences. The morphological and nerve signal alterations make it possible to locate the lesion site and to assess the course of the lesion with successive studies. In our series, the most frequent cause of compressive pathology is fibrosis. Brachial plexus root avulsion is the most frequent finding in traumatic lesions. The MTI capacity for multiplanar study and its high resolution make it possible for us to detect small lesions in the peripheral nerves and to plan the best treatment. (Author) 17 refs.

Achillea mellifolium ethanolic extract Protective effects on ventral horn of the spinal cord alpha motoneurons degeneration after sciatic nerve compression in rats

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Ali Shahraki

2015-12-01

Full Text Available Background and Aim: There are several reports regarding anti-inflammatory and tissue repair properties of the plant Achillea, but neuroprotective role of ethanolic extract of Achillea millefolium has not been studied after peripheral nerve injury. Therefore, the purpose of the present study was to assess neuroprotective effects .of Achillea millefolium ethanolic extract on the spinal cord alpha motor neuons after sciatic nerve compression in male rats. Materials and Methods: In this experimental study 30 male Wistar rats each weighing 200-250g were chosen and were randomly divided into 5 equal groups including control, compressed, and three compressed groups plus intraperitoneal injection of Achillea millefolium ethanolic extract with the concentration of 50, 75, and 100 mg/kg; once a week for three weeks. . Sciatic nerve compression in these four groups . was done using hematostatic forceps for 60 seconds. After 28 days, L4, L5,S1, and S3 of the spinal cord were sampled using perfusion method. Statistical analysis of the obtained data was done by means of one-way Anova  and Tukey post- hoc test using SPSS( version 19 at the significant level of P<0.05. Results: It was found that α-motor neurons density in the compression group (666.6±39.17 significantly decreased compared to the control group (1754±34.22 ;P <0.001. Neural density in the groups treated with ethanolic extract, i.e. 50 mg/kg .,75 mg/kg, .and.100 mg/kg was 1236±69.72.,.1444.3±39.17,.and 1546.3±57.39  respectively ;which showed a significant increase compared to the compression group (P<0.01. Conclusion: Ethanolic extract of Achillea millefolium had a neuroprotective effect after sciatic nerve compression. Presumably, this is due to antioxidant and anti-inflammatory compounds in the plant.

Investigation into Regeneration Mechanism of Hydroalcoholic Lavender (Lavandula officianalis Extract through the Evaluation of NT3 Gene Expression after Sciatic Nerve Compression in Rats

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Fereshteh Naderi Allaf

2017-05-01

Full Text Available Abstract Background: Retrograde transport to the alpha motoneurons causes spinal degeneration. The neurotrophic factor (NT3 increases the number of myelinated axons in the dorsal root, leads to differentiation and survival of sensory neurons, parasympathetic motoneurons and prevents cell death. Lavender is a plant in the family Lamiaceae which is reported to have antioxidant, antispasmodic, diuretic, anti-asthmatic, refrigerant, and antipyretic effects. This study examined NT3 gene expression changes after sciatic nerve compression in rats, in the presence of Lavandula officinalis extract. Materials and Methods: Lavender Soxhlet hydroalcoholic extraction was prepared. 36 male Wistar rats were randomly divided into 3 groups including control, compression and treatment (compression group + hydroalcoholic extract of Lavender injections 75mg/kg groups. In controls the muscle was opened without damage to gain access to the sciatic nerve. In compression and treatment groups, the sciatic nerve (right leg was compressed. The extract was injected intraperitoneally in two occasions. A biopsy was taken from the spinal cord segments L4-L6 on day 28, total RNA was extracted and cDNA was synthesized and NT3 gene expression changes were analyzed by ANOVA test by using SPSS software. Results: The results showed that NT3 gene expression had a significant reduction in compression group compared to the control group (p<0.001 and it had a significant increase in treatment group compared with the compression group (p<0.001. Conclusion: A significant increase in gene expression shows that Lavandula officinalis hydroalcoholic extract improves nerve regeneration via NT3 gene expression.

Quantitative assessment of integrated phrenic nerve activity.

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Nichols, Nicole L; Mitchell, Gordon S

2016-06-01

Integrated electrical activity in the phrenic nerve is commonly used to assess within-animal changes in phrenic motor output. Because of concerns regarding the consistency of nerve recordings, activity is most often expressed as a percent change from baseline values. However, absolute values of nerve activity are necessary to assess the impact of neural injury or disease on phrenic motor output. To date, no systematic evaluations of the repeatability/reliability have been made among animals when phrenic recordings are performed by an experienced investigator using standardized methods. We performed a meta-analysis of studies reporting integrated phrenic nerve activity in many rat groups by the same experienced investigator; comparisons were made during baseline and maximal chemoreceptor stimulation in 14 wild-type Harlan and 14 Taconic Sprague Dawley groups, and in 3 pre-symptomatic and 11 end-stage SOD1(G93A) Taconic rat groups (an ALS model). Meta-analysis results indicate: (1) consistent measurements of integrated phrenic activity in each sub-strain of wild-type rats; (2) with bilateral nerve recordings, left-to-right integrated phrenic activity ratios are ∼1.0; and (3) consistently reduced activity in end-stage SOD1(G93A) rats. Thus, with appropriate precautions, integrated phrenic nerve activity enables robust, quantitative comparisons among nerves or experimental groups, including differences caused by neuromuscular disease. Copyright © 2015 Elsevier B.V. All rights reserved.

Femoral nerve compression syndrome with paresis of the quadriceps muscle caused by radiotherapy of malignant tumours. A report of four cases

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Laurent, L E [Orthopaedic Hospital of the Invalid Foundation, Helsinki, Finland

1975-01-01

Four patients showed signs of femoral nerve compression with subsequent paresis of the quadriceps muscle, after radiation therapy of malignant tumours. The compression was caused by scar tissue due to radiation treatment of the inguinal region. The first symptom was radiating pain in the front of the thigh and lower leg which appeared 12-16 months after X-ray treatment. A decrease in the strength of quadriceps muscle occurred some months later. In one case the femoral nerve was decompressed, another patient was treated by an intradural phenolglycerin injection and one patient was treated with cortisone and oxiphenbutanzone. In these cases the pain decreased considerably, but in one case only the paresis of the quadriceps muscle improved after treatment.

Cranial nerve vascular compression syndromes of the trigeminal, facial and vago-glossopharyngeal nerves: comparative anatomical study of the central myelin portion and transitional zone; correlations with incidences of corresponding hyperactive dysfunctional syndromes.

Science.gov (United States)

Guclu, Bulent; Sindou, Marc; Meyronet, David; Streichenberger, Nathalie; Simon, Emile; Mertens, Patrick

2011-12-01

The aim of this study was to evaluate the anatomy of the central myelin portion and the central myelin-peripheral myelin transitional zone of the trigeminal, facial, glossopharyngeal and vagus nerves from fresh cadavers. The aim was also to investigate the relationship between the length and volume of the central myelin portion of these nerves with the incidences of the corresponding cranial dysfunctional syndromes caused by their compression to provide some more insights for a better understanding of mechanisms. The trigeminal, facial, glossopharyngeal and vagus nerves from six fresh cadavers were examined. The length of these nerves from the brainstem to the foramen that they exit were measured. Longitudinal sections were stained and photographed to make measurements. The diameters of the nerves where they exit/enter from/to brainstem, the diameters where the transitional zone begins, the distances to the most distal part of transitional zone from brainstem and depths of the transitional zones were measured. Most importantly, the volume of the central myelin portion of the nerves was calculated. Correlation between length and volume of the central myelin portion of these nerves and the incidences of the corresponding hyperactive dysfunctional syndromes as reported in the literature were studied. The distance of the most distal part of the transitional zone from the brainstem was 4.19  ±  0.81 mm for the trigeminal nerve, 2.86  ±  1.19 mm for the facial nerve, 1.51  ±  0.39 mm for the glossopharyngeal nerve, and 1.63  ±  1.15 mm for the vagus nerve. The volume of central myelin portion was 24.54  ±  9.82 mm(3) in trigeminal nerve; 4.43  ±  2.55 mm(3) in facial nerve; 1.55  ±  1.08 mm(3) in glossopharyngeal nerve; 2.56  ±  1.32 mm(3) in vagus nerve. Correlations (p  nerves and incidences of the corresponding diseases. At present it is rather well-established that primary trigeminal neuralgia, hemifacial spasm and vago

Tractography of lumbar nerve roots: initial results

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Balbi, Vincent; Budzik, Jean-Francois; Thuc, Vianney le; Cotten, Anne [Hopital Roger Salengro, Service de Radiologie et d' Imagerie musculo-squelettique, Lille Cedex (France); Duhamel, Alain [Universite de Lille 2, UDSL, Lille (France); Bera-Louville, Anne [Service de Rhumatologie, Hopital Roger Salengro, Lille (France)

2011-06-15

The aims of this preliminary study were to demonstrate the feasibility of in vivo diffusion tensor imaging (DTI) and fibre tracking (FT) of the lumbar nerve roots, and to assess potential differences in the DTI parameters of the lumbar nerves between healthy volunteers and patients suffering from disc herniation. Nineteen patients with unilateral sciatica related to posterolateral or foraminal disc herniation and 19 healthy volunteers were enrolled in this study. DTI with tractography of the L5 or S1 nerves was performed. Mean fractional anisotropy (FA) and mean diffusivity (MD) values were calculated from tractography images. FA and MD values could be obtained from DTI-FT images in all controls and patients. The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (p=0.0001) and of the nerve roots of volunteers (p=0.0001). MD was significantly higher in compressed nerve roots than in the contralateral nerve root (p=0.0002) and in the nerve roots of volunteers (p=0.04). DTI with tractography of the lumbar nerves is possible. Significant changes in diffusion parameters were found in the compressed lumbar nerves. (orig.)

Tractography of lumbar nerve roots: initial results

International Nuclear Information System (INIS)

Balbi, Vincent; Budzik, Jean-Francois; Thuc, Vianney le; Cotten, Anne; Duhamel, Alain; Bera-Louville, Anne

2011-01-01

The aims of this preliminary study were to demonstrate the feasibility of in vivo diffusion tensor imaging (DTI) and fibre tracking (FT) of the lumbar nerve roots, and to assess potential differences in the DTI parameters of the lumbar nerves between healthy volunteers and patients suffering from disc herniation. Nineteen patients with unilateral sciatica related to posterolateral or foraminal disc herniation and 19 healthy volunteers were enrolled in this study. DTI with tractography of the L5 or S1 nerves was performed. Mean fractional anisotropy (FA) and mean diffusivity (MD) values were calculated from tractography images. FA and MD values could be obtained from DTI-FT images in all controls and patients. The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (p=0.0001) and of the nerve roots of volunteers (p=0.0001). MD was significantly higher in compressed nerve roots than in the contralateral nerve root (p=0.0002) and in the nerve roots of volunteers (p=0.04). DTI with tractography of the lumbar nerves is possible. Significant changes in diffusion parameters were found in the compressed lumbar nerves. (orig.)

Nerve-muscle activation by rotating permanent magnet configurations.

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Watterson, Peter A; Nicholson, Graham M

2016-04-01

The standard method of magnetic nerve activation using pulses of high current in coils has drawbacks of high cost, high electrical power (of order 1 kW), and limited repetition rate without liquid cooling. Here we report a new technique for nerve activation using high speed rotation of permanent magnet configurations, generating a sustained sinusoidal electric field using very low power (of order 10 W). A high ratio of the electric field gradient divided by frequency is shown to be the key indicator for nerve activation at high frequencies. Activation of the cane toad sciatic nerve and attached gastrocnemius muscle was observed at frequencies as low as 180 Hz for activation of the muscle directly and 230 Hz for curved nerves, but probably not in straight sections of nerve. These results, employing the first prototype device, suggest the opportunity for a new class of small low-cost magnetic nerve and/or muscle stimulators. Conventional pulsed current systems for magnetic neurostimulation are large and expensive and have limited repetition rate because of overheating. Here we report a new technique for nerve activation, namely high-speed rotation of a configuration of permanent magnets. Analytical solutions of the cable equation are derived for the oscillating electric field generated, which has amplitude proportional to the rotation speed. The prototype device built comprised a configuration of two cylindrical magnets with antiparallel magnetisations, made to rotate by interaction between the magnets' own magnetic field and three-phase currents in coils mounted on one side of the device. The electric field in a rectangular bath placed on top of the device was both numerically evaluated and measured. The ratio of the electric field gradient on frequency was approximately 1 V m(-2) Hz(-1) near the device. An exploratory series of physiological tests was conducted on the sciatic nerve and attached gastrocnemius muscle of the cane toad (Bufo marinus). Activation was

Optic nerve compression as a late complication of a hydrogel explant with silicone encircling band.

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Crama, Niels; Kluijtmans, Leo; Klevering, B Jeroen

2018-06-01

To present a complication of compressive optic neuropathy caused by a swollen hydrogel explant and posteriorly displaced silicone encircling band. A 72-year-old female patient presented with progressive visual loss and a tilted optic disc. Her medical history included a retinal detachment in 1993 that was treated with a hydrogel explant under a solid silicone encircling band. Visual acuity had decreased from 6/10 to 6/20 and perimetry showed a scotoma in the temporal superior quadrant. On Magnetic Resonance Imaging (MRI), compression of the optic nerve by a displaced silicone encircling band inferior nasally in combination with a swollen episcleral hydrogel explant was observed. Surgical removal of the hydrogel explant and silicone encircling band was uneventful and resulted in improvement of visual acuity and visual field loss. This is the first report on compressive optic neuropathy caused by swelling of a hydrogel explant resulting in a dislocated silicone encircling band. The loss of visual function resolved upon removal of the explant and encircling band.

Do L5 and s1 nerve root compressions produce radicular pain in a dermatomal pattern?

Science.gov (United States)

Taylor, Christopher S; Coxon, Andrew J; Watson, Paul C; Greenough, Charles G

2013-05-20

Observational case series. To compare the pattern of distribution of radicular pain with published dermatome charts. Dermatomal charts vary and previous studies have demonstrated significant individual subject variation. Patients with radiologically and surgically proven nerve root compression (NRC) caused by prolapsed intervertebral disc completed computerized diagrams of the distribution of pain and pins and needles. Ninety-eight patients had L5 compressions and 83 had S1 compressions. The distribution of pain and pins and needles did not correspond well with dermatomal patterns. Of those patients with L5 NRC, only 22 (22.4%) recorded any hits on the L5 dermatome on the front, and only 60 (61.2%) on the back with only 13 (13.3%) on both. Only 1 (1.0%) patient placed more than 50% of their hits within the L5 dermatome. Of those patients with S1 NRC, only 3 (3.6%) recorded any hits on the S1 dermatome on the front, and only 64 (77.1%) on the back with only 15 (18.1%) on both. No patients placed more than 50% of their hits within the S1 dermatome. Regarding pins and needles, 27 (29.7%) patients with L5 NRC recorded hits on the front alone, 27 (29.7%) on the back alone, and 14 (15.4%) on both. Nineteen (20.9%) recorded more than 50% of hits within the L5 dermatome. Three (3.6%) patients with S1 NRC recorded hits on the front alone, 44 (53.0%) on the back alone, and 18 (21.7%) on both. Twelve (14.5%) recorded more than 50% of hits within the S1 dermatome. Patient report is an unreliable method of identifying the anatomical source of pain or paresthesia caused by nerve root compression. 4.

Diffusion tensor imaging with quantitative evaluation and fiber tractography of lumbar nerve roots in sciatica.

Science.gov (United States)

Shi, Yin; Zong, Min; Xu, Xiaoquan; Zou, Yuefen; Feng, Yang; Liu, Wei; Wang, Chuanbing; Wang, Dehang

2015-04-01

To quantitatively evaluate nerve roots by measuring fractional anisotropy (FA) values in healthy volunteers and sciatica patients, visualize nerve roots by tractography, and compare the diagnostic efficacy between conventional magnetic resonance imaging (MRI) and DTI. Seventy-five sciatica patients and thirty-six healthy volunteers underwent MR imaging using DTI. FA values for L5-S1 lumbar nerve roots were calculated at three levels from DTI images. Tractography was performed on L3-S1 nerve roots. ROC analysis was performed for FA values. The lumbar nerve roots were visualized and FA values were calculated in all subjects. FA values decreased in compressed nerve roots and declined from proximal to distal along the compressed nerve tracts. Mean FA values were more sensitive and specific than MR imaging for differentiating compressed nerve roots, especially in the far lateral zone at distal nerves. DTI can quantitatively evaluate compressed nerve roots, and DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and localization of probable nerve compression. DTI has great potential utility for evaluating lumbar nerve compression in sciatica. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Diffusion tensor imaging with quantitative evaluation and fiber tractography of lumbar nerve roots in sciatica

International Nuclear Information System (INIS)

Shi, Yin; Zong, Min; Xu, Xiaoquan; Zou, Yuefen; Feng, Yang; Liu, Wei; Wang, Chuanbing; Wang, Dehang

2015-01-01

Highlights: •In the present study, we first elected ROIs corresponding to the proximal, medial, and distal levels of the lumbar foraminal zone. •The ROC analysis for FA values of distal nerves indicated a high level of reliability in the diagnosis of sciatica. •The declining trend of FA values from proximal to distal along the nerve tract may correlate with the disparity of axonal regeneration at different levels. •DTI is able to quantitatively evaluate compressed nerve roots and has a higher sensitivity and specificity for diagnosing sciatica than conventional MR imaging. •DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and probable localization of nerve compression. -- Abstract: Objective: To quantitatively evaluate nerve roots by measuring fractional anisotropy (FA) values in healthy volunteers and sciatica patients, visualize nerve roots by tractography, and compare the diagnostic efficacy between conventional magnetic resonance imaging (MRI) and DTI. Materials and methods: Seventy-five sciatica patients and thirty-six healthy volunteers underwent MR imaging using DTI. FA values for L5–S1 lumbar nerve roots were calculated at three levels from DTI images. Tractography was performed on L3–S1 nerve roots. ROC analysis was performed for FA values. Results: The lumbar nerve roots were visualized and FA values were calculated in all subjects. FA values decreased in compressed nerve roots and declined from proximal to distal along the compressed nerve tracts. Mean FA values were more sensitive and specific than MR imaging for differentiating compressed nerve roots, especially in the far lateral zone at distal nerves. Conclusions: DTI can quantitatively evaluate compressed nerve roots, and DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and localization of probable nerve compression. DTI has great potential utility for evaluating lumbar nerve compression in sciatica

Diffusion tensor imaging with quantitative evaluation and fiber tractography of lumbar nerve roots in sciatica

Energy Technology Data Exchange (ETDEWEB)

Shi, Yin; Zong, Min; Xu, Xiaoquan; Zou, Yuefen; Feng, Yang; Liu, Wei; Wang, Chuanbing; Wang, Dehang, E-mail: njmu_wangdehang@126.com

2015-04-15

Highlights: •In the present study, we first elected ROIs corresponding to the proximal, medial, and distal levels of the lumbar foraminal zone. •The ROC analysis for FA values of distal nerves indicated a high level of reliability in the diagnosis of sciatica. •The declining trend of FA values from proximal to distal along the nerve tract may correlate with the disparity of axonal regeneration at different levels. •DTI is able to quantitatively evaluate compressed nerve roots and has a higher sensitivity and specificity for diagnosing sciatica than conventional MR imaging. •DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and probable localization of nerve compression. -- Abstract: Objective: To quantitatively evaluate nerve roots by measuring fractional anisotropy (FA) values in healthy volunteers and sciatica patients, visualize nerve roots by tractography, and compare the diagnostic efficacy between conventional magnetic resonance imaging (MRI) and DTI. Materials and methods: Seventy-five sciatica patients and thirty-six healthy volunteers underwent MR imaging using DTI. FA values for L5–S1 lumbar nerve roots were calculated at three levels from DTI images. Tractography was performed on L3–S1 nerve roots. ROC analysis was performed for FA values. Results: The lumbar nerve roots were visualized and FA values were calculated in all subjects. FA values decreased in compressed nerve roots and declined from proximal to distal along the compressed nerve tracts. Mean FA values were more sensitive and specific than MR imaging for differentiating compressed nerve roots, especially in the far lateral zone at distal nerves. Conclusions: DTI can quantitatively evaluate compressed nerve roots, and DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and localization of probable nerve compression. DTI has great potential utility for evaluating lumbar nerve compression in sciatica.

Músculo pronador redondo: variações anatômicas e predisposição para a compressão do nervo mediano Pronator teres muscle: anatomical variations and predisposition for the compression of the median nerve

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Vilma Clóris de Carvalho

2002-05-01

Full Text Available O nervo mediano pode ser comprimido em nível de músculo pronador redondo (MPR, resultando na síndrome do pronador redondo. Objetivou-se analisar a constituição do MPR e sua relação com o nervo mediano na dissecação de 100 membros superiores humanos, oriundos de laboratórios de anatomia. Em 72% dos casos, o nervo mediano passou entre as cabeças umeral e ulnar do MPR. Em 15% a cabeça ulnar esteve ausente, com o nervo mediano passando posteriormente a cabeça umeral ou através dela. Em 9% a cabeça ulnar se fez representar por um feixe fibroso. Em 2% o nervo mediano passou através da cabeça ulnar e em 2% através da cabeça umeral, mesmo na presença da cabeça ulnar. Os dados sugerem que as variações na relação músculo/nervo representam fatores potenciais para a compressão do nervo mediano, por tornarem mais restrita a passagem desse nervo no antebraço.The median nerve can be compressed at the level of pronator teres muscle (PTM, resulting in the pronator teres syndrome. This work aim was to analyze the PTM and its relationship with the median nerve. In order to do so, we have dissected 100 human upper limbs from anatomy laboratories. In 72% of the cases, the median nerve passed between the umeral and ulnar heads of PTM. In 15% of the cases, the ulnar head was absent, with the median nerve passing behind the umeral head or through it. In 9%, a fibrous bundle represented the ulnar head. In 2%, the median nerve passed through the ulnar head and in 2% through the umeral head, even in the presence of the ulnar head. The data suggest that the variations in the relationship muscle/nerve represent potential factors for the median nerve compression, for they make the passage for this nerve in the forearm even narrower.

Atrophic changes in the trigeminal nerves of patients with trigeminal neuralgia due to neurovascular compression and their association with the severity of compression and clinical outcomes.

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Leal, Paulo Roberto Lacerda; Barbier, Charlotte; Hermier, Marc; Souza, Miguel Angelo; Cristino-Filho, Gerardo; Sindou, Marc

2014-06-01

The aim of this study was to prospectively evaluate atrophic changes in trigeminal nerves (TGNs) using measurements of volume (V) and cross-sectional area (CSA) from high-resolution 3-T MR images obtained in patients with unilateral trigeminal neuralgia (TN), and to correlate these data with patient and neurovascular compression (NVC) characteristics and with clinical outcomes. Anatomical TGN parameters (V and CSA) were obtained in 50 patients (30 women and 20 men; mean age 56.42 years, range 22-79 years) with classic TN before treatment with microvascular decompression (MVD). Parameters were compared between the symptomatic (ipsilateralTN) and asymptomatic (contralateralTN) sides of the face. Twenty normal control subjects were also included. Two independent observers blinded to the side of pain separately analyzed the images. Measurements of V (from the pons to the entrance of the nerve into Meckel's cave) and CSA (at 5 mm from the entry of the TGN into the pons) for each TGN were performed using imaging software and axial and coronal projections, respectively. These data were correlated with patient characteristics (age, duration of symptoms before MVD, side of pain, sex, and area of pain distribution), NVC characteristics (type of vessel involved in NVC, location of compression along the nerve, site of compression around the circumference of the root, and degree of compression), and clinical outcomes at the 2-year follow-up after surgery. Comparisons were made using Bonferroni's test. Interobserver variability was assessed using the Pearson correlation coefficient. The mean V of the TGN on the ipsilateralTN (60.35 ± 21.74 mm(3)) was significantly smaller (p controls (78.62 ± 24.62 mm(3) and 89.09 ± 14.72 mm(3), respectively). The mean CSA of the TGN on the ipsilateralTN (4.17 ± 1.74 mm(2)) was significantly smaller than those for the contralateralTN and controls (5.41 ± 1.89 mm(2) and 5.64 ± 0.85 mm(2), respectively). The ipsilateralTN with NVC Grade III

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves

DEFF Research Database (Denmark)

Barghash, Ziad; Larsen, Jytte Overgaard; Al-Bishri, Awad

2013-01-01

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod...... for 30 s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both...... in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed...

MRI analysis of vascular compressive trigeminal neuralgia

International Nuclear Information System (INIS)

Tang Ling; Chai Weimin; Song Qi; Ling Huawei; Miao Fei; Chen Kemin

2006-01-01

Objective: To analyze the offending vessels of vascular compressive trigeminal neuralgia by magnetic resonance tomographic angiography (MRTA). Methods: MRTA images of 235 asymptomatic trigeminal nerves and 147 symptomatic trigeminal nerves were analyzed by two radiologists who were blinded to the clinical findings. Judgment was made on if there were some vessels close to the trigeminal nerve. The diameter of the offending vessel, the distance from the offending vessel's contact point to the pons and the direction of the vessel toward the nerve were also recorded at the same time. Group t-test and Chi-Square test were used for statistics. Results: Two hundred and forty-two trigeminal nerves of all 382 nerves can be detected offending vessels on MRTA images, 111 of 242 trigeminal nerves were asymptomatic, the rest 131 were symptomatic. Statistical analysis indicated that the distance from the offending vessel's contact point to the pons in symptomatic group (the median is 2 mm) was shorter than that in the asymptomatic group (the median is 4 mm) (P<0.01). In 89.3% cases (117/131) of the symptomatic group the angle between the vessel and the nerve is larger than 45 degree, but only in 67.6% cases (75/111) in the asymptomatic group the angle is larger than 45 degree. That means significant difference is between the two groups (P<0.01). Vessel-nerve compression can be seen in 1 case of asymptomatic group (0.4%, 1/235) and 45 eases in symptomatic group (30.6%, 45/147). The vessel-nerve compression rate of the symptomatic group was much higher than that of the asymptomatic group (P<0.01). Conclusion: MR is a useful tool to evaluate the offending vessels of vascular compressive trigeminal neuralgia. The distance from the offending vessel's contact point to the pons and the direction of the vessel toward the nerve are related to the onset of vascular compressive trigeminal neuralgia. (authors)

Vasodilative effects of prostaglandin E1 derivate on arteries of nerve roots in a canine model of a chronically compressed cauda equina

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Konno Shin-ichi

2008-04-01

Full Text Available Abstract Background Reduction of blood flow is important in the induction of neurogenic intermittent claudication (NIC in lumbar spinal canal stenosis. PGE1 improves the mean walking distance in patients with NIC type cauda equina compression. PGE1 derivate might be effective in dilating blood vessels and improving blood flow in nerve roots with chronically compressed cauda equina. The aim of this study was to assess whether PGE1 derivate has vasodilatory effects on both arteries and veins in a canine model of chronic cauda equina compression. Methods Fourteen dogs were used in this study. A plastic balloon inflated to 10 mmHg was placed under the lamina of the 7th lumbar vertebra for 1 week. OP-1206-cyclodextrin clathrate (OP-1206-CD: prostaglandin E1 derivate was administered orally. The blood vessels of the second or third sacral nerve root were identified using a specially designed surgical microscope equipped with a video camera. The diameter of the blood vessels was measured on video-recordings every 15 minutes until 90 minutes after the administration of the PGE1 derivate. Results We observed seven arteries and seven veins. The diameter and blood flow of the arteries was significantly increased compared with the veins at both 60 and 75 minutes after administration of the PGE1 derivate (p Discussion The PGE1 derivate improved blood flow in the arteries but did not induce blood stasis in the veins. Our results suggest that the PGE1 derivate might be a potential therapeutic agent, as it improved blood flow in the nerve roots in a canine model of chronic cauda equina compression.

Morphology and morphometry of the ulnar head of the pronator teres muscle in relation to median nerve compression at the proximal forearm.

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Gurses, I A; Altinel, L; Gayretli, O; Akgul, T; Uzun, I; Dikici, F

2016-12-01

The pronator syndrome is a rare compression neuropathy of the median nerve. Ulnar head of the pronator teres muscle may cause compression at proximal forearm. Detailed morphologic and morphometric studies on the anatomy of the ulnar head of pronator teres is scarce. We dissected 112 forearms of fresh cadavers. We evaluated the morphology and morphometry of the ulnar head of pronator teres muscle. The average ulnar head width was 16.3±8.2mm. The median nerve passed anterior to the ulnar head at a distance of 50.4±10.7mm from the interepicondylar line. We classified the morphology of the ulnar head into 5 types. In type 1, the ulnar head was fibromuscular in 60 forearms (53.6%). In type 2, it was muscular in 23 forearms (20.5%). In type 3, it was just a fibrotic band in 18 forearms (16.1%). In type 4, it was absent in 9 forearms (8%). In type 5, the ulnar head had two arches in 2 forearms (1.8%). In 80 forearms (71.5%: types 1, 3, and 5), the ulnar head was either fibromuscular or a fibrotic band. Although the pronator syndrome is a rare compression syndrome, the ulnar head of pronator teres is reported as the major cause of entrapment in the majority of the cases. The location of the compression of the median nerve in relation to the ulnar head of pronator teres muscle and the morphology of the ulnar head is important for open or minimally-invasive surgical treatment. Sectional study. Basic science study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Experimental chronic entrapment of the sciatic nerve in adult hamsters: an ultrastructural and morphometric study

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Prinz R.A.D.

2003-01-01

Full Text Available Entrapment neuropathy is a group of clinical disorders involving compression of a peripheral nerve and interference with nerve function mostly through traction injury. We have investigated the chronic compression of peripheral nerves as an experimental procedure for detecting changes in ultrastructural nerve morphology. Adult hamsters (Mesocricetus auratus, N = 30 were anesthetized with a 25% pentobarbital solution and received a cuff around the right sciatic nerve. Left sciatic nerves were not operated (control group. Animals survived for varying times (up to 15 weeks, after which they were sacrificed and both sciatic nerves were immediately fixed with a paraformaldehyde solution. Experimental nerves were divided into segments based upon their distance from the site of compression (proximal, entrapment and distal. Semithin and ultrathin sections were obtained and examined by light and electron microscopy. Ultrastructural changes were qualitatively described and data from semithin sections were morphometrically analyzed both in control and in compressed nerves. We observed endoneurial edema along with both perineurial and endoneurial thickening and also the existence of whorled cell-sparse structures (Renaut bodies in the subperineurial space of compressed sciatic nerves. Morphometric analyses of myelinated axons at the compression sites displayed a remarkable increase in the number of small axons (up to 60% in comparison with the control axonal number. The distal segment of compressed nerves presented a distinct decrease in axon number (up to 40% comparatively to the control group. The present experimental model of nerve entrapment in adult hamsters was shown to promote consistent histopathologic alterations analogous to those found in chronic compressive neuropathies.

Microstructural Changes in Compressed Nerve Roots Are Consistent With Clinical Symptoms and Symptom Duration in Patients With Lumbar Disc Herniation.

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Wu, Weifei; Liang, Jie; Ru, Neng; Zhou, Caisheng; Chen, Jianfeng; Wu, Yongde; Yang, Zong

2016-06-01

A prospective study. To investigate the association between microstructural nerve roots changes on diffusion tensor imaging (DTI) and clinical symptoms and their duration in patients with lumbar disc herniation. The ability to identify microstructural properties of the nervous system with DTI has been demonstrated in many studies. However, there are no data regarding the association between microstructural changes evaluated using DTI and symptoms assessed with the Oswestry Disability Index (ODI) and their duration. Forty consecutive patients with foraminal disc herniation affecting unilateral sacral 1 (S1) nerve roots were enrolled in this study. DTI with tractography was performed on the S1 nerve roots. Clinical symptoms were evaluated using an ODI questionnaire for each patient, and the duration of clinical symptoms was noted based on the earliest instance of leg pain and numbness. Mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated from tractography images. The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (P leg pain, indicating that the microstructure of the nerve root has been damaged. 3.

The Study of Effects of Aqueous and Alcoholic Extracts of Portulaca oleracea Leaves on NT3 Gene Expression in Degeneration of Alpha Neurons after Sciatic Nerve Compression in Rats

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Shokoufe Hejazi

2017-03-01

Full Text Available Abstract Background: The injuries of peripheral nervous system cause the death of a number of motor cells of the spinal cord. Neurotrophins family genes such as NT3 involve in neuronal survive after nerve injury and their expression changes after it. With due attention to the expansion of portulaca pleracea in the world study was conducted to determine the effects of alcoholic and aqueous extracts of Potulaca oleracea on the NT3 gene expression after sciatic nerve compression in rat. Materials and Methods: This study was performed on 88 male wistar rats that randomly were divided in 13 groups of 6 each. They consisted of control group, 4 compression groups (The sciatic nerve was compressed with locker pincer and 8 treatment groups: compression + treatment with dose of 75 mg/kg of alcoholic and aqueous extract of Portulaca oleracea on days 1 and 7 (never compression was done on the first day. In all groups, Total RNA was extracted from the lumbar spinal cord segment in 1, 7, 14, 28 days and cDNA was synthesized, then NT3 expression changes were compared in groups. Results: There was a significant increase in NT3 gene expression in the compression group compared to control (p<0.001. The NT3 gene expression shows significant increase (p<0.05 in the treatment groups with alcoholic extract (except 1& 28 days. Also, there was no significant difference in gene expression between treatment group with acqueous extract and compression group in 1 and 7 days. A significant decrease was seen in the treatment groups with aqueous extract of purslane compared to compression (p<0.05. The NT3 gene expression shows significant increase in the treatment groups with alcoholic extract compared to treatment groups with aqueous extract in all days (p<0.05. Conclusion: The results reveal the Portulaca oleracea leaves extracts increase the NT3 gene expression after sciatic nerve injury. This effect is more in alcoholic extract than aqueous extract.

Comparison of MR versus CT myelography and plain CT in the diagnosis of nerve compression in acute low-back pain patients

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Thornbury, J.R.; Fryback, D.G.; Turski, P.A.; Javid, M.; McDonald, J.V.; Beinlich, B.R.

1991-01-01

This paper reports on how to determine if MR could replace CT-myelography or plain CT in the diagnosis of disk-caused nerve compression in patients with acute low back pain. Ninety-five outpatients were recruited from surgical and nonsurgical clinics. Each patient underwent MR (n = 95) and either CT-myelography (n = 63) or plain Ct (n = 32). Patients were followed up for 6-12 months. Fifty-six patients underwent surgical intervention, while 39 patients were treated conservatively. Retrospective blinded readings were done by using forced choice diagnoses and probability estimates. An expert panel (neurosurgeon and neurologist) determined the true diagnosis and probability of nerve compression in each case. Diagnosis was based on all record information including surgical findings (but excluding imaging results to reduce incorporation bias). Receiver operating characteristic (ROC) analysis was performed based on the blinded reading results and panel-determined true diagnoses. Subgroup analysis also will be presented

A diagnostic study in patients with sciatica establishing the importance of localization of worsening of pain during coughing, sneezing and straining to assess nerve root compression on MRI.

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Verwoerd, Annemieke J H; Mens, Jan; El Barzouhi, Abdelilah; Peul, Wilco C; Koes, Bart W; Verhagen, Arianne P

2016-05-01

To test whether the localization of worsening of pain during coughing, sneezing and straining matters in the assessment of lumbosacral nerve root compression or disc herniation on MRI. Recently the diagnostic accuracy of history items to assess disc herniation or nerve root compression on magnetic resonance imaging (MRI) was investigated. A total of 395 adult patients with severe sciatica of 6-12 weeks duration were included in this study. The question regarding the influence of coughing, sneezing and straining on the intensity of pain could be answered on a 4 point scale: no worsening of pain, worsening of back pain, worsening of leg pain, worsening of back and leg pain. Diagnostic odds ratio's (DORs) were calculated for the various dichotomization options. The DOR changed into significant values when the answer option was more narrowed to worsening of leg pain. The highest DOR was observed for the answer option 'worsening of leg pain' with a DOR of 2.28 (95 % CI 1.28-4.04) for the presence of nerve root compression and a DOR of 2.50 (95 % CI 1.27-4.90) for the presence of a herniated disc on MRI. Worsening of leg pain during coughing, sneezing or straining has a significant diagnostic value for the presence of nerve root compression and disc herniation on MRI in patients with sciatica. This study also highlights the importance of the formulation of answer options in history taking.

Experimental study of vascularized nerve graft: evaluation of nerve regeneration using choline acetyltransferase activity.

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Iwai, M; Tamai, S; Yajima, H; Kawanishi, K

2001-01-01

A comparative study of nerve regeneration was performed on vascularized nerve graft (VNG) and free nerve graft (FNG) in Fischer strain rats. A segment of the sciatic nerve with vascular pedicle of the femoral artery and vein was harvested from syngeneic donor rat for the VNG group and the sciatic nerve in the same length without vascular pedicle was harvested for the FNG group. They were transplanted to a nerve defect in the sciatic nerve of syngeneic recipient rats. At 2, 4, 6, 8, 12, 16, and 24 weeks after operation, the sciatic nerves were biopsied and processed for evaluation of choline acetyltransferase (CAT) activity, histological studies, and measurement of wet weight of the muscle innervated by the sciatic nerve. Electrophysiological evaluation of the grafted nerve was also performed before sacrifice. The average CAT activity in the distal to the distal suture site was 383 cpm in VNG and 361 cpm in FNG at 2 weeks; 6,189 cpm in VNG and 2,264 cpm in FNG at 4 weeks; and 11,299 cpm in VNG and 9,424 cpm in FNG at 6 weeks postoperatively. The value of the VNG group was statistically higher than that of the FNG group at 4 weeks postoperatively. Electrophysiological and histological findings also suggested that nerve regeneration in the VNG group was superior to that in the FNG group during the same period. However, there was no significant difference between the two groups after 6 weeks postoperatively in any of the evaluations. The CAT measurement was useful in the experiments, because it was highly sensitive and reproducible. Copyright 2001 Wiley-Liss, Inc.

US and MR imaging of peripheral nerves in leprosy

International Nuclear Information System (INIS)

Martinoli, C.; Derchi, L.E.; Gandolfo, N.; Bertolotto, M.; Bianchi, S.; Fiallo, P.; Nunzi, E.

2000-01-01

Objective. To analyze peripheral nerves with ultrasonography (US) and magnetic resonance imaging (MR) in leprosy and assess the role of imaging in leprosy patients. Results. Leprosy nerves were classified into three groups based on imaging appearance: group I consisted of 17 normal-appearing nerves; group II, of 30 enlarged nerves with fascicular abnormalities; group III, of 11 nerves with absent fascicular structure. Group II nerves were from patients subjected to reversal reactions; 75% of patients with group III nerves had a history of erythema nodosum leprosum. Nerve compression in osteofibrous tunnels was identified in 33% of group II and 18% of group III nerves. Doppler US and MR imaging were 74% and 92% sensitive in identifying active reactions, based on detection of endoneural color flow signals, long T2 and Gd enhancement. In 64% of cases, follow-up studies showed decreased color flow and Gd uptake after steroids and decompressive surgery.Conclusions. US and MR imaging are able to detect nerves abnormalities in leprosy. Active reversal reactions are indicated by endoneural color flow signals as well as by an increased T2 signal and Gd enhancement. These signs would suggest rapid progression of nerve damage and a poor prognosis unless antireactional treatment is started. (orig.)

US and MR imaging of peripheral nerves in leprosy

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Martinoli, C. [Department of Radiology ' ' R' ' , DICMI, University of Genoa, Genoa (Italy); Cattedra di Radiologia ' ' R' ' , Universita di Genova, Largo Rosanna Benzi, 8, I-16132 Genoa (Italy); Derchi, L.E.; Gandolfo, N. [Department of Radiology ' ' R' ' , DICMI, University of Genoa, Genoa (Italy); Bertolotto, M. [Department of Radiology, University of Trieste, Strada di Fiume, I-34149 Trieste (Italy); Bianchi, S. [Division de Radiodiagnostic. Hopital Cantonal Huniversitaire, Rue Micheli du Crest, Geneva (Switzerland); Fiallo, P.; Nunzi, E. [Department of Tropical Medicine, University of Genoa, Largo Rosanna Benzi 8, I-16132 Genoa (Italy)

2000-03-30

Objective. To analyze peripheral nerves with ultrasonography (US) and magnetic resonance imaging (MR) in leprosy and assess the role of imaging in leprosy patients. Results. Leprosy nerves were classified into three groups based on imaging appearance: group I consisted of 17 normal-appearing nerves; group II, of 30 enlarged nerves with fascicular abnormalities; group III, of 11 nerves with absent fascicular structure. Group II nerves were from patients subjected to reversal reactions; 75% of patients with group III nerves had a history of erythema nodosum leprosum. Nerve compression in osteofibrous tunnels was identified in 33% of group II and 18% of group III nerves. Doppler US and MR imaging were 74% and 92% sensitive in identifying active reactions, based on detection of endoneural color flow signals, long T2 and Gd enhancement. In 64% of cases, follow-up studies showed decreased color flow and Gd uptake after steroids and decompressive surgery.Conclusions. US and MR imaging are able to detect nerves abnormalities in leprosy. Active reversal reactions are indicated by endoneural color flow signals as well as by an increased T2 signal and Gd enhancement. These signs would suggest rapid progression of nerve damage and a poor prognosis unless antireactional treatment is started. (orig.)

Optic nerve compression as a late complication of a hydrogel explant with silicone encircling band

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Niels Crama

2018-06-01

Full Text Available Purpose: To present a complication of compressive optic neuropathy caused by a swollen hydrogel explant and posteriorly displaced silicone encircling band. Observations: A 72-year-old female patient presented with progressive visual loss and a tilted optic disc. Her medical history included a retinal detachment in 1993 that was treated with a hydrogel explant under a solid silicone encircling band. Visual acuity had decreased from 6/10 to 6/20 and perimetry showed a scotoma in the temporal superior quadrant. On Magnetic Resonance Imaging (MRI, compression of the optic nerve by a displaced silicone encircling band inferior nasally in combination with a swollen episcleral hydrogel explant was observed. Surgical removal of the hydrogel explant and silicone encircling band was uneventful and resulted in improvement of visual acuity and visual field loss. Conclusions and importance: This is the first report on compressive optic neuropathy caused by swelling of a hydrogel explant resulting in a dislocated silicone encircling band. The loss of visual function resolved upon removal of the explant and encircling band. Keywords: Retinal detachment, Tilted disc, Optic neuropathy, Miragel, Explant, Encircling band

Anatomy of pudendal nerve at urogenital diaphragm--new critical site for nerve entrapment.

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Hruby, Stephan; Ebmer, Johannes; Dellon, A Lee; Aszmann, Oskar C

2005-11-01

To investigate the relations of the pudendal nerve in this complex anatomic region and determine possible entrapment sites that are accessible for surgical decompression. Entrapment neuropathies of the pudendal nerve are an uncommon and, therefore, often overlooked or misdiagnosed clinical entity. The detailed relations of this nerve as it exits the pelvis through the urogenital diaphragm and enters the mobile part of the penis have not yet been studied. Detailed anatomic dissections were performed in 10 formalin preserved hemipelves under 3.5x loupe magnification. The pudendal nerve was dissected from the entrance into the Alcock canal to the dorsum of the penis. The branching pattern of the nerve and its topographic relationship were recorded and photographs taken. The anatomic dissections revealed that the pudendal nerve passes through a tight osteofibrotic canal just distal to the urogenital diaphragm at the entrance to the base of the penis. This canal is, in part, formed by the inferior ramus of the pubic bone, the suspensory ligament of the penis, and the ischiocavernous body. In two specimens, a fusiform pseudoneuromatous thickening was found. The pudendal nerve is susceptible to compression at the passage from the Alcock canal to the dorsum of the penis. Individuals exposed to repetitive mechanical irritation in this region are especially endangered. Diabetic patients with peripheral neuropathy can have additional compression neuropathy with decreased penile sensibility and will benefit from decompression of the pudendal nerve.

Repetitive trauma and nerve compression.

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Carragee, E J; Hentz, V R

1988-01-01

Repetitive movement of the upper extremity, whether recreational or occupational, may result in various neuropathies, the prototype of which is the median nerve neuropathic in the carpal canal. The pathophysiology of this process is incompletely understood but likely involves both mechanical and ischemic features. Experimentally increased pressures within the carpal canal produced reproducible progressive neuropathy. Changes in vibratory (threshold-type) sensibility appears to be more sensitive than two-point (innervation density-type) sensibility. The specific occupational etiologies of carpal neuropathy are obscured by methodologic and sociological difficulties, but clearly some occupations have high incidences of CTS. History and physical examination are usually sufficient for the diagnosis, but diagnostic assistance when required is available through electrophysiological testing, CT scanning, and possibly MRI. Each of these tests has limitations in both sensitivity and specificity. Treatment by usual conservative means should be combined with rest from possible provocative activities. Surgical release of the carpal canal is helpful in patients failing conservative therapy. Occupational modifications are important in both treatment and prevention of median neuropathy due to repetitive trauma.

Diffusion-weighted magnetic resonance imaging of symptomatic nerve root of patients with lumbar disk herniation

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Eguchi, Yawara; Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Inoue, Gen; Takahashi, Kazuhisa [Chiba University, Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba (Japan); Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi [Chiba University Hospital, Department of Radiology, Chiba (Japan); Toyone, Tomoaki [Teikyo University Chiba Medical Center, Department of Orthopaedic Surgery, Chiba (Japan); Takaso, Masashi [Kitasato University, Department of Orthopaedic Surgery, School of Medicine, Sagamihara City, Kanagawa (Japan); Aoki, Yasuchika [Chiba Rosai Hospital, Department of Orthopedic Surgery, Ichihara, Chiba (Japan)

2011-09-15

Diffusion-weighted imaging (DWI) can provide valuable structural information that may be useful for evaluating pathological changes of the lumbar nerve root. Diffusion-weighted magnetic resonance (MR) neurography has recently been introduced as an alternative way to visualize nerves, but to date, quantitative DWI and MR neurography have not been applied to evaluate the pathology of lumbar nerve roots. Our purpose was to visualize lumbar nerve roots and to analyze their morphology by MR neurography, and to measure the apparent diffusion coefficient (ADC) of lumbar nerve roots compressed by herniated disks using 1.5-T MR imaging. Ten consecutive patients (median age, 48.0 and range, 20-72 years) with monoradicular symptoms caused by a lumbar herniated disk and 14 healthy volunteers were studied. Regions of interests were placed on the lumbar roots at dorsal root ganglia (DRG) and distal spinal nerves on DWI to quantify mean ADC values. The spinal nerve roots were also visualized by MR neurography. In the patients, mean ADC values were significantly greater in the compressed DRG and distal spinal nerves than in intact nerves. MR neurography also showed abnormalities such as nerve swelling at and below the compression in the symptomatic nerve root. Increased ADC values were considered to be because of edema and Wallerian degeneration of compressed nerve roots. DWI is a potential tool for analysis of the pathophysiology of lumbar nerve roots compressed by herniated disks. (orig.)

Diffusion-weighted magnetic resonance imaging of symptomatic nerve root of patients with lumbar disk herniation

International Nuclear Information System (INIS)

Eguchi, Yawara; Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Inoue, Gen; Takahashi, Kazuhisa; Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi; Toyone, Tomoaki; Takaso, Masashi; Aoki, Yasuchika

2011-01-01

Diffusion-weighted imaging (DWI) can provide valuable structural information that may be useful for evaluating pathological changes of the lumbar nerve root. Diffusion-weighted magnetic resonance (MR) neurography has recently been introduced as an alternative way to visualize nerves, but to date, quantitative DWI and MR neurography have not been applied to evaluate the pathology of lumbar nerve roots. Our purpose was to visualize lumbar nerve roots and to analyze their morphology by MR neurography, and to measure the apparent diffusion coefficient (ADC) of lumbar nerve roots compressed by herniated disks using 1.5-T MR imaging. Ten consecutive patients (median age, 48.0 and range, 20-72 years) with monoradicular symptoms caused by a lumbar herniated disk and 14 healthy volunteers were studied. Regions of interests were placed on the lumbar roots at dorsal root ganglia (DRG) and distal spinal nerves on DWI to quantify mean ADC values. The spinal nerve roots were also visualized by MR neurography. In the patients, mean ADC values were significantly greater in the compressed DRG and distal spinal nerves than in intact nerves. MR neurography also showed abnormalities such as nerve swelling at and below the compression in the symptomatic nerve root. Increased ADC values were considered to be because of edema and Wallerian degeneration of compressed nerve roots. DWI is a potential tool for analysis of the pathophysiology of lumbar nerve roots compressed by herniated disks. (orig.)

Handlebar palsy--a compression syndrome of the deep terminal (motor) branch of the ulnar nerve in biking.

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Capitani, Daniel; Beer, Serafin

2002-10-01

We describe 3 patients who developed a severe palsy of the intrinsic ulnar supplied hand muscles after bicycle riding. Clinically and electrophysiologically all showed an isolated lesion of the deep terminal motor branch of the ulnar nerve leaving the hypothenar muscle and the distal sensory branch intact. This type of lesion at the canal of Guyon is quite unusual, caused in the majority of cases by chronic external pressure over the ulnar palm. In earlier reports describing this lesion in bicycle riders, most patients experienced this lesion after a long distance ride. Due to the change of riding position and shape of handlebars (horn handle) in recent years, however, even a single bicycle ride may be sufficient to cause a lesion of this ulnar branch. Especially in downhill riding, a large part of the body weight is supported by the hand on the corner of the handlebar leading to a high load at Guyon's canal. As no sensory fibres are affected, the patients are not aware of the ongoing nerve compression until a severe lesion develops. Individual adaptation of the handlebar and riding position seems to be crucial for prevention of this type of nerve lesion.

MRI enhancement of the facial nerve with Gd-DTPA, 1

International Nuclear Information System (INIS)

Yanagida, Masahiro

1993-01-01

Although there have recently been numerous reports of enhanced MRI in patients with facial palsy, the mechanism of enhancement remains largely unknown. In the present study, animal models with experimentally induced facial paralysis were prepared, and the vascular permeabilities of normal and damaged facial nerves were assessed using Evans blue albumin (EBA) as a tracer. The Gd-DTPA contents in normal and compressively damaged facial nerves were also investigated. In the normal intratemporal facial nerve, EBA remained in the vessels, and did not leak into the endoneurium. In contrast, vascular permeability was very high in the epineurium and the geniculate ganglion which showed leakage of large amounts of EBA from vessels. At the site of compression in the damaged nerve, EBA leakage was also seen in the endoneurism, indicating accentuated vascular permeability. This accentuation of vascular permeability shifted toward the distal side. However, no EBA leakage was seen on the side proximal to the site of compression. Significantly higher Gd-DTPA contents were obtained in the facial nerve on the paralytic side than in that on the normal side (p<0.001). As for differences between the distal and proximal sides, the distal side had a significantly higher Gd-DTPA content (p<0.01). Assessment of vascular permeability with EBA revealed accentuated vascular permeability on the side distal to the site of compression. These results showed the presence of a blood nerve barrier (BNB) in the facial nerve. Furthermore, the present findings suggest that the enhancement of the facial nerve on the affected side is caused by BNB destruction due to nerve damage and subsequent Gd-DTPA leakage from the vessels. Furthermore, it is suggested that the facial nerve enhancement appears to occur mainly on the distal side of the damaged portion of the nerve. (author)

Perceptual consequences of disrupted auditory nerve activity.

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Zeng, Fan-Gang; Kong, Ying-Yee; Michalewski, Henry J; Starr, Arnold

2005-06-01

Perceptual consequences of disrupted auditory nerve activity were systematically studied in 21 subjects who had been clinically diagnosed with auditory neuropathy (AN), a recently defined disorder characterized by normal outer hair cell function but disrupted auditory nerve function. Neurological and electrophysical evidence suggests that disrupted auditory nerve activity is due to desynchronized or reduced neural activity or both. Psychophysical measures showed that the disrupted neural activity has minimal effects on intensity-related perception, such as loudness discrimination, pitch discrimination at high frequencies, and sound localization using interaural level differences. In contrast, the disrupted neural activity significantly impairs timing related perception, such as pitch discrimination at low frequencies, temporal integration, gap detection, temporal modulation detection, backward and forward masking, signal detection in noise, binaural beats, and sound localization using interaural time differences. These perceptual consequences are the opposite of what is typically observed in cochlear-impaired subjects who have impaired intensity perception but relatively normal temporal processing after taking their impaired intensity perception into account. These differences in perceptual consequences between auditory neuropathy and cochlear damage suggest the use of different neural codes in auditory perception: a suboptimal spike count code for intensity processing, a synchronized spike code for temporal processing, and a duplex code for frequency processing. We also proposed two underlying physiological models based on desynchronized and reduced discharge in the auditory nerve to successfully account for the observed neurological and behavioral data. These methods and measures cannot differentiate between these two AN models, but future studies using electric stimulation of the auditory nerve via a cochlear implant might. These results not only show the unique

Branchial cleft cyst encircling the hypoglossal nerve

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Long, Kristin L.; Spears, Carol; Kenady, Daniel E.

2013-01-01

Branchial cleft anomalies are a common cause of lateral neck masses and may present with infection, cyst enlargement or fistulas. They may affect any of the nearby neck structures, causing compressive symptoms or vessel thrombosis. We present a case of a branchial cleft cyst in a 10-year-old boy who had been present for 1year. At the time of operation, the cyst was found to completely envelop the hypoglossal nerve. While reports of hypoglossal nerve palsies due to external compression from cysts are known, we believe this to be the first report of direct nerve involvement by a branchial cleft cyst. PMID:24963902

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves.

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Barghash, Z; Larsen, J O; Al-Bishri, A; Kahnberg, K-E

2013-12-01

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function). Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Supraorbital keyhole surgery for optic nerve decompression and dura repair.

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Chen, Yuan-Hao; Lin, Shinn-Zong; Chiang, Yung-Hsiao; Ju, Da-Tong; Liu, Ming-Ying; Chen, Guann-Juh

2004-07-01

Supraorbital keyhole surgery is a limited surgical procedure with reduced traumatic manipulation of tissue and entailing little time in the opening and closing of wounds. We utilized the approach to treat head injury patients complicated with optic nerve compression and cerebrospinal fluid leakage (CSF). Eleven cases of basal skull fracture complicated with either optic nerve compression and/or CSF leakage were surgically treated at our department from February 1995 to June 1999. Six cases had primary optic nerve compression, four had CSF leakage and one case involved both injuries. Supraorbital craniotomy was carried out using a keyhole-sized burr hole plus a small craniotomy. The size of craniotomy approximated 2 x 3 cm2. The optic nerve was decompressed via removal of the optic canal roof and anterior clinoid process with high-speed drills. The defect of dura was repaired with two pieces of tensa fascia lata that were attached on both sides of the torn dural defect with tissue glue. Seven cases with optic nerve injury included five cases of total blindness and two cases of light perception before operation. Vision improved in four cases. The CSF leakage was stopped successfully in all four cases without complication. As optic nerve compression and CSF leakage are skull base lesions, the supraorbital keyhole surgery constitutes a suitable approach. The supraorbital keyhole surgery allows for an anterior approach to the skull base. This approach also allows the treatment of both CSF leakage and optic nerve compression. Our results indicate that supraorbital keyhole operation is a safe and effective method for preserving or improving vision and attenuating CSF leakage following injury.

MR of acoustic neuromas; Relationship to cranial nerves

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Suzuki, Masayuki; Takashima, Tsutomu; Kadoya, Masumi; Takahashi, Shiroh; Miyayama, Shiroh; Taira, Sakae; Kashihara, Kengo; Yamashima, Tetsumori; Itoh, Haruhide [Kanazawa Univ. (Japan). School of Medicine

1989-08-01

In this report, the relationship of acoustic neuromas to the adjacent cranial nerves is discussed. On T{sub 1}-weighted images, the trigeminal nerve was detected in all 13 cases. Mild to marked compression of these nerves by the tumors was observed in eight cases. The extent of compression did not always correspond to the clinical symptoms. In four cases with a maximum tumor diameter of 2 cm or less, the 7th and 8th cranial nerves were identified. There was no facial palsy in these patients. Two patients with a tumor diameter of more than 2 cm also had no facial palsy. All patients, including those with small tumors, complained of hearing loss and/or tinnitus. While MR imaging has some limitations, it is an effective imaging modality for showing the relationship between tumors and nerves. (author).

Diagnostic imaging of compression neuropathy

International Nuclear Information System (INIS)

Weishaupt, D.; Andreisek, G.

2007-01-01

Compression-induced neuropathy of peripheral nerves can cause severe pain of the foot and ankle. Early diagnosis is important to institute prompt treatment and to minimize potential injury. Although clinical examination combined with electrophysiological studies remain the cornerstone of the diagnostic work-up, in certain cases, imaging may provide key information with regard to the exact anatomic location of the lesion or aid in narrowing the differential diagnosis. In other patients with peripheral neuropathies of the foot and ankle, imaging may establish the etiology of the condition and provide information crucial for management and/or surgical planning. MR imaging and ultrasound provide direct visualization of the nerve and surrounding abnormalities. Bony abnormalities contributing to nerve compression are best assessed by radiographs and CT. Knowledge of the anatomy, the etiology, typical clinical findings, and imaging features of peripheral neuropathies affecting the peripheral nerves of the foot and ankle will allow for a more confident diagnosis. (orig.) [de

The effect of methylprednisolone on facial nerve paralysis with different etiologies.

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Yildirim, Mehmet Akif; Karlidag, Turgut; Akpolat, Nusret; Kaygusuz, Irfan; Keles, Erol; Yalcin, Sinasi; Akyigit, Abdulvahap

2015-05-01

The objective of this study was to evaluate the effectiveness of methylprednisolone (MP) in models of facial nerve paralysis obtained by nerve section, compression, or inoculation with herpes simplex virus (HSV). Experimental controlled animal study. Tertiary referral center. A total of 30 female New Zealand rabbits weighing 1200-3000 g were used for the study. They were randomly assigned to one of 6 groups of 5 animals each. A nerve section injury was realized in Groups 1a (section and MP) and 1b (section, control) rabbits. A compression-type injury was inflicted to rabbits in Groups 2a (compression and MP) and 2b (compression, control). As for animals in Groups 3a (Type 1 HSV and MP) and 3b (Type 1 HSV, controls), facial nerve paralysis resulting from viral infection was obtained. Animals in the 3 treatment groups, designated with the letter "a", were administered MP, 1 mg/kg/d, whereas those in control groups "b" received 1 mL normal saline, both during 3 weeks. All subjects were followed up for 2 months. At the end of this period, all animals had the buccal branch of the facial nerve excised on the operated side. Semi-thin sections of these specimens were evaluated under light microscopy for the following: perineural fibrosis, increase in collagen fibers, myelin degeneration, axonal degeneration, Schwann cell proliferation, and edema. No significant difference was observed (P > 0.05) between the MP treatment group and the control group with regard to perineural fibrosis, increase in collagen fibers, myelin degeneration, axonal degeneration, edema, or Schwann cell proliferation. In the group with a compressive lesion (Group 2), controls were no different from MP-treated animals as to perineural fibrosis, increase in collagen fibers, or Schwann cell proliferation, whereas axonal degeneration, myelin degeneration, and edema were significantly higher (P facial nerve palsy, we may say that this drug was without effect on nerve healing in paralysis due to nerve

Magnetic resonance imaging of vascular compression in trigeminal neuralgia and hemifacial spasms

International Nuclear Information System (INIS)

Nagaseki, Yoshishige; Horikoshi, Tohru; Omata, Tomohiro; Sugita, Masao; Nukui, Hideaki; Sakamoto, Hajime; Kumagai, Hiroshi; Sasaki, Hideo; Tsuji, Reizou.

1991-01-01

We show how neurosurgical planning can benefit from the better visualization of the precise vascular compression of the nerve provided by the oblique-sagittal and gradient-echo method (OS-GR image) using magnetic resonance images (MRI). The scans of 3 patients with trigeminal neuralgia (TN) and of 15 with hemifacial spasm (HFS) were analyzed for the presence and appearance of the vascular compression of the nerves. Imaging sequences consisted of an OS-GR image (TR/TE: 200/20, 3-mm-thick slice) cut along each nerve shown by the axial view, which was scanned at the angle of 105 degrees taken between the dorsal line of the brain stem and the line corresponding to the pontomedullary junction. In the OS-GR images of the TN's, the vascular compressions of the root entry zone (REZ) of the trigeminal nerve were well visualized as high-intensity lines in the 2 cases whose vessels were confirmed intraoperatively. In the other case, with atypical facial pain, vascular compression was confirmed at the rostral distal site on the fifth nerve, apart from the REZ. In the 15 cases of HFS, twelve OS-GR images (80%) demonstrated vascular compressions at the REZ of the facial nerves from the direction of the caudoventral side. During the surgery for these 12 cases, in 11 cases (excepting the 1 case whose facial nerve was not compressed by any vessels), vascular compressions were confirmed corresponding to the findings of the OS-GR images. Among the 10 OS-GR images on the non-affected side, two false-positive findings were visualized. It is concluded that OS-GR images obtained by means of MRI may serve as a useful planning aid prior to microvascular decompression for cases of TN and HFS. (author)

3D-MR myelography (3D-MRM) for the diagnosis of lumbal nerve root compression syndrome. A comparison with conventional myelography

International Nuclear Information System (INIS)

Eberhardt, K.E.W.; Hollenbach, H.P.; Huk, W.J.

1994-01-01

65 patients with nerve root compression syndrome were examined using a new type of MR-technique, which is comparable to the conventional X-ray myelography. The results of the prospective case study were compared with previous clinical experiences (1). For the examinations a 1.0 T whole body MR-system (Siemens Magnetom Impact) was used. A strong T 2 *-weighted 3D-FISP sequence (TR=73 ms, TE=21 ms, α=7 ) was applied in sagittal orientation using a circularly polarized oval spine coil. To obtain fat suppression a frequency selective 1-3-3-1 prepulse was applied prior to the imaging sequence. The acquired 3D-data set was evaluated using a Maximum Intensity Projection (MIP) program. Our results confirmed earlier experiences which showed that the diagnostic sensitivity of 3D-MR myelography (3D-MRM) is comparable to that of conventional X-ray myelography. In cases of severe spinal canal stenosis and spondylolisthesis, and in cases of postoperative scar tissue with nerve root compressions, the sensitivity of the 3D-MRM is higher as compared to that of conventional X-ray myelography. (orig.) [de

Complete Spinal Accessory Nerve Palsy From Carrying Climbing Gear.

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Coulter, Jess M; Warme, Winston J

2015-09-01

We report an unusual case of spinal accessory nerve palsy sustained while transporting climbing gear. Spinal accessory nerve injury is commonly a result of iatrogenic surgical trauma during lymph node excision. This particular nerve is less frequently injured by blunt trauma. The case reported here results from compression of the spinal accessory nerve for a sustained period-that is, carrying a load over the shoulder using a single nylon rope for 2.5 hours. This highlights the importance of using proper load-carrying equipment to distribute weight over a greater surface area to avoid nerve compression in the posterior triangle of the neck. The signs and symptoms of spinal accessory nerve palsy and its etiology are discussed. This report is particularly relevant to individuals involved in mountaineering and rock climbing but can be extended to anyone carrying a load with a strap over one shoulder and across the body. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Relationship between the internal laryngeal nerve and the triticeal cartilage: a potentially unrecognized compression site during anterior cervical spine and carotid endarterectomy operations.

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Tubbs, R Shane; Dixon, Joshua F; Loukas, Marios; Shoja, Mohammadali M; Cohen-Gadol, Aaron A

2010-06-01

The triticeal cartilage has received scant attention in the literature. To date, its relationship to the nearby internal laryngeal nerve has not been studied. Therefore, to elucidate further this anatomic relationship and its potential surgical implications, this study was performed. Eighty-six adult cadaveric sides underwent dissection of the internal laryngeal nerve near its penetration of the thyrohyoid membrane. The relationship of this nerve to the triticeal cartilage was documented. Measurements and histological analysis were performed on all cartilage specimens. We identified triticeal cartilage in 51% of the specimens and found it to be hyaline in nature. The triticeal cartilage was located in the upper, middle, and lower thirds of the thyrohyoid membrane in 14%, 66%, and 20% of sides, respectively. Regardless of the position of the triticeal cartilage within the thyrohyoid membrane, the internal laryngeal nerve crossed directly over the triticeal cartilage on 59% of sides. When present, the internal laryngeal nerve will cross over the triticeal cartilage in the majority of individuals. This relationship should be borne in mind during surgical manipulation in this area and when placing retractors during anterior neck operations including cervical discectomy/fusion and carotid endarterectomy. Compression of the internal laryngeal nerve against the solid triticeal cartilage can cause laryngeal nerve palsy and increase the risk of resultant postoperative aspiration.

Evaluation of trigeminal neurovascular compression in patients with trigeminal neuralgia with 3.0 T MRI

International Nuclear Information System (INIS)

Zhang Lirong; Wang Dehang; Wang Dongqing; Wu Min; Xu Guangming; Ma Cong

2012-01-01

Objective: To identify anatomical characteristics of neurovascular compression associated with trigeminal neuralgia (TN). Methods: Fifty patients with TN (23 of 50 patients underwent microvascular decompression) and 50 patients without facial pain underwent 3.0 T MRI scanning for analysis of 50 trigeminal nerves ipsilateral to TN symptoms, 50 contralateral to TN symptoms, and 100 in asymptomatic patients. MRI sequences included balanced fast-field echo and 3D MR angiography. Images were fused and reconstructed into virtual cisternoscopy images to determine the degree (severity of compression was defined as follows: 1=no compression; 2 =compressed by a vein; 3 =contacted by an artery; 4 =indented by an artery; and 5 =nerve displaced or distorted by an artery) and site of neurovascular compression (the point of each offending vascular structure: proximal was defined as located in 1/3 length of the cisternal segment of the trigeminal nerve near root entry zone; the place of superior was defined as above the cisternal segment of the trigeminal nerve). Reconstructed MPR images were used to measure nerve length and cross sectional area. The chi-square test was used for all 2 × 2 contingency tables. The t-test was used for dependent samples. The Logistic regression was used for prediction of occurrence of the event of TN. Results: Twenty-three of 50 patients with TN underwent microvascular decompression, which confirmed predicted neurovascular relationships in all cases, and 21 of 23 patients were pain free after the operation. The incidence of neurovascular compression on asymptomatic nerves (no. of level 1=79, level 2=5, level 3 =8, level 4 =8), on nerves contralateral to TN symptoms (no. of level 1=27, level 2 =6, level 3 =9, level 4 =8), and on nerves ipsilateral to TN symptoms (no. of level 1=4, level 2 =12, level 3 =12, level 4 =7, level 5 =15) was 21.0% (21/100), 46.0% (23/50), and 92.0% (46/50), respectively. The difference between symptomatic and asymptomatic

Salvage of cervical motor radiculopathy using peripheral nerve transfer reconstruction.

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Afshari, Fardad T; Hossain, Taushaba; Miller, Caroline; Power, Dominic M

2018-05-10

Motor nerve transfer surgery involves re-innervation of important distal muscles using either an expendable motor branch or a fascicle from an adjacent functioning nerve. This technique is established as part of the reconstructive algorithm for traumatic brachial plexus injuries. The reproducible outcomes of motor nerve transfer surgery have resulted in exploration of the application of this technique to other paralysing conditions. The objective of this study is to report feasibility and increase awareness about nerve transfer as a method of improving upper limb function in patients with cervical motor radiculopathy of different aetiology. In this case series we report 3 cases with different modes of injury to the spinal nerve roots with significant and residual motor radiculopathy that have been successfully treated with nerve transfer surgery with good functional outcomes. The cases involved iatrogenic nerve root injury, tumour related root compression and degenerative root compression. Nerve transfer surgery may offer reliable reconstruction for paralysis when there has been no recovery following a period of conservative management. However the optimum timing of nerve transfer intervention is not yet identified for patients with motor radiculopathy.

M. leprae components induce nerve damage by complement activation: identification of lipoarabinomannan as the dominant complement activator.

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Bahia El Idrissi, Nawal; Das, Pranab K; Fluiter, Kees; Rosa, Patricia S; Vreijling, Jeroen; Troost, Dirk; Morgan, B Paul; Baas, Frank; Ramaglia, Valeria

2015-05-01

Peripheral nerve damage is the hallmark of leprosy pathology but its etiology is unclear. We previously identified the membrane attack complex (MAC) of the complement system as a key determinant of post-traumatic nerve damage and demonstrated that its inhibition is neuroprotective. Here, we determined the contribution of the MAC to nerve damage caused by Mycobacterium leprae and its components in mouse. Furthermore, we studied the association between MAC and the key M. leprae component lipoarabinomannan (LAM) in nerve biopsies of leprosy patients. Intraneural injections of M. leprae sonicate induced MAC deposition and pathological changes in the mouse nerve, whereas MAC inhibition preserved myelin and axons. Complement activation occurred mainly via the lectin pathway and the principal activator was LAM. In leprosy nerves, the extent of LAM and MAC immunoreactivity was robust and significantly higher in multibacillary compared to paucibacillary donors (p = 0.01 and p = 0.001, respectively), with a highly significant association between LAM and MAC in the diseased samples (r = 0.9601, p = 0.0001). Further, MAC co-localized with LAM on axons, pointing to a role for this M. leprae antigen in complement activation and nerve damage in leprosy. Our findings demonstrate that MAC contributes to nerve damage in a model of M. leprae-induced nerve injury and its inhibition is neuroprotective. In addition, our data identified LAM as the key pathogen associated molecule that activates complement and causes nerve damage. Taken together our data imply an important role of complement in nerve damage in leprosy and may inform the development of novel therapeutics for patients.

Herniated gyrus rectus causing idiopathic compression of the optic chiasm.

Science.gov (United States)

Smith, Jacob; Jack, Megan M; Peterson, Jeremy C; Chamoun, Roukoz B

2017-02-01

Anomalies in the frontal lobe can interfere with visual function by compression of the optic chiasm and nerve. The gyrus rectus is located at the anterior cranial fossa floor superior to the intracranial optic nerves and chiasm. Compression of these structures by the gyrus rectus is often caused by neoplastic or dysplastic growth in the area. We report a rare case of a herniated gyrus rectus impinged on the optic chiasm and nerve without a clear pathological cause for the herniation. Copyright © 2016 Elsevier B.V. All rights reserved.

Changes in lumbosacral spinal nerve roots on diffusion tensor imaging in spinal stenosis

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Zhong-jun Hou

2015-01-01

Full Text Available Lumbosacral degenerative disc disease is a common cause of lower back and leg pain. Conventional T1-weighted imaging (T1WI and T2-weighted imaging (T2WI scans are commonly used to image spinal cord degeneration. However, these modalities are unable to image the entire lumbosacral spinal nerve roots. Thus, in the present study, we assessed the potential of diffusion tensor imaging (DTI for quantitative assessment of compressed lumbosacral spinal nerve roots. Subjects were 20 young healthy volunteers and 31 patients with lumbosacral stenosis. T2WI showed that the residual dural sac area was less than two-thirds that of the corresponding normal area in patients from L 3 to S 1 stenosis. On T1WI and T2WI, 74 lumbosacral spinal nerve roots from 31 patients showed compression changes. DTI showed thinning and distortion in 36 lumbosacral spinal nerve roots (49% and abruption in 17 lumbosacral spinal nerve roots (23%. Moreover, fractional anisotropy values were reduced in the lumbosacral spinal nerve roots of patients with lumbosacral stenosis. These findings suggest that DTI can objectively and quantitatively evaluate the severity of lumbosacral spinal nerve root compression.

Changes in lumbosacral spinal nerve roots on diffusion tensor imaging in spinal stenosis.

Science.gov (United States)

Hou, Zhong-Jun; Huang, Yong; Fan, Zi-Wen; Li, Xin-Chun; Cao, Bing-Yi

2015-11-01

Lumbosacral degenerative disc disease is a common cause of lower back and leg pain. Conventional T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) scans are commonly used to image spinal cord degeneration. However, these modalities are unable to image the entire lumbosacral spinal nerve roots. Thus, in the present study, we assessed the potential of diffusion tensor imaging (DTI) for quantitative assessment of compressed lumbosacral spinal nerve roots. Subjects were 20 young healthy volunteers and 31 patients with lumbosacral stenosis. T2WI showed that the residual dural sac area was less than two-thirds that of the corresponding normal area in patients from L3 to S1 stenosis. On T1WI and T2WI, 74 lumbosacral spinal nerve roots from 31 patients showed compression changes. DTI showed thinning and distortion in 36 lumbosacral spinal nerve roots (49%) and abruption in 17 lumbosacral spinal nerve roots (23%). Moreover, fractional anisotropy values were reduced in the lumbosacral spinal nerve roots of patients with lumbosacral stenosis. These findings suggest that DTI can objectively and quantitatively evaluate the severity of lumbosacral spinal nerve root compression.

Endoscopic treatment of sciatic nerve entrapment in deep gluteal syndrome: Clinical results.

Science.gov (United States)

Aguilera-Bohorquez, B; Cardozo, O; Brugiatti, M; Cantor, E; Valdivia, N

2018-05-25

Deep gluteal syndrome (DGS) is characterized by compression, at extra-pelvic level, of the sciatic nerve within any structure of the deep gluteal space. The objective was to evaluate the clinical results in patients with DGS treated with endoscopic technique. Retrospective study of patients with DGS treated with an endoscopic technique between 2012 and 2016 with a minimum follow-up of 12 months. The patients were evaluated before the procedure and during the first year of follow-up with the WOMAC and VAIL scale. Forty-four operations on 41 patients (36 women and 5 men) were included with an average age of 48.4±14.5. The most common cause of nerve compression was fibrovascular bands. There were two cases of anatomic variant at the exit of the nerve; compression of the sciatic nerve was associated with the use of biopolymers in the gluteal region in an isolated case. The results showed an improvement of functionality and pain measured with the WOMAC scale with a mean of 63 to 26 points after the procedure (Pnerve. Four cases required revision at 6 months following the procedure due to compression of the scarred tissue surrounding the sciatic nerve. Endoscopic release of the sciatic nerve offers an alternative in the management of DGS by improving functionality and reducing pain levels in appropriately selected patients. Copyright © 2018 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma.

Science.gov (United States)

Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M; Ginsberg, Lawrence E; Gidley, Paul W

2014-08-01

Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy.

Activated carbon from thermo-compressed wood and other lignocellulosic precursors

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Capart, R.

2007-05-01

Full Text Available The effects of thermo-compression on the physical properties such as bulk density, mass yield, surface area, and also adsorption capacity of activated carbon were studied. The activated carbon samples were prepared from thermo-compressed and virgin fir-wood by two methods, a physical activation with CO2 and a chemical activation with KOH. A preliminary thermo-compression method seems an easy way to confer to a tender wood a bulk density almost three times larger than its initial density. Thermo-compression increased yield regardless of the mode of activation. The physical activation caused structural alteration, which enhanced the enlargement of micropores and even their degradation, leading to the formation of mesopores. Chemical activation conferred to activated carbon a heterogeneous and exclusively microporous nature. Moreover, when coupled to chemical activation, thermo-compression resulted in a satisfactory yield (23%, a high surface area (>1700 m2.g-1, and a good adsorption capacity for two model pollutants in aqueous solution: methylene blue and phenol. Activated carbon prepared from thermo-compressed wood exhibited a higher adsorption capacity for both the pollutants than did a commercial activated carbon.

Theobromine inhibits sensory nerve activation and cough.

Science.gov (United States)

Usmani, Omar S; Belvisi, Maria G; Patel, Hema J; Crispino, Natascia; Birrell, Mark A; Korbonits, Márta; Korbonits, Dezso; Barnes, Peter J

2005-02-01

Cough is a common and protective reflex, but persistent coughing is debilitating and impairs quality of life. Antitussive treatment using opioids is limited by unacceptable side effects, and there is a great need for more effective remedies. The present study demonstrates that theobromine, a methylxanthine derivative present in cocoa, effectively inhibits citric acid-induced cough in guinea-pigs in vivo. Furthermore, in a randomized, double-blind, placebo-controlled study in man, theobromine suppresses capsaicin-induced cough with no adverse effects. We also demonstrate that theobromine directly inhibits capsaicin-induced sensory nerve depolarization of guinea-pig and human vagus nerve suggestive of an inhibitory effect on afferent nerve activation. These data indicate the actions of theobromine appear to be peripherally mediated. We conclude theobromine is a novel and promising treatment, which may form the basis for a new class of antitussive drugs.

The role of diagnostic radiology in compressive and entrapment neuropathies

International Nuclear Information System (INIS)

Spratt, J.D.; Stanley, A.J.; Hide, I.G.; Campbell, R.S.D.; Grainger, A.J.

2002-01-01

Diagnostic imaging is increasingly being utilised to aid the diagnosis of compression and entrapment neuropathies. Cross-sectional imaging, primarily ultrasound and magnetic resonance imaging, can provide exquisite anatomical detail of peripheral nerves and the changes that may occur as a result of compression. Imaging can provide a useful diagnostic aid to clinicians, which may supplement clinical evaluation, and may eventually provide an alternative to other diagnostic techniques such as nerve conduction studies. This article describes the abnormalities that may be demonstrated by current imaging techniques, and critically analyses the impact of imaging in diagnosis of peripheral compressive neuropathy. (orig.)

The role of diagnostic radiology in compressive and entrapment neuropathies

Energy Technology Data Exchange (ETDEWEB)

Spratt, J.D.; Stanley, A.J.; Hide, I.G.; Campbell, R.S.D. [Department of Radiology, James Cook University Hospital, Middlesbrough, TS4 3BW (United Kingdom); Grainger, A.J. [Department of Radiology, Leeds General Infirmary, Leeds (United Kingdom)

2002-09-01

Diagnostic imaging is increasingly being utilised to aid the diagnosis of compression and entrapment neuropathies. Cross-sectional imaging, primarily ultrasound and magnetic resonance imaging, can provide exquisite anatomical detail of peripheral nerves and the changes that may occur as a result of compression. Imaging can provide a useful diagnostic aid to clinicians, which may supplement clinical evaluation, and may eventually provide an alternative to other diagnostic techniques such as nerve conduction studies. This article describes the abnormalities that may be demonstrated by current imaging techniques, and critically analyses the impact of imaging in diagnosis of peripheral compressive neuropathy. (orig.)

A case of mental nerve paresthesia due to dynamic compression of alveolar inferior nerve along an elongated styloid process.

Science.gov (United States)

Gooris, Peter J J; Zijlmans, Jan C M; Bergsma, J Eelco; Mensink, Gertjan

2014-07-01

Spontaneous paresthesia of the mental nerve is considered an ominous clinical sign. Mental nerve paresthesia has also been referred to as numb chin syndrome. Several potentially different factors have been investigated for their role in interfering with the inferior alveolar nerve (IAN) and causing mental nerve neuropathy. In the present case, the patient had an elongated calcified styloid process that we hypothesized had caused IAN irritation during mandibular movement. This eventually resulted in progressive loss of sensation in the mental nerve region. To our knowledge, this dynamic irritation, with complete recovery after resection of the styloid process, has not been previously reported. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

A case of mental nerve paresthesia due to dynamic compression of alveolar inferior nerve along an elongated styloid process

NARCIS (Netherlands)

Gooris, P.J.J.; Zijlmans, J.C.M.; Bergsma, J.E.; Mensink, G.

2014-01-01

Spontaneous paresthesia of the mental nerve is considered an ominous clinical sign. Mental nerve paresthesia has also been referred to as numb chin syndrome. Several potentially different factors have been investigated for their role in interfering with the inferior alveolar nerve (IAN) and causing

RESISTIN, AN ADIPOKINE WITH NON-GENERALISED ACTIONS ON SYMPATHETIC NERVE ACTIVITY

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Emilio eBadoer

2015-11-01

Full Text Available The World Health Organisation has called obesity a global epidemic. There is a strong association between body weight gain and blood pressure. A major determinant of blood pressure is the level of activity in sympathetic nerves innervating cardiovascular organs. A characteristic of obesity, in both humans and in animal models, is an increase in sympathetic nerve activity to the skeletal muscle vasculature and to the kidneys. Obesity is now recognised as a chronic, low level inflammatory condition and pro-inflammatory cytokines are elevated including those produced by adipose tissue. The most well known adipokine released from fat tissue is leptin. The adipokine, resistin,, is also released from adipose tissue. Resistin can act in the central nervous system to influence the sympathetic nerve activity. Here, we review the effects of resistin on sympathetic nerve activity and compare them with leptin. We build an argument that resistin and leptin may have complex interactions. Firstly, they may augment each other as both are excitatory on sympathetic nerves innervating cardiovascular organs; In contrast, they could antagonize each other’s actions on brown adipose tissue, a key metabolic organ. These interactions may be important in conditions in which leptin and resistin are elevated, such as in obesity.

Resveratrol Promotes Nerve Regeneration via Activation of p300 Acetyltransferase-Mediated VEGF Signaling in a Rat Model of Sciatic Nerve Crush Injury.

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Ding, Zhuofeng; Cao, Jiawei; Shen, Yu; Zou, Yu; Yang, Xin; Zhou, Wen; Guo, Qulian; Huang, Changsheng

2018-01-01

Peripheral nerve injuries are generally associated with incomplete restoration of motor function. The slow rate of nerve regeneration after injury may account for this. Although many benefits of resveratrol have been shown in the nervous system, it is not clear whether resveratrol could promote fast nerve regeneration and motor repair after peripheral nerve injury. This study showed that the motor deficits caused by sciatic nerve crush injury were alleviated by daily systematic resveratrol treatment within 10 days. Resveratrol increased the number of axons in the distal part of the injured nerve, indicating enhanced nerve regeneration. In the affected ventral spinal cord, resveratrol enhanced the expression of several vascular endothelial growth factor family proteins (VEGFs) and increased the phosphorylation of p300 through Akt signaling, indicating activation of p300 acetyltransferase. Inactivation of p300 acetyltransferase reversed the resveratrol-induced expression of VEGFs and motor repair in rats that had undergone sciatic nerve crush injury. The above results indicated that daily systematic resveratrol treatment promoted nerve regeneration and led to rapid motor repair. Resveratrol activated p300 acetyltransferase-mediated VEGF signaling in the affected ventral spinal cord, which may have thus contributed to the acceleration of nerve regeneration and motor repair.

Peripheral nerve injury induces glial activation in primary motor cortex

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Julieta Troncoso

2015-02-01

Full Text Available Preliminary evidence suggests that peripheral facial nerve injuries are associated with sensorimotor cortex reorganization. We have characterized facial nerve lesion-induced structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with glial cell density using a rodent facial paralysis model. First, we used adult transgenic mice expressing green fluorescent protein in microglia and yellow fluorescent protein in pyramidal neurons which were subjected to either unilateral lesion of the facial nerve or sham surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1. It was found that facial nerve lesion induced long-lasting changes in dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Pyramidal cells’ dendritic arborization underwent overall shrinkage and transient spine pruning. Moreover, microglial cell density surrounding vM1 layer 5 pyramidal neurons was significantly increased with morphological bias towards the activated phenotype. Additionally, we induced facial nerve lesion in Wistar rats to evaluate the degree and extension of facial nerve lesion-induced reorganization processes in central nervous system using neuronal and glial markers. Immunoreactivity to NeuN (neuronal nuclei antigen, GAP-43 (growth-associated protein 43, GFAP (glial fibrillary acidic protein, and Iba 1 (Ionized calcium binding adaptor molecule 1 were evaluated 1, 3, 7, 14, 28 and 35 days after either unilateral facial nerve lesion or sham surgery. Patches of decreased NeuN immunoreactivity were found bilaterally in vM1 as well as in primary somatosensory cortex (CxS1. Significantly increased GAP-43 immunoreactivity was found bilaterally after the lesion in hippocampus, striatum, and sensorimotor cortex. One day after lesion GFAP immunoreactivity increased bilaterally in hippocampus, subcortical white

Neurovascular compression of cranial nerves: CT and MRI findings; Evaluacion de las compresiones neurovasculares intracraneales: hallazgos en TC y RM

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Almeida Llanos, Julio; Sinner, Ricardo; Nagel, Jorge [Instituto Gamma, Rosario (Argentina)

2002-07-01

Purpose: The compression of a nervous structure by an aberrant vessel may be asymptomatic or produce an important symptoms, in these cases CT and MRI show relevant information. Materials and Methods: Between January 1998 and March 2001, we studied 27 patients: 8 with trigeminal neuralgia, 7 with hemi facial spasm, 4 vertigo and tinnitus, 2 hemianopsia, 1 with neuralgia of the amygdalin fossa, 1 with bitonal voice, 1 with tongue deviation with fascicular movements, 2 essential hypertension and 1 with severe headache. All of them had a neurologic evaluation from 2 specialists and 2 neuro radiologists interpreted the results. Results: The CT and RMI images with special sequences allowed to prove the compression of the entry segments of the V, VII, IX, X and XII cranial nerves, of the optic chiasma and the ventrolateral aspect of the medulla oblongata in close relation with the vasopressor centre. Also they demonstrate a rare vessel in the Silvio aqueduct avoiding the normal flow of the CSF. Of the total of patients that were studied, 37% had surgical confirmation. Conclusion: CT and RMI are sensitive and specific methods for the detection of vascular compressions of nervous structures. (author)

Comparative study of 3D TOF-SPGR and 3D FASE on the display of the relationship between cranial nerves and peripheral vessels

International Nuclear Information System (INIS)

Sun Wenge; Li Yanliang; Zhang Lina; Qi Xixun; Jin Anyu; Xu Ke; Tong Zhiyong; Liu Jing

2004-01-01

Objective: To select a better sequence which can supply reliable radiological information for vessel compression on cranial nerves in patients with facial spasm or trigeminal neuralgia. Methods: 3D TOF-SPGR and 3D FASE were used in 40 patients with facial spasm or trigeminal neuralgia to display the relationship between cranial nerves (facial nerve and trigeminal nerve) and peripheral vessels. Results: 38 patients got surgical results. 33 unilateral vessel compression or contact on facial nerves or trigeminal nerves was found on 3D TOF-SPGR, while no contact was found in 5. 26 unilateral vessel compression or contact on facial nerves or trigeminal nerves was found on 3D FASE, while no contact was found in 12. Significant difference between the two sequences on the display of vessel compression on facial nerves or trigeminal nerves was found by statistical analysis (χ 2 =5.14, P=0.016). Conclusion: 3D TOF-SPGR is better than 3D FASE on display of the relationship between nerves and peripheral vessels, and it should be the primary MRI sequence for patients with facial spasm or trigeminal neuralgia clinically. (author)

Laser-activated solid protein bands for peripheral nerve repair: an vivo study.

Science.gov (United States)

Lauto, A; Trickett, R; Malik, R; Dawes, J M; Owen, E R

1997-01-01

Severed tibial nerves in rats were repaired using a novel technique, utilizing a semiconductor diode-laser-activated protein solder applied longitudinally across the join. Welding was produced by selective laser denaturation of solid solder bands containing the dye indocyanine green. An in vivo study, using 48 adult male Wistar rats, compared conventional microsuture-repaired tibial nerves with laser solder-repaired nerves. Nerve repairs were characterised immediately after surgery and after 3 months. Successful regeneration with average compound muscle action potentials of 2.5 +/- 0.5 mV and 2.7 +/- 0.3 mV (mean and standard deviation) was demonstrated for the laser-soldered nerves and the sutured nerves, respectively. Histopathology confirmed comparable regeneration of axons in laser- and suture-operated nerves. The laser-based nerve repair technique was easier and faster than microsuture repair, minimising manipulation damage to the nerve.

Active RF Pulse Compression Using An Electrically Controlled Semiconductor Switch

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Guo, Jiquan; Tantawi, Sami; /SLAC

2007-01-10

First we review the theory of active pulse compression systems using resonant delay lines. Then we describe the design of an electrically controlled semiconductor active switch. The switch comprises an active window and an overmoded waveguide three-port network. The active window is based on a four-inch silicon wafer which has 960 PIN diodes. These are spatially combined in an overmoded waveguide. We describe the philosophy and design methodology for the three-port network and the active window. We then present the results of using this device to compress 11.4 GHz RF signals with high compression ratios. We show how the system can be used with amplifier like sources, in which one can change the phase of the source by manipulating the input to the source. We also show how the active switch can be used to compress a pulse from an oscillator like sources, which is not possible with passive pulse compression systems.

An unusual case of suprascapular nerve neuropathy: a case report

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Kyriakides Theodoros

2011-08-01

Full Text Available Abstract Introduction Suprascapular nerve neuropathy constitutes an unusual cause of shoulder weakness, with the most common etiology being nerve compression from a ganglion cyst at the suprascapular or spinoglenoid notch. We present a puzzling case of a man with suprascapular nerve neuropathy that may have been associated with an appendectomy. The case was attributed to nerve injury as the most likely cause that may have occurred during improper post-operative patient mobilization. Case presentation A 23-year-old Caucasian man presented to an orthopedic surgeon with a history of left shoulder weakness of several weeks' duration. The patient complained of pain and inability to lift minimal weight, such as a glass of water, following an appendectomy. His orthopedic clinical examination revealed obvious atrophy of the supraspinatus and infraspinatus muscles and 2 of 5 muscle strength scores on flexion resistance and external rotation resistance. Magnetic resonance imaging showed diffuse high signal intensity within the supraspinatus and infraspinatus muscles and early signs of minimal fatty infiltration consistent with denervation changes. No compression of the suprascapular nerve in the suprascapular or spinoglenoid notch was noted. Electromyographic studies showed active denervation effects in the supraspinatus muscle and more prominent in the left infraspinatus muscle. The findings were compatible with damage to the suprascapular nerve, especially the part supplying the infraspinatus muscle. On the basis of the patient's history, clinical examination, and imaging studies, the diagnosis was suspected to be associated with a possible traction injury of the suprascapular nerve that could have occurred during the patient's transfer from the operating table following an appendectomy. Conclusion Our case report may provide important insight into patient transfer techniques used by hospital personnel, may elucidate the clinical significance of careful

Coordinated Respiratory Motor Activity in Nerves Innervating the Upper Airway Muscles in Rats.

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Satoshi Tachikawa

Full Text Available Maintaining the patency of the upper airway during breathing is of vital importance. The activity of various muscles is related to the patency of the upper airway. In the present study, we examined the respiratory motor activity in the efferent nerves innervating the upper airway muscles to determine the movements of the upper airway during respiration under normocapnic conditions (pH = 7.4 and in hypercapnic acidosis (pH = 7.2. Experiments were performed on arterially perfused decerebrate rats aged between postnatal days 21-35. We recorded the efferent nerve activity in a branch of the cervical spinal nerve innervating the infrahyoid muscles (CN, the hypoglossal nerve (HGN, the external branch of the superior laryngeal nerve (SLN, and the recurrent laryngeal nerve (RLN with the phrenic nerve (PN. Inspiratory nerve discharges were observed in all these nerves under normocapnic conditions. The onset of inspiratory discharges in the CN and HGN was slightly prior to those in the SLN and RLN. When the CO2 concentration in the perfusate was increased from 5% to 8% to prepare for hypercapnic acidosis, the peak amplitudes of the inspiratory discharges in all the recorded nerves were increased. Moreover, hypercapnic acidosis induced pre-inspiratory discharges in the CN, HGN, SLN, and RLN. The onset of pre-inspiratory discharges in the CN, HGN, and SLN was prior to that of discharges in the RLN. These results suggest that the securing of the airway that occurs a certain time before dilation of the glottis may facilitate ventilation and improve hypercapnic acidosis.

Acute radial nerve entrapment at the spiral groove: detection by DTI-based neurography

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Jengojan, Suren; Breitenseher, Julia; Weber, Michael; Prayer, Daniela; Kasprian, Gregor [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Neuro- and Musculosceletal Radiology, Vienna (Austria); Kovar, Florian [Medical University of Vienna, Department of Trauma-Surgery, Vienna (Austria)

2015-06-01

This study evaluated the potential of three-tesla diffusion tensor imaging (DTI) and tractography to detect changes of the radial (RN) and median (MN) nerves during transient upper arm compression by a silicon ring tourniquet. Axial T2-weighted and DTI sequences (b = 700 s/mm{sup 2}, 16 gradient encoding directions) of 13 healthy volunteers were obtained. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the MN and RN were measured at the spiral groove and further visualized in 3D by deterministic tractography (thresholds: FA =.15, angle change = 27 ). Local/lesional RN FA values increased (p = 0.001) and ADC values decreased (p = 0.02) during a 20-min upper arm compression, whereas no significant FA (p = 0.49) or ADC (p = 0.73) changes of the MN were detected. There were no T2-w nerve signal changes or alterations of nerve trajectories in 3D. Acute nerve compression of the RN leads to changes of its three-tesla DTI metrics. Peripheral nerve DTI provides non-invasive insights into the ''selective'' vulnerability of the RN at the spiral groove. (orig.)

Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

Energy Technology Data Exchange (ETDEWEB)

AlbarracIn, A L [Catedra de Neurociencias, Facultad de Medicina, Universidad Nacional de Tucuman, Av. Roca 2200, PC 4000 (Argentina); Farfan, F D [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina); Felice, C J [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina)

2007-11-15

In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle.

Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

International Nuclear Information System (INIS)

AlbarracIn, A L; Farfan, F D; Felice, C J

2007-01-01

In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle

Usefulness of muscle denervation as an MRI sign of peripheral nerve pathology

International Nuclear Information System (INIS)

Lisle, D. A.; Johnstone, S. A.

2007-01-01

Full text: Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non-compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T 2 relaxation time, producing increased signal in skeletal muscle on short tau inversion-recovery and fat-suppressed T 2 -weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T 1 -weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders

A case of fibrolipomatous hamartoma of the median nerve with macrodactyly

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Sathish Arakeri

2012-07-01

Full Text Available Fibrolipomatous hamartoma of nerve is a tumor-like lipomatous process principally involving affecting young persons. The median nerve is most commonly affectedinvolved. The lesion is characterized by a soft slowly growing mass, surrounding and infiltrating major nerves and their branches. It may cause symptoms of compression neuropathy and is associated with macrodactyly in one third of cases. Here, we present a case of Fibrolipomatous hamartoma of nerve in the wrist of a young man arising from median nerve. Debulking of the tumour was performed.

Patterns of motor activity in the isolated nerve cord of the octopus arm.

Science.gov (United States)

Gutfreund, Yoram; Matzner, Henry; Flash, Tamar; Hochner, Binyamin

2006-12-01

The extremely flexible octopus arm provides a unique opportunity for studying movement control in a highly redundant motor system. We describe a novel preparation that allows analysis of the peripheral nervous system of the octopus arm and its interaction with the muscular and mechanosensory elements of the arm's intrinsic muscular system. First we examined the synaptic responses in muscle fibers to identify the motor pathways from the axial nerve cord of the arm to the surrounding musculature. We show that the motor axons project to the muscles via nerve roots originating laterally from the arm nerve cord. The motor field of each nerve is limited to the region where the nerve enters the arm musculature. The same roots also carry afferent mechanosensory information from the intrinsic muscle to the axial nerve cord. Next, we characterized the pattern of activity generated in the dorsal roots by electrically stimulating the axial nerve cord. The evoked activity, although far reaching and long lasting, cannot alone account for the arm extension movements generated by similar electrical stimulation. The mismatch between patterns of activity in the isolated cord and in an intact arm may stem from the involvement of mechanosensory feedback in natural arm extension.

Arterial relationships to the nerves and some rigid structures in the posterior cranial fossa.

Science.gov (United States)

Surchev, N

2008-09-01

The close relationships between the cranial nerves and the arterial vessels in the posterior cranial fossa are one of the predisposing factors for artery-nerve compression. The aim of this study was to examine the relationships of the vertebral and basilar arteries to some skull and dural structures and the nerves in the posterior cranial fossa. For this purpose, the skull bases and brains of 70 cadavers were studied. The topographic relationships of the vertebral and basilar arteries to the cranial nerves in the posterior cranial fossa were studied and the distances between the arteries and some osseous formations were measured. The most significant variations in arterial position were registered in the lower half of the basilar artery. Direct contact with an artery was established for the hypoglossal canal, jugular tubercle, and jugular foramen. The results reveal additional information about the relationships of the nerves and arteries to the skull and dural formations in the posterior cranial fossa. New quantitative information is given to illustrate them. The conditions for possible artery-nerve compression due to arterial dislocation are discussed and two groups (lines) of compression points are suggested. The medial line comprises of the brain stem points, usually the nerve root entry/exit zone. The lateral line includes the skull eminences, on which the nerves lie, or skull and dural foramina through which they exit the cranial cavity. (c) 2008 Wiley-Liss, Inc.

Imaging of the optic nerve

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Becker, Minerva [Head and Neck and Maxillofacial Radiology, Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland)], E-mail: minerva.becker@hcuge.ch; Masterson, Karen [Head and Neck and Maxillofacial Radiology, Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland); Delavelle, Jacqueline [Neuroradiology, Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland); Viallon, Magalie [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland); Vargas, Maria-Isabel [Neuroradiology, Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland); Becker, Christoph D. [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, CH - 1211 Geneva 14 (Switzerland)

2010-05-15

This article provides an overview of the imaging findings of diseases affecting the optic nerve with special emphasis on clinical-radiological correlation and on the latest technical developments in MR imaging and CT. The review deals with congenital malformations, tumors, toxic/nutritional and degenerative entities, inflammatory and infectious diseases, compressive neuropathy, vascular conditions and trauma involving the optic nerve from its ocular segment to the chiasm. The implications of imaging findings on patient management and outcome and the importance of performing high-resolution tailored examinations adapted to the clinical situation are discussed.

Imaging of the optic nerve

International Nuclear Information System (INIS)

Becker, Minerva; Masterson, Karen; Delavelle, Jacqueline; Viallon, Magalie; Vargas, Maria-Isabel; Becker, Christoph D.

2010-01-01

This article provides an overview of the imaging findings of diseases affecting the optic nerve with special emphasis on clinical-radiological correlation and on the latest technical developments in MR imaging and CT. The review deals with congenital malformations, tumors, toxic/nutritional and degenerative entities, inflammatory and infectious diseases, compressive neuropathy, vascular conditions and trauma involving the optic nerve from its ocular segment to the chiasm. The implications of imaging findings on patient management and outcome and the importance of performing high-resolution tailored examinations adapted to the clinical situation are discussed.

Nerve transection repair using laser-activated chitosan in a rat model.

Science.gov (United States)

Bhatt, Neel K; Khan, Taleef R; Mejias, Christopher; Paniello, Randal C

2017-08-01

Cranial nerve transection during head and neck surgery is conventionally repaired with microsuture. Previous studies have demonstrated recovery with laser nerve welding (LNW), a novel alternative to microsuture. LNW has been reported to have poorer tensile strength, however. Laser-activated chitosan, an adhesive biopolymer, may promote nerve recovery while enhancing the tensile strength of the repair. Using a rat posterior tibial nerve injury model, we compared four different methods of nerve repair in this pilot study. Animal study. Animals underwent unilateral posterior tibial nerve transection. The injury was repaired by potassium titanyl phosphate (KTP) laser alone (n = 20), KTP + chitosan (n = 12), microsuture + chitosan (n = 12), and chitosan alone (n = 14). Weekly walking tracks were conducted to measure functional recovery (FR). Tensile strength (TS) was measured at 6 weeks. At 6 weeks, KTP laser alone had the best recovery (FR = 93.4% ± 8.3%). Microsuture + chitosan, KTP + chitosan, and chitosan alone all showed good FR (87.4% ± 13.5%, 84.6% ± 13.0%, and 84.1% ± 10.0%, respectively). One-way analysis of variance was performed (F(3,56) = 2.6, P = .061). A TS threshold of 3.8 N was selected as a control mean recovery. Three groups-KTP alone, KTP + chitosan, and microsuture + chitosan-were found to meet threshold 60% (95% confidence interval [CI]: 23.1%-88.3%), 75% (95% CI: 46.8%-91.1%), and 100% (95% CI: 75.8%-100.0%), respectively. In the posterior tibial nerve model, all repair methods promoted nerve recovery. Laser-activated chitosan as a biopolymer anchor provided good TS and appears to be a novel alternative to microsuture. This repair method may have surgical utility following cranial nerve injury during head and neck surgery. NA Laryngoscope, 127:E253-E257, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Activity-dependent intracellular Ca2+ transients in unmyelinated nerve fibres of the isolated adult rat vagus nerve.

Science.gov (United States)

Wächtler, J; Mayer, C; Grafe, P

1998-04-01

Confocal laser scanning microscopy was used to follow changes in the free intracellular calcium concentration ([Ca2+]i) in nerve fibres and adjacent Schwann cells in isolated rat vagus nerves. [Ca2+]i was monitored by the Ca2+-sensitive fluorescent dyes Calcium Green-1 and Fura Red. Intracellular Ca2+ transients were observed during repetitive (1-50 Hz) supramaximal electrical stimulation or by bath application of ATP. Trains of action potentials were more effective at elongated, fibre-like structures of the vagus nerves, whereas ATP-induced Ca2+ transients were found predominantly in regions of Schwann cell bodies. Activity-induced Ca2+ signals were unaffected by pharmacological manipulation of intracellular Ca2+ stores, during long-lasting application of purinergic receptor agonists, or by substitution of extracellular Na+ with Li+. However, they were abolished in the presence of Ca2+-free bathing solution or after the blocking of Ca2+ channels with Cd2+. Ca2+ transients were also observed during Ca2+ action potentials. Such "Ca2+ spikes" were elicited by electrical stimulation in the presence of a combination of tetrodotoxin and K+ channel blockers. These data suggest that voltage-dependent Ca2+ channels, activated during short trains of Na+ action potentials, produce an increase in intra-axonal [Ca2+] of rat vagus nerves. We did not find evidence for activity-dependent Ca2+ transients in the Schwann cells surrounding the unmyelinated axons.

Hericium erinaceus (Bull.: Fr.) Pers., a medicinal mushroom, activates peripheral nerve regeneration.

Science.gov (United States)

Wong, Kah-Hui; Kanagasabapathy, Gowri; Naidu, Murali; David, Pamela; Sabaratnam, Vikineswary

2016-10-01

To study the ability of aqueous extract of Hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats. Aqueous extract of Hericium erinaceus was given by daily oral administration following peroneal nerve crush injury in Sprague-Dawley rats. The expression of protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways; and c-Jun and c-Fos genes were studied in dorsal root ganglia (DRG) whereas the activity of protein synthesis was assessed in peroneal nerves by immunohistochemical method. Peripheral nerve injury leads to changes at the axonal site of injury and remotely located DRG containing cell bodies of sensory afferent neurons. Immunofluorescence studies showed that DRG neurons ipsilateral to the crush injury in rats of treated groups expressed higher immunoreactivities for Akt, MAPK, c-Jun and c-Fos as compared with negative control group (P <0.05). The intensity of nuclear ribonucleoprotein in the distal segments of crushed nerves of treated groups was significantly higher than in the negative control group (P <0.05). H. erinaceus is capable of promoting peripheral nerve regeneration after injury. Potential signaling pathways include Akt, MAPK, c-Jun, and c-Fos, and protein synthesis have been shown to be involved in its action.

Patterns of neurovascular compression in patients with classic trigeminal neuralgia: A high-resolution MRI-based study

International Nuclear Information System (INIS)

Lorenzoni, José; David, Philippe; Levivier, Marc

2012-01-01

Purpose: To describe the anatomical characteristics and patterns of neurovascular compression in patients suffering classic trigeminal neuralgia (CTN), using high-resolution magnetic resonance imaging (MRI). Materials and methods: The analysis of the anatomy of the trigeminal nerve, brain stem and the vascular structures related to this nerve was made in 100 consecutive patients treated with a Gamma Knife radiosurgery for CTN between December 1999 and September 2004. MRI studies (T1, T1 enhanced and T2-SPIR) with axial, coronal and sagital simultaneous visualization were dynamically assessed using the software GammaPlan™. Three-dimensional reconstructions were also developed in some representative cases. Results: In 93 patients (93%), there were one or several vascular structures in contact, either, with the trigeminal nerve, or close to its origin in the pons. The superior cerebellar artery was involved in 71 cases (76%). Other vessels identified were the antero-inferior cerebellar artery, the basilar artery, the vertebral artery, and some venous structures. Vascular compression was found anywhere along the trigeminal nerve. The mean distance between the nerve compression and the origin of the nerve in the brainstem was 3.76 ± 2.9 mm (range 0–9.8 mm). In 39 patients (42%), the vascular compression was located proximally and in 42 (45%) the compression was located distally. Nerve dislocation or distortion by the vessel was observed in 30 cases (32%). Conclusions: The findings of this study are similar to those reported in surgical and autopsy series. This non-invasive MRI-based approach could be useful for diagnostic and therapeutic decisions in CTN, and it could help to understand its pathogenesis.

Neuropatía compresiva del nervio interoseo posterior a nivel del codo (síndrome de la arcada de frohse: ¿debe incluirse en el listado de enfermedades profesionales? Must the neuropathy compressive of posterior interoseal nerve at the elbow level (arcade of frohse syndrome: be included in the occupational diseases list?

Directory of Open Access Journals (Sweden)

Raúl Jesús Regal Ramos

2010-09-01

Full Text Available Introducción: La afectación compresiva del nervio radial se encuentra recogida en el último Listado de Enfermedades Profesionales (LEP, con el código 2F0601. En este apartado no se recoge entre las "principales actividades" capaces de producir afectación del n.radial la compresión de origen laboral más frecuente de este, el síndrome de la Arcada de Frohse (SAF. Objetivos: El objetivo de esta revisión no es solo reflejar que la afectación compresiva del nervio interóseo posterior puede considerarse una Enfermedad Profesional (EP, sino que además debería estar recogida en el actual listado de EP entre las "principales actividades capaces de producir afectación del nervio radial". Metodología: Se han revisado hasta Febrero de 2010 las siguientes bases de datos bibliográficas: Medline, Embase, Cochrane. Resultados: Esta revisión bibliográfica nos permite concluir que: El SAF puede tener un origen laboral (la fibrosis del supinador corto se relaciona con movimientos repetidos de pronación y supinación del antebrazo y esta descrita su mayor prevalencia en determinadas profesiones que realizan estos movimientos. El SAF es la neuropatía compresiva de origen laboral mas frecuente del nervio radial, la más relacionada con los movimientos repetitivos de la mano y antebrazo. La Arcada de Frohse es el lugar más frecuente de compresión del radial. Conclusiones: Por tanto, el SAF puede considerarse una EP, si asocia factores de riesgo laborales suficientes, y debería estar recogido en el LEP por tratarse de la localización más frecuente de compresión de origen laboral del nervio radial.Introduction: The compress affection of radial nerve is included in the last Occupational Diseases List (ODL, with code 2f0601. In this paragraph the Arcade of Frohse syndrome (SAF isn't included among the "main activities" able to induce radial nerve affection, the occupational origin radial nerve compression more frequent. Objectives: The objective

Optimising the image of the intradural nerve root: the value of MR radiculography

Energy Technology Data Exchange (ETDEWEB)

Hofman, P.A.M. [Department of Diagnostic Radiology, University Hospital Maastricht (Netherlands); Wilmink, J.T. [Department of Diagnostic Radiology, University Hospital Maastricht (Netherlands)

1996-10-01

We evaluated the additional value of MR radiculography for increasing the sensitivity and specificity of MRI with regard to nerve root compression in patients with sciatica. The single slices of a heavily T 2-weighted oblique coronal image set were reformatted with a maximum intensity projection protocol. This image resembles a classical contrast radiculogram and shows the intradural nerve root and its sleeve. In 43 patients studied with a standard MRI examination there was a need for further assessment of nerve root compression in 19 (44 %). In 13 (68 %) of these, MR radiculography made a definite verdict possible. (orig.). With 4 figs., 2 tabs.

Optimising the image of the intradural nerve root: the value of MR radiculography

International Nuclear Information System (INIS)

Hofman, P.A.M.; Wilmink, J.T.

1996-01-01

We evaluated the additional value of MR radiculography for increasing the sensitivity and specificity of MRI with regard to nerve root compression in patients with sciatica. The single slices of a heavily T 2-weighted oblique coronal image set were reformatted with a maximum intensity projection protocol. This image resembles a classical contrast radiculogram and shows the intradural nerve root and its sleeve. In 43 patients studied with a standard MRI examination there was a need for further assessment of nerve root compression in 19 (44 %). In 13 (68 %) of these, MR radiculography made a definite verdict possible. (orig.). With 4 figs., 2 tabs

Sensorimotor peripheral nerve function and physical activity in older men

DEFF Research Database (Denmark)

Lange-Maia, B. S.; Cauley, J A; Newman, Anne B

2016-01-01

We determined whether sensorimotor peripheral nerve (PN) function was associated with physical activity (PA) in older men. The Osteoporotic Fractures in Men Study Pittsburgh, PA, site (n = 328, age 78.8 ± 4.7 years) conducted PN testing, including: peroneal motor and sural sensory nerve conduction...... (latencies, amplitudes: CMAP and SNAP for motor and sensory amplitude, respectively), 1.4g/10g monoflament (dorsum of the great toe), and neuropathy symptoms. ANOVA and multivariate linear regression modeled PN associations with PA (Physical Activity Scale for the Elderly [PASE] and SenseWear Armband). After...

Developmental Changes in the Connective Tissues of the Porcine Recurrent Laryngeal Nerve

OpenAIRE

Campbell, Ellen O.; Samlan, Robin A.; McMullen, Nathaniel T.; Cook, Sarah; Smiley-Jewell, Suzette; Barkmeier-Kraemer, Julie

2013-01-01

The recurrent laryngeal nerve (RLN) branches from the vagus cranial nerve to innervate structures important for voicing and swallowing. Damage to this nerve, commonly associated with surgery or idiopathic etiologies that largely occur with aging, results in impaired voicing and swallowing. Sunderland proposed a model of peripheral nerve damage whereby a nerve’s ability to resist damage from stretch and compression is determined by the quantity and composition of its epineurial connective tiss...

Development of Kinematic Graphs of Median Nerve during Active Finger Motion: Implications of Smartphone Use.

Directory of Open Access Journals (Sweden)

Hoi-Chi Woo

Full Text Available Certain hand activities cause deformation and displacement of the median nerve at the carpal tunnel due to the gliding motion of tendons surrounding it. As smartphone usage escalates, this raises the public's concern whether hand activities while using smartphones can lead to median nerve problems.The aims of this study were to 1 develop kinematic graphs and 2 investigate the associated deformation and rotational information of median nerve in the carpal tunnel during hand activities.Dominant wrists of 30 young adults were examined with ultrasonography by placing a transducer transversely on their wrist crease. Ultrasound video clips were recorded when the subject performing 1 thumb opposition with the wrist in neutral position, 2 thumb opposition with the wrist in ulnar deviation and 3 pinch grip with the wrist in neutral position. Six still images that were separated by 0.2-second intervals were then captured from the ultrasound video for the determination of 1 cross-sectional area (CSA, 2 flattening ratio (FR, 3 rotational displacement (RD and 4 translational displacement (TD of median nerve in the carpal tunnel, and these collected information of deformation, rotational and displacement of median nerve were compared between 1 two successive time points during a single hand activity and 2 different hand motions at the same time point. Finally, kinematic graphs were constructed to demonstrate the mobility of median nerve during different hand activities.Performing different hand activities during this study led to a gradual reduction in CSA of the median nerve, with thumb opposition together with the wrist in ulnar deviation causing the greatest extent of deformation of the median nerve. Thumb opposition with the wrist in ulnar deviation also led to the largest extent of TD when compared to the other two hand activities of this study. Kinematic graphs showed that the motion pathways of median nerve during different hand activities were complex

MR imaging findings of anterior interosseous nerve lesions

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Dunn, Andrew J. [Royal Liverpool University Hospital, Department of Medical Imaging, Liverpool (United Kingdom); Salonen, David C. [University of Toronto, Toronto Western Hospital, Department of Medical Imaging, Toronto, Ontario (Canada); Anastakis, Dimitri J. [University of Toronto, Toronto Western Hospital, Division of Plastic Surgery, Toronto, Ontario (Canada)

2007-12-15

To study and characterise the MR imaging findings of lesions of the anterior interosseous nerve (AIN). Magnetic resonance imaging (MRI) findings of the forearm of ten patients referred to our institution with suspected AIN lesions were retrospectively studied. Five healthy volunteers with normal forearm MRI findings formed a control group. Two musculoskeletal radiologists assessed the forearm musculature for oedema in the distribution of the AIN, median, posterior interosseous and radial nerves on T2-weighted (T2W) fat-saturated sequences. T1-weighted (T1W) images were assessed and graded for the presence of muscle atrophy and fatty involution. Six patients had undergone surgical exploration; five of these had surgically confirmed AIN compression. Four patients had diagnoses other than AIN compression made on imaging features. Of the cases of proven AIN compression, oedema within the pronator quadratus (PQ) muscle was identified in all cases. PQ atrophy and fatty involution were seen in three (43%) surgically confirmed cases. Cases 2 and 3 also demonstrated oedema in the flexor digitorum profundus (FDP)1 and FDP2 muscles. These cases also showed oedema in the flexor-carpi radialis (FCR) and FDP3/FDP4 muscles, respectively. The four cases of non-AIN compression demonstrated muscle oedema patterns that were atypical for the AIN distribution. They included a rupture of the flexor pollicis longus (FPL) tendon, brachial neuritis, amyotrophic lateral sclerosis and compression of the proximal median nerve. MRI is a useful investigation in the diagnostic workup of AIN syndrome. AIN syndrome is likely when there is diffuse oedema of AIN innervated muscles on T2W fat-saturated images. The most reliable sign of an AIN lesion is oedema within the PQ. Oedema in the flexor carpi radialis, FDP3 and FDP4, although not in the classical distribution of the AIN, does not preclude the diagnosis of AIN syndrome. (orig.)

MR imaging findings of anterior interosseous nerve lesions

International Nuclear Information System (INIS)

Dunn, Andrew J.; Salonen, David C.; Anastakis, Dimitri J.

2007-01-01

To study and characterise the MR imaging findings of lesions of the anterior interosseous nerve (AIN). Magnetic resonance imaging (MRI) findings of the forearm of ten patients referred to our institution with suspected AIN lesions were retrospectively studied. Five healthy volunteers with normal forearm MRI findings formed a control group. Two musculoskeletal radiologists assessed the forearm musculature for oedema in the distribution of the AIN, median, posterior interosseous and radial nerves on T2-weighted (T2W) fat-saturated sequences. T1-weighted (T1W) images were assessed and graded for the presence of muscle atrophy and fatty involution. Six patients had undergone surgical exploration; five of these had surgically confirmed AIN compression. Four patients had diagnoses other than AIN compression made on imaging features. Of the cases of proven AIN compression, oedema within the pronator quadratus (PQ) muscle was identified in all cases. PQ atrophy and fatty involution were seen in three (43%) surgically confirmed cases. Cases 2 and 3 also demonstrated oedema in the flexor digitorum profundus (FDP)1 and FDP2 muscles. These cases also showed oedema in the flexor-carpi radialis (FCR) and FDP3/FDP4 muscles, respectively. The four cases of non-AIN compression demonstrated muscle oedema patterns that were atypical for the AIN distribution. They included a rupture of the flexor pollicis longus (FPL) tendon, brachial neuritis, amyotrophic lateral sclerosis and compression of the proximal median nerve. MRI is a useful investigation in the diagnostic workup of AIN syndrome. AIN syndrome is likely when there is diffuse oedema of AIN innervated muscles on T2W fat-saturated images. The most reliable sign of an AIN lesion is oedema within the PQ. Oedema in the flexor carpi radialis, FDP3 and FDP4, although not in the classical distribution of the AIN, does not preclude the diagnosis of AIN syndrome. (orig.)

Bony exostosis of the atlas with resultant cranial nerve palsy

International Nuclear Information System (INIS)

Slavotinek, J.P.; Sage, M.R.; Brophy, B.P.

1991-01-01

A case of tenth and twelfth nerve compression secondary to a bony exostosis of the first cervical vertebra is described. This uncommon phenomenon serves to outline the importance of imaging the course of a cranial nerve when no intracranial abnormality is demonstrable on CT or MRI. The radiologic features of spinal osteochondromas are reviewed. (orig.)

Evaluation of high-density, multi-contact nerve cuffs for activation of grasp muscles in monkeys

Science.gov (United States)

Brill, N. A.; Naufel, S. N.; Polasek, K.; Ethier, C.; Cheesborough, J.; Agnew, S.; Miller, L. E.; Tyler, D. J.

2018-06-01

Objective. The objective of this work was to evaluate whether nerve cuffs can selectively activate hand muscles for functional electrical stimulation (FES). FES typically involves identifying and implanting electrodes in many individual muscles, but nerve cuffs only require implantation at a single site around the nerve. This method is surgically more attractive. Nerve cuffs may also more effectively stimulate intrinsic hand muscles, which are difficult to implant and stimulate without spillover to adjacent muscles. Approach. To evaluate its ability to selectively activate muscles, we implanted and tested the flat interface nerve electrode (FINE), which is designed to selectively stimulate peripheral nerves that innervate multiple muscles (Tyler and Durand 2002 IEEE Trans. Neural Syst. Rehabil. Eng. 10 294-303). We implanted FINEs on the nerves and bipolar intramuscular wires for recording compound muscle action potentials (CMAPs) from up to 20 muscles in each arm of six monkeys. We then collected recruitment curves while the animals were anesthetized. Main result. A single FINE implanted on an upper extremity nerve in the monkey can selectively activate muscles or small groups of muscles to produce multiple, independent hand functions. Significance. FINE cuffs can serve as a viable supplement to intramuscular electrodes in FES systems, where they can better activate intrinsic and extrinsic muscles with lower currents and less extensive surgery.

Assessment of neurovascular compression in patients with trigeminal neuralgia with a boundary fusion three-dimensional magnetic resonance cisternogram/angiogram

International Nuclear Information System (INIS)

Satoh, Toru; Omi, Megumi; Ohsako, Chika; Onoda, Keisuke; Date, Isao

2007-01-01

Precise assessment of the complex nerve-vessel relationship at the root entry zone (REZ) of the trigeminal nerve is useful for the planning of the microvascular decompression (MVD) in patients with trigeminal neuralgia. We have applied a boundary imaging of fusion three-dimensional (3D) magnetic resonance (MR) cisternogram/angiogram. The boundary imaging allows virtual assessment of the spatial relationship of the neurovascular compression at the REZ of the trigeminal nerve. The boundary images depicted complex anatomical relationship of the offending vessels to the trigeminal nerve REZ. The presence of offending vessels, compressive site, and degree of neurovascular compression were assessed from various viewpoints in the cistern and virtually through the brainstem and trigeminal nerve per se. The 3D visualization of the nerve-vessel relationship with fusion images was consistent with the intraoperative findings. The boundary fusion 3D MR cisternogram/angiogram may prove a useful adjunct for the diagnosis and decision-marking process to execute the MVD in patients with trigeminal neuralgia. (author)

Subperiosteal hematoma from peribulbar block during cataract surgery leading to optic nerve compression in a patient with parahemophilia

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Khokhar S

2015-12-01

Full Text Available Sudarshan Khokhar,1 Bhagabat Nayak,1 Bharat Patil,1 Milind Devidas Changole,1 Gautam Sinha,1 Reetika Sharma,1 Lipika Nayak2 1Dr RP Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India; 2Department of Pediatrics, Loknayak Hospital, Maulana Azad Medical College, Delhi, India Abstract: A 17-year-old male presented with gradual painless diminution of vision since childhood. Slit lamp examination revealed both eyes having congenital cataract. Right eye lens aspiration was performed but was uneventful, and he prepared for left eye surgery after 7 days. Immediately after giving a peribulbar block, a complete akinesia, tight eyelids, and stony hard eyeball was noted. An abaxial proptosis of 7 mm was noted. Lateral canthotomy and inferior cantholysis were done and proptosis reduced to 5 mm. Bleeding time–clotting time was normal. Proptosis worsened to 8 mm the next day. Contrast-enhanced computed tomography scan showed inferolateral subperiosteal hematoma, but drainage could not be performed due to prolonged prothrombin time and activated prothrombin time. Fresh frozen plasma was transfused. Tarsorrhaphy was performed for exposure keratopathy after his coagulation profile became normal. Hematology evaluation after 2 weeks detected factor V deficiency, and was diagnosed as Owren's disease or parahemophilia. Keywords: peribulbar block, hematoma, subperiosteal, parahemophilia, optic nerve compression

Middle ear osteoma causing progressive facial nerve weakness: a case report.

Science.gov (United States)

Curtis, Kate; Bance, Manohar; Carter, Michael; Hong, Paul

2014-09-18

Facial nerve weakness is most commonly due to Bell's palsy or cerebrovascular accidents. Rarely, middle ear tumor presents with facial nerve dysfunction. We report a very unusual case of middle ear osteoma in a 49-year-old Caucasian woman causing progressive facial nerve deficit. A subtle middle ear lesion was observed on otoscopy and computed tomographic images demonstrated an osseous middle ear tumor. Complete surgical excision resulted in the partial recovery of facial nerve function. Facial nerve dysfunction is rarely caused by middle ear tumors. The weakness is typically due to a compressive effect on the middle ear portion of the facial nerve. Early recognition is crucial since removal of these lesions may lead to the recuperation of facial nerve function.

Anterior Inferior Cerebellar Arteries Juxtaposed with the Internal Acoustic Meatus and Their Relationship to the Cranial Nerve VII/VIII Complex.

Science.gov (United States)

Alonso, Fernando; Kassem, Mohammad W; Iwanaga, Joe; Oskouian, Rod J; Loukas, Marios; Demerdash, Amin; Tubbs, R Shane

2017-08-16

Vascular loops in the cerebellopontine angle (CPA) and their relationship to cranial nerves have been used to explain neurological symptoms. The anterior inferior cerebellar artery (AICA) has variable branches producing vascular loops that can compress the facial cranial nerve (CN) VII and vestibulocochlear (CN VIII) nerves. AICA compression of the facial-vestibulocochlear nerve complex can lead to various clinical presentations, including hemifacial spasm (HFS), tinnitus, and hemiataxia. The formation of arterial loops inside or outside of the internal auditory meatus (IAM) can cause abutment or compression of CN VII and CN VIII. Twenty-five (50 sides) fresh adult cadavers underwent dissection of the cerebellopontine angle in the supine position. In regard to relationships between the AICA and the nerves of the facial/vestibulocochlear complex, 33 arteries (66%) traveled in a plane between the facial/nervus intermedius nerves and the cochlear and vestibular nerves. Five arteries (10%) traveled below the CN VII/VIII complex, six (12%) traveled posterior to the nerve complex, four (8%) formed a semi-circle around the upper half of the nerve complex, and two (4%) traveled between and partially separated the nervus intermedius and facial nerve proper. Our study found that the majority of AICA will travel in a plane between the facial/nervus intermedius nerves and the cochlear and vestibular nerves. Although the relationship between the AICA and porus acusticus and AICA and the nerves of the CN VII/VIII complex are variable, based on our findings, some themes exist. Surgeons should consider these with approaches to the cerebellopontine angle.

Relief of fecal incontinence by sacral nerve stimulation linked to focal brain activation

DEFF Research Database (Denmark)

Lundby, Lilli; Møller, Arne; Buntzen, Steen

2011-01-01

This study aimed to test the hypothesis that sacral nerve stimulation affects afferent vagal projections to the central nervous system associated with frontal cortex activation in patients with fecal incontinence.......This study aimed to test the hypothesis that sacral nerve stimulation affects afferent vagal projections to the central nervous system associated with frontal cortex activation in patients with fecal incontinence....

Compressed air injection technique to standardize block injection pressures.

Science.gov (United States)

Tsui, Ban C H; Li, Lisa X Y; Pillay, Jennifer J

2006-11-01

Presently, no standardized technique exists to monitor injection pressures during peripheral nerve blocks. Our objective was to determine if a compressed air injection technique, using an in vitro model based on Boyle's law and typical regional anesthesia equipment, could consistently maintain injection pressures below a 1293 mmHg level associated with clinically significant nerve injury. Injection pressures for 20 and 30 mL syringes with various needle sizes (18G, 20G, 21G, 22G, and 24G) were measured in a closed system. A set volume of air was aspirated into a saline-filled syringe and then compressed and maintained at various percentages while pressure was measured. The needle was inserted into the injection port of a pressure sensor, which had attached extension tubing with an injection plug clamped "off". Using linear regression with all data points, the pressure value and 99% confidence interval (CI) at 50% air compression was estimated. The linearity of Boyle's law was demonstrated with a high correlation, r = 0.99, and a slope of 0.984 (99% CI: 0.967-1.001). The net pressure generated at 50% compression was estimated as 744.8 mmHg, with the 99% CI between 729.6 and 760.0 mmHg. The various syringe/needle combinations had similar results. By creating and maintaining syringe air compression at 50% or less, injection pressures will be substantially below the 1293 mmHg threshold considered to be an associated risk factor for clinically significant nerve injury. This technique may allow simple, real-time and objective monitoring during local anesthetic injections while inherently reducing injection speed.

Electro-mechanical response of a 3D nerve bundle model to mechanical loads leading to axonal injury.

Science.gov (United States)

Cinelli, I; Destrade, M; Duffy, M; McHugh, P

2018-03-01

Traumatic brain injuries and damage are major causes of death and disability. We propose a 3D fully coupled electro-mechanical model of a nerve bundle to investigate the electrophysiological impairments due to trauma at the cellular level. The coupling is based on a thermal analogy of the neural electrical activity by using the finite element software Abaqus CAE 6.13-3. The model includes a real-time coupling, modulated threshold for spiking activation, and independent alteration of the electrical properties for each 3-layer fibre within a nerve bundle as a function of strain. Results of the coupled electro-mechanical model are validated with previously published experimental results of damaged axons. Here, the cases of compression and tension are simulated to induce (mild, moderate, and severe) damage at the nerve membrane of a nerve bundle, made of 4 fibres. Changes in strain, stress distribution, and neural activity are investigated for myelinated and unmyelinated nerve fibres, by considering the cases of an intact and of a traumatised nerve membrane. A fully coupled electro-mechanical modelling approach is established to provide insights into crucial aspects of neural activity at the cellular level due to traumatic brain injury. One of the key findings is the 3D distribution of residual stresses and strains at the membrane of each fibre due to mechanically induced electrophysiological impairments, and its impact on signal transmission. Copyright © 2017 John Wiley & Sons, Ltd.

Renaut bodies in nerves of the trunk of the African elephant, Loxodonta africana.

Science.gov (United States)

Witter, Kirsti; Egger, Gunter F; Boeck, Peter

2007-05-01

Renaut bodies are loosely textured, cell-sparse structures in the subperineurial space of peripheral nerves, frequently found at sites of nerve entrapment. The trunk of the elephant is a mobile, richly innervated organ, which serves for food gathering, object grasping and as a tactile organ. These functions of the trunk lead to distortion and mechanical compression of its nerves, which can therefore be expected to contain numerous Renaut bodies. Samples of the trunk wall of an adult African elephant (Loxodonta africana) were examined histologically using conventional staining methods, immunohistochemistry, and lectin histochemistry. Architecture of nerve plexuses and occurrence of Renaut bodies in the elephant trunk were compared with those in tissues surrounding the nasal vestibule of the pig. Prominent nerve plexuses were found in all layers of the elephant trunk. Almost all (81%) nerve profiles contained Renaut bodies, a basophilic, discrete subperineurial layer resembling cushions around the nerve core. In contrast, Renaut bodies were seen in only 15% of nerve profiles in the porcine nasal vestibule. Within Renaut bodies, fusiform fibroblasts and round, ruff-like cells were placed into a matrix of acidic glycosaminoglycans with delicate collagen and very few reticular fibers. The turgor of this matrix is thought to protect nerves against compression and shearing strain. Renaut bodies are readily stained with alcian blue (pH 2.5) favorably in combination with immunohistochemical markers of nerve fibers. They should be regarded as a physiological response to repeated mechanical insults and are distinct from pathological alterations. alterations. (c) 2007 Wiley-Liss, Inc.

Nerve Wrapping of the Sciatic Nerve With Acellular Dermal Matrix in Chronic Complete Proximal Hamstring Ruptures and Ischial Apophyseal Avulsion Fractures

Science.gov (United States)

Haus, Brian M.; Arora, Danny; Upton, Joseph; Micheli, Lyle J.

2016-01-01

Background: Patients with chronic injuries of the proximal hamstring can develop significant impairment because of weakness of the hamstring muscles, sciatic nerve compression from scar formation, or myositis ossificans. Purpose: To describe the surgical outcomes of patients with chronic injury of the proximal hamstrings who were treated with hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Study Design: Retrospective case series; Level of evidence, 4. Methods: Fifteen consecutive patients with a diagnosis of chronic complete proximal hamstring rupture or chronic ischial tuberosity apophyseal avulsion fracture (mean age, 39.67 years; range, 14-69 years) were treated with proximal hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Nine patients had preoperative sciatica, and 6 did not. Retrospective chart review recorded clinical outcomes measured by the degree of pain relief, the rate of return to activities, and associated postoperative complications. Results: All 15 patients were followed in the postoperative period for an average of 16.6 months. Postoperatively, there were 4 cases of transient sciatic nerve neurapraxia. Four patients (26%) required postoperative betamethasone sodium phosphate (Celestone Soluspan) injectable suspension USP 6 mg/mL. Among the 9 patients with preoperative sciatica, 6 (66%) had a good or excellent outcome and were able to return to their respective activities/sports; 3 (33%) had persistent chronic pain. One of these had persistent sciatic neuropathy that required 2 surgical reexplorations and scar excision after development of recurrent extraneural scar formation. Among the 6 without preoperative sciatica, 100% had a good or excellent outcomes and 83% returned to their respective activities/sports. Better outcomes were observed in younger patients, as the 3 cases of persistent chronic sciatic pain were in patients older than 45

Ultrasonographic evaluation of the iatrogenic peripheral nerve injuries in upper extremity

International Nuclear Information System (INIS)

Karabay, Nuri; Toros, Tulgar; Ademoglu, Yalcin; Ada, Sait

2010-01-01

The aim of our study is to assess the efficiency of the ultrasonography (US) in the diagnosis of peripheral nerve injury. This study includes nine patients (six radial, one median and two posterior interosseous (PIO) nerves) with peripheral nerve injury diagnosed by clinical and electrophysiological methods in the last 3 years. Preoperatively, an ultrasonographic examination was performed and correlated with physical exam and surgical findings. Five patients, who were diagnosed as peripheral nerve transection by US, underwent surgery. The ultrasonographic findings were concordant with the intraoperative findings. Axonal swelling alone was found in the remaining three patients, who were treated conservatively because of preserved nerve continuity without display of nerve compression. In one patient, we were unable to visualize the nerve due to obesity and soft tissue edema. High-resolution US provide morphological information about the exact location, intensity and extent of the nerve injuries, facilitating the preoperative diagnosis. Thus, US may be a useful method for planning optimal treatment strategy in especially iatrogenic nerve injuries.

Ultrasonographic evaluation of the iatrogenic peripheral nerve injuries in upper extremity

Energy Technology Data Exchange (ETDEWEB)

Karabay, Nuri [Department of Radiology, Hand and Microsurgery and Orthopaedics and Traumatology (EMOT) Hospital, 1418 Sok. No: 14 Kahramanlar, 35230 Izmir (Turkey)], E-mail: nurikarabay@gmail.com; Toros, Tulgar [Department of Orthopaedics and Traumatology, Hand and Microsurgery and Orthopaedics and Traumatology (EMOT) Hospital, 1418 Sok. No: 14 Kahramanlar, 35230 Izmir (Turkey)], E-mail: tulgartoros@yahoo.com; Ademoglu, Yalcin [Department of Orthopaedics and Traumatology, Hand and Microsurgery and Orthopaedics and Traumatology (EMOT) Hospital, 1418 Sok. No: 14 Kahramanlar, 35230 Izmir (Turkey)], E-mail: yalcinademoglu@yahoo.com; Ada, Sait [Department of Orthopaedics and Traumatology, Hand and Microsurgery and Orthopaedics and Traumatology (EMOT) Hospital, 1418 Sok. No: 14 Kahramanlar, 35230 Izmir (Turkey)], E-mail: sait_ada@yahoo.com

2010-02-15

The aim of our study is to assess the efficiency of the ultrasonography (US) in the diagnosis of peripheral nerve injury. This study includes nine patients (six radial, one median and two posterior interosseous (PIO) nerves) with peripheral nerve injury diagnosed by clinical and electrophysiological methods in the last 3 years. Preoperatively, an ultrasonographic examination was performed and correlated with physical exam and surgical findings. Five patients, who were diagnosed as peripheral nerve transection by US, underwent surgery. The ultrasonographic findings were concordant with the intraoperative findings. Axonal swelling alone was found in the remaining three patients, who were treated conservatively because of preserved nerve continuity without display of nerve compression. In one patient, we were unable to visualize the nerve due to obesity and soft tissue edema. High-resolution US provide morphological information about the exact location, intensity and extent of the nerve injuries, facilitating the preoperative diagnosis. Thus, US may be a useful method for planning optimal treatment strategy in especially iatrogenic nerve injuries.

Vagus nerve stimulation for epilepsy activates the vocal folds maximally at therapeutic levels.

NARCIS (Netherlands)

Ardesch, J.J.; Sikken, J.R.; Veltink, Petrus H.; van der Aa, H.E.; Hageman, G.; Buschman, H.P.J.

Purpose Vagus nerve stimulation (VNS) for medically refractory epilepsy can give hoarseness due to stimulation of the recurrent laryngeal nerve. For a group of VNS-therapy users this side-effect interferes severely with their daily activities. Our goal was to investigate the severity of

Posterior cricoarytenoid muscle electrophysiologic changes are predictive of vocal cord paralysis with recurrent laryngeal nerve compressive injury in a canine model.

Science.gov (United States)

Puram, Sidharth V; Chow, Harold; Wu, Che-Wei; Heaton, James T; Kamani, Dipti; Gorti, Gautham; Chiang, Feng Yu; Dionigi, Gianlorenzo; Barczynski, Marcin; Schneider, Rick; Dralle, Henning; Lorenz, Kerstin; Randolph, Gregory W

2016-12-01

Injury to the recurrent laryngeal nerve (RLN) is a dreaded complication of endocrine surgery. Intraoperative neural monitoring (IONM) has been increasingly utilized to assess the functional status of the RLN. Although the posterior cricoarytenoid muscle (PCA) is innervated by the RLN as the abductor of the larynx, PCA electromyography (EMG) is infrequently recorded during IONM and PCA activity after RLN compressive injury remains poorly characterized. Single-subject prospective animal study. We employed a canine model to identify postcricoid EMG correlates of postoperative vocal cord paralysis (VCP). Postcricoid electrode recordings were obtained before and after compressive RLN injury associated with VCP. Normative postcricoid recordings revealed mean amplitude of 1288 microvolt (μV) and latency of 8.2 millisecond (ms) with maximum (1 milliamp [mA]) vagal stimulation, and mean amplitude of 1807 μV and latency of 3.5 ms with maximum (1 mA) RLN stimulation. Following injury that was associated with VCP, there was 62.1% decrement in postcricoid EMG amplitude with maximum vagal stimulation and 80% decrement with maximum RLN stimulation. Threshold stimulation of the vagus increased by 23%, and there was a corresponding 42% decrease in amplitude. For RLN stimulation, latency increased by 17.3% following injury, whereas threshold stimulation increased by 61% with 35.5% decrement in EMG amplitude. Thus, if RLN amplitude decreases by ≥ 80%, with absolute amplitude of ≤ 300 μV or less and latency increase of ≥ 10%, RLN injury is likely associated with VCP. Our results predict postoperative VCP based on postcricoid electromyographic IONM and may guide surgical decision making. NA Laryngoscope, 126:2744-2751, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Three-dimensional short-range MR angiography and multiplanar reconstruction images in the evaluation of neurovascular compression in hemifacial spasm

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Choi, Woo Suk; Kim, Eui Jong; Lee, Jae Gue; Rhee, Bong Arm [Kyunghee Univ. Hospital, Seoul (Korea, Republic of)

1998-08-01

To evaluate the diagnostic efficacy of three-dimensional(3D) short-range MR angiography(MRA) and multiplanar reconstruction(MPR) imaging in hemifacial spasm(HS). Materials and Methods : Two hundreds patients with HS were studied using a 1.5T MRI system with a 3D time-of-flight(TOF) MRA sequence. To reconstruct short-range MRA, 6-10 source images near the 7-8th cranial nerve complex were processed using a maximum-intensity projection technique. In addition, an MPR technique was used to investigate neurovascular compression. We observed the relationship between the root-exit zone(REZ) of the 7th cranial nerve and compressive vessel, and identified the compressive vessels on symptomatic sides. To investigate neurovascular contact, asymptomatic contralateral sides were also evaluated. Results : MRI showed that in 197 of 200 patients there was vascular compression or contact with the facial nerve REZ on symptomatic sides. One of the three remaining patients was suffering from acoustic neurinoma on the symptomatic side, while in two patients there were no definite abnormal findings.Compressive vessels were demonstrated in all 197 patients; 80 cases involved the anterior inferior cerebellar artery(AICA), 74 the posterior cerebellar artery(PICA), 13 the vertebral artery(VA), 16 the VA and AICA, eight the VA and PICA, and six the AICA and PICA. In all 197 patients, compressive vessels were reconstructed on one 3D short-range MRA image without discontinuation from vertebral or basilar arteries. 3D MPR studies provided additional information such as the direction of compression and course of the compressive vessel. In 31 patients there was neurovascular contact on the contralateral side at the 7-8th cranial nerve complex. Conclusion : Inpatients with HS, 3D short-range MRA and MPR images are excellent and very helpful for the investigation of neurovascular compression and the identification of compressive vessels.

Three-dimensional short-range MR angiography and multiplanar reconstruction images in the evaluation of neurovascular compression in hemifacial spasm

International Nuclear Information System (INIS)

Choi, Woo Suk; Kim, Eui Jong; Lee, Jae Gue; Rhee, Bong Arm

1998-01-01

To evaluate the diagnostic efficacy of three-dimensional(3D) short-range MR angiography(MRA) and multiplanar reconstruction(MPR) imaging in hemifacial spasm(HS). Materials and Methods : Two hundreds patients with HS were studied using a 1.5T MRI system with a 3D time-of-flight(TOF) MRA sequence. To reconstruct short-range MRA, 6-10 source images near the 7-8th cranial nerve complex were processed using a maximum-intensity projection technique. In addition, an MPR technique was used to investigate neurovascular compression. We observed the relationship between the root-exit zone(REZ) of the 7th cranial nerve and compressive vessel, and identified the compressive vessels on symptomatic sides. To investigate neurovascular contact, asymptomatic contralateral sides were also evaluated. Results : MRI showed that in 197 of 200 patients there was vascular compression or contact with the facial nerve REZ on symptomatic sides. One of the three remaining patients was suffering from acoustic neurinoma on the symptomatic side, while in two patients there were no definite abnormal findings.Compressive vessels were demonstrated in all 197 patients; 80 cases involved the anterior inferior cerebellar artery(AICA), 74 the posterior cerebellar artery(PICA), 13 the vertebral artery(VA), 16 the VA and AICA, eight the VA and PICA, and six the AICA and PICA. In all 197 patients, compressive vessels were reconstructed on one 3D short-range MRA image without discontinuation from vertebral or basilar arteries. 3D MPR studies provided additional information such as the direction of compression and course of the compressive vessel. In 31 patients there was neurovascular contact on the contralateral side at the 7-8th cranial nerve complex. Conclusion : Inpatients with HS, 3D short-range MRA and MPR images are excellent and very helpful for the investigation of neurovascular compression and the identification of compressive vessels

Facial Nerve Schwannoma Involving Middle Cranial Fossa: When the Unilateral Sensorineural Hearing Loss Guide to the Correct Diagnosis

OpenAIRE

De Stefano, Alessandro; Dispenza, Francesco; Kulamarva, Gautham

2011-01-01

The Facial Nerve Schwannoma is a rare tumor and it seldom involved the middle cranial fossa. Facial nerve schwannoma has various manifestations, including facial palsy but unfortunately facial nerve is very resistant to compression and often facial nerve paralysis or a facial weakness are not present. We present a case of giant facial nerve schwannoma involved the middle cranial fossa without facial nerve paralysis. In these cases the unilateral hearing loss (if present) guide to a correct di...

High-resolution STIR for 3-T MRI of the posterior fossa: visualization of the lower cranial nerves and arteriovenous structures related to neurovascular compression.

Science.gov (United States)

Hiwatashi, Akio; Yoshiura, Takashi; Yamashita, Koji; Kamano, Hironori; Honda, Hiroshi

2012-09-01

Preoperative evaluation of small vessels without contrast material is sometimes difficult in patients with neurovascular compression disease. The purpose of this retrospective study was to evaluate whether 3D STIR MRI could simultaneously depict the lower cranial nerves--fifth through twelfth--and the blood vessels in the posterior fossa. The posterior fossae of 47 adults (26 women, 21 men) without gross pathologic changes were imaged with 3D STIR and turbo spin-echo heavily T2-weighted MRI sequences and with contrast-enhanced turbo field-echo MR angiography (MRA). Visualization of the cranial nerves on STIR images was graded on a 4-point scale and compared with visualization on T2-weighted images. Visualization of the arteries on STIR images was evaluated according to the segments in each artery and compared with that on MRA images. Visualization of the veins on STIR images was also compared with that on MRA images. Statistical analysis was performed with the Mann-Whitney U test. There were no significant differences between STIR and T2-weighted images with respect to visualization of the cranial nerves (p > 0.05). Identified on STIR and MRA images were 94 superior cerebellar arteries, 81 anteroinferior cerebellar arteries, and 79 posteroinferior cerebellar arteries. All veins evaluated were seen on STIR and MRA images. There were no significant differences between STIR and MRA images with respect to visualization of arteries and veins (p > 0.05). High-resolution STIR is a feasible method for simultaneous evaluation of the lower cranial nerves and the vessels in the posterior fossa without the use of contrast material.

Intraneural metastasis of gastric carcinoma leads to sciatic nerve palsy

International Nuclear Information System (INIS)

Ichikawa, Jiro; Matsumoto, Seiichi; Shimoji, Takashi; Tanizawa, Taisuke; Gokita, Tabu; Hayakawa, Keiko; Aoki, Kaoru; Ina, Saori; Kanda, Hiroaki

2012-01-01

Soft tissue metastases, in particular intraneural metastasis, from any carcinomas seldom occur. To our knowledge, no case of sciatic nerve palsy due to intraneural metastasis of gastric carcinoma is reported in the literature. A case is reported of a 82-year old woman with sciatic nerve palsy with intraneural metastasis of gastric carcinoma. Although she had undergone partial gastrectomy with T2b, N0, M0 two years ago and primary site was cured, she developed sciatic nerve palsy from the carcinoma metastasis directly to the nerve. Operative resection and Histological examination revealed poorly differentiated adenocarcinoma, the same as her primary site adenocarcinoma. Sciatica is usually caused by a herniated disc or spinal canal stenosis. Sciatic nerve palsy may be caused by nondiscogenic etiologies that may be either intrapelvic or extrapelvic. It is important to image the entire course of the nerve to distinguish these etiologies quickly. The longer the nerve compression the less likely a palsy will recover. Surgery is a good intervention that simultaneously obtains a tissue diagnosis and decompresses the nerve

Effect of nerve activity on transport of nerve growth factor and dopamine β-hydroxylase antibodies in sympathetic neurones

International Nuclear Information System (INIS)

Lees, G.; Chubb, I.; Freeman, C.; Geffen, L.; Rush, R.

1981-01-01

The effect of nerve activity on the uptake and retrograde transport of nerve growth factor (NGF) and dopamine β-hydroxylase (DBH) antibodies was studied by injecting 125 I-labelled NGF and anti-DBH into the anterior eye chamber of guinea-pigs. Decentralization of the ipsilateral superior cervical ganglion (SCG) had no significant effect on the retrograde transport of either NGF or anti-DBH. Phenoxybenzamine produced a 50% increase in anti-DBH but not NGF accumulation and this effect was prevented by prior decentralization. This demonstrates that NGF is taken up independently of the retrieval of synaptic vesicle components. (Auth.)

Experimental study of brachial plexus and vessel compression: evaluation of combined central and peripheral electrodiagnostic approach.

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Yang, Chaoqun; Xu, Jianguang; Chen, Jie; Li, Shulin; Cao, Yu; Zhu, Yi; Xu, Lei

2017-08-01

We sought to investigate the reliability of a new electrodiagnostic method for identifying Electrodiagnosis of Brachial Plexus & Vessel Compression Syndrome (BPVCS) in rats that involves the application of transcranial electrical stimulation motor evoked potentials (TES-MEPs) combined with peripheral nerve stimulation compound muscle action potentials (PNS-CMAPs). The latencies of the TES-MEP and PNS-CMAP were initially elongated in the 8-week group. The amplitudes of TES-MEP and PNS-CMAP were initially attenuated in the 16-week group. The isolateral amplitude ratio of the TES-MEP to the PNS-CMAP was apparently decreased, and spontaneous activities emerged at 16 weeks postoperatively. Superior and inferior trunk models of BPVCS were created in 72 male Sprague Dawley (SD) rats that were divided into six experimental groups. The latencies, amplitudes and isolateral amplitude ratios of the TES-MEPs and PNS-CMAPs were recorded at different postoperative intervals. Electrophysiological and histological examinations of the rats' compressed brachial plexus nerves were utilized to establish preliminary electrodiagnostic criteria for BPVCS.

A 2-year follow-up survey of 523 cases with peripheral nerve injuries caused by the earthquake in Wenchuan, China

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Chun-qing He

2015-01-01

Full Text Available We performed a 2-year follow-up survey of 523 patients with peripheral nerve injuries caused by the earthquake in Wenchuan, Sichuan Province, China. Nerve injuries were classified into three types: type I injuries were nerve transection injuries, type II injuries were nerve compression injuries, and type III injuries displayed no direct neurological dysfunction due to trauma. In this study, 31 patients had type I injuries involving 41 nerves, 419 had type II injuries involving 823 nerves, and 73 had type III injuries involving 150 nerves. Twenty-two patients had open transection nerve injury. The restoration of peripheral nerve function after different treatments was evaluated. Surgical decompression favorably affected nerve recovery. Physiotherapy was effective for type I and type II nerve injuries, but not substantially for type III nerve injury. Pharmacotherapy had little effect on type II or type III nerve injuries. Targeted decompression surgery and physiotherapy contributed to the effective treatment of nerve transection and compression injuries. The Louisiana State University Health Sciences Center score for nerve injury severity declined with increasing duration of being trapped. In the first year after treatment, the Louisiana State University Health Sciences Center score for grades 3 to 5 nerve injury increased by 28.2% to 81.8%. If scores were still poor (0 or 1 after a 1-year period of treatment, further treatment was not effective.

Laser-activated protein solder for peripheral nerve repair

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Trickett, Rodney I.; Lauto, Antonio; Dawes, Judith M.; Owen, Earl R.

1995-05-01

A 100 micrometers core optical fiber-coupled 75 mW diode laser operating at a wavelength of 800 nm has been used in conjunction with a protein solder to stripe weld severed rat tibial nerves, reducing the long operating time required for microsurgical nerve repair. Welding is produced by selective laser denaturation of the albumin based solder which contains the dye indocyanine green. Operating time for laser soldering was 10 +/- 5 min. (n equals 20) compared to 23 +/- 9 min. (n equals 10) for microsuturing. The laser solder technique resulted in patent welds with a tensile strength of 15 +/- 5 g, while microsutured nerves had a tensile strength of 40 +/- 10 g. Histopathology of the laser soldered nerves, conducted immediately after surgery, displayed solder adhesion to the outer membrane with minimal damage to the inner axons of the nerves. An in vivo study is under way comparing laser solder repaired tibial nerves to conventional microsuture repair. At the time of submission 15 laser soldered nerves and 7 sutured nerves were characterized at 3 months and showed successful regeneration with compound muscle action potentials of 27 +/- 8 mV and 29 +/- 8 mW respectively. A faster, less damaging and long lasting laser based anastomotic technique is presented.

Cranial nerve clock. Part II: functional MR imaging of brain activation during a declarative memory task.

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Weiss, K L; Welsh, R C; Eldevik, P; Bieliauskas, L A; Steinberg, B A

2001-12-01

The authors performed this study to assess brain activation during encoding and successful recall with a declarative memory paradigm that has previously been demonstrated to be effective for teaching students about the cranial nerves. Twenty-four students underwent functional magnetic resonance (MR) imaging during encoding and recall of the name, number, and function of the 12 cranial nerves. The students viewed mnemonic graphic and text slides related to individual nerves, as well as their respective control slides. For the recall paradigm, students were prompted with the numbers 1-12 (test condition) intermixed with the number 14 (control condition). Subjects were tested about their knowledge of cranial nerves outside the MR unit before and after functional MR imaging. Students learned about the cranial nerves while undergoing functional MR imaging (mean post- vs preparadigm score, 8.1 +/- 3.4 [of a possible 12] vs 0.75 +/- 0.94, bilateral prefrontal cortex, left greater than right; P brain activation. Encoding revealed statistically significant activation in the bilateral prefrontal cortex, left greater than right [corrected]; bilateral occipital and parietal associative cortices, parahippocampus region, fusiform gyri, and cerebellum. Successful recall activated the left much more than the right prefrontal, parietal associative, and anterior cingulate cortices; bilateral precuneus and cerebellum; and right more than the left posterior cingulate. A predictable pattern of brain activation at functional MR imaging accompanies the encoding and successful recall of the cranial nerves with this declarative memory paradigm.

Electrodiagnosis and nerve conduction studies.

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Posuniak, E A

1984-08-01

The use of electrodiagnostic techniques in evaluation of complaints in the lower extremities provides an objective method of assessment. A basic understanding of principles of neurophysiology, EMG and NCV methodology, and neuropathology of peripheral nerves greatly enhances physical diagnosis and improves the state of the art in treatment of the lower extremity, especially foot and ankle injuries. Familiarity with the method of reporting electrodiagnostic studies and appreciation of the electromyographer's interpretation of the EMG/NCV studies also reflects an enhanced fund of knowledge, skills, and attitudes as pertains to one's level of professional expertise. Information regarding the etiology of positive sharp waves, fibrillation potentials, fasciculation, and normal motor action potentials and conduction studies serves as a sound basis for the appreciation of the categories of nerve injury. Competence in understanding the degree of axonal or myelin function or dysfunction in a nerve improve one's effectiveness not only in medical/surgical treatment but in prognostication of recovery of function. A review of the entrapment syndromes in the lower extremity with emphasis on tarsal tunnel syndrome summarizes the most common nerve entrapments germane to the practice of podiatry. With regard to tarsal tunnel syndrome, the earliest electrodiagnostic study to suggest compression was reported to be the EMG of the foot and leg muscles, even before prolonged nerve latency was noted.

Laser-activated protein bands for peripheral nerve repair

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Lauto, Antonio; Trickett, Rodney I.; Malik, Richard; Dawes, Judith M.; Owen, Earl R.

1996-01-01

A 100 micrometer core optical fiber-coupled 75 mW diode laser operating at a wavelength of 800 nm has been used in conjunction with a protein solder to stripe weld severed rat tibial nerves, reducing the long operating time required for microsurgical nerve repair. Welding is produced by selective laser denaturation of the protein based solder which contains the dye indocyanine green. Operating time for laser soldering was 10 plus or minus 5 min. (n equals 24) compared to 23 plus or minus 9 min (n equals 13) for microsuturing. The laser solder technique resulted in patent welds with a tensile strength of 15 plus or minus 5 g, while microsutured nerves had a tensile strength of 40 plus or minus 10 g. Histopathology of the laser soldered nerves, conducted immediately after surgery, displayed solder adhesion to the outer membrane with minimal damage to the inner axons of the nerves. An in vivo study, with a total of fifty-seven adult male wistar rats, compared laser solder repaired tibial nerves to conventional microsuture repair. Twenty-four laser soldered nerves and thirteen sutured nerves were characterized at three months and showed successful regeneration with average compound muscle action potentials (CMAP) of 2.4 plus or minus 0.7 mV and 2.7 plus or minus 0.8 mV respectively. Histopathology of the in vivo study, confirmed the comparable regeneration of axons in laser and suture operated nerves. A faster, less damaging and long lasting laser based anastomotic technique is presented.

Suprascapular Nerve: Is It Important in Cuff Pathology?

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Lewis L. Shi

2012-01-01

Full Text Available Suprascapular nerve and rotator cuff function are intimately connected. The incidence of suprascapular neuropathy has been increasing due to improved understanding of the disease entity and detection methods. The nerve dysfunction often results from a traction injury or compression, and a common cause is increased tension on the nerve from retracted rotator cuff tears. Suprascapular neuropathy should be considered as a diagnosis if patients exhibit posterosuperior shoulder pain, atrophy or weakness of supraspinatus and infraspinatus without rotator cuff tear, or massive rotator cuff with retraction. Magnetic resonance imaging and electromyography studies are indicated to evaluate the rotator cuff and function of the nerve. Fluoroscopically guided injections to the suprascapular notch can also be considered as a diagnostic option. Nonoperative treatment of suprascapular neuropathy can be successful, but in the recent decade there is increasing evidence espousing the success of surgical treatment, in particular arthroscopic suprascapular nerve decompression. There is often reliable improvement in shoulder pain, but muscle atrophy recovery is less predictable. More clinical data are needed to determine the role of rotator cuff repair and nerve decompression in the same setting.

Isolated long thoracic nerve paralysis - a rare complication of anterior spinal surgery: a case report

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Ameri Ebrahim

2009-06-01

Full Text Available Abstract Introduction Isolated long thoracic nerve injury causes paralysis of the serratus anterior muscle. Patients with serratus anterior palsy may present with periscapular pain, weakness, limitation of shoulder elevation and scapular winging. Case presentation We present the case of a 23-year-old woman who sustained isolated long thoracic nerve palsy during anterior spinal surgery which caused external compressive force on the nerve. Conclusion During positioning of patients into the lateral decubitus position, the course of the long thoracic nerve must be attended to carefully and the nerve should be protected from any external pressure.

Quantitative comparison of disc rim color in optic nerve atrophy of compressive optic neuropathy and glaucomatous optic neuropathy.

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Nakano, Eri; Hata, Masayuki; Oishi, Akio; Miyamoto, Kazuaki; Uji, Akihito; Fujimoto, Masahiro; Miyata, Manabu; Yoshimura, Nagahisa

2016-08-01

The purpose was to investigate an objective and quantitative method to estimate the redness of the optic disc neuroretinal rim, and to determine the usefulness of this method to differentiate compressive optic neuropathy (CON) from glaucomatous optic neuropathy (GON). In our study there were 126 eyes: 40 with CON, 40 with normal tension glaucoma (NTG), and 46 normal eyes (NOR). Digital color fundus photographs were assessed for the redness of disc rim color using ImageJ software. We separately measured the intensity of red, green, and blue pixels from RGB images. Three disc color indices (DCIs), which indicate the redness intensity, were calculated through existing formulas. All three DCIs of CON were significantly smaller than those of NOR (P  -6 dB), in which the extent of retinal nerve fiber layer thinning is comparable, the DCIs of mild CON were significantly smaller than those of mild NTG (P optic disc color was useful in differentiating early-stage CON from GON and NOR.

Localized hypertrophic neuropathy of the sciatic nerve in children: MRI findings

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Roux, Adrien; Treguier, Catherine; Bruneau, Bertrand; Marin, Franck; Gandon, Yves; Gauvrit, Jean-Yves; Riffaud, Laurent; Violas, Philippe; Michel, Anne

2012-01-01

Localized hypertrophic neuropathy (LHN) of the sciatic nerve in children is a rare condition characterized by a painless neurological deficit in the sciatic nerve territory. To demonstrate the role of MRI using a specific protocol and describe the primary findings in LHN. Imaging in four children (age 2 years to 12 years) is presented. All children presented with lower limb asymmetry. Three had a steppage gait. LHN was confirmed by electrophysiological studies and by MRI of the whole sciatic nerve with a dedicated protocol covering the lumbar spine and the lower limb. There were four direct MRI findings: (1) linear and focal hypertrophy with progressive enlargement of a peripheral nerve or plexus diameter, (2) abnormal hyperintensity of the nerve on T2-weighted images, (3) preserved fascicular configuration, and (4) variable enhancement after intravenous gadolinium administration. In addition there were atrophy and fatty infiltration of innervated muscles. MRI was helpful for determining the extent of lesions and in excluding peripheral nerve compression or tumour. MRI of the whole sciatic nerve is the method of choice for diagnosing LHN of the sciatic nerve. (orig.)

Localized hypertrophic neuropathy of the sciatic nerve in children: MRI findings

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Roux, Adrien; Treguier, Catherine; Bruneau, Bertrand; Marin, Franck; Gandon, Yves; Gauvrit, Jean-Yves [University Hospital, Department of Radiology, Hopital Sud, 16 Boulevard de Bulgarie, BP 90347, Rennes cedex 2 (France); Riffaud, Laurent [University Hospital, Department of Pediatric Neurosurgery, Hopital Sud, Rennes (France); Violas, Philippe [University Hospital, Department of Pediatric Surgery, Hopital Sud, Rennes (France); Michel, Anne [University Hospital, Department of Neurological Functional Explorations, Hopital Sud, Rennes (France)

2012-08-15

Localized hypertrophic neuropathy (LHN) of the sciatic nerve in children is a rare condition characterized by a painless neurological deficit in the sciatic nerve territory. To demonstrate the role of MRI using a specific protocol and describe the primary findings in LHN. Imaging in four children (age 2 years to 12 years) is presented. All children presented with lower limb asymmetry. Three had a steppage gait. LHN was confirmed by electrophysiological studies and by MRI of the whole sciatic nerve with a dedicated protocol covering the lumbar spine and the lower limb. There were four direct MRI findings: (1) linear and focal hypertrophy with progressive enlargement of a peripheral nerve or plexus diameter, (2) abnormal hyperintensity of the nerve on T2-weighted images, (3) preserved fascicular configuration, and (4) variable enhancement after intravenous gadolinium administration. In addition there were atrophy and fatty infiltration of innervated muscles. MRI was helpful for determining the extent of lesions and in excluding peripheral nerve compression or tumour. MRI of the whole sciatic nerve is the method of choice for diagnosing LHN of the sciatic nerve. (orig.)

Facial nerve activity disrupts psychomotor rhythms in the forehead microvasculature.

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Drummond, Peter D; O'Brien, Geraldine

2011-10-28

Forehead blood flow was monitored in seven participants with a unilateral facial nerve lesion during relaxation, respiratory biofeedback and a sad documentary. Vascular waves at 0.1Hz strengthened during respiratory biofeedback, in tune with breathing cycles that also averaged 0.1Hz. In addition, a psychomotor rhythm at 0.15Hz was more prominent in vascular waveforms on the denervated than intact side of the forehead, both before and during relaxation and the sad documentary. These findings suggest that parasympathetic activity in the facial nerve interferes with the psychomotor rhythm in the forehead microvasculature. Copyright © 2011 Elsevier B.V. All rights reserved.

Treatment and Follow Up Outcomes of Patients with Peroneal Nerve Injury: A Single Center Experience

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Yasar Dagistan

2017-01-01

Full Text Available Aim: Trap neuropathy is characterized by compression of the peripheral nerve into fibro osseous channels in trespassing areas of body segments. Peroneal nerve is the most frequently injured nerve in traumatic injuries of the lower extremities. In the present study, we investigated functional results of surgical treatment of patients with peroneal nerve injury who delayed visiting our clinics after the damage; we also aimed to observe the effects of this delay on prognosis. We interpreted postoperative results of the patients with EMG and physical examination findings. Material and Method: Subjects with peroneal nerve damage who visited our clinics between 2012 and 2015 were included in the present study. EMG and muscle motor strength tests were conducted pre and postoperatively for clinical assessment. Results: Of the 16 patients in the study population, 7 were men and 9 were women. The median age of the subjects was 49.6 years (14-77 years. Admission time was 9 months after injury. Causes of the peroneal nerve damage were as follows: prosthesis surgery in 4 (25%, ankle damage in 2 (12.5%, excessive squatting by agriculture workers in 4 (25%, aggressive exercise in 2 (12.5%, bone fracture in 2 (12.5%, and unknown origin in 2 (12.5%. Discussion: Peroneal nerve injury usually occurs by compression of the nerve at the head or neck of the fibula. Results of decompression surgery are usually compromising in non-traumatic nerve palsies. Period of duration between injury and diagnosis and muscular atrophy are main factors associated with success of treatment.

The nerves around the shoulder

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Blum, Alain; Lecocq, Sophie; Louis, Matthias; Wassel, Johnny; Moisei, Andreea; Teixeira, Pedro

2013-01-01

Neuropathies of the shoulder are considered to be entrapment syndromes. They are relatively common, accounting for about 2% of cases of sport-related shoulder pain. Many instances involve suprascapular neuropathy, but the clinical diagnosis is often delayed because of nonspecific symptoms. Classically, EMG is the gold standard investigation but MRI currently reveals muscular abnormality in 50% of cases. Muscle edema, the most characteristic symptom, is nonspecific. In general, the topography of edema, the presence of a lesion compressing the nerve and clinical history contribute to the diagnosis. Although atrophy and fatty degeneration may persist after the disappearance of edema, they are rarely symptomatic. The main differential diagnosis is Parsonage–Turner syndrome. Evidence of a cyst pressing on a nerve may prompt puncture-infiltration guided by ultrasonography or CT-scan

The nerves around the shoulder

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Blum, Alain, E-mail: alain.blum@gmail.com [Service d’Imagerie GUILLOZ, CHU Nancy, Nancy 54000 (France); Lecocq, Sophie; Louis, Matthias; Wassel, Johnny; Moisei, Andreea; Teixeira, Pedro [Service d’Imagerie GUILLOZ, CHU Nancy, Nancy 54000 (France)

2013-01-15

Neuropathies of the shoulder are considered to be entrapment syndromes. They are relatively common, accounting for about 2% of cases of sport-related shoulder pain. Many instances involve suprascapular neuropathy, but the clinical diagnosis is often delayed because of nonspecific symptoms. Classically, EMG is the gold standard investigation but MRI currently reveals muscular abnormality in 50% of cases. Muscle edema, the most characteristic symptom, is nonspecific. In general, the topography of edema, the presence of a lesion compressing the nerve and clinical history contribute to the diagnosis. Although atrophy and fatty degeneration may persist after the disappearance of edema, they are rarely symptomatic. The main differential diagnosis is Parsonage–Turner syndrome. Evidence of a cyst pressing on a nerve may prompt puncture-infiltration guided by ultrasonography or CT-scan.

Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia

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Longhurst, John C.

2013-01-01

Thinly myelinated Aδ-fiber and unmyelinated C-fiber cardiac sympathetic (spinal) sensory nerve fibers are activated during myocardial ischemia to transmit the sensation of angina pectoris. Although recent observations showed that myocardial ischemia increases the concentrations of opioid peptides and that the stimulation of peripheral opioid receptors inhibits chemically induced visceral and somatic nociception, the role of opioids in cardiac spinal afferent signaling during myocardial ischemia has not been studied. The present study tested the hypothesis that peripheral opioid receptors modulate cardiac spinal afferent nerve activity during myocardial ischemia by suppressing the responses of cardiac afferent nerve to ischemic mediators like bradykinin and extracellular ATP. The nerve activity of single unit cardiac afferents was recorded from the left sympathetic chain (T2–T5) in anesthetized cats. Forty-three ischemically sensitive afferent nerves (conduction velocity: 0.32–3.90 m/s) with receptive fields in the left and right ventricles were identified. The responses of these afferent nerves to repeat ischemia or ischemic mediators were further studied in the following protocols. First, epicardial administration of naloxone (8 μmol), a nonselective opioid receptor antagonist, enhanced the responses of eight cardiac afferent nerves to recurrent myocardial ischemia by 62%, whereas epicardial application of vehicle (PBS) did not alter the responses of seven other cardiac afferent nerves to ischemia. Second, naloxone applied to the epicardial surface facilitated the responses of seven cardiac afferent nerves to epicardial ATP by 76%. Third, administration of naloxone enhanced the responses of seven other afferent nerves to bradykinin by 85%. In contrast, in the absence of naloxone, cardiac afferent nerves consistently responded to repeated application of ATP (n = 7) or bradykinin (n = 7). These data suggest that peripheral opioid peptides suppress the

Total Facial Nerve Decompression for Severe Traumatic Facial Nerve Paralysis: A Review of 10 Cases

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Sertac Yetiser

2012-01-01

Full Text Available Management of traumatic facial nerve disorders is challenging. Facial nerve decompression is indicated if 90–95% loss of function is seen at the very early period on ENoG or if there is axonal degeneration on EMG lately with no sign of recovery. Middle cranial or translabyrinthine approach is selected depending on hearing. The aim of this study is to present retrospective review of 10 patients with sudden onset complete facial paralysis after trauma who underwent total facial nerve decompression. Operation time after injury is ranging between 16 and105 days. Excitation threshold, supramaximal stimulation, and amplitude on the paralytic side were worse than at least %85 of the healthy side. Six of 11 patients had HBG-II, one patient had HBG-I, 3 patients had HBG-III, and one patient had HBG-IV recovery. Stretch, compression injuries with disruption of the endoneurial tubules undetectable at the time of surgery and lack of timely decompression may be associated with suboptimal results in our series.

Comparative Evaluation of Chitosan Nerve Guides with Regular or Increased Bendability for Acute and Delayed Peripheral Nerve Repair: A Comprehensive Comparison with Autologous Nerve Grafts and Muscle-in-Vein Grafts.

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Stößel, Maria; Wildhagen, Vivien M; Helmecke, Olaf; Metzen, Jennifer; Pfund, Charlotte B; Freier, Thomas; Haastert-Talini, Kirsten

2018-05-08

Reconstruction of joint-crossing digital nerves requires the application of nerve guides with a much higher flexibility than used for peripheral nerve repair along larger bones. Nevertheless, collapse-resistance should be preserved to avoid secondary damage to the regrowing nerve tissue. In recent years, we presented chitosan nerve guides (CNGs) to be highly supportive for the regeneration of critical gap length peripheral nerve defects in the rat. Now, we evidently increased the bendability of regular CNGs (regCNGs) by developing a wavy wall structure, that is, corrugated CNGs (corrCNGs). In a comprehensive in vivo study, we compared both types of CNGs with clinical gold standard autologous nerve grafts (ANGs) and muscle-in-vein grafts (MVGs) that have recently been highlighted in the literature as a suitable alternative to ANGs. We reconstructed rat sciatic nerves over a critical gap length of 15 mm either immediately upon transection or after a delay period of 45 days. Electrodiagnostic measurements were applied to monitor functional motor recovery at 60, 90, 120, and 150 (only delayed repair) days postreconstruction. Upon explanation, tube properties were analyzed. Furthermore, distal nerve ends were evaluated using histomorphometry, while connective tissue specimens were subjected to immunohistological stainings. After 120 days (acute repair) or 150 days (delayed repair), respectively, compression-stability of regCNGs was slightly increased while it remained stable in corrCNGs. In both substudies, regCNGs and corrCNGs supported functional recovery of distal plantar muscles in a similar way and to a greater extent when compared with MVGs, while ANGs demonstrated the best support of regeneration. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Myocardial adrenergic nerve activity in valvular diseases assessed by iodine-123-metaiodobenzylguanidine myocardial scintigraphy

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Imamura, Yoshihiro; Fukuyama, Takaya

1997-01-01

Iodine-123-metaiodobenzylguanidine (MIBG) imaging was used to assess myocardial adrenergic nerve activity in patients with heart failure. MIBG planar images were obtained in 94 patients. The uptake of MIBG, calculated as the heart-to-mediastinum activity ratio in the immediate image (15 min), showed a significant decrease only in patients with severe heart failure due to cardiomyopathy, but was not changed in those with valvular diseases. Storage and release of MIBG, calculated as the percentage myocardial MIBG washout from 15 min to 4 hours after isotope injection, was substantially accelerated in both patients with cardiomyopathy and valvular diseases in proportion to the severity of heart failure. These data suggest that, in severe heart failure associated with cardiomyopathy, norepinephrine uptake is reduced. Also, myocardial adrenergic nerve activity is accelerated in proportion to the severity of heart failure independent of the underlying cause. MIBG images were analyzed in 20 patients with mitral stenosis with the same methods to clarify whether myocardial adrenergic nerve activity is different in patients with heart failure without left ventricular volume or pressure overload. Myocardial uptake of MIBG did not show any significant difference. The percentage myocardial MIBG washout was increased in patients with severe heart failure. The closest correlation was between myocardial washout and cardiac output. In heart failure due to mitral stenosis, myocardial adrenergic nerve activity is intensified. Decrease in cardiac output associated with mitral stenosis acts as a potent stimulus for this intensification. (author)

Glossopharyngeal neuralgia secondary to vascular compression in a patient with multiple sclerosis: a case report

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Gaitour Emil

2012-07-01

Full Text Available Abstract Introduction Glossopharyngeal neuralgia is an uncommon, painful syndrome, characterized by paroxysms of pain in the sensory distribution of the 9th cranial nerve. Idiopathic glossopharyngeal neuralgia may be due to compression of the glossopharyngeal nerve by adjacent vessels, while secondary glossopharyngeal neuralgia is associated with identifiable lesions affecting the glossopharyngeal nerve at different levels of its neuroanatomic pathway. Glossopharyngeal neuralgia is rare in the general population, but is more common in patients with multiple sclerosis. Case presentation A 56-year-old Caucasian woman with multiple sclerosis and migraine presented to our facility with intermittent lancinating pain to the right of her throat, tongue, and the floor of her mouth that had been occurring for the past year. The pain was intense, sharp, and stabbing, which lasted two to six seconds with radiation to the right ear. Initially, the attacks were infrequent, however, they had become more intense and frequent over time. Our patient reported weight loss, headache, painful swallowing, and the inability to maintain sleep due to painful attacks. A neurological examination revealed a right-handed woman with trigger points in the back of the tongue and throat on the right side. She also had dysphagia, hoarseness, and pain in the distribution of the right glossopharyngeal nerve. Mild right hemiparesis, hyperreflexia, dysmetria, and an ataxic gait were present. A magnetic resonance imaging scan of the brain was consistent with multiple sclerosis and magnetic resonance angiography demonstrated a loop of the posterior inferior cerebellar artery compressing the right glossopharyngeal nerve. She responded satisfactorily to carbamazepine. Microvascular decompression and Gamma Knife® radiosurgery were discussed in case of failure of the medical treatment; however, she declined these options. Conclusions Glossopharyngeal neuralgia in multiple sclerosis may

Traditional Chinese herbal formula relieves snoring by modulating activities of upper airway related nerves in aged rats

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Chung KT

2018-05-01

Full Text Available Kou-Toung Chung,* Chih-Hsiang Hsu,* Ching-Lung Lin, Sheue-Er Wang, Chung-Hsin WuDepartment of Life Science, National Taiwan Normal University, Taipei, Taiwan*These authors contributed equally to this workAim: The present study investigated whether intraperitoneal treatment with the herbal formula B210 ([B210]; a herbal composition of Gastrodia elata and Cinnamomum cassia can reduce snoring in aged rats. Also, we studied possible neural mechanisms involved in B210 treatment and subsequent reduced snoring in rats.Methods and result: We compared pressure and frequency of snoring, activities of phrenic nerve (PNA, activities of recurrent laryngeal nerve (RLNA and activities of hypoglossal nerve (HNA, inspiratory time (TI and expiratory time (TE of PNA, and pre-inspiratory time (Pre-TI of HNA in aged rats between sham and B210 treatment groups (30 mg/mL dissolved in DMSO. We found that aged rats that received B210 treatment had significantly reduced pressure and frequency of snoring than rats who received sham treatment. Also, we observed that aged rats that received B210 treatment had significantly increased PNA, RLNA, and HNA, extended TI and TE of PNA, and prolonged Pre-TI of HNA compared to rats that received sham treatment. In other words, B210 treatment may relieve snoring through modulating activities and breathing time of upper airway related nerves in aged rats.Conclusion: We suggested that the B210 might be a potential herbal formula for snoring remission.Keywords: Chinese herbal medicine, snoring remission, upper airway, phrenic nerve, recurrent laryngeal nerve, hypoglossal nerve

Thoracic Outlet Syndrome

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... tumors that press on nerves, poor posture that causes nerve compression, pregnancy, and repetitive arm and shoulder movements and activity, ... tumors that press on nerves, poor posture that causes nerve compression, pregnancy, and repetitive arm and shoulder movements and activity, ...

External cardiac compression may be harmful in some scenarios of pulseless electrical activity.

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Hogan, T S

2012-10-01

Pulseless electrical activity occurs when organised or semi-organised electrical activity of the heart persists but the product of systemic vascular resistance and the increase in systemic arterial flow generated by the ejection of the left venticular stroke volume is not sufficient to produce a clinically detectable pulse. Pulseless electrical activity encompasses a very heterogeneous variety of severe circulatory shock states ranging in severity from pseudo-cardiac arrest to effective cardiac arrest. Outcomes of cardiopulmonary resuscitation for pulseless electrical activity are generally poor. Impairment of cardiac filling is the limiting factor to cardiac output in many scenarios of pulseless electrical activity, including extreme vasodilatory shock states. There is no evidence that external cardiac compression can increase cardiac output when impaired cardiac filling is the limiting factor to cardiac output. If impaired cardiac filling is the limiting factor to cardiac output and the heart is effectively ejecting all the blood returning to it, then external cardiac compression can only increase cardiac output if it increases venous return and cardiac filling. Repeated cardiac compression asynchronous with the patient's cardiac cycle and raised mean intrathoracic pressure due to chest compression can be expected to reduce rather than to increase cardiac filling and therefore to reduce rather than to increase cardiac output in such circumstances. The hypothesis is proposed that the performance of external cardiac compression will have zero or negative effect on cardiac output in pulseless electrical activity when impaired cardiac filling is the limiting factor to cardiac output. External cardiac compression may be both directly and indirectly harmful to significant sub-groups of patients with pulseless electrical activity. We have neither evidence nor theory to provide comfort that external cardiac compression is not harmful in many scenarios of pulseless

External cardiac compression may be harmful in some scenarios of pulseless electrical activity.

LENUS (Irish Health Repository)

Hogan, T S

2012-10-01

Pulseless electrical activity occurs when organised or semi-organised electrical activity of the heart persists but the product of systemic vascular resistance and the increase in systemic arterial flow generated by the ejection of the left venticular stroke volume is not sufficient to produce a clinically detectable pulse. Pulseless electrical activity encompasses a very heterogeneous variety of severe circulatory shock states ranging in severity from pseudo-cardiac arrest to effective cardiac arrest. Outcomes of cardiopulmonary resuscitation for pulseless electrical activity are generally poor. Impairment of cardiac filling is the limiting factor to cardiac output in many scenarios of pulseless electrical activity, including extreme vasodilatory shock states. There is no evidence that external cardiac compression can increase cardiac output when impaired cardiac filling is the limiting factor to cardiac output. If impaired cardiac filling is the limiting factor to cardiac output and the heart is effectively ejecting all the blood returning to it, then external cardiac compression can only increase cardiac output if it increases venous return and cardiac filling. Repeated cardiac compression asynchronous with the patient\\'s cardiac cycle and raised mean intrathoracic pressure due to chest compression can be expected to reduce rather than to increase cardiac filling and therefore to reduce rather than to increase cardiac output in such circumstances. The hypothesis is proposed that the performance of external cardiac compression will have zero or negative effect on cardiac output in pulseless electrical activity when impaired cardiac filling is the limiting factor to cardiac output. External cardiac compression may be both directly and indirectly harmful to significant sub-groups of patients with pulseless electrical activity. We have neither evidence nor theory to provide comfort that external cardiac compression is not harmful in many scenarios of pulseless

Degenerative Nerve Diseases

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Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many ... viruses. Sometimes the cause is not known. Degenerative nerve diseases include Alzheimer's disease Amyotrophic lateral sclerosis Friedreich's ...

Ultrasound of the sural nerve: Normal anatomy on cadaveric dissection and case series

International Nuclear Information System (INIS)

Belsack, Dries; Jager, Tjeerd; Scafoglieri, Aldo; Vanderdood, Kurt; Van Hedent, Eddy; Vanhoenacker, Filip; Marcelis, Stefaan; De Maeseneer, Michel

2013-01-01

The sural nerve is a small sensory nerve innervating the lateral aspect of the ankle and foot. Clinical symptoms of pathology may present as atypical sensory changes in this region. We present the normal anatomy and ultrasound technique for examination of the sural nerve based on an anatomical dissection, as well as imaging in a normal volunteer. We also present a case series (n = 10) of different conditions of the sural nerve that we encountered based on a review of interesting cases from 4 institutions. The pathological conditions included neuropathy related to stripping or venous laser surgery, compression by abscess, Lyme disease, nerve tumors, traumatic transsection, and encasement by fibrous plaque and edema. Ultrasound with its exquisite resolution is the preferred imaging method for examining the sural nerve in patients with unexplained sensory changes at the lateral aspect of the ankle and foot

Ultrasound of the sural nerve: Normal anatomy on cadaveric dissection and case series

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Belsack, Dries, E-mail: dries.belsack@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Jette, Brussels (Belgium); Jager, Tjeerd, E-mail: tjeerd.jager@asz.be [Department of Radiology, Aalsters Stedelijk Ziekenhuis, Merestraat 80, 9300 Aalst (Belgium); Scafoglieri, Aldo, E-mail: aldo.scafoglieri@vub.ac.be [Department of Experimental Anatomy, Free University Brussels, Laarbeeklaan 103, 1090 Jette (Belgium); Vanderdood, Kurt, E-mail: kvanderd@yahoo.com [Department of Radiology, Maaslandziekenhuis, Dr H van der Hoffplein 1, 6162 Sittard-Geleen, Sittard (Netherlands); Van Hedent, Eddy, E-mail: eddy.vanhedent@asz.be [Department of Radiology, Aalsters Stedelijk Ziekenhuis, Merestraat 80, 9300 Aalst (Belgium); Vanhoenacker, Filip, E-mail: filip.vanhoenacker@telenet.be [Department of Radiology, AZ Sint-Maarten, Duffel-Mechelen, Rooienberg 25, 2570 Duffel (Belgium); Marcelis, Stefaan, E-mail: stefaan.marcelis@sintandriesstielt.be [Department of Radiology, Sint Andriesziekenhuis, Krommewalstraat 11, 8700 Tielt (Belgium); De Maeseneer, Michel, E-mail: michel.demaeseneer@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Jette, Brussels (Belgium)

2013-11-01

The sural nerve is a small sensory nerve innervating the lateral aspect of the ankle and foot. Clinical symptoms of pathology may present as atypical sensory changes in this region. We present the normal anatomy and ultrasound technique for examination of the sural nerve based on an anatomical dissection, as well as imaging in a normal volunteer. We also present a case series (n = 10) of different conditions of the sural nerve that we encountered based on a review of interesting cases from 4 institutions. The pathological conditions included neuropathy related to stripping or venous laser surgery, compression by abscess, Lyme disease, nerve tumors, traumatic transsection, and encasement by fibrous plaque and edema. Ultrasound with its exquisite resolution is the preferred imaging method for examining the sural nerve in patients with unexplained sensory changes at the lateral aspect of the ankle and foot.

Anatomical variations of pronator teres muscle: predispositional role for nerve entrapment

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Edie Benedito Caetano

Full Text Available ABSTRACT OBJECTIVE: To assess the anatomical variations of the pronator teres muscle (PTM and its implication in the compression of the median nerve, which passes through the humeral and ulnar heads of the PTM. METHODS: For the present study, 100 upper limbs from human cadavers from the anatomy laboratory were dissected. Forty-six specimens were male and four, female, whose aged ranged from 28 to 77 years; 27 were white and 23, non-white. A pilot study consisting of six hands from three fresh cadaver dissections was conducted to familiarize the authors with the local anatomy; these were not included in the present study. RESULTS: The humeral and ulnar heads of PTM were present in 86 limbs. In 72 out of the 86 limbs, the median nerve was positioned between the two heads of the PTM; in 11, it passed through the muscle belly of ulnar head of the PTM, and in three, posteriorly to both heads of the PTM. When both heads were present, the median nerve was not observed as passing through the muscle belly of the humeral head of PTM. In 14 out of the 100 dissected limbs, the ulnar head of the PTM was not observed; in this situation, the median nerve was positioned posteriorly to the humeral head in 11 limbs, and passed through the humeral head in three. In 17 limbs, the ulnar head of PTM was little developed, with a fibrous band originating from the ulnar coronoid process, associated with a distal muscle component near the union with the humeral head. In four limbs, the ulnar head of the MPR was represented by a fibrous band. In both limbs of one cadaver, a fibrous band was observed between the supinator muscle and the humeral head of the PTM, passing over median nerve. CONCLUSION: The results suggest that these anatomical variations in relationship median nerve and PTM are potential factors for median nerve compression, as they narrow the space through which the median nerve passes.

A study of retrograde degeneration of median nerve forearm ...

African Journals Online (AJOL)

Introduction: Carpal tunnel syndrome (CTS) is a disorder of the hand which results from compression of the median nerve within its fibro-osseous tunnel at the wrist. The slowing in the forearm motor conduction velocity suggests the presence of retrograde degeneration. Existing studies conflict regarding a correlation ...

Neuroprotective effect of lurasidone via antagonist activities on histamine in a rat model of cranial nerve involvement.

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He, Baoming; Yu, Liang; Li, Suping; Xu, Fei; Yang, Lili; Ma, Shuai; Guo, Yi

2018-04-01

Cranial nerve involvement frequently involves neuron damage and often leads to psychiatric disorder caused by multiple inducements. Lurasidone is a novel antipsychotic agent approved for the treatment of cranial nerve involvement and a number of mental health conditions in several countries. In the present study, the neuroprotective effect of lurasidone by antagonist activities on histamine was investigated in a rat model of cranial nerve involvement. The antagonist activities of lurasidone on serotonin 5‑HT7, serotonin 5‑HT2A, serotonin 5‑HT1A and serotonin 5‑HT6 were analyzed, and the preclinical therapeutic effects of lurasidone were examined in a rat model of cranial nerve involvement. The safety, maximum tolerated dose (MTD) and preliminary antitumor activity of lurasidone were also assessed in the cranial nerve involvement model. The therapeutic dose of lurasidone was 0.32 mg once daily, administered continuously in 14‑day cycles. The results of the present study found that the preclinical prescriptions induced positive behavioral responses following treatment with lurasidone. The MTD was identified as a once daily administration of 0.32 mg lurasidone. Long‑term treatment with lurasidone for cranial nerve involvement was shown to improve the therapeutic effects and reduce anxiety in the experimental rats. In addition, treatment with lurasidone did not affect body weight. The expression of the language competence protein, Forkhead‑BOX P2, was increased, and the levels of neuroprotective SxIP motif and microtubule end‑binding protein were increased in the hippocampal cells of rats with cranial nerve involvement treated with lurasidone. Lurasidone therapy reinforced memory capability and decreased anxiety. Taken together, lurasidone treatment appeared to protect against language disturbances associated with negative and cognitive impairment in the rat model of cranial nerve involvement, providing a basis for its use in the clinical treatment of

Clarification of Eponymous Anatomical Terminology: Structures Named After Dr Geoffrey V. Osborne That Compress the Ulnar Nerve at the Elbow.

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Wali, Arvin R; Gabel, Brandon; Mitwalli, Madhawi; Tubbs, R Shane; Brown, Justin M

2017-05-01

In 1957, Dr Geoffrey Osborne described a structure between the medial epicondyle and the olecranon that placed excessive pressure on the ulnar nerve. Three terms associated with such structures have emerged: Osborne's band, Osborne's ligament, and Osborne's fascia. As anatomical language moves away from eponymous terminology for descriptive, consistent nomenclature, we find discrepancies in the use of anatomic terms. This review clarifies the definitions of the above 3 terms. We conducted an extensive electronic search via PubMed and Google Scholar to identify key anatomical and surgical texts that describe ulnar nerve compression at the elbow. We searched the following terms separately and in combination: "Osborne's band," "Osborne's ligament," and "Osborne's fascia." A total of 36 papers were included from 1957 to 2016. Osborne's band, Osborne's ligament, and Osborne's fascia were found to inconsistently describe the etiology of ulnar neuritis, referring either to the connective tissue between the 2 heads of the flexor carpi ulnaris muscle as described by Dr Osborne or to the anatomically distinct fibrous tissue between the olecranon process of the ulna and the medial epicondyle of the humerus. The use of eponymous terms to describe ulnar pathology of the elbow remains common, and although these terms allude to the rich history of surgical anatomy, these nonspecific descriptions lead to inconsistencies. As Osborne's band, Osborne's ligament, and Osborne's fascia are not used consistently across the literature, this research demonstrates the need for improved terminology to provide reliable interpretation of these terms among surgeons.

Which nerve conduction parameters can predict spontaneous electromyographic activity in carpal tunnel syndrome?

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Chang, Chia-Wei; Lee, Wei-Ju; Liao, Yi-Chu; Chang, Ming-Hong

2013-11-01

We investigate electrodiagnostic markers to determine which parameters are the best predictors of spontaneous electromyographic (EMG) activity in carpal tunnel syndrome (CTS). We enrolled 229 patients with clinically proven and nerve conduction study (NCS)-proven CTS, as well as 100 normal control subjects. All subjects were evaluated using electrodiagnostic techniques, including median distal sensory latencies (DSLs), sensory nerve action potentials (SNAPs), distal motor latencies (DMLs), compound muscle action potentials (CMAPs), forearm median nerve conduction velocities (FMCVs) and wrist-palm motor conduction velocities (W-P MCVs). All CTS patients underwent EMG examination of the abductor pollicis brevis (APB) muscle, and the presence or absence of spontaneous EMG activities was recorded. Normal limits were determined by calculating the means ± 2 standard deviations from the control data. Associations between parameters from the NCS and EMG findings were investigated. In patients with clinically diagnosed CTS, abnormal median CMAP amplitudes were the best predictors of spontaneous activity during EMG examination (p95% (positive predictive rate >95%). If the median CMAP amplitude was higher than the normal limit (>4.9 mV), the rate of no spontaneous EMG activity was >94% (negative predictive rate >94%). An abnormal SNAP amplitude was the second best predictor of spontaneous EMG activity (p<0.001; OR 4.13; 95% CI 2.16-7.90), and an abnormal FMCV was the third best predictor (p=0.01; OR 2.10; 95% CI 1.20-3.67). No other nerve conduction parameters had significant power to predict spontaneous activity upon EMG examination. The CMAP amplitudes of the APB are the most powerful predictors of the occurrence of spontaneous EMG activity. Low CMAP amplitudes are strongly associated with spontaneous activity, whereas high CMAP amplitude are less associated with spontaneous activity, implying that needle EMG examination should be recommended for the detection of

Iliopsoas bursitis with compression of the common femoral vein resulting in acute lower leg edema

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Hwang, Seung Bae; Kwak, Hyo Sung; Han, Young Min; Lee, Sang Yong; Jeong, Yeon Jun [Chonbuk National University Medical School, Chonju (Korea, Republic of)

2006-08-15

The clinical manifestations related to iliopsoas bursitis can vary due to compression of the adjacent structure such as the common femoral vein, nerve and bladder. We report here on a rare case of iliopsoas bursitis with compression of the common femoral vein that resulted in acute lower leg edema.

Iliopsoas bursitis with compression of the common femoral vein resulting in acute lower leg edema

International Nuclear Information System (INIS)

Hwang, Seung Bae; Kwak, Hyo Sung; Han, Young Min; Lee, Sang Yong; Jeong, Yeon Jun

2006-01-01

The clinical manifestations related to iliopsoas bursitis can vary due to compression of the adjacent structure such as the common femoral vein, nerve and bladder. We report here on a rare case of iliopsoas bursitis with compression of the common femoral vein that resulted in acute lower leg edema

Ulnar nerve entrapment complicating radial head excision

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Kevin Parfait Bienvenu Bouhelo-Pam

Full Text Available Introduction: Several mechanisms are involved in ischemia or mechanical compression of ulnar nerve at the elbow. Presentation of case: We hereby present the case of a road accident victim, who received a radial head excision for an isolated fracture of the radial head and complicated by onset of cubital tunnel syndrome. This outcome could be the consequence of an iatrogenic valgus of the elbow due to excision of the radial head. Hitherto the surgical treatment of choice it is gradually been abandoned due to development of radial head implant arthroplasty. However, this management option is still being performed in some rural centers with low resources. Discussion: The radial head plays an important role in the stability of the elbow and his iatrogenic deformity can be complicated by cubital tunnel syndrome. Conclusion: An ulnar nerve release was performed with favorable outcome. Keywords: Cubital tunnel syndrome, Peripheral nerve palsy, Radial head excision, Elbow valgus

[A case of medulla oblongata compression by tortuous vertebral arteries presenting with spastic quadriplegia].

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Kamada, Takashi; Tateishi, Takahisa; Yamashita, Tamayo; Nagata, Shinji; Ohyagi, Yasumasa; Kira, Jun-Ichi

2013-01-01

We report a 58-year-old man showing spastic paraparesis due to medulla oblongata compression by tortuous vertebral arteries. He noticed weakness of both legs and gait disturbance at the age of 58 years and his symptoms progressively worsened during the following several months. General physical findings were normal. Blood pressure was normal and there were no signs of arteriosclerosis. Neurological examination on admission revealed lower-limb-dominant spasticity in all four extremities, lower-limb weakness, hyperreflexia in all extremities with positive Wartenberg's, Babinski's and Chaddock's signs, mild hypesthesia and hypopallesthesia in both lower limbs, and spastic gait. Cranial nerves were all normal. Serum was negative for antibodies against human T-cell lymphotropic virus-1 antibody. Nerve conduction and needle electromyographic studies of all four limbs revealed normal findings. Cervical, thoracic and lumbo-sacral magnetic resonance imaging (MRI) findings were all normal. Brain MRI and magnetic resonance angiography demonstrated bilateral tortuous vertebral arteries compressing the medulla oblongata. Neurovascular decompression of the right vertebral artery was performed because compression of the right side was more severe than that of the left side. Post-operative MRI revealed outward translocation of the right vertebral artery and relieved compression of the medulla oblongata on the right side. The patient's symptoms and neurological findings improved gradually after the operation. Bilateral pyramidal tract signs without cranial nerve dysfunction due to compression of the medulla oblongata by tortuous vertebral arteries are extremely rare and clinically indistinguishable from hereditary spastic paraplegia (HSP). Although we did not perform a genetic test for HSP, we consider that the spastic paraparesis and mild lower-limb hypesthesia were caused by compression of the medulla oblongata by bilateral tortuous vertebral arteries based on the post

Orbital apex cyst: a rare cause of compressive optic neuropathy post-functional endoscopic sinus surgery

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Koh YN

2017-07-01

Full Text Available Yi Ni Koh,1,2 Shu Fen Ho,2 Letchumanan Pathma,3 Harvinder Singh,3 Embong Zunaina1 1Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia; 2Department of Ophthalmology, 3Department of Otorhinolaryngology, Hospital Raja Permaisuri Bainun, Ipoh, Perak, Malaysia Abstract: There are various causes that can lead to compressive optic neuropathy. We present here orbital apex cyst as an unusual cause of compressive optic neuropathy in a 49-year-old male. He presented with 2 weeks painless loss of vision in the left eye with left-sided headache. He had had left functional endoscopic sinus surgery for left nasal polyps 4 years earlier. Magnetic resonance imaging of brain and orbit revealed a left discrete orbital nodule, possibly orbital cyst or mucocele, which was compressing on the left optic nerve. Left eye vision improved markedly from hand movement to 6/36 pinhole 6/18 after initiation of intravenous dexamethasone. A subsequent endoscopic endonasal left optic nerve decompression found the orbital nodule lesion to be an orbital cyst. Marsupialization was performed instead of excision, as the cyst ruptured intraoperatively. Postoperative vision improved to 6/7.5 with normal optic nerve function postoperatively. Possible cause of orbital apex cyst is discussed. Keywords: orbital cyst, compressive optic neuropathy, functional endoscopic sinus surgery

Schwannoma originating from lower cranial nerves: report of 4 cases.

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Oyama, Hirofumi; Kito, Akira; Maki, Hideki; Hattori, Kenichi; Noda, Tomoyuki; Wada, Kentaro

2012-02-01

Four cases of schwannoma originating from the lower cranial nerves are presented. Case 1 is a schwannoma of the vagus nerve in the parapharyngeal space. The operation was performed by the transcervical approach. Although the tumor capsule was not dissected from the vagus nerve, hoarseness and dysphagia happened transiently after the operation. Case 2 is a schwannoma in the jugular foramen. The operation was performed by the infralabyrinthine approach. Although only the intracapsular tumor was enucleated, facial palsy, hoarseness, dysphagia and paresis of the deltoid muscle occurred transiently after the operation. The patient's hearing had also slightly deteriorated. Case 3 is a dumbbell-typed schwannoma originating from the hypoglossal nerve. The hypoglossal canal was markedly enlarged by the tumor. As the hypoglossal nerves were embedded in the tumor, the tumor around the hypoglossal nerves was not resected. The tumor was significantly enlarged for a while after stereotactic irradiation. Case 4 is an intracranial cystic schwannoma originating from the IXth or Xth cranial nerves. The tumor was resected through the cerebello-medullary fissure. The tumor capsule attached to the brain stem was not removed. Hoarseness and dysphagia happened transiently after the operation. Cranial nerve palsy readily occurs after the removal of the schwannoma originating from the lower cranial nerves. Mechanical injury caused by retraction, extension and compression of the nerve and heat injury during the drilling of the petrous bone should be cautiously avoided.

In vitro efficacy of a gene-activated nerve guidance conduit incorporating non-viral PEI-pDNA nanoparticles carrying genes encoding for NGF, GDNF and c-Jun.

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Lackington, William A; Raftery, Rosanne M; O'Brien, Fergal J

2018-06-07

Despite the success of tissue engineered nerve guidance conduits (NGCs) for the treatment of small peripheral nerve injuries, autografts remain the clinical gold standard for larger injuries. The delivery of neurotrophic factors from conduits might enhance repair for more effective treatment of larger injuries but the efficacy of such systems is dependent on a safe, effective platform for controlled and localised therapeutic delivery. Gene therapy might offer an innovative approach to control the timing, release and level of neurotrophic factor production by directing cells to transiently sustain therapeutic protein production in situ. In this study, a gene-activated NGC was developed by incorporating non-viral polyethyleneimine-plasmid DNA (PEI-pDNA) nanoparticles (N/P 7 ratio, 2μg dose) with the pDNA encoding for nerve growth factor (NGF), glial derived neurotrophic factor (GDNF) or the transcription factor c-Jun. The physicochemical properties of PEI-pDNA nanoparticles, morphology, size and charge, were shown to be suitable for gene delivery and demonstrated high Schwann cell transfection efficiency (60±13%) in vitro. While all three genes showed therapeutic potential in terms of enhancing neurotrophic cytokine production while promoting neurite outgrowth, delivery of the gene encoding for c-Jun showed the greatest capacity to enhance regenerative cellular processes in vitro. Ultimately, this gene-activated NGC construct was shown to be capable of transfecting both Schwann cells (S42 cells) and neuronal cells (PC12 and dorsal root ganglia) in vitro, demonstrating potential for future therapeutic applications in vivo. The basic requirements of biomaterial-based nerve guidance conduits have now been well established and include being able to bridge a nerve injury to support macroscopic guidance between nerve stumps, while being strong enough to withstand longitudinal tension and circumferential compression, in addition to being mechanically sound to facilitate

Common peroneal neuropathy related to cryotherapy and compression in a footballer.

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Babwah, Terence

2011-01-01

This report describes the effect of excessive cooling with ice, and compression with a plastic wrap on the common peroneal nerve (CPN) for 90 minutes in a professional footballer, which led to a common peroneal nerve palsy and a resulting footdrop. It highlights the need to be cautious with regards to the duration and frequency of icing as well as the choice of anchoring material when applying ice to injured areas that have superficial nerves passing nearby. Full recovery of the CPN function occurred in this athlete after five weeks. The major causes of footdrop and common causes of common peroneal neuropathy are discussed.

[Accident-induced lesions of the facial nerve in relation to the extent of pyramidal pneumatization].

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Kadoori, S; Limberg, C

1985-12-01

Perilabyrinthine pneumatisation of the petrous pyramid constitutes a risk factor for the facial nerve in its labyrinthine part in a fracture of the temporal bone because serious splintering of bone is possible. Splinters dislocated into the Fallopian canal may damage the nerve seriously. On the other hand a perineural haematoma can flow out of the canal into the neighbouring cells through dehiscences or through the fractured canal walls and a compression of the nerve may be avoided. The decision to undertake early surgical intervention must take into account the degree of pneumatisation of the pyramid in posttraumatic lesions of the facial nerve. The timing and extent of recovery cannot be predicted.

Function and morphology correlates of rectal nerve mechanoreceptors innervating the guinea pig internal anal sphincter.

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Lynn, P A; Brookes, S J H

2011-01-01

Mechanoreceptors to the internal anal sphincter (IAS) contribute to continence and normal defecation, yet relatively little is known about their function or morphology. We investigated the function and structure of mechanoreceptors to the guinea pig IAS. Extracellular recordings from rectal nerve branches to the IAS in vitro, combined with anterograde labeling of recorded nerve trunks, were used to characterize extrinsic afferent nerve endings activated by circumferential distension. Slowly adapting, stretch-sensitive afferents were recorded in rectal nerves to the IAS. Ten of 11 were silent under basal conditions and responded to circumferential stretch in a saturating linear manner. Rectal nerve afferents responded to compression with von Frey hairs with low thresholds (0.3-0.5 mN) and 3.4 ± 0.5 discrete, elongated mechanosensitive fields of innervation aligned parallel to circular muscle bundles (length = 62 ± 16 mm, n = 10). Anterogradely labeled rectal nerve axons typically passed through sparse irregular myenteric ganglia adjacent to the IAS, before ending in extensive varicose arrays within the circular muscle and, to a lesser extent, the longitudinal muscle overlying the IAS. Few (8%) IAS myenteric ganglia contained intraganglionic laminar endings. In eight preparations, mechanotransduction sites were mapped in combination with successful anterograde fills. Mechanotransduction sites were strongly associated with extensive fine varicose arrays within the circular muscle (P IAS are likely to correspond to extensive fine varicose arrays within the circular muscle. © 2010 Blackwell Publishing Ltd.

Persistent alterations in active and passive electrical membrane properties of regenerated nerve fibers of man and mice

DEFF Research Database (Denmark)

Moldovan, Mihai; Alvarez Herrero, Susana; Rosberg, Mette R.

2016-01-01

Excitability of regenerated fibers remains impaired due to changes in both passive cable properties and alterations in the voltage-dependent membrane function. These abnormalities were studied by mathematical modeling in human regenerated nerves and experimental studies in mice. In three adult male...... activity protocol triggered partial Wallerian degeneration in regenerated nerves but not in control nerves from age-matched mice. The current data suggest that the nodal voltage-gated ion channel machinery is restored in regenerated axons, although the electrical separation from the internodal compartment...... remains compromised. Due to the persistent increase in number of nodes, the increased activity-dependent Na+ influx could lead to hyperactivity of the Na+/K+ pump resulting in membrane hyperpolarization and neurotoxic energy insufficiency during strenuous activity....

Intramuscular Lipoma-Induced Occipital Neuralgia on the Lesser Occipital Nerve.

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Han, Hyun Ho; Kim, Hak Soo; Rhie, Jong Won; Moon, Suk Ho

2016-06-01

Occipital neuralgia (ON) is commonly characterized by a neuralgiform headache accompanied by a paroxysmal burning sensation in the dermatome area of the greater, lesser, or third occipital nerve. The authors report a rare case of ON caused by an intramuscular lipoma originating from the lesser occipital nerve.A 52-year-old man presented with sharp pain in the left postauricular area with a 3 × 2-cm palpable mass. Computed tomography revealed a mass suspiciously resembling an intramuscular lipoma within splenius muscle. In the operation field, a protruding mass causing stretching of the lesser occipital nerve was found. After complete resection, the neuralgiform headache symptom had resolved and the intramuscular lipoma was confirmed through histopathology.Previous studies on the causes of ON have reported that variation in normal anatomic structures results in nerve compression. Occipital neuralgia, however, caused by intramuscular lipomas in splenius muscles have not been previously reported, and the dramatic resolution following surgery makes it an interesting case worth reporting.

Active patient decision making regarding nerve sparing during radical prostatectomy: a novel approach.

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Lavery, Hugh J; Prall, David N; Abaza, Ronney

2011-08-01

The motivation to preserve sexual function can vary widely among patients before prostatectomy. Increasing patient involvement may allow a more personalized experience and may improve satisfaction. We assessed a strategy of surgeon deference to patient choice in regard to nerve sparing to determine to what degree patients are rational actors and capable of active decision making. A total of 150 patients treated with prostatectomy participated in a standardized preoperative discussion regarding the concept of nerve sparing, extracapsular extension and the potential need for adjuvant radiation in the event of local recurrence. Each patient was given his nomogram predicted risk of extracapsular extension and then elected nerve sparing or nonnerve sparing. The corresponding procedure was performed unless grossly invasive disease was encountered. Of the 150 patients 109 chose nerve sparing (73%) and 41 chose nonnerve sparing (27%). In patients with a nomogram predicted risk of extracapsular extension less than 20%, 20% to 50% and greater than 50%, nerve sparing was elected by 88%, 41% and 25%, respectively. Patients with lower risks of extracapsular extension electing nonnerve sparing were older and had higher rates of erectile dysfunction. Empowering patients to decide on their nerve sparing status is a reasonable strategy that did not lead to a high rate of patients with a high risk of extracapsular extension electing nerve sparing. With proper counseling informed patients made reasonable decisions, and appeared to be conservative, prioritizing cancer control in the majority of instances where extracapsular extension risk was high. In addition, they may have been overly conservative in electing nonnerve sparing when the risk was low. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Phrenic and hypoglossal nerve activity during respiratory response to hypoxia in 6-OHDA unilateral model of Parkinson's disease.

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Andrzejewski, Kryspin; Budzińska, Krystyna; Kaczyńska, Katarzyna

2017-07-01

Parkinson's disease (PD) patients apart from motor dysfunctions exhibit respiratory disturbances. Their mechanism is still unknown and requires investigation. Our research was designed to examine the activity of phrenic (PHR) and hypoglossal (HG) nerves activity during a hypoxic respiratory response in the 6-hydroxydopamine (6-OHDA) model of PD. Male adult Wistar rats were injected unilaterally with 6-OHDA (20μg) or the vehicle into the right medial forebrain bundle (MFB). Two weeks after the surgery the activity of the phrenic and hypoglossal nerve was registered in anesthetized, vagotomized, paralyzed, and mechanically ventilated rats under normoxic and hypoxic conditions. Lesion effectiveness was confirmed by the cylinder test, performed before the MFB injection and 14days after, before the respiratory experiment. 6-OHDA lesioned animals showed a significant increase in normoxic inspiratory time. Expiratory time and total time of the respiratory cycle were prolonged in PD rats after hypoxia. The amplitude of the PHR activity and its minute activity were increased in comparison to the sham group at recovery time and during 30s of hypoxia. The amplitude of the HG activity was increased in response to hypoxia in 6-OHDA lesioned animals. The degeneration of dopaminergic neurons decreased the pre-inspiratory/inspiratory ratio of the hypoglossal burst amplitude during and after hypoxia. Unilateral MFB lesion changed the activity of the phrenic and hypoglossal nerves. The altered pre-inspiratory hypoglossal nerve activity indicates modifications to the central mechanisms controlling the activity of the HG nerve and may explain respiratory disorders seen in PD, i.e. apnea. Copyright © 2017 Elsevier Inc. All rights reserved.

MR imaging and T2 measurements in peripheral nerve repair with activation of Toll-like receptor 4 of neurotmesis

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Zhang, Xiang; Zhang, Fang; Lu, Liejing; Li, Haojiang; Wen, Xuehua; Shen, Jun [Sun Yat-Sen University, Department of Radiology, Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong (China)

2014-05-15

To investigate the role of MR imaging in neurotmesis combined with surgical repair and Toll-like receptor 4 (TLR4) activation. Forty-eight rats received subepineurial microinjection of the TLR4 agonist lipopolysaccharide (LPS, n = 24) or phosphate buffered saline (PBS, n = 24) immediately after surgical repair of the transected sciatic nerve. Sequential fat-suppressed T2-weighted imaging and quantitative T2 measurements were obtained at 3, 7, 14 and 21 days after surgery, with histologic assessments performed at regular intervals. T2 relaxation times and histological quantification of the distal stumps were measured and compared. The distal stumps of transected nerves treated with LPS or PBS both showed persistent enlargement and hyperintense signal. T2 values of the distal stumps showed a rapid rise to peak level followed by a rapid decline pattern in nerves treated with LPS, while exhibiting a slow rise to peak value followed by a slow decline in nerves treated with PBS. Nerves treated with LPS exhibited more prominent macrophage recruitment, faster myelin debris clearance and more pronounced nerve regeneration. Nerves treated with TLR4 activation had a characteristic pattern of T2 value change over time. Longitudinal T2 measurements can be used to detect the enhanced repair effect associated with TLR4 activation in the surgical repair of neurotmesis. (orig.)

Salmon and human thrombin differentially regulate radicular pain, glial-induced inflammation and spinal neuronal excitability through protease-activated receptor-1.

Directory of Open Access Journals (Sweden)

Jenell R Smith

Full Text Available Chronic neck pain is a major problem with common causes including disc herniation and spondylosis that compress the spinal nerve roots. Cervical nerve root compression in the rat produces sustained behavioral hypersensitivity, due in part to the early upregulation of pro-inflammatory cytokines, the sustained hyperexcitability of neurons in the spinal cord and degeneration in the injured nerve root. Through its activation of the protease-activated receptor-1 (PAR1, mammalian thrombin can enhance pain and inflammation; yet at lower concentrations it is also capable of transiently attenuating pain which suggests that PAR1 activation rate may affect pain maintenance. Interestingly, salmon-derived fibrin, which contains salmon thrombin, attenuates nerve root-induced pain and inflammation, but the mechanisms of action leading to its analgesia are unknown. This study evaluates the effects of salmon thrombin on nerve root-mediated pain, axonal degeneration in the root, spinal neuronal hyperexcitability and inflammation compared to its human counterpart in the context of their enzymatic capabilities towards coagulation substrates and PAR1. Salmon thrombin significantly reduces behavioral sensitivity, preserves neuronal myelination, reduces macrophage infiltration in the injured nerve root and significantly decreases spinal neuronal hyperexcitability after painful root compression in the rat; whereas human thrombin has no effect. Unlike salmon thrombin, human thrombin upregulates the transcription of IL-1β and TNF-α and the secretion of IL-6 by cortical cultures. Salmon and human thrombins cleave human fibrinogen-derived peptides and form clots with fibrinogen with similar enzymatic activities, but salmon thrombin retains a higher enzymatic activity towards coagulation substrates in the presence of antithrombin III and hirudin compared to human thrombin. Conversely, salmon thrombin activates a PAR1-derived peptide more weakly than human thrombin. These

Ultrasound of the elbow with emphasis on detailed assessment of ligaments, tendons, and nerves

International Nuclear Information System (INIS)

De Maeseneer, Michel; Brigido, Monica Kalume; Antic, Marijana; Lenchik, Leon; Milants, Annemieke; Vereecke, Evie; Jager, Tjeerd; Shahabpour, Maryam

2015-01-01

Highlights: •Medial and lateral tendons: the different muscles forming these tendons can be followed up to the insertion. The imaging anatomy is reviewed. •Medial and lateral ligaments: the anatomy is complex and specialized imaging planes and arm positions are necessary for accurate assessment. •Biceps tendon: the anatomy of the distal biceps and lacertus fibrosus are discussed and illustrated with cadaveric correlation. •US imaging of the nerves about the elbow and visualization of the possible compression points is discussed. -- Abstract: The high resolution and dynamic capability of ultrasound make it an excellent tool for assessment of superficial structures. The ligaments, tendons, and nerves about the elbow can be fully evaluated with ultrasound. The medial collateral ligament consists of an anterior and posterior band that can easily be identified. The lateral ligament complex consists of the radial collateral ligament, ulnar insertion of the annular ligament, and lateral ulnar collateral ligament, easily identified with specialized probe positioning. The lateral ulnar collateral ligament can best be seen in the cobra position. On ultrasound medial elbow tendons can be followed nearly up to their common insertion. The pronator teres, flexor carpi radialis, palmaris longus, and flexor digitorum superficialis can be identified. The laterally located brachioradialis and extensor carpi radialis longus insert on the supracondylar ridge. The other lateral tendons can be followed up to their common insertion on the lateral epicondyle. The extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi, and extensor carpi ulnaris can be differentiated. The distal biceps tendon is commonly bifid. For a complete assessment of the distal biceps tendon specialized views are necessary. These include an anterior axial approach, medial and lateral approach, and cobra position. In the cubital tunnel the ulnar nerve is covered by the ligament of Osborne

Ultrasound of the elbow with emphasis on detailed assessment of ligaments, tendons, and nerves

Energy Technology Data Exchange (ETDEWEB)

De Maeseneer, Michel, E-mail: Michel.demaeseneer@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Brigido, Monica Kalume, E-mail: Mbrigido@med.umich.edu [Department of Radiology, University of Michigan, Ann Arbor, MI (United States); Antic, Marijana, E-mail: Misscroa@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Lenchik, Leon, E-mail: Llenchik@wakehealth.edu [Department of Radiology, Wake Forest University, Winston-Salem, NC (United States); Milants, Annemieke, E-mail: Annemieke.Milants@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Vereecke, Evie, E-mail: Evie.Vereecke@kuleuven-kulak.be [Department of Anatomy, KULAK, Katholieke Universiteit Leuven, Campus Kortrijk, Kortrijk (Belgium); Jager, Tjeerd [Aalsters Stedelijk Ziekenhuis, Aalst (Belgium); Shahabpour, Maryam, E-mail: Maryam.Shahabpour@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium)

2015-04-15

Highlights: •Medial and lateral tendons: the different muscles forming these tendons can be followed up to the insertion. The imaging anatomy is reviewed. •Medial and lateral ligaments: the anatomy is complex and specialized imaging planes and arm positions are necessary for accurate assessment. •Biceps tendon: the anatomy of the distal biceps and lacertus fibrosus are discussed and illustrated with cadaveric correlation. •US imaging of the nerves about the elbow and visualization of the possible compression points is discussed. -- Abstract: The high resolution and dynamic capability of ultrasound make it an excellent tool for assessment of superficial structures. The ligaments, tendons, and nerves about the elbow can be fully evaluated with ultrasound. The medial collateral ligament consists of an anterior and posterior band that can easily be identified. The lateral ligament complex consists of the radial collateral ligament, ulnar insertion of the annular ligament, and lateral ulnar collateral ligament, easily identified with specialized probe positioning. The lateral ulnar collateral ligament can best be seen in the cobra position. On ultrasound medial elbow tendons can be followed nearly up to their common insertion. The pronator teres, flexor carpi radialis, palmaris longus, and flexor digitorum superficialis can be identified. The laterally located brachioradialis and extensor carpi radialis longus insert on the supracondylar ridge. The other lateral tendons can be followed up to their common insertion on the lateral epicondyle. The extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi, and extensor carpi ulnaris can be differentiated. The distal biceps tendon is commonly bifid. For a complete assessment of the distal biceps tendon specialized views are necessary. These include an anterior axial approach, medial and lateral approach, and cobra position. In the cubital tunnel the ulnar nerve is covered by the ligament of Osborne

After microvascular decompression to treat trigeminal neuralgia, both immediate pain relief and recurrence rates are higher in patients with arterial compression than with venous compression.

Science.gov (United States)

Shi, Lei; Gu, Xiaoyan; Sun, Guan; Guo, Jun; Lin, Xin; Zhang, Shuguang; Qian, Chunfa

2017-07-04

We explored differences in postoperative pain relief achieved through decompression of the trigeminal nerve compressed by arteries and veins. Clinical characteristics, intraoperative findings, and postoperative curative effects were analyzed in 72 patients with trigeminal neuralgia who were treated by microvascular decompression. The patients were divided into arterial and venous compression groups based on intraoperative findings. Surgical curative effects included immediate relief, delayed relief, obvious reduction, and invalid result. Among the 40 patients in the arterial compression group, 32 had immediate pain relief of pain (80.0%), 5 cases had delayed relief (12.5%), and 3 cases had an obvious reduction (7.5%). In the venous compression group, 12 patients had immediate relief of pain (37.5%), 13 cases had delayed relief (40.6%), and 7 cases had an obvious reduction (21.9%). During 2-year follow-up period, 6 patients in the arterial compression group experienced recurrence of trigeminal neuralgia, but there were no recurrences in the venous compression group. Simple artery compression was followed by early relief of trigeminal neuralgia more often than simple venous compression. However, the trigeminal neuralgia recurrence rate was higher in the artery compression group than in the venous compression group.

Posterior interosseous nerve palsy as a complication of friction massage in tennis elbow.

Science.gov (United States)

Wu, Ya-Ying; Hsu, Wei-Chih; Wang, Han-Cheng

2010-08-01

Friction massage is a commonly used physical therapy that is usually safe and without complication. We report an unusual case of posterior interosseous nerve palsy that arose after friction massage. Electrophysiologic findings confirmed a focal neuropathy 4-6 cm distal to the lateral epicondyle. The neurologic symptoms resolved completely 2 mos after discontinuation of friction massage. This case experience broadens the spectrum of etiologies of posterior interosseous nerve palsy. Nerve conduction studies may be a useful adjunct to a thorough physical examination to confirm the diagnosis and is important to prognostic evaluation, if unexplained neurologic symptoms develop after certain physical therapy procedures. Further treatment includes avoiding compression and observation.

Compressive strength of dental composites photo-activated with different light tips

International Nuclear Information System (INIS)

Galvão, M R; Campos, E A; Rastelli, A N S; Andrade, M F; Caldas, S G F R; Calabrez-Filho, S; Bagnato, V S

2013-01-01

The aim of this study was to evaluate the compressive strength of microhybrid (Filtek™ Z250) and nanofilled (Filtek™ Supreme XT) composite resins photo-activated with two different light guide tips, fiber optic and polymer, coupled with one LED. The power density was 653 mW cm −2 when using the fiber optic light tip and 596 mW cm −2 with the polymer. After storage in distilled water at 37 ± 2 °C for seven days, the samples were subjected to mechanical testing of compressive strength in an EMIC universal mechanical testing machine with a load cell of 5 kN and speed of 0.5 mm min −1 . The statistical analysis was performed using ANOVA with a confidence interval of 95% and Tamhane’s test. The results showed that the mean values of compressive strength were not influenced by the different light tips (p > 0.05). However, a statistical difference was observed (p < 0.001) between the microhybrid composite resin photo-activated with the fiber optic light tip and the nanofilled composite resin. Based on these results, it can be concluded that microhybrid composite resin photo-activated with the fiber optic light tip showed better results than nanofilled, regardless of the tip used, and the type of the light tip did not influence the compressive strength of either composite. Thus, the presented results suggest that both the fiber optic and polymer light guide tips provide adequate compressive strength to be used to make restorations. However, the fiber optic light tip associated with microhybrid composite resin may be an interesting option for restorations mainly in posterior teeth. (paper)

Usefulness of ultrasound assessment of median nerve mobility in carpal tunnel syndrome.

Science.gov (United States)

Park, Gi-Young; Kwon, Dong Rak; Seok, Jung Im; Park, Dong-Soon; Cho, Hee Kyung

2018-01-01

Background Carpal tunnel syndrome (CTS) is the most common peripheral compression neuropathy of the upper extremity. Recently, dynamic ultrasound (US) imaging has shown differences in median nerve mobility between the affected and unaffected sides in CTS. Purpose The present study was performed to compare the median nerve mobility between patients with CTS and healthy individuals, and to correlate median nerve mobility with the severity of CTS. Material and Methods A total of 101 patients (128 wrists) with CTS and 43 healthy individuals (70 wrists) were evaluated. Electrodiagnostic studies were initially conducted to determine the neurophysiological grading scale (NGS). The cross-sectional area (CSA) of the median nerve and the grade of median nerve mobility were measured using US. Results The mean grade of median nerve mobility in the CTS group (1.9) was significantly lower than that in the control group (2.6; P mobility and distal motor latency of the median nerve (r = -0.218, P = 0.015), NGS (r = -0.207, P = 0.020) and CSA of the median nerve (r = -0.196, P = 0.028). Conclusion The grade of median nerve mobility was negatively correlated with the severity of CTS. US assessment of median nerve mobility may be useful in diagnosing and determining the severity of CTS.

Tonic aortic depressor nerve stimulation does not impede baroreflex dynamic characteristics concomitantly mediated by the stimulated nerve.

Science.gov (United States)

Kawada, Toru; Turner, Michael J; Shimizu, Shuji; Kamiya, Atsunori; Shishido, Toshiaki; Sugimachi, Masaru

2018-03-01

Although electrical activation of the carotid sinus baroreflex (baroreflex activation therapy) is being explored as a device therapy for resistant hypertension, possible effects on baroreflex dynamic characteristics of interaction between electrical stimulation and pressure inputs are not fully elucidated. To examine whether the electrical stimulation of the baroreceptor afferent nerve impedes normal short-term arterial pressure (AP) regulation mediated by the stimulated nerve, we electrically stimulated the right aortic depressor nerve (ADN) while estimating the baroreflex dynamic characteristics by imposing pressure inputs to the isolated baroreceptor region of the right ADN in nine anesthetized rats. A Gaussian white noise signal with a mean of 120 mmHg and standard deviation of 20 mmHg was used for the pressure perturbation. A tonic ADN stimulation (2 or 5 Hz, 10 V, 0.1-ms pulse width) decreased mean sympathetic nerve activity (367.0 ± 70.9 vs. 247.3 ± 47.2 arbitrary units, P ADN stimulation did not affect the slope of dynamic gain in the neural arc transfer function from pressure perturbation to sympathetic nerve activity (16.9 ± 1.0 vs. 14.7 ± 1.6 dB/decade, not significant). These results indicate that electrical stimulation of the baroreceptor afferent nerve does not significantly impede the dynamic characteristics of the arterial baroreflex concomitantly mediated by the stimulated nerve. Short-term AP regulation by the arterial baroreflex may be preserved during the baroreflex activation therapy.

Clinical potential and limitation of MRI for degenerative lumbar spinal diseases. Comparison of MRI, myelography, CT and selective nerve root infiltration

Energy Technology Data Exchange (ETDEWEB)

Seki, Michihiro; Kikuchi, Shinichi [Fukushima Medical Coll. (Japan)

1994-12-01

To assess the clinical potential and limitations of magnetic resonance imaging (MRI) in degenerative lumbar spinal diseases, the findings of MR imaging were compared with those of myelography and CT. The subjects were 80 patients with intervertebral disc herniation (46), spondylosis (28), degenerative spondylolisthesis (5), and spondylolysis (one). There was a good correlation between sagittal MRI (T1-weighted images) and myelography in measuring the anteroposterior diameter and the compression rate of the injured dural canal in all disease categories. However, MRI was inferior, irrespective of sagittal and coronal images, to myelography in detecting blocking of the dural canal and intradural findings such as redundant nerve roots. MRI was inferior to selective nerve root infiltration in visualizing the compression of the nerve root, irrespective of diseases; however, there was no difference in abnormal findings of the running of nerve root between the two modalities. Transverse MRI was superior to CT in visualizing the nerve root. Thus, MRI alone is insufficient for the diagnosis of degenerative lumbar spinal diseases, and the other modalities should be supplementary for pathophysiological understanding of these diseases. (N.K.).

Clinical potential and limitation of MRI for degenerative lumbar spinal diseases. Comparison of MRI, myelography, CT and selective nerve root infiltration

International Nuclear Information System (INIS)

Seki, Michihiro; Kikuchi, Shinichi

1994-01-01

To assess the clinical potential and limitations of magnetic resonance imaging (MRI) in degenerative lumbar spinal diseases, the findings of MR imaging were compared with those of myelography and CT. The subjects were 80 patients with intervertebral disc herniation (46), spondylosis (28), degenerative spondylolisthesis (5), and spondylolysis (one). There was a good correlation between sagittal MRI (T1-weighted images) and myelography in measuring the anteroposterior diameter and the compression rate of the injured dural canal in all disease categories. However, MRI was inferior, irrespective of sagittal and coronal images, to myelography in detecting blocking of the dural canal and intradural findings such as redundant nerve roots. MRI was inferior to selective nerve root infiltration in visualizing the compression of the nerve root, irrespective of diseases; however, there was no difference in abnormal findings of the running of nerve root between the two modalities. Transverse MRI was superior to CT in visualizing the nerve root. Thus, MRI alone is insufficient for the diagnosis of degenerative lumbar spinal diseases, and the other modalities should be supplementary for pathophysiological understanding of these diseases. (N.K.)

Low Median Nerve Palsy as Initial Manifestation of Churg-Strauss Syndrome.

Science.gov (United States)

Roh, Young Hak; Koh, Young Do; Noh, Jung Ho; Gong, Hyun Sik; Baek, Goo Hyun

2017-06-01

Anterior interosseous nerve (AIN) syndrome is typically characterized by forearm pain and partial or complete dysfunction of the AIN-innervated muscles. Although the exact etiology and pathophysiology of the disorder remain unclear, AIN syndrome is increasingly thought to be an inflammatory condition of the nerve rather than a compressive neuropathy because the symptoms often resolve spontaneously following prolonged observation. However, peripheral neuropathy can be 1 of the first symptoms of systemic vasculitis that needs early systemic immunotherapy to prevent extensive nerve damage. Churg-Strauss syndrome (CSS; eosinophilic granulomatosis with polyangiitis) is 1 type of primary systemic vasculitis that frequently damages the peripheral nervous system. CSS-associated neuropathy usually involves nerves of the lower limb, and few studies have reported on the involvement of the upper limb alone. We report on a rare case of low median nerve palsy as the initial manifestation of CSS. The patient recovered well with early steroid treatment for primary systemic vasculitis. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Lumbar Nerve Root Occupancy in the Foramen in Achondroplasia

Science.gov (United States)

Modi, Hitesh N.; Song, Hae-Ryong; Yang, Jae Hyuk

2008-01-01

Lumbar stenosis is common in patients with achondroplasia because of narrowing of the neural canal. However, it is unclear what causes stenosis, narrowing of the central canal or foramina. We performed a morphometric analysis of the lumbar nerve roots and intervertebral foramen in 17 patients (170 nerve roots and foramina) with achondroplasia (eight symptomatic, nine asymptomatic) and compared the data with that from 20 (200 nerve roots and foramina) asymptomatic patients without achondroplasia presenting with low back pain without neurologic symptoms. The measurements were made on left and right parasagittal MRI scans of the lumbar spine. The foramen area and root area were reduced at all levels from L1 to L5 between the patients with achondroplasia (Groups I and II) and the nonachondroplasia group (Group III). The percentage of nerve root occupancy in the foramen between Group I and Group II as compared with the patients without achondroplasia was similar or lower. This implied the lumbar nerve root size in patients with achondroplasia was smaller than that of the normal population and thus there is no effective nerve root compression. Symptoms of lumbar stenosis in achondroplasia may be arising from the central canal secondary to degenerative disc disease rather than a true foraminal stenosis. Level of Evidence: Level I, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18259829

Facial reanimation by muscle-nerve neurotization after facial nerve sacrifice. Case report.

Science.gov (United States)

Taupin, A; Labbé, D; Babin, E; Fromager, G

2016-12-01

Recovering a certain degree of mimicry after sacrifice of the facial nerve is a clinically recognized finding. The authors report a case of hemifacial reanimation suggesting a phenomenon of neurotization from muscle-to-nerve. A woman benefited from a parotidectomy with sacrifice of the left facial nerve indicated for recurrent tumor in the gland. The distal branches of the facial nerve, isolated at the time of resection, were buried in the masseter muscle underneath. The patient recovered a voluntary hémifacial motricity. The electromyographic analysis of the motor activity of the zygomaticus major before and after block of the masseter nerve showed a dependence between mimic muscles and the masseter muscle. Several hypotheses have been advanced to explain the spontaneous reanimation of facial paralysis. The clinical case makes it possible to argue in favor of muscle-to-nerve neurotization from masseter muscle to distal branches of the facial nerve. It illustrates the quality of motricity that can be obtained thanks to this procedure. The authors describe a simple implantation technique of distal branches of the facial nerve in the masseter muscle during a radical parotidectomy with facial nerve sacrifice and recovery of resting tone but also a quality voluntary mimicry. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

A comparison between complete immobilisation and protected active mobilisation in sensory nerve recovery following isolated digital nerve injury.

LENUS (Irish Health Repository)

Henry, F P

2012-06-01

Post-operative immobilisation following isolated digital nerve repair remains a controversial issue amongst the microsurgical community. Protocols differ from unit to unit and even, as evidenced in our unit, may differ from consultant to consultant. We undertook a retrospective review of 46 patients who underwent isolated digital nerve repair over a 6-month period. Follow-up ranged from 6 to 18 months. Twenty-four were managed with protected active mobilisation over a 4-week period while 22 were immobilised over the same period. Outcomes such as return to work, cold intolerance, two-point discrimination and temperature differentiation were used as indicators of clinical recovery. Our results showed that there was no significant difference noted in either clinical assessment of recovery or return to work following either post-operative protocol, suggesting that either regime may be adopted, tailored to the patient\\'s needs and resources of the unit.

Changes in lumbosacral spinal nerve roots on diffusion tensor imaging in spinal stenosis

OpenAIRE

Zhong-jun Hou; Yong Huang; Zi-wen Fan; Xin-chun Li; Bing-yi Cao

2015-01-01

Lumbosacral degenerative disc disease is a common cause of lower back and leg pain. Conventional T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) scans are commonly used to image spinal cord degeneration. However, these modalities are unable to image the entire lumbosacral spinal nerve roots. Thus, in the present study, we assessed the potential of diffusion tensor imaging (DTI) for quantitative assessment of compressed lumbosacral spinal nerve roots. Subjects were 20 young healthy v...

The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

Energy Technology Data Exchange (ETDEWEB)

Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi [Jichi Medical School, Minamikawachi, Tochigi (Japan)

2001-07-01

In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

International Nuclear Information System (INIS)

Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi

2001-01-01

In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

Pneumatic antishock garment inflation activates the human sympathetic nervous system by abdominal compression.

Science.gov (United States)

Garvin, Nathan M; Levine, Benjamin D; Raven, Peter B; Pawelczyk, James A

2014-01-01

Pneumatic antishock garments (PASG) have been proposed to exert their blood pressure-raising effect mechanically, i.e. by increasing venous return and vascular resistance of the lower body. We tested whether, alternatively, PASG inflation activates the sympathetic nervous system. Five men and four women wore PASG while mean arterial pressure (MAP), muscle sympathetic nerve activity (MSNA), heart rate and stroke volume were measured. One leg bladder (LEG) and the abdominal bladder (ABD) of the trousers were inflated individually and in combination (ABD+LEG), at 60 or 90 mmHg for 3 min. By the end of 3 min of inflation, conditions that included the ABD region caused significant increases in MAP in a dose-dependent fashion (7 ± 2, 8 ± 3, 14 ± 4 and 13 ± 5 mmHg for ABD60, ABD+LEG60, ABD90 and ABD+LEG90, respectively, P < 0.05). Likewise, inflation that included ABD caused significant increases in total MSNA compared with control values [306 ± 70, 426 ± 98 and 247 ± 79 units for ABD60, ABD90 and ABD+LEG90, respectively, P < 0.05 (units = burst frequency × burst amplitude]. There were no changes in MAP or MSNA in the LEG-alone conditions. The ABD inflation also caused a significant decrease in stroke volume (-11 ± 3 and -10 ± 3 ml per beat in ABD90 and ABD+LEG90, respectively, P < 0.05) with no change in cardiac output. Neither cardiopulmonary receptor deactivation nor mechanical effects can account for a slowly developing rise in both sympathetic activity and blood pressure during ABD inflation. Rather, these data provide direct evidence that PASG inflation activates the sympathetic nervous system secondarily to abdominal, but not leg, compression.

Ulnar nerve entrapment in Guyon's canal due to a lipoma.

Science.gov (United States)

Ozdemir, O; Calisaneller, T; Gerilmez, A; Gulsen, S; Altinors, N

2010-09-01

Guyon's canal syndrome is an ulnar nerve entrapment at the wrist or palm that can cause motor, sensory or combined motor and sensory loss due to various factors . In this report, we presented a 66-year-old man admitted to our clinic with a history of intermittent pain in the left palm and numbness in 4th and 5th finger for two years. His neurological examination revealed a sensory impairment in the right fifth finger. Also, physical examination displayed a subcutaneous mobile soft tissue in ulnar side of the wrist. Electromyographic examination confirmed the diagnosis of type-1 Guyon's canal syndrome. Under axillary blockage, a lipoma compressing the ulnar nerve was excised totally and ulnar nerve was decompressed. The symptoms were improved after the surgery and patient was symptom free on 3rd postoperative week.

Right hypoglossal nerve paralysis after tracheal intubation for aesthetic breast surgery

Directory of Open Access Journals (Sweden)

Sammy Al-Benna

2013-01-01

Full Text Available Aesthetic and functional complications caused by general anesthesia have been rarely described after aesthetic surgery. We report a case of unilateral right hypoglossal nerve paralysis following the use of a cuffed endotracheal airway in a 24-year-old woman undergoing aesthetic breast surgery. Neurological examination and magnetic resonance imaging of the head failed to provide additional insights into the cause of the nerve injury. Postoperatively, the patient was carefully monitored and made a full recovery within 2 weeks without any pharmacological treatment. The transient hypoglossal nerve paralysis seemed to be due to neuropraxia. In this patient, we postulate that the right hypoglossal nerve was compressed between the endotracheal tube cuff and the hyoid bone, which was inflated with 30 cm H 2 O. Patients undergoing aesthetic surgery must be appropriately and adequately informed that postoperative aesthetic and functional deficits can occur due to anesthesia as well as the surgery.

Avaliação do trofismo muscular de sóleos de ratos wistar após compressão nervosa e tratamento com corrente de alta voltagem Evaluación del tropismo del músculo sóleo de ratas wistar después de la compresión del nervio y tratamiento con corriente de alto voltaje Assessment of wistar rats' soleus muscle trophism after nerve compression and treatment with high-voltage current

Directory of Open Access Journals (Sweden)

Gladson Ricardo Flor Bertolini

2012-12-01

Full Text Available OBJETIVO: avaliar a corrente de alta voltagem sobre o trofismo de sóleos de ratos com compressão de nervo isquiático. Dezoito ratos distribuídos em: GS - compressão nervosa e simulacro; GP+ - compressão e tratado com corrente anódica; GP- - compressão e catódica. Ao final, os sóleos foram dissecados e pesados em balança analítica. Em seguida foram montadas lâminas de cortes transversais, observadas em microscópio óptico de luz comum e digitalizadas, para análise do menor diâmetro de 100 fibras por músculo. RESULTADOS: todos os grupos apresentaram menor trofismo pelas duas formas de avaliação (p0,05. CONCLUSÃO: a corrente de alta voltagem não inibiu a hipotrofia em sóleos submetidos à compressão nervosa.OBJETIVO: Evaluar la corriente de alto voltaje en el tropismo del sóleo de ratas con la compresión del nervio ciático. Dieciocho ratas se dividieron en: GS - compresión del nervio y la falsa; GP+ - compresión y tratados con corriente anódica; GP- - compresión y el cátodo. Por último, fueron los sóleos disecados y pesados ​​en una balanza analítica. Luego diapositivas de secciones transversales fueron montadas para la observación al microscopio de luz común y digitalizadas para el análisis de menor diámetro de 100 fibras por músculo. RESULTADOS: Todos los grupos mostraron menor tropismo, las dos formas de evaluación (p 0,05. CONCLUSIÓN: La corriente de alto voltaje no inhibe la atrofia en el músculo sóleo se sometieron a la compresión del nervio.AIM: to evaluate the high voltage current on the tropism of rats soleus with sciatic nerve compression. Eighteen rats were divided into: GS - nerve compression and sham; GP + - compression and treated with anodic current; GP - compression and cathode. Finally, the soleus were dissected and weighed on an analytical balance. Then slides were mounted cross sections observed in light microscope and digitized for analysis of smaller diameter of 100 fibers per

Clinical and imaging characteristics of foraminal nerve root disorders of the lumbar spine

International Nuclear Information System (INIS)

Nishi, Tomio; Tani, Takayuki; Suzuki, Norio; Aonuma, Hiroshi

2009-01-01

We analyzed cases of lumbar nerve root compression at intervertebral foramina, by comparing 19 cases of foraminal stenosis (FS), and 38 cases of foraminal hernia (FH) with 21 cases of lumbar canal stenosis (LCS). Japan Orthopedic Association (JOA) scores, intervertebral disc degeneration, anatomical measurements of the nerve root foramina and the MRI findings were reviewed. The scores for pain in the lower extremities, and walking ability were both lowest in the FS group. The scores for low back pain, lower extremities, and sensory disturbances were lowest in the FH group. Anterior-posterior diameters of the nerve root foramina were smaller in the FS group and FH group than in the LCS group. More degenerated discs and short length of upper part of the nerve root foramina were seen in FS group than in the other groups. The MRI images of so-called black out nerve root foramina were positive in 63.6% of FS cases, 75% of FH cases. (author)

Terminal nerve: cranial nerve zero

Directory of Open Access Journals (Sweden)

Jorge Eduardo Duque Parra

2006-12-01

Full Text Available It has been stated, in different types of texts, that there are only twelve pairs of cranial nerves. Such texts exclude the existence of another cranial pair, the terminal nerve or even cranial zero. This paper considers the mentioned nerve like a cranial pair, specifying both its connections and its functional role in the migration of liberating neurons of the gonadotropic hormone (Gn RH. In this paper is also stated the hypothesis of the phylogenetic existence of a cerebral sector and a common nerve that integrates the terminal nerve with the olfactory nerves and the vomeronasals nerves which seem to carry out the odors detection function as well as in the food search, pheromone detection and nasal vascular regulation.

Treatment of peroneal nerve injuries with simultaneous tendon transfer and nerve exploration.

Science.gov (United States)

Ho, Bryant; Khan, Zubair; Switaj, Paul J; Ochenjele, George; Fuchs, Daniel; Dahl, William; Cederna, Paul; Kung, Theodore A; Kadakia, Anish R

2014-08-06

Common peroneal nerve palsy leading to foot drop is difficult to manage and has historically been treated with extended bracing with expectant waiting for return of nerve function. Peroneal nerve exploration has traditionally been avoided except in cases of known traumatic or iatrogenic injury, with tendon transfers being performed in a delayed fashion after exhausting conservative treatment. We present a new strategy for management of foot drop with nerve exploration and concomitant tendon transfer. We retrospectively reviewed a series of 12 patients with peroneal nerve palsies that were treated with tendon transfer from 2005 to 2011. Of these patients, seven were treated with simultaneous peroneal nerve exploration and repair at the time of tendon transfer. Patients with both nerve repair and tendon transfer had superior functional results with active dorsiflexion in all patients, compared to dorsiflexion in 40% of patients treated with tendon transfers alone. Additionally, 57% of patients treated with nerve repair and tendon transfer were able to achieve enough function to return to running, compared to 20% in patients with tendon transfer alone. No patient had full return of native motor function resulting in excessive dorsiflexion strength. The results of our limited case series for this rare condition indicate that simultaneous nerve repair and tendon transfer showed no detrimental results and may provide improved function over tendon transfer alone.

Tibial nerve somatosensory evoked potentials in dogs with degenerative lumbosacral stenosis.

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Meij, Björn P; Suwankong, Niyada; van den Brom, Walter E; Venker-van Haagen, Anjop J; Hazewinkel, Herman A W

2006-02-01

To determine somatosensory evoked potentials (SEPs) in dogs with degenerative lumbosacral stenosis (DLS) and in healthy dogs. Clinical and experimental study. Dogs with DLS (n = 21) and 11 clinically normal dogs, age, and weight matched. Under anesthesia, the tibial nerve was stimulated at the caudolateral aspect of the stifle, and lumbar SEP (LSEP) were recorded percutaneously from S1 to T13 at each interspinous space. Cortical SEP (CSEP) were recorded from the scalp. LSEP were identified as the N1-P1 (latency 3-6 ms) and N2-P2 (latency 7-13 ms) wave complexes in the recordings of dogs with DLS and control dogs. Latency of N1-P1 increased and that of N2-P2 decreased as the active recording electrode was moved cranially from S1 to T13. Compared with controls, latencies were significantly delayed in DLS dogs: .8 ms for N1-P1 and 1.7 ms for the N2-P2 complex. CSEP were not different between groups. Surface needle recording of tibial nerve SEP can be used to monitor somatosensory nerve function of pelvic limbs in dogs. In dogs with DLS, the latency of LSEP, but not of CSEP, is prolonged compared with normal dogs. In dogs with lumbosacral pain from DLS, the cauda equina compression is sufficient to affect LSEP at the lumbar level.

Influence of local noxious heat stimulation on sensory nerve activity in the feline dental pulp.

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Ahlberg, K F

1978-05-01

The present investigation was undertaken to develop an experimental model in which noxious heat stimulation was used to produce increased intradental sensory nerve activity in canine teeth of anesthetized cats. Two techniques were evaluated in which both the method of recording and the nature of the stimulus varied. Slow heating (approx 1 degree C/s) to 47 degree C of the tooth surface (combined with recording from electrodes in open dentinal cavities) did not produce any persistent nerve activity. Repeated periods of brief intense heating (approx 60 degrees C/s) (combined with recording from amalgam electrodes placed on cavity floors) resulted in an immediate response and an afterdischarge (phase 3) generally persisting for 20--60 min. Maximum phase 3 activity was characteristic for the individual cat and ranged from 0.2 to 50.2 imp/s. mean value 10.6 imp/s (S.D. +/- 9.2). A systematically higher phase 3 activity was recorded in lower compared to upper canine teeth (p less than 0.05). The maximum phase 3 response generally occurred after 3-8 stimulations; the median number of required stimuli was 3. Repeated brief heat stimulations combined with the closed cavity recording technique may be used as an experimental model by which the mechanisms behind increases in intradental sensory nerve activity associated with tissue damage can be studied.

MR imaging of the lumber spine; Visualization capability of the nerve root

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Ishibashi, Kazumasa; Hieda, Hiroshi; Goto, Takeshi; Goto, Hiroshi; Koga, Hiromichi; Hiraoka, Kouji (Moji Rousai Hospital, Fukuoka (Japan))

1991-01-01

We studied visualization capability of the nerve root in mainly coronary section pattern using magnetic resonance imaging (MRI). MRI was carried out in 91 patients with lumbago and sciatica. Coronary section was additionally photographed in 58 cases of these patients (32 with intervertebral hernia, 20 with spinal canal stenosis, 2 with spondylolytic spondylolisthesis, 2 with compression fracture and the other 2 patients). The visualization capability of the nerve root was studied with photographing 2 pulse systems of the coronary section by using spin echo and field echo methods. The high signal area of the cerebrospinal fluid and nerve root in the normal lumbar vertebra was noted by field echo method, and pattern that is visualized by myelogram was obtained. The coincidence of the main foci (disturbed lesions of the nerve root) in the intervertebral hernia and coronary section pattern was noted in 21 of 32 cases (64.5%) with considerably high ratio. The condition of the nerve root in the blocked lesion was visualized in the spinal canal stenosis. (author).

Microsurgical Decompression of the Cochlear Nerve to Treat Disabling Tinnitus via an Endoscope-Assisted Retrosigmoid Approach: The Padua Experience.

Science.gov (United States)

Di Stadio, Arianna; Colangeli, Roberta; Dipietro, Laura; Martini, Alessandro; Parrino, Daniela; Nardello, Ennio; D'Avella, Domenico; Zanoletti, Elisabetta

2018-05-01

The use of surgical cochlear nerve decompression is controversial. This study aimed at investigating the safety and validity of microsurgical decompression via an endoscope-assisted retrosigmoid approach to treat tinnitus in patients with neurovascular compression of the cochlear nerve. Three patients with disabling tinnitus resulting from a loop in the internal auditory canal were evaluated with magnetic resonance imaging and tests of pure tone auditory, tinnitus, and auditory brain response (ABR) to identify the features of the cochlear nerve involvement. We observed a loop with a caliber greater than 0.8 mm in all patients. Patients were treated via an endoscope-assisted retrosigmoid microsurgical decompression. After surgery, none of the patients reported short-term or long-term complications. After surgery, tinnitus resolved immediately in 2 patients, whereas in the other patient symptoms persisted although they improved; in all patients, hearing was preserved and ABR improved. Microsurgical decompression via endoscope-assisted retrosigmoid approach is a promising, safe, and valid procedure for treating tinnitus caused by cochlear nerve compression. This procedure should be considered in patients with disabling tinnitus who have altered ABR and a loop that has a caliber greater than 0.8 mm and is in contact with the cochlear nerve. Copyright © 2018 Elsevier Inc. All rights reserved.

Neurophysiologic intraoperative monitoring of the vestibulocochlear nerve.

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Simon, Mirela V

2011-12-01

Neurosurgical procedures involving the skull base and structures within can pose a significant risk of damage to the brain stem and cranial nerves. This can have life-threatening consequences and/or result in devastating neurologic deficits. Over the past decade, intraoperative neurophysiology has significantly evolved and currently offers a great tool for live monitoring of the integrity of nervous structures. Thus, dysfunction can be identified early and prompt modification of the surgical management or operating conditions, leads to avoidance of permanent structural damage.Along these lines, the vestibulocochlear nerve (CN VIII) and, to a greater extent, the auditory pathways as they pass through the brain stem are especially at risk during cerebelopontine angle (CPA), posterior/middle fossa, or brain stem surgery. CN VIII can be damaged by several mechanisms, from vascular compromise to mechanical injury by stretch, compression, dissection, and heat injury. Additionally, cochlea itself can be significantly damaged during temporal bone drilling, by noise, mechanical destruction, or infarction, and because of rupture, occlusion, or vasospasm of the internal auditory artery.CN VIII monitoring can be successfully achieved by live recording of the function of one of its parts, the cochlear or auditory nerve (AN), using the brain stem auditory evoked potentials (BAEPs), electrocochleography (ECochG), and compound nerve action potentials (CNAPs) of the cochlear nerve.This is a review of these techniques, their principle, applications, methodology, interpretation of the evoked responses, and their change from baseline, within the context of surgical and anesthesia environments, and finally the appropriate management of these changes.

Selective detrusor activation by electrical sacral nerve root stimulation in spinal cord injury

NARCIS (Netherlands)

Rijkhoff, N. J.; Wijkstra, H.; van Kerrebroeck, P. E.; Debruyne, F. M.

1997-01-01

Electrical sacral nerve root stimulation can be used in spinal cord injury patients to induce urinary bladder contraction. However, existing stimulation methods activate simultaneously both the detrusor muscle and the urethral sphincter. Urine evacuation is therefore only possible using poststimulus

Vagus nerve stimulation inhibits activation of coagulation and fibrinolysis during endotoxemia in rats

NARCIS (Netherlands)

van Westerloo, D. J.; Giebelen, I. A. J.; Meijers, J. C. M.; Daalhuisen, J.; de Vos, A. F.; Levi, M. [=Marcel M.; van der Poll, T.

2006-01-01

BACKGROUND: Sepsis and endotoxemia are associated with concurrent activation of inflammation and the hemostatic mechanism, which both contribute to organ dysfunction and death. Electrical vagus nerve stimulation (VNS) has been found to inhibit tumor necrosis factor (TNF)-alpha release during

Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

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Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2014-10-01

Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity.

Reaction kinetics, reaction products and compressive strength of ternary activators activated slag designed by Taguchi method

NARCIS (Netherlands)

Yuan, B.; Yu, Q.L.; Brouwers, H.J.H.

2015-01-01

This study investigates the reaction kinetics, the reaction products and the compressive strength of slag activated by ternary activators, namely waterglass, sodium hydroxide and sodium carbonate. Nine mixtures are designed by the Taguchi method considering the factors of sodium carbonate content

G-CSF prevents caspase 3 activation in Schwann cells after sciatic nerve transection, but does not improve nerve regeneration.

Science.gov (United States)

Frost, Hanna K; Kodama, Akira; Ekström, Per; Dahlin, Lars B

2016-10-15

Exogenous granulocyte-colony stimulating factor (G-CSF) has emerged as a drug candidate for improving the outcome after peripheral nerve injuries. We raised the question if exogenous G-CSF can improve nerve regeneration following a clinically relevant model - nerve transection and repair - in healthy and diabetic rats. In short-term experiments, distance of axonal regeneration and extent of injury-induced Schwann cell death was quantified by staining for neurofilaments and cleaved caspase 3, respectively, seven days after repair. There was no difference in axonal outgrowth between G-CSF-treated and non-treated rats, regardless if healthy Wistar or diabetic Goto-Kakizaki (GK) rats were examined. However, G-CSF treatment caused a significant 13% decrease of cleaved caspase 3-positive Schwann cells at the lesion site in healthy rats, but only a trend in diabetic rats. In the distal nerve segments of healthy rats a similar trend was observed. In long-term experiments of healthy rats, regeneration outcome was evaluated at 90days after repair by presence of neurofilaments, wet weight of gastrocnemius muscle, and perception of touch (von Frey monofilament testing weekly). The presence of neurofilaments distal to the suture line was similar in G-CSF-treated and non-treated rats. The weight ratio of ipsi-over contralateral gastrocnemius muscles, and perception of touch at any time point, were likewise not affected by G-CSF treatment. In addition, the inflammatory response in short- and long-term experiments was studied by analyzing ED1 stainable macrophages in healthy rats, but in neither case was any attenuation seen at the injury site or distal to it. G-CSF can prevent caspase 3 activation in Schwann cells in the short-term, but does not detectably affect the inflammatory response, nor improve early or late axonal outgrowth or functional recovery. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Sustained Local Release of Methylprednisolone From a Thiol-Acrylate Poly(Ethylene Glycol) Hydrogel for Treating Chronic Compressive Radicular Pain.

Science.gov (United States)

Slotkin, Jonathan R; Ness, Jennifer K; Snyder, Kristin M; Skiles, Amanda A; Woodard, Eric J; OʼShea, Timothy; Layer, Rick T; Aimetti, Alex A; Toms, Steven A; Langer, Robert; Tapinos, Nikos

2016-04-01

A preclinical animal model of chronic ligation of the sciatic nerve was used to compare the effectiveness of a slow-release hydrogel carrying methylprednisolone to methylprednisolone injection alone, which simulates the current standard of care for chronic compressive radiculopathy (CR). To extend the short-term benefits of steroid injections by using a nonswelling, biodegradable hydrogel as carrier to locally release methylprednisolone in a regulated and sustained way at the site of nerve compression. CR affects millions worldwide annually, and is a cause of costly disability with significant societal impact. Currently, a leading nonsurgical therapy involves epidural injection of steroids to temporarily alleviate the pain associated with CR. However, an effective way to extend the short-term effect of steroid treatment to address the chronic component of CR does not exist. We induced chronic compression injury of the sciatic nerves of rats by permanent ligation. Forty-eight hours later we injected our methylprednisolone infused hydrogel and assessed the effectiveness of our treatment for 4 weeks. We quantified mechanical hyperalgesia using a Dynamic Plantar Aesthesiometer (Ugo Basile, Stoelting Co., IL, USA), whereas gait analysis was conducted using the Catwalk automated gait analysis platform (Noldus, Leesburg, VA, USA). Macrophage staining was performed with immunohistochemistry and quantification of monocyte chemoattractant protein-1 in sciatic nerve lysates was performed with multiplex immunoassay using a SECTOR Imager 2400A (Meso Scale Discovery, Rockville, MA, USA). We demonstrate that using the hydrogel to deliver methylprednisolone results in significant (P pain in an animal model of chronic CR. Our steroid-infused hydrogel could be an effective extender of the short-term benefits of epidural steroid injections for patients with chronic compression-induced radicular pain. N/A.

Optic Nerve Injury in a Patient with Chronic Allergic Conjunctivitis

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Ribhi Hazin

2014-01-01

Full Text Available Manipulation of the optic nerve can lead to irreversible vision changes. We present a patient with a past medical history of skin allergy and allergic conjunctivitis (AC who presented with insidious unexplained unilateral vision loss. Physical exam revealed significant blepharospasm, mild lid edema, bulbar conjunctival hyperemia, afferent pupillary defect, and slight papillary hypertrophy. Slit lamp examination demonstrated superior and inferior conjunctival scarring as well as superior corneal scarring but no signs of external trauma or neurological damage were noted. Conjunctival cultures and cytologic evaluation demonstrated significant eosinophilic infiltration. Subsequent ophthalmoscopic examination revealed optic nerve atrophy. Upon further questioning, the patient admitted to vigorous itching of the affected eye for many months. Given the presenting symptoms, history, and negative ophthalmological workup, it was determined that the optic nerve atrophy was likely secondary to digital pressure from vigorous itching. Although AC can be a significant source of decreased vision via corneal ulceration, no reported cases have ever described AC-induced vision loss of this degree from vigorous itching and chronic pressure leading to optic nerve damage. Despite being self-limiting in nature, allergic conjunctivitis should be properly managed as extreme cases can result in mechanical compression of the optic nerve and compromise vision.

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration.

Science.gov (United States)

Yu, Qing; Zhang, She-Hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-Dong

2017-10-01

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.

Diagnostic imaging of compression neuropathy; Bildgebende Diagnostik von Nervenkompressionssyndromen

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Weishaupt, D.; Andreisek, G. [Universitaetsspital, Institut fuer Diagnostische Radiologie, Zuerich (Switzerland)

2007-03-15

Compression-induced neuropathy of peripheral nerves can cause severe pain of the foot and ankle. Early diagnosis is important to institute prompt treatment and to minimize potential injury. Although clinical examination combined with electrophysiological studies remain the cornerstone of the diagnostic work-up, in certain cases, imaging may provide key information with regard to the exact anatomic location of the lesion or aid in narrowing the differential diagnosis. In other patients with peripheral neuropathies of the foot and ankle, imaging may establish the etiology of the condition and provide information crucial for management and/or surgical planning. MR imaging and ultrasound provide direct visualization of the nerve and surrounding abnormalities. Bony abnormalities contributing to nerve compression are best assessed by radiographs and CT. Knowledge of the anatomy, the etiology, typical clinical findings, and imaging features of peripheral neuropathies affecting the peripheral nerves of the foot and ankle will allow for a more confident diagnosis. (orig.) [German] Kompressionsbedingte Schaedigungen peripherer Nerven koennen die Ursache hartnaeckiger Schmerzen im Bereich des Sprunggelenks und Fusses sein. Eine fruehzeitige Diagnose ist entscheidend, um den Patienten der richtigen Therapie zuzufuehren und potenzielle Schaedigungen zu vermeiden oder zu verringern. Obschon die klinische Untersuchung und die elektrophysiologische Abklaerungen die wichtigsten Elemente der Diagnostik peripherer Nervenkompressionssyndrome sind, kann die Bildgebung entscheidend sein, wenn es darum geht, die Hoehe des Nervenschadens festzulegen oder die Differenzialdiagnose einzugrenzen. In gewissen Faellen kann durch Bildgebung sogar die Ursache der Nervenkompression gefunden werden. In anderen Faellen ist die Bildgebung wichtig bei der Therapieplanung, insbesondere dann, wenn die Laesion chirurgisch angegangen wird. Magnetresonanztomographie (MRT) und Sonographie ermoeglichen eine

Right-sided vagus nerve stimulation inhibits induced spinal cord seizures.

Science.gov (United States)

Tubbs, R Shane; Salter, E George; Killingsworth, Cheryl; Rollins, Dennis L; Smith, William M; Ideker, Raymond E; Wellons, John C; Blount, Jeffrey P; Oakes, W Jerry

2007-01-01

We have previously shown that left-sided vagus nerve stimulation results in cessation of induced spinal cord seizures. To test our hypothesis that right-sided vagus nerve stimulation will also abort seizure activity, we have initiated seizures in the spinal cord and then performed right-sided vagus nerve stimulation in an animal model. Four pigs were anesthetized and placed in the lateral position and a small laminectomy performed in the lumbar region. Topical penicillin, a known epileptogenic drug to the cerebral cortex and spinal cord, was next applied to the dorsal surface of the exposed cord. With the exception of the control animal, once seizure activity was discernible via motor convulsion or increased electrical activity, the right vagus nerve previously isolated in the neck was stimulated. Following multiple stimulations of the vagus nerve and with seizure activity confirmed, the cord was transected in the midthoracic region and vagus nerve stimulation performed. Right-sided vagus nerve stimulation resulted in cessation of spinal cord seizure activity in all animals. Transection of the spinal cord superior to the site of seizure induction resulted in the ineffectiveness of vagus nerve stimulation in causing cessation of seizure activity in all study animals. As with left-sided vagus nerve stimulation, right-sided vagus nerve stimulation results in cessation of induced spinal cord seizures. Additionally, the effects of right-sided vagus nerve stimulation on induced spinal cord seizures involve descending spinal pathways. These data may aid in the development of alternative mechanisms for electrical stimulation for patients with medically intractable seizures and add to our knowledge regarding the mechanism for seizure cessation following peripheral nerve stimulation.

Effect of Atorvastatin vs. Rosuvastatin on cardiac sympathetic nerve activity in non-diabetic patients with dilated cardiomyopathy

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Tsutamoto, Takayoshi; Ibe, Kunihiro [Toyosato Hospital, Toyosato, Shiga (Japan); Sakai, Hiroshi; Yamaji, Masayuki; Kawahara, Chiho; Nakae, Ichiro; Fujii, Masanori; Yamamoto, Takashi; Horie, Minoru [Shiga Univ. of Medical Science, Faculty of Medicine, Otsu, Shiga (Japan)

2011-08-15

Effects of statin therapy on cardiac sympathetic nerve activity in patients with chronic heart failure (CHF) have not previously been evaluated. To compare the effects of lipophilic atorvastatin and hydrophilic rosuvastatin on cardiac sympathetic nerve activity in CHF patients with dilated cardiomyopathy (DCM), 63 stable outpatients with DCM, who were already receiving standard therapy for CHF, were randomized to atorvastatin (n=32) or rosuvastatin (n=31). We evaluated cardiac sympathetic nerve activity by cardiac {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy, hemodynamic parameters and neurohumoral factors before and after 6 months of treatment. There were no differences in the baseline characteristics of the 2 groups. In the rosuvastatin group, there were no changes in MIBG parameters, left ventricular ejection fraction or plasma levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) after 6 months of treatment. In contrast, the atorvastatin group showed a significant increase in the delayed heart/mediastinum count ratio (2.18{+-}0.4 vs. 2.36{+-}0.4, P<0.0001), and the washout rate was significantly decreased (34.8{+-}5.7 vs. 32.6{+-}6.3%, P=0.0001) after 6 months of treatment compared with the baseline values. The plasma NT-proBNP level was also significantly decreased (729{+-}858 vs. 558{+-}747 pg/ml, P=0.0139). Lipophilic atorvastatin but not hydrophilic rosuvastatin improves cardiac sympathetic nerve activity in CHF patients with DCM. (author)

Protease signaling through protease activated receptor 1 mediate nerve activation by mucosal supernatants from irritable bowel syndrome but not from ulcerative colitis patients.

Science.gov (United States)

Buhner, Sabine; Hahne, Hannes; Hartwig, Kerstin; Li, Qin; Vignali, Sheila; Ostertag, Daniela; Meng, Chen; Hörmannsperger, Gabriele; Braak, Breg; Pehl, Christian; Frieling, Thomas; Barbara, Giovanni; De Giorgio, Roberto; Demir, Ihsan Ekin; Ceyhan, Güralp Onur; Zeller, Florian; Boeckxstaens, Guy; Haller, Dirk; Kuster, Bernhard; Schemann, Michael

2018-01-01

The causes of gastrointestinal complaints in irritable bowel syndrome (IBS) remain poorly understood. Altered nerve function has emerged as an important pathogenic factor as IBS mucosal biopsy supernatants consistently activate enteric and sensory neurons. We investigated the neurally active molecular components of such supernatants from patients with IBS and quiescent ulcerative colitis (UC). Effects of supernatants from 7 healthy controls (HC), 20 IBS and 12 UC patients on human and guinea pig submucous neurons were studied with neuroimaging techniques. We identify differentially expressed proteins with proteome analysis. Nerve activation by IBS supernatants was prevented by the protease activated receptor 1 (PAR1) antagonist SCHE79797. UC supernatants also activated enteric neurons through protease dependent mechanisms but without PAR1 involvement. Proteome analysis of the supernatants identified 204 proteins, among them 17 proteases as differentially expressed between IBS, UC and HC. Of those the four proteases elastase 3a, chymotrypsin C, proteasome subunit type beta-2 and an unspecified isoform of complement C3 were significantly more abundant in IBS compared to HC and UC supernatants. Of eight proteases, which were upregulated in IBS, the combination of elastase 3a, cathepsin L and proteasome alpha subunit-4 showed the highest prediction accuracy of 98% to discriminate between IBS and HC groups. Elastase synergistically potentiated the effects of histamine and serotonin-the two other main neuroactive substances in the IBS supernatants. A serine protease inhibitor isolated from the probiotic Bifidobacterium longum NCC2705 (SERPINBL), known to inhibit elastase-like proteases, prevented nerve activation by IBS supernatants. Proteases in IBS and UC supernatants were responsible for nerve activation. Our data demonstrate that proteases, particularly those signalling through neuronal PAR1, are biomarker candidates for IBS, and protease profiling may be used to

Renal sympathetic nerve ablation for treatment-resistant hypertension

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Krum, Henry; Schlaich, Markus; Sobotka, Paul

2013-01-01

Hypertension is a major risk factor for increased cardiovascular events with accelerated sympathetic nerve activity implicated in the pathogenesis and progression of disease. Blood pressure is not adequately controlled in many patients, despite the availability of effective pharmacotherapy. Novel procedure- as well as device-based strategies, such as percutaneous renal sympathetic nerve denervation, have been developed to improve blood pressure in these refractory patients. Renal sympathetic denervation not only reduces blood pressure but also renal as well as systemic sympathetic nerve activity in such patients. The reduction in blood pressure appears to be sustained over 3 years after the procedure, which suggests absence of re-innervation of renal sympathetic nerves. Safety appears to be adequate. This approach may also have potential in other disorders associated with enhanced sympathetic nerve activity such as congestive heart failure, chronic kidney disease and metabolic syndrome. This review will focus on the current status of percutaneous renal sympathetic nerve denervation, clinical efficacy and safety outcomes and prospects beyond refractory hypertension. PMID:23819768

Traumatic superior orbital fissure syndrome: assessment of cranial nerve recovery in 33 cases.

Science.gov (United States)

Chen, Chien-Tzung; Wang, Theresa Y; Tsay, Pei-Kwei; Huang, Faye; Lai, Jui-Pin; Chen, Yu-Ray

2010-07-01

Superior orbital fissure syndrome is a rare complication that occurs in association with craniofacial trauma. The characteristics of superior orbital fissure syndrome are attributable to a constellation of cranial nerve III, IV, and VI palsies. This is the largest series describing traumatic superior orbital fissure syndrome that assesses the recovery of individual cranial nerve function after treatment. In a review from 1988 to 2002, 33 patients with superior orbital fissure syndrome were identified from 11,284 patients (0.3 percent) with skull and facial fractures. Severity of cranial nerve injury and functional recovery were evaluated by extraocular muscle movement. Patients were evaluated on average 6 days after initial injury, and average follow-up was 11.8 months. There were 23 male patients. The average age was 31 years. The major mechanism of injury was motorcycle accident (67 percent). Twenty-two received conservative treatment, five were treated with steroids, and six patients underwent surgical decompression of the superior orbital fissure. After initial injury, cranial nerve VI suffered the most damage, whereas cranial nerve IV sustained the least. In the first 3 months, recovery was greatest in cranial nerve VI. At 9 months, function was lowest in cranial nerve VI and highest in cranial nerve IV. Eight patients (24 percent) had complete recovery of all cranial nerves. Functional recovery of all cranial nerves reached a plateau at 6 months after trauma. Cranial nerve IV suffered the least injury, whereas cranial nerve VI experienced the most neurologic deficits. Cranial nerve palsies improved to their final recovery endpoints by 6 months. Surgical decompression is considered when there is evidence of bony compression of the superior orbital fissure.

The Effect of Alkaline Activator Ratio on the Compressive Strength of Fly Ash-Based Geopolymer Paste

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Lăzărescu, A. V.; Szilagyi, H.; Baeră, C.; Ioani, A.

2017-06-01

Alkaline activation of fly ash is a particular procedure in which ash resulting from a power plant combined with a specific alkaline activator creates a solid material when dried at a certain temperature. In order to obtain desirable compressive strengths, the mix design of fly ash based geopolymer pastes should be explored comprehensively. To determine the preliminary compressive strength for fly ash based geopolymer paste using Romanian material source, various ratios of Na2SiO3 solution/ NaOH solution were produced, keeping the fly ash/alkaline activator ratio constant. All the mixes were then cured at 70 °C for 24 hours and tested at 2 and 7 days, respectively. The aim of this paper is to present the preliminary compressive strength results for producing fly ash based geopolymer paste using Romanian material sources, the effect of alkaline activators ratio on the compressive strength and studying the directions for future research.

Neurotology findings in patients with diagnosis of vascular loop of cranial nerves VIII in magnetic resonance imaging

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Grocoske, Francisco Luiz Busato

Full Text Available Introduction: The vascular compression by redundant vessels under the VIII cranial nerves has been studied since the 80's, and many authors proposed correlations between the compression and the otoneurological findings (vertigo, tinnitus, hypoacusis, audiometry and electrophysiological findings. Objective: Analyze and correlate the different signs and otoneurological symptoms, the audiological findings and its incidence over individuals with Vascular Loop (VL diagnosis of VIII cranial nerves by magnetic resonance imaging (MRI. Method: Retrospective study through the analysis of medical records of 47 patients attended in the otoneurology clinic of Clinical Hospital of UFPR. All the patients have MRI exams with compatible pictures of VL of the VIII cranial nerves. Results: The tinnitus was the most frequent symptom, in 83% of the patients, followed by hypoacusis (60% and vertigo (36%. The audiometry presented alterations in 89%, the brainstem evoked auditory potential in 33% and the vecto-electronystagmography in 17% of the patients. Was not found statistically significant relation between the buzz or hypoacusis, and the presence of VL in MRI. Only 36% of patients had complaints of vertigo, the main symptom described in theory of vascular compression of the VIII pair of nerve. As in the audiometry and in brainstem evoked auditory potential was not found a statistically significant relation between the exam and the presence of the VL in the RMI. Conclusion: The results show independence between the findings of the RMI, clinical picture and audiological results (p>0,05 suggesting that there are no exclusive and direct relation between the diagnosis of vascular loop in the MRI and the clinical picture matching.

Variant palmaris profundus enclosed by an unusual loop of the median nerve

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CHOU, HSIU-CHU; JENG, HELLEN; KO, TSUI-LING; PAI, MAN-HUI; CHANG, CHIU-YUN; WU, CHING-HSIANG

2001-01-01

According to the usual description in most anatomy texts, the median nerve in the forearm passes between the 2 heads of pronator teres. It continues distally between flexor digitorum superficialis and profundus almost to the retinaculum. Muscular branches leave the nerve near the elbow and supply all superficial muscles of the anterior part of the forearm except flexor carpi ulnaris. Many variations of the median nerve in the forearm have been reported (Urban & Krosman, 1992). The palmaris profundus is also a rare anomaly of the forearm (Dyreby & Engber, 1982). It originates from the radial side of the common flexor tendon in the proximal forearm and inserts into the undersurface of the palmar aponeurosis. The origin of palmaris profundus may be close to the median nerve and its branches, and may be involved in compressive neuropathy of the anterior interosseous nerve. Its tendon crossing through the carpal canal has been implicated in the carpal tunnel syndrome (reviewed by Lahey & Aulicino, 1986). In some cases, palmaris profundus was found enclosed in a common fascial sheath with the median nerve (Stark, 1992; Sahinoglu et al. 1994). To indicate its close association with the median nerve, the palmaris profundus was also named ‘musculus comitans nervi mediani’ (Sahinoglu et al. 1994). This article reports an unusual loop of the median nerve encircling an anomalous palmaris profundus in the forearm, which, to the best of our knowledge, has not been previously described. PMID:11693311

Slow and deep respiration suppresses steady-state sympathetic nerve activity in patients with chronic heart failure: from modeling to clinical application.

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Harada, Daisuke; Asanoi, Hidetsugu; Takagawa, Junya; Ishise, Hisanari; Ueno, Hiroshi; Oda, Yoshitaka; Goso, Yukiko; Joho, Shuji; Inoue, Hiroshi

2014-10-15

Influences of slow and deep respiration on steady-state sympathetic nerve activity remain controversial in humans and could vary depending on disease conditions and basal sympathetic nerve activity. To elucidate the respiratory modulation of steady-state sympathetic nerve activity, we modeled the dynamic nature of the relationship between lung inflation and muscle sympathetic nerve activity (MSNA) in 11 heart failure patients with exaggerated sympathetic outflow at rest. An autoregressive exogenous input model was utilized to simulate entire responses of MSNA to variable respiratory patterns. In another 18 patients, we determined the influence of increasing tidal volume and slowing respiratory frequency on MSNA; 10 patients underwent a 15-min device-guided slow respiration and the remaining 8 had no respiratory modification. The model predicted that a 1-liter, step increase of lung volume decreased MSNA dynamically; its nadir (-33 ± 22%) occurred at 2.4 s; and steady-state decrease (-15 ± 5%), at 6 s. Actually, in patients with the device-guided slow and deep respiration, respiratory frequency effectively fell from 16.4 ± 3.9 to 6.7 ± 2.8/min (P state MSNA was decreased by 31% (P state MSNA. Thus slow and deep respiration suppresses steady-state sympathetic nerve activity in patients with high levels of resting sympathetic tone as in heart failure. Copyright © 2014 the American Physiological Society.

Ultrasonographic findings of posterior interosseous nerve syndrome

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Kim, You Dong; Ha, Doo Hoe; Lee, Sang Min [Dept. of Radiology, CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of)

2017-10-15

The purpose of this study was to evaluate the ultrasonographic findings associated with posterior interosseous nerve (PIN) syndrome. Approval from the Institutional Review Board was obtained. A retrospective review of 908 patients' sonographic images of the upper extremity from January 2001 to October 2010 revealed 10 patients suspicious for a PIN abnormality (7 male and 3 female patients; mean age of 51.8±13.1 years; age range, 32 to 79 years). The ultrasonographic findings of PIN syndrome, including changes in the PIN and adjacent secondary changes, were evaluated. The anteroposterior diameter of the pathologic PIN was measured in eight patients and the anteroposterior diameter of the contralateral asymptomatic PIN was measured in six patients, all at the level immediately proximal to the proximal supinator border. The size of the pathologic nerves and contralateral asymptomatic nerves was compared using the Mann-Whitney U test. Swelling of the PIN proximal to the supinator canal by compression at the arcade of Fröhse was observed in four cases. Swelling of the PIN distal to the supinator canal was observed in one case. Loss of the perineural fat plane in the supinator canal was observed in one case. Four soft tissue masses were noted. Secondary denervation atrophy of the supinator and extensor muscles was observed in two cases. The mean anteroposterior diameter of the pathologic nerves (n=8, 1.79±0.43 mm) was significantly larger than that of the contralateral asymptomatic nerves (n=6, 1.02±0.22 mm) (P=0.003). Ultrasonography provides high-resolution images of the PIN and helps to diagnose PIN syndrome through visualization of its various causes and adjacent secondary changes.

MR imaging evaluation of suprascapular nerve entrapment

International Nuclear Information System (INIS)

Ludig, T.; Walter, F.; Roland, J.; Blum, A.; Chapuis, D.; Mole, D.

2001-01-01

The aim of this study was to assess the significance of muscular edema, atrophy, and fatty changes in the diagnosis of suprascapular nerve entrapment (SSNE), and to confirm muscular edema as the most significant sign of neuropathy. A retrospective study of 18 patients with suprascapular nerve entrapment was performed. All patients underwent electromyographic studies and MR imaging with a 1.5-T Echo Speed system (General Electric, Milwaukee, Wis.). The diagnosis of muscle edema was reached when muscles presented a high signal on T2-weighted fast spin-echo (SE) fat-suppressed images. Muscular trophicity and fatty changes were analyzed on a sagittal oblique cut using SE T1-weighted images. Intra- and inter-observer reproducibility using kappa test, sensitivity, and specificity were analyzed, together with negative and positive predictive value of each criterion. The topographic diagnosis was correct as edema affected the infraspinatus muscle alone when the suprascapular nerve was entrapped at the spinoglenoid notch. Both the supraspinatus and infraspinatus muscles were affected when nerve was compressed at the suprascapular notch. Sensitivity and specificity of muscular edema were, respectively, 94.5 and 100%. Muscular atrophy sensitivity and specificity were 81 and 80%, respectively. Fatty changes sensitivity and specificity were 25 and 96%, respectively. Muscular edema seems to be a more sensitive sign of SSNE than muscle atrophy and fatty changes when compared with EMG results. Magnetic resonance imaging can reach a positive, topographic, and etiologic diagnosis of SSNE. (orig.)

Unusual Branching Pattern of the Lateral Cord of the Brachial Plexus Associated with Neurovascular Compression; Case report

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Hitendra K. Loh

2017-03-01

Full Text Available The brachial plexus consists of a network of nerves that innervates the upper limbs and its musculature. We report a rare formation of the lateral cord of the brachial plexus observed during the dissection of a 47-year-old male cadaver at the Department of Anatomy, Vardhman Mahavir Medical College, New Delhi, India, in 2016. The lateral cord was exceptionally long with twin lateral pectoral nerves and twin lateral roots of the median nerve. The proximal lateral root of the median nerve was thin in comparison to the medial root of the median nerve. The distal lateral root of the median nerve was thicker and followed an unusual course through the coracobrachialis muscle. In the lower third of the arm, the median nerve and the brachial artery—along with its vena comitans—spanned through the brachialis muscle. Surgeons, anaesthesiologists, radiologists and anatomists should be aware of such anatomical variations as they may result in neurovascular compression.

Natural Detoxification Capacity to Inactivate Nerve Agents Sarin and VX in the Rat Blood

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Jiří Bajgar

2016-03-01

Full Text Available Background: The method of continual determination of the rat blood cholinesterase activity was developed to study the changes of the blood cholinesterases following different intervetions. Aims: The aim of this study is registration of cholinesterase activity in the rat blood and its changes to demonstrate detoxification capacity of rats to inactivate sarin or VX in vivo. Methods: The groups of female rats were premedicated (ketamine and xylazine and cannulated to a. femoralis. Continual blood sampling (0.02 ml/min and monitoring of the circulating blood cholinesterase activity were performed. Normal activity was monitored 1–2 min and then the nerve agent was administered i.m. (2× LD50. Using different time intervals of the leg compression and relaxation following the agent injection, cholinesterase activity was monitored and according to the inhibition obtained, detoxification capacity was assessed. Results: Administration of sarin to the leg, then 1 and 5 min compression and 20 min later relaxation showed that further inhibition in the blood was not observed. On the other hand, VX was able to inhibit blood cholinesterases after this intervention. Conclusions: The results demonstrated that sarin can be naturally detoxified on the contrary to VX. Described method can be used as model for other studies dealing with changes of cholinesterases in the blood following different factors.

Should we routinely expose recurrent laryngeal nerve(s) during thyroid surgery

International Nuclear Information System (INIS)

Ahmed, M.; Aurangzeb, A.; Rashid, A.Z.; Qureshi, M.A.; Iqbal, N.; Boota, M.; Ashfaq, M.

2013-01-01

Objective: To compare the frequency of recurrent laryngeal nerve(s) (RLNs) palsy after various thyroid procedures with and without identification of recurrent laryngeal nerve during the operation. Study Design: Randomized controlled trial. Place and Duration of Study: Department of Surgery, Military Hospital, Rawalpindi, from August 2008 to April 2010. Methodology: Patients undergoing indirect laryngoscopy with normal vocal cords and those with carcinoma and re-do surgery having normal vocal cord were included in the study. Patients with hoarseness of voice, abnormal vocal cord movements and with solitary nodule in the isthmus were excluded. These patients were randomly divided into 2 groups of 50 each using random number tables. RLN was identified by exposing the inferior thyroid artery and traced along its entire course in group-A. Whereas, in group-B, nerves were not identified during the operations. Immediate postoperative direct laryngoscopy was performed by a surgeon with the help of an anaesthesiologist for the assessment of vocal cords. Patients with persistent hoarseness of voice were followed-up with indirect laryngoscopy at 3 and 6 months. Results: Temporary unilateral recurrent laryngeal nerve palsies occurred in 2 (4%) patients in group-A where the voice and cord movements returned to normal in 6 months. In group-B, it occurred in 8 (16%) patients, 2 bilateral (4%) injuries requiring tracheostomy and 6 unilateral injuries (12%). Among the 2 bilateral recurrent laryngeal nerve injuries, the tracheostomy was removed in one case after 6 months with persistent hoarseness of voice but no respiratory difficulty during routine activities. Tracheostomy was permanent in the other case. Among the 6 cases of unilateral nerve injuries, the voice improved considerably in 4 cases within 6 months but in 2 cases hoarseness persisted even after 6 months. Frequency of recurrent laryngeal nerve palsies was significantly lower in group-A as compared to group-B (p = 0

Compressive myelopathy of the cervical spine in Komodo dragons (Varanus komodoensis).

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Zimmerman, Dawn M; Douglass, Michael; Sutherland-Smith, Meg; Aguilar, Roberto; Schaftenaar, Willem; Shores, Andy

2009-03-01

Cervical subluxation and compressive myelopathy appears to be a cause of morbidity and mortality in captive Komodo dragons (Varanus komodoensis). Four cases of cervical subluxation resulting in nerve root compression or spinal cord compression were identified. Three were presumptively induced by trauma, and one had an unknown inciting cause. Two dragons exhibited signs of chronic instability. Cervical vertebrae affected included C1-C4. Clinical signs on presentation included ataxia, ambulatory paraparesis or tetraparesis to tetraplegia, depression to stupor, cervical scoliosis, and anorexia. Antemortem diagnosis of compression was only confirmed with magnetic resonance imaging or computed tomography. Treatment ranged from supportive care to attempted surgical decompression. All dragons died or were euthanatized, at 4 days to 12 mo postpresentation. Studies to define normal vertebral anatomy in the species are necessary to determine whether the pathology is linked to cervical malformation, resulting in ligament laxity, subsequent instability, and subluxation.

Thermal and active fluctuations of a compressible bilayer vesicle

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Sachin Krishnan, T. V.; Yasuda, Kento; Okamoto, Ryuichi; Komura, Shigeyuki

2018-05-01

We discuss thermal and active fluctuations of a compressible bilayer vesicle by using the results of hydrodynamic theory for vesicles. Coupled Langevin equations for the membrane deformation and the density fields are employed to calculate the power spectral density matrix of membrane fluctuations. Thermal contribution is obtained by means of the fluctuation dissipation theorem, whereas active contribution is calculated from exponentially decaying time correlation functions of active random forces. We obtain the total power spectral density as a sum of thermal and active contributions. An apparent response function is further calculated in order to compare with the recent microrheology experiment on red blood cells. An enhanced response is predicted in the low-frequency regime for non-thermal active fluctuations.

Reconstruction of facial nerve injuries in children.

Science.gov (United States)

Fattah, Adel; Borschel, Gregory H; Zuker, Ron M

2011-05-01

Facial nerve trauma is uncommon in children, and many spontaneously recover some function; nonetheless, loss of facial nerve activity leads to functional impairment of ocular and oral sphincters and nasal orifice. In many cases, the impediment posed by facial asymmetry and reduced mimetic function more significantly affects the child's psychosocial interactions. As such, reconstruction of the facial nerve affords great benefits in quality of life. The therapeutic strategy is dependent on numerous factors, including the cause of facial nerve injury, the deficit, the prognosis for recovery, and the time elapsed since the injury. The options for treatment include a diverse range of surgical techniques including static lifts and slings, nerve repairs, nerve grafts and nerve transfers, regional, and microvascular free muscle transfer. We review our strategies for addressing facial nerve injuries in children.

Median nerve neuropathy in the forearm due to recurrence of anterior wrist ganglion that originates from the scaphotrapezial joint: Case Report

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Okada Kiyoshi

2012-01-01

Full Text Available Abstract Background Median nerve neuropathy caused by compression from a tumor in the forearm is rare. Cases with anterior wrist ganglion have high recurrence rates despite surgical treatment. Here, we report the recurrence of an anterior wrist ganglion that originated from the Scaphotrapezial joint due to incomplete resection and that caused median nerve neuropathy in the distal forearm. Case presentation A 47-year-old right-handed housewife noted the appearance of soft swelling on the volar aspect of her left distal forearm, and local resection surgery was performed twice at another hospital. One year after the last surgery, the swelling reappeared and was associated with numbness and pain in the radial volar aspect of the hand. Magnetic resonance imaging revealed that the multicystic lesion originated from the Scaphotrapezial joint and had expanded beyond the wrist. Exploration of the left median nerve showed that it was compressed by a large ovoid cystic lesion at the distal forearm near the proximal end of the carpal tunnel. We resected the cystic lesion to the Scaphotrapezial joint. Her symptoms disappeared 1 week after surgery, and complications or recurrent symptoms were absent 13 months after surgery. Conclusions A typical median nerve compression was caused by incomplete resection of an anterior wrist ganglion, which may have induced widening of the cyst. Cases with anterior wrist ganglion have high recurrence rates and require extra attention in their treatment.

MR imaging of the lumbar disk herniation : relationship between the direction of herniated disc and pressure effect on nerve root and dural sac

International Nuclear Information System (INIS)

Cha, B. H.; Shon, M. Y.; Kim, K. W.; Lim, M. A.; Kwon, K. R; Kim, S. S.

1996-01-01

To evaluate the relationship between the direction of herniated disc and pressure effect on nerve root and dural sac, as seen on MRI. We retrospectively reviewed lumbar spine MR images of 122 cases of lumbar disk herniation 75 patients MRI findings were analyzed with regard to the relationship between the direction of the herniated disc and pressure effect on nerve root and dural sac. Pressure effect on nerve root and dural sac was arbitrarily divided into three types. Type I was defined as zero or minimal compression of nerve roots or thecal sac by the herniated disc ; type II was defined as mild to moderate compression, while III was defined as severe compression or displacement of nerve roots and/or thecal sac. Of the 122 cases seen in these 75 patients, 97(80%) were observed at L4-5 and L5-S1. The central type(71cases ; 58%) was more frequently observed than the posterolateral type(48cases ; 40%) or lateral type(3cases ; 2%). The totals of types I, II, and III were 44(36%), 43(35%) and 35 cases(29%), respectively. Seventy-seven %(34/44) of type I and 65%(28/43) of type II were of the central type but for type III, the corresponding figure was only 26%(9/35). On MR imaging, most of lumbar disk herniations were observed at L4-5 and L5-S1, with a predominance of the central type rather than the posterolateral one. Most of the central types were either type I or type II

1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag.

Science.gov (United States)

Islam, Shahidul; Haque, Asadul; Bui, Ha Hong

2016-04-15

Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS) cured up to 365 days. The void ratio-logarithm of pressure (e-logσ') behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis.

Implantable electrode for recording nerve signals in awake animals

Science.gov (United States)

Ninomiya, I.; Yonezawa, Y.; Wilson, M. F.

1976-01-01

An implantable electrode assembly consisting of collagen and metallic electrodes was constructed to measure simultaneously neural signals from the intact nerve and bioelectrical noises in awake animals. Mechanical artifacts, due to bodily movement, were negligibly small. The impedance of the collagen electrodes, measured in awake cats 6-7 days after implantation surgery, ranged from 39.8-11.5 k ohms at a frequency range of 20-5 kHz. Aortic nerve activity and renal nerve activity, measured in awake conditions using the collagen electrode, showed grouped activity synchronous with the cardiac cycle. Results indicate that most of the renal nerve activity was from postganglionic sympathetic fibers and was inhibited by the baroceptor reflex in the same cardiac cycle.

Normal and sonographic anatomy of selected peripheral nerves. Part I: Sonohistology and general principles of examination, following the example of the median nerve

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Berta Kowalska

2012-06-01

Full Text Available Ultrasonography is an established method for imaging peripheral nerves. It serves to supplement the physical examination, electromyography, and magnetic resonance imaging. It enables the identification of post-traumatic changes of nerves, neuropathies secondary to compression syndromes, inflammatory or neoplastic nerve lesions as well as the evaluation of postoperative complications. In certain situations, this technique is the imaging method of choice. It is increasingly used in anesthesiology for regional anesthesia. As in the case of other ultrasound imaging studies, the examination of peripheral nerves is non-invasive, well-tolerated by patients, and relatively inexpensive. This article presents the histological structure of peripheral nerves and their appearance in ultrasonography. It also presents the examination technique, following the example of the median nerve, and includes a series of diagrams and ultrasound images. The interpretation of the shape, echogenicity, thickness and vascularity of nerves is described, as well as their relation to the surrounding tissues. The “elevator technique”, which consists of locating a set nerve at a characteristic anatomic point, and following it proximally or distally, has been explained. The undisputed benefits of the ultrasound examination have been presented, including its advantages over other diagnostic methods. These advantages include the dynamic component of the ultrasound examination and the possibility of correlating the patient’s symptoms with the ultrasound images. As an example, the proper anatomy and the ultrasonographic appearance of the median nerve were described. This nerve’s course is presented, its divisions, and characteristic reference points, so as to facilitate its location and identification, and enable subsequent use of the aforementioned “elevator technique”. This article opens a series of publications concerning anatomy, technique of examination and

HPLC-QTOF-MS method for quantitative determination of active compounds in an anti-cellulite herbal compress

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Ngamrayu Ngamdokmai

2017-08-01

Full Text Available A herbal compress used in Thai massage has been modified for use in cellulite treatment. Its main active ingredients were ginger, black pepper, java long pepper, tea and coffee. The objective of this study was to develop and validate an HPLCQTOF-MS method for determining its active compounds, i.e., caffeine, 6-gingerol, and piperine in raw materials as well as in the formulation together with the flavouring agent, camphor. The four compounds were chromatographically separated. The analytical method was validated through selectivity, intra-, inter day precision, accuracy and matrix effect. The results showed that the herbal compress contained caffeine (2.16 mg/g, camphor (106.15 mg/g, 6-gingerol (0.76 mg/g, and piperine (4.19 mg/g. The chemical stability study revealed that herbal compresses retained >80% of their active compounds after 1 month of storage at ambient conditions. Our method can be used for quality control of the herbal compress and its raw materials.

Transcutaneous electrical nerve stimulation (TENS) improves the rest-activity rhythm in midstage Alzheimer's disease

NARCIS (Netherlands)

Scherder, E. J.; van Someren, E. J.; Swaab, D. F.

1999-01-01

Nightly restlessness in patients with Alzheimer's disease (AD) is probably due to a disorder of circadian rhythms. Transcutaneous electrical nerve stimulation (TENS) was previously reported to increase the strength of coupling of the circadian rest activity rhythm to Zeitgebers in early stage

Origin and pharmacological response of atrial tachyarrhythmias induced by activation of mediastinal nerves in canines.

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Armour, J Andrew; Richer, Louis-Philippe; Pagé, Pierre; Vinet, Alain; Kus, Teresa; Vermeulen, Michel; Nadeau, Réginald; Cardinal, René

2005-03-31

We sought to determine the sites of origin of atrial tachyarrhythmias induced by activating mediastinal nerves, as well as the response of such arrhythmias to autonomic modulation. Under general anaesthesia, atrioventricular block was induced after thoracotomy in 19 canines. Brief trains of 5 electrical stimuli were delivered to right-sided mediastinal nerves during the atrial refractory period. Unipolar electrograms were recorded from 191 right and left atrial epicardial sites under several conditions, i.e. (i) with intact nervous systems and following (ii) acute decentralization of the intrathoracic nervous system or administration of (iii) atropine, (iv) timolol, (v) hexamethonium. Concomitant right atrial endocardial mapping was performed in 7 of these dogs. Mediastinal nerve stimulation consistently initiated bradycardia followed by atrial tachyarrhythmias. In the initial tachyarrhythmia beats, early epicardial breakthroughs were identified in the right atrial free wall (28/50 episodes) or Bachmann bundle region (22/50), which corresponded to endocardial sites of origin associated with the right atrial subsidiary pacemaker complex, i.e. the crista terminalis and dorsal locations including the right atrial aspect of the interatrial septum. Neuronally induced responses were eliminated by atropine, modified by timolol and unaffected by acute neuronal decentralization. After hexamethonium, responses to extra-pericardial but not intra-pericardial nerve stimulation were eliminated. It is concluded that concomitant activation of cholinergic and adrenergic efferent intrinsic cardiac neurons induced by right-sided efferent neuronal stimulation initiates atrial tachyarrhythmias that originate from foci anatomically related to the right atrial pacemaker complex and tissues underlying major atrial ganglionated plexuses.

Median nerve trauma in a rat model of work-related musculoskeletal disorder.

Science.gov (United States)

Clark, Brian D; Barr, Ann E; Safadi, Fayez F; Beitman, Lisa; Al-Shatti, Talal; Amin, Mamta; Gaughan, John P; Barbe, Mary F

2003-07-01

Anatomical and physiological changes were evaluated in the median nerves of rats trained to perform repetitive reaching. Motor degradation was evident after 4 weeks. ED1-immunoreactive macrophages were seen in the transcarpal region of the median nerve of both forelimbs by 5-6 weeks. Fibrosis, characterized by increased immunoexpression of collagen type I by 8 weeks and connective tissue growth factor by 12 weeks, was evident. The conduction velocity (NCV) within the carpal tunnel showed a modest but significant decline after 9-12 weeks. The lowest NCV values were found in animals that refused to participate in the task for the full time available. Thus, both anatomical and physiological signs of progressive tissue damage were present in this model. These results, together with other recent findings indicate that work-related carpal tunnel syndrome develops through mechanisms that include injury, inflammation, fibrosis and subsequent nerve compression.

1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag

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Shahidul Islam

2016-04-01

Full Text Available Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS cured up to 365 days. The void ratio-logarithm of pressure (e-logσ′ behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD and scanning electron microscopy (SEM analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis.

Nerve Blocks

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... News Physician Resources Professions Site Index A-Z Nerve Blocks A nerve block is an injection to ... the limitations of Nerve Block? What is a Nerve Block? A nerve block is an anesthetic and/ ...

Inhibition of micturition reflex by activation of somatic afferents in posterior femoral cutaneous nerve.

Science.gov (United States)

Tai, Changfeng; Shen, Bing; Mally, Abhijith D; Zhang, Fan; Zhao, Shouguo; Wang, Jicheng; Roppolo, James R; de Groat, William C

2012-10-01

This study determined if activation of somatic afferents in posterior femoral cutaneous nerve (PFCN) could modulate the micturition reflex recorded under isovolumetric conditions in α-chloralose anaesthetized cats. PFCN stimulation inhibited reflex bladder activity and significantly (P acid (AA). The optimal frequency for PFCN stimulation-induced bladder inhibition was between 3 and 10 Hz, and a minimal stimulation intensity of half of the threshold for inducing anal twitching was required. Bilateral pudendal nerve transection eliminated PFCN stimulation-induced anal twitching but did not change the stimulation-induced bladder inhibition, excluding the involvement of pudendal afferent or efferent axons in PFCN afferent inhibition.Mechanical or electrical stimulation on the skin surface in the PFCN dermatome also inhibited bladder activity. Prolonged (2 × 30 min) PFCN stimulation induced a post-stimulation inhibition that persists for at least 2 h. This study revealed a new cutaneous-bladder reflex activated by PFCN afferents. Although the mechanisms and physiological functions of this cutaneous-bladder reflex need to be further studied, our data raise the possibility that stimulation of PFCN afferents might be useful clinically for the treatment of overactive bladder symptoms.

Nerve cell-mimicking liposomes as biosensor for botulinum neurotoxin complete physiological activity

Energy Technology Data Exchange (ETDEWEB)

Weingart, Oliver G., E-mail: Oliver.Weingart@hest.ethz.ch; Loessner, Martin J.

2016-12-15

Botulinum neurotoxins (BoNT) are the most toxic substances known, and their neurotoxic properties and paralysing effects are exploited for medical treatment of a wide spectrum of disorders. To accurately quantify the potency of a pharmaceutical BoNT preparation, its physiological key activities (binding to membrane receptor, translocation, and proteolytic degradation of SNARE proteins) need to be determined. To date, this was only possible using animal models, or, to a limited extent, cell-based assays. We here report a novel in vitro system for BoNT/B analysis, based on nerve-cell mimicking liposomes presenting motoneuronal membrane receptors required for BoNT binding. Following triggered membrane translocation of the toxin's Light Chain, the endopeptidase activity can be quantitatively monitored employing a FRET-based reporter assay within the functionalized liposomes. We were able to detect BoNT/B physiological activity at picomolar concentrations in short time, opening the possibility for future replacement of animal experimentation in pharmaceutical BoNT testing. - Highlights: • A cell-free in vitro system was used to measure BoNT/B physiological function. • The system relies on nerve-cell mimicking liposomes as a novel detection system. • A FRET-based reporter assay is used as final readout of the test system. • BoNT/B physiological activity was detected at picogram quantities in short time. • The method opens the possibility to replace animal experimentation in BoNT testing.

Nerve cell-mimicking liposomes as biosensor for botulinum neurotoxin complete physiological activity

International Nuclear Information System (INIS)

Weingart, Oliver G.; Loessner, Martin J.

2016-01-01

Botulinum neurotoxins (BoNT) are the most toxic substances known, and their neurotoxic properties and paralysing effects are exploited for medical treatment of a wide spectrum of disorders. To accurately quantify the potency of a pharmaceutical BoNT preparation, its physiological key activities (binding to membrane receptor, translocation, and proteolytic degradation of SNARE proteins) need to be determined. To date, this was only possible using animal models, or, to a limited extent, cell-based assays. We here report a novel in vitro system for BoNT/B analysis, based on nerve-cell mimicking liposomes presenting motoneuronal membrane receptors required for BoNT binding. Following triggered membrane translocation of the toxin's Light Chain, the endopeptidase activity can be quantitatively monitored employing a FRET-based reporter assay within the functionalized liposomes. We were able to detect BoNT/B physiological activity at picomolar concentrations in short time, opening the possibility for future replacement of animal experimentation in pharmaceutical BoNT testing. - Highlights: • A cell-free in vitro system was used to measure BoNT/B physiological function. • The system relies on nerve-cell mimicking liposomes as a novel detection system. • A FRET-based reporter assay is used as final readout of the test system. • BoNT/B physiological activity was detected at picogram quantities in short time. • The method opens the possibility to replace animal experimentation in BoNT testing.

Anoxia increases potassium conductance in hippocampal nerve cells.

Science.gov (United States)

Hansen, A J; Hounsgaard, J; Jahnsen, H

1982-07-01

The effect of anoxia on nerve cell function was studied by intra- and extracellular microelectrode recordings from the CA1 and CA3 region in guinea pig hippocampal slices. Hyperpolarization and concomitant reduction of the nerve cell input resistance was observed early during anoxia. During this period the spontaneous activity first disappeared, then the evoked activity gradually disappeared. The hyperpolarization was followed by depolarization and an absence of a measurable input resistance. All the induced changes were reversed when the slice was reoxygenated. Reversal of the electro-chemical gradient for Cl- across the nerve cell membrane did not affect the course of events during anoxia. Aminopyridines blocked the anoxic hyperpolarization and attenuated the decrease of membrane resistance, but had no effect on the later depolarization. Blockers of synaptic transmission. Mn++, Mg++ and of Na+-channels (TTX) were without effect on the nerve cell changes during anoxia. It is suggested that the reduction of nerve cell excitability in anoxia is primarily due to increased K+-conductance. Thus, the nerve cells are hyperpolarized and the input resistance reduced, causing higher threshold and reduction of synaptic potentials. The mechanism of the K+-conductance activation is unknown at present.

Extramedullary hematopoiesis within the clivus: an unusual cause of lower cranial nerve palsy.

Science.gov (United States)

Reames, Davis L; Lindstrom, Katherine; Raghavan, Prashant; Jane, John

2010-12-01

We report one year follow up of a case of extramedullary hematopoiesis within the clivus. The imaging findings, brief clinical course, and endoscopic transphenoidal approach are described. A 29-year-old female with thalassemia developed worsening cranial nerve signs. After imaging studies discovered a large clival mass, she underwent endoscopic transphenoidal biopsy of the lesion. Neural compression from exuberant erythrogenesis within tissue normally quiescent of red blood cell production was found to be the etiology of her neural deficit. Treatment for this condition is generally non-operative unless significant neural compression is present. Radiotherapy and anti-neoplastic agents have been used with success.

Functional restoration of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization utilizing the functional spinal accessory nerve.

Science.gov (United States)

Yang, Ming-liang; Li, Jian-jun; Zhang, Shao-cheng; Du, Liang-jie; Gao, Feng; Li, Jun; Wang, Yu-ming; Gong, Hui-ming; Cheng, Liang

2011-08-01

The authors report a case of functional improvement of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization using a functional spinal accessory nerve. Complete spinal cord injury at the C-2 level was diagnosed in a 44-year-old man. Left diaphragm activity was decreased, and the right diaphragm was completely paralyzed. When the level of metabolism or activity (for example, fever, sitting, or speech) slightly increased, dyspnea occurred. The patient underwent neurotization of the right phrenic nerve with the trapezius branch of the right spinal accessory nerve at 11 months postinjury. Four weeks after surgery, training of the synchronous activities of the trapezius muscle and inspiration was conducted. Six months after surgery, motion was observed in the previously paralyzed right diaphragm. The lung function evaluation indicated improvements in vital capacity and tidal volume. This patient was able to sit in a wheelchair and conduct outdoor activities without assisted ventilation 12 months after surgery.

Unilateral Hypoglossal Nerve Palsy after Use of the Laryngeal Mask Airway Supreme

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Kenichi Takahoko

2014-01-01

Full Text Available Purpose. Hypoglossal nerve palsy after use of the laryngeal mask airway (LMA is an exceptionally rare complication. We present the first case of unilateral hypoglossal nerve palsy after use of the LMA Supreme. Clinical Features. A healthy 67-year-old female was scheduled for a hallux valgus correction under general anesthesia combined with femoral and sciatic nerve blocks. A size 4 LMA Supreme was inserted successfully at the first attempt and the cuff was inflated with air at an intracuff pressure of 60 cmH2O using cuff pressure gauge. Anesthesia was maintained with oxygen, nitrous oxide (67%, and sevoflurane under spontaneous breathing. The surgery was uneventful and the duration of anesthesia was two hours. The LMA was removed as the patient woke and there were no immediate postoperative complications. The next morning, the patient complained of dysarthria and dysphasia. These symptoms were considered to be caused by the LMA compressing the nerve against the hyoid bone. Conservative treatment was chosen and the paralysis recovered completely after 5 months. Conclusion. Hypoglossal nerve injury may occur despite correct positioning of the LMA under the appropriate intracuff pressure. A follow-up period of at least 6 months should be taken into account for the recovery.

Use of Processed Nerve Allografts to Repair Nerve Injuries Greater Than 25 mm in the Hand.

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Rinker, Brian; Zoldos, Jozef; Weber, Renata V; Ko, Jason; Thayer, Wesley; Greenberg, Jeffrey; Leversedge, Fraser J; Safa, Bauback; Buncke, Gregory

2017-06-01

Processed nerve allografts (PNAs) have been demonstrated to have improved clinical results compared with hollow conduits for reconstruction of digital nerve gaps less than 25 mm; however, the use of PNAs for longer gaps warrants further clinical investigation. Long nerve gaps have been traditionally hard to study because of low incidence. The advent of the RANGER registry, a large, institutional review board-approved, active database for PNA (Avance Nerve Graft; AxoGen, Inc, Alachua, FL) has allowed evaluation of lower incidence subsets. The RANGER database was queried for digital nerve repairs of 25 mm or greater. Demographics, injury, treatment, and functional outcomes were recorded on standardized forms. Patients younger than 18 and those lacking quantitative follow-up data were excluded. Recovery was graded according to the Medical Research Council Classification for sensory function, with meaningful recovery defined as S3 or greater level. Fifty digital nerve injuries in 28 subjects were included. There were 22 male and 6 female subjects, and the mean age was 45. Three patients gave a previous history of diabetes, and there were 6 active smokers. The most commonly reported mechanisms of injury were saw injuries (n = 13), crushing injuries (n = 9), resection of neuroma (n = 9), amputation/avulsions (n = 8), sharp lacerations (n = 7), and blast/gunshots (n = 4). The average gap length was 35 ± 8 mm (range, 25-50 mm). Recovery to the S3 or greater level was reported in 86% of repairs. Static 2-point discrimination (s2PD) and Semmes-Weinstein monofilament (SWF) were the most common completed assessments. Mean s2PD in 24 repairs reporting 2PD data was 9 ± 4 mm. For the 38 repairs with SWF data, protective sensation was reported in 33 repairs, deep pressure in 2, and no recovery in 3. These data compared favorably with historical data for nerve autograft repairs, with reported levels of meaningful recovery of 60% to 88%. There were no reported adverse effects

Large A-fiber activity is required for microglial proliferation and p38 MAPK activation in the spinal cord: different effects of resiniferatoxin and bupivacaine on spinal microglial changes after spared nerve injury

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Decosterd Isabelle

2009-09-01

Full Text Available Abstract Background After peripheral nerve injury, spontaneous ectopic activity arising from the peripheral axons plays an important role in inducing central sensitization and neuropathic pain. Recent evidence indicates that activation of spinal cord microglia also contributes to the development of neuropathic pain. In particular, activation of p38 mitogen-activated protein kinase (MAPK in spinal microglia is required for the development of mechanical allodynia. However, activity-dependent activation of microglia after nerve injury has not been fully addressed. To determine whether spontaneous activity from C- or A-fibers is required for microglial activation, we used resiniferatoxin (RTX to block the conduction of transient receptor potential vanilloid subtype 1 (TRPV1 positive fibers (mostly C- and Aδ-fibers and bupivacaine microspheres to block all fibers of the sciatic nerve in rats before spared nerve injury (SNI, and observed spinal microglial changes 2 days later. Results SNI induced robust mechanical allodynia and p38 activation in spinal microglia. SNI also induced marked cell proliferation in the spinal cord, and all the proliferating cells (BrdU+ were microglia (Iba1+. Bupivacaine induced a complete sensory and motor blockade and also significantly inhibited p38 activation and microglial proliferation in the spinal cord. In contrast, and although it produced an efficient nociceptive block, RTX failed to inhibit p38 activation and microglial proliferation in the spinal cord. Conclusion (1 Blocking peripheral input in TRPV1-positive fibers (presumably C-fibers is not enough to prevent nerve injury-induced spinal microglial activation. (2 Peripheral input from large myelinated fibers is important for microglial activation. (3 Microglial activation is associated with mechanical allodynia.

Advanced and standardized evaluation of neurovascular compression syndromes

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Hastreiter, Peter; Vega Higuera, Fernando; Tomandl, Bernd; Fahlbusch, Rudolf; Naraghi, Ramin

2004-05-01

Caused by a contact between vascular structures and the root entry or exit zone of cranial nerves neurovascular compression syndromes are combined with different neurological diseases (trigeminal neurolagia, hemifacial spasm, vertigo, glossopharyngeal neuralgia) and show a relation with essential arterial hypertension. As presented previously, the semi-automatic segmentation and 3D visualization of strongly T2 weighted MR volumes has proven to be an effective strategy for a better spatial understanding prior to operative microvascular decompression. After explicit segmentation of coarse structures, the tiny target nerves and vessels contained in the area of cerebrospinal fluid are segmented implicitly using direct volume rendering. However, based on this strategy the delineation of vessels in the vicinity of the brainstem and those at the border of the segmented CSF subvolume are critical. Therefore, we suggest registration with MR angiography and introduce consecutive fusion after semi-automatic labeling of the vascular information. Additionally, we present an approach of automatic 3D visualization and video generation based on predefined flight paths. Thereby, a standardized evaluation of the fused image data is supported and the visualization results are optimally prepared for intraoperative application. Overall, our new strategy contributes to a significantly improved 3D representation and evaluation of vascular compression syndromes. Its value for diagnosis and surgery is demonstrated with various clinical examples.

Raman spectroscopic detection of peripheral nerves towards nerve-sparing surgery

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Minamikawa, Takeo; Harada, Yoshinori; Takamatsu, Tetsuro

2017-02-01

The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery, namely nerve-sparing surgery, is now promising technique to avoid functional deficits of the limbs and organs following surgery as an aspect of the improvement of quality of life of patients. Detection of peripheral nerves including myelinated and unmyelinated nerves is required for the nerve-sparing surgery; however, conventional nerve identification scheme is sometimes difficult to identify peripheral nerves due to similarity of shape and color to non-nerve tissues or its limited application to only motor peripheral nerves. To overcome these issues, we proposed a label-free detection technique of peripheral nerves by means of Raman spectroscopy. We found several fingerprints of peripheral myelinated and unmyelinated nerves by employing a modified principal component analysis of typical spectra including myelinated nerve, unmyelinated nerve, and adjacent tissues. We finally realized the sensitivity of 94.2% and the selectivity of 92.0% for peripheral nerves including myelinated and unmyelinated nerves against adjacent tissues. Although further development of an intraoperative Raman spectroscopy system is required for clinical use, our proposed approach will serve as a unique and powerful tool for peripheral nerve detection for nerve-sparing surgery in the future.

Beneficial effects of gamma linolenic acid supplementation on nerve conduction velocity, Na+, K+ ATPase activity, and membrane fatty acid composition in sciatic nerve of diabetic rats.

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Coste, T; Pierlovisi, M; Leonardi, J; Dufayet, D; Gerbi, A; Lafont, H; Vague, P; Raccah, D

1999-07-01

Metabolic and vascular abnormalities are implicated in the pathogenesis of diabetic neuropathy. Two principal metabolic defects are altered lipid metabolism resulting from the impairment of delta-6-desaturase, which converts linoleic acid (LA) into gamma linolenic acid (GLA), and reduced nerve Na+, K+ ATPase activity. This reduction may be caused by a lack of incorporation of (n-6) fatty acids in membrane phospholipids. Because this ubiquitous enzyme maintains the membrane electrical potential and allows repolarization, disturbances in its activity can alter the process of nerve conduction velocity (NCV). We studied the effects of supplementation with GLA (260 mg per day) on NCV, fatty acid phospholipid composition, and Na+, K+ ATPase activity in streptozotocin-diabetic rats. Six groups of 10 rats were studied. Two groups served as controls supplemented with GLA or sunflower oil (GLA free). Two groups with different durations of diabetes were studied: 6 weeks with no supplementation and 12 weeks supplemented with sunflower oil. To test the ability of GLA to prevent or reverse the effects of diabetes, two groups of diabetic rats were supplemented with GLA, one group for 12 weeks and one group for 6 weeks, starting 6 weeks after diabetes induction. Diabetes resulted in a 25% decrease in NCV (P < 0.0001), a 45% decrease in Na+, K+ ATPase activity (P < 0.0001), and an abnormal phospholipid fatty acid composition. GLA restored NCV both in the prevention and reversal studies and partially restored Na+, K+ ATPase activity in the preventive treatment group (P < 0.0001). These effects were accompanied by a modification of phospholipid fatty acid composition in nerve membranes. Overall, the results suggest that membrane fatty acid composition plays a direct role in NCV and confirm the beneficial effect of GLA supplementation in diabetic neuropathy.

Comparing the Efficacy of Triple Nerve Transfers with Nerve Graft Reconstruction in Upper Trunk Obstetric Brachial Plexus Injury.

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O'Grady, Kathleen M; Power, Hollie A; Olson, Jaret L; Morhart, Michael J; Harrop, A Robertson; Watt, M Joe; Chan, K Ming

2017-10-01

Upper trunk obstetric brachial plexus injury can cause profound shoulder and elbow dysfunction. Although neuroma excision with interpositional sural nerve grafting is the current gold standard, distal nerve transfers have a number of potential advantages. The goal of this study was to compare the clinical outcomes and health care costs between nerve grafting and distal nerve transfers in children with upper trunk obstetric brachial plexus injury. In this prospective cohort study, children who underwent triple nerve transfers were followed with the Active Movement Scale for 2 years. Their outcomes were compared to those of children who underwent nerve graft reconstruction. To assess health care use, a cost analysis was also performed. Twelve patients who underwent nerve grafting were compared to 14 patients who underwent triple nerve transfers. Both groups had similar baseline characteristics and showed improved shoulder and elbow function following surgery. However, the nerve transfer group displayed significantly greater improvement in shoulder external rotation and forearm supination 2 years after surgery (p The operative time and length of hospital stay were significantly lower (p the overall cost was approximately 50 percent less in the nerve transfer group. Triple nerve transfer for upper trunk obstetric brachial plexus injury is a feasible option, with better functional shoulder external rotation and forearm supination, faster recovery, and lower cost compared with traditional nerve graft reconstruction. Therapeutic, II.

Cell proliferation and apoptosis in optic nerve and brain integration centers of adult trout Oncorhynchus mykiss after optic nerve injury

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Pushchina, Evgeniya V.; Shukla, Sachin; Varaksin, Anatoly A.; Obukhov, Dmitry K.

2016-01-01

Fishes have remarkable ability to effectively rebuild the structure of nerve cells and nerve fibers after central nervous system injury. However, the underlying mechanism is poorly understood. In order to address this issue, we investigated the proliferation and apoptosis of cells in contralateral and ipsilateral optic nerves, after stab wound injury to the eye of an adult trout Oncorhynchus mykiss. Heterogenous population of proliferating cells was investigated at 1 week after injury. TUNEL labeling gave a qualitative and quantitative assessment of apoptosis in the cells of optic nerve of trout 2 days after injury. After optic nerve injury, apoptotic response was investigated, and mass patterns of cell migration were found. The maximal concentration of apoptotic bodies was detected in the areas of mass clumps of cells. It is probably indicative of massive cell death in the area of high phagocytic activity of macrophages/microglia. At 1 week after optic nerve injury, we observed nerve cell proliferation in the trout brain integration centers: the cerebellum and the optic tectum. In the optic tectum, proliferating cell nuclear antigen (PCNA)-immunopositive radial glia-like cells were identified. Proliferative activity of nerve cells was detected in the dorsal proliferative (matrix) area of the cerebellum and in parenchymal cells of the molecular and granular layers whereas local clusters of undifferentiated cells which formed neurogenic niches were observed in both the optic tectum and cerebellum after optic nerve injury. In vitro analysis of brain cells of trout showed that suspension cells compared with monolayer cells retain higher proliferative activity, as evidenced by PCNA immunolabeling. Phase contrast observation showed mitosis in individual cells and the formation of neurospheres which gradually increased during 1–4 days of culture. The present findings suggest that trout can be used as a novel model for studying neuronal regeneration. PMID:27212918

Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

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Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

2011-01-01

Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

Vascularized nerve grafts for lower extremity nerve reconstruction.

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Terzis, Julia K; Kostopoulos, Vasileios K

2010-02-01

Vascularized nerve grafts (VNG) were introduced in 1976 but since then, there have been no reports of their usage in lower extremity reconstruction systematically. The factors influencing outcomes as well as a comparison with conventional nerve grafts will be presented.Since 1981, 14 lower extremity nerve injuries in 12 patients have been reconstructed with VNG. Common peroneal nerve was injured in 12 and posterior tibial nerve in 5 patients. The level of the injury was at the knee or thigh. Twelve sural nerves were used as VNG with or without concomitant vascularized posterior calf fascia.All patients regained improved sensibility and adequate posterior tibial nerve function. For common peroneal nerve reconstructions, all patients with denervation time less than 6 months regained muscle strength of grade at least 4, even when long grafts were used for defects of 20 cm or more. Late cases, yielded inadequate muscle function even with the use of VNG.Denervation time of 6 months or less was critical for reconstruction with vascularized nerve graft. Not only the results were statistically significant compared with late cases, but also all early operated patients achieved excellent results. VNG are strongly recommended in traction avulsion injuries of the lower extremity with lengthy nerve damage.

Matrix metalloproteinase-2 is downregulated in sciatic nerve by streptozotocin induced diabetes and/or treatment with minocycline: Implications for nerve regeneration

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Ali, Sumia; Driscoll, Heather E.; Newton, Victoria L.; Gardiner, Natalie J.

2014-01-01

Minocycline is an inhibitor of matrix metalloproteinases (MMPs) and has been shown to have analgesic effects. Whilst increased expression of MMPs is associated with neuropathic pain, MMPs also play crucial roles in Wallerian degeneration and nerve regeneration. In this study we examined the expression of MMP-2, MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1/-2 in the sciatic nerve of control and streptozotocin-induced diabetic rats treated with either vehicle or minocycline by quantitative PCR and gelatin zymography. We assessed the effects of minocycline on nerve conduction velocity and intraepidermal nerve fibre (IENF) deficits in diabetic neuropathy and investigated the effects of minocycline or MMP-2 on neurite outgrowth from primary cultures of dissociated adult rat sensory neurons. We show that MMP-2 is expressed constitutively in the sciatic nerve in vivo and treatment with minocycline or diabetes leads to downregulation of MMP-2 expression and activity. The functional consequence of this is IENF deficits in minocycline-treated nondiabetic rats and an unsupportive microenvironment for regeneration in diabetes. Minocycline reduces levels of MMP-2 mRNA and nerve growth factor-induced neurite outgrowth. Furthermore, in vivo minocycline treatment reduces preconditioning-induced in vitro neurite outgrowth following a sciatic nerve crush. In contrast, the addition of active MMP-2 facilitates neurite outgrowth in the absence of neurotrophic support and pre-treatment of diabetic sciatic nerve substrata with active MMP-2 promotes a permissive environment for neurite outgrowth. In conclusion we suggest that MMP-2 downregulation may contribute to the regenerative deficits in diabetes. Minocycline treatment also downregulates MMP-2 activity and is associated with inhibitory effects on sensory neurons. Thus, caution should be exhibited with its use as the balance between beneficial and detrimental outcomes may be critical in assessing the benefits of using

Integrated Model of the Eye/Optic Nerve Head Biomechanical Environment

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Ethier, C. R.; Feola, A.; Myers, J. G.; Nelson, E.; Raykin, J.; Samuels, B.

2017-01-01

Visual Impairment and Intracranial Pressure (VIIP) syndrome is a concern for long-duration space flight. Previously, it has been suggested that ocular changes observed in VIIP syndrome are related to the cephalad fluid shift that results in altered fluid pressures [1]. We are investigating the impact of changes in intracranial pressure (ICP) using a combination of numerical models, which simulate the effects of various environment conditions, including finite element (FE) models of the posterior eye. The specific interest is to understand how altered pressures due to gravitational changes affect the biomechanical environment of tissues of the posterior eye and optic nerve sheath. METHODS: Additional description of the numerical modeling is provided in the IWS abstract by Nelson et al. In brief, to simulate the effects of a cephalad fluid shift on the cardiovascular and ocular systems, we utilized a lumped-parameter compartment model of these systems. The outputs of this lumped-parameter model then inform boundary conditions (pressures) for a finite element model of the optic nerve head (Figure 1). As an example, we show here a simulation of postural change from supine to 15 degree head-down tilt (HDT), with primary outcomes being the predicted change in strains at the optic nerve head (ONH) region, specifically in the lamina cribrosa (LC), retrolaminar optic nerve, and prelaminar neural tissue (PLNT). The strain field can be decomposed into three orthogonal components, denoted as the first, second and third principal strains. We compare the peak tensile (first principal) and compressive (third principal) strains, since elevated strain alters cell phenotype and induces tissue remodeling. RESULTS AND CONCLUSIONS: Our lumped-parameter model predicted an IOP increase of c. 7 mmHg after 21 minutes of 15 degree HDT, which agreed with previous reports of IOP in HDT [1]. The corresponding FEM simulations predicted a relative increase in the magnitudes of the peak tensile

Autophagy is activated in compression-induced cell degeneration and is mediated by reactive oxygen species in nucleus pulposus cells exposed to compression.

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Ma, K-G; Shao, Z-W; Yang, S-H; Wang, J; Wang, B-C; Xiong, L-M; Wu, Q; Chen, S-F

2013-12-01

To determine whether autophagy contributes to the pathogenesis of degenerative disc disease (DDD) or retards the intervertebral disc (IVD) degeneration, and investigate the possible relationship between compression-induced autophagy and intracellular reactive oxygen species (ROS) in nucleus pulposus (NP) cells in vitro. The autophagosome and autophagy-related markers were used to explore the role of autophagy in rat NP cells under compressive stress, which were measured directly by electronic microscopy, monodansylcadaverine (MDC) staining, immunofluorescence, western blot, and indirectly by analyzing the impact of pharmacological inhibitors of autophagy such as 3-methyladenine (3-MA) and chloroquine (CQ). And the relationship between autophagy and apoptosis was investigated by Annexin-V/propidium iodide (PI)-fluorescein staining. In addition, ROS were measured to determine whether these factors are responsible for the development of compression-induced autophagy. Our results indicated that rat NP cells activated autophagy in response to the same strong apoptotic stimuli that triggered apoptosis by compression. Autophagy and apoptosis were interconnected and coordinated in rat NP cells exposed to compression stimuli. Compression-induced autophagy was closely related to intracellular ROS production. Enhanced degradation of damaged components of NP cells by autophagy may be a crucial survival response against mechanical overload, and extensive autophagy may trigger autophagic cell death. Regulating autophagy and reducing the generation of intracellular ROS may retard IVD degeneration. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

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2015-01-01

There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

Nerve conduction and excitability studies in peripheral nerve disorders

DEFF Research Database (Denmark)

Krarup, Christian; Moldovan, Mihai

2009-01-01

counterparts in the peripheral nervous system, in some instances without peripheral nervous system symptoms. Both hereditary and acquired demyelinating neuropathies have been studied and the effects on nerve pathophysiology have been compared with degeneration and regeneration of axons. SUMMARY: Excitability......PURPOSE OF REVIEW: The review is aimed at providing information about the role of nerve excitability studies in peripheral nerve disorders. It has been known for many years that the insight into peripheral nerve pathophysiology provided by conventional nerve conduction studies is limited. Nerve...... excitability studies are relatively novel but are acquiring an increasingly important role in the study of peripheral nerves. RECENT FINDINGS: By measuring responses in nerve that are related to nodal function (strength-duration time constant, rheobase and recovery cycle) and internodal function (threshold...

Selective activation of microglia in spinal cord but not higher cortical regions following nerve injury in adult mouse

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Shang Yuze

2008-04-01

Full Text Available Abstract Neuronal plasticity along the pathway for sensory transmission including the spinal cord and cortex plays an important role in chronic pain, including inflammatory and neuropathic pain. While recent studies indicate that microglia in the spinal cord are involved in neuropathic pain, a systematic study has not been performed in other regions of the central nervous system (CNS. In the present study, we used heterozygous Cx3cr1GFP/+mice to characterize the morphological phenotypes of microglia following common peroneal nerve (CPN ligation. We found that microglia showed a uniform distribution throughout the CNS, and peripheral nerve injury selectively activated microglia in the spinal cord dorsal horn and related ventral horn. In contrast, microglia was not activated in supraspinal regions of the CNS, including the anterior cingulate cortex (ACC, prefrontal cortex (PFC, primary and secondary somatosensory cortex (S1 and S2, insular cortex (IC, amygdala, hippocampus, periaqueductal gray (PAG and rostral ventromedial medulla (RVM. Our results provide strong evidence that nerve injury primarily activates microglia in the spinal cord of adult mice, and pain-related cortical plasticity is likely mediated by neurons.

External laryngeal nerve in thyroid surgery: is the nerve stimulator necessary?

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Aina, E N; Hisham, A N

2001-09-01

To find out the incidence and type of external laryngeal nerves during operations on the thyroid, and to assess the role of a nerve stimulator in detecting them. Prospective, non-randomised study. Teaching hospital, Malaysia. 317 patients who had 447 dissections between early January 1998 and late November 1999. Number and type of nerves crossing the cricothyroid space, and the usefulness of the nerve stimulator in finding them. The nerve stimulator was used in 206/447 dissections (46%). 392 external laryngeal nerves were seen (88%), of which 196/206 (95%) were detected with the stimulator. However, without the stimulator 196 nerves were detected out of 241 dissections (81%). The stimulator detected 47 (23%) Type I nerves (nerve > 1 cm from the upper edge of superior pole); 86 (42%) Type IIa nerves (nerve edge of superior pole); and 63 (31%) Type IIb nerves (nerve below upper edge of superior pole). 10 nerves were not detected. When the stimulator was not used the corresponding figures were 32 (13%), 113 (47%), and 51 (21%), and 45 nerves were not seen. If the nerve cannot be found we recommend dissection of capsule close to the medial border of the upper pole of the thyroid to avoid injury to the nerve. Although the use of the nerve stimulator seems desirable, it confers no added advantage in finding the nerve. In the event of uncertainty about whether a structure is the nerve, the stimulator may help to confirm it. However, exposure of the cricothyroid space is most important for good exposure in searching for the external laryngeal nerve.

Post-evaluation of the neurophaties treatment post-trauma with therapeutic laser. Model in sciatic nerve of frog

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Escobar, Antonio S.; Ocampo, Arcelia F. M.; Hernández, María G. H.; Jasso, José L. C.; Lira, Maricela O. F.; Flores, Mariana A.; Balderrama, Vicente L.

2010-05-01

The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% formalin. The latency recorded by stimulating the sciatic nerve of frog to 0.5 mA and 100 ms in groups 1 and 2 show significant differences (p000), as to the extent, if any statistically significant difference. (pparesthesia (post-traumatic neuropathy).

Chitin biological absorbable catheters bridging sural nerve grafts transplanted into sciatic nerve defects promote nerve regeneration.

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Wang, Zhi-Yong; Wang, Jian-Wei; Qin, Li-Hua; Zhang, Wei-Guang; Zhang, Pei-Xun; Jiang, Bao-Guo

2018-06-01

To investigate the efficacy of chitin biological absorbable catheters in a rat model of autologous nerve transplantation. A segment of sciatic nerve was removed to produce a sciatic nerve defect, and the sural nerve was cut from the ipsilateral leg and used as a graft to bridge the defect, with or without use of a chitin biological absorbable catheter surrounding the graft. The number and morphology of regenerating myelinated fibers, nerve conduction velocity, nerve function index, triceps surae muscle morphology, and sensory function were evaluated at 9 and 12 months after surgery. All of the above parameters were improved in rats in which the nerve graft was bridged with chitin biological absorbable catheters compared with rats without catheters. The results of this study indicate that use of chitin biological absorbable catheters to surround sural nerve grafts bridging sciatic nerve defects promotes recovery of structural, motor, and sensory function and improves muscle fiber morphology. © 2018 John Wiley & Sons Ltd.

The role of ultrasound imaging in the evaluation of peripheral nerve in systemic sclerosis (scleroderma)

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Tagliafico, Alberto; Panico, Nicoletta; Resmini, Eugenia; Derchi, Lorenzo E.; Ghio, Massimo; Martinoli, Carlo

2011-01-01

Background: Patients affected by scleroderma may complain of sensory disturbances especially in the hands. Purpose: To study the imaging features of upper limb nerves in patients affected by scleroderma (SSc). Materials and method: Twenty-five patients affected only by SSc were prospectively evaluated with high-resolution US and magnetic resonance (MRI) or computer tomography (CT) when necessary (2 patients). Median and ulnar nerves were evaluated bilaterally. Nerve conduction studies were performed in the symptomatic patients (n = 10). Results of imaging studies were correlated with disease duration, autoimmunity and immunosuppression. Nerves of SSc patients were compared with a control group of 90 patients matched for age and body mass index. Results: The prevalence of sensory disturbances revealed by clinical examination was 40%. In symptomatic SSc patients (n = 10) US evaluation revealed nerve abnormalities in 70% of cases (n = 7/10). n = 2 had a carpal tunnel syndrome. n = 5 had cubital tunnel syndrome. In two of them CT and MR were necessary to identify the compressed nerve at the level of the elbow due to the presence of calcifications. There was no association between the presence of an entrapment neuropathy and disease duration, autoantibodies and immunosuppression. Conclusion: Ultrasound, CT and MR may detect nerve abnormalities in 70% of SSc patients complaining of neurologic disturbances in the hands. The results of imaging studies support the hypothesis of a vascular dependent neuropathy in SSc.

The role of ultrasound imaging in the evaluation of peripheral nerve in systemic sclerosis (scleroderma)

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Tagliafico, Alberto, E-mail: atagliafico@sirm.org [Department of Radiology, University of Genova, Genova (Italy); Panico, Nicoletta [Division of Immunology, Department of Internal Medicine, University of Genoa, Genoa (Italy); Resmini, Eugenia [Department of Endocrinological and Medical Sciences (DiSEM), Center of Excellence for Biomedical Research, University of Genova, Genova (Italy); Derchi, Lorenzo E. [Department of Radiology, University of Genova, Genova (Italy); Ghio, Massimo [Division of Immunology, Department of Internal Medicine, University of Genoa, Genoa (Italy); Martinoli, Carlo [Department of Radiology, University of Genova, Genova (Italy)

2011-03-15

Background: Patients affected by scleroderma may complain of sensory disturbances especially in the hands. Purpose: To study the imaging features of upper limb nerves in patients affected by scleroderma (SSc). Materials and method: Twenty-five patients affected only by SSc were prospectively evaluated with high-resolution US and magnetic resonance (MRI) or computer tomography (CT) when necessary (2 patients). Median and ulnar nerves were evaluated bilaterally. Nerve conduction studies were performed in the symptomatic patients (n = 10). Results of imaging studies were correlated with disease duration, autoimmunity and immunosuppression. Nerves of SSc patients were compared with a control group of 90 patients matched for age and body mass index. Results: The prevalence of sensory disturbances revealed by clinical examination was 40%. In symptomatic SSc patients (n = 10) US evaluation revealed nerve abnormalities in 70% of cases (n = 7/10). n = 2 had a carpal tunnel syndrome. n = 5 had cubital tunnel syndrome. In two of them CT and MR were necessary to identify the compressed nerve at the level of the elbow due to the presence of calcifications. There was no association between the presence of an entrapment neuropathy and disease duration, autoantibodies and immunosuppression. Conclusion: Ultrasound, CT and MR may detect nerve abnormalities in 70% of SSc patients complaining of neurologic disturbances in the hands. The results of imaging studies support the hypothesis of a vascular dependent neuropathy in SSc.

A novel method of lengthening the accessory nerve for direct coaptation during nerve repair and nerve transfer procedures.

Science.gov (United States)

Tubbs, R Shane; Maldonado, Andrés A; Stoves, Yolanda; Fries, Fabian N; Li, Rong; Loukas, Marios; Oskouian, Rod J; Spinner, Robert J

2018-01-01

OBJECTIVE The accessory nerve is frequently repaired or used for nerve transfer. The length of accessory nerve available is often insufficient or marginal (under tension) for allowing direct coaptation during nerve repair or nerve transfer (neurotization), necessitating an interpositional graft. An attractive maneuver would facilitate lengthening of the accessory nerve for direct coaptation. The aim of the present study was to identify an anatomical method for such lengthening. METHODS In 20 adult cadavers, the C-2 or C-3 connections to the accessory nerve were identified medial to the sternocleidomastoid (SCM) muscle and the anatomy of the accessory nerve/cervical nerve fibers within the SCM was documented. The cervical nerve connections were cut. Lengths of the accessory nerve were measured. Samples of the cut C-2 and C-3 nerves were examined using immunohistochemistry. RESULTS The anatomy and adjacent neural connections within the SCM are complicated. However, after the accessory nerve was "detethered" from within the SCM and following transection, the additional length of the accessory nerve increased from a mean of 6 cm to a mean of 10.5 cm (increase of 4.5 cm) after cutting the C-2 connections, and from a mean of 6 cm to a mean length of 9 cm (increase of 3.5 cm) after cutting the C-3 connections. The additional length of accessory nerve even allowed direct repair of an infraclavicular target (i.e., the proximal musculocutaneous nerve). The cervical nerve connections were shown not to contain motor fibers. CONCLUSIONS An additional length of the accessory nerve made available in the posterior cervical triangle can facilitate direct repair or neurotization procedures, thus eliminating the need for an interpositional nerve graft, decreasing the time/distance for regeneration and potentially improving clinical outcomes.

Successful Treatment with Microvascular Decompression Surgery of a Patient with Hemiparesis Caused by Vertebral Artery Compression of the Medulla Oblongata: Case Report and Review of the Literature.

Science.gov (United States)

Ren, Jibin; Sun, Hongtao; Diao, Yunfeng; Niu, Xuegang; Wang, Hang; Wei, Zhengjun; Yuan, Fei

2017-12-01

There are few reports on hemiparesis caused by vascular medullary compression, which can occur because of dolichoectasia of the vertebrobasilar arterial system. In this article, we report a case of vertebral artery compression of the medulla oblongata in a 67-year-old woman. The patient was hypertensive, and she developed hemiparesis and intermittent spasms over 5 years. These spasms had worsened during the last year. Cranial nerve magnetic resonance imaging showed compression of the medulla oblongata by the left vertebral artery. A motor evoked potential (MEP) examination showed abnormal conduction of MEPs of bilateral toe abductors. The patient underwent microvascular decompression surgery under general anesthesia through a retrosigmoid keyhole approach. This operation led to relief of vascular compression and symptomatic improvement. Our case suggests that detailed history, imaging studies, and electrophysiologic studies help lead to a correct and early diagnosis of hemiparesis caused by vascular compression of the rostral ventrolateral medulla. Microvascular decompression surgery improves patient symptoms, and intraoperative electrophysiologic monitoring helps to avoid injury to important adjacent nerves. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of peripheral compression and auditory nerve fiber intensity coding using auditory steady-state responses

DEFF Research Database (Denmark)

Encina Llamas, Gerard; M. Harte, James; Epp, Bastian

2015-01-01

. Evaluation of these properties provides information about the health state of the system. It has been shown that a loss of outer hair cells leads to a reduction in peripheral compression. It has also recently been shown in animal studies that noise over-exposure, producing temporary threshold shifts, can....... The results indicate that the slope of the ASSR level growth function can be used to estimate peripheral compression simultaneously at four frequencies below 60 dB SPL, while the slope above 60 dB SPL may provide information about the integrity of intensity coding of low-SR fibers.......The compressive nonlinearity of the auditory system is assumed to be an epiphenomenon of a healthy cochlea and, particularly, of outer-hair cell function. Another ability of the healthy auditory system is to enable communication in acoustical environments with high-level background noises...

Increase of transcription factor EB (TFEB) and lysosomes in rat DRG neurons and their transportation to the central nerve terminal in dorsal horn after nerve injury.

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Jung, J; Uesugi, N; Jeong, N Y; Park, B S; Konishi, H; Kiyama, H

2016-01-28

In the spinal dorsal horn (DH), nerve injury activates microglia and induces neuropathic pain. Several studies clarified an involvement of adenosine triphosphate (ATP) in the microglial activation. However, the origin of ATP together with the release mechanism is unclear. Recent in vitro study revealed that an ATP marker, quinacrine, in lysosomes was released from neurite terminal of dorsal root ganglion (DRG) neurons to extracellular space via lysosomal exocytosis. Here, we demonstrate a possibility that the lysosomal ingredient including ATP released from DRG neurons by lysosomal-exocytosis is an additional source of the glial activation in DH after nerve injury. After rat L5 spinal nerve ligation (SNL), mRNA for transcription factor EB (TFEB), a transcription factor controlling lysosomal activation and exocytosis, was induced in the DRG. Simultaneously both lysosomal protein, LAMP1- and vesicular nuclear transporter (VNUT)-positive vesicles were increased in L5 DRG neurons and ipsilateral DH. The quinacrine staining in DH was increased and co-localized with LAMP1 immunoreactivity after nerve injury. In DH, LAMP1-positive vesicles were also co-localized with a peripheral nerve marker, Isolectin B4 (IB4) lectin. Injection of the adenovirus encoding mCherry-LAMP1 into DRG showed that mCherry-positive lysosomes are transported to the central nerve terminal in DH. These findings suggest that activation of lysosome synthesis including ATP packaging in DRG, the central transportation of the lysosome, and subsequent its exocytosis from the central nerve terminal of DRG neurons in response to nerve injury could be a partial mechanism for activation of microglia in DH. This lysosome-mediated microglia activation mechanism may provide another clue to control nociception and pain. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration

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2016-04-01

1 Award Number: W81XWH-11-2-0047 TITLE: Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration PRINCIPAL INVESTIGATOR: Ahmet Höke...TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-11-2-0047 Nanofiber nerve guide for peripheral nerve repair and regeneration 5b. GRANT NUMBER...goal of this collaborative research project was to develop next generation engineered nerve guide conduits (NGCs) with aligned nanofibers and

Peripheral nerve injury induces glial activation in primary motor cortex

OpenAIRE

Julieta Troncoso; Julieta Troncoso; Efraín Buriticá; Efraín Buriticá

2015-01-01

Preliminary evidence suggests that peripheral facial nerve injuries are associated with sensorimotor cortex reorganization. We have characterized facial nerve lesion-induced structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with glial cell density using a rodent facial paralysis model. First, we used adult transgenic mice expressing green fluorescent protein in microglia and yellow fluorescent protein in pyramidal neurons which were subjected to eithe...

A fine structural localization of the non-specific cholinesterase activity in glomerular nerve formations (endings).

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Dubový, P

1990-01-01

Snout glabrous skin (rhinarium) of the cat is innervated not only by typical simple lamellar corpuscles but also glomerular formations. In contrast to simple lamellar corpuscles, glomerular nerve formations are located away the dermal papillae. In cross sections, glomerular nerve formation consists of several axonal profiles enveloped by 1-2 cytoplasmic lamellae of Schwann cells. The space among them is filled by collagenous microfibrils and the basal lamina-like material. Capsule was composed from fibroblast-like cells without definite basal lamina. An electron-dense reaction product due to non-specific cholinesterase activity was associated with Schwann cells and their processes surrounding unmyelinated terminal portion of the sensory axons. Abundant reaction product was bound to the collagenous microfibrils and was deposited in extracellular matrix between Schwann cell processes. These results are further evidence for the presence of the non-specific cholinesterase molecules as integral component of the extracellular matrix in sensory corpuscles. On the basis of histochemical study two possible explanation are considered for functional involving of this enzyme in sensory nerve formations.

Reduced risk of compressive optic neuropathy using orbital radiotherapy in patients with active thyroid eye disease.

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Shams, Pari N; Ma, Roy; Pickles, Tom; Rootman, Jack; Dolman, Peter J

2014-06-01

To compare the risk of developing compressive optic neuropathy in patients with active thyroid eye disease (TED) treated with corticosteroids with or without orbital radiotherapy. Retrospective single-center case-control study. The clinical charts of 351 patients with active TED who received corticosteroids with or without orbital radiotherapy between 1999 and 2010 were reviewed. Patients with compressive optic neuropathy at the time of presentation were excluded. Group 1 received corticosteroids only and Group 2 received corticosteroids as well as orbital radiotherapy. The primary outcome measure was the development of compressive optic neuropathy. Secondary outcome measures were changes in other parameters indicating the activity of TED, including soft tissue inflammation, diplopia, ocular motility restriction, and appearance. There were 144 cases in Group 1 and 105 in Group 2. Both groups were matched for age, sex, and stability of thyroid function. The 2 groups differed only in the modality of treatment for active TED. The main indication for treatment in both groups was soft tissue inflammation. Corticosteroids were initiated an average of 2.6 months following symptom onset in Group 1 and 2.5 months in Group 2. Group 2 received orbital radiotherapy on average 4.2 months following the initiation of corticosteroid therapy and 8% (9/105) were intolerant to corticosteroids. At an average of 3.2 years follow-up, compressive optic neuropathy had developed in 17% (25/144) of Group 1 and 0% of Group 2 (P optic neuropathy was significantly lower and improvement in ocular motility greater in patients receiving orbital radiotherapy in addition to corticosteroids. Patients with active TED appear to have an effective and sustained response to orbital radiotherapy combined with corticosteroids that is protective against disease progression and the development of compressive optic neuropathy. Copyright © 2014 Elsevier Inc. All rights reserved.

Radial nerve dysfunction

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Neuropathy - radial nerve; Radial nerve palsy; Mononeuropathy ... Damage to one nerve group, such as the radial nerve, is called mononeuropathy . Mononeuropathy means there is damage to a single nerve. Both ...

Accelerating axon growth to overcome limitations in functional recovery after peripheral nerve injury.

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Gordon, Tessa; Chan, K Ming; Sulaiman, Olawale A R; Udina, Esther; Amirjani, Nasim; Brushart, Thomas M

2009-10-01

Injured peripheral nerves regenerate at very slow rates. Therefore, proximal injury sites such as the brachial plexus still present major challenges, and the outcomes of conventional treatments remain poor. This is in part attributable to a progressive decline in the Schwann cells' ability to provide a supportive milieu for the growth cone to extend and to find the appropriate target. These challenges are compounded by the often considerable delay of regeneration across the site of nerve laceration. Recently, low-frequency electrical stimulation (as brief as an hour) has shown promise, as it significantly accelerated regeneration in animal models through speeding of axon growth across the injury site. To test whether this might be a useful clinical tool, we carried out a randomized controlled trial in patients who had experienced substantial axonal loss in the median nerve owing to severe compression in the carpal tunnel. To further elucidate the potential mechanisms, we applied rolipram, a cyclic adenosine monophosphate agonist, to rats after axotomy of the femoral nerve. We demonstrated that effects similar to those observed in animal studies could also be attained in humans. The mechanisms of action of electrical stimulation likely operate through up-regulation of neurotrophic factors and cyclic adenosine monophosphate. Indeed, the application of rolipram significantly accelerated nerve regeneration. With new mechanistic insights into the influencing factors of peripheral nerve regeneration, the novel treatments described above could form part of an armament of synergistic therapies that could make a meaningful difference to patients with peripheral nerve injuries.

Malignant peripheral nerve sheath tumor of the oculomotor nerve

DEFF Research Database (Denmark)

Kozic, D; Nagulic, M; Ostojic, J

2006-01-01

We present the short-term follow-up magnetic resonance (MR) studies and 1H-MR spectroscopy in a child with malignant peripheral nerve sheath tumor of the oculomotor nerve associated with other less aggressive cranial nerve schwannomas. The tumor revealed perineural extension and diffuse nerve...

An implantable nerve cooler for the exercising dog.

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Borgdorff, P; Versteeg, P G

1984-01-01

An implantable nerve cooler has been constructed to block cervical vago-sympathetic activity in the exercising dog reversibly. An insulated gilt brass container implanted around the nerve is perfused with cooled alcohol via silicone tubes. The flow of alcohol is controlled by an electromagnetic valve to keep nerve temperature at the required value. Nerve temperature is measured by a thermistor attached to the housing and in contact with the nerve. It is shown that, during cooling, temperature at this location differs less than 2 degrees C from nerve core temperature. Measurement of changes in heart rate revealed that complete vagal block in the conscious animal is obtained at a nerve temperature of 2 degrees C and can be achieved within 50 s. During steady-state cooling in the exercising animal nerve temperature varied less than 0.5 degree C. When the coolers after 2 weeks of implantation were removed they showed no oxydation and could be used again.

Bilateral Neuropathy of Primary Sensory Neurons by the Chronic Compression of Multiple Unilateral DRGs

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Ya-Bin Xie

2016-01-01

Full Text Available To mimic multilevel nerve root compression and intervertebral foramina stenosis in human, we established a new animal model of the chronic compression of unilateral multiple lumbar DRGs (mCCD in the rat. A higher occurrence of signs of spontaneous pain behaviors, such as wet-dog shaking and spontaneous hind paw shrinking behaviors, was firstly observed from day 1 onward. In the meantime, the unilateral mCCD rat exhibited significant bilateral hind paw mechanical and cold allodynia and hyperalgesia, as well as a thermal preference to 30°C plate between 30 and 35°C. The expression of activating transcription factor 3 (ATF3 was significantly increased in the ipsilateral and contralateral all-sized DRG neurons after the mCCD. And the expression of CGRP was significantly increased in the ipsilateral and contralateral large- and medium-sized DRG neurons. ATF3 and CGRP expressions correlated to evoked pain hypersensitivities such as mechanical and cold allodynia on postoperative day 1. The results suggested that bilateral neuropathy of primary sensory neurons might contribute to bilateral hypersensitivity in the mCCD rat.

Scaffoldless tissue-engineered nerve conduit promotes peripheral nerve regeneration and functional recovery after tibial nerve injury in rats

Institute of Scientific and Technical Information of China (English)

Aaron M. Adams; Keith W. VanDusen; Tatiana Y. Kostrominova; Jacob P. Mertens; Lisa M. Larkin

2017-01-01

Damage to peripheral nerve tissue may cause loss of function in both the nerve and the targeted muscles it innervates. This study compared the repair capability of engineered nerve conduit (ENC), engineered fibroblast conduit (EFC), and autograft in a 10-mm tibial nerve gap. ENCs were fabricated utilizing primary fibroblasts and the nerve cells of rats on embryonic day 15 (E15). EFCs were fabricated utilizing primary fi-broblasts only. Following a 12-week recovery, nerve repair was assessed by measuring contractile properties in the medial gastrocnemius muscle, distal motor nerve conduction velocity in the lateral gastrocnemius, and histology of muscle and nerve. The autografts, ENCs and EFCs reestablished 96%, 87% and 84% of native distal motor nerve conduction velocity in the lateral gastrocnemius, 100%, 44% and 44% of native specific force of medical gastrocnemius, and 63%, 61% and 67% of native medial gastrocnemius mass, re-spectively. Histology of the repaired nerve revealed large axons in the autograft, larger but fewer axons in the ENC repair, and many smaller axons in the EFC repair. Muscle histology revealed similar muscle fiber cross-sectional areas among autograft, ENC and EFC repairs. In conclusion, both ENCs and EFCs promot-ed nerve regeneration in a 10-mm tibial nerve gap repair, suggesting that the E15 rat nerve cells may not be necessary for nerve regeneration, and EFC alone can suffice for peripheral nerve injury repair.

Ulnar nerve injury due to lateral traction device during shoulder arthroscopy: Was it avoidable?

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Vivek Pandey

2017-01-01

Full Text Available Most of the nerve injuries reported during shoulder arthroscopy in a beach chair, or lateral position is related to inappropriate patient positioning or excess traction. The lateral decubitus position is more vulnerable for traction-related neuropraxia. The present case serves as an important lesson from an avoidable situation of “having a one track mind” of the surgical team during the arthroscopic repair of shoulder instability performed in the lateral decubitus position. The operating surgeon must supervise the appropriate positioning of the patient on operation table and adequate padding of vulnerable bony points before beginning of shoulder arthroscopy to prevent any position-related nerve injuries. This is probably the first case to illustrate an unusual cause of ulnar nerve compression particularly related to the use of an additional traction device in the arthroscopic repair of shoulder instability performed in lateral decubitus position, which has not been previously defined.

Communication between radial nerve and medial cutaneous nerve of forearm

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R R Marathe

2010-01-01

Full Text Available Radial nerve is usually a branch of the posterior cord of the brachial plexus. It innervates triceps, anconeous, brachialis, brachioradialis, extensor carpi radialis longus muscles and gives the posterior cutaneous nerve of the arm, lower lateral cutaneous nerve of arm, posterior cutaneous nerve of forearm; without exhibiting any communication with the medial cutaneous nerve of forearm or any other nerve. We report communication between the radial nerve and medial cutaneous nerve of forearm on the left side in a 58-year-old male cadaver. The right sided structures were found to be normal. Neurosurgeons should keep such variations in mind while performing the surgeries of axilla and upper arm.

Ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty: a multicenter randomized controlled study

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Fen Wang

2015-02-01

Full Text Available BACKGROUND AND OBJECTIVES: Postoperative analgesia is crucial for early functional excise after total knee arthroplasty. To investigate the clinical efficacy of ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty. METHODS: 46 patients with ASA grade I-III who underwent total knee arthroplasty received postoperative analgesia from October 2012 to January 2013. In 22 patients, ultrasound and nerve stimulator guided continuous femoral nerve block were performed for analgesia (CFNB group; in 24 patients, epidural analgesia was done (PCEA group. The analgesic effects, side effects, articular recovery and complications were compared between two groups. RESULTS: At 6 h and 12 h after surgery, the knee pain score (VAS score during functional tests after active exercise and after passive excise in CFNB were significantly reduced when compared with PCEA group. The amount of parecoxib used in CFNB patients was significantly reduced when compared with PCEA group. At 48 h after surgery, the muscle strength grade in CFNB group was significantly higher, and the time to ambulatory activity was shorter than those in PCEA group. The incidence of nausea and vomiting in CFNB patients was significantly reduced when compared with PCEA group. CONCLUSION: Ultrasound and nerve stimulator guided continuous femoral nerve block provide better analgesia at 6 h and 12 h, demonstrated by RVAS and PVAS. The amount of parecoxib also reduces, the incidence of nausea and vomiting decreased, the influence on muscle strength is compromised and patients can perform ambulatory activity under this condition.

Multifocal visual evoked potential in optic neuritis, ischemic optic neuropathy and compressive optic neuropathy

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Jayaraman, Manju; Gandhi, Rashmin Anilkumar; Ravi, Priya; Sen, Parveen

2014-01-01

Purpose: To investigate the effect of optic neuritis (ON), ischemic optic neuropathy (ION) and compressive optic neuropathy (CON) on multifocal visual evoked potential (mfVEP) amplitudes and latencies, and to compare the parameters among three optic nerve disorders. Materials and Methods: mfVEP was recorded for 71 eyes of controls and 48 eyes of optic nerve disorders with subgroups of optic neuritis (ON, n = 21 eyes), ischemic optic neuropathy (ION, n = 14 eyes), and compressive optic neuropathy (CON, n = 13 eyes). The size of defect in mfVEP amplitude probability plots and relative latency plots were analyzed. The pattern of the defect in amplitude probability plot was classified according to the visual field profile of optic neuritis treatment trail (ONTT). Results: Median of mfVEP amplitude (log SNR) averaged across 60 sectors were reduced in ON (0.17 (0.13-0.33)), ION (0.14 (0.12-0.21)) and CON (0.21 (0.14-0.30)) when compared to controls. The median mfVEP relative latencies compared to controls were significantly prolonged in ON and CON group of 10.53 (2.62-15.50) ms and 5.73 (2.67-14.14) ms respectively compared to ION group (2.06 (-4.09-13.02)). The common mfVEP amplitude defects observed in probability plots were diffuse pattern in ON, inferior altitudinal defect in ION and temporal hemianopia in CON eyes. Conclusions: Optic nerve disorders cause reduction in mfVEP amplitudes. The extent of delayed latency noted in ischemic optic neuropathy was significantly lesser compared to subjects with optic neuritis and compressive optic neuropathy. mfVEP amplitudes can be used to objectively assess the topography of the visual field defect. PMID:24088641

Ulnar nerve dysfunction

Science.gov (United States)

Neuropathy - ulnar nerve; Ulnar nerve palsy; Mononeuropathy; Cubital tunnel syndrome ... Damage to one nerve group, such as the ulnar nerve, is called mononeuropathy . Mononeuropathy means there is damage to a single nerve. Both ...

Optogenetic probing of nerve and muscle function after facial nerve lesion in the mouse whisker system

Science.gov (United States)

Bandi, Akhil; Vajtay, Thomas J.; Upadhyay, Aman; Yiantsos, S. Olga; Lee, Christian R.; Margolis, David J.

2018-02-01

Optogenetic modulation of neural circuits has opened new avenues into neuroscience research, allowing the control of cellular activity of genetically specified cell types. Optogenetics is still underdeveloped in the peripheral nervous system, yet there are many applications related to sensorimotor function, pain and nerve injury that would be of great benefit. We recently established a method for non-invasive, transdermal optogenetic stimulation of the facial muscles that control whisker movements in mice (Park et al., 2016, eLife, e14140)1. Here we present results comparing the effects of optogenetic stimulation of whisker movements in mice that express channelrhodopsin-2 (ChR2) selectively in either the facial motor nerve (ChAT-ChR2 mice) or muscle (Emx1-ChR2 or ACTA1-ChR2 mice). We tracked changes in nerve and muscle function before and up to 14 days after nerve transection. Optogenetic 460 nm transdermal stimulation of the distal cut nerve showed that nerve degeneration progresses rapidly over 24 hours. In contrast, the whisker movements evoked by optogenetic muscle stimulation were up-regulated after denervation, including increased maximum protraction amplitude, increased sensitivity to low-intensity stimuli, and more sustained muscle contractions (reduced adaptation). Our results indicate that peripheral optogenetic stimulation is a promising technique for probing the timecourse of functional changes of both nerve and muscle, and holds potential for restoring movement after paralysis induced by nerve damage or motoneuron degeneration.

Arthroscopic treatment of femoral nerve paresthesia caused by an acetabular paralabral cyst.

Science.gov (United States)

Kanauchi, Taira; Suganuma, Jun; Mochizuki, Ryuta; Uchikawa, Shinichi

2014-05-01

This report describes a rare case of femoral nerve paresthesia caused by an acetabular paralabral cyst of the hip joint. A 68-year-old woman presented with a 6-month history of right hip pain and paresthesia along the anterior thigh and radiating down to the anterior aspect of the knee. Radiography showed osteoarthritis with a narrowed joint space in the right hip joint. Magnetic resonance imaging showed a cyst with low T1- and high T2-weighted signal intensity arising from a labral tear at the anterior aspect of the acetabulum. The cyst was connected to the joint space and displaced the femoral nerve to the anteromedial side. The lesion was diagnosed as an acetabular paralabral cyst causing femoral neuropathy. Because the main symptom was femoral nerve paresthesia and the patient desired a less invasive procedure, arthroscopic labral repair was performed to stop synovial fluid flow to the paralabral cyst that was causing the femoral nerve paresthesia. After surgery, the cyst and femoral nerve paresthesia disappeared. At the 18-month follow-up, the patient had no recurrence. There have been several reports of neurovascular compression caused by the cyst around the hip joint. To the authors' knowledge, only 3 cases of acetabular paralabral cysts causing sciatica have been reported. The current patient appears to represent a rare case of an acetabular paralabral cyst causing femoral nerve paresthesia. The authors suggest that arthroscopic labral repair for an acetabular paralabral cyst causing neuropathy can be an option for patients who desire a less invasive procedure. Copyright 2014, SLACK Incorporated.

The Relationship amongst Intervertebral Disc Vertical Diameter, Lateral Foramen Diameter and Nerve Root Impingement in Lumbar Vertebra

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Yusof MI

2018-03-01

Full Text Available Introduction: The vertical diameter of the foramen is dependent upon the vertical diameter of the corresponding intervertebral disc. A decrease in disc vertical diameter has direct anatomic consequences to the foraminal diameter and area available for the nerve root passing through it. This study is to establish the relationship amongst the intervertebral disc vertical diameter, lateral foramen diameters and nerve root compression in the lumbar vertebra. Materials and Methods: Measurements of the study parameters were performed using sagittal MRI images. The parameters studied were: intervertebral disc vertical diameter (DVD, foraminal vertical diameter (FVD, foraminal transverse diameter (FTD and nerve root diameter (NRD of both sides. The relationship between the measured parameters were then analyzed. Results: A total of 62 MRI images were available for this study. Statistical analysis showed moderate to strong correlation between DVD and FVD at all the lumbar levels except at left L23 and L5S1 and right L3L4 and L4L5. Correlation between DVD and FTD were not significant at all lumbar levels. Regression analysis showed that a decrease of 1mm of DVD was associated with 1.3, 1.7, 3.3, 3.3 and 1.3mm reduction of FVD at L1L2, L2L3, L3L4, L4L5 and L5S1 respectively. Conclusion: Reduction of DVD was associated with reduction of FVD. However, FVD was relatively wide for the nerve root even with complete loss of DVD. FTD was much narrower than the FVD making it more likely to cause nerve root compression at the exit foramina. These anatomical details should be given consideration in treating patients with lateral canal stenosis.

The First Experience of Triple Nerve Transfer in Proximal Radial Nerve Palsy.

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Emamhadi, Mohammadreza; Andalib, Sasan

2018-01-01

Injury to distal portion of posterior cord of brachial plexus leads to palsy of radial and axillary nerves. Symptoms are usually motor deficits of the deltoid muscle; triceps brachii muscle; and extensor muscles of the wrist, thumb, and fingers. Tendon transfers, nerve grafts, and nerve transfers are options for surgical treatment of proximal radial nerve palsy to restore some motor functions. Tendon transfer is painful, requires a long immobilization, and decreases donor muscle strength; nevertheless, nerve transfer produces promising outcomes. We present a patient with proximal radial nerve palsy following a blunt injury undergoing triple nerve transfer. The patient was involved in a motorcycle accident with complete palsy of the radial and axillary nerves. After 6 months, on admission, he showed spontaneous recovery of axillary nerve palsy, but radial nerve palsy remained. We performed triple nerve transfer, fascicle of ulnar nerve to long head of the triceps branch of radial nerve, flexor digitorum superficialis branch of median nerve to extensor carpi radialis brevis branch of radial nerve, and flexor carpi radialis branch of median nerve to posterior interosseous nerve, for restoration of elbow, wrist, and finger extensions, respectively. Our experience confirmed functional elbow, wrist, and finger extensions in the patient. Triple nerve transfer restores functions of the upper limb in patients with debilitating radial nerve palsy after blunt injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

Axonal and glial currents activated during the post-tetanic hyperpolarization in non-myelinated nerve.

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Robert, A; Jirounek, P

1998-07-01

Changes in membrane potential and potassium concentration in the extracellular space ([K+]e) of rabbit vagus nerve were measured simultaneously during electrical activity and during the period of recovery using a modified sucrose-gap method and potassium-sensitive microelectrodes. After stimulation for 15 s at 15 Hz the main activity-induced increase in [K+]e reached 16.9 mM. This increase in [K+]e was paralleled by a depolarization of the preparation. The period of activity was followed by a post-tetanic hyperpolarization (PTH) lasting tens of seconds, generated by the axonal electrogenic Na+-K+ pump and to a lesser extent by the pump of the surrounding Schwann cells. The amplitude of the PTH dramatically increased in experiments in which inward currents were blocked by removal of Cl– or after application of Cs+ or Ba2+, indicating that under normal conditions the current generated by the Na+-K+ pump is strongly short-circuited. A pharmacological and kinetic study showed that these currents are: (1) the hyperpolarization-activated current I h, and (2) the inwardly rectifying I KIR current. The results show that the latter originates from Schwann cells. Our data indicate that in non-myelinated nerves there is a subtle association of inward ionic channels which (1) helps the cell to maintain an optimal membrane potential after a period of activity, and (2) contributes to the removal of excess K+ from the extracellular space.

One-stage human acellular nerve allograft reconstruction for digital nerve defects

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Xue-yuan Li

2015-01-01

Full Text Available Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of < 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After debridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6-24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction.

Nerves and nerve endings in the skin of tropical cattle.

Science.gov (United States)

Amakiri, S F; Ozoya, S E; Ogunnaike, P O

1978-01-01

The nerves and nerve endings in the skin of tropical cattle were studied using histological and histochemical techniques. Many nerve trunks and fibres were present in the reticular and papillary dermis in both hairy and non-hairy skin sites. In non-hairy skin locations such as the muzzle and lower lip, encapsulated endings akin to Krause and Ruffini end bulbs, which arise from myelinated nerve trunks situated lower down the dermis were observed at the upper papillary layer level. Some fibre trunks seen at this level extended upwards to terminate within dermal papillae as bulb-shaped longitudinally lamellated Pacinian-type endings, while other onion-shaped lamellated nerve structures were located either within dermal papillae or near the dermo-epidermal area. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. On hairy skin sites, however, organized nerve endings or intraepidermal nerve endings were not readily identifiable.

The pedunculopontine tegmentum controls renal sympathetic nerve activity and cardiorespiratory activities in nembutal-anesthetized rats.

Directory of Open Access Journals (Sweden)

Anne M Fink

Full Text Available Elevated renal sympathetic nerve activity (RSNA accompanies a variety of complex disorders, including obstructive sleep apnea, heart failure, and chronic kidney disease. Understanding pathophysiologic renal mechanisms is important for determining why hypertension is both a common sequelae and a predisposing factor of these disorders. The role of the brainstem in regulating RSNA remains incompletely understood. The pedunculopontine tegmentum (PPT is known for regulating behaviors including alertness, locomotion, and rapid eye movement sleep. Activation of PPT neurons in anesthetized rats was previously found to increase splanchnic sympathetic nerve activity and blood pressure, in addition to altering breathing. The present study is the first investigation of the PPT and its potential role in regulating RSNA. Microinjections of DL-homocysteic acid (DLH were used to probe the PPT in 100-μm increments in Nembutal-anesthetized rats to identify effective sites, defined as locations where changes in RSNA could be evoked. A total of 239 DLH microinjections were made in 18 rats, which identified 20 effective sites (each confirmed by the ability to evoke a repeatable sympathoexcitatory response. Peak increases in RSNA occurred within 10-20 seconds of PPT activation, with RSNA increasing by 104.5 ± 68.4% (mean ± standard deviation from baseline. Mean arterial pressure remained significantly elevated for 30 seconds, increasing from 101.6 ± 18.6 mmHg to 135.9 ± 36.4 mmHg. DLH microinjections also increased respiratory rate and minute ventilation. The effective sites were found throughout the rostal-caudal extent of the PPT with most located in the dorsal regions of the nucleus. The majority of PPT locations tested with DLH microinjections did not alter RSNA (179 sites, suggesting that the neurons that confer renal sympathoexcitatory functions comprise a small component of the PPT. The study also underscores the importance of further investigation to

Diagnostic nerve ultrasonography

International Nuclear Information System (INIS)

Baeumer, T.; Grimm, A.; Schelle, T.

2017-01-01

For the diagnostics of nerve lesions an imaging method is necessary to visualize peripheral nerves and their surrounding structures for an etiological classification. Clinical neurological and electrophysiological investigations provide functional information about nerve lesions. The information provided by a standard magnetic resonance imaging (MRI) examination is inadequate for peripheral nerve diagnostics; however, MRI neurography is suitable but on the other hand a resource and time-consuming method. Using ultrasonography for peripheral nerve diagnostics. With ultrasonography reliable diagnostics of entrapment neuropathies and traumatic nerve lesions are possible. The use of ultrasonography for neuropathies shows that a differentiation between different forms is possible. Nerve ultrasonography is an established diagnostic tool. In addition to the clinical examination and clinical electrophysiology, structural information can be obtained, which results in a clear improvement in the diagnostics. Ultrasonography has become an integral part of the diagnostic work-up of peripheral nerve lesions in neurophysiological departments. Nerve ultrasonography is recommended for the diagnostic work-up of peripheral nerve lesions in addition to clinical and electrophysiological investigations. It should be used in the clinical work-up of entrapment neuropathies, traumatic nerve lesions and spacy-occupying lesions of nerves. (orig.) [de

Nerve ultrasound shows subclinical peripheral nerve involvement in neurofibromatosis type 2.

Science.gov (United States)

Telleman, Johan A; Stellingwerff, Menno D; Brekelmans, Geert J; Visser, Leo H

2018-02-01

Neurofibromatosis type 2 (NF2) is mainly associated with central nervous system (CNS) tumors. Peripheral nerve involvement is described in symptomatic patients, but evidence of subclinical peripheral nerve involvement is scarce. We conducted a cross-sectional pilot study in 2 asymptomatic and 3 minimally symptomatic patients with NF2 to detect subclinical peripheral nerve involvement. Patients underwent clinical examination, nerve conduction studies (NCS), and high-resolution ultrasonography (HRUS). A total of 30 schwannomas were found, divided over 20 nerve segments (33.9% of all investigated nerve segments). All patients had at least 1 schwannoma. Schwannomas were identified with HRUS in 37% of clinically unaffected nerve segments and 50% of nerve segments with normal NCS findings. HRUS shows frequent subclinical peripheral nerve involvement in NF2. Clinicians should consider peripheral nerve involvement as a cause of weakness and sensory loss in the extremities in patients with this disease. Muscle Nerve 57: 312-316, 2018. © 2017 Wiley Periodicals, Inc.

Post-evaluation of the neurophaties treatment post-trauma with therapeutic laser. Model in sciatic nerve of frog

International Nuclear Information System (INIS)

Escobar, Antonio S.; Ocampo, Arcelia F. M.; Hernandez, Maria G. H.; Jasso, Jose L. C.; Lira, Maricela O. F.; Flores, Mariana A.; Balderrama, Vicente L.

2010-01-01

The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% formalin. The latency recorded by stimulating the sciatic nerve of frog to 0.5 mA and 100 ms in groups 1 and 2 show significant differences (p 000), as to the extent, if any statistically significant difference. (p<0.001 and p<0.000). The laser produces a favorable response in the treatment of paresthesia (post-traumatic neuropathy).

Consequences of Laughter Upon Trunk Compression and Cortical Activation: Linear and Polynomial Relations

Science.gov (United States)

Svebak, Sven

2016-01-01

Results from two studies of biological consequences of laughter are reported. A proposed inhibitory brain mechanism was tested in Study 1. It aims to protect against trunk compression that can cause health hazards during vigorous laughter. Compression may be maximal during moderate durations and, for protective reasons, moderate in enduring vigorous laughs. Twenty-five university students volunteered to see a candid camera film. Laughter responses (LR) and the superimposed ha-responses were operationally assessed by mercury-filled strain gauges strapped around the trunk. On average, the thorax compression amplitudes exceeded those of the abdomen, and greater amplitudes were seen in the males than in the females after correction for resting trunk circumference. Regression analyses supported polynomial relations because medium LR durations were associated with particularly high thorax amplitudes. In Study 2, power changes were computed in the beta and alpha EEG frequency bands of the parietal cortex from before to after exposure to the comedy “Dinner for one” in 56 university students. Highly significant linear relations were calculated between the number of laughs and post-exposure cortical activation (increase of beta, decrease of alpha) due to high activation after frequent laughter. The results from Study 1 supported the hypothesis of a protective brain mechanism that is activated during long LRs to reduce the risk of harm to vital organs in the trunk cavity. The results in Study 2 supported a linear cortical activation and, thus, provided evidence for a biological correlate to the subjective experience of mental refreshment after laughter. PMID:27547260

ALKALI-ACTIVATION KINETICS OF PHOSPHORUS SLAG CEMENT USING COMPRESSIVE STRENGTH DATA

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Hojjatollah Maghsoodloorad

2015-09-01

Full Text Available In this research, through compressive strength data, the order and kinetics of alkali-activation of phosphorus slag activated with two compound activators of NaOH + Na2CO3 and Na2CO3 + Ca(OH2, has been evaluated. The kinetics and order of alkali activation is a key factor to forecasting the mechanical behavior of alkali activated cement at different curing time and temperatures without carrying out experimental tests. The apparent activation energy was obtained as 35.6 kJ.mol-1 and 60.7 kJ.mol-1 for the two activators, respectively. Investigations proved that the alkali-activation kinetics of phosphorus slag resembles chemical reactions of second order. Moreover, the order of alkali-activation of phosphorus slag does not depend on the type of activator.

Polymeric Nerve Conduits with Contact Guidance Cues Used in Nerve Repair

Institute of Scientific and Technical Information of China (English)

G DAI; X NIU; J YIN

2016-01-01

In the modern life, the nerve injury frequently happens due to mechanical, chemical or thermal accidents. In the trivial injuries, the peripheral nerves can regenerate on their own; however, in most of the cases the clinical treatments are required, where relatively large nerve injury gaps are formed. Currently, the nerve repair can be accomplished by direct suture when the injury gap is not too large;while the autologous nerve graft working as the gold standard of peripheral nerve injury treatment for nerve injuries with larger gaps. However, the direct suture is limited by heavy tension at the suture sites, and the autologous nerve graft also has the drawbacks of donor site morbidity and insufifcient donor tissue. Recently, artiifcial nerve conduits have been developed as an alternative for clinical nerve repair to overcome the limitations associated with the above treatments. In order to further improve the efifciency of nerve conduits, various guidance cues are incorporated, including physical cues, biochemical signals, as well as support cells. First, this paper reviewed the contact guidance cues applied in nerve conduits, such as lumen ifllers, multi-channels and micro-patterns on the inner surface. Then, the paper focused on the polymeric nerve conduits with micro inner grooves. The polymeric nerve conduits were fabricated using the phase inversion-based ifber spinning techniques. The smart spinneret with grooved die was designed in the spinning platform, while different spinning conditions, including flow rates, air-gap distances, and polymer concentrations, were adjusted to investigate the inlfuence of fabrication conditions on the geometry of nerve conduits. The inner groove size in the nerve conduits can be precisely controlled in our hollow ifber spinning process, which can work as the efifcient contact guidance cue for nerve regeneration.

Mobilização do osso pisiforme no tratamento da neuropraxia do nervo ulnar no canal de Guyon: relato de caso Pisiform bone mobilization for treating ulnar nerve neuropraxia at Guyon's canal: case report

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Júlio Guilherme Silva

2009-12-01

Full Text Available As neuropraxias do nervo ulnar são lesões bastante freqüentes que provocam efeitos deletérios, como diminuição de força muscular e parestesias; geralmente ocorrem no nível do epicôndilo medial e do túnel ulnar (canal de Guyon. São escassos os relatos referentes a técnicas de terapia manual para compressões do nervo ulnar no canal de Guyon. Este trabalho relata o uso da técnica de mobilização do pisiforme na compressão do nervo ulnar no canal de Guyon de um homem que sofreu luxação do punho direito aos 8 anos e, aos 25, queixava-se de um deficit para adução do dedo mínimo, que atrapalhava a realização de algumas atividades de vida diária. O paciente foi submetido a uma única sessão de mobilização articular do pisiforme. Após a aplicação da técnica, o sinal positivo do teste foi eliminado, restabelecendo-se a função de adução do 5o dedo. Embora carecendo de maior fundamentação teórica, pode-se afirmar que a técnica usada, de mobilização articular do osso pisiforme, é eficaz para melhora do quadro de paresia por neuropraxia do nervo ulnar no canal de Guyon.A common ulnar nerve neuropraxia is lesion that may result in muscle strength decrease and/or paresthesia; it usually takes place at medial epicondyle level and the ulnar tunnel (Guyon's canal. Studies on manual therapy techniques for ulnar nerve compression in Guyon's canal are scarce. This paper reports the use of a technique of pisiform bone mobilization for relieving ulnar nerve compression in Guyon's canal, in a man who had suffered a luxation of the right wrist at the age of 8 and, at 25, complained of adduction deficit of the fifth finger that interfered in his daily life activities. He was submitted to one session of pisiform mobilization; after the session, the positive test sign was eliminated, thus restoring the fifth finger function. Though lacking further grounding, it may be said that the technique used, of mobilizing the pisiform bone

Compressive neuropathy of the first branch of the lateral plantar nerve: a study by magnetic resonance imaging

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Rogéria Nobre Rodrigues

2015-12-01

Full Text Available Abstract Objective: To assess the prevalence of isolated findings of abnormalities leading to entrapment of the lateral plantar nerve and respective branches in patients complaining of chronic heel pain, whose magnetic resonance imaging exams have showed complete selective fatty atrophy of the abductor digiti quinti muscle. Materials and Methods: Retrospective, analytical, and cross-sectional study. The authors selected magnetic resonance imaging of hindfoot of 90 patients with grade IV abductor digiti quinti muscle atrophy according to Goutallier and Bernageau classification. Patients presenting with minor degrees of fatty muscle degeneration (below grade IV and those who had been operated on for nerve decompression were excluded. Results: A female prevalence (78.8% was observed, and a strong correlation was found between fatty muscle atrophy and plantar fasciitis in 21.2%, and ankle varices, in 16.8% of the patients. Conclusion: Fatty atrophy of the abductor digiti quinti muscle is strongly associated with neuropathic alterations of the first branch of the lateral plantar nerve. The present study showed a significant association between plantar fasciitis and ankle varices with grade IV atrophy of the abductor digiti quinti muscle.

Tissue-engineered spiral nerve guidance conduit for peripheral nerve regeneration.

Science.gov (United States)

Chang, Wei; Shah, Munish B; Lee, Paul; Yu, Xiaojun

2018-06-01

Recently in peripheral nerve regeneration, preclinical studies have shown that the use of nerve guidance conduits (NGCs) with multiple longitudinally channels and intra-luminal topography enhance the functional outcomes when bridging a nerve gap caused by traumatic injury. These features not only provide guidance cues for regenerating nerve, but also become the essential approaches for developing a novel NGC. In this study, a novel spiral NGC with aligned nanofibers and wrapped with an outer nanofibrous tube was first developed and investigated. Using the common rat sciatic 10-mm nerve defect model, the in vivo study showed that a novel spiral NGC (with and without inner nanofibers) increased the successful rate of nerve regeneration after 6 weeks recovery. Substantial improvements in nerve regeneration were achieved by combining the spiral NGC with inner nanofibers and outer nanofibrous tube, based on the results of walking track analysis, electrophysiology, nerve histological assessment, and gastrocnemius muscle measurement. This demonstrated that the novel spiral NGC with inner aligned nanofibers and wrapped with an outer nanofibrous tube provided a better environment for peripheral nerve regeneration than standard tubular NGCs. Results from this study will benefit for future NGC design to optimize tissue-engineering strategies for peripheral nerve regeneration. We developed a novel spiral nerve guidance conduit (NGC) with coated aligned nanofibers. The spiral structure increases surface area by 4.5 fold relative to a tubular NGC. Furthermore, the aligned nanofibers was coated on the spiral walls, providing cues for guiding neurite extension. Finally, the outside of spiral NGC was wrapped with randomly nanofibers to enhance mechanical strength that can stabilize the spiral NGC. Our nerve histological data have shown that the spiral NGC had 50% more myelinated axons than a tubular structure for nerve regeneration across a 10 mm gap in a rat sciatic nerve

Peripheral Nerve Dysfunction in Middle-Aged Subjects Born with Thalidomide Embryopathy.

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Alessia Nicotra

Full Text Available Phocomelia is an extremely rare congenital malformation that emerged as one extreme of a range of defects resulting from in utero exposure to thalidomide. Individuals with thalidomide embryopathy (TE have reported developing symptoms suggestive of peripheral nervous system dysfunction in the mal-developed limbs in later life.Case control study comparing TE subjects with upper limb anomalies and neuropathic symptoms with healthy controls using standard neurophysiological testing. Other causes of a peripheral neuropathy were excluded prior to assessment.Clinical examination of 17 subjects with TE (aged 50.4±1.3 [mean±standard deviation] years, 10 females and 17 controls (37.9±9.0 years; 8 females demonstrated features of upper limb compressive neuropathy in three-quarters of subjects. Additionally there were examination findings suggestive of mild sensory neuropathy in the lower limbs (n = 1, L5 radiculopathic sensory impairment (n = 1 and cervical myelopathy (n = 1. In TE there were electrophysiological changes consistent with a median large fibre neuropathic abnormality (mean compound muscle action potential difference -6.3 mV ([-9.3, -3.3], p = 0.0002 ([95% CI], p-value and reduced sympathetic skin response amplitudes (-0.8 mV ([-1.5, -0.2], p = 0.0089 in the affected upper limbs. In the lower limbs there was evidence of sural nerve dysfunction (sensory nerve action potential -5.8 μV ([-10.7, -0.8], p = 0.0232 and impaired warm perception thresholds (+3.0°C ([0.6, 5.4], p = 0.0169.We found a range of clinical features relevant to individuals with TE beyond upper limb compressive neuropathies supporting the need for a detailed neurological examination to exclude other treatable pathologies. The electrophysiological evidence of large and small fibre axonal nerve dysfunction in symptomatic and asymptomatic limbs may be a result of the original insult and merits further investigation.

Hip adductor activations during run-to-cut manoeuvres in compression shorts: implications for return to sport after groin injury.

Science.gov (United States)

Chaudhari, Ajit M W; Jamison, Steven T; McNally, Michael P; Pan, Xueliang; Schmitt, Laura C

2014-01-01

Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention of or recovery from hip adductor strains. Large, eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography (EMG) of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut manoeuvres in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all P < 0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts.

Comparison of exertion required to perform standard and active compression-decompression cardiopulmonary resuscitation.

Science.gov (United States)

Shultz, J J; Mianulli, M J; Gisch, T M; Coffeen, P R; Haidet, G C; Lurie, K G

1995-02-01

Active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) utilizes a hand-held suction device with a pressure gauge that enables the operator to compress as well as actively decompress the chest. This new CPR method improves hemodynamic and ventilatory parameters when compared with standard CPR. ACD-CPR is easy to perform but may be more labor intensive. The purpose of this study was to quantify and compare the work required to perform ACD and standard CPR. Cardiopulmonary testing was performed on six basic cardiac life support- and ACD-trained St. Paul, MN fire-fighter personnel during performance of 10 min each of ACD and standard CPR on a mannequin equipped with a compression gauge. The order of CPR techniques was determined randomly with > 1 h between each study. Each CPR method was performed at 80 compressions/min (timed with a metronome), to a depth of 1.5-2 inches, and with a 50% duty cycle. Baseline cardiopulmonary measurements were similar at rest prior to performance of both CPR methods. During standard and ACD-CPR, respectively, rate-pressure product was 18.2 +/- 3.0 vs. 23.8 +/- 1.7 (x 1000, P CPR compared with standard CPR. Both methods require subanaerobic energy expenditure and can therefore be sustained for a sufficient length of time by most individuals to optimize resuscitation efforts. Due to the slightly higher work requirement, ACD-CPR may be more difficult to perform compared with standard CPR for long periods of time, particularly by individuals unaccustomed to the workload requirement of CPR, in general.

Sensation, mechanoreceptor, and nerve fiber function after nerve regeneration

DEFF Research Database (Denmark)

Krarup, Christian; Rosén, Birgitta; Boeckstyns, Michel

2017-01-01

Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis, and mechanoreceptor and sensory fiber...... function after nerve regeneration. Methods: Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique, including tactile stimulation of mechanoreceptors, were followed for 2...... years, and results were compared to noninjured hands. Results: At both repair methods, touch thresholds at the finger tips recovered to 81 ± 3% and tactile gnosis only to 20 ± 4% (p nerve action potentials (SNAPs) remained dispersed and areas recovered to 23 ± 2...

The role of great auricular-facial nerve neurorrhaphy in facial nerve damage

OpenAIRE

Sun, Yan; Liu, Limei; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo

2015-01-01

Background: Facial nerve is easy to be damaged, and there are many reconstructive methods for facial nerve reconstructive, such as facial nerve end to end anastomosis, the great auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. However, there is still little study about great auricular-facial nerve neurorrhaphy. The aim of the present study was to identify the role of great auricular-facial nerve neurorrhaphy and the mechanism. Methods: Rat models of facia...

Neurapraxia of the common peroneal nerve - A rare complication resulting from wearing a KBM prosthesis: A case report

NARCIS (Netherlands)

Reinders, M.F.; Geertzen, J.H.B.; Rietman, J.S.

1996-01-01

This clinical note describes a 47-year-old man who had a traumatic amputation of the left lower leg. Two months after wearing a Kondylen Bettung Munster (KMB) prosthesis, he developed a compression neuropathy of the common peroneal nerve of his right leg after sitting cross-legged. This troublesome

DNABIT Compress - Genome compression algorithm.

Science.gov (United States)

Rajarajeswari, Pothuraju; Apparao, Allam

2011-01-22

Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, "DNABIT Compress" for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that "DNABIT Compress" algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases.

The role of great auricular-facial nerve neurorrhaphy in facial nerve damage.

Science.gov (United States)

Sun, Yan; Liu, Limei; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo

2015-01-01

Facial nerve is easy to be damaged, and there are many reconstructive methods for facial nerve reconstructive, such as facial nerve end to end anastomosis, the great auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. However, there is still little study about great auricular-facial nerve neurorrhaphy. The aim of the present study was to identify the role of great auricular-facial nerve neurorrhaphy and the mechanism. Rat models of facial nerve cut (FC), facial nerve end to end anastomosis (FF), facial-great auricular neurorrhaphy (FG), and control (Ctrl) were established. Apex nasi amesiality observation, electrophysiology and immunofluorescence assays were employed to investigate the function and mechanism. In apex nasi amesiality observation, it was found apex nasi amesiality of FG group was partly recovered. Additionally, electrophysiology and immunofluorescence assays revealed that facial-great auricular neurorrhaphy could transfer nerve impulse and express AChR which was better than facial nerve cut and worse than facial nerve end to end anastomosis. The present study indicated that great auricular-facial nerve neurorrhaphy is a substantial solution for facial lesion repair, as it is efficiently preventing facial muscles atrophy by generating neurotransmitter like ACh.

Pinched Nerve

Science.gov (United States)

... You are here Home » Disorders » All Disorders Pinched Nerve Information Page Pinched Nerve Information Page What research is being done? Within the NINDS research programs, pinched nerves are addressed primarily through studies associated with pain ...

Dexamethasone minimizes the risk of cranial nerve injury during CEA.

Science.gov (United States)

Regina, Guido; Angiletta, Domenico; Impedovo, Giovanni; De Robertis, Giovanni; Fiorella, Marialuisa; Carratu', Maria Rosaria

2009-01-01

The incidence of cranial and cervical nerve injury during carotid endarterectomy (CEA) ranges from less than 7.6% to more than 50%. Lesions are mainly due to surgical maneuvers such as traction, compression, tissue electrocoagulation, clamping, and extensive dissections. The use of dexamethasone (DEX) and its beneficial effects in spinal cord injuries have already been described. We investigated whether DEX could also be beneficial to minimize the incidence of cranial and cervical nerve injury during CEA. To evaluate whether dexamethasone is able to reduce the incidence of cranial nerve injuries. From March 1999 through April 2006, 1126 patients undergoing CEA because of high-grade carotid stenosis were enrolled and randomized by predetermined randomization tables into two groups. The first group, "A", included 586 patients that all received an intravenous administration of dexamethasone following a therapeutic scheme. The second group, "B", included 540 control subjects that received the standard pre- and postoperative therapy. All patients were submitted to a deep cervical plexus block, eversion carotid endarterectomy, and selective shunting. Three days after the operation, an independent neurologist and otorhinolaryngologist evaluated the presence of cranial nerve deficits. All patients (group A and group B) showing nerve injuries continued the treatment (8 mg of dexamethasone once in the morning) for 7 days and were re-evaluated after 2 weeks, 30 days, and every 3 months for 1 year. Recovery time took from 2 weeks to 12 months, with a mean time of 3.6 months. The chi(2) test was used to compare the two groups and to check for statistical significance. The incidence of cranial nerve dysfunction was higher in group B and the statistical analysis showed a significant effect of dexamethasone in preventing the neurological damage (P = .0081). The incidence of temporary lesions was lower in group A and the chi(2) test yielded a P value of .006. No statistically

Assessment of nerve regeneration across nerve allografts treated with tacrolimus.

Science.gov (United States)

Haisheng, Han; Songjie, Zuo; Xin, Li

2008-01-01

Although regeneration of nerve allotransplant is a major concern in the clinic, there have been few papers quantitatively assessing functional recovery of animals' nerve allografts in the long term. In this study, functional recovery, histopathological study, and immunohistochemistry changes of rat nerve allograft with FK506 were investigated up to 12 weeks without slaughtering. C57 and SD rats were used for transplantation. The donor's nerve was sliced and transplanted into the recipient. The sciatic nerve was epineurally sutured with 10-0 nylon. In total, 30 models of transplantation were performed and divided into 3 groups that were either treated with FK506 or not. Functional recovery of the grafted nerve was serially assessed by the pin click test, walking track analysis and electrophysiological evaluations. A histopathological study and immunohistochemistry study were done in the all of the models. Nerve allografts treated with FK506 have no immune rejection through 12 weeks. Sensibility had similarly improved in both isografts and allografts. There has been no difference in each graft. Walk track analysis demonstrates significant recovery of motor function of the nerve graft. No histological results of difference were found up to 12 weeks in each graft. In the rodent nerve graft model, FK506 prevented nerve allograft rejection across a major histocompatibility barrier. Sensory recovery seems to be superior to motor function. Nerve isograft and allograft treated with FK506 have no significant difference in function recovery, histopathological result, and immunohistochemistry changes.

Isolated oculomotor nerve palsy resulting from acute traumatic tentorial subdural hematoma

Directory of Open Access Journals (Sweden)

Cui V

2016-10-01

Full Text Available Victoria Cui,1 Timur Kouliev2 1Washington University School of Medicine, St Louis, MO, USA; 2Emergency Department, Beijing United Family Hospital, Beijing, China Abstract: Acute subdural hematoma (SDH resulting from head trauma is a potentially life-threatening condition that requires expedient diagnosis and intervention to ensure optimal patient outcomes. Rapidly expanding or large hematomas, elevated intracranial pressure, and associated complications of brain herniation are associated with high mortality rates and poor recovery of neurological function. However, smaller bleeds (clot thickness <10 mm or hematomas occurring in infrequent locations, such as the tentorium cerebelli, may be difficult to recognize and patients may present with unusual or subtle signs and symptoms, including isolated cranial nerve palsies. Knowledge of neuroanatomy supported by modern neuroimaging can greatly aid in recognition and diagnosis of such lesions. In this report, we present a case of isolated oculomotor nerve palsy resulting from compressive tentorial SDH following blunt head trauma, review the literature concerning similar cases, and make recommendations regarding the diagnosis of SDH in patients presenting with isolated cranial nerve palsies. Keywords: head injury, oculomotor, palsy, subdural hematoma, trauma, tentorium, cerebral herniation, intracranial hemorrhage

Somatic modulation of spinal reflex bladder activity mediated by nociceptive bladder afferent nerve fibers in cats.

Science.gov (United States)

Xiao, Zhiying; Rogers, Marc J; Shen, Bing; Wang, Jicheng; Schwen, Zeyad; Roppolo, James R; de Groat, William C; Tai, Changfeng

2014-09-15

The goal of the present study was to determine if supraspinal pathways are necessary for inhibition of bladder reflex activity induced by activation of somatic afferents in the pudendal or tibial nerve. Cats anesthetized with α-chloralose were studied after acute spinal cord transection at the thoracic T9/T10 level. Dilute (0.25%) acetic acid was used to irritate the bladder, activate nociceptive afferent C-fibers, and trigger spinal reflex bladder contractions (amplitude: 19.3 ± 2.9 cmH2O). Hexamethonium (a ganglionic blocker, intravenously) significantly (P reflex bladder contractions to 8.5 ± 1.9 cmH2O. Injection of lidocaine (2%, 1-2 ml) into the sacral spinal cord or transection of the sacral spinal roots and spinal cord further reduced the contraction amplitude to 4.2 ± 1.3 cmH2O. Pudendal nerve stimulation (PNS) at frequencies of 0.5-5 Hz and 40 Hz but not at 10-20 Hz inhibited reflex bladder contractions, whereas tibial nerve stimulation (TNS) failed to inhibit bladder contractions at all tested frequencies (0.5-40 Hz). These results indicate that PNS inhibition of nociceptive afferent C-fiber-mediated spinal reflex bladder contractions can occur at the spinal level in the absence of supraspinal pathways, but TNS inhibition requires supraspinal pathways. In addition, this study shows, for the first time, that after acute spinal cord transection reflex bladder contractions can be triggered by activating nociceptive bladder afferent C-fibers using acetic acid irritation. Understanding the sites of action for PNS or TNS inhibition is important for the clinical application of pudendal or tibial neuromodulation to treat bladder dysfunctions. Copyright © 2014 the American Physiological Society.

Manual therapy and neurodynamic mobilization in a patient with peroneal nerve paralysis: a case report.

Science.gov (United States)

Villafañe, Jorge Hugo; Pillastrini, Paolo; Borboni, Alberto

2013-09-01

The purpose of this case report is to describe a therapeutic intervention for peroneal nerve paralysis involving the sciatic nerve. A 24-year-old man presented with peroneal nerve paralysis with decreased sensation, severe pain in the popliteal fossa, and steppage gait, which occurred 3 days prior to the consultation. Magnetic resonance imaging and electromyography confirmed lumbar disk herniation with sciatic common peroneal nerve entrapment in the popliteal fossa. A combined treatment protocol of spinal and fibular head manipulation and neurodynamic mobilization including soft tissue work of the psoas and hamstring muscles was performed. Outcome measures were assessed at pretreatment, 1 week posttreatment, and 3-month follow-up and included numeric pain rating scale, range of motion, pressure pain threshold, and manual muscle testing. Treatment interventions were applied for 3 sessions over a period of 1 week. Results showed reduction of the patient's subjective pain and considerable improvement in range of motion, strength, and sensation in his left foot, which was restored to full function. A combined program of spinal and fibular head manipulation and neurodynamic mobilization reduced pain, increased range of motion and strength, and restored full function to the left leg in this patient who had severe functional impairment related to a compressed left common peroneal nerve.

Peripheral nerve regeneration through P(DLLA-epsilon-CL) nerve guides

NARCIS (Netherlands)

Den Dunnen, WFA; Meek, MF; Robinson, PH; Schakernraad, JM

1998-01-01

P(DLLA-epsilon-CL) nerve guides can be used perfectly for short nerve gaps in rats, and are even better than short autologous nerve grafts. The tube dimensions, such as the internal diameter and wall thickness, are very important for the final outcome of peripheral nerve regeneration, as well as the

Characterizing biological variability in livestock blood cholinesterase activity for biomonitoring organophosphate nerve agent exposure

Energy Technology Data Exchange (ETDEWEB)

Halbrook, R.S.; Shugart, L.R.; Watson, A.P.; Munro, N.B.; Linnabary, R.D. (Environmental Sciences Division, Oak Ridge National Laboratory, TN (United States))

1992-09-01

A biomonitoring protocol, using blood cholinesterase (ChE) activity in livestock as a monitor of potential organophosphate nerve agent exposure during the planned destruction of US unitary chemical warfare agent stockpiles, is described. The experimental design included analysis of blood ChE activity in individual healthy sheep, horses, and dairy and beef cattle during a 10- to 12-month period. Castrated and sexually intact males, pregnant and lactating females, and adult and immature animals were examined through at least one reproductive cycle. The same animals were used throughout the period of observation and were not exposed to ChE-inhibiting organophosphate or carbamate compounds. A framework for an effective biomonitoring protocol within a monitoring area includes establishing individual baseline blood ChE activity for a sentinel group of 6 animals on the bases of blood samples collected over a 6-month period, monthly collection of blood samples for ChE-activity determination during monitoring, and selection of adult animals as sentinels. Exposure to ChE-inhibiting compounds would be suspected when all blood ChE activity of all animals within the sentinel group are decreased greater than 20% from their own baseline value. Sentinel species selection is primarily a logistical and operational concern; however, sheep appear to be the species of choice because within-individual baseline ChE activity and among age and gender group ChE activity in sheep had the least variability, compared with data from other species. This protocol provides an effective and efficient means for detecting abnormal depressions in blood ChE activity in livestock and can serve as a valuable indicator of the extent of actual plume movement and/or deposition in the event of organophosphate nerve agent release.

[Positional damage of the sciatic nerve during neurosurgical intervention into the posterior cranial fossa in the sitting position].

Science.gov (United States)

Konovalov, A N; Lubnin, A Iu; Shimanskiĭ, V N; Kolycheva, M V; Ogurtsova, A A; Grigorian, A A

2009-01-01

The paper describes a rare case of severe, but reversible bilateral damage to the sciatic nerve (compression neuropathy) in a patient with Blumenbach's clivus meningioma developing during 12-hour operation removing the tumor in the patient's sitting position on the operating table. The etiology and prevention of this complication are discussed.

Distal nerve transfer versus supraclavicular nerve grafting: comparison of elbow flexion outcome in neonatal brachial plexus palsy with C5-C7 involvement.

Science.gov (United States)

Heise, Carlos O; Siqueira, Mario G; Martins, Roberto S; Foroni, Luciano H; Sterman-Neto, Hugo

2017-09-01

Ulnar and median nerve transfers to arm muscles have been used to recover elbow flexion in infants with neonatal brachial plexus palsy, but there is no direct outcome comparison with the classical supraclavicular nerve grafting approach. We retrospectively analyzed patients with C5-C7 neonatal brachial plexus palsy submitted to nerve surgery and recorded elbow flexion recovery using the active movement scale (0-7) at 12 and 24 months after surgery. We compared 13 patients submitted to supraclavicular nerve grafting with 21 patients submitted to distal ulnar or median nerve transfer to biceps motor branch. We considered elbow flexion scores of 6 or 7 as good results. The mean elbow flexion score and the proportion of good results were better using distal nerve transfers than supraclavicular grafting at 12 months (p nerve grafting at 12 months showed good elbow flexion recovery after ulnar nerve transfers. Distal nerve transfers provided faster elbow flexion recovery than supraclavicular nerve grafting, but there was no significant difference in the outcome after 24 months of surgery. Patients with failed supraclavicular grafting operated early can still benefit from late distal nerve transfers. Supraclavicular nerve grafting should remain as the first line surgical treatment for children with neonatal brachial plexus palsy.

Cranial nerve monitoring during subpial dissection in temporomesial surgery.

Science.gov (United States)

Ortler, Martin; Fiegele, Thomas; Walser, Gerald; Trinka, Eugen; Eisner, Wilhelm

2011-06-01

Cranial nerves (CNs) crossing between the brainstem and skull base at the level of the tentorial hiatus may be at risk in temporomesial surgery involving subpial dissection and/or tumorous growth leading to distorted anatomy. We aimed to identify the surgical steps most likely to result in CN damage in this type of surgery. Electromyographic responses obtained with standard neuromonitoring techniques and a continuous free-running EMG were graded as either contact activity or pathological spontaneous activity (PSA) during subpial resection of temporomesial structures in 16 selective amygdalohippocampectomy cases. Integrity of peripheral motor axons was tested by transpial/transarachnoidal electrical stimulation while recording compound muscle action potentials from distal muscle(s). Continuous EMG showed pathological activity in five (31.2%) patients. Nine events with PSA (slight activity, n = 8; strong temporary activity, n = 1) were recorded. The oculomotor nerve was involved three times, the trochlear nerve twice, the facial nerve once, and all monitored nerves on three occasions. Surgical maneuvers associated with PSA were the resection of deep parts of the hippocampus and parahippocampal gyrus (CN IV, twice; CN III, once), lining with or removing cotton patties from the resection cavity (III, twice; all channels, once) and indirect exertion of tension on the intact pia/arachnoid of the uncal region while mobilizing the hippocampus and parahippocampal gyrus en bloc (all channels, once; III, once). CMAPs were observed at 0.3 mA in two patients and at 0.6 mA in one patient, and without registering the exact amount of intensity in three patients. The most dangerous steps leading to cranial nerve damage during mesial temporal lobe surgery are the final stages of the intervention while the resection is being completed in the deep posterior part and the resection cavity is being lined with patties. Distant traction may act on nerves crossing the tentorial

A review of nerve conduction studies in cases of suspected compression neuropathies of the upper limb.

LENUS (Irish Health Repository)

Neligan, A

2010-01-01

Entrapment neuropathies, particularly those affecting upper limbs, are common reasons for referral for nerve conduction studies (NCS). However, concordance between clinical findings and NCS findings, especially in patients being considered for intervention including decompressive surgery, has not been assessed.

Lipofibromatous hamartoma of the superficial peroneal nerve: Two case reports

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Ying-Ling Kuo

2012-03-01

Full Text Available Lipofibromatous hamartoma, a rarely occurring nerve hamartoma, can present as an acrochordon, cutaneous cyst or other soft tissue tumor and is usually seen within the first three decades of life. The lesion presents as a slowly growing mass that is largely composed of fat and fibrous tissue with epineural and perineural proliferation. Although such tumors are rare, it is important for physicians to be aware of this disorder and recognize its signs because patients may present with what appears to be a benign skin tumor. If left untreated, the lesion may result in nerve compression and eventually lead to the development of peripheral neuropathy. Here, we present two cases of lipofibromatous hamartomas that presented over the ankle and dorsal foot, respectively, that appeared as simple and benign tumors upon initial inspection. Patients were without symptoms or neurological deficits, and diagnosis was not made until histopathological examination of the biopsied specimens. We also discuss the clinical manifestations, histopathological findings, and the management of lipofibromatous hamartomas.

Comparison of optic disc morphology of optic nerve atrophy between compressive optic neuropathy and glaucomatous optic neuropathy.

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Masayuki Hata

Full Text Available To compare the optic nerve head (ONH structure between compressive optic neuropathy (CON and glaucomatous optic neuropathy (GON, and to determine whether selected ONH quantitative parameters effectively discriminate between GON and CON, especially CON cases presenting with a glaucoma-like disc.We prospectively assessed 34 patients with CON, 34 age-matched patients with moderate or severe GON, and 34 age-matched healthy control subjects. The quantitative parameters of ONH structure were compared using the Heidelberg Retina Tomograph 2 (HRT2 and Spectralis optical coherence tomography with an enhanced depth imaging method.The mean and maximum cup depths of CON were significantly smaller than those with GON (P < 0.001 and P < 0.001, respectively. The distance between Bruch's membrane opening and anterior surface of the lamina cribrosa (BMO-anterior LC of CON was also significantly smaller than that of glaucoma but was similar to that of the healthy group (P < 0.001 and P = 0.47, respectively. Based on Moorfields regression analysis of the glaucoma classification of HRT2, 15 eyes with CON were classified with a glaucoma-like disc. The cup/disc area ratio did not differ between cases of CON with a glaucoma-like disc and cases of GON (P = 0.16, but the BMO-anterior LC and mean and maximum cup depths of CON cases with a glaucoma-like disc were smaller than those in GON (P = 0.005, P = 0.003, and P = 0.001, respectively.Measurements of the cup depths and the LC depth had good ability to differentiate between CON with a glaucoma-like disc and glaucoma. There was no laminar remodeling detected by laminar surface position in the patients with CON compared to those with GON.

Hydrogel derived from porcine decellularized nerve tissue as a promising biomaterial for repairing peripheral nerve defects.

Science.gov (United States)

Lin, Tao; Liu, Sheng; Chen, Shihao; Qiu, Shuai; Rao, Zilong; Liu, Jianghui; Zhu, Shuang; Yan, Liwei; Mao, Haiquan; Zhu, Qingtang; Quan, Daping; Liu, Xiaolin

2018-06-01

Decellularized matrix hydrogels derived from tissues or organs have been used for tissue repair due to their biocompatibility, tunability, and tissue-specific extracellular matrix (ECM) components. However, the preparation of decellularized peripheral nerve matrix hydrogels and their use to repair nerve defects have not been reported. Here, we developed a hydrogel from porcine decellularized nerve matrix (pDNM-G), which was confirmed to have minimal DNA content and retain collagen and glycosaminoglycans content, thereby allowing gelatinization. The pDNM-G exhibited a nanofibrous structure similar to that of natural ECM, and a ∼280-Pa storage modulus at 10 mg/mL similar to that of native neural tissues. Western blot and liquid chromatography tandem mass spectrometry analysis revealed that the pDNM-G consisted mostly of ECM proteins and contained primary ECM-related proteins, including fibronectin and collagen I and IV). In vitro experiments showed that pDNM-G supported Schwann cell proliferation and preserved cell morphology. Additionally, in a 15-mm rat sciatic nerve defect model, pDNM-G was combined with electrospun poly(lactic-acid)-co-poly(trimethylene-carbonate)conduits to bridge the defect, which did not elicit an adverse immune response and promoted the activation of M2 macrophages associated with a constructive remodeling response. Morphological analyses and electrophysiological and functional examinations revealed that the regenerative outcomes achieved by pDNM-G were superior to those by empty conduits and closed to those using rat decellularized nerve matrix allograft scaffolds. These findings indicated that pDNM-G, with its preserved ECM composition and nanofibrous structure, represents a promising biomaterial for peripheral nerve regeneration. Decellularized nerve allografts have been widely used to treat peripheral nerve injury. However, given their limited availability and lack of bioactive factors, efforts have been made to improve the efficacy

Sleep deprivation aggravates median nerve injury-induced neuropathic pain and enhances microglial activation by suppressing melatonin secretion.

Science.gov (United States)

Huang, Chun-Ta; Chiang, Rayleigh Ping-Ying; Chen, Chih-Li; Tsai, Yi-Ju

2014-09-01

Sleep deprivation is common in patients with neuropathic pain, but the effect of sleep deprivation on pathological pain remains uncertain. This study investigated whether sleep deprivation aggravates neuropathic symptoms and enhances microglial activation in the cuneate nucleus (CN) in a median nerve chronic constriction injury (CCI) model. Also, we assessed if melatonin supplements during the sleep deprived period attenuates these effects. Rats were subjected to sleep deprivation for 3 days by the disc-on-water method either before or after CCI. In the melatonin treatment group, CCI rats received melatonin supplements at doses of 37.5, 75, 150, or 300 mg/kg during sleep deprivation. Melatonin was administered at 23:00 once a day. Male Sprague-Dawley rats, weighing 180-250 g (n = 190), were used. Seven days after CCI, behavioral testing was conducted, and immunohistochemistry, immunoblotting, and enzyme-linked immunosorbent assay were used for qualitative and quantitative analyses of microglial activation and measurements of proinflammatory cytokines. In rats who underwent post-CCI sleep deprivation, microglia were more profoundly activated and neuropathic pain was worse than those receiving pre-CCI sleep deprivation. During the sleep deprived period, serum melatonin levels were low over the 24-h period. Administration of melatonin to CCI rats with sleep deprivation significantly attenuated activation of microglia and development of neuropathic pain, and markedly decreased concentrations of proinflammatory cytokines. Sleep deprivation makes rats more vulnerable to nerve injury-induced neuropathic pain, probably because of associated lower melatonin levels. Melatonin supplements to restore a circadian variation in melatonin concentrations during the sleep deprived period could alleviate nerve injury-induced behavioral hypersensitivity. © 2014 Associated Professional Sleep Societies, LLC.

Remote-Activated Electrical Stimulation via Piezoelectric Scaffold System for Functional Peripheral and Central Nerve Regeneration

OpenAIRE

Low, Karen Gail

2017-01-01

A lack of therapeutic technologies that enable electrically stimulating nervous tissues in a facile and clinically relevant manner has partly hindered the advancement in treating nerve injuries for full functional recovery. Currently, the gold standard for nerve repair is autologous nerve grafting. However, this method has several disadvantages, such as necessity for multiple surgeries, creation of functionally impaired region where graft was taken from, disproportion of graft to nerve tissue...

Exposure to a high-fat diet during development alters leptin and ghrelin sensitivity and elevates renal sympathetic nerve activity and arterial pressure in rabbits.

Science.gov (United States)

Prior, Larissa J; Davern, Pamela J; Burke, Sandra L; Lim, Kyungjoon; Armitage, James A; Head, Geoffrey A

2014-02-01

Exposure to maternal obesity or a maternal diet rich in fat during development may have adverse outcomes in offspring, such as the development of obesity and hypertension. The present study examined the effect of a maternal high-fat diet (m-HFD) on offspring blood pressure and renal sympathetic nerve activity, responses to stress, and sensitivity to central administration of leptin and ghrelin. Offspring of New Zealand white rabbits fed a 13% HFD were slightly heavier than offspring from mothers fed a 4% maternal normal fat diet (Pfat pad mass (P=0.015). Mean arterial pressure, heart rate, and renal sympathetic nerve activity at 4 months of age were 7%, 7%, and 24% greater, respectively (Pfat diet rabbits, and the renal sympathetic nerve activity response to airjet stress was enhanced in the m-HFD group. m-HFD offspring had markedly elevated pressor and renal sympathetic nerve activity responses to intracerebroventricular leptin (5-100 µg) and enhanced sympathetic responses to intracerebroventricular ghrelin (1-5 nmol). In contrast, there was resistance to the anorexic effects of intracerebroventricular leptin and less neuronal activation as detected by Fos immunohistochemistry in the arcuate (-57%; Pfat diet rabbits. We conclude that offspring from mothers consuming an HFD exhibit an adverse cardiovascular profile in adulthood because of altered central hypothalamic sensitivity to leptin and ghrelin.

Electrophysiology of Cranial Nerve Testing: Spinal Accessory and Hypoglossal Nerves.

Science.gov (United States)

Stino, Amro M; Smith, Benn E

2018-01-01

Multiple techniques have been developed for the electrodiagnostic evaluation of cranial nerves XI and XII. Each of these carries both benefits and limitations, with more techniques and data being available in the literature for spinal accessory than hypoglossal nerve evaluation. Spinal accessory and hypoglossal neuropathy are relatively uncommon cranial mononeuropathies that may be evaluated in the outpatient electrodiagnostic laboratory setting. A review of available literature using PubMed was conducted regarding electrodiagnostic technique in the evaluation of spinal accessory and hypoglossal nerves searching for both routine nerve conduction studies and repetitive nerve conduction studies. The review provided herein provides a resource by which clinical neurophysiologists may develop and implement clinical and research protocols for the evaluation of both of these lower cranial nerves in the outpatient setting.

Hip adductor activations during run-to-cut maneuvers in compression shorts: Implications for return to sport after groin injury

Science.gov (United States)

CHAUDHARI, AJIT M. W.; JAMISON, STEVEN T.; MCNALLY, MICHAEL P.; PAN, XUELIANG; SCHMITT, LAURA C.

2014-01-01

Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention or recovery from hip adductor strains. Large eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut maneuvers in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all pshorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts. PMID:24669858

Diabetic neuropathy: structural analysis of nerve hydration by Magnetic Resonance Spectroscopy

International Nuclear Information System (INIS)

Griffey, R.H.; Eaton, P.; Sibbitt, R.R.; Sibbitt, W.L. Jr.; Bicknell, J.M.

1988-01-01

The water content of the sural nerve of diabetic patients was quantitatively defined by magnetic resonance proton imaging as a putative reflection of activity of the aldose-reductase pathway. Thirty-nine patients were evaluated, comparing group A, symptomatic diabetic men with sensory neuropathy; group B, similarly symptomatic diabetic men treated aldose-reductase inhibition; group C, neurologically asymptomatic diabetic men; and group D, control nondiabetic men. Marked increase in hydration of the sural nerve was seen in more than half of the symptomatic diabetic patients. Two of 11 neurologically asymptomatic diabetics had increased nerve hydration, suggesting a presymptomatic alteration of the nerve. Symptomatic diabetics treated with aldose-reductase inhibitors had normal nerve water levels. Increased level of peripheral nerve water represents a new finding in diabetes mellitus. It seems to be related to aldose-reductase activity, involved in the development of neuropathy, and similar to events that occur in other target tissue in human diabetes

Evaluation of Morphological and Functional Nerve Recovery of Rat Sciatic Nerve with a Hyaff11-Based Nerve Guide

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K. Jansen

2006-01-01

Full Text Available Application of a Hyaff11-based nerve guide was studied in rats. Functional tests were performed to study motor nerve recovery. A withdrawal reflex test was performed to test sensory recovery. Morphology was studied by means of histology on explanted tissue samples. Motor nerve recovery was established within 7 weeks. Hereafter, some behavioral parameters like alternating steps showed an increase in occurence, while others remained stable. Sensory function was observed within the 7 weeks time frame. Nerve tissue had bridged the 10-mm gap within 7 weeks. The average nerve fiber surface area increased significantly in time. In situ degradation of the nerve conduit was fully going on at week 7 and tubes had collapsed by then. At weeks 15 and 21, the knitted tube wall structure was completely surrounded by macrophages and giant cells, and matrix was penetrating the tube wall. We conclude that a Hyaff11-based nerve guide can be used to bridge short peripheral nerve defects in rat. However, adaptations need to be made.

[Facial nerve neurinomas].

Science.gov (United States)

Sokołowski, Jacek; Bartoszewicz, Robert; Morawski, Krzysztof; Jamróz, Barbara; Niemczyk, Kazimierz

2013-01-01

Evaluation of diagnostic, surgical technique, treatment results facial nerve neurinomas and its comparison with literature was the main purpose of this study. Seven cases of patients (2005-2011) with facial nerve schwannomas were included to retrospective analysis in the Department of Otolaryngology, Medical University of Warsaw. All patients were assessed with history of the disease, physical examination, hearing tests, computed tomography and/or magnetic resonance imaging, electronystagmography. Cases were observed in the direction of potential complications and recurrences. Neurinoma of the facial nerve occurred in the vertical segment (n=2), facial nerve geniculum (n=1) and the internal auditory canal (n=4). The symptoms observed in patients were analyzed: facial nerve paresis (n=3), hearing loss (n=2), dizziness (n=1). Magnetic resonance imaging and computed tomography allowed to confirm the presence of the tumor and to assess its staging. Schwannoma of the facial nerve has been surgically removed using the middle fossa approach (n=5) and by antromastoidectomy (n=2). Anatomical continuity of the facial nerve was achieved in 3 cases. In the twelve months after surgery, facial nerve paresis was rated at level II-III° HB. There was no recurrence of the tumor in radiological observation. Facial nerve neurinoma is a rare tumor. Currently surgical techniques allow in most cases, the radical removing of the lesion and reconstruction of the VII nerve function. The rate of recurrence is low. A tumor of the facial nerve should be considered in the differential diagnosis of nerve VII paresis. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

The Effects of Phrenic Nerve Degeneration by Axotomy and Crush on the Electrical Activities of Diaphragm Muscles of Rats.

Science.gov (United States)

Alkiş, Mehmet Eşref; Kavak, Servet; Sayır, Fuat; Him, Aydin

2016-03-01

The aim of this study was to investigate the effect of axotomy and crush-related degeneration on the electrical activities of diaphragm muscle strips of experimental rats. In the present study, twenty-one male Wistar-albino rats were used and divided into three groups. The animals in the first group were not crushed or axotomized and served as controls. Phrenic nerves of the rats in the second and third groups were crushed or axotomized in the diaphragm muscle. Resting membrane potential (RMP) was decreased significantly in both crush and axotomy of diaphragm muscle strips of experimental rats (p phrenic nerves may produce electrical activities in the diaphragm muscle of the rat by depolarization time and half-repolarization time prolonged in crush and axotomy rats.

Compression and release dynamics of an active matter system of Euglena gracilis

Science.gov (United States)

Lam, Amy; Tsang, Alan C. H.; Ouellette, Nicholas; Riedel-Kruse, Ingmar

Active matter, defined as ensembles of self-propelled particles, encompasses a large variety of systems at all scales, from nanoparticles to bird flocks. Though various models and simulations have been created to describe the dynamics of these systems, experimental verification has been difficult to obtain. This is frequently due to the complex interaction rules which govern the particle behavior, in turn making systematic varying of parameters impossible. Here, we propose a model for predicting the system evolution of compression and release of an active system based on experiments and simulations. In particular, we consider ensembles of the unicellular, photo-responsive algae, Euglena gracilis, under light stimulation. By varying the spatiotemporal light patterns, we are able to finely adjust cell densities and achieve arbitrary non-homogeneous distributions, including compression into high-density aggregates of varying geometries. We observe the formation of depletion zones after the release of the confining stimulus and investigate the effects of the density distribution and particle rotational noise on the depletion. These results provide implications for defining state parameters which determine system evolution.

Use of superficial peroneal nerve graft for treating peripheral nerve injuries

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Samuel Ribak

2016-02-01

Full Text Available ABSTRACT OBJECTIVE: To evaluate the clinical results from treating chronic peripheral nerve injuries using the superficial peroneal nerve as a graft donor source. METHODS: This was a study on eleven patients with peripheral nerve injuries in the upper limbs that were treated with grafts from the sensitive branch of the superficial peroneal nerve. The mean time interval between the dates of the injury and surgery was 93 days. The ulnar nerve was injured in eight cases and the median nerve in six. There were three cases of injury to both nerves. In the surgery, a longitudinal incision was made on the anterolateral face of the ankle, thus viewing the superficial peroneal nerve, which was located anteriorly to the extensor digitorum longus muscle. Proximally, the deep fascia between the extensor digitorum longus and the peroneal longus muscles was dissected. Next, the motor branch of the short peroneal muscle (one of the branches of the superficial peroneal nerve was identified. The proximal limit of the sensitive branch was found at this point. RESULTS: The average space between the nerve stumps was 3.8 cm. The average length of the grafts was 16.44 cm. The number of segments used was two to four cables. In evaluating the recovery of sensitivity, 27.2% evolved to S2+, 54.5% to S3 and 18.1% to S3+. Regarding motor recovery, 72.7% presented grade 4 and 27.2% grade 3. There was no motor deficit in the donor area. A sensitive deficit in the lateral dorsal region of the ankle and the dorsal region of the foot was observed. None of the patients presented complaints in relation to walking. CONCLUSIONS: Use of the superficial peroneal nerve as a graft source for treating peripheral nerve injuries is safe and provides good clinical results similar to those from other nerve graft sources.

Delayed peripheral nerve repair: methods, including surgical 'cross-bridging' to promote nerve regeneration.

Science.gov (United States)

Gordon, Tessa; Eva, Placheta; Borschel, Gregory H

2015-10-01

Despite the capacity of Schwann cells to support peripheral nerve regeneration, functional recovery after nerve injuries is frequently poor, especially for proximal injuries that require regenerating axons to grow over long distances to reinnervate distal targets. Nerve transfers, where small fascicles from an adjacent intact nerve are coapted to the nerve stump of a nearby denervated muscle, allow for functional return but at the expense of reduced numbers of innervating nerves. A 1-hour period of 20 Hz electrical nerve stimulation via electrodes proximal to an injury site accelerates axon outgrowth to hasten target reinnervation in rats and humans, even after delayed surgery. A novel strategy of enticing donor axons from an otherwise intact nerve to grow through small nerve grafts (cross-bridges) into a denervated nerve stump, promotes improved axon regeneration after delayed nerve repair. The efficacy of this technique has been demonstrated in a rat model and is now in clinical use in patients undergoing cross-face nerve grafting for facial paralysis. In conclusion, brief electrical stimulation, combined with the surgical technique of promoting the regeneration of some donor axons to 'protect' chronically denervated Schwann cells, improves nerve regeneration and, in turn, functional outcomes in the management of peripheral nerve injuries.

A Physicochemically Optimized and Neuroconductive Biphasic Nerve Guidance Conduit for Peripheral Nerve Repair.

Science.gov (United States)

Ryan, Alan J; Lackington, William A; Hibbitts, Alan J; Matheson, Austyn; Alekseeva, Tijna; Stejskalova, Anna; Roche, Phoebe; O'Brien, Fergal J

2017-12-01

Clinically available hollow nerve guidance conduits (NGCs) have had limited success in treating large peripheral nerve injuries. This study aims to develop a biphasic NGC combining a physicochemically optimized collagen outer conduit to bridge the transected nerve, and a neuroconductive hyaluronic acid-based luminal filler to support regeneration. The outer conduit is mechanically optimized by manipulating crosslinking and collagen density, allowing the engineering of a high wall permeability to mitigate the risk of neuroma formation, while also maintaining physiologically relevant stiffness and enzymatic degradation tuned to coincide with regeneration rates. Freeze-drying is used to seamlessly integrate the luminal filler into the conduit, creating a longitudinally aligned pore microarchitecture. The luminal stiffness is modulated to support Schwann cells, with laminin incorporation further enhancing bioactivity by improving cell attachment and metabolic activity. Additionally, this biphasic NGC is shown to support neurogenesis and gliogenesis of neural progenitor cells and axonal outgrowth from dorsal root ganglia. These findings highlight the paradigm that a successful NGC requires the concerted optimization of both a mechanical support phase capable of bridging a nerve defect and a neuroconductive phase with an architecture capable of supporting both Schwann cells and neurons in order to achieve functional regenerative outcome. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thrombosed persistent median artery causing carpal tunnel syndrome associated with bifurcated median nerve: A case report

International Nuclear Information System (INIS)

Salter, M.; Sinha, N. R.; Szmigielski, W.

2011-01-01

Background: Carpal tunnel syndrome is a sporadically occurring abnormality due to compression of median nerve. It is exceedingly rare for it to be caused by thrombosis of persistent median artery. Case Report: A forty two year old female was referred for ultrasound examination due to ongoing wrist pain, not relived by pain killers and mild paraesthesia on the radial side of the hand. High resolution ultrasound and Doppler revealed a thrombosed persistent median artery and associated bifurcated median nerve. The thrombus resolved on treatment with anticoagulants. Conclusions: Ultrasound examination of the wrist when done for patients with carpal tunnel syndrome should preferably include looking for persistent median artery and its patency. (authors)

Sensory nerve function and auto-mutilation after reconstruction of various gap lengths with nerve guides and autologous nerve grafts

NARCIS (Netherlands)

den Dunnen, WFA; Meek, MF

The aim of this study was to evaluate sensory nerve recovery and auto-mutilation after reconstruction of various lengths of nerve gaps in the sciatic nerve of the rat, using different techniques. Group 4, in which the longest nerve gap (15 mm) was reconstructed with a thin-walled

Facial nerve injury following surgery for temporomandibular joint ankylosis: A prospective clinical study

Directory of Open Access Journals (Sweden)

S Gokkulakrishnan

2013-01-01

Full Text Available Objective: The purpose of this prospective study was to evaluate the incidence and degree of facial nerve damage and time taken for its recovery following surgery for temporomandibular joint (TMJ ankylosis. Materials and Methods: A total of 30 subjects with the TMJ ankylosis with or without history of previous surgery were included in this prospective study. House-Brackmann grading system was used to assess the function of the facial nerve post-operatively. Results: Most of the subjects were in the age range of 13-15 years. Eight subjects had bilateral ankylosis and remaining 22 had unilateral ankylosis. Out of 32 joints in which gap arthroplasty was performed, 4 had Grade 1 injury, 14 had Grade 2 injury, 12 had Grade 3, and 2 with the Grade 4 injury 24 h post-operatively. Whereas, out of 6 cases of interpositional arthroplasty 4 had Grade 1 injury and 2 had Grade 4 injury. According to House-Brackmann grading system, at 24 h, 78.9% patients had different grades of facial nerve injury, which gradually improved and came to normal limits within 1-3 months post-operatively. Comparison of change in the Grade of injury at 3 months follow-up as compared to baseline (24 h showed full recovery in all the cases (100% showing a statistically significant difference from baseline (P < 0.001. Conclusion: When proper care is taken during surgery for TMJ ankylosis, permanent facial nerve injury is rare. However, the incidence and degree of temporary nerve injury could be either due to the heavy retraction causing compression and or stretching of nerve fiber resulting in neuropraxia.

Tissue-engineered rhesus monkey nerve grafts for the repair of long ulnar nerve defects: similar outcomes to autologous nerve grafts

Directory of Open Access Journals (Sweden)

Chang-qing Jiang

2016-01-01

Full Text Available Acellular nerve allografts can help preserve normal nerve structure and extracellular matrix composition. These allografts have low immunogenicity and are more readily available than autologous nerves for the repair of long-segment peripheral nerve defects. In this study, we repaired a 40-mm ulnar nerve defect in rhesus monkeys with tissue-engineered peripheral nerve, and compared the outcome with that of autograft. The graft was prepared using a chemical extract from adult rhesus monkeys and seeded with allogeneic Schwann cells. Pathomorphology, electromyogram and immunohistochemistry findings revealed the absence of palmar erosion or ulcers, and that the morphology and elasticity of the hypothenar eminence were normal 5 months postoperatively. There were no significant differences in the mean peak compound muscle action potential, the mean nerve conduction velocity, or the number of neurofilaments between the experimental and control groups. However, outcome was significantly better in the experimental group than in the blank group. These findings suggest that chemically extracted allogeneic nerve seeded with autologous Schwann cells can repair 40-mm ulnar nerve defects in the rhesus monkey. The outcomes are similar to those obtained with autologous nerve graft.

Tissue-engineered rhesus monkey nerve gratfs for the repair of long ulnar nerve defects：similar outcomes to autologous nerve gratfs

Institute of Scientific and Technical Information of China (English)

Chang-qing Jiang; Jun Hu; Jian-ping Xiang; Jia-kai Zhu; Xiao-lin Liu; Peng Luo

2016-01-01

Acellular nerve allogratfs can help preserve normal nerve structure and extracellular matrix composition. These allogratfs have low immu-nogenicity and are more readily available than autologous nerves for the repair of long-segment peripheral nerve defects. In this study, we repaired a 40-mm ulnar nerve defect in rhesus monkeys with tissue-engineered peripheral nerve, and compared the outcome with that of autogratf. The gratf was prepared using a chemical extract from adult rhesus monkeys and seeded with allogeneic Schwann cells. Pathomo-rphology, electromyogram and immunohistochemistry ifndings revealed the absence of palmar erosion or ulcers, and that the morphology and elasticity of the hypothenar eminence were normal 5 months postoperatively. There were no signiifcant differences in the mean peak compound muscle action potential, the mean nerve conduction velocity, or the number of neuroiflaments between the experimental and control groups. However, outcome was signiifcantly better in the experimental group than in the blank group. These ifndings suggest that chemically extracted allogeneic nerve seeded with autologous Schwann cells can repair 40-mm ulnar nerve defects in the rhesus monkey. The outcomes are similar to those obtained with autologous nerve gratf.

Study of nerve fibers nature reinforcing duodenal contractions by electrical stimulation of sympathetic nerve

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Sveshnikov D.S.

2011-09-01

Full Text Available The subject of the article is to investigate the mechanism of increased reactions by electrical stimulation of the sympathetic nerve. Materials and methods: Experiments on dogs have shown that stimulant reactions during blockade of a-adrenergic by phentolamine and (3-adrenergic receptors with propranolol were completely eliminated by lizer-gol —the blocker of 5-HT12-receptors. Results: Infusion of lizergol did not influence on duodenal motor activity and the function of the vagus nerve. Conclusion: Effector neuron is found out to be serotonergic and its action is provided by 5-HT1 2 receptors

Overview of the testing activities on ITER sub-scale pre-compression rings

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Rossi, Paolo, E-mail: paolo.rossi@enea.it [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Capobianchi, Mario; Crescenzi, Fabio; Massimi, Alberto; Mugnaini, Giampiero; Pizzuto, Aldo [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Knaster, Juan [ITER Organisation, Route de Vinon sur Verdon, 13115, St. Paul lez Durance (France); Rajainmaki, Hannu [FUSION FOR ENERGY, Josep Pla no. 2, Torres Diagonal Litoral Edificio B3, 08019 Barcelona (Spain)

2012-08-15

Highlights: Black-Right-Pointing-Pointer ENEA developed a high strength glass fiber-epoxy composite for ITER pre-compression rings. Black-Right-Pointing-Pointer High UTS values were obtained at RT on linear specimens (2200 MPa) and on scaled ring mock-ups (1550 MPa). Black-Right-Pointing-Pointer Creep tests showed very low creep strain and creep rates. Black-Right-Pointing-Pointer Long term tests showed no significant stress relaxation on the ring mock-ups. - Abstract: After a first R and D and testing activity to develop and characterize by tensile and creep tests a high strength glass fiber-epoxy composite as reference material for the manufacture of ITER pre-compression rings, ENEA designed and manufactured a dedicated testing facility and different sub-scale composite ring mock-ups in order to characterize their mechanical properties. The paper reports the results of the overall testing activities performed during the last years on a total number of eleven sub-scale pre-compression ring mock-ups manufactured by winding S2 glass fibers on a diameter of 1 m (1/5 of the full scale) both by vacuum pressure epoxy impregnation (VPI) and filament wet winding techniques (WW). The first three rings were manufactured by ENEA Frascati thanks to a particular VPI technique; one of them was used as base composite material to manufacture different sets of specimens for shear, compression and non destructive tests (NDT). Then, five other mock-ups were manufactured following ENEA VPI process and three using WW technique by two different industrial companies. The rings were tested in ENEA Frascati in a dedicated hydraulic testing machine consisting of 18 radial actuators working in position control with a total load capability of 1000 tons. The complete testing campaign consisted of six ultimate tensile strength (UTS) tests and four stress relaxation (SR) tests. The tests demonstrated that the composite (S2 glass-epoxy) is a valid and viable solution for the ITER pre-compression