Anti-Seizure Medications: Relief from Nerve Pain

MedlinePlus

... be debilitating and difficult to control. Nerve damage (neuropathy) can be caused by many conditions, including: Diabetes. ... and pain in your hands and feet (diabetic neuropathy). Shingles. Anyone who has had chickenpox is at ...

Nerve damage related to implant dentistry: incidence, diagnosis, and management.

PubMed

Greenstein, Gary; Carpentieri, Joseph R; Cavallaro, John

2015-10-01

Proper patient selection and treatment planning with respect to dental implant placement can preclude nerve injuries. Nevertheless, procedures associated with implant insertion can inadvertently result in damage to branches of the trigeminal nerve. Nerve damage may be transient or permanent; this finding will depend on the cause and extent of the injury. Nerve wounding may result in anesthesia, paresthesia, or dysesthesia. The type of therapy to ameliorate the condition will be dictated by clinical and radiographic assessments. Treatment may include monitoring altered sensations to see if they subside, pharmacotherapy, implant removal, reverse-torquing an implant to decompress a nerve, combinations of the previous therapies, and/or referral to a microsurgeon for nerve repair. Patients manifesting altered sensations due to various injuries require different therapies. Transection of a nerve dictates immediate referral to a microsurgeon for evaluation. If a nerve is compressed by an implant or adjacent bone, the implant should be reverse-torqued away from the nerve or removed. When an implant is not close to a nerve, but the patient is symptomatic, the patient can be monitored and treated pharmacologically as long as symptoms improve or the implant can be removed. There are diverse opinions in the literature concerning how long an injured patient should be monitored before being referred to a microsurgeon.

Soman increases neuronal COX-2 levels: possible link between seizures and protracted neuronal damage.

PubMed

Angoa-Pérez, Mariana; Kreipke, Christian W; Thomas, David M; Van Shura, Kerry E; Lyman, Megan; McDonough, John H; Kuhn, Donald M

2010-12-01

Nerve agent-induced seizures cause neuronal damage in brain limbic and cortical circuits leading to persistent behavioral and cognitive deficits. Without aggressive anticholinergic and benzodiazepine therapy, seizures can be prolonged and neuronal damage progresses for extended periods of time. The objective of this study was to determine the effects of the nerve agent soman on expression of cyclooxygenase-2 (COX-2), the initial enzyme in the biosynthetic pathway of the proinflammatory prostaglandins and a factor that has been implicated in seizure initiation and propagation. Rats were exposed to a toxic dose of soman and scored behaviorally for seizure intensity. Expression of COX-2 was determined throughout brain from 4h to 7 days after exposure by immunohistochemistry and immunoblotting. Microglial activation and astrogliosis were assessed microscopically over the same time-course. Soman increased COX-2 expression in brain regions known to be damaged by nerve agents (e.g., hippocampus, amygdala, piriform cortex and thalamus). COX-2 expression was induced in neurons, and not in microglia or astrocytes, and remained elevated through 7 days. The magnitude of COX-2 induction was correlated with seizure intensity. COX-1 expression was not changed by soman. Increased expression of neuronal COX-2 by soman is a late-developing response relative to other signs of acute physiological distress caused by nerve agents. COX-2-mediated production of prostaglandins is a consequence of the seizure-induced neuronal damage, even after survival of the initial cholinergic crisis is assured. COX-2 inhibitors should be considered as adjunct therapy in nerve agent poisoning to minimize nerve agent-induced seizure activity. Published by Elsevier B.V.

Radiation treatment inhibits monocyte entry into the optic nerve head and prevents neuronal damage in a mouse model of glaucoma

PubMed Central

Howell, Gareth R.; Soto, Ileana; Zhu, Xianjun; Ryan, Margaret; Macalinao, Danilo G.; Sousa, Gregory L.; Caddle, Lura B.; MacNicoll, Katharine H.; Barbay, Jessica M.; Porciatti, Vittorio; Anderson, Michael G.; Smith, Richard S.; Clark, Abbot F.; Libby, Richard T.; John, Simon W.M.

2012-01-01

Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve. PMID:22426214

Acute and subacute effects of the ultrasonic blade and electrosurgery on nerve physiology.

PubMed

Chen, Chaoyang; Kallakuri, Srinivasu; Cavanaugh, John M; Broughton, Duan; Clymer, Jeffrey W

2015-01-01

Ultrasonic blades have been shown to cause less acute electrophysiological damage when applied near nerves than monopolar electrosurgery (ES). This study was performed to determine whether the acute nerve damage observed for ES, as well as the relative lack of damage observed for ultrasonic dissection, extends through a subacute timeframe. Muscle incisions were made in rat with the Harmonic(®) Blade (HB) and ES at a distance of 2 mm from the sciatic nerve. Sham surgery was also performed which consisted of similar exposure of the sciatic nerve without use of an energized device. Electrophysiological function was assessed acutely over a 3-h period, and subacutely after a 7-day survival, by monitoring the sciatic nerve compound action potential (CAP), conduction velocity (CV), von Frey hair (VFH) stimulation force, leukocyte infiltration, and impaired axonal transport via β-amyloid precursor protein (β-APP) immunocytochemistry. During the acute period, ES produced significantly lower CAP and CV, and higher levels of leukocytes and β-APP than sham, whereas the ultrasonic blade was not significantly different from sham, and had significantly lower VFH force than ES. After the subacute survival, ES continued to display significantly lower CAP and CV, and higher levels of leukocytes and β-APP than sham, whereas ultrasonic blade had higher CAP and CV than sham, and lower VFH than ES. This study confirms that incisions made with an ultrasonic blade cause less acute nerve damage than monopolar ES, and are comparable to sham surgery at a distance of 2 mm from the sciatic nerve. The negative effects of electrosurgery extend through at least a 7-day survival period, whereas subacute recovery after application of the ultrasonic blade was comparable to that of sham surgery. For surgical procedures in the vicinity of vital nerves, use of the ultrasonic blade represents a lower risk than ES for both acute and subacute neural trauma.

Unilateral blindness with third cranial nerve palsy and abnormal enhancement of extraocular muscles on magnetic resonance imaging of orbit after the ingestion of methanol.

PubMed

Chung, Tae Nyoung; Kim, Sun Wook; Park, Yoo Seok; Park, Incheol

2010-05-01

Methanol is generally known to cause visual impairment and various systemic manifestations. There are a few reported specific findings for methanol intoxication on magnetic resonance imaging (MRI) of the brain. A case is reported of unilateral blindness with third cranial nerve palsy oculus sinister (OS) after the ingestion of methanol. Unilateral damage of the retina and optic nerve were confirmed by fundoscopy, flourescein angiography, visual evoked potential and electroretinogram. The optic nerve and extraocular muscles (superior rectus, medial rectus, inferior rectus and inferior oblique muscle) were enhanced by gadolinium-DTPA on MRI of the orbit. This is the first case report of permanent monocular blindness with confirmed unilateral damage of the retina and optic nerve, combined with third cranial nerve palsy after methanol ingestion.

Microglial activation is a pharmacologically specific marker for the neurotoxic amphetamines.

PubMed

Thomas, David M; Dowgiert, Jennifer; Geddes, Timothy J; Francescutti-Verbeem, Dina; Liu, Xiuli; Kuhn, Donald M

2004-09-09

Neurotoxic amphetamines cause damage to monoamine nerve terminals of the striatum by unknown mechanisms. Microglial activation contributes to the neuronal damage that accompanies injury, disease, and inflammation, but a role for these cells in amphetamine-induced neurotoxicity has received little attention. We show presently that D-methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), D-amphetamine, and p-chloroamphetamine, each of which has been linked to dopamine (DA) or serotonin nerve terminal damage, result in microglial activation in the striatum. The non-neurotoxic amphetamines l-methamphetamine, fenfluramine, and DOI do not have this effect. All drugs that cause microglial activation also increase expression of glial fibrillary acidic protein (GFAP). At a minimum, microglial activation serves as a pharmacologically specific marker for striatal nerve terminal damage resulting only from those amphetamines that exert neurotoxicity. Because microglia are known to produce many of the reactive species (e.g., nitric oxide, superoxide, cytokines) that mediate the neurotoxicity of the amphetamine-class of drugs, their activation could represent an early and essential event in the neurotoxic cascade associated with high-dose amphetamine intoxication.

Can proximity of the occipital artery to the greater occipital nerve act as a cause of idiopathic greater occipital neuralgia? An anatomical and histological evaluation of the artery-nerve relationship.

PubMed

Shimizu, Satoru; Oka, Hidehiro; Osawa, Shigeyuki; Fukushima, Yutaka; Utsuki, Satoshi; Tanaka, Ryusui; Fujii, Kiyotaka

2007-06-01

The purpose of this study was to clarify whether proximity of the occipital artery to the greater occipital nerve can act as a cause of occipital neuralgia, analogous to the contribution of intracranial vessels due to compression in cranial nerve neuralgias, represented by trigeminal neuralgias due to compression of the trigeminal nerve root by adjacent arterial loops. Twenty-four suboccipital areas in cadaver heads were studied for anatomical relationships between the occipital artery and the greater occipital nerve, with histopathological assessment of the greater occipital nerve for signs of mechanical damage. The occipital artery and greater occipital nerve were found to cross each other in the nuchal subcutaneous layer, and the latter was constantly situated superficial to the former at the cross point. An indentation of the greater occipital nerve due to the occipital artery was observed at the cross point in all specimens. However, histopathological examination did not reveal any findings of damage to nerves, even in specimens with atherosclerosis of the occipital artery. Although the present study did not provide direct evidence that the occipital artery contributes to occipital neuralgia at the point of contact with the greater occipital nerve, the possibility still cannot be precluded, because the occipital artery may be palpable in areas corresponding to tenderness of the greater occipital nerve. Further studies, including clinical cases, are needed to clarify this issue.

Autonomic neuropathy resulting in recurrent laryngeal nerve palsy in an HIV patient with Hodgkin lymphoma receiving vinblastine and antiretroviral therapy.

PubMed

Cherif, S; Danino, S; Yoganathan, K

2015-03-01

Hoarseness of voice due to vocal cord paresis as a result of recurrent laryngeal nerve palsy has been well recognised. Recurrent laryngeal nerve palsy is commonly caused by compression due to tumour or lymph nodes or by surgical damage. Vinca alkaloids are well known to cause peripheral neuropathy. However, vinca alkaloids causing recurrent laryngeal nerve palsy has been reported rarely in children. We report a case of an adult patient with HIV who developed hoarseness of voice due to vocal cord paralysis during vinblastine treatment for Hodgkin lymphoma. Mediastinal and hilar lymph node enlargement in such patients may distract clinicians from considering alternative causes of recurrent laryngeal nerve palsy, with potential ensuing severe or even life-threatening stridor. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

A macrophage response to Mycobacterium leprae phenolic glycolipid initiates nerve damage in leprosy

PubMed Central

Madigan, Cressida A.; Cambier, C.J.; Kelly-Scumpia, Kindra M.; Scumpia, Philip O.; Cheng, Tan-Yun; Zailaa, Joseph; Bloom, Barry R.; Moody, D. Branch; Smale, Stephen T.; Sagasti, Alvaro; Modlin, Robert L.; Ramakrishnan, Lalita

2018-01-01

SUMMARY Mycobacterium leprae causes leprosy, and is unique among mycobacterial diseases in producing peripheral neuropathy. This debilitating morbidity is attributed to axon demyelination resulting from direct interactions of the M. leprae-specific phenolic glycolipid 1 (PGL-1) with myelinating glia, and their subsequent infection. Here, we use transparent zebrafish larvae to visualize the earliest events of M. leprae-induced nerve damage. We find that demyelination and axonal damage are not directly initiated by M. leprae but by infected macrophages that patrol axons; demyelination occurs in areas of intimate contact. PGL-1 confers this neurotoxic response on macrophages: macrophages infected with M. marinum expressing PGL-1 also damage axons. PGL-1 induces nitric oxide synthase in infected macrophages, and the resultant increase in reactive nitrogen species damages axons by injuring their mitochondria and inducing demyelination. Our findings implicate the response of innate macrophages to M. leprae PGL-1 in initiating nerve damage in leprosy. PMID:28841420

A Macrophage Response to Mycobacterium leprae Phenolic Glycolipid Initiates Nerve Damage in Leprosy.

PubMed

Madigan, Cressida A; Cambier, C J; Kelly-Scumpia, Kindra M; Scumpia, Philip O; Cheng, Tan-Yun; Zailaa, Joseph; Bloom, Barry R; Moody, D Branch; Smale, Stephen T; Sagasti, Alvaro; Modlin, Robert L; Ramakrishnan, Lalita

2017-08-24

Mycobacterium leprae causes leprosy and is unique among mycobacterial diseases in producing peripheral neuropathy. This debilitating morbidity is attributed to axon demyelination resulting from direct interaction of the M. leprae-specific phenolic glycolipid 1 (PGL-1) with myelinating glia and their subsequent infection. Here, we use transparent zebrafish larvae to visualize the earliest events of M. leprae-induced nerve damage. We find that demyelination and axonal damage are not directly initiated by M. leprae but by infected macrophages that patrol axons; demyelination occurs in areas of intimate contact. PGL-1 confers this neurotoxic response on macrophages: macrophages infected with M. marinum-expressing PGL-1 also damage axons. PGL-1 induces nitric oxide synthase in infected macrophages, and the resultant increase in reactive nitrogen species damages axons by injuring their mitochondria and inducing demyelination. Our findings implicate the response of innate macrophages to M. leprae PGL-1 in initiating nerve damage in leprosy. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Rapid New Methods for Paint Collection and Lead Extraction

EPA Science Inventory

Chronic exposure of children to lead (Ph) can result in permanent physiologic impairment. In adults, it can cause irritability, poor muscle coordination, and nerve damage to the sense organs and nerves controlling the body. Surfaces coated with Pb-containing paints are potential ...

Gastroparesis

MedlinePlus

... Causes Diagnosis Treatment Eating, Diet, & Nutrition Clinical Trials Hemorrhoids Definition & Facts Symptoms & Causes Diagnosis Treatment Eating, Diet, & ... Nerve Damage (Diabetic Neuropathies) Indigestion (Dyspepsia) Related Diagnostic Tests Upper GI Endoscopy Upper GI Series Related Research ...

[Three-month rehabilitation of a patient with the III, IV and VI cranial nerve damage caused by a neurosurgery of the left internal carotid artery aneurysm].

PubMed

Mosiński, Eliasz; Kikowski, Łukasz; Irzmański, Robert

Introduction: Oculomotor nerve palsy is an eye condition resulting from damage to the third cranial nerve or a branch thereof. Third nerve damage weakens the muscles innervated by the nerve . Also adversely affect the fourth and sixth nerve , causing impairment of their activity. Rehabilitation third nerve palsy is rarely described in the available literature . The whole process is very difficult , but the effects of physiotherapy is very beneficial for the patient. The aim:The assessment of the influence of the outpatient rehabilitation on the patient's condition after a three-month treatment and the use of physical therapy. Material and methods:Case studies of the 38-yerar-old patient after having operated a big aneurism of the left ICA, which was clipped. After the procedure, the III, IV and VI cranial nerves were deeply impaired and the amnesic aphasia occurred. The patient started the rehabilitation a month after the incident. To assess the process of rehabilitation, the own movement examination of the eyeball was implemented. Active and passive exercises, Tigger Point therapy, kinesiotaping, laser and electrostimulation were inserted. Results: The significant improvement of the eyeball movement has been proved on the basis of the same own examination. A physiotherapy has had a positive influence on the speech disorder, namely amnesic aphasia, and after the month of the rehabilitation it has been completely removed. The positive influence of the rehabilitation, which has been pointed out, is clinically essential. Conclusions: Obtained results have not been described in literature yet, that is why it is essential to widen further research and emphasise the importance of the rehabilitation, which is rarely implemented in an intense way in such medical conditions.

Molecular mimicry between Mycobacterium leprae proteins (50S ribosomal protein L2 and Lysyl-tRNA synthetase) and myelin basic protein: a possible mechanism of nerve damage in leprosy.

PubMed

Singh, Itu; Yadav, Asha Ram; Mohanty, Keshar Kunja; Katoch, Kiran; Sharma, Prashant; Mishra, Bishal; Bisht, Deepa; Gupta, U D; Sengupta, Utpal

2015-04-01

Autoantibodies against various components of host are known to occur in leprosy. Nerve damage is the primary cause of disability associated with leprosy. The aim of this study was to detect the level of autoantibodies and lympho-proliferative response against myelin basic protein (MBP) in leprosy patients (LPs) and their correlation with clinical phenotypes of LPs. Further, probable role of molecular mimicry in nerve damage of LPs was investigated. We observed significantly high level of anti-MBP antibodies in LPs across the spectrum and a positive significant correlation between the level of anti-MBP antibodies and the number of nerves involved in LPs. We report here that 4 B cell epitopes of myelin A1 and Mycobacterium leprae proteins, 50S ribosomal L2 and lysyl tRNA synthetase are cross-reactive. Further, M. leprae sonicated antigen hyperimmunization was responsible for induction of autoantibody response in mice which could be adoptively transferred to naive mice. For the first time our findings suggest the role of molecular mimicry in nerve damage in leprosy. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

How do I manage an acute injury to the facial nerve?

PubMed

Colbert, Serryth; Coombes, Daryl; Godden, Daryl; Cascarini, Luke; Kerawala, Cyrus; Brennan, Peter A

2014-01-01

Paralysis of the facial nerve is a cause of considerable functional and aesthetic disfigurement. Damage to the upper trunk can result in eye complications with the risk of exposure keratitis. Numerous factors influence the therapeutic strategy: the cause of the injury, the time elapsed since injury, functional impairment, and the likelihood of recovery. We discuss the management of an acute injury to the facial nerve and focus on the surgical options. Copyright © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Renal denervation using focused infrared fiber lasers: a potential treatment for hypertension.

PubMed

Alexander, Vinay V; Shi, Zhennan; Iftekher, Fariha; Welsh, Michael J; Gurm, Hitinder S; Rising, Gail; Yanovich, Amber; Walacavage, Kim; Islam, Mohammed N

2014-11-01

Renal denervation has recently become of great interest as a potential treatment for resistant hypertension. Denervation techniques using radio frequency (RF) or ultrasound energy sources have already been explored in literature. In this study, we investigate the use of lasers as a potential energy source for renal denervation. In vitro studies are performed in porcine/ovine renal arteries with focused laser beams at 980 nm, 1210 nm, and 1700 nm to study the ability to damage renal nerves without causing injury to non-target tissue structures like the endothelium. Then, a 980 nm laser catheter prototype is built and used to demonstrate in vivo renal denervation in ovine renal arteries. This study utilizes fiber coupled infrared lasers at 980 nm, 1210 nm, and 1700 nm. In vitro laser denervation studies at 980 nm are performed in both porcine and ovine renal arteries to study the ability of focused laser beams to damage renal nerves without injuring the endothelium. In vitro studies using lasers close to the lipid absorption lines at 1210 nm and 1700 nm are also performed in porcine renal arteries to study the possibility of selectively damaging the renal nerves by targeting the lipid myelin sheaths surrounding the nerves. Then, a laser catheter prototype is designed and built for in vivo renal denervation in ovine renal arteries using the 980 nm laser (powers ranging from 2 to 4 W, 5 seconds per exposure). Histochemical evaluations of the frozen sections are performed using methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. Histochemical analysis of in vitro laser treatments at 980 nm in porcine and ovine renal arteries show clear evidence of laser-induced renal nerve damage without injury to the endothelium and part of the media. No evidence of selective nerve damage is observed using the 1210 nm and 1700 nm lasers with the current treatment parameters. Histochemical analysis of in vivo laser treatments in ovine renal arteries using a focused 980 nm laser show clear evidence of renal nerve damage with depths of damage extending > 1.5 mm from the artery wall. Sections with laser-induced damage to the media/adventitia at depths of > 1 mm without injury to the endothelium are also observed. We demonstrate the use of focused lasers as an attractive energy source for causing renal nerve damage without injury to the artery wall and thus, may have potential therapeutic applications for conditions such as resistant hypertension, where renal denervation has been shown to be a promising form of treatment. © 2014 Wiley Periodicals, Inc.

3,4-Methylenedioxypyrovalerone prevents while methylone enhances methamphetamine-induced damage to dopamine nerve endings: β-ketoamphetamine modulation of neurotoxicity by the dopamine transporter

PubMed Central

Anneken, John H.; Angoa-Pérez, Mariana; Kuhn, Donald M.

2016-01-01

Methylone, 3,4-methylenedioxypyrovalerone (MDPV), and mephedrone are psychoactive ingredients of ‘bath salts’ and their abuse represents a growing public health care concern. These drugs are cathinone derivatives and are classified chemically as β-ketoamphetamines. Because of their close structural similarity to the amphetamines, methylone, MDPV, and mephedrone share most of their pharmacological, neurochemical, and behavioral properties. One point of divergence in their actions is the ability to cause damage to the CNS. Unlike methamphetamine, the β-ketoamphetamines do not damage dopamine (DA) nerve endings. However, mephedrone has been shown to significantly accentuate methamphetamine neurotoxicity. Bath salt formulations contain numerous different psychoactive ingredients, and individuals who abuse bath salts also coabuse other illicit drugs. Therefore, we have evaluated the effects of methylone, MDPV, mephedrone, and methamphetamine on DA nerve endings. The β-ketoamphetamines alone or in all possible two-drug combinations do not result in damage to DA nerve endings but do cause hyperthermia. MDPV completely protects against the neurotoxic effects of methamphetamine while methylone accentuates it. Neither MDPV nor methylone attenuates the hyperthermic effects of methamphetamine. The potent neuroprotective effects of MDPV extend to amphetamine-, 3,4-methylenedioxymethamphetamine-, and MPTP-induced neurotoxicity. These results indicate that β-ketoamphetamine drugs that are non-substrate blockers of the DA transporter (i.e., MDPV) protect against methamphetamine neurotoxicity, whereas those that are substrates for uptake by the DA transporter and which cause DA release (i.e., methylone, mephedrone) accentuate neurotoxicity. PMID:25626880

Oral sensory nerve damage: Causes and consequences.

PubMed

Snyder, Derek J; Bartoshuk, Linda M

2016-06-01

Oral sensations (i.e., taste, oral somatosensation, retronasal olfaction) are integrated into a composite sense of flavor, which guides dietary choices with long-term health impact. The nerves carrying this input are vulnerable to peripheral damage from multiple sources (e.g., otitis media, tonsillectomy, head injury), and this regional damage can boost sensations elsewhere in the mouth because of central interactions among nerve targets. Mutual inhibition governs this compensatory process, but individual differences lead to variation in whole-mouth outcomes: some individuals are unaffected, others experience severe loss, and some encounter sensory increases that may (if experienced early in life) elevate sweet-fat palatability and body mass. Phantom taste, touch, or pain sensations (e.g., burning mouth syndrome) may also occur, particularly in those expressing the most taste buds. To identify and treat these conditions effectively, emerging clinical tests measure regional vs. whole-mouth sensation, stimulated vs. phantom cues, and oral anatomy. Scaling methods allowing valid group comparisons have strongly aided these efforts. Overall, advances in measuring oral sensory function in health and disease show promise for understanding the varied clinical consequences of nerve damage.

Oral Sensory Nerve Damage: Causes and Consequences

PubMed Central

Snyder, Derek J.; Bartoshuk, Linda M.

2016-01-01

Oral sensations (i.e., taste, oral somatosensation, retronasal olfaction) are integrated into a composite sense of flavor, which guides dietary choices with long-term health impact. The nerves carrying this input are vulnerable to peripheral damage from multiple sources (e.g., otitis media, tonsillectomy, head injury), and this regional damage can boost sensations elsewhere in the mouth because of central interactions among nerve targets. Mutual inhibition governs this compensatory process, but individual differences lead to variation in whole-mouth outcomes: some individuals are unaffected, others experience severe loss, and some encounter sensory increases that may (if experienced early in life) elevate sweet-fat palatability and body mass. Phantom taste, touch, or pain sensations (e.g., burning mouth syndrome) may also occur, particularly in those expressing the most taste buds. To identify and treat these conditions effectively, emerging clinical tests measure regional vs. whole-mouth sensation, stimulated vs. phantom cues, and oral anatomy. Scaling methods allowing valid group comparisons have strongly aided these efforts. Overall, advances in measuring oral sensory function in health and disease show promise for understanding the varied clinical consequences of nerve damage. PMID:27511471

Microsurgical Decompression of Inferior Alveolar Nerve After Endodontic Treatment Complications.

PubMed

Bianchi, Bernardo; Ferri, Andrea; Varazzani, Andrea; Bergonzani, Michela; Sesenna, Enrico

2017-07-01

Iatrogenic injury in oral surgery is the most frequent cause of sensory disturbance in the distribution of the inferior alveolar nerve (IAN) and mental nerve.Inferior alveolar nerve damage can occur during third molar extraction, implant location, orthognathic surgery, preprosthetic surgery, salivary gland surgery, local anesthetic injections or during the resection of benign or malignant tumors.Injuries to the IAN can be caused also by endodontic treatment of mandibular molars and premolars when filling material is forced into the tooth and mandibular canal.The sensory disturbances that could follow a damage of the IAN could be hypoesthesia, dysesthesia, hyperesthesia, anesthesia, and sometimes a painful anesthesia that strike ipsilateral lower lip, chin, and teeth. These can undermine life quality by affecting speech, chewing, and social interaction.Treatment of these complications is sometimes difficult and could consist in observation or in surgical decompression of the involved nerve to relieve the patient's symptoms and improve sensory recovery. The most debated points are the timing of intervention and the effective role of decompression in clinical outcome-improvement.The purpose of this article is to show authors' experience with 2 patients treated with microsurgical nerve decompression to remove endodontic material from the mandibular canal and providing also a comprehensive review of the literature.

Unilateral Punctate Keratitis Secondary to Wallenberg Syndrome

PubMed Central

Boto, Ana; Del Hierro, Almudena; Capote, Maria; Noval, Susana; Garcia, Amanda; Santiago, Susana

2014-01-01

We studied three patients who developed left unilateral punctate keratitis after suffering left-sided Wallenberg Syndrome. A complex evolution occurred in two of them. In all cases, neurophysiological studies showed damage in the trigeminal sensory component at the bulbar level. Corneal involvement secondary to Wallenberg syndrome is a rare cause of unilateral superficial punctate keratitis. The loss of corneal sensitivity caused by trigeminal neuropathy leads to epithelial erosions that are frequently unobserved by the patient, resulting in a high risk of corneal-ulcer development with the possibility of superinfection. Neurophysiological studies can help to locate the anatomical level of damage at the ophthalmic branch of the trigeminal nerve, confirming the suspected etiology of stroke, and demonstrating that prior vascular involvement coincides with the location of trigeminal nerve damage. In some of these patients, oculofacial pain is a distinctive feature. PMID:24882965

Chemical Stockpile Disposal Program Final Programmatic Environmental Impact Statement Volume 3: Appendices A-S

DTIC Science & Technology

1988-01-01

nerve and blister agents evaluated in this appendix have been especially formulated to cause -major injuries or death to enemy forces in wartime...days. Hallucinations, particularly of visual type. Patients may exhibit selfdestructive acts l Seizures may occur, but true convulsions arc rare l Rare...lesions produced in experimental animals by GB and interprets the damage as caused by convulsions or seizure activity that kill neurons (nerve cells

Hazards of Improper Dispensary: Literature Review and Report of an Accidental Chloroform Injection.

PubMed

Verma, Prashant; Tordik, Patricia; Nosrat, Ali

2018-06-01

Several clear, transparent solutions are used in endodontics. Inappropriate dispensing methods can lead to accidental injection or accidental irrigation. These accidents can cause permanent tissue damage including damage to the bone, periodontium, nerves, and vasculature. This article reports on the consequences of an accidental chloroform injection. Nonsurgical retreatment of tooth #8 was planned as part of a restorative treatment plan in a 69-year-old woman. The dentist accidentally injected chloroform instead of local anesthesia because chloroform was loaded into the anesthetic syringe. The patient experienced severe pain and swelling and soft tissue necrosis and suffered permanent sensory and motor nerve damage. A review of the literature was performed on accidents caused by improper dispensary, namely accidental injections and accidental irrigations. The data were extracted and summarized. Sodium hypochlorite, chlorhexidine, formalin, formocresol, 1:1000 adrenaline, benzalkonium chloride, and lighter fuel were accidentally injected as an intraoral nerve block or as infiltration injections. Bone and soft tissue necrosis, tooth loss, and sensory nerve damage (anesthesia and paresthesia) were the most common consequences reported. Such disastrous events can be prevented by appropriate labeling and separate dispensing methods for each solution. There is a need for disseminating information on toxicity and biocompatibility of materials/solutions used in endodontics. The authors recommend training dental students and endodontic residents on immediate and long-term therapeutic management of patients when an accidental injection or accidental irrigation occurs. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Ear tube insertion

MedlinePlus

... eardrum may cause some hearing loss. But most children do not have long-term damage to their hearing or speech, even when the ... not go away with treatment, or if a child has many ear infections ... or that damages nearby nerves Injury to the ear after sudden ...

Avulsion of the brachial plexus in a great horned owl (Bubo virginaus)

USGS Publications Warehouse

Moore, M.P.; Stauber, E.; Thomas, N.J.

1989-01-01

Avulsion of the brachial plexus was documented in a Great Horned Owl (Bubo virginianus). A fractured scapula was also present. Cause of these injuries was not known but was thought to be due to trauma. Differentiation of musculoskeletal injury from peripheral nerve damage can be difficult in raptors. Use of electromyography and motor nerve conduction velocity was helpful in demonstrating peripheral nerve involvement. A brachial plexus avulsion was suspected on the basis of clinical signs, presence of electromyographic abnormalities in all muscles supplied by the nerves of the brachial plexus and absence of median-ulnar motor nerve conduction velocities.

Pudendal Nerve and Internal Pudendal Artery Damage May Contribute to Radiation-Induced Erectile Dysfunction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nolan, Michael W., E-mail: mwnolan@ncsu.edu; Department of Environmental and Radiologic Health Sciences, Colorado State University, Fort Collins, Colorado; Marolf, Angela J.

Purpose/Objectives: Erectile dysfunction is common after radiation therapy for prostate cancer; yet, the etiopathology of radiation-induced erectile dysfunction (RI-ED) remains poorly understood. A novel animal model was developed to study RI-ED, wherein stereotactic body radiation therapy (SBRT) was used to irradiate the prostate, neurovascular bundles (NVB), and penile bulb (PB) of dogs. The purpose was to describe vascular and neurogenic injuries after the irradiation of only the NVB or the PB, and after irradiation of all 3 sites (prostate, NVB, and PB) with varying doses of radiation. Methods and Materials: Dogs were treated with 50, 40, or 30 Gy to themore » prostate, NVB, and PB, or 50 Gy to either the NVB or the PB, by 5-fraction SBRT. Electrophysiologic studies of the pudendal nerve and bulbospongiosus muscles and ultrasound studies of pelvic perfusion were performed before and after SBRT. The results of these bioassays were correlated with histopathologic changes. Results: SBRT caused slowing of the systolic rise time, which corresponded to decreased arterial patency. Alterations in the response of the internal pudendal artery to vasoactive drugs were observed, wherein SBRT caused a paradoxical response to papaverine, slowing the systolic rise time after 40 and 50 Gy; these changes appeared to have some dose dependency. The neurofilament content of penile nerves was also decreased at high doses and was more profound when the PB was irradiated than when the NVB was irradiated. These findings are coincident with slowing of motor nerve conduction velocities in the pudendal nerve after SBRT. Conclusions: This is the first report in which prostatic irradiation was shown to cause morphologic arterial damage that was coincident with altered internal pudendal arterial tone, and in which decreased motor function in the pudendal nerve was attributed to axonal degeneration and loss. Further investigation of the role played by damage to these structures in RI-ED is warranted.« less

Wisdom tooth extraction causing lingual nerve and styloglossus muscle damage: a mimic of multiple cranial nerve palsies.

PubMed

Carr, Aisling S; Evans, Matthew; Shah, Sachit; Catania, Santi; Warren, Jason D; Gleeson, Michael J; Reilly, Mary M

2017-06-01

The combination of tongue hemianaesthesia, dysgeusia, dysarthria and dysphagia suggests the involvement of multiple cranial nerves. We present a case with sudden onset of these symptoms immediately following wisdom tooth extraction and highlight the clinical features that allowed localisation of the lesion to a focal, iatrogenic injury of the lingual nerve and adjacent styloglossus muscle. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

MK-801 and dextromethorphan block microglial activation and protect against methamphetamine-induced neurotoxicity.

PubMed

Thomas, David M; Kuhn, Donald M

2005-07-19

Methamphetamine causes long-term toxicity to dopamine nerve endings of the striatum. Evidence is emerging that microglia can contribute to the neuronal damage associated with disease, injury, or inflammation, but their role in methamphetamine-induced neurotoxicity has received relatively little attention. Lipopolysaccharide (LPS) and the neurotoxic HIV Tat protein, which cause dopamine neuronal toxicity after direct infusion into brain, cause activation of cultured mouse microglial cells as evidenced by increased expression of intracellular cyclooxygenase-2 and elevated secretion of tumor necrosis factor-alpha. MK-801, a non-competitive NMDA receptor antagonist that is known to protect against methamphetamine neurotoxicity, prevents microglial activation by LPS and HIV Tat. Dextromethorphan, an antitussive agent with NMDA receptor blocking properties, also prevents microglial activation. In vivo, MK-801 and dextromethorphan reduce methamphetamine-induced activation of microglia in striatum and they protect dopamine nerve endings against drug-induced nerve terminal damage. The present results indicate that the ability of MK-801 and dextromethorphan to protect against methamphetamine neurotoxicity is related to their common property as blockers of microglial activation.

Deoxycholic Acid and the Marginal Mandibular Nerve: A Cadaver Study.

PubMed

Blandford, Alexander D; Ansari, Waseem; Young, Jason M; Maley, Bruce; Plesec, Thomas P; Hwang, Catherine J; Perry, Julian D

2018-06-04

One of the rare but serious complications observed with deoxycholic acid administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve. A segment of marginal mandibular nerve was harvested from 12 hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 h, deoxycholic acid (10 mg/ml) for 20 min, or deoxycholic acid (10 mg/ml) for 24 h. The nerve specimens were then fixed in glutaraldehyde for a minimum of 24 h. Toluidine blue stained sections were evaluated for stain intensity using light microscopy and color deconvolution image analysis. Supraplatysmal fat was harvested as a positive control and exposed to the same treatments as the marginal mandibular nerve specimens, then evaluated using transmission electron microscopy. Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 h showed less toluidine blue staining than that of the nerve exposed to deoxycholic acid for 20 min. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte cell membrane integrity and loss of cellular organelles when compared to specimens only exposed to saline. Deoxycholic acid (10 mg/ml) damages the marginal mandibular nerve myelin sheath in fresh human cadaver specimens. Direct deoxycholic acid neurotoxicity may cause marginal mandibular nerve injury clinically. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Protection and Dissection of Recurrent Laryngeal Nerve in Salvage Thyroid Cancer Surgery to Patients with Insufficient Primary Operation Extent and Suspicious Residual Tumor.

PubMed

Yu, Wen-Bin; Zhang, Nai-Song

2015-01-01

Some thyroid cancer patients undergone insufficient tumor removal in the primary surgery in China . our aim is to evaluate the impact of dissection of the recurrent laryngeal nerve during a salvage thyroid cancer operation in these patients to prevent nerve injury. Clinical data of 49 enrolled patients who received a salvage thyroid operation were retrospectively reviewed. Primary pathology was thyroid papillary cancer. The initial procedure performed included nodulectomy (20 patients), partial thyroidectomy (19 patients) and subtotal thyroidectomy (10 patients). The effect of dissection and protection of the recurrent laryngeal nerve and the mechanism of nerve injury were studied. The cervical courses of the recurrent laryngeal nerves were successfully dissected in all cases. Nerves were adherent to or involved by scars in 22 cases. Three were ligated near the place where the nerve entered the larynx, while another three were cut near the intersection of inferior thyroid artery with the recurrent laryngeal nerve. Light hoarseness occurred to four patients without a preoperative voice change. In conclusion, accurate primary diagnosis allows for a sufficient primary operation to be performed, avoiding insufficient tumor removal that requires a secondary surgery. The most important cause of nerve damage resulted from not identifying the recurrent laryngeal nerve during first surgery , and meticulous dissection during salvage surgery was the most efficient method to avoid nerve damage.

Effect of high doses of 2-CdA on Schwann cells of mouse peripheral nerve.

PubMed

Djaldetti, R; Hart, J; Alexandrova, S; Cohen, S; Beilin, B; Djaldetti, M; Bessler, H

1996-07-01

The present study was undertaken to examine the effect of 2-CdA (Leustatin) on the Schwann cells of myelinated and unmyelinated fibers of peripheral mouse nerve. Two groups of mice were injected intravenously for seven days with 2-CdA: one group received daily doses of 1 mg/kg and the other 0.5 mg/kg. Both doses exceeded those accepted in clinical practice. Mice injected with saline served as controls. The sciatic nerve was then dissected and examined with a transmission electron microscope. The Schwann cells of both the myelinated and unmyelinated nerve fibers of the animals receiving the higher doses of 2-CdA showed nuclear and nucleolus damage, loss of heterochromatin, vacuolization and disorganization of the myelin sheaths. The mesaxons and the axons were also damaged. The Schwann cells of the animals treated with the lower doses appeared undamaged. The results indicate that in contrast to other anticancer drugs known to produce peripheral neuropathy, 2-CdA may cause damage to the Schwann cells only at doses exceeding the therapeutic ones.

Myelin

MedlinePlus

... and fatty substances. This myelin sheath allows electrical impulses to transmit quickly and efficiently along the nerve cells. If myelin is damaged, these impulses slow down. This can cause diseases such as ...

Biocompatible Electroactive Tetra(aniline)-Conjugated Peptide Nanofibers for Neural Differentiation.

PubMed

Arioz, Idil; Erol, Ozlem; Bakan, Gokhan; Dikecoglu, F Begum; Topal, Ahmet E; Urel, Mustafa; Dana, Aykutlu; Tekinay, Ayse B; Guler, Mustafa O

2018-01-10

Peripheral nerve injuries cause devastating problems for the quality of patients' lives, and regeneration following damage to the peripheral nervous system is limited depending on the degree of the damage. Use of nanobiomaterials can provide therapeutic approaches for the treatment of peripheral nerve injuries. Electroactive biomaterials, in particular, can provide a promising cure for the regeneration of nerve defects. Here, a supramolecular electroactive nanosystem with tetra(aniline) (TA)-containing peptide nanofibers was developed and utilized for nerve regeneration. Self-assembled TA-conjugated peptide nanofibers demonstrated electroactive behavior. The electroactive self-assembled peptide nanofibers formed a well-defined three-dimensional nanofiber network mimicking the extracellular matrix of the neuronal cells. Neurite outgrowth was improved on the electroactive TA nanofiber gels. The neural differentiation of PC-12 cells was more advanced on electroactive peptide nanofiber gels, and these biomaterials are promising for further use in therapeutic neural regeneration applications.

Rehabilitation of the trigeminal nerve

PubMed Central

Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

2005-01-01

When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

Temperature-controlled optical stimulation of the rat prostate cavernous nerves

NASA Astrophysics Data System (ADS)

Tozburun, Serhat; Hutchens, Thomas C.; McClain, Michael A.; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

2013-06-01

Optical nerve stimulation (ONS) may be useful as a diagnostic tool for intraoperative identification and preservation of the prostate cavernous nerves (CN), responsible for erectile function, during prostate cancer surgery. Successful ONS requires elevating the nerve temperature to within a narrow range (˜42 to 47°C) for nerve activation without thermal damage to the nerve. This preliminary study explores a prototype temperature-controlled optical nerve stimulation (TC-ONS) system for maintaining a constant (±1°C) nerve temperature during short-term ONS of the rat prostate CNs. A 150-mW, 1455-nm diode laser was operated in continuous-wave mode, with and without temperature control, during stimulation of the rat CNs for 15 to 30 s through a fiber optic probe with a 1-mm-diameter spot. A microcontroller opened and closed an in-line mechanical shutter in response to an infrared sensor, with a predetermined temperature set point. With TC-ONS, higher laser power settings were used to rapidly and safely elevate the CNs to a temperature necessary for a fast intracavernous pressure response, while also preventing excessive temperatures that would otherwise cause thermal damage to the nerve. With further development, TC-ONS may provide a rapid, stable, and safe method for intraoperative identification and preservation of the prostate CNs.

Immediate balloon deflation for prevention of persistent phrenic nerve palsy during pulmonary vein isolation by balloon cryoablation.

PubMed

Ghosh, Justin; Sepahpour, Ali; Chan, Kim H; Singarayar, Suresh; McGuire, Mark A

2013-05-01

Persistent phrenic nerve palsy is the most frequent complication of cryoballoon ablation for atrial fibrillation and can be disabling. To describe a technique-immediate balloon deflation (IBD)-for the prevention of persistent phrenic nerve palsy, provide data for its use, and describe in vitro simulations performed to investigate the effect of IBD on the atrium and pulmonary vein. Cryoballoon procedures for atrial fibrillation were analyzed retrospectively (n = 130). IBD was performed in patients developing phrenic nerve dysfunction (n = 22). In vitro simulations were performed by using phantoms. No adverse events occurred, and all patients recovered normal phrenic nerve function before leaving the procedure room. No patient developed persistent phrenic nerve palsy. The mean cryoablation time to onset of phrenic nerve dysfunction was 144 ± 64 seconds. Transient phrenic nerve dysfunction was seen more frequently with the 23-mm balloon than with the 28-mm balloon (11 of 39 cases vs 11 of 81 cases; P = .036). Balloon rewarming was faster following IBD. The time to return to 0 and 20° C was shorter in the IBD group (6.7 vs 8.9 seconds; P = .007 and 16.7 vs 37.6 seconds; P<.0001). In vitro simulations confirmed that IBD caused more rapid tissue warming (time to 0°C, 14.0 ± 3.4 seconds vs 46.0 ± 8.1; P = .0001) and is unlikely to damage the atrium or pulmonary vein. IBD results in more rapid tissue rewarming, causes no adverse events, and appears to prevent persistent phrenic nerve palsy. Simulations suggest that IBD is unlikely to damage the atrium or pulmonary vein. Copyright © 2013 Heart Rhythm Society. All rights reserved.

Electronystagmography

MedlinePlus

... movements. Any disease or injury that damages the acoustic nerve can cause vertigo. This may include: Blood ... conditions under which the test may be performed: Acoustic neuroma Benign positional vertigo Labyrinthitis Meniere disease

Tapentadol

MedlinePlus

... the cause of the pain is healed). Tapentadol extended-release tablets are used to treat severe neuropathic ... nerve damage) in people who have diabetes. Tapentadol extended-release tablets are only used to treat people ...

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

PubMed

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.

Sound damage and gentamicin treatment produce different patterns of damage to the efferent innervation of the chick cochlea.

PubMed

Ofsie, M S; Hennig, A K; Messana, E P; Cotanche, D A

1997-11-01

Both sound exposure and gentamicin treatment cause damage to sensory hair cells in the peripheral chick auditory organ, the basilar papilla. This induces a regeneration response which replaces hair cells and restores auditory function. Since functional recovery requires the re-establishment of connections between regenerated hair cells and the central nervous system, we have investigated the effects of sound damage and gentamicin treatment on the neuronal elements within the cochlea. Whole-mount preparations of basilar papillae were labeled with phalloidin to label the actin cytoskeleton and antibodies to neurofilaments, choline acetyltransferase, and synapsin to label neurons; and examined by confocal laser scanning microscopy. When chicks are treated with gentamicin or exposed to acoustic overstimulation, the transverse nerve fibers show no changes from normal cochleae assayed in parallel. Efferent nerve terminals, however, disappear from areas depleted of hair cells following acoustic trauma. In contrast, efferent nerve endings are still present in the areas of hair cell loss following gentamicin treatment, although their morphological appearance is greatly altered. These differences in the response of efferent nerve terminals to sound exposure versus gentamicin treatment may account, at least in part, for the discrepancies reported in the time of recovery of auditory function.

Femoral nerve damage (image)

MedlinePlus

The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

Different dose-dependent effects of ebselen in sciatic nerve ischemia-reperfusion injury in rats.

PubMed

Ozyigit, Filiz; Kucuk, Aysegul; Akcer, Sezer; Tosun, Murat; Kocak, Fatma Emel; Kocak, Cengiz; Kocak, Ahmet; Metineren, Hasan; Genc, Osman

2015-08-26

Ebselen is an organoselenium compound which has strong antioxidant and anti-inflammatory effects. We investigated the neuroprotective role of ebselen pretreatment in rats with experimental sciatic nerve ischemia-reperfusion (I/R) injury. Adult male Sprague Dawley rats were divided into four groups (N = 7 in each group). Before sciatic nerve I/R was induced, ebselen was injected intraperitoneally at doses of 15 and 30 mg/kg. After a 2 h ischemia and a 3 h reperfusion period, sciatic nerve tissues were excised. Tissue levels of malondialdehyde (MDA) and nitric oxide (NO), and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were measured. Sciatic nerve tissues were also examined histopathologically. The 15 mg/kg dose of ebselen reduced sciatic nerve damage and apoptosis (p<0.01), levels of MDA, NO, and inducible nitric oxide synthase (iNOS) positive cells (p<0.01, p<0.05, respectively), and increased SOD, GPx, and CAT activities (p<0.001, p<0.01, p<0.05, respectively) compared with the I/R group that did not receive ebselen. Conversely, the 30 mg/kg dose of ebselen increased sciatic nerve damage, apoptosis, iNOS positive cells (p<0.01, p<0.05, p<0.001) and MDA and NO levels (p<0.05, p<0.01) and decreased SOD, GPx, and CAT activities (p<0.05) compared with the sham group. The results of this study suggest that ebselen may cause different effects depending on the dose employed. Ebselen may be protective against sciatic nerve I/R injury via antioxidant and antiapoptotic activities at a 15 mg/kg dose, conversely higher doses may cause detrimental effects.

Pressure wave injuries to the nervous system caused by high-energy missile extremity impact: Part I. Local and distant effects on the peripheral nervous system--a light and electron microscopic study on pigs.

PubMed

Suneson, A; Hansson, H A; Seeman, T

1990-03-01

Pigs were used for studies of effects on the peripheral nervous tissue of pressure waves induced by impact and passage through the left thigh of high-energy missiles. The short-lasting pressure waves were demonstrated to move close to the speed of sound and to have a spectrum of high frequencies and large amplitudes. The sciatic nerve in the contralateral leg showed no hemorrhage or major deformation. Both immediately after the missile impact and after 48 hr the myelin sheaths in the contralateral sciatic nerve showed deformation. Myelin was bulging into the axon, dislocating the axoplasm. The nodes of Ranvier could be exposed to an increased extent. Electron microscopic examination revealed decreased number of microtubules immediately after the trauma, persisting even after 48 hr in the largest axon. Schwann cells showed, especially after 48 hr, signs of damage and swelling. Similar changes, although less extensive, were noticed in the phrenic nerves as well as in unmyelinated axons in both sciatic and phrenic nerves. It is concluded that a high-energy missile hit in the thigh of a pig, caused structurally demonstrable dislocations of myelin sheaths, and disarrangement of cytoskeleton and endoplasmic reticulum in axons as well as other signs of damage. The changes may interfere with the normal functions of peripheral and autonomic nerves.

Laser Phototherapy As Modality of Clinical Treatment in Bell's Palsy

NASA Astrophysics Data System (ADS)

Marques, A. M. C.; Soares, L. G. P.; Marques, R. C.; Pinheiro, A. L. B.; Dent, M.

2011-08-01

Bell's palsy is defined as a peripheral facial nerve palsy, idiophatic, and sudden onset and is considered the most common cause of this pathology. It is caused by damage to cranial nerves VII, resulting in complete or partial paralysis of the facial mimic. May be associated with taste disturbances, salivation, tearing and hyperacusis. It is diagnosed after ruling out all possible etiologies, because its cause is not fully understood.Some researches shows that herpes virus may cause this type of palsy due to reactivation of the virus or by imunnomediated post-viral nerve demielinization. Physical therapy, corticosteroids and antiviral therapy have become the most widely accepted treatments for Bell's palsy. Therapy with low-level laser (LLLT) may induce the metabolism of injured nerve tissue for the production of proteins associated with its growth and to improve nerve regeneration. The success of the treatment of Bell's palsy by using laser phototherapy isolated or in association with other therapeutic approach has been reported on the literature. In most cases, the recovery occurs without uneventfully (complications), the acute illness is not associated with serious disorders. We will present a clinical approach for treating this condition.

Reduced 3,4-Methylenedioxymethamphetamine (MDMA, Ecstasy)-Initiated Oxidative DNA Damage and Neurodegeneration in Prostaglandin H Synthase-1 Knockout Mice

PubMed Central

2010-01-01

The neurodegenerative potential of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) and underlying mechanisms are under debate. Here, we show that MDMA is a substrate for CNS prostaglandin H synthase (PHS)-catalyzed bioactivation to a free radical intermediate that causes reactive oxygen species (ROS) formation and neurodegenerative oxidative DNA damage. In vitro PHS-1-catalyzed bioactivation of MDMA stereoselectively produced free radical intermediate formation and oxidative DNA damage that was blocked by the PHS inhibitor eicosatetraynoic acid. In vivo, MDMA stereoselectively caused gender-independent DNA oxidation and dopaminergic nerve terminal degeneration in several brain regions, dependent on regional PHS-1 levels. Conversely, MDMA-initiated striatal DNA oxidation, nerve terminal degeneration, and motor coordination deficits were reduced in PHS-1 +/− and −/− knockout mice in a gene dose-dependent fashion. These results confirm the neurodegenerative potential of MDMA and provide the first direct evidence for a novel molecular mechanism involving PHS-catalyzed formation of a neurotoxic MDMA free radical intermediate. PMID:22778832

Neurotrophic factors and corneal nerve regeneration

PubMed Central

Sacchetti, Marta; Lambiase, Alessandro

2017-01-01

The cornea has unique features that make it a useful model for regenerative medicine studies. It is an avascular, transparent, densely innervated tissue and any pathological changes can be easily detected by slit lamp examination. Corneal sensitivity is provided by the ophthalmic branch of the trigeminal nerve that elicits protective reflexes such as blinking and tearing and exerts trophic support by releasing neuromediators and growth factors. Corneal nerves are easily evaluated for both function and morphology using standard instruments such as corneal esthesiometer and in vivo confocal microscope. All local and systemic conditions that are associated with damage of the trigeminal nerve cause the development of neurotrophic keratitis, a rare degenerative disease. Neurotrophic keratitis is characterized by impairment of corneal sensitivity associated with development of persistent epithelial defects that may progress to corneal ulcer, melting and perforation. Current neurotrophic keratitis treatments aim at supporting corneal healing and preventing progression of corneal damage. Novel compounds able to stimulate corneal nerve recovery are in advanced development stage. Among them, nerve growth factor eye drops showed to be safe and effective in stimulating corneal healing and improving corneal sensitivity in patients with neurotrophic keratitis. Neurotrophic keratitis represents an useful model to evaluate in clinical practice novel neuro-regenerative drugs. PMID:28966630

[Damage to cranial and peripheral nerves following patency restoration of the internal carotid artery].

PubMed

Myrcha, P; Ciostek, P; Szopiński, P; Noszczyk, W

2001-01-01

The aim of the study was an assessment of the incidence of injury to cranial and peripheral nerves as complication of patency restoration of the internal carotid artery, and analysis of the effect of peripheral nerve injury on the results of carotid patency restoration. From Oct 1987 to Sept 1999 543 procedures were carried out for restoration of patency of the internal carotid artery. After the operation hypoglossus nerve injury was found in 7 cases (1.4%), vagus injury in 9 (1.8%). Signs of exclusively recurrent laryngeal nerve damage were found in 6 cases (1.2%). Glossopharyngeus nerve was damaged in 2 cases (0.4%), transient phrenic nerve palsy as a result of conduction anaesthesia was noted in 2 cases (0.4%). Damage to the transverse cervical nerve was found in 96 cases (60%). In 2 patients (1.2%) lower position of mouth angle was due to section of the mandibular ramus of the facial nerve. In another 2 cases skin sensation disturbances were a consequence of lesion of the auricularis magnus nerve and always they coexisted with signs of transverse cervical nerve damage. damage to the cranial nerves during operation for carotid patency restoration are frequent but mostly they are not connected with any health risks and often they regress spontaneously.

Wernicke-Korsakoff syndrome

MedlinePlus

... cause leg tremor Vision changes such as abnormal eye movements (back and forth movements called nystagmus), double vision , ... may show damage to many nerve systems: Abnormal eye movement Decreased or abnormal reflexes Fast pulse (heart rate) ...

Nucleus Accumbens Invulnerability to Methamphetamine Neurotoxicity

PubMed Central

Kuhn, Donald M.; Angoa-Pérez, Mariana; Thomas, David M.

2016-01-01

Methamphetamine (Meth) is a neurotoxic drug of abuse that damages neurons and nerve endings throughout the central nervous system. Emerging studies of human Meth addicts using both postmortem analyses of brain tissue and noninvasive imaging studies of intact brains have confirmed that Meth causes persistent structural abnormalities. Animal and human studies have also defined a number of significant functional problems and comorbid psychiatric disorders associated with long-term Meth abuse. This review summarizes the salient features of Meth-induced neurotoxicity with a focus on the dopamine (DA) neuronal system. DA nerve endings in the caudate-putamen (CPu) are damaged by Meth in a highly delimited manner. Even within the CPu, damage is remarkably heterogeneous, with ventral and lateral aspects showing the greatest deficits. The nucleus accumbens (NAc) is largely spared the damage that accompanies binge Meth intoxication, but relatively subtle changes in the disposition of DA in its nerve endings can lead to dramatic increases in Meth-induced toxicity in the CPu and overcome the normal resistance of the NAc to damage. In contrast to the CPu, where DA neuronal deficiencies are persistent, alterations in the NAc show a partial recovery. Animal models have been indispensable in studies of the causes and consequences of Meth neurotoxicity and in the development of new therapies. This research has shown that increases in cytoplasmic DA dramatically broaden the neurotoxic profile of Meth to include brain structures not normally targeted for damage. The resistance of the NAc to Meth-induced neurotoxicity and its ability to recover reveal a fundamentally different neuroplasticity by comparison to the CPu. Recruitment of the NAc as a target of Meth neurotoxicity by alterations in DA homeostasis is significant in light of the numerous important roles played by this brain structure. PMID:23382149

Nucleus accumbens invulnerability to methamphetamine neurotoxicity.

PubMed

Kuhn, Donald M; Angoa-Pérez, Mariana; Thomas, David M

2011-01-01

Methamphetamine (Meth) is a neurotoxic drug of abuse that damages neurons and nerve endings throughout the central nervous system. Emerging studies of human Meth addicts using both postmortem analyses of brain tissue and noninvasive imaging studies of intact brains have confirmed that Meth causes persistent structural abnormalities. Animal and human studies have also defined a number of significant functional problems and comorbid psychiatric disorders associated with long-term Meth abuse. This review summarizes the salient features of Meth-induced neurotoxicity with a focus on the dopamine (DA) neuronal system. DA nerve endings in the caudate-putamen (CPu) are damaged by Meth in a highly delimited manner. Even within the CPu, damage is remarkably heterogeneous, with ventral and lateral aspects showing the greatest deficits. The nucleus accumbens (NAc) is largely spared the damage that accompanies binge Meth intoxication, but relatively subtle changes in the disposition of DA in its nerve endings can lead to dramatic increases in Meth-induced toxicity in the CPu and overcome the normal resistance of the NAc to damage. In contrast to the CPu, where DA neuronal deficiencies are persistent, alterations in the NAc show a partial recovery. Animal models have been indispensable in studies of the causes and consequences of Meth neurotoxicity and in the development of new therapies. This research has shown that increases in cytoplasmic DA dramatically broaden the neurotoxic profile of Meth to include brain structures not normally targeted for damage. The resistance of the NAc to Meth-induced neurotoxicity and its ability to recover reveal a fundamentally different neuroplasticity by comparison to the CPu. Recruitment of the NAc as a target of Meth neurotoxicity by alterations in DA homeostasis is significant in light of the numerous important roles played by this brain structure.

Traction injury of the recurrent laryngeal nerve: Results of continuous intraoperative neuromonitoring in a swine model.

PubMed

Lee, Hye Yoon; Cho, Young Geon; You, Ji Young; Choi, Byoung Ho; Kim, Joon Yub; Wu, Che-Wei; Chiang, Feng-Yu; Kim, Hoon Yub

2016-04-01

Recurrent laryngeal nerve (RLN) palsy is the most serious complication after thyroidectomy. However, little is known about the degree of traction injury that causes loss of signal. The purpose of this study was to evaluate traction injuries in the swine RLN using continuous intraoperative neuromonitoring (IONM) and determine the traction power that results in loss of signal. Thirteen swine underwent traction injury to the RLNs with continuous IONM, and stress-strain curves were determined for 8 nerves using the universal material testing machine in an ex vivo model. Traction injury at a mean power of 2.83 MPa caused loss of signal. The mean physiologic limit strain and tensile strength of the swine RLNs were found to be 15.0% and 4.9 MPa, respectively. Histological analysis showed no abnormal structural findings. Traction injury of swine RLNs causes loss of signal at a power of 2.83 MPa. However, all injured nerves recovered within 7 days with no observed structural damage. © 2015 Wiley Periodicals, Inc.

Rehabilitation of Bell's palsy patient with complete dentures.

PubMed

Muthuvignesh, J; Kumar, N Suman; Reddy, D Narayana; Rathinavelu, Pradeep; Egammai, S; Adarsh, A

2015-08-01

Facial nerve disorders may be of sudden onset and more often of unknown etiology. Edema of the facial nerve within the fallopian canal results in Bell's palsy. This causes compression of the nerve and affects the microcirculation. Many authors have suggested treatment for facial nerve paralysis ranging from simple physiotherapy to complicated microvascular decompression. It more often results in symptoms like synkinesis and muscle spasm after the decompression surgery of the nerve because of the inability to arrange the nerve fibers within the canal. The treatment choice also depends on patient's age, extent of the nerve damage, and patient's needs and desires. Many patients who cannot be rehabilitated functionally can be treated for esthetics of the involved muscles. This case report elaborates about a patient who was rehabilitated for esthetics and to some extent for function.

Ramsay Hunt syndrome with unilateral polyneuropathy involving cranial nerves V, VII, VIII, and XII in a diabetic patient.

PubMed

Sun, Wei-Lian; Yan, Jian-Liang; Chen, Li-Li

2011-01-01

Ramsay Hunt syndrome is a rare complication of the varicella zoster virus, defined as a peripheral facial palsy that typically results from involvement of the facial and auditory nerves. Ramsay Hunt syndrome can be associated with cranial nerves V, VI, IX, and X but rarely with XII. We describe an atypical case of Ramsay Hunt syndrome with multiple cranial nerve involvement of nerves V, VII, VIII, and XII. Antiviral drugs, antibiotics, insulin, and traditional Chinese drugs were administered immediately after admission. After 3 months of combination therapy, the patient had recovered satisfactorily. Herpes zoster can cause severe infections in diabetic patients and should be treated as soon after detection as possible. Ramsay Hunt syndrome should be recognized as a polycranial neuritis characterized by damage to sensory and motor nerves. In addition to facial and vestibular nerve paralysis, Ramsay Hunt syndrome may also involve cranial nerves V and XII.

Winged Scapula: A Comprehensive Review of Surgical Treatment

PubMed Central

Charran, Ordessia; Yilmaz, Emre; Edwards, Bryan; Muhleman, Mitchel A; Oskouian, Rod J; Tubbs, R. Shane; Loukas, Marios

2017-01-01

Winged scapula is caused by paralysis of the serratus anterior or trapezius muscles due to damage to the long thoracic or accessory nerves, resulting in loss of strength and range of motion of the shoulder. Because this nerve damage can happen in a variety of ways, initial diagnosis may be overlooked. This paper discusses the anatomical structures involved in several variations of winged scapula, the pathogenesis of winged scapula, and several historical and contemporary surgical procedures used to treat this condition. Additionally, this review builds upon the conclusions of several studies in order to suggest areas for continued research regarding the treatment of winged scapula. PMID:29456903

Relating retinal nerve fiber thickness to behavioral sensitivity in patients with glaucoma: application of a linear model.

PubMed

Hood, Donald C

2007-05-01

Glaucoma causes damage to the retinal ganglion cells and their axons, and this damage can be detected with both structural and functional tests. The purpose of this study was to better understand the relationship between a structural measure of retinal nerve fiber layer (RNFL) and the most common functional test, behavioral sensitivity with static automated perimetry (SAP). First, a linear model, previously shown to describe the relationship between local visual evoked potentials and SAP sensitivity, was modified to predict the change in RNFL as measured by optical coherence tomography. Second, previous work by others was shown to be consistent with this model.

Direct Conversion of Human Fibroblasts into Schwann Cells that Facilitate Regeneration of Injured Peripheral Nerve In Vivo

PubMed Central

Sowa, Yoshihiro; Kishida, Tsunao; Tomita, Koichi; Yamamoto, Kenta; Numajiri, Toshiaki

2017-01-01

Abstract Schwann cells (SCs) play pivotal roles in the maintenance and regeneration of the peripheral nervous system. Although transplantation of SCs enhances repair of experimentally damaged peripheral and central nerve tissues, it is difficult to prepare a sufficient number of functional SCs for transplantation therapy without causing adverse events for the donor. Here, we generated functional SCs by somatic cell reprogramming procedures and demonstrated their capability to promote peripheral nerve regeneration. Normal human fibroblasts were phenotypically converted into SCs by transducing SOX10 and Krox20 genes followed by culturing for 10 days resulting in approximately 43% directly converted Schwann cells (dSCs). The dSCs expressed SC‐specific proteins, secreted neurotrophic factors, and induced neuronal cells to extend neurites. The dSCs also displayed myelin‐forming capability both in vitro and in vivo. Moreover, transplantation of the dSCs into the transected sciatic nerve in mice resulted in significantly accelerated regeneration of the nerve and in improved motor function at a level comparable to that with transplantation of the SCs obtained from a peripheral nerve. The dSCs induced by our procedure may be applicable for novel regeneration therapy for not only peripheral nerve injury but also for central nerve damage and for neurodegenerative disorders related to SC dysfunction. Stem Cells Translational Medicine 2017;6:1207–1216 PMID:28186702

Nerve damage from diabetes - self-care

MedlinePlus

... this page: //medlineplus.gov/ency/patientinstructions/000326.htm Nerve damage from diabetes - self-care To use the ... or at other unusual times. Treating and Preventing Nerve Damage from Diabetes Treating diabetic neuropathy can make ...

Case of fibrolipomatous hamartoma of the digital nerve without macrodactyly.

PubMed

Nanno, Mitsuhiko; Sawaizumi, Takuya; Takai, Shinro

2011-01-01

Fibrolipomatous hamartoma of nerves without macrodactyly is a rare lesion characterized by fibrofatty proliferation causing epineural and perineural fibrosis with fatty infiltration around the nerve bundles. We report an unusual case of fibromatous hamartoma of the ulnar digital nerve of the thumb in a 43-year-old woman. Magnetic resonance imaging revealed a large fusiform mass along the nerve. The findings were unusual and pathognomonic and included a coaxial cable-like appearance on axial sections and a spaghettilike appearance on coronal sections on both T1- and T2-weighted images; these findings were useful for the diagnosis and preoperative evaluation of this lesion. Surgical exploration revealed a yellow, cordlike mass of the digital nerve enlarged by fat. Gross excision could not be done without extensive damage to the nerve. Therefore, a limited excision with biopsy of the fibrolipomatous tissue around the nerve bundles was performed. The histological appearance was consistent with fibrolipomatous hamartoma. There was no recurrence of the mass and no neurological deficit 3 years after surgery. Some authors have suggested that invasive excision can cause catastrophic sensory or motor deficits because of the extensive fatty infiltration of the nerve fascicles. In conclusion, the recommended treatment for this lesion is limited excision with only biopsy to confirm the diagnosis.

Diabetic Complications and Amputation Prevention

MedlinePlus

... because of two complications of diabetes: nerve damage (neuropathy) and poor circulation. Neuropathy causes loss of feeling in your feet, taking ... to the bone. Because of poor circulation and neuropathy in the feet, cuts or blisters can easily ...

Nerve damage assessment following implant placement in human cadaver jaws: an ex vivo comparative study.

PubMed

Murat, Sema; Kamburoğlu, Kıvanç; Kılıç, Cenk; Ozen, Tuncer; Gurbuz, Ayhan

2014-02-01

The present study compared the use of cone beam computerized tomography (CBCT) images and intra-oral radiographs in the placement of final implant drills in terms of nerve damage to cadaver mandibles. Twelve cadaver hemimandibles obtained from 6 cadavers were used. Right hemimandibles were imaged using peri-apical radiography and left hemimandibles using CBCT, and the images obtained were used in treatment planning for the placement of implant drills (22 for each modality, for a total of 44 final drills). Specimens were dissected, and the distances between the apex of the final implant drill and the inferior alveolar neurovascular bundle and incisive nerve were measured using a digital calliper. Nerves were assessed as damaged or not damaged, and the Chi-square test was used to compare nerve damage between modalities (P < 0.05). Nerve damage occurred with 7 final drills placed based on peri-apical radiography (31.8%) and 1 final drill placed using CBCT images (4.5%). The difference in nerve damage between imaging modalities was statistically significant (P = 0.023), with CBCT outperforming intraoral film in the placement of final implant drills ex vivo. In order to prevent nerve damage, CBCT is recommended as the principal imaging modality for pre-implant assessment.

Sciatic endometriosis induces mechanical hypersensitivity, segmental nerve damage, and robust local inflammation in rats

PubMed Central

Chen, S.; Xie, W.; Strong, J. A.; Jiang, J.; Zhang, J.-M.

2015-01-01

Background Endometriosis is a common cause of pain including radicular pain. Ectopic endometrial tissue may directly affect peripheral nerves including the sciatic, which has not been modelled in animals. Methods We developed a rat model for sciatic endometriosis by grafting a piece of autologous uterine tissue around the sciatic nerve. Control animals underwent a similar surgery but received a graft of pelvic fat tissue. Results The uterine grafts survived and developed fluid filled cysts; the adjacent nerve showed signs of swelling and damage. Mechanical and cold hypersensitivity and allodynia of the ipsilateral hindpaw developed gradually over the first two weeks after the surgery, peaked at 2 to 5 weeks, and was almost resolved by 7 weeks. Control animals showed only minor changes in these pain behaviors. Histological signs of inflammation in the uterine graft and in the adjacent nerve were observed at 3 weeks but were resolving by 7 weeks. In vivo fiber recording showed increased spontaneous activity, especially of C fibers, in sciatic nerve proximal to the uterine graft. Several pro-inflammatory cytokines including interluekin-18, VEGF, fractalkine, and MIP-1α, were elevated in the uterine graft plus sciatic nerve samples, compared to samples from normal nerve or nerve plus fat graft. Growth associated protein 43 (GAP43), a marker of regenerating nerve fibers, was observed in the adjacent sciatic nerve as well as in the uterine graft. Conclusions This model shared many features with other rat models of endometriosis, but also had some unique features more closely related to neuropathic pain models. PMID:26688332

Raman spectroscopy of non-penetrating peripheral nerve damage in swine: a tool for spectral pathology of nerves

NASA Astrophysics Data System (ADS)

Cilwa, Katherine E.; Slaughter, Tiffani; Elster, Eric A.; Forsberg, Jonathan A.; Crane, Nicole J.

2015-03-01

Over 30% of combat injuries involve peripheral nerve injury compared to only 3% in civilian trauma. In fact, nerve dysfunction is the second leading cause of long-term disability in injured service members and is present in 37% of upper limb injuries with disability. Identification and assessment of non-penetrating nerve injury in trauma patients could improve outcome and aid in therapeutic monitoring. We report the use of Raman spectroscopy as a noninvasive, non-destructive method for detection of nerve degeneration in intact nerves due to non-penetrating trauma. Nerve trauma was induced via compression and ischemia/reperfusion injury using a combat relevant swine tourniquet model (>3 hours ischemia). Control animals did not undergo compression/ischemia. Seven days post-operatively, sciatic and femoral nerves were harvested and fixed in formalin. Raman spectra of intact, peripheral nerves were collected using a fiber-optic probe with 3 mm diameter spot size and 785 nm excitation. Data was preprocessed, including fluorescence background subtraction, and Raman spectroscopic metrics were determined using custom peak fitting MATLAB scripts. The abilities of bivariate and multivariate analysis methods to predict tissue state based on Raman spectroscopic metrics are compared. Injured nerves exhibited changes in Raman metrics indicative of 45% decreased myelin content and structural damage (p<<0.01). Axonal and myelin degeneration, cell death and digestion, and inflammation of nerve tissue samples were confirmed via histology. This study demonstrates the non-invasive ability of Raman spectroscopy to detect nerve degeneration associated with non-penetrating injury, relevant to neurapraxic and axonotmetic injuries; future experiments will further explore the clinical utility of Raman spectroscopy to recognize neural injury.

Nerve trauma of the lower extremity: evaluation of 60,422 leg injured patients from the TraumaRegister DGU® between 2002 and 2015.

PubMed

Huckhagel, Torge; Nüchtern, Jakob; Regelsberger, Jan; Gelderblom, Mathias; Lefering, Rolf

2018-05-15

Nerve lesions are well known reasons for reduced functional capacity and diminished quality of life. By now only a few epidemiological studies focus on lower extremity trauma related nerve injuries. This study reveals frequency and characteristics of nerve damages in patients with leg trauma in the European context. Sixty thousand four hundred twenty-two significant limb trauma cases were derived from the TraumaRegister DGU® between 2002 and 2015. The TR-DGU is a multi- centre database of severely injured patients. We compared patients with additional nerve injury to those with intact neural structures for demographic data, trauma mechanisms, concomitant injuries, treatment and outcome parameters. Approximately 1,8% of patients with injured lower extremities suffer from additional nerve trauma. These patients were younger (mean age 38,1 y) and more likely of male sex (80%) compared to the patients without nerve injury (mean age 46,7 y; 68,4% male). This study suggests the peroneal nerve to be the most frequently involved neural structure (50,9%). Patients with concomitant nerve lesions generally required a longer hospital stay and exhibited a higher rate for subsequent rehabilitation. Peripheral nerve damage was mainly a consequence of motorbike (31,2%) and car accidents (30,7%), whereas leg trauma without nerve lesion most frequently resulted from car collisions (29,6%) and falls (29,8%). Despite of its low frequency nerve injury remains a main cause for reduced functional capacity and induces high socioeconomic expenditures due to prolonged rehabilitation and absenteeism of the mostly young trauma victims. Further research is necessary to get insight into management and long term outcome of peripheral nerve injuries.

A novel single compartment in vitro model for electrophysiological research using the perfluorocarbon FC-770.

PubMed

Choudhary, M; Clavica, F; van Mastrigt, R; van Asselt, E

2016-06-20

Electrophysiological studies of whole organ systems in vitro often require measurement of nerve activity and/or stimulation of the organ via the associated nerves. Currently two-compartment setups are used for such studies. These setups are complicated and require two fluids in two separate compartments and stretching the nerve across one chamber to the other, which may damage the nerves. We aimed at developing a simple single compartment setup by testing the electrophysiological properties of FC-770 (a perfluorocarbon) for in vitro recording of bladder afferent nerve activity and electrical stimulation of the bladder. Perflurocarbons are especially suitable for such a setup because of their high oxygen carrying capacity and insulating properties. In male Wistar rats, afferent nerve activity was recorded from postganglionic branches of the pelvic nerve in vitro, in situ and in vivo. The bladder was stimulated electrically via the efferent nerves. Organ viability was monitored by recording spontaneous contractions of the bladder. Additionally, histological examinations were done to test the effect of FC-770 on the bladder tissue. Afferent nerve activity was successfully recorded in a total of 11 rats. The bladders were stimulated electrically and high amplitude contractions were evoked. Histological examinations and monitoring of spontaneous contractions showed that FC-770 maintained organ viability and did not cause damage to the tissue. We have shown that FC-770 enables a simple, one compartment in vitro alternative for the generally used two compartment setups for whole organ electrophysiological studies.

Transtympanic Facial Nerve Paralysis: A Review of the Literature

PubMed Central

Schaefer, Nathan; O’Donohue, Peter; French, Heath; Griffin, Aaron; Gochee, Peter

2015-01-01

Summary: Facial nerve paralysis because of penetrating trauma through the external auditory canal is extremely rare, with a paucity of published literature. The objective of this study is to review the literature on transtympanic facial nerve paralysis and increase physician awareness of this uncommon injury through discussion of its clinical presentation, management and prognosis. We also aim to improve patient outcomes in those that have sustained this type of injury by suggesting an optimal management plan. In this case report, we present the case of a 46-year-old white woman who sustained a unilateral facial nerve paresis because of a garfish penetrating her tympanic membrane and causing direct damage to the tympanic portion of her facial nerve. On follow-up after 12 months, her facial nerve function has largely returned to normal. Transtympanic facial nerve paralysis is a rare injury but can have a favorable prognosis if managed effectively. PMID:26090278

The Limitations of Diazepam as a Treatment for Nerve Agent-Induced Seizures and Neuropathology in Rats: Comparison with UBP302

DTIC Science & Technology

2014-11-01

to nerve agents induces prolonged status epilepticus (SE), causing brain damage or death. Diazepam (DZP) is the cur- rent US Food and Drug... status epilepticus (SE), which are initiated by the excessive stimulation of cholinergic receptors. If immediate death is prevented by adequate...5-yl)ethyl] decahydroisoquinoline-3-carboxylic acid; PBS, phosphate-buffered saline; SE, status epilepticus ; UBP302, (S)-3-(2-carboxybenzyl

Coronectomy of impacted mandibular third molars: A meta-analysis and systematic review of the literature

PubMed Central

Cervera-Espert*, Juan; Pérez-Martínez*, Sara; Cervera-Ballester, Juan; Penarrocha-Oltra, David

2016-01-01

Background Coronectomy is an alternative to complete removal of an impacted mandibular third molar. Most authors have recommended coronectomy to prevent damage to the inferior alveolar nerve during surgical extraction of lower third molars. The present study offers a systematic review and metaanalysis of the coronectomy technique. Material and Methods A systematic review and meta-analysis was performed based on a PubMed and Cochrane databases search for articles published from 2014 and involving coronectomy of mandibular third molars located near the inferior alveolar nerve canal, with a minimum of 10 cases and a minimum follow-up period of 6 months. After application of the inclusion and exclusion criteria, a total of 12 articles were included in the study. Results and Discussion Coronectomy results in significantly lesser loss of sensitivity of the inferior alveolar nerve and prevents the occurrence of dry socket. No statistically significant differences were observed in the incidence of pain and infection between coronectomy and complete surgical extraction. After coronectomy, the remaining tooth fragment migrates an average of 2 mm within two years. Conclusions Coronectomy is indicated when the mandibular third molar is in contact with the inferior alveolar nerve and complete removal of the tooth may cause nerve damage. Key words:Coronectomy, included third molar, inferior alveolar nerve injury. PMID:27031064

Chronic ankle instability and common fibular nerve injury.

PubMed

Benchortane, Michaël; Collado, Hervé; Coudreuse, Jean-Marie; Desnuelle, Claude; Viton, Jean-Michel; Delarque, Alain

2011-03-01

The lateral collateral ligaments of the ankle are often damaged in ankle inversion injuries. Ankle inversion may also cause injury to other structures located around the ankle or further away, such as the common fibular nerve. Few descriptions exist of common fibular nerve injury associated with ankle sprains and chronic ankle instability. We describe the case of a patient who sustained common fibular nerve injury during each of two ankle sprain recurrences involving the lateral collateral ligaments. Our objectives are to illustrate the links between common fibular nerve and lateral collateral ligament injuries and to emphasize the importance of the neurological evaluation in patients seen for ankle sprains or chronic ankle instability. Copyright © 2010 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

Morphological differences in skeletal muscle atrophy of rats with motor nerve and/or sensory nerve injury★

PubMed Central

Zhao, Lei; Lv, Guangming; Jiang, Shengyang; Yan, Zhiqiang; Sun, Junming; Wang, Ling; Jiang, Donglin

2012-01-01

Skeletal muscle atrophy occurs after denervation. The present study dissected the rat left ventral root and dorsal root at L4-6 or the sciatic nerve to establish a model of simple motor nerve injury, sensory nerve injury or mixed nerve injury. Results showed that with prolonged denervation time, rats with simple motor nerve injury, sensory nerve injury or mixed nerve injury exhibited abnormal behavior, reduced wet weight of the left gastrocnemius muscle, decreased diameter and cross-sectional area and altered ultrastructure of muscle cells, as well as decreased cross-sectional area and increased gray scale of the gastrocnemius muscle motor end plate. Moreover, at the same time point, the pathological changes were most severe in mixed nerve injury, followed by simple motor nerve injury, and the changes in simple sensory nerve injury were the mildest. These findings indicate that normal skeletal muscle morphology is maintained by intact innervation. Motor nerve injury resulted in larger damage to skeletal muscle and more severe atrophy than sensory nerve injury. Thus, reconstruction of motor nerves should be considered first in the clinical treatment of skeletal muscle atrophy caused by denervation. PMID:25337102

Functional and Physical Outcomes following Use of a Flexible CO2 Laser Fiber and Bipolar Electrocautery in Close Proximity to the Rat Sciatic Nerve with Correlation to an In Vitro Thermal Profile Model

PubMed Central

Robinson, A. M.; Fishman, A. J.; Bendok, B. R.; Richter, C.-P.

2015-01-01

This study compared functional and physical collateral damage to a nerve when operating a Codman MALIS Bipolar Electrosurgical System CMC-III or a CO2 laser coupled to a laser, with correlation to an in vitro model of heating profiles created by the devices in thermochromic ink agarose. Functional damage of the rat sciatic nerve after operating the MALIS or CO2 laser at various power settings and proximities to the nerve was measured by electrically evoked nerve action potentials, and histology of the nerve was used to assess physical damage. Thermochromic ink dissolved in agarose was used to model the spatial and temporal profile of the collateral heating zone of the electrosurgical system and the laser ablation cone. We found that this laser can be operated at 2 W directly above the nerve with minimal damage, while power settings of 5 W and 10 W resulted in acute functional and physical nerve damage, correlating with the maximal heating cone in the thermochromic ink model. MALIS settings up to 40 (11 W) did not result in major functional or physical nerve damage until the nerve was between the forceps tips, correlating with the hottest zone, localized discretely between the tips. PMID:25699266

Pathophysiology of blast-induced ocular trauma in rats after repeated exposure to low-level blast overpressure.

PubMed

Choi, Jae Hyek; Greene, Whitney A; Johnson, Anthony J; Chavko, Mikulas; Cleland, Jeffery M; McCarron, Richard M; Wang, Heuy-Ching

2015-04-01

The incidence of blast-induced ocular injury has dramatically increased due to advances in weaponry and military tactics. A single exposure to blast overpressure (BOP) has been shown to cause damage to the eye in animal models; however, on the battlefield, military personnel are exposed to BOP multiple times. The effects of repeated exposures to BOP on ocular tissues have not been investigated. The purpose of this study is to characterize the effects of single or repeated exposure on ocular tissues. A compressed air shock tube was used to deliver 70 ± 7 KPa BOP to rats, once (single blast overpressure [SBOP]) or once daily for 5 days (repeated blast overpressure [RBOP]). Immunohistochemistry was performed to characterize the pathophysiology of ocular injuries induced by SBOP and RBOP. Apoptosis was determined by quantification activated caspase 3. Gliosis was examined by detection of glial fibrillary acidic protein (GFAP). Inflammation was examined by detection of CD68. Activated caspase 3 was detected in ocular tissues from all animals subjected to BOP, while those exposed to RBOP had more activated caspase 3 in the optic nerve than those exposed to SBOP. GFAP was detected in the retinas from all animals subjected to BOP. CD68 was detected in optic nerves from all animals exposed to BOP. SBOP and RBOP induced retinal damage. RBOP caused more apoptosis in the optic nerve than SBOP, suggesting that RBOP causes more severe optic neuropathy than SBOP. SBOP and RBOP caused gliosis in the retina and increased inflammation in the optic nerve. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

Direct Conversion of Human Fibroblasts into Schwann Cells that Facilitate Regeneration of Injured Peripheral Nerve In Vivo.

PubMed

Sowa, Yoshihiro; Kishida, Tsunao; Tomita, Koichi; Yamamoto, Kenta; Numajiri, Toshiaki; Mazda, Osam

2017-04-01

Schwann cells (SCs) play pivotal roles in the maintenance and regeneration of the peripheral nervous system. Although transplantation of SCs enhances repair of experimentally damaged peripheral and central nerve tissues, it is difficult to prepare a sufficient number of functional SCs for transplantation therapy without causing adverse events for the donor. Here, we generated functional SCs by somatic cell reprogramming procedures and demonstrated their capability to promote peripheral nerve regeneration. Normal human fibroblasts were phenotypically converted into SCs by transducing SOX10 and Krox20 genes followed by culturing for 10 days resulting in approximately 43% directly converted Schwann cells (dSCs). The dSCs expressed SC-specific proteins, secreted neurotrophic factors, and induced neuronal cells to extend neurites. The dSCs also displayed myelin-forming capability both in vitro and in vivo. Moreover, transplantation of the dSCs into the transected sciatic nerve in mice resulted in significantly accelerated regeneration of the nerve and in improved motor function at a level comparable to that with transplantation of the SCs obtained from a peripheral nerve. The dSCs induced by our procedure may be applicable for novel regeneration therapy for not only peripheral nerve injury but also for central nerve damage and for neurodegenerative disorders related to SC dysfunction. Stem Cells Translational Medicine 2017;6:1207-1216. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Management of peripheral facial nerve palsy

PubMed Central

2008-01-01

Peripheral facial nerve palsy (FNP) may (secondary FNP) or may not have a detectable cause (Bell’s palsy). Three quarters of peripheral FNP are primary and one quarter secondary. The most prevalent causes of secondary FNP are systemic viral infections, trauma, surgery, diabetes, local infections, tumor, immunological disorders, or drugs. The diagnosis of FNP relies upon the presence of typical symptoms and signs, blood chemical investigations, cerebro-spinal-fluid-investigations, X-ray of the scull and mastoid, cerebral MRI, or nerve conduction studies. Bell’s palsy may be diagnosed after exclusion of all secondary causes, but causes of secondary FNP and Bell’s palsy may coexist. Treatment of secondary FNP is based on the therapy of the underlying disorder. Treatment of Bell’s palsy is controversial due to the lack of large, randomized, controlled, prospective studies. There are indications that steroids or antiviral agents are beneficial but also studies, which show no beneficial effect. Additional measures include eye protection, physiotherapy, acupuncture, botulinum toxin, or possibly surgery. Prognosis of Bell’s palsy is fair with complete recovery in about 80% of the cases, 15% experience some kind of permanent nerve damage and 5% remain with severe sequelae. PMID:18368417

Nerve damage in dentistry.

PubMed

Pogrel, M Anthony

2017-01-01

Many forms of dental treatment have the potential to cause injury to the oral branches of the trigeminal nerve, including local anesthetic injections, root canal therapy, implant insertion, bone grafting, and dentoalveolar surgery. Based on the records of a referral center with more than 30 years' experience in managing 3200 of these injuries, this article reviews etiology and prevention; suggests criteria for referral of patients; and discusses treatment for the various types of injury and the results of such treatment.

Peripheral facial weakness (Bell's palsy).

PubMed

Basić-Kes, Vanja; Dobrota, Vesna Dermanović; Cesarik, Marijan; Matovina, Lucija Zadro; Madzar, Zrinko; Zavoreo, Iris; Demarin, Vida

2013-06-01

Peripheral facial weakness is a facial nerve damage that results in muscle weakness on one side of the face. It may be idiopathic (Bell's palsy) or may have a detectable cause. Almost 80% of peripheral facial weakness cases are primary and the rest of them are secondary. The most frequent causes of secondary peripheral facial weakness are systemic viral infections, trauma, surgery, diabetes, local infections, tumor, immune disorders, drugs, degenerative diseases of the central nervous system, etc. The diagnosis relies upon the presence of typical signs and symptoms, blood chemistry tests, cerebrospinal fluid investigations, nerve conduction studies and neuroimaging methods (cerebral MRI, x-ray of the skull and mastoid). Treatment of secondary peripheral facial weakness is based on therapy for the underlying disorder, unlike the treatment of Bell's palsy that is controversial due to the lack of large, randomized, controlled, prospective studies. There are some indications that steroids or antiviral agents are beneficial but there are also studies that show no beneficial effect. Additional treatments include eye protection, physiotherapy, acupuncture, botulinum toxin, or surgery. Bell's palsy has a benign prognosis with complete recovery in about 80% of patients, 15% experience some mode of permanent nerve damage and severe consequences remain in 5% of patients.

A fully-automatic fast segmentation of the sub-basal layer nerves in corneal images.

PubMed

Guimarães, Pedro; Wigdahl, Jeff; Poletti, Enea; Ruggeri, Alfredo

2014-01-01

Corneal nerves changes have been linked to damage caused by surgical interventions or prolonged contact lens wear. Furthermore nerve tortuosity has been shown to correlate with the severity of diabetic neuropathy. For these reasons there has been an increasing interest on the analysis of these structures. In this work we propose a novel, robust, and fast fully automatic algorithm capable of tracing the sub-basal plexus nerves from human corneal confocal images. We resort to logGabor filters and support vector machines to trace the corneal nerves. The proposed algorithm traced most of the corneal nerves correctly (sensitivity of 0.88 ± 0.06 and false discovery rate of 0.08 ± 0.06). The displayed performance is comparable to a human grader. We believe that the achieved processing time (0.661 ± 0.07 s) and tracing quality are major advantages for the daily clinical practice.

Lingual nerve damage after mandibular third molar surgery: a randomized clinical trial.

PubMed

Gomes, Ana Cláudia Amorim; Vasconcelos, Belmiro Cavalcanti do Egito; de Oliveira e Silva, Emanuel Dias; da Silva, Luiz Carlos Ferreira

2005-10-01

The objective of this study was to clinically evaluate the frequency, type, and risk factors for lingual nerve damage after mandibular third molar surgery with reference to lingual flap retraction. A total of fifty-five patients referred for bilateral mandibular third molar removal were included in this study. Each patient was randomly allotted to have the procedure performed on 1 side (experimental group) with lingual flap retraction. On the opposite side (control group), the same procedure was performed without lingual flap retraction. Lingual nerve damage occurred in 9.1% in the experimental group in which lingual flap retraction was performed. In the control group, damage to the lingual nerve was not observed. The difference was statistically significant (P <.001) as measured by the Cochran test. Lingual nerve retraction represented a risk factor to temporary lingual nerve damage during mandibular third molar surgery.

FREQUENCY OF LINGUAL NERVE INJURY IN MANDIBULAR THIRD MOLAR EXTRACTION: A COMPARISON OF TWO SURGICAL TECHNIQUES.

PubMed

Shad, Samia; Shah, Syed Majid Hussain; Alamgir; Abbasi, Masroor Manshad

2015-01-01

Surgical removal of impacted mandibular third molar is associated with a number of complications including postoperative bleeding, dry socket, postoperative infection, and injury to regional nerves. Lingual nerve damage is one of the main complications. To prevent this complication different techniques had been used. Lingual flap reflection is one of these procedures in which lingual soft tissue is reflected and retracted deliberately, the nerve is identified and is kept out of the surgical field. The objective of this study was to evaluate a surgical technique for third molar removal which is associated with minimum frequency of lingual nerve damage. A randomized controlled trial was performed. A total of 380 patients with impacted mandibular third molars were included in this study. Each patient was allotted randomly by blocked randomization to group A where procedure was performed by reflection and retraction of lingual flap in addition to buccal flap and group B where procedure was performed by retraction of buccal flap only. Lingual nerve damage occurred in 8.94% in Group A in which lingual flap retraction was performed but damage was reversible. In group B, 2.63% lingual nerve damage was observed and nature of damage was permanent. The difference was statistically significant (p=0.008). Lingual flap retraction poses 3.4 times increased risk of lingual nerve damage during extraction of mandibular third molar when lingual flap is retracted but the nature of damage is reversible.

Acupuncture therapy to the head and face to treat post-trauma paralysis of peripheral fascial nerve dextra

NASA Astrophysics Data System (ADS)

Mihardja, H.; Meuratana, PA; Ibrahim, A.

2017-08-01

Damage to the facial nerve due to trauma from traffic accidents is the second most common cause of paralysis of the facial nerve. The treatments include both pharmacological and non-pharmacological therapy. Acupuncture is a method of treatment that applies evidence-based medical principles and uses anatomy, physiology, and pathology to place needles atcertain acupuncture points. This paper describes a 26-year-old female patient with right-side facial palsy following a traffic accident who had animproved Brackmann’s score after 12 sessions of acupuncture treatment. The acupuncture points were chosen based on Liu Yan’sbrain-clearing needling technique. Acupuncture can shorten healing time and improve the effect of treatment for facial-nerve paralysis.

Structural evidence that botulinum toxin blocks neuromuscular transmission by impairing the calcium influx that normally accompanies nerve depolarization

PubMed Central

1981-01-01

Taking advantage of the fact that nerve terminal mitochondria swell and sequester calcium during repetitive nerve stimulation, we here confirm that this change is caused by calcium influx into the nerve and use this fact to show that botulinum toxin abolishes such calcium influx. The optimal paradigm for producing the mitochondrial changes in normal nerves worked out to be 5 min of stimulation at 25 Hz in frog Ringer's solution containing five time more calcium than normal. Applying this same stimulation paradigm to botulinum-intoxicated nerves produced no mitochondrial changes at all. Only when intoxicated nerves were stimulated in 4-aminopyridine (which grossly exaggerates calcium currents in normal nerves) or when they were soaked in black widow spider venom (which is a nerve-specific calcium ionophore) could nerve mitochondria be induced to swell and accumulate calcium. These results indicate that nerve mitochondria are not damaged directly by the toxin and point instead to a primary inhibition of the normal depolarization- evoked calcium currents that accompany nerve activity. Because these currents normally provide the calcium that triggers transmitter secretion from the nerve, this demonstration of their inhibition helps to explain how botulinum toxin paralyzes. PMID:6259176

Glaucoma and its association with obstructive sleep apnea: A narrative review

PubMed Central

Chaitanya, Aditya; Pai, Vijaya H.; Mohapatra, Aswini Kumar; Ve, Ramesh S.

2016-01-01

Obstructive sleep apnea (OSA) is one of the systemic risk factors for glaucoma which causes irreversible visual field (VF) damage. We reviewed the published data of all types of studies on the association between these two conditions and papers regarding functional and structural changes related to glaucomatous damage using Scopus, web of science, and PubMed databases. There is evidence that the prevalence of glaucoma is higher in OSA patients, which independent of intraocular pressure (IOP). Studies have reported thinning of retinal nerve fiber layer (RNFL), alteration of optic nerve head, choroidal and macular thickness, and reduced VF sensitivity in patients of OSA with no history glaucoma. A negative correlation of apnea-hypopnea index with RNFL and VF indices has been described in some studies. Raised IOP was noted which is possibly related to obesity, supine position during sleep, and raised intracranial pressure. Diurnal fluctuations of IOP show more variations in OSA patients before and after continuous positive airway pressure (CPAP) therapy when compared with the normal cases. The vascular factors behind the pathogenesis include recurrent hypoxia with increased vascular resistance, oxidative stress damage to the optic nerve. In conclusion, comprehensive glaucoma evaluation should be recommended in patients with OSA and should also periodically monitor IOP during CPAP treatment which may trigger the progression of glaucomatous damage. PMID:27843225

Glaucoma

MedlinePlus

... damage in animal models of elevated IOP. Nerve cell regeneration is another approach to repairing neuronal tissue damaged ... or injury. NIH-supported researchers recently provoked nerve cell regeneration in rodents by activating a nerve cell’s natural ...

Analysis and evaluation of relative positions of mandibular third molar and mandibular canal impacts

PubMed Central

Kim, Hang-Gul

2014-01-01

Objectives This study used cone-beam computed tomography (CBCT) images to categorize the relationships between the mandibular canal and the roots and investigated the prevalence of nerve damage. Materials and Methods Through CBCT images, contact and three-dimensional positional relationships between the roots of the mandibular third molar and the mandibular canal were investigated. With this data, prevalence of nerve damage according to the presence of contact and three-dimensional positional relationships was studied. Other factors that affected the prevalence of nerve damage were also investigated. Results When the mandibular third molar and the mandibular canal were shown to have direct contact in CBCT images, the prevalence of nerve damage was higher than in other cases. Also, in cases where the mandibular canal was horizontally lingual to the mandibular third molar and the mandibular canal was vertically at the cervical level of the mandibular third molar, the prevalence of nerve damage was higher than in opposite cases. The percentage of mandibular canal contact with the roots of the mandibular third molar was higher when the mandibular canal was horizontally lingual to the mandibular third molar. Finally, the prevalence of nerve damage was higher when the diameter of the mandibular canal lumen suddenly decreased at the contact area between the mandibular canal and the roots, as shown in CBCT images. Conclusion The three-dimensional relationship of the mandibular third molar and the mandibular canal can help predict nerve damage and can guide patient expectations of the possibility and extent of nerve damage. PMID:25551092

Ultrastructural aspects of mouse nerve-muscle preparation exposed to Bothrops jararacussu and Bothrops bilineatus venoms and their toxins BthTX-I and Bbil-TX: Unknown myotoxic effects.

PubMed

Melaré, Rodolfo; Floriano, Rafael Stuani; Gracia, Marta; Rodrigues-Simioni, Léa; Cruz-Höfling, Maria Alice da; Rocha, Thalita

2016-11-01

Bites by Bothrops snakes normally induce local pain, haemorrhage, oedema and myonecrosis. Mammalian isolated nerve-muscle preparations exposed to Bothrops venoms and their phospholipase A 2 toxins (PLA 2 ) can exhibit a neurotoxic pattern as increase in frequency of miniature end-plate potentials (MEPPs) as well as in amplitude of end-plate potentials (EPPs); neuromuscular facilitation followed by complete and irreversible blockade without morphological evidence for muscle damage. In this work, we analysed the ultrastructural damage induced by Bothrops jararacussu and Bothrops bilineatus venoms and their PLA 2 toxins (BthTX-I and Bbil-TX) in mouse isolated nerve-phrenic diaphragm preparations (PND). Under transmission electron microscopy (TEM), PND preparations previously exposed to B. jararacussu and B. bilineatus venoms and BthTX-I and Bbil-TX toxins showed hypercontracted and loosed myofilaments; unorganized sarcomeres; clusters of edematous sarcoplasmic reticulum and mitochondria; abnormal chromatin distribution or apoptotic-like nuclei. The principal affected organelles, mitochondria and sarcoplasmic reticulum, were those related to calcium buffering and, resulting in sarcomeres and myofilaments hypercontraction. Schwann cells were also damaged showing edematous axons and mitochondria as well as myelin sheath alteration. These ultrastructural changes caused by both of Bothrops venoms and toxins indicate that the neuromuscular blockade induced by them in vitro can also be associated with nerve and muscle degeneration. © 2016 Wiley Periodicals, Inc.

Retrospective review of thoracic neural damage during lung ablation - what the interventional radiologist needs to know about neural thoracic anatomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palussiere, Jean, E-mail: j.palussiere@bordeaux.unicancer.fr; Canella, Mathieu; Cornelis, Francois

Background and Purpose: Radiofrequency ablation (RFA) is associated with low neural morbidity compared with surgery, which commonly causes debilitating long-term pain. The purpose was to review the thoracic neural anatomy relevant to percutaneous RFA and to retrospectively review symptomatic nerve injury after lung RFA at our institution. Materials and Methods: We retrospectively examined all symptomatic nerve injuries occurring after computed tomography (CT)-guided RFA treatment of lung tumors for 462 patients/509 procedures/708 lesions treated at our large tertiary referral centre during 10 years. Results: Eight patients experienced neurological complications after heating during the RFA procedure. These complications occurred in the phrenicmore » (n = 1), brachial (n = 3), left recurrent (n = 1), and intercostal nerves (n = 2) and the stellate ganglion (n = 1). Three were grade 2, four grade 3 and one grade 4 injuries (CTCAE v3). Conclusion: Although rare, neurological complications can occur after RFA, and they can occasionally be severe. To prevent these complications, it is important for the interventional radiologist to be aware of the anatomy of nervous structures and to attempt to identify nerves on CT scans during the RFA procedure. Creating a pneumothorax can be useful to avoid nerve damage and related clinical complications.« less

Increased expression of CaV3.2 T-type calcium channels in damaged DRG neurons contributes to neuropathic pain in rats with spared nerve injury.

PubMed

Kang, Xue-Jing; Chi, Ye-Nan; Chen, Wen; Liu, Feng-Yu; Cui, Shuang; Liao, Fei-Fei; Cai, Jie; Wan, You

2018-01-01

Ion channels are very important in the peripheral sensitization in neuropathic pain. Our present study aims to investigate the possible contribution of Ca V 3.2 T-type calcium channels in damaged dorsal root ganglion neurons in neuropathic pain. We established a neuropathic pain model of rats with spared nerve injury. In these model rats, it was easy to distinguish damaged dorsal root ganglion neurons (of tibial nerve and common peroneal nerve) from intact dorsal root ganglion neurons (of sural nerves). Our results showed that Ca V 3.2 protein expression increased in medium-sized neurons from the damaged dorsal root ganglions but not in the intact ones. With whole cell patch clamp recording technique, it was found that after-depolarizing amplitudes of the damaged medium-sized dorsal root ganglion neurons increased significantly at membrane potentials of -85 mV and -95 mV. These results indicate a functional up-regulation of Ca V 3.2 T-type calcium channels in the damaged medium-sized neurons after spared nerve injury. Behaviorally, blockade of Ca V 3.2 with antisense oligodeoxynucleotides could significantly reverse mechanical allodynia. These results suggest that Ca V 3.2 T-type calcium channels in damaged medium-sized dorsal root ganglion neurons might contribute to neuropathic pain after peripheral nerve injury.

3D papillary image capturing by the stereo fundus camera system for clinical diagnosis on retina and optic nerve

NASA Astrophysics Data System (ADS)

Motta, Danilo A.; Serillo, André; de Matos, Luciana; Yasuoka, Fatima M. M.; Bagnato, Vanderlei S.; Carvalho, Luis A. V.

2014-03-01

Glaucoma is the second main cause of the blindness in the world and there is a tendency to increase this number due to the lifetime expectation raise of the population. Glaucoma is related to the eye conditions, which leads the damage to the optic nerve. This nerve carries visual information from eye to brain, then, if it has damage, it compromises the visual quality of the patient. In the majority cases the damage of the optic nerve is irreversible and it happens due to increase of intraocular pressure. One of main challenge for the diagnosis is to find out this disease, because any symptoms are not present in the initial stage. When is detected, it is already in the advanced stage. Currently the evaluation of the optic disc is made by sophisticated fundus camera, which is inaccessible for the majority of Brazilian population. The purpose of this project is to develop a specific fundus camera without fluorescein angiography and red-free system to accomplish 3D image of optic disc region. The innovation is the new simplified design of a stereo-optical system, in order to make capable the 3D image capture and in the same time quantitative measurements of excavation and topography of optic nerve; something the traditional fundus cameras do not do. The dedicated hardware and software is developed for this ophthalmic instrument, in order to permit quick capture and print of high resolution 3D image and videos of optic disc region (20° field-of-view) in the mydriatic and nonmydriatic mode.

The surgical anatomy of the infrapatellar branch of the saphenous nerve in relation to incisions for anteromedial knee surgery.

PubMed

Kerver, A L A; Leliveld, M S; den Hartog, D; Verhofstad, M H J; Kleinrensink, G J

2013-12-04

Iatrogenic injury to the infrapatellar branch of the saphenous nerve is a common complication of surgical approaches to the anteromedial side of the knee. A detailed description of the relative anatomic course of the nerve is important to define clinical guidelines and minimize iatrogenic damage during anterior knee surgery. In twenty embalmed knees, the infrapatellar branch of the saphenous nerve was dissected. With use of a computer-assisted surgical anatomy mapping tool, safe and risk zones, as well as the location-dependent direction of the nerve, were calculated. The location of the infrapatellar branch of the saphenous nerve is highly variable, and no definite safe zone could be identified. The infrapatellar branch runs in neither a purely horizontal nor a vertical course. The course of the branch is location-dependent. Medially, it runs a nearly vertical course; medial to the patellar tendon, it has a -45° distal-lateral course; and on the patella and patellar tendon, it runs a close to horizontal-lateral course. Three low risk zones for iatrogenic nerve injury were identified: one is on the medial side of the knee, at the level of the tibial tuberosity, where a -45° oblique incision is least prone to damage the nerves, and two zones are located medial to the patellar apex (cranial and caudal), where close to horizontal incisions are least prone to damage the nerves. The infrapatellar branch of the saphenous nerve is at risk for iatrogenic damage in anteromedial knee surgery, especially when longitudinal incisions are made. There are three low risk zones for a safer anterior approach to the knee. The direction of the infrapatellar branch of the saphenous nerve is location-dependent. To minimize iatrogenic damage to the nerve, the direction of incisions should be parallel to the direction of the nerve when technically possible. These findings suggest that iatrogenic damage of the infrapatellar branch of the saphenous nerve can be minimized in anteromedial knee surgery when both the location and the location-dependent direction of the nerve are considered when making the skin incision.

Functional regeneration of recurrent laryngeal nerve injury during thyroid surgery using an asymmetrically porous nerve guide conduit in an animal model.

PubMed

Choi, Jeong-Seok; Oh, Se Heang; An, Hye-Young; Kim, Young-Mo; Lee, Jin Ho; Lim, Jae-Yol

2014-01-01

Vocal cord paralysis (VCP) caused by recurrent laryngeal nerve (RLN) damage during thyroidectomy commonly results in serious medico-legal problems. The purpose of this study was to evaluate the usefulness of an asymmetrically porous polycaprolactone (PCL)/Pluronic F127 nerve guide conduit (NGC) for functional regeneration in a RLN injury animal model. A biodegradable, asymmetrically porous PCL/F127 NGC with selective permeability was fabricated for use in this study. A 10-mm segment of left RLN was resected in 28 New Zealand white rabbits, and then an asymmetrically porous NGC or a nonporous silicone tube was interposed between both stumps and securely fixed. Vocal cord mobility was endoscopically evaluated at one, four, and eight weeks postoperatively. Nerve growth through NGCs was assessed by toluidine blue staining, and thyroarytenoid (TA) muscle atrophy was evaluated by hematoxylin and eosin staining. Immunohistochemical stainings for acetylcholinesterase (AchE), anti-neurofilament (NF), and anti-S100 protein were also conducted, and transmission electron microscopy (TEM) was used to evaluate functional nerve regeneration. At eight weeks postoperatively, endoscopic evaluations showed significantly better recovery from VCP in the asymmetrically porous PCL/F127 NGC group (6 of 10 rabbits) than in the silicone tube group (1 of 10 rabbits). Continued nerve growth on the damaged nerve endings was observed with time in the asymmetrically porous PCL/F127 NGC-interposed RLNs. TA muscle dimensions and AchE expressions in TA muscle were significantly greater in the asymmetrically porous PCL/F127 NGC group than in the silicone tube group. Furthermore, immunohistochemical staining revealed the expression of NF and S100 protein in the regenerated nerves in the asymmetrically porous PCL/F127 NGC group at eight weeks postoperatively, and at this time, TEM imaging showed myelinated axons in the regenerated RLNs. The study shows that asymmetrically porous PCL/F127 NGC provides a favorable environment for RLN regeneration and that it has therapeutic potential for the regeneration of RLN damage.

Functional Regeneration of Recurrent Laryngeal Nerve Injury During Thyroid Surgery Using an Asymmetrically Porous Nerve Guide Conduit in an Animal Model

PubMed Central

Choi, Jeong-Seok; Oh, Se Heang; An, Hye-Young; Kim, Young-Mo; Lee, Jin Ho

2014-01-01

Background: Vocal cord paralysis (VCP) caused by recurrent laryngeal nerve (RLN) damage during thyroidectomy commonly results in serious medico-legal problems. The purpose of this study was to evaluate the usefulness of an asymmetrically porous polycaprolactone (PCL)/Pluronic F127 nerve guide conduit (NGC) for functional regeneration in a RLN injury animal model. Methods: A biodegradable, asymmetrically porous PCL/F127 NGC with selective permeability was fabricated for use in this study. A 10-mm segment of left RLN was resected in 28 New Zealand white rabbits, and then an asymmetrically porous NGC or a nonporous silicone tube was interposed between both stumps and securely fixed. Vocal cord mobility was endoscopically evaluated at one, four, and eight weeks postoperatively. Nerve growth through NGCs was assessed by toluidine blue staining, and thyroarytenoid (TA) muscle atrophy was evaluated by hematoxylin and eosin staining. Immunohistochemical stainings for acetylcholinesterase (AchE), anti-neurofilament (NF), and anti-S100 protein were also conducted, and transmission electron microscopy (TEM) was used to evaluate functional nerve regeneration. Results: At eight weeks postoperatively, endoscopic evaluations showed significantly better recovery from VCP in the asymmetrically porous PCL/F127 NGC group (6 of 10 rabbits) than in the silicone tube group (1 of 10 rabbits). Continued nerve growth on the damaged nerve endings was observed with time in the asymmetrically porous PCL/F127 NGC-interposed RLNs. TA muscle dimensions and AchE expressions in TA muscle were significantly greater in the asymmetrically porous PCL/F127 NGC group than in the silicone tube group. Furthermore, immunohistochemical staining revealed the expression of NF and S100 protein in the regenerated nerves in the asymmetrically porous PCL/F127 NGC group at eight weeks postoperatively, and at this time, TEM imaging showed myelinated axons in the regenerated RLNs. Conclusion: The study shows that asymmetrically porous PCL/F127 NGC provides a favorable environment for RLN regeneration and that it has therapeutic potential for the regeneration of RLN damage. PMID:24015805

Unpredictable interference of new transcranial motor-evoked potential monitor against the implanted pacemaker.

PubMed

Hayashi, Kazuko

2016-12-01

Recently, NuVasive NV-M5 nerve monitoring system, a new transcranial motor-evoked potential (TcMEP) monitor, has been introduced with the spread of flank-approach spinal operations such as extreme lateral interbody fusion, to prevent nerve damage. Conventional TcMEP monitors use changes in MEP wave patterns, such as amplitude and/or latency, whereas the NV-M5 nerve monitor system first measures the MEP baseline waveform from the transcranial-evoked potential then measures the electric current necessary to obtain the standard of the previous baseline wave pattern at subsequent monitoring times. The NV-M5 monitor determines nerve damage according to the increase in necessary electric current threshold. The NV-M5 monitor also uses a local electrical stimulation mode to monitor the safety of setting screws into the lumbar vertebrae. In this way, various electrical stimulations with various durations and frequencies are used, and electrical noise may result in unpredictable interference with cardiac pacemakers. We performed anesthetic management of extreme lateral interbody fusion surgery using the NV-M5 in a patient with an implanted pacemaker, during which TcMEP stimulation caused interference with the implanted pacemaker. Copyright © 2016 Elsevier Inc. All rights reserved.

De Novo Intraneural Arachnoid Cyst Presenting with Complete Third Nerve Palsy: Case Report and Literature Review.

PubMed

Brewington, Danielle; Petrov, Dmitriy; Whitmore, Robert; Liu, Grant; Wolf, Ronald; Zager, Eric L

2017-02-01

Intraneural arachnoid cyst is an extremely rare etiology of isolated cranial nerve palsy. Although seldom encountered in clinical practice, this pathology is amenable to surgical intervention. Correct identification and treatment of the cyst are required to prevent permanent nerve damage and potentially reverse the deficits. We describe a rare case of isolated third nerve palsy caused by an intraneural arachnoid cyst. A 49-year-old woman with a recent history of headaches experienced acute onset of painless left-sided third nerve palsy. According to hospital records ptosis, mydriasis, absence of adduction, elevation, and intorsion were noted in the left eye. Computed tomography and magnetic resonance imaging studies showed an extra-axial, 1-cm lesion along the left paraclinoid region, causing mild indentation on the uncus. There was dense fluid layering dependently concerning for hemorrhage, but no evidence of aneurysms. A pterional craniotomy was performed, revealing a completely intraneural arachnoid cyst in the third nerve. The cyst was successfully fenestrated. At 7-month follow-up, the left eye had recovered intact intorsion and some adduction, but the left pupil remained dilated and nonreactive. There was still no elevation and no afferent pupillary defect. Double vision persisted with partial improvement in the ptosis, opening up to more than 75% early in the day. To our knowledge, this is the first report of an intraneural arachnoid cyst causing isolated third nerve palsy. This rare pathology proves to be both a diagnostic and therapeutic challenge. Copyright © 2016 Elsevier Inc. All rights reserved.

RGC Neuroprotection Following Optic Nerve Trauma Mediated By Intranasal Delivery of Amnion Cell Secretome

PubMed Central

Grinblat, Gabriela A.; Khan, Reas S.; Dine, Kimberly; Wessel, Howard; Brown, Larry; Shindler, Kenneth S.

2018-01-01

Purpose Intranasally delivered ST266, the biological, proteinaceous secretome of amnion-derived multipotent progenitor cells, reduces retinal ganglion cell (RGC) loss, optic nerve inflammation, and demyelination in experimental optic neuritis. This unique therapy and novel administration route delivers numerous cytokines and growth factors to the eye and optic nerve, suggesting a potential to also treat other optic neuropathies. Thus, ST266-mediated neuroprotection was examined following traumatic optic nerve injury. Methods Optic nerve crush injury was surgically induced in C57BL/6J mice. Mice were treated daily with intranasal PBS or ST266. RGC function was assessed by optokinetic responses (OKRs), RGCs were counted, and optic nerve sections were stained with luxol fast blue and anti-neurofilament antibodies to assess myelin and RGC axon damage. Results Intranasal ST266 administered daily for 5 days, beginning at the time that a 1-second optic nerve crush was performed, significantly attenuated OKR decreases. Furthermore, ST266 treatment reduced damage to RGC axons and myelin within optic nerves, and blocked RGC loss. Following a 4-second optic nerve crush, intranasal ST266 increased RGC survival and showed a trend toward reduced RGC axon and myelin damage. Ten days following optic nerve crush, ST266 prevented myelin damage, while also inducing a trend toward increased RGC survival and visual function. Conclusions ST266 significantly attenuates traumatic optic neuropathy. Neuroprotective effects of this unique combination of biologic molecules observed here and previously in optic neuritis suggest potential broad application for preventing neuronal damage in multiple optic nerve disorders. Furthermore, results support intranasal delivery as a novel, noninvasive therapeutic modality for eyes and optic nerves. PMID:29847652

[Prevention of laryngeal nerve lesions in thyroid surgery].

PubMed

Balanzoni, S; Altini, R; Pasi, L; Fussi, F

1994-04-01

The authors analyse problems related to laryngeal nerves in matters of thyroid surgery. As a matter of fact laryngeal nerve injury is still one of the most common complications for patients undergoing thyroid surgery. Although the sharp reduction in this drawback, due to a better anesthesiological technique and a wider surgical experience, the most representative case report show an incidence ranging from 3% to 5%. After a short introduction on surgical anatomy, attention is drawn to the "recurrent nerve risk" but also the superior laryngeal nerve too, often injured with modifications of the vocal tone and serious consequences for particular professional groups. There fore it is of basic importance, for surgeons performing thyroid surgery, to dissect the recurrent nerve for all its length, that is from the crossing with the inferior thyroid artery to the point where it enters the cricothyroid cartilage; in order not to damage the thin nervous branches and eventually anatomic variations that, when looked for, are cause of mistakes even for the most experienced surgeons.

Electromechanical Nerve Stimulator

NASA Technical Reports Server (NTRS)

Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

1993-01-01

Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

Spectral-Domain Optical Coherence Tomography for Glaucoma Diagnosis

PubMed Central

Gracitelli, Carolina P.B; Abe, Ricardo Y; Medeiros, Felipe A

2015-01-01

Identification of structural damage to the optic nerve and retinal nerve fiber layer (RNFL) is an essential component of diagnosis and management of glaucoma. The introduction of spectral-domain OCT (SD-OCT) has allowed objective quantification of damage to these structures with unprecedented resolution. In addition, recent attention has been directed towards imaging the macular area for quantifying loss of neural tissue caused by the disease. Many studies have evaluated and compared the diagnostic accuracies of a variety of parameters that can be obtained from imaging these areas of the ocular fundus. In this article, we critically review the existing literature evaluating the diagnostic accuracy of SD-OCT in glaucoma and we discuss issues related to how SD-OCT results should be incorporated into clinical practice. PMID:26069519

Tactile stimulation partially prevents neurodevelopmental changes in visual tract caused by early iron deficiency.

PubMed

Horiquini-Barbosa, Everton; Gibb, Robbin; Kolb, Bryan; Bray, Douglas; Lachat, Joao-Jose

2017-02-15

Iron deficiency has a critical impact on maturational mechanisms of the brain and the damage related to neuroanatomical parameters is not satisfactorily reversed after iron replacement. However, emerging evidence suggest that enriched early experience may offer great therapeutic efficacy in cases of nutritional disorders postnatally, since the brain is remarkably responsive to its interaction with the environment. Given the fact that tactile stimulation (TS) treatment has been previously shown to be an effective therapeutic approach and with potential application to humans, here we ask whether exposure to TS treatment, from postnatal day (P) 1 to P32 for 3min/day, could also be employed to prevent neuroanatomical changes in the optic nerve of rats maintained on an iron-deficient diet during brain development. We found that iron deficiency changed astrocyte, oligodendrocyte, damaged fiber, and myelinated fiber density, however, TS reversed the iron-deficiency-induced alteration in oligodendrocyte, damaged fiber and myelinated fiber density, but failed to reverse astrocyte density. Our results suggest that early iron deficiency may act by disrupting the timing of key steps in visual system development thereby modifying the normal progression of optic nerve maturation. However, optic nerve development is sensitive to enriching experiences, and in the current study we show that this sensitivity can be used to prevent damage from postnatal iron deficiency during the critical period. Copyright © 2016 Elsevier B.V. All rights reserved.

New Method of Injured Nerve Repair.

PubMed

Korsak, Alina; Likhodiievskyi, Volodymyr; Sokurenko, Liudmyla; Chaikovsky, Yuri

2018-07-01

 Innovative surgical techniques form the basis of therapeutic approaches to address the negative consequences of nerve damage. This study evaluated the effectiveness of nerve trunk regeneration after the use of an electrosurgical instrument by looking at the patterns of morphological changes in the injured nerve and the structural elements of the segment motor center.  The study was performed on male Wistar rats divided into four groups: group 1, control; group 2, rats with simulated sciatic nerve injury with epineural sutures; 3, rats subjected to an experimental surgical procedure using high-frequency electric welding technology; and 4, rats with simulated sciatic nerve injury without posttransection repair. To study changes in the peripheral stump of the transected nerves and L5 segments of the spinal cord, we used histologic, immunohistochemical, and morphometric methods.  At week 12 after the surgery, there were more S-100+ Schwann cells, increased expression of neurofilaments (NFs), and glial fibrillary acidic protein in the peripheral stump in group 3 than in groups 2 and 4, which indicates enhanced neurotization and myelination. Group 3 animals demonstrated reduced expression of S-100 and NFs in the motor center of the spinal cord compared with group 2 that suggests less pronounced reactive changes caused by electric welding technology.  The study showed a novel surgical method using an electrosurgical instrument in a welding mode to stimulate regeneration of the injured nerve and to cause less prominent reactive changes in its segment motor center. Georg Thieme Verlag KG Stuttgart · New York.

[Diagnosis and treatment of peripheral neuropathy induced by ANCA-associated vasculitis].

PubMed

Hattori, Naoki

2014-07-01

ANCA-associated vasculitis is induced by necrotizing angiitis of small vessels supplying the peripheral nervous system. Ischemic processes induce neuronal damage and axonal degeneration in the peripheral nerve. Motor dysfunction as well as sensory disturbance and allodynia caused by neuropathic symptoms may influence an individual's activities of daily living and quality of life. Notably, the peripheral nerve is predominantly affected in ANCA-associated vasculitis. We suggest that early diagnosis and appropriate treatment are important to improve survival in and functional prognosis of ANCA-associated vasculitis.

Regional Retinal Ganglion Cell Axon Loss in a Murine Glaucoma Model

PubMed Central

Schaub, Julie A.; Kimball, Elizabeth C.; Steinhart, Matthew R.; Nguyen, Cathy; Pease, Mary E.; Oglesby, Ericka N.; Jefferys, Joan L.; Quigley, Harry A.

2017-01-01

Purpose To determine if retinal ganglion cell (RGC) axon loss in experimental mouse glaucoma is uniform in the optic nerve. Methods Experimental glaucoma was induced for 6 weeks with a microbead injection model in CD1 (n = 78) and C57BL/6 (B6, n = 68) mice. From epoxy-embedded sections of optic nerve 1 to 2 mm posterior to the globe, total nerve area and regional axon density (axons/1600 μm2) were measured in superior, inferior, nasal, and temporal zones. Results Control eyes of CD1 mice have higher axon density and more total RGCs than control B6 mice eyes. There were no significant differences in control regional axon density in all mice or by strain (all P > 0.2, mixed model). Exposure to elevated IOP caused loss of RGC in both strains. In CD1 mice, axon density declined without significant loss of nerve area, while B6 mice had less density loss, but greater decrease in nerve area. Axon density loss in glaucoma eyes was not significantly greater in any region in either mouse strain (both P > 0.2, mixed model). In moderately damaged CD1 glaucoma eyes, and CD1 eyes with the greatest IOP elevation exposure, density loss differed by region (P = 0.05, P = 0.03, mixed model) with the greatest loss in the temporal and superior regions, while in severely injured B6 nerves superior loss was greater than inferior loss (P = 0.01, mixed model, Bonferroni corrected). Conclusions There was selectively greater loss of superior and temporal optic nerve axons of RGCs in mouse glaucoma at certain stages of damage. Differences in nerve area change suggest non-RGC responses differ between mouse strains. PMID:28549091

Compact fluorescence and white-light imaging system for intraoperative visualization of nerves

NASA Astrophysics Data System (ADS)

Gray, Dan; Kim, Evgenia; Cotero, Victoria; Staudinger, Paul; Yazdanfar, Siavash; tan Hehir, Cristina

2012-02-01

Fluorescence image guided surgery (FIGS) allows intraoperative visualization of critical structures, with applications spanning neurology, cardiology and oncology. An unmet clinical need is prevention of iatrogenic nerve damage, a major cause of post-surgical morbidity. Here we describe the advancement of FIGS imaging hardware, coupled with a custom nerve-labeling fluorophore (GE3082), to bring FIGS nerve imaging closer to clinical translation. The instrument is comprised of a 405nm laser and a white light LED source for excitation and illumination. A single 90 gram color CCD camera is coupled to a 10mm surgical laparoscope for image acquisition. Synchronization of the light source and camera allows for simultaneous visualization of reflected white light and fluorescence using only a single camera. The imaging hardware and contrast agent were evaluated in rats during in situ surgical procedures.

A compact fluorescence and white light imaging system for intraoperative visualization of nerves

NASA Astrophysics Data System (ADS)

Gray, Dan; Kim, Evgenia; Cotero, Victoria; Staudinger, Paul; Yazdanfar, Siavash; Tan Hehir, Cristina

2012-03-01

Fluorescence image guided surgery (FIGS) allows intraoperative visualization of critical structures, with applications spanning neurology, cardiology and oncology. An unmet clinical need is prevention of iatrogenic nerve damage, a major cause of post-surgical morbidity. Here we describe the advancement of FIGS imaging hardware, coupled with a custom nerve-labeling fluorophore (GE3082), to bring FIGS nerve imaging closer to clinical translation. The instrument is comprised of a 405nm laser and a white light LED source for excitation and illumination. A single 90 gram color CCD camera is coupled to a 10mm surgical laparoscope for image acquisition. Synchronization of the light source and camera allows for simultaneous visualization of reflected white light and fluorescence using only a single camera. The imaging hardware and contrast agent were evaluated in rats during in situ surgical procedures.

Pain in Chickens and Effects of Beak Trimming

USDA-ARS?s Scientific Manuscript database

Beak trimming may cause pain (acute, chronic or both) in trimmed chickens due to tissue damage and nerve injury. The complexity and plasticity of the nervous system and the animal’s inability to communicate verbally make pain difficult to measure directly. However, pain in animals can be recognized...

Engineering Bi-Layer Nanofibrous Conduits for Peripheral Nerve Regeneration

PubMed Central

Zhu, Yiqian; Wang, Aijun; Patel, Shyam; Kurpinski, Kyle; Diao, Edward; Bao, Xuan; Kwong, George; Young, William L.

2011-01-01

Trauma injuries often cause peripheral nerve damage and disability. A goal in neural tissue engineering is to develop synthetic nerve conduits for peripheral nerve regeneration having therapeutic efficacy comparable to that of autografts. Nanofibrous conduits with aligned nanofibers have been shown to promote nerve regeneration, but current fabrication methods rely on rolling a fibrous sheet into the shape of a conduit, which results in a graft with inconsistent size and a discontinuous joint or seam. In addition, the long-term effects of nanofibrous nerve conduits, in comparison with autografts, are still unknown. Here we developed a novel one-step electrospinning process and, for the first time, fabricated a seamless bi-layer nanofibrous nerve conduit: the luminal layer having longitudinally aligned nanofibers to promote nerve regeneration, and the outer layer having randomly organized nanofibers for mechanical support. Long-term in vivo studies demonstrated that bi-layer aligned nanofibrous nerve conduits were superior to random nanofibrous conduits and had comparable therapeutic effects to autografts for nerve regeneration. In summary, we showed that the engineered nanostructure had a significant impact on neural tissue regeneration in situ. The results from this study will also lead to the scalable fabrication of engineered nanofibrous nerve conduits with designed nanostructure. This technology platform can be combined with drug delivery and cell therapies for tissue engineering. PMID:21501089

Methylmercury causes neuronal cell death through the suppression of the TrkA pathway: In vitro and in vivo effects of TrkA pathway activators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujimura, Masatake, E-mail: fujimura@nimd.go.jp; Usuki, Fusako

Methylmercury (MeHg) is an environmental toxin which induces cell death specific for the nervous systems. Here we show that MeHg causes neuronal cell death through the suppression of the tropomyosin receptor kinase A (TrkA) pathway, and that compounds activating the TrkA pathway prevent MeHg-induced nerve damage in vitro and in vivo. We first investigated the mechanism of MeHg-induced neurotoxicity in differentiating neurons using PC12 cells. Exposure to 100 nM MeHg for 1 day induced apoptosis in differentiating PC12 cells. Further, MeHg-induced apoptosis was preceded by inhibition of neurite extension, as determined by ELISA analyses of the neurite-specific protein neurofilament tripletmore » H protein (NF-H). To determine the mechanism of MeHg-induced apoptosis, we evaluated the effects of MeHg on the TrkA pathway, which is known to regulate neuronal differentiation and viability. Western blot analysis demonstrated that, like the TrkA phosphorylation inhibitor K252a, MeHg inhibited phosphorylation of TrkA and its downstream effectors. Furthermore, GM1 ganglioside and its analog MCC-257, which enhance TrkA phosphorylation, overcame the effect of MeHg in neurons, supporting the involvement of the TrkA pathway in MeHg-induced nerve damage. Finally, we demonstrated that MCC-257 rescued the clinical sign and pathological changes in MeHg-exposed rats. These findings indicate that MeHg-induced apoptosis in neuron is triggered by inhibition of the TrkA pathway, and that GM1 ganglioside and MCC-257 effectively prevent MeHg-induced nerve damage. - Highlights: • Exposure to 100 nM MeHg for 1 day induced apoptosis in differentiating PC12 cells. • Inhibition of neurite extension was involved in MeHg-induced apoptosis. • Like the TrkA phosphorylation inhibitor, MeHg inhibited phosphorylation of TrkA. • GM1 ganglioside and its analog effectively prevented MeHg-induced nerve damage.« less

Acute Compartment Syndrome Which Causes Rhabdomyolysis by Carbon Monoxide Poisoning and Sciatic Nerve Injury Associated with It: A Case Report.

PubMed

Ji, Jung-Woo

2017-09-01

Rhabdomyolysis is most frequently caused by soft tissue injury with trauma to the extremities. Non-traumatic rhabdomyolysis may be caused by alcohol or drug abuse, infection, collagen disease, or intensive exercise, but incidence is low. In particular, rhabdomyolysis resulting from carbon monoxide poisoning is especially rare. If caught before death, carbon monoxide poisoning has been shown to cause severe muscle necrosis and severe muscle damage leading to acute renal failure. In cases of carbon-monoxide-induced rhabdomyolsis leading to acute compartment syndrome in the buttocks and sciatic nerve injury are rare. We have experience treating patients with acute compartment syndrome due to rhabdomyolysis following carbon monoxide poisoning. We report the characteristic features of muscle necrosis observed during a decompression operation and magnetic resonance imaging findings with a one-year follow-up in addition to a review of the literature.

Comparison of renal artery, soft tissue, and nerve damage after irrigated versus nonirrigated radiofrequency ablation.

PubMed

Sakakura, Kenichi; Ladich, Elena; Fuimaono, Kristine; Grunewald, Debby; O'Fallon, Patrick; Spognardi, Anna-Maria; Markham, Peter; Otsuka, Fumiyuki; Yahagi, Kazuyuki; Shen, Kai; Kolodgie, Frank D; Joner, Michael; Virmani, Renu

2015-01-01

The long-term efficacy of radiofrequency ablation of renal autonomic nerves has been proven in nonrandomized studies. However, long-term safety of the renal artery (RA) is of concern. The aim of our study was to determine if cooling during radiofrequency ablation preserved the RA while allowing equivalent nerve damage. A total of 9 swine (18 RAs) were included, and allocated to irrigated radiofrequency (n=6 RAs, temperature setting: 50°C), conventional radiofrequency (n=6 RAs, nonirrigated, temperature setting: 65°C), and high-temperature radiofrequency (n=6 RAs, nonirrigated, temperature setting: 90°C) groups. RAs were harvested at 10 days, serially sectioned from proximal to distal including perirenal tissues and examined after paraffin embedding, and staining with hematoxylin-eosin and Movat pentachrome. RAs and periarterial tissue including nerves were semiquantitatively assessed and scored. A total of 660 histological sections from 18 RAs were histologically examined by light microscopy. Arterial medial injury was significantly less in the irrigated radiofrequency group (depth of medial injury, circumferential involvement, and thinning) than that in the conventional radiofrequency group (P<0.001 for circumference; P=0.003 for thinning). Severe collagen damage such as denatured collagen was also significantly less in the irrigated compared with the conventional radiofrequency group (P<0.001). Nerve damage although not statistically different between the irrigated radiofrequency group and conventional radiofrequency group (P=0.36), there was a trend toward less nerve damage in the irrigated compared with conventional. Compared to conventional radiofrequency, circumferential medial damage in highest-temperature nonirrigated radiofrequency group was significantly greater (P<0.001). Saline irrigation significantly reduces arterial and periarterial tissue damage during radiofrequency ablation, and there is a trend toward less nerve damage. © 2014 American Heart Association, Inc.

Cranial nerve injury after Le Fort I osteotomy.

PubMed

Kim, J-W; Chin, B-R; Park, H-S; Lee, S-H; Kwon, T-G

2011-03-01

A Le Fort I osteotomy is widely used to correct dentofacial deformity because it is a safe and reliable surgical method. Although rare, various complications have been reported in relation to pterygomaxillary separation. Cranial nerve damage is one of the serious complications that can occur after Le Fort I osteotomy. In this report, a 19-year-old man with unilateral cleft lip and palate underwent surgery to correct maxillary hypoplasia, asymmetry and mandibular prognathism. After the Le Fort I maxillary osteotomy, the patient showed multiple cranial nerve damage; an impairment of outward movement of the eye (abducens nerve), decreased vision (optic nerve), and paraesthesia of the frontal and upper cheek area (ophthalmic and maxillary nerve). The damage to the cranial nerve was related to an unexpected sphenoid bone fracture and subsequent trauma in the cavernous sinus during the pterygomaxillary osteotomy. Copyright © 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Development of ocular viscosity characterization method.

PubMed

Shu-Hao Lu; Guo-Zhen Chen; Leung, Stanley Y Y; Lam, David C C

2016-08-01

Glaucoma is the second leading cause for blindness. Irreversible and progressive optic nerve damage results when the intraocular pressure (IOP) exceeds 21 mmHg. The elevated IOP is attributed to blocked fluid drainage from the eye. Methods to measure the IOP are widely available, but methods to measure the viscous response to blocked drainage has yet been developed. An indentation method to characterize the ocular flow is developed in this study. Analysis of the load-relaxation data from indentation tests on drainage-controlled porcine eyes showed that the blocked drainage is correlated with increases in ocular viscosity. Successful correlation of the ocular viscosity with drainage suggests that ocular viscosity maybe further developed as a new diagnostic parameter for assessment of normal tension glaucoma where nerve damage occurs without noticeable IOP elevation; and as a diagnostic parameter complimentary to conventional IOP in conventional diagnosis.

Harvesting of the sural nerve with a tendon stripper.

PubMed

Jaroszynski, G; Johnston, G H

1996-01-01

The nerve most commonly used for peripheral nerve reconstruction is the sural nerve. The nerve can be dissected free through one long calf incision, by utilizing multiple small incisions, or by using a tendon stripper. We studied 12 above-knee amputation specimens harvesting the nerve in the ways described. We found that the length of nerve harvested averaged 32, 36, and 25 cm for the open, limited open, and stripper techniques, respectively. Epineurial damage occurred with the stripper, but no perineurial damage was documented histologically. We concluded that the closed method (stripper) of harvesting sural nerve would provide quality graft material, but of unpredictable length. When reliably long segments of nerve are required, at least a limited open or an open approach for harvest is recommended.

Effect of upper extremity nerve damage on activity participation, pain, depression, and quality of life.

PubMed

Bailey, Ryan; Kaskutas, Vicki; Fox, Ida; Baum, Carolyn M; Mackinnon, Susan E

2009-11-01

To explore the relationship between upper extremity nerve damage and activity participation, pain, depression, and perceived quality of life. A total of 49 patients with upper extremity nerve damage completed standardized measures of activity participation, pain, depression, and quality of life. We analyzed scores for all subjects and for 2 diagnostic groups: patients with compressive neuropathy and patients with nerve injury (laceration, tumor, and brachial plexus injury), and explored predictors of overall quality of life. Participants had given up 21% of their previous daily activities; greater activity loss was reported in patients with nerve injury. Pain was moderate and 39% had signs of clinical depression. Physical and psychological quality of life ratings were below the norms. Activity loss was strongly associated with higher levels of depression and lower physical and psychological quality of life. Higher depression scores correlated strongly with lower overall quality of life. Greater pain correlated moderately with higher depression scores and weakly with quality of life; no statistical relationship was found between pain and physical quality of life. Activity participation and depression predicted 61% of the variance in overall quality of life in patients with nerve damage. The results of this study suggest that hand surgeons and therapists caring for patients with nerve compression and nerve injury should discuss strategies to improve activity participation, and decrease pain and depression, to improve overall effect on quality of life throughout the recovery process. Depression screening and referral when indicated should be included in the overall treatment plan for patients with upper extremity nerve damage. Prognostic IV.

Fiber-type susceptibility to eccentric contraction-induced damage of hindlimb-unloaded rat AL muscles

NASA Technical Reports Server (NTRS)

Vijayan, K.; Thompson, J. L.; Norenberg, K. M.; Fitts, R. H.; Riley, D. A.

2001-01-01

Slow oxidative (SO) fibers of the adductor longus (AL) were predominantly damaged during voluntary reloading of hindlimb unloaded (HU) rats and appeared explainable by preferential SO fiber recruitment. The present study assessed damage after eliminating the variable of voluntary recruitment by tetanically activating all fibers in situ through the motor nerve while applying eccentric (lengthening) or isometric contractions. Muscles were aldehyde fixed and resin embedded, and semithin sections were cut. Sarcomere lesions were quantified in toluidine blue-stained sections. Fibers were typed in serial sections immunostained with antifast myosin and antitotal myosin (which highlights slow fibers). Both isometric and eccentric paradigms caused fatigue. Lesions occurred only in eccentrically contracted control and HU muscles. Fatigue did not cause lesions. HU increased damage because lesioned- fiber percentages within fiber types and lesion sizes were greater than control. Fast oxidative glycolytic (FOG) fibers were predominantly damaged. In no case did damaged SO fibers predominate. Thus, when FOG, SO, and hybrid fibers are actively lengthened in chronically unloaded muscle, FOG fibers are intrinsically more susceptible to damage than SO fibers. Damaged hybrid-fiber proportions ranged between these extremes.

Influence of myelinated retinal nerve fibers on retinal vessel density measurement with AngioVue OCT angiography.

PubMed

Holló, Gábor

2016-12-01

Myelinated retinal nerve fibers (MRNF) represent an asymptomatic developmental anomaly in which myelin sheaths extend to a group of retinal nerve fibers along their intraocular portion. The additional volume of the myelin sheaths causes displacement of the axons toward the vitreous body. We investigated the effect of localized MRNF on peripapillary vessel density measurement results using optical coherence tomography (OCT) angiography. Peripapillary angioflow density measurements (PAFD, % of the analyzed retinal area) were made with the AngioVue OCT (Optovue Inc., Fremont, USA). In both cases, the predominant position of MRNF was inferonasal to the disk. Vessel density was clearly greater in the area of the MRNF than in the surrounding retina in the optic nerve head (ONH) level, but it was lower than in the surrounding retina in the retinal nerve fiber layer (RNFL) level. In the ONH level, PAFD was higher in the MRNF area than in the spatially corresponding superonasal area (Case 1: 64.6 vs. 57.6 %; Case 2: 65.8 vs. 56.3 %). In contrast, in the RNFL level, PAFD was lower in the MRNF area than in the corresponding superonasal area (Case 1: 60.1 vs. 65.4 %; Case 2: 46.5 vs. 58.5 %). Our cases show that the effect of MRNF on OCT angiography vessel density is different in the different measurement layers. Clinicians may separate decreased vessel density caused by anterior RNFL displacement in MRNF areas from that caused by nerve fiber damage in optic neuropathies by evaluating PAFD in both the ONH and RNFL levels.

Nerve Growth Factor Inhibits Sympathetic Neurons' Response to an Injury Cytokine

NASA Astrophysics Data System (ADS)

Shadiack, Annette M.; Vaccariello, Stacey A.; Sun, Yi; Zigmond, Richard E.

1998-06-01

Axonal damage to adult peripheral neurons causes changes in neuronal gene expression. For example, axotomized sympathetic, sensory, and motor neurons begin to express galanin mRNA and protein, and recent evidence suggests that galanin plays a role in peripheral nerve regeneration. Previous studies in sympathetic and sensory neurons have established that galanin expression is triggered by two consequences of nerve transection: the induction of leukemia inhibitory factor (LIF) and the reduction in the availability of the target-derived factor, nerve growth factor. It is shown in the present study that no stimulation of galanin expression occurs following direct application of LIF to intact neurons in the superior cervical sympathetic ganglion. Injection of animals with an antiserum to nerve growth factor concomitant with the application of LIF, on the other hand, does stimulate galanin expression. The data suggest that the response of neurons to an injury factor, LIF, is affected by whether the neurons still receive trophic signals from their targets.

Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

PubMed

Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

2015-12-01

During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Beneficial effects of a Cannabis sativa extract treatment on diabetes-induced neuropathy and oxidative stress.

PubMed

Comelli, Francesca; Bettoni, Isabella; Colleoni, Mariapia; Giagnoni, Gabriella; Costa, Barbara

2009-12-01

Neuropathy is the most common complication of diabetes and it is still considered to be relatively refractory to most of the analgesics. The aim of the present study was to explore the antinociceptive effect of a controlled cannabis extract (eCBD) in attenuating diabetic neuropathic pain. Repeated treatment with cannabis extract significantly relieved mechanical allodynia and restored the physiological thermal pain perception in streptozotocin (STZ)-induced diabetic rats without affecting hyperglycemia. In addition, the results showed that eCBD increased the reduced glutathione (GSH) content in the liver leading to a restoration of the defence mechanism and significantly decreased the liver lipid peroxidation suggesting that eCBD provides protection against oxidative damage in STZ-induced diabetes that also strongly contributes to the development of neuropathy. Finally, the nerve growth factor content in the sciatic nerve of diabetic rats was restored to normal following the repeated treatment with eCBD, suggesting that the extract was able to prevent the nerve damage caused by the reduced support of this neurotrophin. These findings highlighted the beneficial effects of cannabis extract treatment in attenuating diabetic neuropathic pain, possibly through a strong antioxidant activity and a specific action upon nerve growth factor. Copyright (c) 2009 John Wiley & Sons, Ltd.

Involvement of hypoglossal and recurrent laryngeal nerves on swallowing pressure.

PubMed

Tsujimura, Takanori; Suzuki, Taku; Yoshihara, Midori; Sakai, Shogo; Koshi, Naomi; Ashiga, Hirokazu; Shiraishi, Naru; Tsuji, Kojun; Magara, Jin; Inoue, Makoto

2018-05-01

Swallowing pressure generation is important to ensure safe transport of an ingested bolus without aspiration or leaving residue in the pharynx. To clarify the mechanism, we measured swallowing pressure at the oropharynx (OP), upper esophageal sphincter (UES), and cervical esophagus (CE) using a specially designed manometric catheter in anesthetized rats. A swallow, evoked by punctate mechanical stimulation to the larynx, was identified by recording activation of the suprahyoid and thyrohyoid muscles using electromyography (EMG). Areas under the curve of the swallowing pressure at the OP, UES, and CE from two trials indicated high intrasubject reproducibility. Effects of transecting the hypoglossal nerve (12N) and recurrent laryngeal nerve (RLN) on swallowing were investigated. Following bilateral hypoglossal nerve transection (Bi-12Nx), OP pressure was significantly decreased, and time intervals between peaks of thyrohyoid EMG bursts and OP pressure were significantly shorter. Decreased OP pressure and shortened times between peaks of thyrohyoid EMG bursts and OP pressure following Bi-12Nx were significantly increased and longer, respectively, after covering the hard and soft palates with acrylic material. UES pressure was significantly decreased after bilateral RLN transection compared with that before transection. These results suggest that the 12N and RLN play crucial roles in OP and UES pressure during swallowing, respectively. We speculate that covering the palates with a palatal augmentation prosthesis may reverse the reduced swallowing pressure in patients with 12N or tongue damage by the changes of the sensory information and of the contact between the tongue and a palates. NEW & NOTEWORTHY Hypoglossal nerve transection reduced swallowing pressure at the oropharynx. Covering the hard and soft palates with acrylic material may reverse the reduced swallowing function caused by hypoglossal nerve damage. Recurrent laryngeal nerve transection reduced upper esophageal sphincter negative pressure during swallowing.

A novel model for examining recovery of phonation after vocal nerve damage.

PubMed

Bhama, Prabhat K; Hillel, Allen D; Merati, Albert L; Perkel, David J

2011-05-01

Recurrent laryngeal nerve injury remains a dominant clinical issue in laryngology. To date, no animal model of laryngeal reinnervation has offered an outcome measure that can reflect the degree of recovery based on vocal function. We present an avian model system for studying recovery of learned vocalizations after nerve injury. Prospective animal study. Digital recordings of bird song were made from 11 adult male zebra finches; nine birds underwent bilateral crushing of the nerve supplying the vocal organ, and two birds underwent sham surgery. Songs from all the birds were then recorded regularly and analyzed based on temporal and spectral characteristics using computer software. Indices were calculated to indicate the degree of similarity between preoperative and postoperative song. Nerve crush caused audible differences in song quality and significant drops (P<0.05) in measured spectral and, to a lesser degree, temporal indices. Spectral indices recovered significantly (mean=43.0%; standard deviation [SD]=40.7; P<0.02), and there was an insignificant trend toward recovery of temporal index (mean=28.0%; SD=41.4; P=0.0771). In five of the nine (56%) birds, there was a greater than 50% recovery of spectral indices within a 4-week period. Two birds exhibited substantially less recovery of spectral indices and two birds had a persistent decline in spectral indices. Recovery of temporal index was highly variable as well, ranging from persistent further declines of 45.1% to recovery of 87%. Neither sham bird exhibited significant (P>0.05) differences in song after nerve crush. The songbird model system allows functional analysis of learned vocalization after surgical damage to vocal nerves. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Neurofibromatosis

MedlinePlus

... cranial nerves, which are called vestibular schwannomas or acoustic neuromas.. The tumors press on and damage neighboring ... cranial nerves, which are called vestibular schwannomas or acoustic neuromas.. The tumors press on and damage neighboring ...

Premature aging-related peripheral neuropathy in a mouse model of progeria.

PubMed

Goss, James R; Stolz, Donna Beer; Robinson, Andria Rasile; Zhang, Mingdi; Arbujas, Norma; Robbins, Paul D; Glorioso, Joseph C; Niedernhofer, Laura J

2011-08-01

Peripheral neuropathy is a common aging-related degenerative disorder that interferes with daily activities and leads to increased risk of falls and injury in the elderly. The etiology of most aging-related peripheral neuropathy is unknown. Inherited defects in several genome maintenance mechanisms cause tissue-specific accelerated aging, including neurodegeneration. We tested the hypothesis that a murine model of XFE progeroid syndrome, caused by reduced expression of ERCC1-XPF DNA repair endonuclease, develops peripheral neuropathy. Nerve conduction studies revealed normal nerve function in young adult (8 week) Ercc1(-/Δ) mice, but significant abnormalities in 20 week-old animals. Morphologic and ultrastructural analysis of the sciatic nerve from mutant mice revealed significant alterations at 20 but not 8 weeks of age. We conclude that Ercc1(-/Δ) mice have accelerated spontaneous peripheral neurodegeneration that mimics aging-related disease. This provides strong evidence that DNA damage can drive peripheral neuropathy and offers a rapid and novel model to test therapies. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Mephedrone, an Abused Psychoactive Component of “Bath Salts” and Methamphetamine Congener, Does not Cause Neurotoxicity to Dopamine Nerve Endings of the Striatum

PubMed Central

Angoa-Pérez, Mariana; Kane, Michael J.; Francescutti, Dina M.; Sykes, Katherine E.; Shah, Mrudang M.; Mohammed, Abiy M.; Thomas, David M.; Kuhn, Donald M.

2012-01-01

Mephedrone (4-methylmethcathinone) is a β-ketoamphetamine with close structural analogy to substituted amphetamines and cathinone derivatives. Abuse of mephedrone has increased dramatically in recent years and has become a significant public health problem in the US and Europe. Unfortunately, very little information is available on the pharmacological and neurochemical actions of mephedrone. In light of the proven abuse potential of mephedrone and considering its similarity to methamphetamine and methcathinone, it is particularly important to know if mephedrone shares with these agents an ability to cause damage to dopamine nerve endings of the striatum. Accordingly, we treated mice with a binge-like regimen of mephedrone (4X 20 or 40 mg/kg) and examined the striatum for evidence of neurotoxicity 2 or 7 days after treatment. While mephedrone caused hyperthermia and locomotor stimulation, it did not lower striatal levels of dopamine, tyrosine hydroxylase or the dopamine transporter under any of the treatment conditions used presently. Furthermore, mephedrone did not cause microglial activation in striatum nor did it increase glial fibrillary acidic protein levels. Taken together, these surprising results suggest that mephedrone, despite its numerous mechanistic overlaps with methamphetamine and the cathinone derivatives, does not cause neurotoxicity to dopamine nerve endings of the striatum. PMID:22191803

Sciatica

MedlinePlus

... sciatic nerve; Sciatic nerve dysfunction; Low back pain - sciatica; LBP - sciatica; Lumbar radiculopathy - sciatica ... Sciatica occurs when there is pressure or damage to the sciatic nerve. This nerve starts in the ...

Assessing the changes in the spatial stiffness of the posterior sclera as a function of IOP with air-pulse OCE

NASA Astrophysics Data System (ADS)

Singh, Manmohan; Nair, Achuth; Aglyamov, Salavat R.; Wu, Chen; Han, Zhaolong; Lafon, Ericka; Larin, Kirill V.

2017-02-01

The mechanophysiology of tissues in the posterior eye have been implicated for diseases such as myopia and glaucoma. For example, the eye-globe shape, and consequently optical axial length, can be affected by scleral stiffness. In glaucoma, an elevated intraocular pressure is the primary risk factor for glaucoma, which is the 2nd most prevalent known cause of blindness. Recent work has shown that biomechanical properties of the optic nerve are critical for the onset and progression of glaucoma because weak tissues cause large displacements in the optic nerve, causing tissue damage. In this work, we utilize air-pulse optical coherence elastography (OCE) to quantify the spatial distribution of biomechanical properties of the optic nerve, its surrounding tissues, and the posterior sclera. Air-pulse measurements were made in a grid on in situ porcine eyes in the whole eye-globe configuration as various IOPs. The OCE-measured displacement process was linked to tissue stiffness by a simple kinematic equation. The results show that the optic nerve and peripapillary sclera are much stiffer than the surrounding sclera, and the stiffness of the optic nerve and peripapillary sclera increased as a function of IOP. However, the stiffness of the surrounding sclera did not dramatically increase. Our results show that understanding the dynamics of the biomechanical properties of the eye are critical to understand the aforementioned diseases and may provide additional information for assessing visual health and integrity.

Electrophysiologic analysis of injury to cranial nerve XI during neck dissection.

PubMed

Lanisnik, Bostjan; Zargi, Miha; Rodi, Zoran

2016-04-01

Despite preservation of the accessory nerve, a considerable number of patients report partial nerve damage after modified radical neck dissection (MRND) and selective neck dissection. Accessory nerve branches for the trapezius muscle were stimulated during neck dissection, and the M wave amplitude was measured during distinct surgical phases. The accessory nerve was mapped in 20 patients. The M wave recordings indicated that major nerve damage occurred during dissection at levels IIa and IIb in the most proximal segment of the nerve. The M waves evoked from this nerve segment decreased significantly during surgery (analysis of variance; p = .001). The most significant intraoperative injury to the accessory nerve during neck dissection occurs at anatomic nerve levels IIa and IIb. © 2015 Wiley Periodicals, Inc. Head Neck 38: E372-E376, 2016. © 2015 Wiley Periodicals, Inc.

Types of neural guides and using nanotechnology for peripheral nerve reconstruction

PubMed Central

Biazar, Esmaeil; Khorasani, MT; Montazeri, Naser; Pourshamsian, Khalil; Daliri, Morteza; T, Mostafa Rezaei; B, Mahmoud Jabarvand; Khoshzaban, Ahad; K, Saeed Heidari; Jafarpour, Mostafa; Roviemiab, Ziba

2010-01-01

Peripheral nerve injuries can lead to lifetime loss of function and permanent disfigurement. Different methods, such as conventional allograft procedures and use of biologic tubes present problems when used for damaged peripheral nerve reconstruction. Designed scaffolds comprised of natural and synthetic materials are now widely used in the reconstruction of damaged tissues. Utilization of absorbable and nonabsorbable synthetic and natural polymers with unique characteristics can be an appropriate solution to repair damaged nerve tissues. Polymeric nanofibrous scaffolds with properties similar to neural structures can be more effective in the reconstruction process. Better cell adhesion and migration, more guiding of axons, and structural features, such as porosity, provide a clearer role for nanofibers in the restoration of neural tissues. In this paper, basic concepts of peripheral nerve injury, types of artificial and natural guides, and methods to improve the performance of tubes, such as orientation, nanotechnology applications for nerve reconstruction, fibers and nanofibers, electrospinning methods, and their application in peripheral nerve reconstruction are reviewed. PMID:21042546

Nerve Damage in Young Patients with Leprosy Diagnosed in an Endemic Area of the Brazilian Amazon: A Cross-Sectional Study.

PubMed

Bandeira, Sabrina Sampaio; Pires, Carla Avelar; Quaresma, Juarez Antonio Simões

2017-06-01

To describe nerve damage and its association with clinical and epidemiologic characteristics in young patients with leprosy diagnosed in an endemic area of the Brazilian Amazon. All 45 patients with leprosy younger than 15 years of age and diagnosed at a health referral unit in northern Brazil were invited to participate in a cross-sectional, descriptive, analytical study. Subjects were submitted to a templated simple neurologic examination of the peripheral nerves and answered a structured questionnaire. Of 41 cases, referral was the mode of detection in 33 participants (80.5%); 19 (46.3%) had been seen by 3 or more physicians to obtain a diagnosis, and 26 (63.4%) had received other diagnoses. The interval between the onset of symptoms and diagnosis was more than 1 year in 30 cases (73.2%). Borderline leprosy was the predominant clinical form (48.8%); 63.4% of the participants had multibacillary leprosy, 31.7% had nerve damage, and 17.1% exhibited disabilities. The following variables showed a statistically significant association (P???.05) with nerve damage at diagnosis: home visit by the community health worker, number of doctors seen, number of skin lesions (>5), and lesions along the path of nerve trunks. Centralized healthcare, a low frequency of home visits by community health workers, and the difficulty in diagnosing leprosy in children are factors that contribute to late treatment initiation and an increased risk of peripheral nerve damage. In addition, multiple skin lesions and lesions along the path of nerve trunks require rigorous monitoring. Copyright © 2017 Elsevier Inc. All rights reserved.

Direct current electrical stimulation of acupuncture needles for peripheral nerve regeneration: an exploratory case series.

PubMed

Inoue, Motohiro; Katsumi, Yasukazu; Itoi, Megumi; Hojo, Tatsuya; Nakajima, Miwa; Ohashi, Suzuyo; Oi, Yuki; Kitakoji, Hiroshi

2011-06-01

To examine the therapeutic effect of a novel therapeutic method based on electroacupuncture with intermittent direct current (DCEA) and associated adverse events in patients with peripheral nerve damage and a poor clinical prognosis. In seven older patients with peripheral nerve damage (neurapraxia 2, axonotmesis 4, neuromesis 1), an acupuncture needle connected to an anode electrode was inserted proximal to the site of the injury along the route of the nerve, while the cathode electrode was inserted into the innervated muscle, and DCEA was performed (100 Hz for 20 min, weekly). Muscular paralysis was evaluated weekly with manual muscle testing, the active range of motion of joints related to the muscular paralysis and, when necessary, needle electromyography. Adverse events were also recorded during the course of the treatment. Complete functional recovery was observed in the two cases with neurapraxia and two with axonotmesis, while one axonotmesis case achieved improvement and the other showed reinnervation potential without functional recovery. No improvement was observed in the neurotmesis case. Pigmentation of the skin where the anode needle was inserted occurred in three cases. Although there was no definite causal link, one case showed excessive formation and resorption of bone in the area close to the cathode needle site. Accelerated nerve regeneration caused by DCEA may contribute to recovery. The skin pigmentation and callus formation suggest that the shape of the anode electrode, current intensity and other factors should be examined to establish a safer treatment method.

Mental nerve paresthesia secondary to initiation of endodontic therapy: a case report

PubMed Central

Alam, Sharique; Zia, Afaf; Khan, Masood Hasan; Kumar, Ashok

2014-01-01

Whenever endodontic therapy is performed on mandibular posterior teeth, damage to the inferior alveolar nerve or any of its branches is possible. Acute periapical infection in mandibular posterior teeth may also sometimes disturb the normal functioning of the inferior alveolar nerve. The most common clinical manifestation of these insults is the paresthesia of the inferior alveolar nerve or mental nerve paresthesia. Paresthesia usually manifests as burning, prickling, tingling, numbness, itching or any deviation from normal sensation. Altered sensation and pain in the involved areas may interfere with speaking, eating, drinking, shaving, tooth brushing and other events of social interaction which will have a disturbing impact on the patient. Paresthesia can be short term, long term or even permanent. The duration of the paresthesia depends upon the extent of the nerve damage or persistence of the etiology. Permanent paresthesia is the result of nerve trunk laceration or actual total nerve damage. Paresthesia must be treated as soon as diagnosed to have better treatment outcomes. The present paper describes a case of mental nerve paresthesia arising after the start of the endodontic therapy in left mandibular first molar which was managed successfully by conservative treatment. PMID:25110646

Immunohistochemical Analysis of the Structure of Injured Peripheral Nerve Neuroma after Electrosurgical Welding Intervention.

PubMed

Korsak, A V; Chaikovskii, Yu B

2015-10-01

Immunohistochemical analysis of changes in neuroma after surgical treatment of damaged peripheral nerve with the use of high frequency electrosurgical device for high frequency current welding of soft tissues was carried out. No adverse effects of this technology and the bipolar instrument on degeneration and regeneration of damaged nerve stem were detected.

Tarsal tunnel syndrome

MedlinePlus

Tibial nerve dysfunction; Neuropathy - posterior tibial nerve; Peripheral neuropathy - tibial nerve; Tibial nerve entrapment ... Tarsal tunnel syndrome is an unusual form of peripheral neuropathy . It occurs when there is damage to the ...

Optical stimulation of the facial nerve: a surgical tool?

NASA Astrophysics Data System (ADS)

Richter, Claus-Peter; Teudt, Ingo Ulrik; Nevel, Adam E.; Izzo, Agnella D.; Walsh, Joseph T., Jr.

2008-02-01

One sequela of skull base surgery is the iatrogenic damage to cranial nerves. Devices that stimulate nerves with electric current can assist in the nerve identification. Contemporary devices have two main limitations: (1) the physical contact of the stimulating electrode and (2) the spread of the current through the tissue. In contrast to electrical stimulation, pulsed infrared optical radiation can be used to safely and selectively stimulate neural tissue. Stimulation and screening of the nerve is possible without making physical contact. The gerbil facial nerve was irradiated with 250-μs-long pulses of 2.12 μm radiation delivered via a 600-μm-diameter optical fiber at a repetition rate of 2 Hz. Muscle action potentials were recorded with intradermal electrodes. Nerve samples were examined for possible tissue damage. Eight facial nerves were stimulated with radiant exposures between 0.71-1.77 J/cm2, resulting in compound muscle action potentials (CmAPs) that were simultaneously measured at the m. orbicularis oculi, m. levator nasolabialis, and m. orbicularis oris. Resulting CmAP amplitudes were 0.3-0.4 mV, 0.15-1.4 mV and 0.3-2.3 mV, respectively, depending on the radial location of the optical fiber and the radiant exposure. Individual nerve branches were also stimulated, resulting in CmAP amplitudes between 0.2 and 1.6 mV. Histology revealed tissue damage at radiant exposures of 2.2 J/cm2, but no apparent damage at radiant exposures of 2.0 J/cm2.

Emergency management of chemical weapons injuries.

PubMed

Anderson, Peter D

2012-02-01

The potential for chemical weapons to be used in terrorism is a real possibility. Classes of chemical weapons include nerve agents, vesicants (blister agents), choking agents, incapacitating agents, riot control agents, blood agents, and toxic industrial chemicals. The nerve agents work by blocking the actions of acetylcholinesterase leading to a cholinergic syndrome. Nerve agents include sarin, tabun, VX, cyclosarin, and soman. The vesicants include sulfur mustard and lewisite. The vesicants produce blisters and also damage the upper airways. Choking agents include phosgene and chlorine gas. Choking agents cause pulmonary edema. Incapacitating agents include fentanyl and its derivatives and adamsite. Riot control agents include Mace and pepper spray. Blood agents include cyanide. The mechanism of toxicity for cyanide is blocking oxidative phosphorylation. Toxic industrial chemicals include agents such as formaldehyde, hydrofluoric acid, and ammonia.

Alcoholic neuropathy: possible mechanisms and future treatment possibilities

PubMed Central

Chopra, Kanwaljit; Tiwari, Vinod

2012-01-01

Chronic alcohol consumption produces painful peripheral neuropathy for which there is no reliable successful therapy, mainly due to lack of understanding of its pathobiology. Alcoholic neuropathy involves coasting caused by damage to nerves that results from long term excessive drinking of alcohol and is characterized by spontaneous burning pain, hyperalgesia and allodynia. The mechanism behind alcoholic neuropathy is not well understood, but several explanations have been proposed. These include activation of spinal cord microglia after chronic alcohol consumption, oxidative stress leading to free radical damage to nerves, activation of mGlu5 receptors in the spinal cord and activation of the sympathoadrenal and hypothalamo-pituitary-adrenal (HPA) axis. Nutritional deficiency (especially thiamine deficiency) and/or the direct toxic effect of alcohol or both have also been implicated in alcohol-induced neuropathic pain. Treatment is directed towards halting further damage to the peripheral nerves and restoring their normal functioning. This can be achieved by alcohol abstinence and a nutritionally balanced diet supplemented by all B vitamins. However, in the setting of ongoing alcohol use, vitamin supplementation alone has not been convincingly shown to be sufficient for improvement in most patients. The present review is focused around the multiple pathways involved in the development of peripheral neuropathy associated with chronic alcohol intake and the different therapeutic agents which may find a place in the therapeutic armamentarium for both prevention and management of alcoholic neuropathy. PMID:21988193

Analysis of the Istanbul Forensic Medicine Institute expert decisions on recurrent laryngeal nerve injuries due to thyroidectomy between 2008-2012.

PubMed

Karakaya, M Arif; Koç, Okay; Ekiz, Feza; Ağaçhan, A Feran; Göret, Nuri Emrah

2016-01-01

The aim of this study was to evaluate the approach of Forensic Medicine Institution for recurrent laryngeal nerve injuries. In addition, parameters that were taken into consideration by Forensic Medicine Institution in the differentiation of complication and malpractice were evaluated. The files of 38 patients, with recurrent laryngeal nerve injury following thyroidectomy, that were referred to Istanbul Forensic Medicine Institute with request of expert opinion between 2008-2012 were retrospectively investigated. Data regarding expert decisions, age, gender, diagnosis, hospital type, preoperative vocal cord examination, intraoperative nerve monitoring (IONM), identification of nerve injury during operation, repair of nerve during operation, and type of injury were assessed. Surgeons were found to be faulty in all files with bilateral nerve injury, however, one-sided injury files were considered as a medical complication. Twenty-one (55.2%) patients were female, and 17 (44.8%) were male, with a mean age of 35,8 in women, and 34,1 in men. None of these patients had undergone preoperative vocal cord assessment. The recurrent laryngeal nerve was intraoperatively identified in 21 (55.2%) patients, while it was not seen in 17 (44.8%) patients. IONM was not applied in any patients. There was no attempt for nerve repair during any operation. Nineteen patients had unilateral, and 19 patients had bilateral nerve damage. Bilateral recurrent laryngeal nerve injuries are considered as malpractice, when imaging or pathology reports fail to state a cause for difficulty in nerve identification.

Diabetes Care and Treatment Project: A Diabetes institute of the Walter Reed Health Care System and Joslin Telemedicine Initiative

DTIC Science & Technology

2010-09-01

expenditures in the United States with most of this cost associated with long term complications of diabetes specifically, retinopathy , nerve damage... retinopathy as a cause of severe vision loss. Nevertheless, diabetes remains the leading cause of new blindness in working-aged adults in the United... diabetic retinopathy evaluations performed by an ophthalmologist or optometrist with a dilated eye examination and the JVN system using digital video

Vaginal blood flow after radical hysterectomy with and without nerve sparing. A preliminary report.

PubMed

Pieterse, Q D; Ter Kuile, M M; Deruiter, M C; Trimbos, J B M Z; Kenter, G G; Maas, C P

2008-01-01

Radical hysterectomy with pelvic lymphadenectomy (RHL) for cervical cancer causes damage to the autonomic nerves, which are responsible for increased vaginal blood flow during sexual arousal. The aim of the study of which we now report preliminary data was to determine whether a nerve-sparing technique leads to an objectively less disturbed vaginal blood flow response during sexual stimulation. Photoplethysmographic assessment of vaginal pulse amplitude (VPA) during sexual stimulation by erotic films was performed. Subjective sexual arousal was assessed after each stimulus. Thirteen women after conventional RHL, 10 women after nerve-sparing RHL, and 14 healthy premenopausal women participated. Data were collected between January and August 2006. The main outcome measure was the logarithmically transformed mean VPA. To detect statistically significant differences in mean VPA levels between the three groups, a univariate analysis of variance was used. Mean VPA differed between the three groups (P= 0.014). The conventional group had a lower vaginal blood flow response than the control group (P= 0.016), which tended also to be lower than that of the nerve-sparing group (P= 0.097). These differences were critically dependent on baseline vaginal blood flow differences between the groups. The conventional group follows a vaginal blood flow pattern similar to postmenopausal women. Conventional RHL is associated with an overall disturbed vaginal blood flow response compared with healthy controls. Because it is not observed to the same extent after nerve-sparing RHL, it seems that the nerve-sparing technique leads to a better overall vaginal blood flow caused by less denervation of the vagina.

Inferior Alveolar Nerve Lateralization and Transposition for Dental Implant Placement. Part II: a Systematic Review of Neurosensory Complications.

PubMed

Abayev, Boris; Juodzbalys, Gintaras

2015-01-01

This article, the second in a two-part series, continues the discussion of inferior alveolar nerve lateralization/transposition for dental implant placement. The aim of this article is to review the scientific literature and clinical reports in order to analyse the neurosensory complications, risks and disadvantages of lateralization/transposition of the inferior alveolar nerve followed by implant placement in an edentulous atrophic posterior mandible. A comprehensive review of the current literature was conducted according to the PRISMA guidelines by accessing the NCBI PubMed and PMC databases, as well as academic sites and books. The articles were searched from January 1997 to July 2014. Articles in English language, which included adult patients between 18 - 80 years of age who had minimal residual bone above the mandibular canal and had undergone inferior alveolar nerve (IAN) repositioning, with minimum 6 months of follow-up, were included. A total of 21 studies were included in this review. Ten were related to IAN transposition, 7 to IAN lateralization and 4 to both transposition and lateralization. The IAN neurosensory disturbance function was present in most patients (99.47% [376/378]) for 1 to 6 months. In total, 0.53% (2/378) of procedures the disturbances were permanent. Inferior alveolar nerve repositioning is related to initial transient change in sensation in the majority of cases. The most popular causes of nerve damage are spatula-caused traction in the mucoperiosteal flap, pressure due to severe inflammation or retention of fluid around the nerve and subsequent development of transient ischemia, and mandibular body fracture.

In Situ complement activation and T-cell immunity in leprosy spectrum: An immunohistological study on leprosy lesional skin.

PubMed

Bahia El Idrissi, Nawal; Iyer, Anand M; Ramaglia, Valeria; Rosa, Patricia S; Soares, Cleverson T; Baas, Frank; Das, Pranab K

2017-01-01

Mycobacterium leprae (M. leprae) infection causes nerve damage and the condition worsens often during and long after treatment. Clearance of bacterial antigens including lipoarabinomannan (LAM) during and after treatment in leprosy patients is slow. We previously demonstrated that M. leprae LAM damages peripheral nerves by in situ generation of the membrane attack complex (MAC). Investigating the role of complement activation in skin lesions of leprosy patients might provide insight into the dynamics of in situ immune reactivity and the destructive pathology of M. leprae. In this study, we analyzed in skin lesions of leprosy patients, whether M. leprae antigen LAM deposition correlates with the deposition of complement activation products MAC and C3d on nerves and cells in the surrounding tissue. Skin biopsies of paucibacillary (n = 7), multibacillary leprosy patients (n = 7), and patients with erythema nodosum leprosum (ENL) (n = 6) or reversal reaction (RR) (n = 4) and controls (n = 5) were analyzed. The percentage of C3d, MAC and LAM deposition was significantly higher in the skin biopsies of multibacillary compared to paucibacillary patients (p = <0.05, p = <0.001 and p = <0.001 respectively), with a significant association between LAM and C3d or MAC in the skin biopsies of leprosy patients (r = 0.9578, p< 0.0001 and r = 0.8585, p<0.0001 respectively). In skin lesions of multibacillary patients, MAC deposition was found on axons and co-localizing with LAM. In skin lesions of paucibacillary patients, we found C3d positive T-cells in and surrounding granulomas, but hardly any MAC deposition. In addition, MAC immunoreactivity was increased in both ENL and RR skin lesions compared to non-reactional leprosy patients (p = <0.01 and p = <0.01 respectively). The present findings demonstrate that complement is deposited in skin lesions of leprosy patients, suggesting that inflammation driven by complement activation might contribute to nerve damage in the lesions of these patients. This should be regarded as an important factor in M. leprae nerve damage pathology.

Sympathetic block by metal clips may be a reversible operation.

PubMed

Thomsen, Lars L; Mikkelsen, Rasmus T; Derejko, Miroslawa; Schrøder, Henrik D; Licht, Peter B

2014-12-01

Thoracoscopic sympathectomy is now used routinely to treat patients with disabling primary hyperhidrosis or facial blushing. Published results are excellent, but side effects, such as compensatory sweating, are also very frequent. The surgical techniques used and the levels of targeting the sympathetic chain vary tremendously. Most surgeons transect or resect the sympathetic chain, but application of a metal clip that blocks transmission of nerve impulses in the sympathetic chain is used increasingly worldwide. This approach offers potential reversibility if patients regret surgery, but the question of reversibility remains controversial. Two recent experimental studies found severe histological signs of nerve damage 4-6 weeks after clip removal, but they only used conventional histopathological staining methods. Thoracoscopic clipping of the sympathetic trunk was performed in adult sheep, and the clip was removed thoracoscopically after 7 days. Following another 4 weeks (n = 6) or 12 weeks (n = 3), the sympathetic trunks were harvested and analysed by conventional and specific nerve tissue immunohistochemical stains (S100, neurofilament protein and synaptophysin). The contralateral sympathetic chains were used as controls. Conventional and immunohistochemical stains demonstrated severe signs of neural damage on the operated side 4 weeks after clip removal. After 12 weeks, these changes had decreased markedly and conventional histology had almost normalized. Conventional and immunohistochemical stains confirmed that application of metal clips to the sympathetic chain caused severe histological damage in the sympathetic trunk that remained visible 4 weeks after clip removal. However, after 12 weeks, these signs of damage had clearly decreased, which suggests in theory that application of metal clips to the sympathetic chain is a reversible procedure if only the observation period is prolonged. Further studies with longer periods between application and removal as well as investigations of nerve conduction should be encouraged, because we do not know whether histological reversibility at cellular level translates into physiological reversibility and possible correlation of nerve trauma with the duration of the applied clip. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Assessment of rat optic nerve damage due to microbeam radiation therapy in the treatment of glioblastomas.

PubMed

Mohamed, A; Worobec, S; Schultke, E

2008-01-01

Glioblastomas are the most common and aggressive subtype of human primary brain tumors. Due to their uncontrolled cellular proliferation, intense invasion, and lack of apoptosis, they are extremely difficult to treat. Currently, different approaches such as surgery, chemotherapy and radiation therapy have been employed as possible treatments however thus far; these treatments are not curative. Currently, microbeam radiation therapy (MRT) is being trialed in animal models of malignant brain tumors (rats) to aid in treatment. Some of the protocols tested have been shown to significantly increase survival rates. However, due to the high x-ray doses uses in MRT, the surrounding tissue of the targeted Glioblastomas may be irreversibly damaged. In previous studies, lens damage and clouding of the cornea have been observed in microbeam exposed eyes. However, to date no studies have assessed optic nerve damage. Therefore, this study examines the potential rat optic nerve damage following exposure to microbeam radiation therapy in the treatment of Glioblastomas. Although there appears to be no significant damage to the optic nerve, slight inflammation was observed within the extra ocular muscle.

[A study of sympathetic skin response to the damage of autonomic nerves function in patients with chronic N-hexane poisoning].

PubMed

Situ, Jie; Wu, Jian; Wang, Jing-lin; Zhu, De-xiang; Zhang, Jian-jie; Liu, Wei-wei; Qin, Zhuo-hui

2012-05-01

To study the sympathetic skin response (SSR) to the effects of N-hexane on autonomic nerves function in patients with chronic N-hexane poisoning. The subjects in present study included 30 controls and 37 cases with chronic N-hexane poisoning. Also 37 patients were divided into 3 subgroups (mild, moderate and severe poisoning) according to diagnostic criteria of occupational diseases. All subjects were examined by SSR test and nerve conduction velocity (NCV) test. All patients were reexamined by SSR and NCV every 1 ∼ 2 months. The differences in SSR parameters (latency, amplitude) among groups were observed. In the severe poisoning subgroup, the changes of SSR and NCV parameters (conduction velocity, amplitude) in different poisoning stages were observed. There were significant differences in SSR latency of upper extremity among groups and the significant differences in SSR amplitude of upper and lower extremity among groups (P < 0.05). No significant differences in SSR parameters were found between the adjacent groups (P > 0.05). There were significant differences in SSR latency of upper extremity during different periods and the significant differences in SSR amplitude of upper and lower extremity during different periods among all groups (P < 0.05). The change of SSR parameters consistent with that in NCV. The longest SSR latency of upper extremity and the smallest SSR amplitudes of upper and lower extremity appears 1 - 2 months earlier than that of the smallest action potential amplitude. The damage of autonomic nerves induced by N-hexane increased with poisoning progresses. The damage of autonomic nerves corresponded with the damage of myelin sheath of large myelinated nerves, but which appeared 1 - 2 months earlier than the damage of axon of large myelinated nerves. SSR test may serve as a method to detect the damage of autonomic nerves function in patients with chronic N-hexane poisoning.

Ulnar nerve damage (image)

MedlinePlus

The ulnar nerve originates from the brachial plexus and travels down arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where ...

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

PubMed Central

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 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. Results: 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. Conclusions: 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. PMID:26550216

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

PubMed

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.

Gene probe for P0 messenger RNA used to index acrylamide toxic neuropathy in rats.

PubMed

Veronesi, B; Jones, K; Gupta, S; Pringle, J; Mezei, C

1991-01-01

Cumulative exposure to the neurotoxicant acrylamide produces axonal damage in the distal ends of both central (CNS) and peripheral (PNS) nerve fibers and subsequent hind-limb paralysis. The messenger RNA which codes for the PNS myelin glycoprotein P0 (P0-mRNA) was used to monitor this toxic neuropathy in Sprague Dawley rats prior to, concurrent with, and subsequent to, ultrastructurally and immunocytochemically defined nerve damage. Rats were dosed every other day with acrylamide (50 mg/kg, IP) and sampled intermittently throughout a 4 week exposure period. Slot blot and Northern gel analyses of the proximal and distal sciatic nerve were used to determine a quantitated measure of P0-mRNA. Twenty-four hours after the first treatment, in the absence of ultrastructural damage, P0-mRNA increased 55% over control levels in the distal sciatic nerve. After 12 treatments, and concomitant with the appearance of spinal cord and PNS neuropathic damage and hindlimb dysfunction, P0-mRNA decreased 45% below control levels. Levels of P0-mRNA from rats exposed to 12 treatments of acrylamide but allowed to recover for 40 days, returned to 79% of control values to reflect the regeneration and remyelination occurring in the distal sciatic nerve. In spite of these fluctuations in levels of P0-mRNA, immunocytochemical staining of P0 protein in plastic sections of the distal sciatic nerve was present throughout all sample times. These results suggest that changes in neural specific mRNAs are sensitive to neurotoxic damage and can be used to monitor the pathogenesis of nerve degeneration.

Neuropathy in non-freezing cold injury (trench foot).

PubMed Central

Irwin, M S; Sanders, R; Green, C J; Terenghi, G

1997-01-01

Non-freezing cold injury (trench foot) is characterized, in severe cases, by peripheral nerve damage and tissue necrosis. Controversy exists regarding the susceptibility of nerve fibre populations to injury as well as the mechanism of injury. Clinical and histological studies (n = 2) were conducted in a 40-year-old man with severe non-freezing cold injury in both feet. Clinical sensory tests, including two-point discrimination and pressure, vibration and thermal thresholds, indicated damage to large and small diameter nerves. On immunohistochemical assessment, terminal cutaneous nerve fibres within the plantar skin stained much less than in a normal control whereas staining to von Willebrand factor pointed to increased vascularity in all areas. The results indicate that all nerve populations (myelinated and unmyelinated) were damaged, possibly in a cycle of ischaemia and reperfusion. Images Figure 1 a Figure 1 b Figure 2 a Figure 2 b Figure 3 a Figure 3 b PMID:9306996

An update-tissue engineered nerve grafts for the repair of peripheral nerve injuries.

PubMed

Patel, Nitesh P; Lyon, Kristopher A; Huang, Jason H

2018-05-01

Peripheral nerve injuries (PNI) are caused by a range of etiologies and result in a broad spectrum of disability. While nerve autografts are the current gold standard for the reconstruction of extensive nerve damage, the limited supply of autologous nerve and complications associated with harvesting nerve from a second surgical site has driven groups from multiple disciplines, including biomedical engineering, neurosurgery, plastic surgery, and orthopedic surgery, to develop a suitable or superior alternative to autografting. Over the last couple of decades, various types of scaffolds, such as acellular nerve grafts (ANGs), nerve guidance conduits, and non-nervous tissues, have been filled with Schwann cells, stem cells, and/or neurotrophic factors to develop tissue engineered nerve grafts (TENGs). Although these have shown promising effects on peripheral nerve regeneration in experimental models, the autograft has remained the gold standard for large nerve gaps. This review provides a discussion of recent advances in the development of TENGs and their efficacy in experimental models. Specifically, TENGs have been enhanced via incorporation of genetically engineered cells, methods to improve stem cell survival and differentiation, optimized delivery of neurotrophic factors via drug delivery systems (DDS), co-administration of platelet-rich plasma (PRP), and pretreatment with chondroitinase ABC (Ch-ABC). Other notable advancements include conduits that have been bioengineered to mimic native nerve structure via cell-derived extracellular matrix (ECM) deposition, and the development of transplantable living nervous tissue constructs from rat and human dorsal root ganglia (DRG) neurons. Grafts composed of non-nervous tissues, such as vein, artery, and muscle, will be briefly discussed.

Mephedrone, an abused psychoactive component of 'bath salts' and methamphetamine congener, does not cause neurotoxicity to dopamine nerve endings of the striatum.

PubMed

Angoa-Pérez, Mariana; Kane, Michael J; Francescutti, Dina M; Sykes, Katherine E; Shah, Mrudang M; Mohammed, Abiy M; Thomas, David M; Kuhn, Donald M

2012-03-01

Mephedrone (4-methylmethcathinone) is a β-ketoamphetamine with close structural analogy to substituted amphetamines and cathinone derivatives. Abuse of mephedrone has increased dramatically in recent years and has become a significant public health problem in the United States and Europe. Unfortunately, very little information is available on the pharmacological and neurochemical actions of mephedrone. In light of the proven abuse potential of mephedrone and considering its similarity to methamphetamine and methcathinone, it is particularly important to know if mephedrone shares with these agents an ability to cause damage to dopamine nerve endings of the striatum. Accordingly, we treated mice with a binge-like regimen of mephedrone (4 × 20 or 40 mg/kg) and examined the striatum for evidence of neurotoxicity 2 or 7 days after treatment. While mephedrone caused hyperthermia and locomotor stimulation, it did not lower striatal levels of dopamine, tyrosine hydroxylase or the dopamine transporter under any of the treatment conditions used presently. Furthermore, mephedrone did not cause microglial activation in striatum nor did it increase glial fibrillary acidic protein levels. Taken together, these surprising results suggest that mephedrone, despite its numerous mechanistic overlaps with methamphetamine and the cathinone derivatives, does not cause neurotoxicity to dopamine nerve endings of the striatum. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

Time-Dependent Impact of Irreversible Electroporation on Pancreas, Liver, Blood Vessels and Nerves: A Systematic Review of Experimental Studies.

PubMed

Vogel, J A; van Veldhuisen, E; Agnass, P; Crezee, J; Dijk, F; Verheij, J; van Gulik, T M; Meijerink, M R; Vroomen, L G; van Lienden, K P; Besselink, M G

2016-01-01

Irreversible electroporation (IRE) is a novel ablation technique in the treatment of unresectable cancer. The non-thermal mechanism is thought to cause mostly apoptosis compared to necrosis in thermal techniques. Both in experimental and clinical studies, a waiting time between ablation and tissue or imaging analysis to allow for cell death through apoptosis, is often reported. However, the dynamics of the IRE effect over time remain unknown. Therefore, this study aims to summarize these effects in relation to the time between treatment and evaluation. A systematic search was performed in Pubmed, Embase and the Cochrane Library for original articles using IRE on pancreas, liver or surrounding structures in animal or human studies. Data on pathology and time between IRE and evaluation were extracted. Of 2602 screened studies, 36 could be included, regarding IRE in liver (n = 24), pancreas (n = 4), blood vessels (n = 4) and nerves (n = 4) in over 440 animals (pig, rat, goat and rabbit). No eligible human studies were found. In liver and pancreas, the first signs of apoptosis and haemorrhage were observed 1-2 hours after treatment, and remained visible until 24 hours in liver and 7 days in pancreas after which the damaged tissue was replaced by fibrosis. In solitary blood vessels, the tunica media, intima and lumen remained unchanged for 24 hours. After 7 days, inflammation, fibrosis and loss of smooth muscle cells were demonstrated, which persisted until 35 days. In nerves, the median time until demonstrable histological changes was 7 days. Tissue damage after IRE is a dynamic process with remarkable time differences between tissues in animals. Whereas pancreas and liver showed the first damages after 1-2 hours, this took 24 hours in blood vessels and 7 days in nerves.

Upper Extremity Nerve Function and Pain in Human Volunteers with Narrow versus Wide Tourniquets.

PubMed

Kovar, Florian; Jauregui, Julio J; Specht, Stacy C; Baker, Erin; Bhave, Anil; Herzenberg, John E

2016-01-01

Nerve injury is a serious potential complication associated with clinical use of tourniquets during surgery. A novel narrow, single-use silicon ring tourniquet has been introduced, which may cause less nerve compression and provide a larger field of surgical exposure than standard wide tourniquets. We investigated both types of tourniquets in the non-dominant proximal upper arm of 15 healthy human volunteers. Pain and neurological effects were assessed during 15 minute trials with each tourniquet applied 1 week apart without anesthesia according to the manufacturers' recommendations. Median nerve function was studied using the pressure-specified sensory device, an instrumented two-point discriminator, and pain was assessed by two validated instruments. Skin sores, redness, nerve damage, or neurological complications did not occur in either group. Subjects reported more pain with the narrow tourniquet; however, measurable effect on median nerve function was the same in both groups. Tourniquet application with the narrow device was more efficient, the device was easier to use, and larger surgical field exposure was obtained. We conclude that the sensory deficit with the use of narrow tourniquets is not greater than that observed with pneumatic/wide tourniquets.

In vitro Repair of Oxidative DNA Damage by Human Nucleotide Excision Repair System: Possible Explanation for Neurodegeneration in Xeroderma Pigmentosum Patients

NASA Astrophysics Data System (ADS)

Reardon, Joyce T.; Bessho, Tadayoshi; Kung, Hsiang Chuan; Bolton, Philip H.; Sancar, Aziz

1997-08-01

Xeroderma pigmentosum (XP) patients fail to remove pyrimidine dimers caused by sunlight and, as a consequence, develop multiple cancers in areas exposed to light. The second most common sign, present in 20-30% of XP patients, is a set of neurological abnormalities caused by neuronal death in the central and peripheral nervous systems. Neural tissue is shielded from sunlight-induced DNA damage, so the cause of neurodegeneration in XP patients remains unexplained. In this study, we show that two major oxidative DNA lesions, 8-oxoguanine and thymine glycol, are excised from DNA in vitro by the same enzyme system responsible for removing pyrimidine dimers and other bulky DNA adducts. Our results suggest that XP neurological disease may be caused by defective repair of lesions that are produced in nerve cells by reactive oxygen species generated as by-products of an active oxidative metabolism.

Structure and innervation of the tusk pulp in the African elephant (Loxodonta africana)

PubMed Central

Weissengruber, GE; Egerbacher, M; Forstenpointner, G

2005-01-01

African elephants (Loxodonta africana) use their tusks for digging, carrying and behavioural display. Their healing ability following traumatic injury is enormous. Pain experience caused by dentin or pulp damage of tusks seems to be negligible in elephants. In this study we examined the pulp tissue and the nerve distribution using histology, electron microscopy and immunhistochemistry. The results demonstrate that the pulp comprises two differently structured regions. Randomly orientated collagen fibres characterize a cone-like part lying rostral to the foramen apicis dentis. Numerous nerve fibres and Ruffini endings are found within this cone. Rostral to the cone, delicate collagen fibres and large vessels are orientated longitudinally. The rostral two-thirds of the pulp are highly vascularized, whereas nerve fibres are sparse. Vessel and nerve fibre distribution and the structure of connective tissue possibly play important roles in healing and in the obviously limited pain experience after tusk injuries and pulp alteration. The presence of Ruffini endings is most likely related to the use of tusks as tools. PMID:15817106

The Bcl-2 family member BIM has multiple glaucoma-relevant functions in DBA/2J mice

PubMed Central

Harder, Jeffrey M.; Fernandes, Kimberly A.; Libby, Richard T.

2012-01-01

Axonal insult induces retinal ganglion cell (RGC) death through a BAX-dependent process. The pro-apoptotic Bcl-2 family member BIM is known to induce BAX activation. BIM expression increased in RGCs after axonal injury and its induction was dependent on JUN. Partial and complete Bim deficiency delayed RGC death after mechanical optic nerve injury. However, in a mouse model of glaucoma, DBA/2J mice, Bim deficiency did not prevent RGC death in eyes with severe optic nerve degeneration. In a subset of DBA/2J mice, Bim deficiency altered disease progression resulting in less severe nerve damage. Bim deficient mice exhibited altered optic nerve head morphology and significantly lessened intraocular pressure elevation. Thus, a decrease in axonal degeneration in Bim deficient DBA/2J mice may not be caused by a direct role of Bim in RGCs. These data suggest that BIM has multiple roles in glaucoma pathophysiology, potentially affecting susceptibility to glaucoma through several mechanisms. PMID:22833783

Skull base trauma: diagnosis and management.

PubMed

Samii, Madjid; Tatagiba, Marcos

2002-03-01

The singular anatomical relationship of the base of the skull is responsible for the particular problems that may arise after injury. Extensive dural laceration and severe neurovascular damage may accompany skull base injuries. Trauma to the anterior skull base is frequently related to the paranasal sinuses, and trauma to the middle and the posterior skull base usually affects the petrous bone. Injury to the anterior fossa including the paranasal sinuses may produce CSF leakage, damage the olfactory nerves, optic nerves, and orbita contents. Fractures may affect the carotid canal, injure the internal carotid artery and result in carotid-cavernous fistula. Trauma to the petrous bone may cause facial palsy and deafness, and CSF leakage with otorrhoea or paradoxal rhinoliquorrhoea. Trauma to the posterior fossa may lacerate the major venous sinuses, and affect the cranio-cervical stability. Each one of these injuries will need a particular strategy. Decision making for management as a whole must consider all aspects, including the fact that these injuries frequently involve polytraumatized patients. Decisions regarding the timing of surgery and the sequence of the surgical procedures must be made with great care. Modern surgical techniques and recent technologies including functional preservation of the olfactory nerves in frontobasal trauma, visual evoked potentials, assisted optic nerve decompression, facial nerve reconstruction, interventional technique for intravascular repair of vascular injuries, and recent developments in cochlea implants and brain stem implants, all contributed significantly to improve outcome and enhance the quality of life of patients. This article reviews basic principles of management of skull base trauma stressing the role of these advanced techniques.

Local Anesthetic-Induced Neurotoxicity

PubMed Central

Verlinde, Mark; Hollmann, Markus W.; Stevens, Markus F.; Hermanns, Henning; Werdehausen, Robert; Lirk, Philipp

2016-01-01

This review summarizes current knowledge concerning incidence, risk factors, and mechanisms of perioperative nerve injury, with focus on local anesthetic-induced neurotoxicity. Perioperative nerve injury is a complex phenomenon and can be caused by a number of clinical factors. Anesthetic risk factors for perioperative nerve injury include regional block technique, patient risk factors, and local anesthetic-induced neurotoxicity. Surgery can lead to nerve damage by use of tourniquets or by direct mechanical stress on nerves, such as traction, transection, compression, contusion, ischemia, and stretching. Current literature suggests that the majority of perioperative nerve injuries are unrelated to regional anesthesia. Besides the blockade of sodium channels which is responsible for the anesthetic effect, systemic local anesthetics can have a positive influence on the inflammatory response and the hemostatic system in the perioperative period. However, next to these beneficial effects, local anesthetics exhibit time and dose-dependent toxicity to a variety of tissues, including nerves. There is equivocal experimental evidence that the toxicity varies among local anesthetics. Even though the precise order of events during local anesthetic-induced neurotoxicity is not clear, possible cellular mechanisms have been identified. These include the intrinsic caspase-pathway, PI3K-pathway, and MAPK-pathways. Further research will need to determine whether these pathways are non-specifically activated by local anesthetics, or whether there is a single common precipitating factor. PMID:26959012

Local Anesthetic-Induced Neurotoxicity.

PubMed

Verlinde, Mark; Hollmann, Markus W; Stevens, Markus F; Hermanns, Henning; Werdehausen, Robert; Lirk, Philipp

2016-03-04

This review summarizes current knowledge concerning incidence, risk factors, and mechanisms of perioperative nerve injury, with focus on local anesthetic-induced neurotoxicity. Perioperative nerve injury is a complex phenomenon and can be caused by a number of clinical factors. Anesthetic risk factors for perioperative nerve injury include regional block technique, patient risk factors, and local anesthetic-induced neurotoxicity. Surgery can lead to nerve damage by use of tourniquets or by direct mechanical stress on nerves, such as traction, transection, compression, contusion, ischemia, and stretching. Current literature suggests that the majority of perioperative nerve injuries are unrelated to regional anesthesia. Besides the blockade of sodium channels which is responsible for the anesthetic effect, systemic local anesthetics can have a positive influence on the inflammatory response and the hemostatic system in the perioperative period. However, next to these beneficial effects, local anesthetics exhibit time and dose-dependent toxicity to a variety of tissues, including nerves. There is equivocal experimental evidence that the toxicity varies among local anesthetics. Even though the precise order of events during local anesthetic-induced neurotoxicity is not clear, possible cellular mechanisms have been identified. These include the intrinsic caspase-pathway, PI3K-pathway, and MAPK-pathways. Further research will need to determine whether these pathways are non-specifically activated by local anesthetics, or whether there is a single common precipitating factor.

Bilateral Glaucomatous Optic Neuropathy Caused by Eye Rubbing.

PubMed

Savastano, Alfonso; Savastano, Maria Cristina; Carlomusto, Laura; Savastano, Silvio

2015-01-01

In this report, we describe a particular condition of a 52-year-old man who showed advanced bilateral glaucomatous-like optic disc damage, even though the intraocular pressure resulted normal during all examinations performed. Visual field test, steady-state pattern electroretinogram, retinal nerve fiber layer and retinal tomographic evaluations were performed to evaluate the optic disc damage. Over a 4-year observational period, his visual acuity decreased to 12/20 in the right eye and counting fingers in the left eye. Visual fields were severely compromised, and intraocular pressure values were not superior to 14 mm Hg during routine examinations. An accurate anamnesis and the suspicion of this disease represent a crucial aspect to establish the correct diagnosis. In fact, our patient strongly rubbed his eyes for more than 10 h per day. Recurrent and continuous eye rubbing can induce progressive optic neuropathy, causing severe visual field damage similar to the pathology of advanced glaucoma.

Analysis of the Istanbul Forensic Medicine Institute expert decisions on recurrent laryngeal nerve injuries due to thyroidectomy between 2008–2012

PubMed Central

Karakaya, M. Arif; Koç, Okay; Ekiz, Feza; Ağaçhan, A. Feran; Göret, Nuri Emrah

2016-01-01

Objective: The aim of this study was to evaluate the approach of Forensic Medicine Institution for recurrent laryngeal nerve injuries. In addition, parameters that were taken into consideration by Forensic Medicine Institution in the differentiation of complication and malpractice were evaluated. Material and Methods: The files of 38 patients, with recurrent laryngeal nerve injury following thyroidectomy, that were referred to Istanbul Forensic Medicine Institute with request of expert opinion between 2008–2012 were retrospectively investigated. Data regarding expert decisions, age, gender, diagnosis, hospital type, preoperative vocal cord examination, intraoperative nerve monitoring (IONM), identification of nerve injury during operation, repair of nerve during operation, and type of injury were assessed. Results: Surgeons were found to be faulty in all files with bilateral nerve injury, however, one-sided injury files were considered as a medical complication. Twenty-one (55.2%) patients were female, and 17 (44.8%) were male, with a mean age of 35,8 in women, and 34,1 in men. None of these patients had undergone preoperative vocal cord assessment. The recurrent laryngeal nerve was intraoperatively identified in 21 (55.2%) patients, while it was not seen in 17 (44.8%) patients. IONM was not applied in any patients. There was no attempt for nerve repair during any operation. Nineteen patients had unilateral, and 19 patients had bilateral nerve damage. Conclusion: Bilateral recurrent laryngeal nerve injuries are considered as malpractice, when imaging or pathology reports fail to state a cause for difficulty in nerve identification. PMID:26985157

Nerve Blocks

MedlinePlus

... turn off" a pain signal along a specific distribution of nerve. Imaging guidance may be used to place the needle in the most appropriate location for maximum benefit. A nerve block may allow a damaged nerve time to heal, provide temporary pain relief and help ...

Unintentional recurrent laryngeal nerve injuries following thyroidectomy: Is it the surgeon who pays the bill?

PubMed

Gambardella, C; Polistena, A; Sanguinetti, A; Patrone, R; Napolitano, S; Esposito, D; Testa, D; Marotta, V; Faggiano, A; Calò, P G; Avenia, N; Conzo, G

2017-05-01

Thyroidectomy is one of the most common intervention in general surgery and, after the turn of the century, its rate has sharply increased, along with a worldwide increased incidence of differentiated thyroid cancers. Therefore, injuries of the recurrent laryngeal nerve have become one of the most frequent cause of surgical malpractice claims, mostly following surgery for benign pathology. Even if the incidence of definitive paralysis is generally lower than 3%, during the last 20 years in Italy, the number of claims for damages has sharply raised. As a consequence, a lot of defensive medicine has been caused by this issue, and a witch-hunt has been accordingly triggered, so determining mostly a painful and lasting frustration for the surgeons, who sometimes are compelled to pay a lot of money for increasing insurance premiums and lawyers fees. Recurrent laryngeal nerve injury should be considered as a potentially catastrophic predictable but not preventable event, rather than the result of a surgical mistake. Purposes of the Authors are analyzing incidence, conditions of risk, and mechanisms of recurrent laryngeal nerve injuries, underlining notes of surgical technique and defining medical practice recommendations useful to reduce the risk of malpractice lawsuits and judgments against surgeons. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Electrophysiological follow-up of patients with chronic peripheral neuropathy induced by occupational intoxication with n-hexane.

PubMed

Wang, Cheng; Chen, Shijiu; Wang, Zengtao

2014-09-01

The aim of this study is to characterize and dynamically monitor the progress of peripheral neuropathy induced by n-hexane by electromyography and nerve conduction velocity (NCV-EMG). Twenty-five patients with n-hexane poisoning from an electronic company were investigated in the year 2009. The occupational history of these workers was collected, and toxic substance exposure was identified. Neurologic inspection and regular NCV-EMG inspection were performed for all patients upon hospital admission and after 3, 6, and 12 months of treatment. NCV-EMG results shown that patients with n-hexane poisoning have simultaneous damage on motor and sensory nerves, of which sensory nerve damage was more severe. Motor nerves of the lower limbs were severe damaged than those of the upper limbs; whereas injury of sensory nerve in the upper limbs was more severe than that of the lower limbs. After treatment, clinical signs and symptoms of the patients were significantly improved. NCV-EMG result showed a delayed worsening at 3 months then gradually recovered after 12 months. Recovery of the motor nerve was better compared with sensory nerve, with upper limbs faster than that of the lower limbs.

Facial nerve palsy due to birth trauma

MedlinePlus

Seventh cranial nerve palsy due to birth trauma; Facial palsy - birth trauma; Facial palsy - neonate; Facial palsy - infant ... An infant's facial nerve is also called the seventh cranial nerve. It can be damaged just before or at the time of delivery. ...

Imaging of the optic nerve and retinal nerve fiber layer: an essential part of glaucoma diagnosis and monitoring.

PubMed

Kotowski, Jacek; Wollstein, Gadi; Ishikawa, Hiroshi; Schuman, Joel S

2014-01-01

Because glaucomatous damage is irreversible early detection of structural changes in the optic nerve head and retinal nerve fiber layer is imperative for timely diagnosis of glaucoma and monitoring of its progression. Significant improvements in ocular imaging have been made in recent years. Imaging techniques such as optical coherence tomography, scanning laser polarimetry and confocal scanning laser ophthalmoscopy rely on different properties of light to provide objective structural assessment of the optic nerve head, retinal nerve fiber layer and macula. In this review, we discuss the capabilities of these imaging modalities pertinent for diagnosis of glaucoma and detection of progressive glaucomatous damage and provide a review of the current knowledge on the clinical performance of these technologies. Copyright © 2014 Elsevier Inc. All rights reserved.

Recent advances in laser in situ keratomileusis-associated dry eye.

PubMed

Xie, Wenjia

2016-03-01

Dry eye is the most common complication after laser in situ keratomileusis (LASIK). The major cause of LASIK-associated dry eye is corneal nerve damage. Early identification and treatment of post-operative dry eye are essential to prevent further ocular surface damage. This article reviews the recent studies of LASIK-associated dry eye, including clinical features, aetiology, risk factors, evaluations and treatment. The applications of novel technologies in LASIK-associated dry eye evaluation like anterior segment spectral-domain optical coherence tomography (SD-OCT) and corneal confocal microscopy are also introduced in this review. © 2016 Optometry Australia.

NOVELTIES IN MEDICAL TREATMENT OF GLAUCOMA

PubMed Central

Cornel, Ştefan; Mihaela, Timaru Cristina; Adriana, Iliescu Daniela; Mehdi, Batras; Algerino, De Simone

2015-01-01

The purpose of this study is to review the current medical treatment and the new and better alternatives for patients with glaucoma. Glaucoma refers to a group of related eye disorders that have in common an optic neuropathy associated with visual function loss. It is one of the leading causes of irreversible blindness worldwide. Glaucoma can damage vision gradually so it may not be noticed until the disease is at an advanced stage. Early diagnosis and treatment can minimize or prevent optic nerve damage and limit glaucoma-related vision loss. Nowadays, research continues for the improvement of current medical treatment. PMID:26978866

Age-dependent loss of cholinergic neurons in learning and memory-related brain regions and impaired learning in SAMP8 mice with trigeminal nerve damage.

PubMed

He, Yifan; Zhu, Jihong; Huang, Fang; Qin, Liu; Fan, Wenguo; He, Hongwen

2014-11-15

The tooth belongs to the trigeminal sensory pathway. Dental damage has been associated with impairments in the central nervous system that may be mediated by injury to the trigeminal nerve. In the present study, we investigated the effects of damage to the inferior alveolar nerve, an important peripheral nerve in the trigeminal sensory pathway, on learning and memory behaviors and structural changes in related brain regions, in a mouse model of Alzheimer's disease. Inferior alveolar nerve transection or sham surgery was performed in middle-aged (4-month-old) or elderly (7-month-old) senescence-accelerated mouse prone 8 (SAMP8) mice. When the middle-aged mice reached 8 months (middle-aged group 1) or 11 months (middle-aged group 2), and the elderly group reached 11 months, step-down passive avoidance and Y-maze tests of learning and memory were performed, and the cholinergic system was examined in the hippocampus (Nissl staining and acetylcholinesterase histochemistry) and basal forebrain (choline acetyltransferase immunohistochemistry). In the elderly group, animals that underwent nerve transection had fewer pyramidal neurons in the hippocampal CA1 and CA3 regions, fewer cholinergic fibers in the CA1 and dentate gyrus, and fewer cholinergic neurons in the medial septal nucleus and vertical limb of the diagonal band, compared with sham-operated animals, as well as showing impairments in learning and memory. Conversely, no significant differences in histology or behavior were observed between middle-aged group 1 or group 2 transected mice and age-matched sham-operated mice. The present findings suggest that trigeminal nerve damage in old age, but not middle age, can induce degeneration of the septal-hippocampal cholinergic system and loss of hippocampal pyramidal neurons, and ultimately impair learning ability. Our results highlight the importance of active treatment of trigeminal nerve damage in elderly patients and those with Alzheimer's disease, and indicate that tooth extraction should be avoided in these populations.

Sex differences in the branching position of the nerve to the abductor digiti minimi muscle: an anatomical study of cadavers.

PubMed

Mizuno, Daisuke; Naito, Munekazu; Hayashi, Shogo; Ohmichi, Yusuke; Ohmichi, Mika; Nakano, Takashi

2015-01-01

The nerve to the abductor digiti minimi muscle (ADMM nerve) is the first branch of the lateral plantar nerve or originates directly from the posterior tibial nerve. Damage to the ADMM nerve is a cause of heel pain and eventually results in ADMM atrophy. It is known that ADMM atrophy occurs more often in females than in males, and the reason remains unclear. This study aimed to explore sex differences in the branching pattern, position, and angle of the ADMM nerve. Forty-two cadavers (20 males, 22 females) were dissected at Aichi Medical University between 2011 and 2015. Cases of foot deformity or atrophy were excluded and 67 ft (30 male, 37 female) were examined to assess the branching pattern, position, and angle of the ADMM nerve. The branching positions of the ADMM nerve were superior to the malleolar-calcaneal axis (MCA) in 37 ft (55 %), on the MCA in 10 ft (15 %), and inferior to the MCA in 20 ft (30 %). There was no case among male feet in which the ADMM nerve branched inferior to the MCA, whereas this pattern was observed in 19 of 37 female feet (51 %). The branching position of the ADMM nerve was significantly closer to the MCA in female feet than in male feet. There were no significant sex differences in the branching pattern and angle of the ADMM nerve. The ADMM nerve sometimes branches off inferior to the MCA in females, but not in males. This difference may be the reason for the more frequent occurrence of ADMM atrophy in females than in males.

Vagus Nerve Stimulation Delivered During Motor Rehabilitation Improves Recovery in a Rat Model of Stroke

PubMed Central

Khodaparast, Navid; Hays, Seth A.; Sloan, Andrew M.; Fayyaz, Tabbassum; Hulsey, Daniel R.; Rennaker, Robert L.; Kilgard, Michael P.

2014-01-01

Neural plasticity is widely believed to support functional recovery following brain damage. Vagus nerve stimulation paired with different forelimb movements causes long-lasting map plasticity in rat primary motor cortex that is specific to the paired movement. We tested the hypothesis that repeatedly pairing vagus nerve stimulation with upper forelimb movements would improve recovery of motor function in a rat model of stroke. Rats were separated into three groups: vagus nerve stimulation during rehab, vagus nerve stimulation after rehab, and rehab alone. Animals underwent 4 training stages: shaping (motor skill learning), pre-lesion training, post-lesion training, and therapeutic training. Rats were given a unilateral ischemic lesion within motor cortex and implanted with a left vagus nerve cuff. Animals were allowed one week of recovery before post-lesion baseline training. During the therapeutic training stage, rats received vagus nerve stimulation paired with each successful trial. All seventeen trained rats demonstrated significant contralateral forelimb impairment when performing a bradykinesia assessment task. Forelimb function was recovered completely to pre-lesion levels when vagus nerve stimulation was delivered during rehab training. Alternatively, intensive rehab training alone (without stimulation) failed to restore function to pre-lesion levels. Delivering the same amount of stimulation after rehab training did not yield improvements compared to rehab alone. These results demonstrate that vagus nerve stimulation repeatedly paired with successful forelimb movements can improve recovery after motor cortex ischemia and may be a viable option for stroke rehabilitation. PMID:24553102

Genetic linkage of autosomal dominant juvenile glaucoma to 1q21-q31 in three affected pedigrees

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiggs, J.L.; Paglinauan, C.; Fine, A.

1994-05-15

Glaucoma is a common disorder that results in irreversible damage to the optic nerve, causing absolute blindness. In most cases, the optic nerve is damaged by an elevation of the intraocular pressure that is the result of an abnormality in the normal drainage function of the trabecular meshwork. A family history of glaucoma is an important risk factor for the disease, suggesting that genetic defects predisposing to this condition are likely. Three pedigrees segregating an autosomal dominant juvenile glaucoma demonstrated significant linkage to a group of closely spaced markers on chromosome 1. These results confirm the initial mapping of thismore » disease and suggest that this region on chromosome 1 contains an important locus for juvenile glaucoma. The authors describe recombination events that improve the localization of the responsible gene, reducing the size of the candidate region from 30 to 12 cM. 27 refs., 2 figs., 1 tab.« less

[Combined surgical and physical treatment in traumatic painful syndromes of the cervical spine].

PubMed

Stachowski, B; Kaczmarek, J; Nosek, A; Kocur, L

1976-01-01

Clinical observations suggest the need for changing therapeutic management to a more active one in cases of cervical spine injury with damage to the spinal cord and nerve roots or brachial plexus. In 248 patients with these injuries treated initially conservatively the incidence of cervicobrachial pain was analysed. Neuralgic pains were present in 31.5% of cases, causalgic pains in 2.4% and sympathalgic pains in 2%. Conservative treatment conducted in these patients (89 cases) during many months after trauma had no effect on return of mobility. Long-term application of physioterapy prevented only temporarily the development of trophic changes and only partially relieved pains. Only surgical decompression of the spinal cord or spinal nerves with stabilization of damaged vertebrae caused disappearance of painful syndromes and improvement in the motor activity of the extremities. These observations show that early surgical intervention for decompression of the spinal cord, roots or brachial plexus should be advocated in these cases.

Neuro-ophthalmological approach to facial nerve palsy.

PubMed

Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

2015-01-01

Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell's palsy, Ramsay-Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell's palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell's palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell's phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell's palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration with synkinesis. FNP after acoustic neuroma surgery remains the most common indication for FN rehabilitation.

[Cranial nerve damage after neuroaxial methods of anesthesia in puerperas].

PubMed

Floka, S E; Shifman, E M

2007-01-01

The paper describes cranial nerve damage, a rare complication of neuroaxial anesthesia in obstetric care. In the literature, there are summarized data on 17 cases of neurological deficit developing after subarachnoidal or epidural anesthesia in puerperas. The etiological and pathogenetic factors of the above complications may be suggested to be the high disposition of a local anesthetic, arterial hypotension due to neuroaxial anesthetics, the outflow of cerebrospinal fluid after pachymeningeal puncture (including after unintended puncture during epidural anesthesia), and ischemic injury after the blood packing performed to relieve postpuncture headache. Closer consideration of these risk factors seems to reduce the incidence of cranial nerve damage in puerperas.

[Localized invasive intracranial aspergillosis with multiple cranial nerve failure -- case report and review of the literature].

PubMed

Winkler, F; Seelos, K; Hempel, J M; Pfister, H-W

2002-12-01

Contrary to the more frequent hematogenously spread cerebral aspergillosis, localized invasive intracranial aspergillosis is a fungal infection that can also occur in patients who are not severely immunosuppressed. This illness can be effectively treated in some of these patients by early and rigorous therapy. Localized invasion of the fungus, generally from one of the nasal sinuses, causes intracranial growth mainly along the base of the skull and larger vessels,where fibrous, granulomatous tissue develops. This generally leads to damage of the cranial nerves (primarily I-VI) as well as localized pain syndromes. We report on the clinical course documented by MRI of a patient with localized invasive intracranial aspergillosis who had multiple failure of cranial nerves following surgery for an aspergilloma of the maxillary sinus. Clinical course, imaging findings, and treatment of the illness are discussed with a review of the relevant literature.

[Polyneuropathy in diabetes type 1].

PubMed

Wilczyńska, Małgorzata

2002-01-01

Diabetic neuropathy is a clinical state of nerve damage caused by hyperglicaemia, raised activation of polyol pathway, oxydative stress, changes in endoneurial arteries and myelinated fibres. Patient complains of pain and paresthesiae in hands and limbs. The feelings of pain, temperature, touch, vibration are significantly reduced. The changes may also concern cranial nerves (IIII, IV, VI, VII), intracostal nerves, hands and limbs (Garland and Tavemer syndrome). Autonomic neuropathy concerns the impairment of autonomic functions of cardio-vascular, gastro-intestinal, uro-genital and other systems. The treatment concerns the improvement of diabetes metabolic control. Antiinflammatory antisteroid drugs are widely used but their usefulness is limited. Antidepressive drugs are the most often used group. The improvement is observed after 6 months of treatment. The side effects - orthostatic hypotension, heart rhythm disturbation and obstipation are harmful for the patients with coronary heart disease. In the cases of persistent pain the oral antiepileptic drugs may be used or cream with capsaicin for skin surface.

Current perspective of neuroprotection and glaucoma

PubMed Central

Tian, Kailin; Shibata-Germanos, Shannon; Pahlitzsch, Milena; Cordeiro, M Francesca

2015-01-01

Glaucoma is the second leading cause of blindness worldwide and is most notably characterized by progressive optic nerve atrophy and advancing loss of retinal ganglion cells (RGCs). The main concomitant factor is the elevated intraocular pressure (IOP). Existing treatments are focused generally on lowering IOP. However, both RGC loss and optic nerve atrophy can independently occur with IOP at normal levels. In recent years, there has been substantial progress in the development of neuroprotective therapies for glaucoma in order to restore vital visual function. The present review intends to offer a brief insight into conventional glaucoma treatments and discuss exciting current developments of mostly preclinical data in novel neuroprotective strategies for glaucoma that include recent advances in noninvasive diagnostics going beyond IOP maintenance for an enhanced global view. Such strategies now target RGC loss and optic nerve damage, opening a critical therapeutic window for preventative monitoring and treatment. PMID:26635467

Voice changes after thyroidectomy without recurrent laryngeal nerve injury.

PubMed

Sinagra, Diego L; Montesinos, Manuel R; Tacchi, Verónica A; Moreno, Julio C; Falco, Jorge E; Mezzadri, Norberto A; Debonis, Daniel L; Curutchet, H Pablo

2004-10-01

Injury of the inferior laryngeal nerve is not the only cause of voice alteration after thyroidectomy; many patients notice minimal changes immediately after operation, without evidence of inferior laryngeal nerve damage. We hypothesized that there may be other causes for voice modification, such as injuries of the superior laryngeal nerve, prethyroid strap muscles, and cricothyroid muscles. We describe voice changes after total thyroidectomy, without inferior laryngeal nerve injury, using a computer program to objectively compare different patterns of voice. Forty-six consecutive patients who underwent total thyroidectomy were studied between March 1997 and December 1999. Acoustic voice analysis was performed preoperatively and at the second, fourth, and sixth postoperative months using a microphone adapted to a personal computer. Parameters measured were intensity of the voice (Shimmer) and fundamental frequency (Fo). No complications occurred during operation or in the postoperative period. Voice fatigue during phonation was the most common symptom after thyroidectomy. Forty patients (87%) stated that their voices had changed since the operation, and common complaints were voice alteration while speaking loudly, changes in voice pitch, and voice disorder while singing. Changes in the Fo and Shimmer values in smokers versus nonsmokers were similar (Fo overall, p = 0.56; Shimmer overall, p = 0.66), as were the same parameters in benign and malignant pathologies (Fo overall, p = 0.66; Shimmer overall, p = 0.67). Voice changes after uncomplicated thyroidectomy occur and can be objectively measured. This is important in the preoperative counseling of patients before thyroidectomy, for ethical and legal purposes.

Effect of optic neuritis on progressive axonal damage in multiple sclerosis patients.

PubMed

Garcia-Martin, E; Pueyo, V; Ara, J R; Almarcegui, C; Martin, J; Pablo, L; Dolz, I; Sancho, E; Fernandez, F J

2011-07-01

The objective of this research was to study the effect of optic neuritis (ON) on axonal damage in multiple sclerosis (MS) patients. Specifically, we compared changes over 2 years in the retinal nerve fibre layer (RNFL) between affected and contralateral eyes in MS patients with a prior history of ON. Thirty-four patients with one unilateral definitive episode of ON were included and underwent a complete ophthalmic examination, optical coherence tomography (OCT), scanning laser polarimetry, visual evoked potentials (VEP) and pattern electroretinogram (pERG). All patients were re-evaluated at 12 and 24 months. Parameters were compared between ON-affected and contralateral eyes in an initial exploration and over the course of the follow-up. Correlations between parameter changes were analysed. RNFL thickness and functional parameters showed more affection in ON eyes (p ≤ 0.05), but changes in measurements during the study were similar between both groups of eyes. Progressive axonal loss can be detected in the optic nerve, but ON is not a risk factor for increased chronic damage in MS patients without ophthalmic relapses. Loss of the RNFL is caused by progressive degeneration associated with the disease.

Poly(ADP-ribose) polymerase inhibition reveals a potential mechanism to promote neuroprotection and treat neuropathic pain.

PubMed

Komirishetty, Prashanth; Areti, Aparna; Gogoi, Ranadeep; Sistla, Ramakrishna; Kumar, Ashutosh

2016-10-01

Neuropathic pain is triggered by the lesions to peripheral nerves which alter their structure and function. Neuroprotective approaches that limit the pathological changes and improve the behavioral outcome have been well explained in different experimental models of neuropathy but translation of such strategies to clinics has been disappointing. Experimental evidences revealed the role of free radicals, especially peroxynitrite after the nerve injury. They provoke oxidative DNA damage and consequent over-activation of the poly(ADP-ribose) polymerase (PARP) upregulates pro-inflammatory pathways, causing bioenergetic crisis and neuronal death. Along with these changes, it causes mitochondrial dysfunction leading to neuronal apoptosis. In related preclinical studies agents that neutralize the free radicals and pharmacological inhibitors of PARP have shown benefits in treating experimental neuropathy. This article reviews the involvement of PARP over-activation in trauma induced neuropathy and therapeutic significance of PARP inhibitors in the experimental neuropathy and neuropathic pain.

A combined deficiency of vitamins E and C causes severe central nervous system damage in guinea pigs.

PubMed

Burk, Raymond F; Christensen, Joani M; Maguire, Mark J; Austin, Lori M; Whetsell, William O; May, James M; Hill, Kristina E; Ebner, Ford F

2006-06-01

A short period of combined deficiency of vitamins E and C causes profound central nervous system (CNS) dysfunction in guinea pigs. For this report, CNS histopathology was studied to define the nature and extent of injury caused by this double deficiency. Weanling guinea pigs were fed a vitamin E-deficient or -replete diet for 14 d. Then vitamin C was withdrawn from the diet of some guinea pigs. Four diet groups were thus formed: replete, vitamin E deficient, vitamin C deficient, and both vitamin E and C deficient. From 5 to 11 d after institution of the doubly deficient diet, 9 of 12 guinea pigs developed paralysis, and 2 more were found dead. The remaining guinea pig in the doubly deficient group and all animals in the other 3 groups survived without clinical impairment until the experiment was terminated at 13-15 d. Brains and spinal cords were serially sectioned and stained for examination. Only the combined deficiency produced damage in the CNS. The damage consisted mainly of nerve cell death, axonal degeneration, vascular injury, and associated glial cell responses. The spinal cord and the ventral pons in the brainstem were most severely affected, often exhibiting asymmetric cystic lesions. Several features of the lesions suggest that the primary damage was to blood vessels. These results indicate that the paralysis and death caused by combined deficiency of vitamins E and C in guinea pigs is caused by severe damage in the brainstem and spinal cord.

Neurotrophic factor intervention restores auditory function in deafened animals

NASA Astrophysics Data System (ADS)

Shinohara, Takayuki; Bredberg, Göran; Ulfendahl, Mats; Pyykkö, Ilmari; Petri Olivius, N.; Kaksonen, Risto; Lindström, Bo; Altschuler, Richard; Miller, Josef M.

2002-02-01

A primary cause of deafness is damage of receptor cells in the inner ear. Clinically, it has been demonstrated that effective functionality can be provided by electrical stimulation of the auditory nerve, thus bypassing damaged receptor cells. However, subsequent to sensory cell loss there is a secondary degeneration of the afferent nerve fibers, resulting in reduced effectiveness of such cochlear prostheses. The effects of neurotrophic factors were tested in a guinea pig cochlear prosthesis model. After chemical deafening to mimic the clinical situation, the neurotrophic factors brain-derived neurotrophic factor and an analogue of ciliary neurotrophic factor were infused directly into the cochlea of the inner ear for 26 days by using an osmotic pump system. An electrode introduced into the cochlea was used to elicit auditory responses just as in patients implanted with cochlear prostheses. Intervention with brain-derived neurotrophic factor and the ciliary neurotrophic factor analogue not only increased the survival of auditory spiral ganglion neurons, but significantly enhanced the functional responsiveness of the auditory system as measured by using electrically evoked auditory brainstem responses. This demonstration that neurotrophin intervention enhances threshold sensitivity within the auditory system will have great clinical importance for the treatment of deaf patients with cochlear prostheses. The findings have direct implications for the enhancement of responsiveness in deafferented peripheral nerves.

Photobiomodulation induces antinociception, recovers structural aspects and regulates mitochondrial homeostasis in peripheral nerve of diabetic mice.

PubMed

da Silva Oliveira, Victória R; Cury, Diego P; Yamashita, Laura B; Esteca, Marcos V; Watanabe, Ii-Sei; Bergmann, Yoko Fee; Toniolo, Elaine F; Dale, Camila S

2018-05-11

Diabetic peripheral neuropathy (DPN) is a nervous disorder caused by diabetes mellitus, affecting about 50% of patients in clinical medicine. Chronic pain is one of the major and most unpleasant symptoms developed by those patients, and conventional available treatments for the neuropathy, including the associated pain, are still unsatisfactory and benefit only a small number of patients. Photobiomodulation (PBM) has been gaining clinical acceptance once it is able to promote early nerve regeneration resulting in significant improvement in peripheral nerves disabilities. In this work, the effects of PBM (660 nm, 30 mW, 1.6 J/cm 2 , 0.28 cm 2 , 15 s in a continuous frequency) on treating DPN-induced pain and nerve damage were evaluated in an experimental model of diabetic-neuropathy induced by streptozotocin in mice. PBM-induced antinociception in neuropathic-pain mice was dependent on central opioids release. After 21 consecutive applications, PBM increased nerve growth factor levels and induced structural recovery increasing mitochondrial content and regulating Parkin in the sciatic nerve of DPN-mice. Taking together, these data provide new insights into the mechanisms involved in the effects of PBM-therapy emphasizing its therapeutic potential in the treatment of DPN. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Severe diffuse axon injury in chronic alcoholic rat medulla oblongata following a concussion blow.

PubMed

Luo, Jianming; Chen, Guang; Wei, Lai; Qian, Hong; Lai, Xiaoping; Wang, Dian; Lv, Junyao; Yu, Xiaojun

2014-01-01

We investigated the axonal morphological changes and expression of both tau protein and β-APP following concussion to the medulla oblongata, in a rat model of chronic alcoholism. Fifty-nine male Sprague-Dawley rats were randomly divided into EtOH, EtOH-TBI and control groups (water group, water-TBI group). To establish chronic alcoholic rats, rats were intragastrically given edible spirituous liquor twice daily. Rats also received a blow on the occipital tuberosity with an iron pendulum. Morphological changes and expression of tau and β-APP proteins in the medulla oblongata were examined. (a) Nerve fibre thickening and twisting were observed in alcoholic rats, with nerve fibre changes becoming more significant following a concussion blow, which leads to some nerve fibres fracturing. (b) Transmission electron microscopy revealed that the nerve fibre myelin became loosened and displayed lamellar separation, which became more significant following concussion. (c) The integral optical density (IOD) sum value of β-APP of the EtOH-TBI group was lower than that in the EtOH group (P < 0.05); the Tau IOD sum value of the EtOH-TBI group was higher than that in the EtOH group (P < 0.05). (a) Chronic alcoholism caused nerve fibre and neuronal morphology damage in the rat medulla oblongata, with structural damage becoming more significant following concussion. (b) Concussion changed the expression of β-APP and tau protein in chronic alcoholic rat medulla oblongata, suggesting that chronic alcoholism can lead to severe axonal injury following a concussion blow. (c) The effect of chronic alcoholism may be synergistic the concussion blow to promote animal injury and death.

Changes in the blood-nerve barrier after sciatic nerve cold injury: indications supporting early treatment

PubMed Central

Li, Hao; Jia, Jian-ping; Xu, Min; Zhang, Lei

2015-01-01

Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, the sciatic nerve on one side of Wistar rats was treated with low temperatures (3–5°C) for 2 hours. The contralateral sciatic nerve was used as a control. We assessed changes in the nerves using Evans blue as a fluid tracer and morphological methods. Excess fluid was found in the endoneurium 1 day after cold injury, though the tight junctions between cells remained closed. From 3 to 5 days after the cold injury, the fluid was still present, but the tight junctions were open. Less tracer leakage was found from 3 to 5 days after the cold injury compared with 1 day after injury. The cold injury resulted in a breakdown of the blood-nerve barrier function, which caused endoneurial edema. However, during the early period, the breakdown of the blood-nerve barrier did not include the opening of tight junctions, but was due to other factors. Excessive fluid volume produced a large increase in the endoneurial fluid pressure, prevented liquid penetration into the endoneurium from the microvasculature. These results suggest that drug treatment to patients with cold injuries should be administered during the early period after injury because it may be more difficult for the drug to reach the injury site through the microcirculation after the tissue fluid pressure becomes elevated. PMID:25878590

Injury to the Lumbar Plexus and its Branches After Lateral Fusion Procedures: A Cadaver Study.

PubMed

Grunert, Peter; Drazin, Doniel; Iwanaga, Joe; Schmidt, Cameron; Alonso, Fernando; Moisi, Marc; Chapman, Jens R; Oskouian, Rod J; Tubbs, Richard Shane

2017-09-01

Neurologic deficits from lumbar plexus nerve injuries commonly occur in patients undergoing lateral approaches. However, it is not yet clear what types of injury occur, where anatomically they are located, or what mechanism causes them. We aimed to study 1) the topographic anatomy of lumbar plexus nerves and their injuries in human cadavers after lateral transpsoas approaches to the lumbar spine, 2) the structural morphology of those injuries, and 3) the topographic anatomy of the lumbar plexus throughout the mediolateral approach corridor. Fifteen adult fresh frozen cadaveric torsos (26 sides) underwent lateral approaches (L1-L5) by experienced lateral spine surgeons. The cadavers were subsequently opened and the entire plexus dissected and examined for nerve injuries. The topographic anatomy of the lumbar plexus and its branches, their injuries, and the morphology of these injuries were documented. Fifteen injuries were found with complete or partial nerve transections (Sunderland IV and V). Injuries were found throughout the mediolateral approach corridor. At L1/2, the iliohypogastric, ilioinguinal, and subcostal nerves were injured within the psoas major muscle, the retroperitoneal space, or the outer abdominal muscles and subcutaneous tissues. Genitofemoral nerve injuries were found in the retroperitoneal space. Nerve root injuries occurred within the retroperitoneal space and psoas muscle. Femoral nerve injuries were found only within the psoas major muscle. No obturator nerve injuries occurred. Lateral approaches can lead to structural nerve damage. Knowledge of the complex plexus anatomy, specifically its mediolateral course, is critical to avoid approach-related injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

Hemifacial Spasm and Neurovascular Compression

PubMed Central

Lu, Alex Y.; Yeung, Jacky T.; Gerrard, Jason L.; Michaelides, Elias M.; Sekula, Raymond F.; Bulsara, Ketan R.

2014-01-01

Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. Its prevalence is 9.8 per 100,000 persons with an average age of onset of 44 years. The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. HFS can be divided into two types: primary and secondary. Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. Clinical examination and imaging modalities such as electromyography (EMG) and magnetic resonance imaging (MRI) are useful to differentiate HFS from other facial movement disorders and for intraoperative planning. The standard medical management for HFS is botulinum neurotoxin (BoNT) injections, which provides low-risk but limited symptomatic relief. The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. With a low rate of complications such as hearing loss, MVD remains the treatment of choice for HFS patients as intraoperative technique and monitoring continue to improve. PMID:25405219

MRI-guided Focused Ultrasound Ablation of Lumbar Medial Branch Nerve: Feasibility and Safety Study in a Swine Model

PubMed Central

Kaye, Elena A; Monette, Sebastien; Srimathveeravalli, Govindarajan; Maybody, Majid; Solomon, Stephen B; Gulati, Amitabh

2016-01-01

Purpose About 10–40% of chronic low back pain cases involve facet joints, which are commonly treated with lumbar medial branch (MB) radiofrequency neurotomy. Magnetic Resonance Imaging-guided Focused Ultrasound (MRgFUS), a non-invasive, non-ionizing ablation modality used to treat tumors, neuropathic pain and painful bone metastasis, can also be used to disrupt nerve conduction. This work’s purpose was to study the feasibility and safety of direct MRgFUS ablation of the lumbar MB nerve in acute and subacute swine models. Materials and Methods In vivo MRgFUS ablation was performed in six swine (3 acute and 3 subacute) using a clinical MRgFUS system (ExAblate 2000®; InSightec Ltd., Haifa, Israel) and 3 T MRI scanner (SIGNA; GE Healthcare, Waukesha, WI, USA) combination. Behavioral assessment was performed, and imaging and histology were used to assess the treatment. Results and Conclusions Histological analysis of the in vivo studies confirmed thermal necrosis of the MB nerve could be achieved without damaging the spinal cord or adjacent nerve roots. MRgFUS did not cause changes in the animals’ behavior and ambulation. PMID:27443328

Effects of Chemically Doped Bioactive Borate Glass on Neuron Regrowth and Regeneration.

PubMed

Gupta, Brinda; Papke, Jason B; Mohammadkhah, Ali; Day, Delbert E; Harkins, Amy B

2016-12-01

Peripheral nerve injuries present challenges to regeneration. Currently, the gold standard for nerve repair is an autograft that results in another region of the body suffering nerve damage. Previously, bioactive borate glass (BBG) has been studied in clinical trials to treat patients with non-healing wounds, and we have reported that BBG is conducive for soft tissue repair. BBG provides structural support, degrades in a non-cytotoxic manner, and can be chemically doped. Here, we tested a wide range of chemical compounds that are reported to have neuroprotective characteristics to promote regeneration of peripheral neurons after traumatic injury. We hypothesized that chemical dopants added in trace amounts to BBG would improve neuronal survival and neurite outgrowth from dorsal root ganglion (DRG) explants. We measured neurite outgrowth from whole DRG explants, and survival rates of dissociated neurons and support cells that comprise the DRG. Results show that chemically doped BBGs have differentially variable effects on neuronal survival and outgrowth, with iron, gallium, and zinc improving outgrowth of neurons, and iodine causing the most detriment to neurons. Because chemically doped BBGs support increased nerve regrowth and survival, they show promise for use in peripheral nerve regeneration.

A chronic Alzheimer's model evoked by mitochondrial poison sodium azide for pharmacological investigations.

PubMed

Szabados, Tamás; Dul, Csaba; Majtényi, Katalin; Hargitai, Judit; Pénzes, Zoltán; Urbanics, Rudolf

2004-09-23

Alzheimer's disease (AD) is a neurodegenerative disorder and accounts for 50-70% of all dementia cases affecting more than 12 million people worldwide. The primary cause of the disease is presently unknown; however, much evidence suggests the involvement of mitochondrial damage. Selective reduction of complex IV activity is present in post-mortem AD brains. Inhibition of this complex could be evoked by chronic sodium azide (NaN(3)) administration in animals. Partial inhibition of the mitochondrial respiratory chain produces free radicals, diminishes aerobic energy metabolism and causes excitotoxic damage creating a deleterious spiral causing neurodegeneration, a pathological process considered to underlie AD. In the present study SPRD rats were treated by various doses of NaN(3) (24-51 mg/kg per day) for 31 days via subcutaneously implanted osmotic minipumps. We have found the proper dose and duration of NaN(3) treatment which was able to cause easily detectable and reproducible cognitive changes. Animals receiving Na-azide doses under 45 mg/kg daily did not show cognitive deficits, but minor histopathological changes were already present. Doses above 45 mg/kg per day proved to be toxic in 4-week-long application causing mortality. NaN(3) dose of 45 mg/kg per day caused cognitive deficit in Morris water maze and passive avoidance tests and a decrease of spontaneous exploratory activity in open field. Histopathological but not biochemical changes were present: dendritic thickening, nerve cell loss, corkscrew-like dendrites and pycnotic nerve cells. The cognitive, behavioural and histopathological features were reproducible. The chronic Na-azide-induced mitochondrial poisoning is suitable for producing AD-like symptoms in rats and testing neuroprotective drug candidates by preventive or curative applications.

Diffusion Tensor Imaging Tractography Detecting Isolated Oculomotor Nerve Damage After Traumatic Brain Injury.

PubMed

Jacquesson, Timothée; Frindel, Carole; Cotton, Francois

2017-04-01

A 24-year-old woman was hit by a bus and suffered an isolated complete oculomotor nerve palsy. Computed tomography scan did not show a skull base fracture. T2*-weighted magnetic resonance imaging revealed petechial cerebral hemorrhages sparing the brainstem. T2 constructive interference in steady state suggested a partial sectioning of the left oculomotor nerve just before entering the superior orbital fissure. Diffusion tensor imaging fiber tractography confirmed a sharp arrest of the left oculomotor nerve. This recent imaging technique could be of interest to assess white fiber damage and help make a diagnosis or prognosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of the Dental Effects of Laryngopharyngeal Reflux

DTIC Science & Technology

2015-03-01

can be attributed to gastroesophageal reflux disease (GERO), a clinical disorder which is caused by chronic esophageal acid exposure. A related but... chronic acid reflux can result in mucosa I damage and sensory nerve stimulation of the esophageal tissues. This is likely the result of direct contact...extraesophageal due to mesial migration of endogenous stomach acids. These may include chest pain, sinusitis, globus, chronic cough, asthma-like symptoms

Dopamine quinones activate microglia and induce a neurotoxic gene expression profile: relationship to methamphetamine-induced nerve ending damage.

PubMed

Kuhn, Donald M; Francescutti-Verbeem, Dina M; Thomas, David M

2006-08-01

Methamphetamine (METH) intoxication leads to persistent damage of dopamine (DA) nerve endings of the striatum. Recently, we and others have suggested that the neurotoxicity associated with METH is mediated by extensive microglial activation. DA itself has been shown to play an obligatory role in METH neurotoxicity, possibly through the formation of quinone species. We show presently that DA-quinones (DAQ) cause a time-dependent activation of cultured microglial cells. Microarray analysis of the effects of DAQ on microglial gene expression revealed that 101 genes were significantly changed in expression, with 73 genes increasing and 28 genes decreasing in expression. Among those genes differentially regulated by DAQ were those often associated with neurotoxic conditions including inflammation, cytokines, chemokines, and prostaglandins. In addition, microglial genes associated with a neuronally protective phenotype were among those that were downregulated by DAQ. These results implicate DAQ as one species that could cause early activation of microglial cells in METH intoxication, manifested as an alteration in the expression of a broad biomarker panel of genes. These results also link oxidative stress, chemical alterations in DA to its quinone, and microglial activation as part of a cascade of glial-neuronal crosstalk that can amplify METH-induced neurotoxicity.

Recording nerve signals in canine sciatic nerves with a flexible penetrating microelectrode array

NASA Astrophysics Data System (ADS)

Byun, Donghak; Cho, Sung-Joon; Lee, Byeong Han; Min, Joongkee; Lee, Jong-Hyun; Kim, Sohee

2017-08-01

Objective. Previously, we presented the fabrication and characterization of a flexible penetrating microelectrode array (FPMA) as a neural interface device. In the present study, we aim to prove the feasibility of the developed FPMA as a chronic intrafascicular recording tool for peripheral applications. Approach. For recording from the peripheral nerves of medium-sized animals, the FPMA was integrated with an interconnection cable and other parts that were designed to fit canine sciatic nerves. The uniformity of tip exposure and in vitro electrochemical properties of the electrodes were characterized. The capability of the device to acquire in vivo electrophysiological signals was evaluated by implanting the FPMA assembly in canine sciatic nerves acutely as well as chronically for 4 weeks. We also examined the histology of implanted tissues to evaluate the damage caused by the device. Main results. Throughout recording sessions, we observed successful multi-channel recordings (up to 73% of viable electrode channels) of evoked afferent and spontaneous nerve unit spikes with high signal quality (SNR  >  4.9). Also, minor influences of the device implantation on the morphology of nerve tissues were found. Significance. The presented results demonstrate the viability of the developed FPMA device in the peripheral nerves of medium-sized animals, thereby bringing us a step closer to human applications. Furthermore, the obtained data provide a driving force toward a further study for device improvements to be used as a bidirectional neural interface in humans.

Accidental injury of the inferior alveolar nerve due to the extrusion of calcium hydroxide in endodontic treatment: a case report

PubMed Central

2016-01-01

During clinical endodontic treatment, we often find radiopaque filling material beyond the root apex. Accidental extrusion of calcium hydroxide could cause the injury of inferior alveolar nerve, such as paresthesia or continuous inflammatory response. This case report presents the extrusion of calcium hydroxide and treatment procedures including surgical intervention. A 48 yr old female patient experienced Calcipex II extrusion in to the inferior alveolar canal on left mandibular area during endodontic treatment. After completion of endodontic treatment on left mandibular first molar, surgical intervention was planned under general anesthesia. After cortical bone osteotomy and debridement, neuroma resection and neurorrhaphy was performed, and prognosis was observed. But no improvement in sensory nerve was seen following surgical intervention after 20 mon. A clinician should be aware of extrusion of intracanal medicaments and the possibility of damage on inferior alveolar canal. Injectable type of calcium hydroxide should be applied with care for preventing nerve injury. The alternative delivery method such as lentulo spiral was suggested on the posterior mandibular molar. PMID:26877992

Injury of the Inferior Alveolar Nerve during Implant Placement: a Literature Review

PubMed Central

Wang, Hom-Lay; Sabalys, Gintautas

2011-01-01

ABSTRACT Objectives The purpose of present article was to review aetiological factors, mechanism, clinical symptoms, and diagnostic methods as well as to create treatment guidelines for the management of inferior alveolar nerve injury during dental implant placement. Material and Methods Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were inferior alveolar nerve injury, inferior alveolar nerve injuries, inferior alveolar nerve injury implant, inferior alveolar nerve damage, inferior alveolar nerve paresthesia and inferior alveolar nerve repair. The search was restricted to English language articles, published from 1972 to November 2010. Additionally, a manual search in the major anatomy, dental implant, periodontal and oral surgery journals and books were performed. The publications there selected by including clinical, human anatomy and physiology studies. Results In total 136 literature sources were obtained and reviewed. Aetiological factors of inferior alveolar nerve injury, risk factors, mechanism, clinical sensory nerve examination methods, clinical symptoms and treatment were discussed. Guidelines were created to illustrate the methods used to prevent and manage inferior alveolar nerve injury before or after dental implant placement. Conclusions The damage of inferior alveolar nerve during the dental implant placement can be a serious complication. Clinician should recognise and exclude aetiological factors leading to nerve injury. Proper presurgery planning, timely diagnosis and treatment are the key to avoid nerve sensory disturbances management. PMID:24421983

Caloric stimulation

MedlinePlus

... differences in temperature to diagnose damage to the acoustic nerve. This is the nerve that is involved ... This test stimulates your acoustic nerve by delivering cold or warm water or air into your ear canal. When cold water or air enters your ...

Nitrotyrosine localization to dermal nerves in borderline leprosy.

PubMed

Schön, T; Hernández-Pando, R; Baquera-Heredia, J; Negesse, Y; Becerril-Villanueva, L E; Eon-Contreras, J C L; Sundqvist, T; Britton, S

2004-03-01

Nerve damage is a common and disabling feature of leprosy, with unclear aetiology. It has been reported that the peroxidizing agents of myelin lipids-nitric oxide (NO) and peroxynitrite-are produced in leprosy skin lesions. To investigate the localization of nitrotyrosine (NT)-a local end-product of peroxynitrite-in leprosy lesions where dermal nerves are affected by a granulomatous reaction. We investigated by immunohistochemistry and immunoelectron microscopy the localization of the inducible NO synthase (iNOS) and NT in biopsies exhibiting dermal nerves from patients with untreated leprosy. There were abundant NT-positive and iNOS-positive macrophages in the borderline leprosy granulomas infiltrating peripheral nerves identified by light microscopy, S-100 and neurofilament immunostaining. Immunoelectron microscopy showed NT reactivity in neurofilament aggregates and in the cell wall of Mycobacterium leprae. Our results suggest that NO and peroxynitrite could be involved in the nerve damage following borderline leprosy.

Colony Stimulating Factor-1 Receptor Expressing Cells Infiltrating the Cornea Control Corneal Nerve Degeneration in Response to HSV-1 Infection

PubMed Central

Chucair-Elliott, Ana J.; Gurung, Hem R.; Carr, Meghan M.; Carr, Daniel J. J.

2017-01-01

Purpose Herpes simplex virus type-1 (HSV-1) is a leading cause of neurotrophic keratitis, characterized by decreased or absent corneal sensation due to damage to the sensory corneal innervation. We previously reported the elicited immune response to infection contributes to the mechanism of corneal nerve regression/damage during acute HSV-1 infection. Our aim is to further establish the involvement of infiltrated macrophages in the mechanism of nerve loss upon infection. Methods Macrophage Fas-Induced Apoptosis (MAFIA) transgenic C57BL/6 mice were systemically treated with AP20187 dimerizer or vehicle (VEH), and their corneas, lymph nodes, and blood were assessed for CD45+CD11b+GFP+ cell depletion by flow cytometry (FC). Mice were ocularly infected with HSV-1 or left uninfected. At 2, 4, and/or 6 days post infection (PI), corneas were assessed for sensitivity and harvested for FC, nerve structure by immunohistochemistry, viral content by plaque assay, soluble factor content by suspension array, and activation of signaling pathways by Western blot analysis. C57BL6 mice were used to compare to the MAFIA mouse model. Results MAFIA mice treated with AP20187 had efficient depletion of CD45+CD11b+GFP+ cells in the tissues analyzed. The reduction of CD45+CD11b+GFP+ cells recruited to the infected corneas of AP20187-treated mice correlated with preservation of corneal nerve structure and function, decreased protein concentration of inflammatory cytokines, and decreased STAT3 activation despite no changes in viral content in the cornea compared to VEH-treated animals. Conclusions Our results suggest infiltrated macrophages are early effectors in the nerve regression following HSV-1 infection. We propose the neurodegeneration mechanism involves macrophages, local up-regulation of IL-6, and activation of STAT3. PMID:28903153

Neurophysiologic intraoperative monitoring of the vestibulocochlear nerve.

PubMed

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.

Prevalence of Disability and Associated Factors among Registered Leprosy Patients in All Africa Tb and Leprosy Rehabilitation and Training Centre (ALERT), Addis Ababa, Ethiopia.

PubMed

Shumet, Tigist; Demissie, Meaza; Bekele, Yonas

2015-10-01

Delay in leprosy diagnosis and treatment causes disabilities due to nerve damage, immunological reactions and bacillary infiltration. Leprosy disability leads not only to physical dysfunction and activity limitation but also disrupts social interaction of affected individuals by creating stigma and discrimination. This study was aimed at assessing leprosy disability status in patients registered at All African TB and Leprosy Rehabilitation and Training Centre. Medical records of leprosy patients registered from September 11, 2010 to September 10, 2013 G.C were reviewed. Prevalence of disability calculated, bivariate and multiple logistic regressions were used to determine crude and adjusted odds ratios with 95% confidence interval. The overall prevalence of disability was found to be 65.9% from all categories of patients (40.2% Grade I and 25.7% Grade II). The Prevalence among the new category was 62.8% (39.1% Grade 1 and 23.7% Grade 2). Those ageed above 30 years, with duration of symptoms 6-12 months and above 24 months, with sensory loss, nerve damage and reversal reaction were more likely to develop disability. In this study the prevalence of disability, both Grade I and II, is very high. Disability was associated with age, duration of symptom, sensory loss, signs of nerve damage and reversal reaction. These risk factors indicate the existence of delay in diagnosis and treatment of leprosy cases. Therefore, the national leprosy control program should investigate leprosy case detection and diagnosis system in the country and work on improving early case detection and prevention of disability.

Central nervous system (image)

MedlinePlus

... receive nerve impulses from the spinal cord and cranial nerves. The spinal cord contains the nerves that carry messages between the brain and the body. Spinal cord injury can occur when there is damage to the cells within the spinal cord or ...

Myoneural necrosis following high-frequency electrical stimulation of the cast-immobilized rabbit hindlimb

NASA Technical Reports Server (NTRS)

Friden, J.; Lieber, R. L.; Myers, R. R.; Powell, H. C.; Hargens, A. R.

1989-01-01

The morphological and physiological effects of 4 weeks of high-frequency electrical stimulation (1 h/day, 5 days/week) on cast-immobilized rabbit hindlimbs were investigated in the tibialis anterior muscle and peroneal nerve. In 2 out of 6 animals, high-frequency stimulation with immobilization caused muscle fiber death, internalization of muscle fiber nuclei, connective tissue proliferation, inflammatory response, altered fiber size distribution and variable staining intensities. The fast-twitch fibers were predominantly affected. Two of six peripheral nerves subjected to immobilization and stimulation showed severe damage. Tetanic forces were significantly reduced in the affected muscles. Therefore, the immobilization and high-frequency stimulation may be detrimental to myoneural structure and function and, thus, this combination of therapies should be applied conservatively.

Jacob's limp.

PubMed

Hoenig, L J

1997-02-01

This study describes in modern medical terms a traumatic hip injury suffered by the Biblical patriarch Jacob approximately 3,500 years ago. The case history is based on the original Hebrew text found in the Bible book of Genesis (Chapter 32:25-33) as interpreted by traditional Jewish commentaries on the Bible. Jacob sustained a hip injury in hand-to-hand combat with an adversary or through an intense physiological reaction to a prophetic vision of such a battle. He appears to have sustained neurological injury to his sciatic nerve as well as musculoskeletal damage to his hip. These injuries caused a temporary limping gait. Jacob probably sustained a neurapraxia of the sciatic nerve. The differential diagnosis of his musculoskeletal hip injury includes hip dislocation, fracture, soft tissue trauma, and articular pathology.

The Effects of Renal Denervation on Renal Hemodynamics and Renal Vasculature in a Porcine Model

PubMed Central

Verloop, Willemien L.; Hubens, Lisette E. G.; Spiering, Wilko; Doevendans, Pieter A.; Goldschmeding, Roel; Bleys, Ronald L. A. W.; Voskuil, Michiel

2015-01-01

Rationale Recently, the efficacy of renal denervation (RDN) has been debated. It is discussed whether RDN is able to adequately target the renal nerves. Objective We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology. Methods and Results We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01). In contrast, renal resistance reserve increased from 1.74 (1.28) to 1.88 (1.17) (P = 0.02) during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14%) nerves per pig were observed within a lesion area). Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05) at three weeks of follow-up. Conclusion Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN. PMID:26587981

Time-Dependent Impact of Irreversible Electroporation on Pancreas, Liver, Blood Vessels and Nerves: A Systematic Review of Experimental Studies

PubMed Central

Agnass, P.; Crezee, J.; Dijk, F.; Verheij, J.; van Gulik, T. M.; Meijerink, M. R.; Vroomen, L. G.; van Lienden, K. P.; Besselink, M. G.

2016-01-01

Introduction Irreversible electroporation (IRE) is a novel ablation technique in the treatment of unresectable cancer. The non-thermal mechanism is thought to cause mostly apoptosis compared to necrosis in thermal techniques. Both in experimental and clinical studies, a waiting time between ablation and tissue or imaging analysis to allow for cell death through apoptosis, is often reported. However, the dynamics of the IRE effect over time remain unknown. Therefore, this study aims to summarize these effects in relation to the time between treatment and evaluation. Methods A systematic search was performed in Pubmed, Embase and the Cochrane Library for original articles using IRE on pancreas, liver or surrounding structures in animal or human studies. Data on pathology and time between IRE and evaluation were extracted. Results Of 2602 screened studies, 36 could be included, regarding IRE in liver (n = 24), pancreas (n = 4), blood vessels (n = 4) and nerves (n = 4) in over 440 animals (pig, rat, goat and rabbit). No eligible human studies were found. In liver and pancreas, the first signs of apoptosis and haemorrhage were observed 1–2 hours after treatment, and remained visible until 24 hours in liver and 7 days in pancreas after which the damaged tissue was replaced by fibrosis. In solitary blood vessels, the tunica media, intima and lumen remained unchanged for 24 hours. After 7 days, inflammation, fibrosis and loss of smooth muscle cells were demonstrated, which persisted until 35 days. In nerves, the median time until demonstrable histological changes was 7 days. Conclusions Tissue damage after IRE is a dynamic process with remarkable time differences between tissues in animals. Whereas pancreas and liver showed the first damages after 1–2 hours, this took 24 hours in blood vessels and 7 days in nerves. PMID:27870918

Mephedrone Does not Damage Dopamine Nerve Endings of the Striatum but Enhances the Neurotoxicity of Methamphetamine, Amphetamine and MDMA

PubMed Central

Angoa-Pérez, Mariana; Kane, Michael J.; Briggs, Denise I.; Francescutti, Dina M.; Sykes, Catherine E.; Shah, Mrudang M.; Thomas, David M.; Kuhn, Donald M.

2012-01-01

Mephedrone (4-methylmethcathinone) is a β-ketoamphetamine stimulant drug of abuse with close structural and mechanistic similarities to methamphetamine. One of the most powerful actions associated with mephedrone is the ability to stimulate dopamine (DA) release and block its reuptake through its interaction with the dopamine transporter (DAT). Although mephedrone does not cause toxicity to DA nerve endings, its ability to serve as a DAT blocker could provide protection against methamphetamine-induced neurotoxicity like other DAT inhibitors. To test this possibility, mice were treated with mephedrone (10, 20 or 40 mg/kg) prior to each injection of a neurotoxic regimen of methamphetamine (4 injections of 2.5 or 5.0 mg/kg at 2 hr intervals). The integrity of DA nerve endings of the striatum was assessed through measures of DA, DAT and tyrosine hydroxylase levels. The moderate to severe DA toxicity associated with the different doses of methamphetamine was not prevented by any dose of mephedrone but was, in fact, significantly enhanced. The hyperthermia caused by combined treatment with mephedrone and methamphetamine was the same as seen after either drug alone. Mephedrone also enhanced the neurotoxic effects of amphetamine and MDMA on DA nerve endings. In contrast, nomifensine protected against methamphetamine-induced neurotoxicity. Because mephedrone increases methamphetamine neurotoxicity, the present results suggest that it interacts with the DAT in a manner unlike that of other typical DAT inhibitors. The relatively innocuous effects of mephedrone alone on DA nerve endings mask a potentially dangerous interaction with drugs that are often co-abused with it, leading to heightened neurotoxicity. PMID:23205838

Closure of laryngotracheal cavity and tracheostomy for intractable aspiration secondary to radiation encephalopathy or radiation damage of cranial nerve after radiotherapy of nasopharyngeal carcinoma.

PubMed

Qu, Shenhong; Su, Zhengzhong; He, Xiaoguang; Li, Min; Li, Tianying

2006-09-01

Closure of the laryngotracheal cavity and tracheostomy is especially suitable for intractable aspiration secondary to radiation encephalopathy or damage of cranial nerve after radiation for nasopharyngeal carcinoma (NPC). To investigate the clinical value, technique, indications and contraindications of closure of the laryngotracheal cavity and tracheostomy for intractable aspiration secondary to radiation encephalopathy (REP) or radiation damage of cranial nerve after radiotherapy of NPC. Thirty patients, suffering from intractable aspiration secondary to radiotherapy for nasopharyngeal carcinoma, were treated with closure of the laryngotracheal cavity and tracheostomy and were observed for at least 1 year. Intractable aspiration and dyspnea were completely eradicated in all patients. The quality of their life was greatly improved.

Laser-activated protein solder for peripheral nerve repair

NASA Astrophysics Data System (ADS)

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.

Tibial nerve (image)

MedlinePlus

... nerve is commonly injured by fractures or other injury to the back of the knee or the lower leg. It may be affected by systemic diseases such as diabetes mellitus. The nerve can also be damaged by pressure from a tumor, abscess, or bleeding into the ...

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Escobar, Antonio S.; Ocampo, Arcelia F. M.; Hernandez, Maria G. H.

2010-05-31

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 andmore » 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<0.001 and p<000) as in the amplitude (p<000 and p<000). Groups 3 and 4, which was stimulated at 100 mA and 100 ms latency showed no statistically significant difference (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).« less

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

NASA Astrophysics Data System (ADS)

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 (p<0.001 and p<000) as in the amplitude (p<000 and p<000). Groups 3 and 4, which was stimulated at 100 mA and 100 ms latency showed no statistically significant difference (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).

Characterizing liability for cranial nerve injuries: a detailed analysis of 209 malpractice trials.

PubMed

Svider, Peter F; Sunaryo, Peter L; Keeley, Brieze R; Kovalerchik, Olga; Mauro, Andrew C; Eloy, Jean Anderson

2013-05-01

The potential for adverse events with lasting functional effects makes cranial nerve (CN) injury a target for litigation. Our objective was to comprehensively examine records of malpractice trials and detail issues influencing outcomes. Retrospective analysis. The Westlaw database (Thomson Reuters, New York, NY) was searched for jury verdict reports related to medical malpractice and CN injury. After excluding nonrelevant cases, we examined 209 trials for characteristics including nerve(s) injured, alleged causes of malpractice, demographic information, specialty, and outcome. The most commonly litigated CNs were VII (24.4%) and II (19.6%). Sixty-nine (33.0%) trials resulted in damages awarded. Outcomes varied, ranging from a 29.2% plaintiff success rate for CN XI injury to 48.4% for CN II injury. Plaintiffs had less success with increasing age. Average damages awarded were $1.7 million. The most commonly named defendants were otolaryngologists and general surgeons. Individual considerations varied but commonly included alleged deficits in informed consent (25.4%), unnecessary procedures (14.8%), undergoing additional surgery (25.8%), and untimely recognition of complications (23.9%). Malpractice trials were resolved in the defendant's favor the majority of the time. In cases where plaintiffs were successful, however, awards were considerable, averaging nearly $2 million. Factors influencing case outcome included age, location, perceived deficits in informed consent, allegedly unnecessary surgery, requiring additional surgery to repair a complication, and untimely recognition of complications. Although specific factors should be taken into consideration with each procedure, providing detailed informed consent and communicating with patients regarding expectations may minimize liability. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Diabetes and nerve damage

MedlinePlus

Diabetic neuropathy; Diabetes - neuropathy; Diabetes - peripheral neuropathy ... pubmed/27979897 . Boulton AJM, Malik RA. Diabetes mellitus: ... of peripheral nerves. In: Daroff RB, Jankovic J, Mazziotta JC, ...

Microfasciculation: a morphological pattern in leprosy nerve damage.

PubMed

Antunes, Sérgio L G; Medeiros, Mildred F; Corte-Real, Suzana; Jardim, Márcia R; Nery, José A da Costa; Hacker, Mariana A V B; Valentim, Vânia da Costa; Amadeu, Thaís Porto; Sarno, Euzenir N

2011-01-01

To study Microfasciculation, a perineurial response found in neuropathies, emphasizing its frequency, detailed morphological characteristics and biological significance in pure neural leprosy (PNL), post-treatment leprosy neuropathy (PTLN) and non-leprosy neuropathies (NLN). Morphological characteristics of microfascicles were examined via histological staining methods, immunohistochemical expression of neural markers and transmission electronmicroscopy. The detection of microfasciculation in 18 nerve biopsy specimens [12 PNL, six PTLN but not in the NLN group, was associated strongly with perineurial damage and the presence of a multibacillary inflammatory process in the nerves, particularly in the perineurium. Immunoreactivity to anti-S100 protein, anti-neurofilament, anti-nerve growth receptor and anti-myelin basic protein immunoreactivity was found within microfascicles. Ultrastructural examination of three biopsies showed that fibroblast-perineurial cells were devoid of basement membrane despite perineurial-like NGFr immunoreactivity. Morphological evidence demonstrated that multipotent pericytes from inflammation-activated microvessels could be the origin of fibroblast-perineurial cells. A microfasciculation pattern was found in 10% of leprosy-affected nerves. The microfascicles were composed predominantly of unmyelinated fibres and denervated Schwann cells (SCs) surrounded by fibroblast-perineurial cells. This pattern was found more frequently in leprosy nerves with acid-fast bacilli (AFB) and perineurial damage while undergoing an inflammatory process. Further experimental studies are necessary to elucidate microfascicle formation. © 2011 Blackwell Publishing Limited.

Optic nerve regeneration in the mouse is a complex trait modulated by genetic background

PubMed Central

Wang, Jiaxing; Li, Ying; King, Rebecca; Struebing, Felix L.

2018-01-01

Purpose The present study is designed to identify the influences of genetic background on optic nerve regeneration using the two parental strains (C57BL/6J and DBA/2J) and seven BXD recombinant inbred mouse strains. Methods To study regeneration in the optic nerve, Pten was knocked down in the retinal ganglion cells using adenoassociated virus (AAV) delivery of shRNA, and a mild inflammatory response was induced with an intravitreal injection of zymosan with CPT-cAMP. The axons of the retinal ganglion cells were damaged by optic nerve crush (ONC). Following a 12-day survival period, regenerating axons were labeled by cholera toxin B, and 2 days later, the regenerating axons within the optic nerve were examined. The number of axons at 0.5 mm and 1 mm from the crush site were counted. In addition, we measured the distance that five axons had grown down the nerve and the longest distance a single axon reached. Results The analysis revealed a considerable amount of differential axonal regeneration across the seven BXD strains and the parental strains. There was a statistically significant difference (p=0.014 Mann–Whitney U test) in the regenerative capacity in the number of axons reaching 0.5 mm from a low of 236.1±24.4 axons in the BXD102 mice to a high of 759.8±79.2 axons in the BXD29 mice. There were also statistically significant differences (p=0.014 Mann–Whitney U test) in the distance axons traveled. Looking at a minimum of five axons, the shortest distance was 787.2±46.5 µm in the BXD102 mice, and the maximum distance was 2025.5±223.3 µm in the BXD29 mice. Conclusions Differences in genetic background can have a profound effect on axonal regeneration causing a threefold increase in the number of regenerating axons at 0.5 mm from the crush site and a 2.5-fold increase in the distance traveled by at least five axons in the damaged optic nerve. PMID:29463955

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

PubMed

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

2017-07-01

Axonal damage is one of the most common pathological features of traumatic brain injury, leading to abnormalities in signal propagation for nervous systems. We present a 3D fully coupled electro-mechanical model of a nerve bundle, made with the finite element software Abaqus 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 the bundle. Compression and tension are simulated to induce damage at the nerve membrane. 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 traumatized nerve membrane. Results show greater changes in transmitting action potential in the myelinated fibre.

A novel AARS mutation in a family with dominant myeloneuropathy.

PubMed

Motley, William W; Griffin, Laurie B; Mademan, Inès; Baets, Jonathan; De Vriendt, Els; De Jonghe, Peter; Antonellis, Anthony; Jordanova, Albena; Scherer, Steven S

2015-05-19

To determine the genetic cause of neurodegeneration in a family with myeloneuropathy. We studied 5 siblings in a family with a mild, dominantly inherited neuropathy by clinical examination and electrophysiology. One patient had a sural nerve biopsy. After ruling out common genetic causes of axonal Charcot-Marie-Tooth disease, we sequenced 3 tRNA synthetase genes associated with neuropathy. All affected family members had a mild axonal neuropathy, and 3 of 4 had lower extremity hyperreflexia, evidence of a superimposed myelopathy. A nerve biopsy showed evidence of chronic axonal loss. All affected family members had a heterozygous missense mutation c.304G>C (p.Gly102Arg) in the alanyl-tRNA synthetase (AARS) gene; this allele was not identified in unaffected individuals or control samples. The equivalent change in the yeast ortholog failed to complement a strain of yeast lacking AARS function, suggesting that the mutation is damaging. A novel mutation in AARS causes a mild myeloneuropathy, a novel phenotype for patients with mutations in one of the tRNA synthetase genes. © 2015 American Academy of Neurology.

ACUDIN - ACUpuncture and laser acupuncture for treatment of DIabetic peripheral Neuropathy: a randomized, placebo-controlled, partially double-blinded trial.

PubMed

Meyer-Hamme, Gesa; Friedemann, Thomas; Greten, Henry Johannes; Plaetke, Rosemarie; Gerloff, Christian; Schroeder, Sven

2018-04-13

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus with significant clinical sequelae that can affect a patient's quality of life. Metabolic and microvascular factors are responsible for nerve damage, causing loss of nerve function, numbness, painful sensory symptoms, and muscle weakness. Therapy is limited to anti-convulsant or anti-depressant drugs for neuropathic pain and paresthesia. However, reduced sensation, balance and gait problems are insufficiently covered by this treatment. Previous data suggests that acupuncture, which has been in use in Traditional Chinese Medicine for many years, may potentially complement the treatment options for peripheral neuropathy. Nevertheless, more objective data on clinical outcome is necessary to generally recommend acupuncture to the public. We developed a study design for a prospective, randomized (RCT), placebo-controlled, partially double-blinded trial for investigating the effect of acupuncture on DPN as determined by nerve conduction studies (NCS) with the sural sensory nerve action potential amplitude as the primary outcome. The sural sensory nerve conduction velocity, tibial motor nerve action potential amplitude, tibial motor nerve conduction velocity, the neuropathy deficit score, neuropathy symptom score, and numeric rating scale questionnaires are defined as secondary outcomes. One hundred and eighty patients with type 2 diabetes mellitus will be randomized into three groups (needle acupuncture, verum laser acupuncture, and placebo laser acupuncture). We hypothesize that needle and laser acupuncture have beneficial effects on electrophysiological parameters and clinical and subjective symptoms in relation to DPN in comparison with placebo. The ACUDIN trial aims at investigating whether classical needle acupuncture and/or laser acupuncture are efficacious in the treatment of DPN. For the purpose of an objective parameter, NCS were chosen as outcome measures. Acupuncture treatment may potentially improve patients' quality of life and reduce the socio-economic burden caused by DPN. German Clinical Trial Register (DRKS), No. DRKS00008562 , trial search portal of the WHO ( http://apps.who.int/trialsearch/ ).

Gasserian Ganglion and Retrobulbar Nerve Block in the Treatment of Ophthalmic Postherpetic Neuralgia: A Case Report.

PubMed

Huang, Jie; Ni, Zhongge; Finch, Philip

2017-09-01

Varicella zoster virus reactivation can cause permanent histological changes in the central and peripheral nervous system. Neural inflammatory changes or damage to the dorsal root ganglia sensory nerve fibers during reactivation can lead to postherpetic neuralgia (PHN). For PHN of the first division of the fifth cranial nerve (ophthalmic division of the trigeminal ganglion), there is evidence of inflammatory change in the ganglion and adjacent ocular neural structures. First division trigeminal nerve PHN can prove to be difficult and sometimes even impossible to manage despite the use of a wide range of conservative measures, including anticonvulsant and antidepressant medication. Steroids have been shown to play an important role by suppressing neural inflammatory processes. We therefore chose the trigeminal ganglion as an interventional target for an 88-year-old woman with severe ophthalmic division PHN after she failed to respond to conservative treatment. Under fluoroscopic guidance, a trigeminal ganglion nerve block was performed with lidocaine combined with dexamethasone. A retrobulbar block with lidocaine and triamcinolone settled residual oculodynia. At 1-year follow-up, the patient remained pain free and did not require analgesic medication. To our knowledge, this is the first reported case of ophthalmic division PHN successfully treated with a combination of trigeminal ganglion and retrobulbar nerve block using a local anesthetic agent and steroid for central and peripheral neural inflammatory processes. © 2016 World Institute of Pain.

Altered ion channel conductance and ionic selectivity induced by large imposed membrane potential pulse.

PubMed Central

Chen, W; Lee, R C

1994-01-01

The effects of large magnitude transmembrane potential pulses on voltage-gated Na and K channel behavior in frog skeletal muscle membrane were studied using a modified double vaseline-gap voltage clamp. The effects of electroconformational damage to ionic channels were separated from damage to lipid bilayer (electroporation). A 4 ms transmembrane potential pulse of -600 mV resulted in a reduction of both Na and K channel conductivities. The supraphysiologic pulses also reduced ionic selectivity of the K channels against Na+ ions, resulting in a depolarization of the membrane resting potential. However, TTX and TEA binding effects were unaltered. The kinetics of spontaneous reversal of the electroconformational damage of channel proteins was found to be dependent on the magnitude of imposed membrane potential pulse. These results suggest that muscle and nerve dysfunction after electrical shock may be in part caused by electroconformational damage to voltage-gated ion channels. PMID:7948676

High Spatial Resolution Imaging Mass Spectrometry of Human Optic Nerve Lipids and Proteins

NASA Astrophysics Data System (ADS)

Anderson, David M. G.; Spraggins, Jeffrey M.; Rose, Kristie L.; Schey, Kevin L.

2015-06-01

The human optic nerve carries signals from the retina to the visual cortex of the brain. Each optic nerve is comprised of approximately one million nerve fibers that are organized into bundles of 800-1200 fibers surrounded by connective tissue and supportive glial cells. Damage to the optic nerve contributes to a number of blinding diseases including: glaucoma, neuromyelitis optica, optic neuritis, and neurofibromatosis; however, the molecular mechanisms of optic nerve damage and death are incompletely understood. Herein we present high spatial resolution MALDI imaging mass spectrometry (IMS) analysis of lipids and proteins to define the molecular anatomy of the human optic nerve. The localization of a number of lipids was observed in discrete anatomical regions corresponding to myelinated and unmyelinated nerve regions as well as to supporting connective tissue, glial cells, and blood vessels. A protein fragment from vimentin, a known intermediate filament marker for astrocytes, was observed surrounding nerved fiber bundles in the lamina cribrosa region. S100B was also found in supporting glial cell regions in the prelaminar region, and the hemoglobin alpha subunit was observed in blood vessel areas. The molecular anatomy of the optic nerve defined by MALDI IMS provides a firm foundation to study biochemical changes in blinding human diseases.

Evaluation of tissue components in the peripheral nervous system using Sirius red staining and immunohistochemistry: a comparative study (human, pig, rat).

PubMed

Kaemmer, D; Bozkurt, A; Otto, J; Junge, K; Klink, C; Weis, J; Sellhaus, B; O'Dey, D M; Pallua, N; Jansen, M; Schumpelick, V; Klinge, U

2010-06-30

Little is known about species differences in the peripheral nerve system and quantitative evaluation of main tissue components has rarely been done. Nevertheless, animal models are used for example in pain research without exact knowledge of degree of fibrosis in pathological states which would determine possible treatment options. It would therefore be of crucial interest to describe the degree of fibrosis and the remaining functional nerve tissue as exact as possible. In the present study we evaluated collagen (stroma) and nerve fiber (parenchyma) composition of peripheral nerves in three species (human, rat, pig) and used digital colour-separation and analysis for collagen type differentiation and quantification of immuno-positive-stained area. We found similar ratios of collagen types I and III in epineurium and similar immuno-positive area for staining of neurofilament and S-100beta. In contrast, we measured significantly different ratios of collagen type I to type III in the endoneurium. This combined analysis of the main tissue components of peripheral nerves could be an easy-to-use tool in evaluating changes during damage caused by scaring, systemic disease or compression syndromes. The calculated collagen type I/III ratio may serve as an objective diagnostic value for the description or as prognostic marker for therapeutic approaches in peripheral nerve pathology. However, in particular studies of collagen accumulation in nerves, species dependant differences have to be considered. Copyright 2010 Elsevier B.V. All rights reserved.

Longitudinal evidence for anterograde trans-synaptic degeneration after optic neuritis

PubMed Central

Goodkin, Olivia; Altmann, Daniel R.; Jenkins, Thomas M.; Miszkiel, Katherine; Mirigliani, Alessia; Fini, Camilla; Gandini Wheeler-Kingshott, Claudia A. M.; Thompson, Alan J.; Ciccarelli, Olga; Toosy, Ahmed T.

2016-01-01

Abstract In multiple sclerosis, microstructural damage of normal-appearing brain tissue is an important feature of its pathology. Understanding these mechanisms is vital to help develop neuroprotective strategies. The visual pathway is a key model to study mechanisms of damage and recovery in demyelination. Anterograde trans-synaptic degeneration across the lateral geniculate nuclei has been suggested as a mechanism of tissue damage to explain optic radiation abnormalities seen in association with demyelinating disease and optic neuritis, although evidence for this has relied solely on cross-sectional studies. We therefore aimed to assess: (i) longitudinal changes in the diffusion properties of optic radiations after optic neuritis suggesting trans-synaptic degeneration; (ii) the predictive value of early optic nerve magnetic resonance imaging measures for late optic radiations changes; and (iii) the impact on visual outcome of both optic nerve and brain post-optic neuritis changes. Twenty-eight consecutive patients with acute optic neuritis and eight healthy controls were assessed visually (logMAR, colour vision, and Sloan 1.25%, 5%, 25%) and by magnetic resonance imaging, at baseline, 3, 6, and 12 months. Magnetic resonance imaging sequences performed (and metrics obtained) were: (i) optic nerve fluid-attenuated inversion-recovery (optic nerve cross-sectional area); (ii) optic nerve proton density fast spin-echo (optic nerve proton density-lesion length); (iii) optic nerve post-gadolinium T 1 -weighted (Gd-enhanced lesion length); and (iv) brain diffusion-weighted imaging (to derive optic radiation fractional anisotropy, radial diffusivity, and axial diffusivity). Mixed-effects and multivariate regression models were performed, adjusting for age, gender, and optic radiation lesion load. These identified changes over time and associations between early optic nerve measures and 1-year global optic radiation/clinical measures. The fractional anisotropy in patients’ optic radiations decreased ( P = 0.018) and radial diffusivity increased ( P = 0.002) over 1 year following optic neuritis, whereas optic radiation measures were unchanged in controls. Also, smaller cross-sectional areas of affected optic nerves at 3 months post-optic neuritis predicted lower fractional anisotropy and higher radial diffusivity at 1 year ( P = 0.007) in the optic radiations, whereas none of the inflammatory measures of the optic nerve predicted changes in optic radiations. Finally, greater Gd-enhanced lesion length at baseline and greater optic nerve proton density-lesion length at 1 year were associated with worse visual function at 1 year ( P = 0.034 for both). Neither the cross-sectional area of the affected optic nerve after optic neuritis nor the damage in optic radiations was associated with 1-year visual outcome. Our longitudinal study shows that, after optic neuritis, there is progressive damage to the optic radiations, greater in patients with early residual optic nerve atrophy, even after adjusting for optic radiation lesions. These findings provide evidence for trans-synaptic degeneration. PMID:26912640

Mechanisms of, and Adjuvants for, Bone Pain.

PubMed

Figura, Nicholas; Smith, Joshua; Yu, Hsiang-Hsuan Michael

2018-06-01

Metastatic bone pain is a complex, poorly understood process. Understanding the unique mechanisms causing cancer-induced bone pain may lead to potential therapeutic targets. This article discusses the effects of osteoclast overstimulation within the tumor microenvironment; the role of inflammatory factors at the tumor-nociceptor interface; the development of structural instability, causing mechanical nerve damage; and, ultimately, the neuroplastic changes in the setting of sustained pain. Several adjuvant therapies are available to attenuate metastatic bone pain. This article discusses the role of pharmacologic therapies, surgery, kyphoplasty, vertebroplasty, and radiofrequency ablation. Copyright © 2018 Elsevier Inc. All rights reserved.

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

PubMed

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.

Vision Integrating Strategies in Ophthalmology and Neurochemistry (VISION)

DTIC Science & Technology

2016-08-01

ocular hypertension ). We have developed techniques to quantify damage to the retina, optic nerve, and visual axis in the brain (i.e. superior...injury with different injury-initiating mechanisms (i.e. optic nerve crush, retinal ischemia/reperfusion, and chronic ocular hypertension ). We...protected retinal ganglion cells from ocular hypertension induced damage and appeared to stimulate axonal regeneration. Sigma-1 receptor agonists and

The vestibulocochlear nerve (VIII).

PubMed

Benoudiba, F; Toulgoat, F; Sarrazin, J-L

2013-10-01

The vestibulocochlear nerve (8th cranial nerve) is a sensory nerve. It is made up of two nerves, the cochlear, which transmits sound and the vestibular which controls balance. It is an intracranial nerve which runs from the sensory receptors in the internal ear to the brain stem nuclei and finally to the auditory areas: the post-central gyrus and superior temporal auditory cortex. The most common lesions responsible for damage to VIII are vestibular Schwannomas. This report reviews the anatomy and various investigations of the nerve. Copyright © 2013. Published by Elsevier Masson SAS.

Management of asymptomatic gene carriers of transthyretin familial amyloid polyneuropathy.

PubMed

Schmidt, Hartmut H-J; Barroso, Fabio; González-Duarte, Alejandra; Conceição, Isabel; Obici, Laura; Keohane, Denis; Amass, Leslie

2016-09-01

Transthyretin familial amyloid polyneuropathy (TTR-FAP) is a rare, severe, and irreversible, adult-onset, hereditary disorder caused by autosomal-dominant mutations in the TTR gene that increase the intrinsic propensity of transthyretin protein to misfold and deposit systemically as insoluble amyloid fibrils in nerve tissues, the heart, and other organs. TTR-FAP is characterized by relentless, progressively debilitating polyneuropathy, and leads to death, on average, within 10 years of symptom onset without treatment. With increased availability of disease-modifying treatment options for a wider spectrum of patients with TTR-FAP, timely detection of the disease may offer substantial clinical benefits. This review discusses mutation-specific predictive genetic testing in first-degree relatives of index patients diagnosed with TTR-FAP and the structured clinical follow-up of asymptomatic gene carriers for prompt diagnosis and early therapeutic intervention before accumulation of substantial damage. Muscle Nerve 54: 353-360, 2016. © 2016 The Authors Muscle & Nerve Published by Wiley Periodicals, Inc.

Corneal Confocal Microscopy Detects Corneal Nerve Damage in Patients Admitted With Acute Ischemic Stroke.

PubMed

Khan, Adnan; Akhtar, Naveed; Kamran, Saadat; Ponirakis, Georgios; Petropoulos, Ioannis N; Tunio, Nahel A; Dargham, Soha R; Imam, Yahia; Sartaj, Faheem; Parray, Aijaz; Bourke, Paula; Khan, Rabia; Santos, Mark; Joseph, Sujatha; Shuaib, Ashfaq; Malik, Rayaz A

2017-11-01

Corneal confocal microscopy can identify corneal nerve damage in patients with peripheral and central neurodegeneration. However, the use of corneal confocal microscopy in patients presenting with acute ischemic stroke is unknown. One hundred thirty patients (57 without diabetes mellitus [normal glucose tolerance], 32 with impaired glucose tolerance, and 41 with type 2 diabetes mellitus) admitted with acute ischemic stroke, and 28 age-matched healthy control participants underwent corneal confocal microscopy to quantify corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length. There was a significant reduction in corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length in stroke patients with normal glucose tolerance ( P <0.001, P <0.001, P <0.001), impaired glucose tolerance ( P =0.004, P <0.001, P =0.002), and type 2 diabetes mellitus ( P <0.001, P <0.001, P <0.001) compared with controls. HbA1c and triglycerides correlated with corneal nerve fiber density ( r =-0.187, P =0.03; r =-0.229 P =0.01), corneal nerve fiber length ( r =-0.228, P =0.009; r =-0.285; P =0.001), and corneal nerve branch density ( r =-0.187, P =0.033; r =-0.229, P =0.01). Multiple linear regression showed no independent associations between corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length and relevant risk factors for stroke. Corneal confocal microscopy is a rapid noninvasive ophthalmic imaging technique that identifies corneal nerve fiber loss in patients with acute ischemic stroke. © 2017 American Heart Association, Inc.

Progressive Muscle Atrophy and Weakness After Treatment by Mantle Field Radiotherapy in Hodgkin Lymphoma Survivors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leeuwen-Segarceanu, Elena M. van, E-mail: e.segarceanu@antoniusziekenhuis.nl; Dorresteijn, Lucille D.A.; Pillen, Sigrid

Purpose: To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. Methods and Materials: We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Results: Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. Onmore » ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Conclusions: Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles.« less

Acquired pit of the optic nerve: a risk factor for progression of glaucoma.

PubMed

Ugurlu, S; Weitzman, M; Nduaguba, C; Caprioli, J

1998-04-01

To examine acquired pit of the optic nerve as a risk factor for progression of glaucoma. In a retrospective longitudinal study, 25 open-angle glaucoma patients with acquired pit of the optic nerve were compared with a group of 24 open-angle glaucoma patients without acquired pit of the optic nerve. The patients were matched for age, mean intraocular pressure, baseline ratio of neuroretinal rim area to disk area, visual field damage, and duration of follow-up. Serial optic disk photographs and visual fields of both groups were evaluated by three independent observers for glaucomatous progression. Of 46 acquired pits of the optic nerve in 37 eyes of 25 patients, 36 pits were located inferiorly (76%) and 11 superiorly (24%; P < .001). Progression of optic disk damage occurred in 16 patients (64%) in the group with acquired pit and in three patients (12.5%) in the group without acquired pit (P < .001). Progression of visual field loss occurred in 14 patients (56%) in the group with acquired pit and in six (25%) in the group without pit (P=.04). Bilateral acquired pit of the optic nerve was present in 12 patients (48%). Disk hemorrhages were observed more frequently in the group with acquired pit (10 eyes, 40%) compared with the group without pit (two eyes, 8%; P=.02). Among patients with glaucoma, patients with acquired pit of the optic nerve represent a subgroup who are at increased risk for progressive optic disk damage and visual field loss.

Microstructural and ultrastructural assessment of inferior alveolar nerve damage following nerve lateralization and implant placement: an experimental study in rabbits.

PubMed

Yoshimoto, Marcelo; Watanabe, Il-sei; Martins, Marília T; Salles, Marcos B; Ten Eyck, Gary R; Coelho, Paulo G

2009-01-01

The present study assessed damage to the inferior alveolar nerve (IAN) following nerve lateralization and implant placement surgery through optical and transmission electron microscopy (TEM). IAN lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, one implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant. The implant was placed in the right mandible, and the left side was used as a control (no surgical procedure). After 8 weeks, the animals were sacrificed and samples were prepared for optical and TEM analysis of IAN structural damage. Histomorphometric analysis was performed to determine the number and cross-sectional dimensions of nerve fascicles and myelin sheath thickness between experimental and control groups. The different parameters were compared by one-way analysis of variance at the 95% significance level. Alterations in the perineural and endoneural regions of the IAN, with higher degrees of vascularization, were observed in the experimental group. TEM showed that the majority of the myelinated nerve fibers were not affected in the experimental samples. No significant variation in the number of fascicles was observed, significantly larger fascicle height and width were observed in the control group, and significantly thicker myelin sheaths were observed in the experimental samples. IAN lateralization resulted in substantial degrees of tissue disorganization at the microstructural level because of the presence of edema. However, at the ultrastructural level, small amounts of fiber degeneration were observed.

Patterns of intraocular pressure elevation after aqueous humor outflow obstruction in rats.

PubMed

Jia, L; Cepurna, W O; Johnson, E C; Morrison, J C

2000-05-01

To determine the diural intraocular pressure (IOP) response of Brown Norway rat eyes after sclerosis of the aqueous humor outflow pathways and its relationship to optic nerve damage. Hypertonic saline was injected into a single episcleral vein in 17 animals and awake IOP measured in both the light and dark phases of the circadian cycle for 34 days. Mean IOP for light and dark phases during the experimental period were compared with the respective pressures of the uninjected fellow eyes. Optic nerve cross sections from each nerve were graded for injury by five independent masked observers. For fellow eyes, mean light- and dark-phase IOP was 21 +/- 1 and 31 +/- 1 mm Hg, respectively. For four experimental eyes, mean IOPs for both phases were not altered. Six eyes demonstrated significant mean IOP elevations only during the dark phase. Of these, five showed persistent, large circadian oscillations, and four had partial optic nerve lesions. The remaining seven eyes experienced significant IOP elevations during both phases, and all had extensive optic nerve damage. Episcleral vein injection of hypertonic saline is more likely to increase IOP during the dark phase than the light. This is consistent with aqueous outflow obstruction superimposed on a circadian rhythm of aqueous humor production. Because these periodic IOP elevations produced optic nerve lesions, both light- and dark-phase IOP determinations are necessary for accurate correlation of IOP history to optic nerve damage in animals housed in a light- dark environment.

Neuro-ophthalmological approach to facial nerve palsy

PubMed Central

Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

2014-01-01

Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell’s palsy, Ramsay–Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell’s palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell’s palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell’s phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell’s palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration with synkinesis. FNP after acoustic neuroma surgery remains the most common indication for FN rehabilitation. PMID:25859138

Pressure wave injuries to rat dorsal root ganglion cells in culture caused by high-energy missiles.

PubMed

Suneson, A; Hansson, H A; Lycke, E; Seeman, T

1989-01-01

A high-energy missile impact in an extremity of an animal creates a shock wave which is rapidly dispersed as a burst of oscillating pressure waves that traverses the entire body causing local, regional, and distant injuries. The present study was performed on dorsal root ganglion (DRG) cells, cultured for 3 weeks, to elucidate the cellular mechanism for damage of nerve cells, using a simplified test system. A model system was developed allowing exposure of DRG cultures to a burst of high-frequency oscillating pressure waves, comparable to those recorded in animals after high-energy missile extremity impact. The pressure waves were induced by impact of a high-energy missile in a rubber tube filled with water, in which nerve cell cultures were kept in a closed rubber glove filled with tissue culture medium. The pressure waves had a duration of 0.5-1.5 ms and a frequency spectrum ranging from 0-250 kHz. Within minutes the neurites showed changes in their microtubules. In addition, varicosities, enriched with tubulin immunoreactive material, became irregularly studded along the nerve cell processes. Scattered DRG cells were initially permeable to the marker complex Evans-blue albumin (EBA), used as an indicator of the ability of the plasma membranes to exclude proteins. After 6 hr, however, almost every DRG neuron was intensely stained by EBA. Concomitantly, there was swelling of the nerve cell cytoplasm and organelles, and, to a variable extent, neurofilament tangles were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Neural autoantibodies and neurophysiologic abnormalities in patients exposed to molds in water-damaged buildings.

PubMed

Campbell, Andrew W; Thrasher, Jack D; Madison, Roberta A; Vojdani, Aristo; Gray, Michael R; Johnson, Al

2003-08-01

Adverse health effects of fungal bioaerosols on occupants of water-damaged homes and other buildings have been reported. Recently, it has been suggested that mold exposure causes neurological injury. The authors investigated neurological antibodies and neurophysiological abnormalities in patients exposed to molds at home who developed symptoms of peripheral neuropathy (i.e., numbness, tingling, tremors, and muscle weakness in the extremities). Serum samples were collected and analyzed with the enzyme-linked immunosorbent assay (ELISA) technique for antibodies to myelin basic protein, myelin-associated glycoprotein, ganglioside GM1, sulfatide, myelin oligodendrocyte glycoprotein, alpha-B-crystallin, chondroitin sulfate, tubulin, and neurofilament. Antibodies to molds and mycotoxins were also determined with ELISA, as reported previously. Neurophysiologic evaluations for latency, amplitude, and velocity were performed on 4 motor nerves (median, ulnar, peroneal, and tibial), and for latency and amplitude on 3 sensory nerves (median, ulnar, and sural). Patients with documented, measured exposure to molds had elevated titers of antibodies (immunoglobulin [Ig]A, IgM, and IgG) to neural-specific antigens. Nerve conduction studies revealed 4 patient groupings: (1) mixed sensory-motor polyneuropathy (n = 55, abnormal), (2) motor neuropathy (n = 17, abnormal), (3) sensory neuropathy (n = 27, abnormal), and (4) those with symptoms but no neurophysiological abnormalities (n = 20, normal controls). All groups showed significantly increased autoantibody titers for all isotypes (IgA, IgM, and IgG) of antibodies to neural antigens when compared with 500 healthy controls. Groups 1 through 3 also exhibited abnormal neurophysiologic findings. The authors concluded that exposure to molds in water-damaged buildings increased the risk for development of neural autoantibodies, peripheral neuropathy, and neurophysiologic abnormalities in exposed individuals.

Hydrostatic Pressure–Induced Release of Stored Calcium in Cultured Rat Optic Nerve Head Astrocytes

PubMed Central

Mandal, Amritlal; Delamere, Nicholas A.

2010-01-01

Purpose. Elevated intraocular pressure is associated with glaucomatous optic nerve damage. Other investigators have shown functional changes in optic nerve head astrocytes subjected to elevated hydrostatic pressure (HP) for 1 to 5 days. Recently, the authors reported ERK1/2, p90RSK and NHE1 phosphorylation after 2 hours. Here they examine calcium responses at the onset of HP to determine what precedes ERK1/2 phosphorylation. Methods. Cytoplasmic calcium concentration ([Ca2+]i) was measured in cultured rat optic nerve astrocytes loaded with fura-2. The cells were placed in a closed imaging chamber and subjected to an HP increase of 15 mm Hg. Protein phosphorylation was detected by Western blot analysis. Results. The increase of HP caused an immediate slow increase in [Ca2+]i. The response persisted in calcium-free solution and when nickel chloride (4 mM) was added to suppress channel-mediated calcium entry. Previous depletion of the ER calcium stores by cyclopiazonic acid abolished the HP-induced calcium level increase. The HP-induced increase persisted in cells exposed to xestospongin C, an inhibitor of IP3R-mediated calcium release. In contrast, ryanodine receptor (RyR) antagonist ruthenium red (10 μM) or dantrolene (25 μM) inhibited the HP-induced calcium increase. The HP-induced calcium increase was abolished when ryanodine-sensitive calcium stores were pre-depleted with caffeine (3 mM). HP caused ERK1/2 phosphorylation. The magnitude of the ERK1/2 phosphorylation response was reduced by ruthenium red and dantrolene. Conclusions. Increasing HP causes calcium release from a ryanodine-sensitive cytoplasmic store and subsequent ERK1/2 activation. Calcium store release appears to be a required early step in the initial astrocyte response to an HP increase. PMID:20071675

Effects of local application of methylprednisolone delivered by the C/GP-hydrogel on the recovery of facial nerves.

PubMed

Chao, Xiuhua; Fan, Zhaomin; Han, Yuechen; Wang, Yan; Li, Jianfeng; Chai, Renjie; Xu, Lei; Wang, Haibo

2015-01-01

Local administration of MP delivered by the C/GP-MP-hydrogel can improve the recovery of facial nerve following crush injury. The findings suggested that locally injected MP delivered by C/GP-hydrogel might be a promising treatment for facial nerve damage. In this study, the aim is to assess the effectiveness of locally administrating methylprednisolone(MP) loaded by chitosan-β-glycerophosphate hydrogel (C/GP-hydrogel) on the regeneration of facial nerve crush injury. After the crush of left facial nerves, Wistar rats were randomly divided into four different groups. Then, four different therapies were used to treat the damaged facial nerves. At the 1(st), 2(nd), 3(rd), and 4(th) week after injury, the functional recovery of facial nerves and the morphological changes of facial nerves were assessed. The expression of growth associated protein-43 (GAP-43) protein in the facial nucleus were also evaluated. Locally injected MP delivered by C/GP-hydrogel effectively accelerated the facial functional recovery. In addition, the regenerated facial nerves in the C/GP-MP group were more mature than those in the other groups. The expression of GAP-43 protein was also improved by the MP, especially in the C/GP-MP group.

Hierarchical structural health monitoring system combining a fiber optic spinal cord network and distributed nerve cell devices

NASA Astrophysics Data System (ADS)

Minakuchi, Shu; Tsukamoto, Haruka; Takeda, Nobuo

2009-03-01

This study proposes novel hierarchical sensing concept for detecting damages in composite structures. In the hierarchical system, numerous three-dimensionally structured sensor devices are distributed throughout the whole structural area and connected with the optical fiber network through transducing mechanisms. The distributed "sensory nerve cell" devices detect the damage, and the fiber optic "spinal cord" network gathers damage signals and transmits the information to a measuring instrument. This study began by discussing the basic concept of the hierarchical sensing system thorough comparison with existing fiber optic based systems and nerve systems in the animal kingdom. Then, in order to validate the proposed sensing concept, impact damage detection system for the composite structure was proposed. The sensor devices were developed based on Comparative Vacuum Monitoring (CVM) system and the Brillouin based distributed strain sensing was utilized to gather the damage signals from the distributed devices. Finally a verification test was conducted using prototype devices. Occurrence of barely visible impact damage was successfully detected and it was clearly indicated that the hierarchical system has better repairability, higher robustness, and wider monitorable area compared to existing systems utilizing embedded optical fiber sensors.

Brachial Plexus Injury in a 6-Year-Old Boy with 100% Displaced Proximal Humeral Metaphyseal Fracture: A Case Presentation.

PubMed

Jovanovich, Elizabeth Nora; Howard, James F

2017-12-01

Posttraumatic brachial plexopathies can occur following displaced proximal humeral fractures, causing profound functional deficits. Described here is an unusual case of a displaced proximal humeral metaphyseal fracture in a young child. The patient underwent closed reduction and serial casting, but hand weakness and forearm sensory loss persisted. Needle electromyography localized the injury to the mid/proximal arm near the fracture site, resulting in damage to the posterior and medial cords of the brachial plexus with profound involvement of the radial, ulnar, and median nerves and sparing of the axillary nerve. After months of occupational therapy, hand strength improved, with a nearly full return of function. V. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Glaucoma drops control intraocular pressure and protect optic nerves in a rat model of glaucoma.

PubMed

Morrison, J C; Nylander, K B; Lauer, A K; Cepurna, W O; Johnson, E

1998-03-01

To determine whether chronic topical glaucoma therapy can control intraocular pressure (IOP) and protect nerve fibers in a rat model of pressure-induced optic nerve damage. Sixteen adult Brown Norway rats were-administered unilateral episcleral vein injections of hypertonic saline to produce scarring of the aqueous humor outflow pathways. Twice daily applications of either artificial tears (n = 6), 0.5% betaxolol (n = 5), or 0.5% apraclonidine (n = 5) were delivered to both eyes, and awake pressures were monitored with a TonoPen XL tonometer for 17 days before the rats were killed. For animals administered artificial tears, the mean IOP of the experimental eyes was 39 +/- 2 mm Hg compared with 29 +/- 1 mm Hg for the control eyes. This difference was statistically significant (P < 0.001). Mean IOPs in the experimental eyes of animals administered betaxolol and apraclonidine were 29 +/- 7 and 29 +/- 4 mm Hg, respectively, whereas the mean IOP in the control eyes was 28 +/- 1 mm Hg for both groups. There was no statistically significant difference among these values. The mean IOP for the experimental eyes in the betaxolol and apraclonidine groups was lower than that in animals administered artificial tears (P = 0.003). Quantitative histologic analysis of optic nerve damage in experimental eyes showed that four of the six animals administered artificial tears had damage involving 100% of the neural area. This degree of damage appeared in only 3 of 10 animals administered glaucoma therapy. Optic nerve protection was closely correlated with IOP history because damage was limited to less than 10% of the cross-sectional area in all animals in which the maximal IOP was less than or equal to 39 mm Hg, more than 2 SD below the mean value for eyes administered artificial tears. Topical glaucoma therapy in this model can prevent IOP elevation and protect optic nerve fibers.

Hypertension in kidney transplantation is associated with an early renal nerve sprouting

PubMed Central

Rovella, Valentina; Borri, Filippo; Anemona, Lucia; Giannini, Elena; Giacobbi, Erica; Saggini, Andrea; Palmieri, Giampiero; Anselmo, Alessandro; Bove, Pierluigi; Melino, Gerry; Valentina, Guardini; Tesauro, Manfredi; Gabriele, D’Urso; Di Daniele, Nicola

2017-01-01

Abstract Background. Normalization of arterial pressure occurs in just a few patients with hypertensive chronic kidney disease undergoing kidney transplantation. Hypertension in kidney transplant recipients may be related to multiple factors. We aimed to assess whether hypertension in kidney-transplanted patients may be linked to reinnervation of renal arteries of the transplanted kidney. Methods. We investigated renal arteries innervation from native and transplanted kidneys in three patients 5 months, 2 years and 11 years after transplantation, respectively. Four transplanted kidneys from non-hypertensive patients on immunosuppressive treatment without evidence of hypertensive arteriolar damage were used as controls. Results. Evidence of nerve sprouting was observed as early as 5 months following transplantation, probably originated from ganglions of recipient patient located near the arterial anastomosis and was associated with mild hypertensive arteriolar damage. Regeneration of periadventitial nerves was already complete 2 years after transplantation. Nerve density tended to reach values observed in native kidney arteries and was associated with hypertension-related arteriolar lesions in transplanted kidneys. Control kidneys, albeit on an immunosuppressive regimen, presented only a modest regeneration of sympathetic nerves. Conclusions. Our results suggest that the considerable increase in sympathetic nerves, as found in patients with severe arterial damage, may be correlated to hypertension rather than to immunosuppressive therapy, thus providing a morphological basis for hypertension recurrence despite renal denervation. PMID:28498963

POEMS Syndrome Diagnosed 10 Years after Disabling Peripheral Neuropathy.

PubMed

Nguyen, Viet H

2011-01-01

Peripheral neuropathy is characterized as a generalized, relatively homogeneous process affecting many peripheral nerves and predominantly affecting distal nerves. The epidemiology of peripheral neuropathy is limited since the disease presents with varying etiology, pathology, and severity. Toxic, inflammatory, hereditary, and infectious factors can cause damage to the peripheral nerves resulting in peripheral neuropathy. Peripheral neuropathy is most commonly caused by diabetes, alcohol, HIV infection, and malignancy. We report a case of a 42-year-old female with 10-year history of progressively worsening peripheral neuropathy, hypothyroidism, and skin changes who presents with dyspnea secondary to recurrent pleural and pericardial effusions. Prior to her arrival, her peripheral neuropathy was believed to be secondary to chronic demyelinating inflammatory polyneuropathy (CDIP) given elevated protein in the cerebral spinal fluid (CSF) which was treated with intravenous immunoglobulin (IVIG) and corticosteroids. Unfortunately, her peripheral neuropathy did not have any improvement. Incidentally, patient was found to have splenomegaly and papilledema on physical exam. Serum protein electrophoresis showed a monoclonal pattern of IgA lambda. Patient met the diagnostic criteria for POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes) syndrome. An underlying diagnosis of POEMS syndrome should be considered in patients with chronic debilitating neuropathy and an elevated protein in the CSF.

POEMS Syndrome Diagnosed 10 Years after Disabling Peripheral Neuropathy

PubMed Central

Nguyen, Viet H.

2011-01-01

Peripheral neuropathy is characterized as a generalized, relatively homogeneous process affecting many peripheral nerves and predominantly affecting distal nerves. The epidemiology of peripheral neuropathy is limited since the disease presents with varying etiology, pathology, and severity. Toxic, inflammatory, hereditary, and infectious factors can cause damage to the peripheral nerves resulting in peripheral neuropathy. Peripheral neuropathy is most commonly caused by diabetes, alcohol, HIV infection, and malignancy. We report a case of a 42-year-old female with 10-year history of progressively worsening peripheral neuropathy, hypothyroidism, and skin changes who presents with dyspnea secondary to recurrent pleural and pericardial effusions. Prior to her arrival, her peripheral neuropathy was believed to be secondary to chronic demyelinating inflammatory polyneuropathy (CDIP) given elevated protein in the cerebral spinal fluid (CSF) which was treated with intravenous immunoglobulin (IVIG) and corticosteroids. Unfortunately, her peripheral neuropathy did not have any improvement. Incidentally, patient was found to have splenomegaly and papilledema on physical exam. Serum protein electrophoresis showed a monoclonal pattern of IgA lambda. Patient met the diagnostic criteria for POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes) syndrome. An underlying diagnosis of POEMS syndrome should be considered in patients with chronic debilitating neuropathy and an elevated protein in the CSF. PMID:22013451

A Closer Look at Schlemm's Canal Cell Physiology: Implications for Biomimetics.

PubMed

Dautriche, Cula N; Tian, Yangzi; Xie, Yubing; Sharfstein, Susan T

2015-09-21

Among ocular pathologies, glaucoma is the second leading cause of progressive vision loss, expected to affect 80 million people worldwide by 2020. A primary cause of glaucoma appears to be damage to the conventional outflow tract. Conventional outflow tissues, a composite of the trabecular meshwork and the Schlemm's canal, regulate and maintain homeostatic responses to intraocular pressure. In glaucoma, filtration of aqueous humor into the Schlemm's canal is hindered, leading to an increase in intraocular pressure and subsequent damage to the optic nerve, with progressive vision loss. The Schlemm's canal encompasses a unique endothelium. Recent advances in culturing and manipulating Schlemm's canal cells have elucidated several aspects of their physiology, including ultrastructure, cell-specific marker expression, and biomechanical properties. This review highlights these advances and discusses implications for engineering a 3D, biomimetic, in vitro model of the Schlemm's canal endothelium to further advance glaucoma research, including drug testing and gene therapy screening.

Gulf War illnesses are autoimmune illnesses caused by reactive oxygen species which were caused by nerve agent prophylaxis.

PubMed

Moss, J I

2012-08-01

Gulf War illnesses (GWI share many of the features of chronic fatigue syndrome (CFS) and both CFS and GWI may be the result of chronic immune system processes. The main suspected cause for GWI, the drug pyridostigmine bromide (PB), has been shown to cause neuronal damage from reactive oxygen species (ROS). ROS have been associated with IgM mediated autoimmune responses against ROS induced neoepitopes in depressed patients and this may also apply to CFS. It therefore follows that the drug used in the Gulf War caused ROS, the ROS modified native molecules, and that this trigged the autoimmune condition we refer to as Gulf War illnesses. Similar mechanisms may apply to other autoimmune illnesses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mephedrone does not damage dopamine nerve endings of the striatum, but enhances the neurotoxicity of methamphetamine, amphetamine, and MDMA.

PubMed

Angoa-Pérez, Mariana; Kane, Michael J; Briggs, Denise I; Francescutti, Dina M; Sykes, Catherine E; Shah, Mrudang M; Thomas, David M; Kuhn, Donald M

2013-04-01

Mephedrone (4-methylmethcathinone) is a β-ketoamphetamine stimulant drug of abuse with close structural and mechanistic similarities to methamphetamine. One of the most powerful actions associated with mephedrone is the ability to stimulate dopamine (DA) release and block its re-uptake through its interaction with the dopamine transporter (DAT). Although mephedrone does not cause toxicity to DA nerve endings, its ability to serve as a DAT blocker could provide protection against methamphetamine-induced neurotoxicity like other DAT inhibitors. To test this possibility, mice were treated with mephedrone (10, 20, or 40 mg/kg) prior to each injection of a neurotoxic regimen of methamphetamine (four injections of 2.5 or 5.0 mg/kg at 2 h intervals). The integrity of DA nerve endings of the striatum was assessed through measures of DA, DAT, and tyrosine hydroxylase levels. The moderate to severe DA toxicity associated with the different doses of methamphetamine was not prevented by any dose of mephedrone but was, in fact, significantly enhanced. The hyperthermia caused by combined treatment with mephedrone and methamphetamine was the same as seen after either drug alone. Mephedrone also enhanced the neurotoxic effects of amphetamine and 3,4-methylenedioxymethamphetamine on DA nerve endings. In contrast, nomifensine protected against methamphetamine-induced neurotoxicity. As mephedrone increases methamphetamine neurotoxicity, the present results suggest that it interacts with the DAT in a manner unlike that of other typical DAT inhibitors. The relatively innocuous effects of mephedrone alone on DA nerve endings mask a potentially dangerous interaction with drugs that are often co-abused with it, leading to heightened neurotoxicity. © 2012 International Society for Neurochemistry.

Effects of albendazole combined with TSII-A (a Chinese herb compound) on optic neuritis caused by Angiostrongylus cantonensis in BALB/c mice.

PubMed

Feng, Feng; Feng, Ying; Liu, Zhen; Li, Wei-Hua; Wang, Wen-Cong; Wu, Zhong-Dao; Lv, Zhiyue

2015-11-25

Angiostrongylus cantonensis (A. cantonensis) infection can lead to optic neuritis, retinal inflammation, damage to ganglion cells, demyelination of optic nerve and visual impairment. Combined therapy of albendazole and dexamethasone is a common treatment for the disease in the clinic, but it plays no role in vision recovery. Therefore, it has been necessary to explore alternative therapies to treat this disease. Previous studies reported the neuro-productive effects of two constituents of Danshen (a Chinese herb)-tanshinone II-A (TSII-A) and cryptotanshinone (CPT), and this study aims to evaluate the impacts of TSII-A or CPT combined with albendazole on optic neuritis caused by A. cantonensis infection in a murine model. To assess the effects of TSII-A or CPT combined with albendazole on optic neuritis due to the infection, mice were divided into six groups, including the normal control group, infection group and four treatment groups (albendazole group, albendazole combined with dexamethasone group, albendazole combined with CPT group and albendazole combined with TSII-A group). The infection group and treatment groups were infected with A. cantonensis and the treatment groups received interventions from 14 dpi (days post infection), respectively. At 21 dpi, the visual acuity of mice in each group was examined by visual evoked potential (VEP). The pathologic alteration of the retina and optic nerve were observed by hematoxylin and eosin (H&E) staining and transmission electronic microscopy (TEM). Infection of A. cantonensis caused prolonged VEP latency, obvious inflammatory cell infiltration in the retina, damaged retinal ganglions and retinal swelling, followed by optic nerve fibre demyelination and a decreasing number of axons at 21 dpi. In treatment groups, albendazole could not alleviate the above symptoms; albendazole combined with dexamethasone lessened the inflammation of the retina, but was futile for the other changes; however, albendazole combined with CPT and albendazole combined with TSII-A showed obvious effects on the recovery of prolonged VEP latency, destruction and reduction of ganglion cells, optic nerve demyelination and axon loss. Compared with albendazole-CPT compound, albendazole combined with TSII-A was more effective. The current study demonstrates that albendazole combined with TSII-A plays a more effective role in treating optic neuritis caused by A. cantonensis in mice than with dexamethasone, as applied in conventional treatment, indicating that albendazole combined with TSII-A might be an alternate therapy for this parasitic disease in the clinic.

Intramuscular nerve damage in lacerated skeletal muscles may direct the inflammatory cytokine response during recovery.

PubMed

Pereira, Barry P; Tan, Bee Leng; Han, Hwan Chour; Zou, Yu; Aung, Khin Zarchi; Leong, David T

2012-07-01

The expression of inflammatory cytokines and growth factors in surgically repaired lacerated muscles over a 12-week recovery phase was investigated. We hypothesized that these expression levels are influenced by both neural and muscular damage within lacerated muscles. Microarrays were confirmed with reverse transcription-polymerase chain reaction assays and histology of biopsies at the lesion of three simulated lacerated muscle models in 130 adult rats. The lacerated medial gastrocnemius with the main intramuscular nerve branch either cut (DN), crushed but leaving an intact nerve sheath (RN); or preserved intact (PN) were compared. At 4 weeks, DN had a higher number of interleukins up-regulated. DN and RN also had a set of Bmp genes significantly expressed between 2 and 8 weeks (P ≤ 0.05). By 12 weeks, DN had a poorer and slower myogenic recovery and greater fibrosis formation correlating with an up-regulation of the Tgf-β gene family. DN also showed poorer re-innervation with higher mRNA expression levels of nerve growth factor (Ngf) and brain-derived neurotrophin growth factor (Bdnf) over RN and PN. This study demonstrates that the inflammatory response over 12 weeks in lacerated muscles may be directed by the type of intramuscular nerve damage, which can influence the recovery at the lesion site. Inflammatory-related genes associated to the type of intramuscular nerve damage include Gas-6, Artemin, Fgf10, Gdf8, Cntf, Lif, and Igf-2. qPCR also found up-regulation of Bdnf (1-week), neurotrophin-3 (2w), Lif (4w), and Ngf (4w, 8w) mRNA expressions in DN, making them possible candidates for therapeutic treatment to arrest the poor recovery in muscle lacerations (250). Copyright © 2012 Wiley Periodicals, Inc.

Results of a systematic literature review of treatment modalities for jugulotympanic paraganglioma, stratified per Fisch class.

PubMed

Jansen, T T G; Timmers, H J L M; Marres, H A M; Kaanders, J H A M; Kunst, H P M

2018-04-01

Key for successful jugulotympanic paraganglioma management is a personalised approach aiming for the best practice for each individual patient. To this end, a systematic review is performed, evaluating the local control and complication rates for the different treatment modalities stratified by the broadly accepted Fisch classification. A systematic literature review according to the PRISMA statement was performed. A detailed overview of individual treatment outcomes per Fisch class is provided. Local control, cranial nerve damage, complications, function recovery. Eighteen studies were selected, resembling 83 patients treated with radiotherapy and 299 with surgery. Excellent local control was found post-surgery for class A and B tumours, and risk of cranial nerve damage was <1%. For class C1-4 tumours, local control was 80%-95% post-surgery (84% post-radiotherapy), and cranial nerve damage was found in 71%-76% (none post-radiotherapy; P < .05). There was no difference in treatment outcomes between tumours of different C class. For class C1-4De/Di tumours, local control was 38%-86% (98% post-radiotherapy; P < .05) and cranial nerve damage/complication rates were 67%-100% (3% post-radiotherapy; P < .05). C1-4DeDi tumours showed lesser local control and cranial nerve damage rates when compared to C1-4De tumours. An individual risk is constituted for surgery and radiotherapy, stratified per Fisch class. For class A and B tumours, surgery is a suitable treatment option. For class C and D tumours, radiotherapy results in lower complication rates and similar or better local control rates when compared to the surgical group. © 2017 John Wiley & Sons Ltd.

Cardiovascular Regulation in Obstructive Sleep Apnea

PubMed Central

Ziegler, Michael G.; Milic, Milos; Elayan, Hamzeh

2011-01-01

The majority of patients with obstructive sleep apnea (OSA) suffer from hypertension as a complication of both the metabolic syndrome and OSA. In animal studies, intermittent hypoxia that simulates changes seen in OSA leads to chemoreceptor and chromaffin cell stimulation of sympathetic nerve activity, endothelial damage and impaired blood pressure modulation. Human studies reveal activation of sympathetic nerves, endothelial damage and exaggerated pressor responses to sympathetic neurotransmitters and endothelin. Although treatment of the OSA normalizes sympathetic nerve responses, it only lowers blood pressure modestly. Agents that block the consequences of sympathetic over activity, such as β1 blockers and angiotensin antagonists have effectively lowered blood pressure. Diuretics have been less successful. Treatment of hypertensive patients with OSA usually requires consideration of both increased sympathetic nerve activity and the metabolic syndrome. PMID:22125570

Early corneal nerve damage and recovery following small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK).

PubMed

Mohamed-Noriega, Karim; Riau, Andri K; Lwin, Nyein C; Chaurasia, Shyam S; Tan, Donald T; Mehta, Jodhbir S

2014-03-25

We compared early corneal nerve changes after small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK). A total of 12 rabbits underwent LASIK in one eye and SMILE in the fellow eye. Baseline and follow-up evaluations at 1, 2, and 4 weeks postoperatively were performed with in vivo confocal microscopy to evaluate 5 different areas within the treated zone: center, superior, inferior, nasal, and temporal. Cryosections of the corneas and whole mount of the extracted SMILE lenticules were analyzed with immunostaining of βIII-tubulin. One week after SMILE and LASIK, a decrease in nerve length and density was observed in all evaluated areas. A trend toward greater subbasal nerve length and density (SLD), more eyes with subbasal nerves (ESN), more eyes with subbasal nerves longer than 200 μm (SNL), and higher mean number of subbasal nerves by frame (NSN) in SMILE than in LASIK groups was observed at subsequent follow-up time points. Only the SMILE group showed a recovery of SLD, ESN, and NSN by week 4 (P > 0.05). A trend toward more eyes with sprouting subbasal nerves and greater mean number of sprouting nerves was observed in LASIK than in SMILE, indicating that more subbasal nerves were disrupted and undergoing regeneration after LASIK. Immunostaining at postoperative week 4 revealed a faster stromal nerve recovery in post-SMILE eyes compared to post-LASIK eyes. Our findings suggest that SMILE results in less nerve damage and faster nerve recovery than LASIK.

Intraoperative cranial nerve monitoring.

PubMed

Harper, C Michel

2004-03-01

The purpose of intraoperative monitoring is to preserve function and prevent injury to the nervous system at a time when clinical examination is not possible. Cranial nerves are delicate structures and are susceptible to damage by mechanical trauma or ischemia during intracranial and extracranial surgery. A number of reliable electrodiagnostic techniques, including nerve conduction studies, electromyography, and the recording of evoked potentials have been adapted to the study of cranial nerve function during surgery. A growing body of evidence supports the utility of intraoperative monitoring of cranial nerve nerves during selected surgical procedures.

Facial Nerve Schwannoma: A Case Report, Radiological Features and Literature Review.

PubMed

Pilloni, Giulia; Mico, Barbara Massa; Altieri, Roberto; Zenga, Francesco; Ducati, Alessandro; Garbossa, Diego; Tartara, Fulvio

2017-12-22

Facial nerve schwannoma localized in the middle fossa is a rare lesion. We report a case of a facial nerve schwannoma in a 30-year-old male presenting with facial nerve palsy. Magnetic resonance imaging (MRI) showed a 3 cm diameter tumor of the right middle fossa. The tumor was removed using a sub-temporal approach. Intraoperative monitoring allowed for identification of the facial nerve, so it was not damaged during the surgical excision. Neurological clinical examination at discharge demonstrated moderate facial nerve improvement (Grade III House-Brackmann).

Diabetic Nerve Problems

MedlinePlus

... the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. ... change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling ...

Prevalence of Obesity in Carpal Tunnel Syndrome Patients: A Cross-Sectional Survey.

PubMed

Mansoor, Salman; Siddiqui, Maimoona; Mateen, Farrukh; Saadat, Shoab; Khan, Zarak H; Zahid, Mehr; Khan, Hamza H; Malik, Shuja A; Assad, Salman

2017-07-26

Carpal tunnel syndrome (CTS) is the most common compressive entrapment neuropathy caused by the compression of the median nerve at the wrist space known as the carpal tunnel. The epidemiologic factors related to CTS include genetic, medical, social, vocational, and demographic factors. The common symptoms experienced include pain, paresthesia, and numbness in the median nerve distribution. If left untreated, it can lead to irreversible median nerve damage, causing a loss of hand function. Body mass index (BMI) has been attributed as a risk factor for the development of CTS. We planned to determine the frequency of obesity among CTS patients in the neurophysiology department of a tertiary care center in Islamabad, Pakistan. The survey was designed as a cross-sectional descriptive study from March 2016 to August 2016 using a consecutive nonprobability sampling technique. A total of 112 patients with a mean age of 54 ± 5 years were included in the study. In the study population, 39 patients (35 percent) were males and 73 were females (65 percent). Based on BMI, 74 patients (66 percent) had a normal weight and 38 (34 percent) were obese. The frequency of obesity in our study was 34 percent, excluding the other comorbid conditions, which is quite high. Targeted therapy in those with CTS should also include weight reduction measures because obesity poses a cause-and-effect relationship for both the severity and the pathogenesis of CTS.

Neuroprotective Effects of Galantamine on Nerve Agent-Induced Neuroglial and Biochemical Changes.

PubMed

Golime, RamaRao; Palit, Meehir; Acharya, J; Dubey, D K

2018-05-01

Neuroprotection from nerve agent such as soman-induced neural damage is a major challenge for existing drugs. Nerve agent exposure can cause many neural effects in survivors arising mainly due to acetylcholinesterase (AChE) inhibition or death within minutes. Unraveling the mechanisms underlying the nerve agent-induced multiple neurological effects is useful to develop better and safe drugs. The present study aimed to understand the molecular response during soman exposure and to evaluate the neuroprotective efficacy of galantamine on nerve agent-induced neurotoxic changes. mRNA expression studies using quantitative real-time PCR revealed significant changes in S-100β, Gfap, c-fos, and Bdnf in the hippocampus and piriform cortex after soman (90 μg/kg, s.c) exposure. Immunoblot analysis showed acute soman exposure significantly increased the protein levels of neuroglial markers (S100-β and GFAP); c-Fos and protein oxidation in discrete rat brain areas indicate their role in nerve agent-induced neurotoxicity. Induction of BDNF levels during soman exposure may indicate the recovery mechanisms activation. AChE was inhibited in the blood and brain up to 82% after soman exposure. Antidotal treatment with galantamine alone (3 mg/kg) and galantamine plus atropine (10 mg/kg) has protected animals from nerve agent-induced intoxication, death, and soman-inhibited AChE up to 45% in the blood and brain. Animal received galantamine displayed increased levels of neuroprotective genes (nAChRα-7, Bcl-2, and Bdnf) in the brain suggest the neuroprotective value of galantamine. Neuroglial changes, c-Fos, and protein oxidation levels significantly reduced after galantamine and galantamine plus atropine treatment indicate their potential antidotal value in nerve agent treatment.

Effect of diet induced obesity or type 1 or type 2 diabetes on corneal nerves and peripheral neuropathy in C57Bl/6J mice

PubMed Central

Yorek, Matthew S.; Obrosov, Alexander; Shevalye, Hanna; Holmes, Amey; Harper, Matthew M.; Kardon, Randy H.; Yorek, Mark A.

2015-01-01

We determined the impact diet induced obesity (DIO) and types 1 and 2 diabetes has on peripheral neuropathy with emphasis on corneal nerve structural changes in C57Bl/6J mice. Endpoints examined included nerve conduction velocity, response to thermal and mechanical stimuli and innervation of the skin and cornea. DIO mice and to a greater extent type 2 diabetic mice were insulin resistant. DIO and both types 1 and 2 diabetic mice developed motor and sensory nerve conduction deficits. In the cornea of DIO and type 2 diabetic mice there was a decrease in sub-epithelial corneal nerves, innervation of the corneal epithelium and corneal sensitivity. Type 1 diabetic mice did not present with any significant changes in corneal nerve structure until after 20 weeks of hyperglycemia. DIO and type 2 diabetic mice developed corneal structural damage more rapidly than type 1 diabetic mice even though hemoglobin A1C values were significantly higher in type 1 diabetic mice. This suggests that DIO with or without hyperglycemia contributes to development and progression of peripheral neuropathy and nerve structural damage in the cornea. PMID:25858759

What is the Best Strategy on Detection of Cornea Neuropathy in People with Diabetes? Recent Advances in Potential Measurements.

PubMed

Lv, Ying; Zhao, Shaozhen

2018-03-26

There are well-acknowledged clinical or pre-clinical measurements concerning diabetic peripheral neuropathy(DPN). The current gold standard for diagnosis of diabetic peripheral neuropathy is nerve conduction suitable for detecting large nerve fiber function[1] and intraepidermal nerve fiber density assessment for small fiber damage evaluation[2]. The lack of a sensitive, non-invasive, and repeatable endpoint to measure changes in small nerve fibers is a major factor holding back clinical trials for the treatment of diabetic peripheral neuropathy. As cornea is the most densely innerved tissue, assessing corneal nerves' structure and function will be promising to predict and assess the degree of DPN [3]. In the diabetic micro-environment, damaged corneal nerves lead to decreased corneal sensitivity, both of which resulting in abnormal tear function. According to this theory, the measurements of nerve structure, corneal sensitivity, tear secretion and tear components, to some extent, can reveal and assess the state of corneal neuropathy. This review focuses on summarizing the knowledge of the latest detective methods of diabetic corneal neuropathy, popular in use or possible to further in study and be applied into clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

Diffuse reflectance spectroscopy for optical nerve identification. Preliminary ex vivo results for feedback controlled oral and maxillofacial laser surgery

NASA Astrophysics Data System (ADS)

Stelzle, Florian; Zam, Azhar; Adler, Werner; Douplik, Alexandre; Tangermann-Gerk, Katja; Nkenke, Emeka; Neukam, Friedrich Wilhelm; Schmidt, Michael

Objective: Laser surgery has many advantages. However, due to a lack of haptic feedback it is accompanied by the risk of iatrogenic nerve damage. The aim of this study was to evaluate the possibilities of optical nerve identification by diffuse reflectance spectroscopy to set the base for a feedback control system to enhance nerve preservation in oral and maxillofacial laser surgery. Materials and Methods: Diffuse reflectance spectra of nerve tissue, skin, mucosa, fat tissue, muscle, cartilage and bone (15120 spectra) of ex vivo pig heads were acquired in the wavelength range of 350-650 nm. Tissue differentiation was performed by principal components analysis (PCA) followed by linear discriminant analysis (LDA). Specificity and sensitivity were calculated by receiver operating characteristic (ROC) analysis and the area under curve (AUC). Results: Nerve tissue could correctly be identified and differed from skin, mucosa, fat tissue, muscle, cartilage and bone in more than 90% of the cases (AUC results) with a specificity of over 78% and a sensitivity of more than 86%. Conclusion: Nerve tissue can be identified by diffuse reflectance spectroscopy with high precision and reliability. The results may set the base for a feedback system to prevent iatrogenic nerve damage performing oral and maxillofacial laser surgery.

Radiation-induced ocular motor cranial nerve palsies in patients with pituitary tumor.

PubMed

Vaphiades, Michael S; Spencer, Sharon A; Riley, Kristen; Francis, Courtney; Deitz, Luke; Kline, Lanning B

2011-09-01

Radiation therapy is often used in the treatment of pituitary tumor. Diplopia due to radiation damage to the ocular motor cranial nerves has been infrequently reported as a complication in this clinical setting. Retrospective case series of 6 patients (3 men and 3 women) with pituitary adenoma, all of whom developed diplopia following transsphenoidal resection of pituitary adenoma with subsequent radiation therapy. None had evidence of tumor involvement of the cavernous sinus. Five patients developed sixth nerve palsies, 3 unilateral and 2 bilateral, and in 1 patient, a sixth nerve palsy was preceded by a fourth cranial nerve palsy. One patient developed third nerve palsy. Five of the 6 patients had a growth hormone-secreting pituitary tumor with acromegaly. Following transsphenoidal surgery in all 6 patients (2 had 2 surgeries), 4 had 2 radiation treatments consisting of either radiosurgery (2 patients) or external beam radiation followed by radiosurgery (2 patients). Patients with pituitary tumors treated multiple times with various forms of radiation therapy are at risk to sustain ocular motor cranial nerve injury. The prevalence of acromegalic patients in this study reflects an aggressive attempt to salvage patients with recalcitrant growth hormone elevation and may place the patient at a greater risk for ocular motor cranial nerve damage.

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

PubMed

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.

Chemoresponsiveness and breath physiology in anosmia.

PubMed

Mazzatenta, Andrea; Pokorski, Mieczyslaw; Montinaro, Danilo; Di Giulio, Camillo

2015-01-01

Anosmia is a model to study the interaction among chemoreception systems. In the head injury, the traumatic irreversible anosmia caused by damage to olfactory nerve fibers and brain regions is of enviable research interest. In this study, psychophysiological tests for a comprehensive assessment of olfactory function were utilized to investigate anosmia, together with a new technique based on the breath real-time monitoring of volatile organic compounds (VOCs). We applied the breath and VOCs analysis to investigate chemoresponsiveness in the long-term irreversible post-traumatic anosmia.

Retinal nerve fiber layer thickness and neuropsychiatric manifestations in systemic lupus erythematosus.

PubMed

Shulman, S; Shorer, R; Wollman, J; Dotan, G; Paran, D

2017-11-01

Background Cognitive impairment is frequent in systemic lupus erythematosus. Atrophy of the corpus callosum and hippocampus have been reported in patients with systemic lupus erythematosus, and diffusion tensor imaging studies have shown impaired white matter integrity, suggesting that white matter damage in systemic lupus erythematosus may underlie the cognitive impairment as well as other neuropsychiatric systemic lupus erythematosus manifestations. Retinal nerve fiber layer thickness, as assessed by optical coherence tomography, has been suggested as a biomarker for white matter damage in neurologic disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. Retinal nerve fiber layer thinning may occur early, even in patients with mild clinical symptoms. Aim The objective of this study was to assess the association of retinal nerve fiber layer thickness, as a biomarker of white matter damage in systemic lupus erythematosus patients, with neuropsychiatric systemic lupus erythematosus manifestations, including cognitive impairment. Methods Twenty-one consecutive patients with systemic lupus erythematosus underwent neuropsychological testing using a validated computerized battery of tests as well as the Rey-Auditory verbal learning test. All 21 patients, as well as 11 healthy, age matched controls, underwent optical coherence tomography testing to assess retinal nerve fiber layer thickness. Correlations between retinal nerve fiber layer thickness and results in eight cognitive domains assessed by the computerized battery of tests as well as the Rey-Auditory verbal learning test were assessed in patients with systemic lupus erythematosus, with and without neuropsychiatric systemic lupus erythematosus, and compared to retinal nerve fiber layer thickness in healthy controls. Results No statistically significant correlation was found between retinal nerve fiber layer thickness in patients with systemic lupus erythematosus as compared to healthy controls. When evaluating by subgroups, no correlation was found between patients with or without neuropsychiatric systemic lupus erythematosus or cognitive impairment and retinal nerve fiber layer thickness. Conclusion Retinal nerve fiber layer thickness of systemic lupus erythematosus patients was not found to be statistically different compared to controls. Within systemic lupus erythematosus patients there was no correlation between retinal nerve fiber layer thickness and cognitive impairment or other neuropsychiatric systemic lupus erythematosus manifestations.

Neurophysiological intraoperative monitoring during an optic nerve schwannoma removal.

PubMed

San-Juan, Daniel; Escanio Cortés, Manuel; Tena-Suck, Martha; Orozco Garduño, Adolfo Josué; López Pizano, Jesús Alejandro; Villanueva Domínguez, Jonathan; Fernández Gónzalez-Aragón, Maricarmen; Gómez-Amador, Juan Luis

2017-10-01

This paper reports the case of a patient with optic nerve schwannoma and the first use of neurophysiological intraoperative monitoring of visual evoked potentials during the removal of such tumor with no postoperative visual damage. Schwannomas are benign neoplasms of the peripheral nervous system arising from the neural crest-derived Schwann cells, these tumors are rarely located in the optic nerve and the treatment consists on surgical removal leading to high risk of damage to the visual pathway. Case report of a thirty-year-old woman with an optic nerve schwannoma. The patient underwent surgery for tumor removal on the left optic nerve through a left orbitozygomatic approach with intraoperative monitoring of left II and III cranial nerves. We used Nicolet Endeavour CR IOM (Carefusion, Middleton WI, USA) to performed visual evoked potentials stimulating binocularly with LED flash goggles with the patient´s eyes closed and direct epidural optic nerve stimulation delivering rostral to the tumor a rectangular current pulse. At follow up examinations 7 months later, the left eye visual acuity was 20/60; Ishihara score was 8/8 in both eyes; the right eye photomotor reflex was normal and left eye was mydriatic and arreflectic; optokinetic reflex and ocular conjugate movements were normal. In this case, the epidural direct electrical stimulation of optic nerve provided stable waveforms during optic nerve schwannoma resection without visual loss.

Eye-Directed Overpressure Airwave-Induced Trauma Causes Lasting Damage to the Anterior and Posterior Globe: A Model for Testing Cell-Based Therapies

PubMed Central

Bricker-Anthony, Courtney; Hines-Beard, Jessica

2016-01-01

Abstract Purpose: Characterization of the response of the Balb/c mouse to an eye-directed overpressure airwave, with the hypothesis that this mouse strain and model is useful for testing potential therapeutics for the treatment of traumatic eye injury. Methods: The left eyes of adult Balb/c mice were exposed to an eye-directed overpressure airwave. Intraocular pressure (IOP) was measured and eyes were inspected for gross pathology changes. Optical coherence tomography and histology were used to examine the structural integrity of the retina and optic nerve. Immunohistochemistry, in vivo molecular fluorophores, and a multiplex enzyme-linked immunosorbent assay were utilized to identify changes in cell death, neuroinflammation, and oxidative stress. Results: This model induced a transient increase in IOP, corneal injuries, infrequent large retinal detachments, retinal pigment epithelium (RPE) vacuolization, glial reactivity, and retinal cell death. Both the corneal damage and RPE vacuolization persisted with time. Optic nerve degeneration occurred as early as 7 days postinjury and persisted out to 60 days. Retinal cell death, increased levels of reactive oxygen species, and neuroinflammation were detected at 7 days postinjury. Conclusions: The injury profile of the Balb/c mouse is consistent with commonly observed pathologies in blast-exposed patients. The damage is throughout the eye and persistent, making this mouse model useful for testing cell-based therapies. PMID:26982447

Optic nerve sheath fenestration using a Raman-shifted alexandrite laser

PubMed Central

Kozub, John; Shen, Jin-H.; Joos, Karen M.; Prasad, Ratna; Hutson, M. Shane

2016-01-01

Background and Objective Optic nerve sheath fenestration is an established procedure for relief of potentially damaging overpressure on the optic nerve resulting from idiopathic intracranial hypertension. Prior work showed that a mid-IR free-electron laser could be delivered endoscopically and used to produce an effective fenestration. This study evaluates the efficacy of fenestration using a table-top mid-IR source based on a Raman-shifted alexandrite (RSA) laser. Study Design/Materials and Methods Porcine optic nerves were ablated using light from an RSA laser at wavelengths of 6.09, 6.27 and 6.43 μm and pulse energies up to 3 mJ using both free-space and endoscopic beam delivery through 250-μm I.D. hollow-glass waveguides. Waveguide transmission was characterized, ablation thresholds and etch rates were measured, and the efficacy of endoscopic fenestration was evaluated for ex vivo exposures using both optical coherence tomography and histological analysis. Results Using endoscopic delivery, the RSA laser can effectively fenestrate porcine optic nerves. Performance was optimized at a wavelength of 6.09 μm and delivered pulse energies of 0.5-0.8 mJ (requiring 1.5-2.5 mJ to be incident on the waveguide). Under these conditions, the ablation threshold fluence was 0.8 ± 0.2 J/cm2, the ablation rate was 1-4 μm/pulse, and the margins of ablation craters showed little evidence of thermal or mechanical damage. Nonetheless, nominally identical exposures yielded highly variable ablation rates. This led to fenestrations that ranged from too deep to too shallow – either damaging the underlying optic nerve or requiring additional exposure to cut fully through the sheath. Of 48 excised nerves subjected to fenestration at 6.09 μm, 16 ex vivo fenestrations were judged as good, 23 as too deep, and 9 as too shallow. Conclusions Mid-IR pulses from the RSA laser, propagated through a flexible hollow waveguide, are capable of cutting through porcine optic nerve sheaths in surgically relevant times with reasonable accuracy and low collateral damage. This can be accomplished at wavelengths of 6.09 or 6.27 μm, with 6.09 μm slightly preferred. The depth of ex vivo fenestrations was difficult to control, but excised nerves lack a sufficient layer of cerebrospinal fluid that would provide an additional margin of safety in actual patients. PMID:27020001

Laser-activated protein bands for peripheral nerve repair

NASA Astrophysics Data System (ADS)

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.

Subclavian vein pacing and venous pressure waveform measurement for phrenic nerve monitoring during cryoballoon ablation of atrial fibrillation.

PubMed

Ghosh, Justin; Singarayar, Suresh; Kabunga, Peter; McGuire, Mark A

2015-06-01

The phrenic nerves may be damaged during catheter ablation of atrial fibrillation. Phrenic nerve function is routinely monitored during ablation by stimulating the right phrenic nerve from a site in the superior vena cava (SVC) and manually assessing the strength of diaphragmatic contraction. However the optimal stimulation site, method of assessing diaphragmatic contraction, and techniques for monitoring the left phrenic nerve have not been established. We assessed novel techniques to monitor phrenic nerve function during cryoablation procedures. Pacing threshold and stability of phrenic nerve capture were assessed when pacing from the SVC, left and right subclavian veins. Femoral venous pressure waveforms were used to monitor the strength of diaphragmatic contraction. Stable capture of the left phrenic nerve by stimulation in the left subclavian vein was achieved in 96 of 100 patients, with a median capture threshold of 2.5 mA [inter-quartile range (IQR) 1.4-5.0 mA]. Stimulation of the right phrenic nerve from the subclavian vein was superior to stimulation from the SVC with lower pacing thresholds (1.8 mA IQR 1.4-3.3 vs. 6.0 mA IQR 3.4-8.0, P < 0.001). Venous pressure waveforms were obtained in all patients and attenuation of the waveform was always observed prior to onset of phrenic nerve palsy. The left phrenic nerve can be stimulated from the left subclavian vein. The subclavian veins are the optimal sites for phrenic nerve stimulation. Monitoring the femoral venous pressure waveform is a novel technique for detecting impending phrenic nerve damage. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

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

PubMed

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 patients with cranial nerve involvement.

Aberrant regeneration of the third cranial nerve.

PubMed

Shrestha, U D; Adhikari, S

2012-01-01

Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

[Application value of corneal hysteresis in diagnosis and treatment of glaucoma].

PubMed

He, L Y; Liang, L; Zhu, M N

2017-02-11

Glaucoma is the first leading cause of irreversible blindness world widely, but the pathogenesis was still unclear. The collagen fibers from cornea and sclera connect to each other and both of them have similar extracellular matrix components. The biomechanical characteristics of optic nerve lamina cribrosa may associated with the biomechanical properties of the cornea. Therefore, the study of corneal physiological can indirectly reflex the compression and damage in optic nerve lamina cribrosa. The technical developments in corneal hysteresis examination had been updated these years constantly. Many researches implicated that low corneal hysteresis involved in pathogenesis and progression of glaucoma which refresh our recognition of the relationship between cornea and glaucoma. This review summarized the characteristics of corneal hysteresis, the examination and the connection with glaucoma to provide the reference for clinical work. (Chin J Ophthalmol, 2017, 53: 140-143) .

Facial diplegia, pharyngeal paralysis, and ophthalmoplegia after a timber rattlesnake envenomation.

PubMed

Madey, Jason J; Price, Amanda B; Dobson, Joseph V; Stickler, David E; McSwain, S David

2013-11-01

The timber rattlesnake, also known as Crotalus horridus, is well known to cause significant injury from toxins stored within its venom. During envenomation, toxic systemic effects immediately begin to cause damage to many organ systems including cardiovascular, hematologic, musculoskeletal, respiratory, and neurologic. One defining characteristic of the timber rattlesnake is a specific neurotoxin called crotoxin, or the "canebrake toxin," which is a potent β-neurotoxin affecting presynaptic nerves that can cause paralysis by inhibiting appropriate neuromuscular transmission. We present an unusual case of an 8-year-old boy bitten twice on his calf by a timber rattlesnake, who presented with a life-threatening envenomation and suffered multisystem organ failure as well as a prominent presynaptic neurotoxicity resulting in facial diplegia, pharyngeal paralysis, and ophthalmoplegia.

The contribution of the sclera and lamina cribrosa to the pathogenesis of glaucoma: Diagnostic and treatment implications.

PubMed

Quigley, Harry A

2015-01-01

Glaucoma, the second most common cause of world blindness, results from loss of retinal ganglion cells (RGC). RGC die as a consequence of injury to their axons, as they pass through the transition between the environment within the eye and that of the retrobulbar optic nerve, as they course to central visual centers. At the optic nerve head (ONH), axonal transport becomes abnormal, at least in part due to the effect of strain induced by intraocular pressure (IOP) on the sclera and ONH. Animal glaucoma models provide the ability to study how alterations in ocular connective tissues affect this pathological process. New therapeutic interventions are being investigated to mitigate glaucoma blindness by modifying the remodeling of ocular tissues in glaucoma. Some genetically altered mice are resistant to glaucoma damage, while treatment of the sclera with cross-linking agents makes experimental mouse glaucoma damage worse. Inhibition of transforming growth factor β activity is strikingly protective. Treatments that alter the response of ocular connective tissues to IOP may be effective in protecting those with glaucoma from vision loss. © 2015 Elsevier B.V. All rights reserved.

Cellular mechanisms of noise-induced hearing loss.

PubMed

Kurabi, Arwa; Keithley, Elizabeth M; Housley, Gary D; Ryan, Allen F; Wong, Ann C-Y

2017-06-01

Exposure to intense sound or noise can result in purely temporary threshold shift (TTS), or leave a residual permanent threshold shift (PTS) along with alterations in growth functions of auditory nerve output. Recent research has revealed a number of mechanisms that contribute to noise-induced hearing loss (NIHL). The principle cause of NIHL is damage to cochlear hair cells and associated synaptopathy. Contributions to TTS include reversible damage to hair cell (HC) stereocilia or synapses, while moderate TTS reflects protective purinergic hearing adaptation. PTS represents permanent damage to or loss of HCs and synapses. While the substrates of HC damage are complex, they include the accumulation of reactive oxygen species and the active stimulation of intracellular stress pathways, leading to programmed and/or necrotic cell death. Permanent damage to cochlear neurons can also contribute to the effects of NIHL, in addition to HC damage. These mechanisms have translational potential for pharmacological intervention and provide multiple opportunities to prevent HC damage or to rescue HCs and spiral ganglion neurons that have suffered injury. This paper reviews advances in our understanding of cellular mechanisms that contribute to NIHL and their potential for therapeutic manipulation. Published by Elsevier B.V.

Prolonged high fat diet ingestion, obesity, and type 2 diabetes symptoms correlate with phenotypic plasticity in myenteric neurons and nerve damage in the mouse duodenum

PubMed Central

Stenkamp-Strahm, Chloe M.; Nyavor, Yvonne E. A.; Kappmeyer, Adam J.; Horton, Sarah; Gericke, Martin; Balemba, Onesmo B.

2015-01-01

Symptoms of diabetic gastrointestinal dysmotility indicate neuropathy of the enteric nervous system. Long-standing diabetic enteric neuropathy has not been fully characterized, however. We used prolonged high fat diet ingestion (20 weeks) in a mouse model to mimic human obese and type 2 diabetic conditions, and analyzed changes seen in neurons of the duodenal myenteric plexus. Ganglionic and neuronal size, number of neurons per ganglionic area, density indices of neuronal phenotypes (immunoreactive nerve cell bodies and varicosities per ganglion or tissue area) and nerve injury were measured. Findings were compared with results previously seen in mice fed the same diet for 8 weeks. Compared to mice fed standard chow, those on a prolonged high fat diet had smaller ganglionic and cell soma areas. Myenteric VIP- and ChAT-immunoreactive density indices were also reduced. Myenteric nerve fibers were markedly swollen and cytoskeletal protein networks were disrupted. The number of nNOS nerve cell bodies per ganglia was increased, contrary to the reduction previously seen after 8 weeks, but the density index of nNOS varicosities was reduced. Mice fed high fat and standard chow diets experienced an age-related reduction in total neurons, biasing towards neurons of sensory phenotype. Meanwhile ageing was associated with an increase in excitatory neuronal markers. Collectively, these results support a notion that nerve damage underlies diabetic symptoms of dysmotility, and reveals adaptive ENS responses to the prolonged ingestion of a high fat diet. This highlights a need to mechanistically study long-term diet-induced nerve damage and age-related impacts on the ENS. PMID:25722087

Central muscarinic cholinergic regulation of the systemic inflammatory response during endotoxemia

PubMed Central

Pavlov, Valentin A.; Ochani, Mahendar; Gallowitsch-Puerta, Margot; Ochani, Kanta; Huston, Jared M.; Czura, Christopher J.; Al-Abed, Yousef; Tracey, Kevin J.

2006-01-01

TNF has a critical mediator role in inflammation and is an important therapeutic target. We recently discovered that TNF production is regulated by neural signals through the vagus nerve. Activation of this “cholinergic antiinflammatory pathway” inhibits the production of TNF and other cytokines and protects animals from the inflammatory damage caused by endotoxemia and severe sepsis. Here, we describe a role for central muscarinic acetylcholine receptors in the activation of the cholinergic antiinflammatory pathway. Central muscarinic cholinergic activation by muscarine, the M1 receptor agonist McN-A-343, and the M2 receptor antagonist methoctramine inhibited serum TNF levels significantly during endotoxemia. Centrally administered methoctramine stimulated vagus-nerve activity measured by changes in instantaneous heart-rate variability. Blockade of peripheral muscarinic receptors did not abolish antiinflammatory signaling through the vagus nerve, indicating that peripheral muscarinic receptors on immune cells are not required for the cytokine-regulating activities of the cholinergic antiinflammatory pathway. The role of central muscarinic receptors in activating the cholinergic antiinflammatory pathway is of interest for the use of centrally acting muscarinic cholinergic enhancers as antiinflammatory agents. PMID:16549778

Interaction of thyroid state and denervation on skeletal myosin heavy chain expression

NASA Technical Reports Server (NTRS)

Haddad, F.; Arnold, C.; Zeng, M.; Baldwin, K.

1997-01-01

The goal of this study was to examine the effects of altered thyroid state and denervation (Den) on skeletal myosin heavy chain (MHC) expression in the plantaris and soleus muscles. Rats were subjected to unilateral denervation (Den) and randomly assigned to one of three groups: (1) euthyroid; (2) hyperthyroid; (3) and hypothyroid. Denervation caused severe muscle atrophy and muscle-type specific MHC transformation. Denervation transformed the soleus to a faster muscle, and its effects required the presence of circulating thyroid hormone. In contrast, denervation transformed the plantaris to a slower muscle independently of thyroid state. Furthermore, thyroid hormone effects did not depend upon innervation status in the soleus, while they required the presence of the nerve in the plantaris. Collectively, these findings suggest that both thyroid hormone and intact nerve (a) differentially affect MHC transformations in fast and slow muscle; and (b) are important factors in regulating the optimal expression of both type I and IIB MHC genes. This research suggests that for patients with nerve damage and/or paralysis, both muscle mass and biochemical properties can also be affected by the thyroid state.

Cyclooxygenase-2 is an obligatory factor in methamphetamine-induced neurotoxicity.

PubMed

Thomas, David M; Kuhn, Donald M

2005-05-01

Methamphetamine causes persistent damage to dopamine nerve endings of the striatum. The mechanisms underlying its neurotoxicity are not fully understood, but considerable evidence points to oxidative stress as a probable mechanism. A recent microarray analysis of gene expression changes caused by methamphetamine revealed that cyclooxygenase-2 (COX-2) was induced along with its transcription factor CCAAT/enhancer-binding protein (Thomas DM, Francescutti-Verbeem DM, Liu X, and Kuhn DM, 2004). We report presently that methamphetamine increases striatal expression of COX-2 protein. Cyclooxygenase-1 (COX-1) expression was not changed. Mice bearing a null mutation of the gene for COX-2 were resistant to methamphetamine-induced neurotoxicity. COX-1 knockouts, like wild-type mice, showed extensive dopamine nerve terminal damage. Selective inhibitors of COX-1 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethyl pyrazole (SC-560)], COX-2 [N-[2-(cyclohexyloxy)-4-nitrophenyl] methanesulfonamide (NS-398), rofecoxib], or COX-3 (antipyrine) or a nonselective inhibitor of the COX-1/2 isoforms (ketoprofen) did not protect mice from neurotoxicity. Finally, methamphetamine did not change striatal prostaglandin E(2) content. Taken together, these data suggest that COX-2 is an obligatory factor in methamphetamine-induced neurotoxicity. The functional aspect of COX-2 that contributes to drug-induced neurotoxicity does not appear to be its prostaglandin synthetic capacity. Instead, the peroxidase activity associated with COX-2, which can lead to the formation of reactive oxygen species and dopamine quinones, can account for its role.

Concurrent targeting of nitrosative stress-PARP pathway corrects functional, behavioral and biochemical deficits in experimental diabetic neuropathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Negi, Geeta; Kumar, Ashutosh; Sharma, Shyam S., E-mail: sssharma@niper.ac.in

2010-01-01

Peroxynitrite mediated nitrosative stress, an indisputable initiator of DNA damage and overactivation of poly(ADP-ribose) polymerase (PARP), a nuclear enzyme activated after sensing DNA damage, are two crucial pathogenetic mechanisms in diabetic neuropathy. The intent of the present study was to investigate the effect of combination of a peroxynitrite decomposition catalyst (PDC), FeTMPyP and a PARP inhibitor, 4-ANI against diabetic peripheral neuropathy. The end points of evaluation of the study included motor nerve conduction velocity (MNCV) and nerve blood flow (NBF) for evaluating nerve functions; thermal hyperalgesia and mechanical allodynia for assessing nociceptive alterations, malondialdehyde and peroxynitrite levels to detect oxidativemore » stress-nitrosative stress; NAD concentration in sciatic nerve to assess overactivation of PARP. Additionally immunohistochemical studies for nitrotyrosine and Poly(ADP-ribose) (PAR) was also performed. Treatment with the combination of FeTMPyP and 4-ANI led to significant improvement in nerve functions and pain parameters and also attenuated the oxidative-nitrosative stress markers. Further, the combination also reduced the overactivation of PARP as evident from increased NAD levels and decreased PAR immunopositivity in sciatic nerve microsections. Thus, it can be concluded that treatment with the combination of a PDC and PARP inhibitor attenuates alteration in peripheral nerves in diabetic neuropathy (DN).« less

Fish oil supplementation prevents diabetes-induced nerve conduction velocity and neuroanatomical changes in rats.

PubMed

Gerbi, A; Maixent, J M; Ansaldi, J L; Pierlovisi, M; Coste, T; Pelissier, J F; Vague, P; Raccah, D

1999-01-01

Diabetic neuropathy has been associated with a decrease in nerve conduction velocity, Na,K-ATPase activity and characteristic histological damage of the sciatic nerve. The aim of this study was to evaluate the potential effect of a dietary supplementation with fish oil [(n-3) fatty acids] on the sciatic nerve of diabetic rats. Diabetes was induced by intravenous streptozotocin injection. Diabetic animals (n = 20) were fed a nonpurified diet supplemented with either olive oil (DO) or fish oil (DM), and control animals (n = 10) were fed a nonpurified diet supplemented with olive oil at a daily dose of 0.5 g/kg by gavage for 8 wk. Nerves were characterized by their conduction velocity, morphometric analysis and membrane Na, K-ATPase activity. Nerve conduction velocity, as well as Na,K-ATPase activity, was improved by fish oil treatment. A correlation was found between these two variables (R = 0.999, P < 0.05). Moreover, a preventive effect of fish oil was observed on nerve histological damage [endoneurial edema, axonal degeneration (by 10-15%) with demyelination]. Moreover, the normal bimodal distribution of the internal diameter of myelinated fibers was absent in the DO group and was restored in the DM group. These data suggest that fish oil therapy may be effective in the prevention of diabetic neuropathy.

Ultrasound-assisted endoscopic partial plantar fascia release.

PubMed

Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

2013-01-01

Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure.

Ultrasound-Assisted Endoscopic Partial Plantar Fascia Release

PubMed Central

Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

2013-01-01

Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure. PMID:24265989

Varicose vein therapy and nerve lesions.

PubMed

Hirsch, Tobias

2017-03-01

Treating varicose veins using endovenous thermal techniques - especially laser and radio frequency ablation - has emerged as an effective alternative to open surgery with stripping and high ligation. Even though these methods are very gentle and patient-friendly, they are nevertheless accompanied by risks and side effects. Compared to open surgical therapy, the risk of damage to peripheral and motor nerves is reduced; however, it still exists as a result of heat exposure and tumescent anaesthesia. Non-thermal methods that can be applied without tumescent anaesthesia have been introduced to the market. They pose a considerably lower risk of nerve lesions while proving to be much more effective. This paper investigates data on postoperative nerve damage and paraesthesia using internet research (PubMed). It analyses the current state of knowledge regarding non-thermal treatment methods and takes into account the latest developments in the use of cyanoacrylate to close insufficient saphenous veins.

Automated Diagnosis of Glaucoma Using Empirical Wavelet Transform and Correntropy Features Extracted From Fundus Images.

PubMed

Maheshwari, Shishir; Pachori, Ram Bilas; Acharya, U Rajendra

2017-05-01

Glaucoma is an ocular disorder caused due to increased fluid pressure in the optic nerve. It damages the optic nerve and subsequently causes loss of vision. The available scanning methods are Heidelberg retinal tomography, scanning laser polarimetry, and optical coherence tomography. These methods are expensive and require experienced clinicians to use them. So, there is a need to diagnose glaucoma accurately with low cost. Hence, in this paper, we have presented a new methodology for an automated diagnosis of glaucoma using digital fundus images based on empirical wavelet transform (EWT). The EWT is used to decompose the image, and correntropy features are obtained from decomposed EWT components. These extracted features are ranked based on t value feature selection algorithm. Then, these features are used for the classification of normal and glaucoma images using least-squares support vector machine (LS-SVM) classifier. The LS-SVM is employed for classification with radial basis function, Morlet wavelet, and Mexican-hat wavelet kernels. The classification accuracy of the proposed method is 98.33% and 96.67% using threefold and tenfold cross validation, respectively.

A new model for diffuse brain injury by rotational acceleration: I model, gross appearance, and astrocytosis.

PubMed

Gutierrez, E; Huang, Y; Haglid, K; Bao, F; Hansson, H A; Hamberger, A; Viano, D

2001-03-01

Rapid head rotation is a major cause of brain damage in automobile crashes and falls. This report details a new model for rotational acceleration about the center of mass of the rabbit head. This allows the study of brain injury without translational acceleration of the head. Impact from a pneumatic cylinder was transferred to the skull surface to cause a half-sine peak acceleration of 2.1 x 10(5) rad/s2 and 0.96-ms pulse duration. Extensive subarachnoid hemorrhages and small focal bleedings were observed in the brain tissue. A pronounced reactive astrogliosis was found 8-14 days after trauma, both as networks around the focal hemorrhages and more diffusely in several brain regions. Astrocytosis was prominent in the gray matter of the cerebral cortex, layers II-V, and in the granule cell layer and around the axons of the pyramidal neurons in the hippocampus. The nuclei of cranial nerves, such as the hypoglossal and facial nerves, also showed intense astrocytosis. The new model allows study of brain injuries from head rotation in the absence of translational influences.

Assessment of diabetic neuropathy with emission tomography and magnetic resonance spectroscopy.

PubMed

Rao, Harshvardhan; Gaur, Neeraj; Tipre, Dnyanesh

2017-04-01

Diabetic neuropathies (DNs) are nerve-damaging disorders associated with diabetes. They are commonly attributed to peripheral nerves and primarily affect the limbs of the patient. They cause altered sensitivity to external stimuli along with loss in balance and reflexes of the affected patient. DNs are associated with a variety of clinical manifestations including autonomic failure and are caused by poor management of blood sugar levels. Imaging modalities provide vital information about early physiological changes in DNs. This review summarizes contributions by various teams of scientists in developing imaging methods to assess physiological changes in DNs and ongoing clinical trials where imaging modalities are applied to evaluate therapeutic intervention in DNs. Development of PET, single photon emission computed tomography, and magnetic resonance spectroscopy methods over the past 20 years are reviewed in the diagnostic assessment of DNs. Abnormal radiotracer pharmacokinetics and neurometabolite spectra in affected organs confirm physiological abnormalities in DN. With the use of the Siemens Biograph mMR and GE Signa - 60 cm (PET/MRI scanner), simultaneous acquisition of physiological and anatomical information could enhance understanding of DNs and accelerate drug development.

Facial nerve paralysis associated with temporal bone masses.

PubMed

Nishijima, Hironobu; Kondo, Kenji; Kagoya, Ryoji; Iwamura, Hitoshi; Yasuhara, Kazuo; Yamasoba, Tatsuya

2017-10-01

To investigate the clinical and electrophysiological features of facial nerve paralysis (FNP) due to benign temporal bone masses (TBMs) and elucidate its differences as compared with Bell's palsy. FNP assessed by the House-Brackmann (HB) grading system and by electroneurography (ENoG) were compared retrospectively. We reviewed 914 patient records and identified 31 patients with FNP due to benign TBMs. Moderate FNP (HB Grades II-IV) was dominant for facial nerve schwannoma (FNS) (n=15), whereas severe FNP (Grades V and VI) was dominant for cholesteatomas (n=8) and hemangiomas (n=3). The average ENoG value was 19.8% for FNS, 15.6% for cholesteatoma, and 0% for hemangioma. Analysis of the correlation between HB grade and ENoG value for FNP due to TBMs and Bell's palsy revealed that given the same ENoG value, the corresponding HB grade was better for FNS, followed by cholesteatoma, and worst in Bell's palsy. Facial nerve damage caused by benign TBMs could depend on the underlying pathology. Facial movement and ENoG values did not correlate when comparing TBMs and Bell's palsy. When the HB grade is found to be unexpectedly better than the ENoG value, TBMs should be included in the differential diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Intrafascicular injection of ammonium sulfate and bupivacaine in peripheral nerves of neonatal and juvenile rats.

PubMed

Hertl, M C; Hagberg, P K; Hunter, D A; Mackinnon, S E; Langer, J C

1998-01-01

Regional nerve blocks are often used for the treatment of postoperative pain in children. Ammonium sulfate is a non-narcotic anesthetic agent, which has been reported to provide pain relief lasting days to weeks, with few reported side effects in adult studies. Prior to considering clinical use in children, the neurotoxicity of ammonium sulfate in 4-day and 3-week old rats was assessed and compared with that of bupivacaine. Each rat received a posterior tibial nerve intrafascicular injection (0.01 mL in 4-day-old and 0.02 mL in 3-week-old rats) using either 10% ammonium sulfate (n = 24 per age group), 0.5% bupivacaine (n = 18 per age group), 0.9% saline (n = 18 per age group), or 5% phenol (n = 18 per age group). A functional assessment by serial walking track analysis and a morphologic assessment by neurohistology were made. No abnormalities in serial walking track analysis and no structural nerve damage were detected after ammonium sulfate, bupivacaine, or saline injection. Bupivacaine caused mild focal changes in both age groups, which recovered by 8 weeks. Intrafascicular injection of ammonium sulfate was as safe as bupivacaine in this animal model. Further animal studies must be made before human trials are initiated.

Hydrocephalus

MedlinePlus

... support and help with the care of a child with hydrocephalus who has serious brain damage. ... such as meningitis or encephalitis Intellectual impairment Nerve damage (decrease in movement, sensation, function) Physical disabilities

[Surgery of lower third molars and lesions of the lingual nerve].

PubMed

Chiapasco, M; Pedrinazzi, M; Motta, J; Crescentini, M; Ramundo, G

1996-11-01

The authors describe a technical expedient applied during the removal of totally or partially impacted lower third molars, in order to prevent lingual nerve damage. EXPERIMENTAL ASSAY: Retrospective study. The sample includes 1835 extractions of totally or partially impacted lower third molars, performed on 1030 patients, 493 males and 537 females, aging between 12 and 72 years. All the operations were carried out under local anaesthesia with standardization of the surgical protocol. A mucoperiosteal paramarginal flap was used in case of germectomy, whereas a mucoperiosteal marginal flap with mesial releasing incision was used in case of fully mature teeth. Ostectomy and tooth sectioning were performed using a round and fissure bur respectively, assembled on a straight low-speed handpiece and under irrigation with sterile saline. The authors reported only one case of transient lingual nerve paresthesia (0.05%) which occurred in a 19-years old female presenting a totally impacted third molar mesial-lingual inclination. Symptoms disappeared spontaneously one week postoperatively. Therefore the overall incidence of permanent nerve damage was equal to 0%. The data reported in literature show a lingual nerve lesion incidence ranging between 0% and 22%. With this simple surgical expedient the incidence of permanent lingual damage was 0%. Thus, it is the authors' opinion that this simple expedient should be applied in all cases of impacted third molar removal.

In vitro laser nerve repair: protein solder strip irradiation or irradiation alone?

PubMed

Trickett, I; Dawes, J M; Knowles, D S; Lanzetta, M; Owen, E R

1997-01-01

This study investigated the potential of sutureless nerve repair using two promising laser fusion methods: direct 2 microns irradiation of the epineurium, and protein solder assisted epineurial fusion using a 800 nm laser. Laser anastomosis of the rat sciatic nerve was performed in vitro without stay sutures in two groups of six animals. In the first group, direct laser fusion used a pulsed Cr, Tm: YAG laser. In the second group an albumin-based fluid solder containing the dye indocyanine green was applied to the epineurium, then irradiated with a diode laser. These two techniques were compared with regards to coaptation success and axonal damage. Direct laser welding produced weak bonds despite microscopic investigation of the irradiated nerves showing fusion of the epineurium. The unsatisfactory bonding can be attributed to poor tissue overlap and insufficient protein in the thin epineurium denaturation of underlying axons was also observed. In contrast, the laser solder method produced successful welds with greatly reduced axonal damage, and significantly improved the tensile strength. This study confirmed the technical possibilities of sutureless nerve anastomosis. Laser activated solders enable stronger bonds, by the addition of protein to the anastomosis site, and less thermal damage to underlying tissue through selective absorption of laser energy by dye in the solder. Further in vivo studies are required before drawing final conclusions.

Longterm effects of cardiac mediastinal nerve cryoablation on neural inducibility of atrial fibrillation in canines.

PubMed

Leiria, Tiago Luiz Luz; Glavinovic, Tamara; Armour, J Andrew; Cardinal, René; de Lima, Gustavo Glotz; Kus, Teresa

2011-04-26

In canines, excessive activation of select mediastinal nerve inputs to the intrinsic cardiac nervous system induces atrial fibrillation (AF). Since ablation of neural elements is proposed as an adjunct to circumferential pulmonary vein ablation for AF, we investigated the short and long-term effects of mediastinal nerve ablation on AF inducibility. Under general anesthesia, in 11 dogs several mediastinal nerve sites were identified on the superior vena cava that, when stimulated electrically during the atrial refractory period, reproducibly initiated AF. Cryoablation of one nerve site was then performed and inducibility retested early (1-2 months post Cryo; n=7) or late (4 months post Cryo; n=4). Four additional dogs that underwent a sham procedure were retested 1 to 2 months post-surgery. Stimulation induced AF at 91% of nerve sites tested in control versus 21% nerve sites early and 54% late post-ablation (both P<0.05). Fewer stimuli were required to induce AF in controls versus the Early Cryo group; this capacity returned to normal values in the Late Cryo group. AF episodes were longer in control versus the Early or Late Cryo groups. Heart rate responses to vagal or stellate ganglion stimulation, as well as to local nicotine infusion into the right coronary artery, were similar in all groups. In conclusion, focal damage to intrinsic cardiac neuronal inputs causes short-term stunning of neuronal inducibility of AF without major loss of overall adrenergic or cholinergic efferent neuronal control. That recovery of AF inducibility occurs rapidly post-surgery indicates the plasticity of intrathoracic neuronal elements to focal injury. Copyright © 2011 Elsevier B.V. All rights reserved.

Midazolam as an anticonvulsant antidote for organophosphate intoxication− A pharmacotherapeutic appraisal

PubMed Central

Reddy, Sandesh D.; Reddy, Doodipala Samba

2015-01-01

SUMMARY Objective This review summarizes the therapeutic potential of midazolam as an anticonvulsant antidote for organophosphate (OP) intoxication. Methods Benzodiazepines are widely used for acute seizures and status epilepticus (SE), a neurological emergency of persistent seizures that can lead to severe neuronal damage or death. Midazolam is a benzodiazepine hypnotic with a rapid onset and short duration of action. Results Midazolam is considered the new drug of choice for persistent acute seizures and SE, including those caused by neurotoxic OPs and nerve agents. Midazolam is a positive allosteric modulator of synaptic GABA-A receptors in the brain. It potentiates GABAergic inhibition and thereby controls hyperexcitability and seizures. Midazolam is administered intravenously or intramuscularly to control acute seizures and SE. Due to its favorable pharmacokinetic features, midazolam is being considered as a replacement anticonvulsant for diazepam in the antidote kit for nerve agents. Clinical studies such as the recent RAMPART trial have confirmed the anticonvulsant efficacy of midazolam in SE in prehospital settings. Significance In experimental models, midazolam is effective when given at the onset of seizures caused by nerve agents. However, benzodiazepines are less effective at terminating seizures when given 30 min or later after OP exposure or seizure onset likely because of internalization or down-regulation of synaptic, but not extrasynaptic, GABA-A receptors, which can lead to diminished potency and seizure recurrence. PMID:26032507

Bladder outlet obstruction triggers neural plasticity in sensory pathways and contributes to impaired sensitivity in erectile dysfunction.

PubMed

Malykhina, Anna P; Lei, Qi; Chang, Shaohua; Pan, Xiao-Qing; Villamor, Antonio N; Smith, Ariana L; Seftel, Allen D

2013-05-15

Lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) are common problems in aging males worldwide. The objective of this work was to evaluate the effects of bladder neck nerve damage induced by partial bladder outlet obstruction (PBOO) on sensory innervation of the corpus cavernosum (CC) and CC smooth muscle (CCSM) using a rat model of PBOO induced by a partial ligation of the bladder neck. Retrograde labeling technique was used to label dorsal root ganglion (DRG) neurons that innervate the urinary bladder and CC. Contractility and relaxation of the CCSM was studied in vitro, and expression of nitric oxide synthase (NOS) was evaluated by Western blotting. Concentration of the sensory neuropeptides substance P (SP) and calcitonin gene-related peptide was measured by ELISA. Partial obstruction of the bladder neck caused a significant hypertrophy of the urinary bladders (2.5-fold increase at 2 wk). Analysis of L6-S2 DRG sections determined that sensory ganglia received input from both the urinary bladder and CC with 5-7% of all neurons double labeled from both organs. The contractile responses of CC muscle strips to KCl and phenylephrine were decreased after PBOO, followed by a reduced relaxation response to nitroprusside. A significant decrease in neuronal NOS expression, but not in endothelial NOS or protein kinase G (PKG-1), was detected in the CCSM of the obstructed animals. Additionally, PBOO caused some impairment to sensory nerves as evidenced by a fivefold downregulation of SP in the CC (P ≤ 0.001). Our results provide evidence that PBOO leads to the impairment of bladder neck afferent innervation followed by a decrease in CCSM relaxation, downregulation of nNOS expression, and reduced content of sensory neuropeptides in the CC smooth muscle. These results suggest that nerve damage in PBOO may contribute to LUTS-ED comorbidity and trigger secondary changes in the contraction/relaxation mechanisms of CCSM.

Renal denervation by intravascular ultrasound: Preliminary in vivo study

NASA Astrophysics Data System (ADS)

Sinelnikov, Yegor; McClain, Steve; Zou, Yong; Smith, David; Warnking, Reinhard

2012-10-01

Ultrasound denervation has recently become a subject of intense research in connection with the treatment of complex medical conditions including neurological conditions, development of pain management, reproduction of skin sensation, neuropathic pain and spasticity. The objective of this study is to investigate the use of intravascular ultrasound to produce nerve damage in renal sympathetic nerves without significant injury to the renal artery. This technique may potentially be used to treat various medical conditions, such as hypertension. The study was approved by the Institutional Animal Care and Use Committee. Ultrasound was applied to renal nerves of the swine model for histopathological evaluation. Therapeutic ultrasound energy was delivered circumferentially by an intravascular catheter maneuvered into the renal arteries. Fluoroscopic imaging was conducted pre-and post-ultrasound treatment. Animals were recovered and euthanized up to 30 hours post procedure, followed by necropsy and tissue sample collection. Histopathological examination showed evidence of extensive damage to renal nerves, characterized by nuclear pyknosis, hyalinization of stroma and multifocal hemorrhages, with little or no damage to renal arteries. This study demonstrates the feasibility of intravascular ultrasound as a minimally invasive renal denervation technique. Further studies are necessary to evaluate the long-term safety and efficacy of this technique and its related clinical significance.

The effect of palytoxin on neuromuscular junctions in the anococcygeus muscle of the rat.

PubMed

Amir, I; Harris, J B; Zar, M A

1997-06-01

Palytoxin, a highly toxic natural product isolated from zoanthids of the genus Palythoa, is accumulated by a wide range of fishes and marine invertebrates used as food in the Indo-Pacific. It is responsible for many incidents of human morbidity and mortality. The toxin is a potent smooth muscle spasmogen. The cause of the contraction of smooth muscle is unclear, but recent work strongly suggests that it is primarily initiated by the release of neurotransmitters from the motor innervation of the smooth muscle. We show here that palytoxin caused the swelling of the muscle cells and some internal organelles of the anococcygeus muscle of the rat, but no substantial structural damage to the tissue. Axons and Schwann cells were also swollen but the most dramatic feature was the depletion of synaptic vesicles from putative release sites in the axons. Some axons were physically damaged following exposure to the toxin, but this was relatively uncommon (< 10% of all axons studied). In the majority of axons there was no damage to nerve terminal membranes, but there was damage to mitochondria. The depletion of vesicles involved all types-clear, dense-cored, large and small. Our observations and pharmacological data gathered elsewhere, provide a neuropathological basis for the spasmogenic activity of palytoxin.

Acquired auditory neuropathy spectrum disorder after an attack of chikungunya: case study.

PubMed

Prabhu, Prashanth

2016-01-01

Auditory neuropathy spectrum disorder (ANSD) is a retrocochlear disorder in which the cochlear functioning is normal but the transmission in the auditory neural pathway is affected. The present study reports of a 14-year-old teenager with acquired ANSD after an attack of chikungunya. He reported symptoms of difficulty in understanding speech, tinnitus and vertigo when exposed to loud sounds. The audiological characteristics suggested auditory neuropathy spectrum disorder with raising audiogram configuration. The results of tinnitus evaluation showed low-pitched tinnitus and it was persistent causing significant handicap to him based on self report tinnitus handicap questionnaire results. The results of depression, anxiety and stress scale also suggested symptoms of mild depression and anxiety. Chikungunya virus is suspected to be neurotropic in nature which can damage auditory nerve cells and may have caused ANSD. The result also shows presence of tullio's phenomenon and absence of cervical vestibular evoked myogenic potentials suggesting damage to the vestibular neuronal system. The possible pathophysiology of chikungunya virus causing ANSD and vestibular symptoms needs to be explored further in future studies.

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

PubMed

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.

Association of Electroencephalography (EEG) Power Spectra with Corneal Nerve Fiber Injury in Retinoblastoma Patients.

PubMed

Liu, Jianliang; Sun, Juanjuan; Diao, Yumei; Deng, Aijun

2016-09-04

BACKGROUND In our clinical experience we discovered that EEG band power may be correlated with corneal nerve injury in retinoblastoma patients. This study aimed to investigate biomarkers obtained from electroencephalography (EEG) recordings to reflect corneal nerve injury in retinoblastoma patients. MATERIAL AND METHODS Our study included 20 retinoblastoma patients treated at the Department of Ophthalmology, Affiliated Hospital of Weifang Medical University between 2010 and 2014. Twenty normal individuals were included in the control group. EEG activity was recorded continuously with 32 electrodes using standard EEG electrode placement for detecting EEG power. A cornea confocal microscope was used to examine corneal nerve injury in retinoblastoma patients and normal individuals. Spearman rank correlation analysis was used to analyze the correlation between corneal nerve injury and EEG power changes. The sensitivity and specificity of changed EEG power in diagnosis of corneal nerve injury were also analyzed. RESULTS The predominantly slow EEG oscillations changed gradually into faster waves in retinoblastoma patients. The EEG pattern in retinoblastoma patients was characterized by a distinct increase of delta (P<0.01) and significant decrease of theta power P<0.05). Corneal nerves were damaged in corneas of retinoblastoma patients. Corneal nerve injury was positively correlated with delta EEG spectra power and negatively correlated with theta EEG spectra power. The diagnostic sensitivity and specificity by compounding in the series were 60% and 67%, respectively. CONCLUSIONS Changes in delta and theta of EEG appear to be associated with occurrence of corneal nerve injury. Useful information can be provided for evaluating corneal nerve damage in retinoblastoma patients through analyzing EEG power bands.

Neurological Complications in Thyroid Surgery: A Surgical Point of View on Laryngeal Nerves

PubMed Central

Varaldo, Emanuela; Ansaldo, Gian Luca; Mascherini, Matteo; Cafiero, Ferdinando; Minuto, Michele N.

2014-01-01

The cervical branches of the vagus nerve that are pertinent to endocrine surgery are the superior and the inferior laryngeal nerves: their anatomical course in the neck places them at risk during thyroid surgery. The external branch of the superior laryngeal nerve (EB) is at risk during thyroid surgery because of its close anatomical relationship with the superior thyroid vessels and the superior thyroid pole region. The rate of EB injury (which leads to the paralysis of the cricothyroid muscle) varies from 0 to 58%. The identification of the EB during surgery helps avoiding both an accidental transection and an excessive stretching. When the nerve is not identified, the ligation of superior thyroid artery branches close to the thyroid gland is suggested, as well as the abstention from an indiscriminate use of energy-based devices that might damage it. The inferior laryngeal nerve (RLN) runs in the tracheoesophageal groove toward the larynx, close to the posterior aspect of the thyroid. It is the main motor nerve of the intrinsic laryngeal muscles, and also provides sensory innervation to the larynx. Its injury finally causes the paralysis of the omolateral vocal cord and various sensory alterations: the symptoms range from mild to severe hoarseness, to acute airway obstruction, and swallowing impairment. Permanent lesions of the RNL occur from 0.3 to 7% of cases, according to different factors. The surgeon must be aware of the possible anatomical variations of the nerve, which should be actively searched for and identified. Visual control and gentle dissection of RLN are imperative. The use of intraoperative nerve monitoring has been safely applied but, at the moment, its impact in the incidence of RLN injuries has not been clarified. In conclusion, despite a thorough surgical technique and the use of intraoperative neuromonitoring, the incidence of neurological complications after thyroid surgery cannot be suppressed, but should be maintained in a low range. PMID:25076936

Morphological and functional differences between normal-tension and high-tension glaucoma.

PubMed

Häntzschel, Janek; Terai, Naim; Sorgenfrei, Friederike; Haustein, Michael; Pillunat, Karin; Pillunat, Lutz E

2013-08-01

To compare visual field (VF) and nerve fibre loss in patients with normal-tension (NTG) and high-tension glaucoma (HTG) at an equal level of glaucomatous structural damage of the optic nerve head (ONH). In a retrospective, pair-matched, comparative study, 126 eyes with NTG and 126 eyes with HTG were matched according to the same glaucomatous ONH damage based on rim volume, rim area and disc size measured by the Heidelberg Retina Tomograph (HRT III). Visual field by Humphrey perimetry and nerve fibre layer thickness measured by scanning laser polarimetry (GdxVCC) were compared between both groups. Based on the HRT, NTG and HTG displayed comparable structural damage of the ONH without a statistically significant difference between both groups (mean, NTG/HTG: disc area 2.32/2.32 mm², p =0.342; rim area 1.03/1.00 mm², p = 0.279; rim volume 0.2/0.19 mm³; p = 0.274). Eyes with NTG had significantly less VF damage than eyes with HTG (mean, NTG/HTG: mean deviation (MD) -3.69/-9.77 dB, p = 0.0001; pattern standard deviation (PSD) 4.80/7.17 dB, p = 0.0001). The nerve fibre layer of NTG patients was thicker than that of HTG patients (mean, NTG/HTG: GDx total: 46.9/44.0 μm, p = 0.073; GDx superior: 57.2/49.9 μm, p = 0.0001; GDx inferior: 54.9/49.7 μm, p = 0.001). At an equal level of glaucomatous structural damage of the ONH indicated by cupping, rim area and rim volume, NTG patients seem to have a less affected visual field and a better preserved nerve fibre layer than HTG patients. © 2013 The Authors. Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

Advantages of anterior inferior alveolar nerve block with felypressin-propitocaine over conventional epinephrine-lidocaine: an efficacy and safety study

PubMed Central

Sunada, Katsuhisa

2015-01-01

Background Conventional anesthetic nerve block injections into the mandibular foramen risk causing nerve damage. This study aimed to compare the efficacy and safety of the anterior technique (AT) of inferior alveolar nerve block using felypressin-propitocaine with a conventional nerve block technique (CT) using epinephrine and lidocaine for anesthesia via the mandibular foramen. Methods Forty healthy university students with no recent dental work were recruited as subjects and assigned to two groups: right side CT or right side AT. Anesthesia was evaluated in terms of success rate, duration of action, and injection pain. These parameters were assessed at the first incisor, premolar, and molar, 60 min after injection. Chi-square and unpaired t-tests were used for statistical comparisons, with a P value of < 0.05 designating significance. Results The two nerve block techniques generated comparable success rates for the right mandible, with rates of 65% (CT) and 60% (AT) at both the first molar and premolar, and rates of 60% (CT) and 50% (AT) at the lateral incisor. The duration of anesthesia using the CT was 233 ± 37 min, which was approximately 40 min shorter than using the AT. This difference was statistically significant (P < 0.05). Injection pain using the AT was rated as milder compared with the CT. This difference was also statistically significant (P < 0.05). Conclusions The AT is no less successful than the CT for inducing anesthesia, and has the added benefits of a significantly longer duration of action and significantly less pain. PMID:28879260

Advantages of anterior inferior alveolar nerve block with felypressin-propitocaine over conventional epinephrine-lidocaine: an efficacy and safety study.

PubMed

Shinzaki, Hazuki; Sunada, Katsuhisa

2015-06-01

Conventional anesthetic nerve block injections into the mandibular foramen risk causing nerve damage. This study aimed to compare the efficacy and safety of the anterior technique (AT) of inferior alveolar nerve block using felypressin-propitocaine with a conventional nerve block technique (CT) using epinephrine and lidocaine for anesthesia via the mandibular foramen. Forty healthy university students with no recent dental work were recruited as subjects and assigned to two groups: right side CT or right side AT. Anesthesia was evaluated in terms of success rate, duration of action, and injection pain. These parameters were assessed at the first incisor, premolar, and molar, 60 min after injection. Chi-square and unpaired t-tests were used for statistical comparisons, with a P value of < 0.05 designating significance. The two nerve block techniques generated comparable success rates for the right mandible, with rates of 65% (CT) and 60% (AT) at both the first molar and premolar, and rates of 60% (CT) and 50% (AT) at the lateral incisor. The duration of anesthesia using the CT was 233 ± 37 min, which was approximately 40 min shorter than using the AT. This difference was statistically significant (P < 0.05). Injection pain using the AT was rated as milder compared with the CT. This difference was also statistically significant (P < 0.05). The AT is no less successful than the CT for inducing anesthesia, and has the added benefits of a significantly longer duration of action and significantly less pain.

Tai Chi with mental imagery theory improves soleus H-reflex and nerve conduction velocity in patients with type 2 diabetes.

PubMed

Alsubiheen, Abdulrahman; Petrofsky, Jerrold; Daher, Noha; Lohman, Everett; Balbas, Edward; Lee, Haneul

2017-04-01

Diabetes is a disease that leads to damage to the peripheral nerves which may eventually cause balance instability. The purpose of this study was to determine the effect of 8 weeks of Tai Chi (TC) training combined with mental imagery (MI) on soleus H-reflex and nerve conduction velocity (NCV) of the sural and superficial peroneal nerves in people with diabetes. Quasi-experimental, one group pretest-posttest design. Human Research Laboratory. A series of Yang style of Tai Chi classes with mental imagery, one hour, two sessions per week for 8 weeks was done. The Activities-specific Balance Confidence (ABC) Scale, Functional Reach Test (FRT), and One Leg Standing Test (OLS) were measured as functional data. Hoffman reflex (H-reflex), and sural and superficial peroneal NCV were measured as main outcomes. All functional outcomes measures were significantly improved after the intervention (p<0.01). In the H-reflex, there was a significant increase in amplitude (μV) after completing 8 weeks of TC exercise (p=0.02). In the sural nerve, the velocity (p=0.01), amplitude (p=0.01), and latency (p=0.01) were significantly improved between pre and post-test. In the superficial peroneal nerve, significant improvements were observed in (p=0.02) and latency (p=0.01), but not in amplitude (μV) (p>0.05). Combining TC intervention with MI theory showed an improvement in the H-reflex and NCV tests, which suggests improved balance and walking stability. Copyright © 2017 Elsevier Ltd. All rights reserved.

TFOS DEWS II pain and sensation report

PubMed Central

Belmonte, Carlos; Nichols, Jason J.; Cox, Stephanie M.; Brock, James A.; Begley, Carolyn G.; Bereiter, David A.; Dartt, Darlene A.; Galor, Anat; Hamrah, Pedram; Ivanusic, Jason J.; Jacobs, Deborah S.; McNamara, Nancy A.; Rosenblatt, Mark I.; Stapleton, Fiona; Wolffsohn, James S.

2017-01-01

Pain associated to mechanical and chemical irritation of the eye surface is mediated by trigeminal ganglia mechano- and polymodal nociceptor neurons while cold thermoreceptors detect wetness and reflexly maintain basal tear production and blinking rate. These neurons project into two regions of the trigeminal brain stem nuclear complex: ViVc, activated by changes in the moisture of the ocular surface and VcC1, mediating sensory-discriminative aspects of ocular pain and reflex blinking. ViVc ocular neurons project to brain regions that control lacrimation and spontaneous blinking and to the sensory thalamus. Secretion of the main lacrimal gland is regulated dominantly by autonomic parasympathetic nerves, reflexly activated by eye surface sensory nerves. These also evoke goblet cell secretion through unidentified efferent fibers. Neural pathways involved in the regulation of Meibonian gland secretion or mucins release have not been identified. In dry eye disease, reduced tear secretion leads to inflammation and peripheral nerve damage. Inflammation causes sensitization of polymodal and mechano-nociceptor nerve endings and an abnormal increase in cold thermoreceptor activity, altogether evoking dryness sensations and pain. Long-term inflammation and nerve injury alter gene expression of ion channels and receptors at terminals and cell bodies of trigeminal ganglion and brainstem neurons, changing their excitability, connectivity and impulse firing. Perpetuation of molecular, structural and functional disturbances in ocular sensory pathways ultimately leads to dysestesias and neuropathic pain referred to the eye surface. Pain can be assessed with a variety of questionaires while the status of corneal nerves is evaluated with esthesiometry and with in vivo confocal microscopy. PMID:28736339

Long-term consequences of topical dexamethasone treatment during acute corneal HSV-1 infection on the immune system

PubMed Central

Chucair-Elliott, Ana J.; Carr, Meghan M.; Carr, Daniel J. J.

2017-01-01

Herpes simplex virus type 1 (HSV-1) is a leading cause of neurotrophic keratitis (NTK). NTK is characterized by decreased corneal sensation from damage to the corneal sensory fibers. We have reported on the regression of corneal nerves and their function during acute HSV-1 infection. That nerve loss is followed by an aberrant process of nerve regeneration during the latent phase of infection that lacks functional recovery. We recently showed the elicited immune response in the infected cornea, and not viral replication itself, is part of the mechanism responsible for the nerve degeneration process after infection. Specifically, we showed infected corneas topically treated with dexamethasone (DEX) significantly retained both structure and sensitivity of the corneal nerve network in comparison to mice treated with control eye drops, consistent with decreased levels of proinflammatory cytokines and reduced influx of macrophages and CD8+ T cells into the cornea. This study was undertaken to analyze the long-term effect of such a localized, immunosuppressive paradigm (DEX drops on the cornea surface during the first 8 d of HSV-1 infection) on the immune system and on corneal pathology. We found the profound immunosuppressive effect of DEX on lymphoid tissue was sustained in surviving mice for up to 30 d postinfection (p.i.). DEX treatment had prolonged effects, preserving corneal innervation and its function and blunting neovascularization, as analyzed at 30 d p.i. Our data support previously reported observations of an association between the persistent presence of inflammatory components in the latently infected cornea and structural and functional nerve defects in NTK. PMID:28115476

Greater occipital nerve neuralgia caused by pathological arterial contact: treatment by surgical decompression.

PubMed

Cornely, Christiane; Fischer, Marius; Ingianni, Giulio; Isenmann, Stefan

2011-04-01

Occipital nerve neuralgia is a rare cause of severe headache, and may be difficult to treat. We report the case of a patient with occipital nerve neuralgia caused by pathological contact of the nerve with the occipital artery. The pain was refractory to medical treatment. Surgical decompression yielded complete remission. © 2010 American Headache Society.

A patient with bilateral facial palsy associated with hypertension and chickenpox: learning points.

PubMed

Al-Abadi, Eslam; Milford, David V; Smith, Martin

2010-11-26

Bilateral facial nerve paralysis is an uncommon presentation and even more so in children. There are reports of different causes of bilateral facial nerve palsy. It is well-established that hypertension and chickenpox causes unilateral facial paralysis and the importance of checking the blood pressure in children with facial nerve paralysis cannot be stressed enough. The authors report a boy with bilateral facial nerve paralysis in association with hypertension and having recently recovered from chickenpox. The authors review aspects of bilateral facial nerve paralysis as well as hypertension and chickenpox causing facial nerve paralysis.

A patient with bilateral facial palsy associated with hypertension and chickenpox: learning points

PubMed Central

Al-Abadi, Eslam; Milford, David V; Smith, Martin

2010-01-01

Bilateral facial nerve paralysis is an uncommon presentation and even more so in children. There are reports of different causes of bilateral facial nerve palsy. It is well-established that hypertension and chickenpox causes unilateral facial paralysis and the importance of checking the blood pressure in children with facial nerve paralysis cannot be stressed enough. The authors report a boy with bilateral facial nerve paralysis in association with hypertension and having recently recovered from chickenpox. The authors review aspects of bilateral facial nerve paralysis as well as hypertension and chickenpox causing facial nerve paralysis. PMID:22797481

[Analysis of the changes in the causes of blindness and significant vision loss among children and young adults born between 1974 and 2004].

PubMed

Seroczyńska, Małgorzata; Grałek, Mirosława; Kanigowska, Krystyna

2007-01-01

Visual impairment develops serious medical, psychological, social and economical problems. Thus, of most importance is improvement in prophylaxis, early diagnosis and treatment. THE AIM of this paper is to define the reasons of blindness and significant loss of vision in children and youths in Poland, and changes in them among children and youths under the age of 24, born between 1974-2004, with classification by age. Included in the study were the records of 2,518 children and youths under the age of 24, associates of the Polski Zwiazek Niewidomych (PZN, Polish Association of the Blind); these were analyzed for the prevalence of each cause of vision loss. There were two groups. The first group were files of 1,504 students and pupils in the institutions for blind and visually impaired children, and the archives of PZN, describing the members who joined it between year 1974 and 1998. The second, comparative group, was based on files of 1,014 children and students, who joined PZN between year 1999 and 2004. Each group was also analysed within different age groups. The most important causes of visual impairment are: optic nerve atrophy, retinopathy of prematurity (ROP), high myopia, congenital cataract and retinal degradations. Changes in them between 1998-2004 introduce a percentage growth of optic nerve atrophy from 21.66% to 25.41% and decrement in vision degrading stages of ROP from 14.14% to 10.71%, in development disorders from 8.09% to 7.10%. There is an alarming growth in congenital toxoplasmosis percentage, from 1.06% to 2.39%, and of congenital cataract, from 3.02% to 4.47%. High myopia among the visually impaired remains at the same level. There is a big growth in the percentage of heavy (bilateral) injuries, which cause significant vision loss. Less often, the cause of serious vision damage are uveitis, secondary glaucoma and toxocariasis. The study conducted between 1998-2004 revealed changes in the causes of blindness and significantly vision loss in children and youths under the age of 24, as compared to a similar study conducted between 1974-1998. There is constant increase of the optic nerve atrophy as a cause of vision loss, and decrease among vision impairments caused by vision damaging stages of ROP. Cataract and congenital abnormalities are more frequent among youngest children. Cortical blindness, formerly rarely diagnosed, is becoming a significant factor. The results of our study, describing the changes in blindness and significant vision loss factors, should provide a proper rationale for developing a strategy for control of visual impairment in children and youths.

An unusual case of isolated sixth cranial nerve palsy in leprosy.

PubMed

Vaishampayan, Sanjeev; Borde, Priyanka

2012-08-15

Cranial nerve involvement is not common in leprosy. The fifth and seventh cranial nerves are the most commonly affected in leprosy. Herein we present a patient with Hansen disease (BL) with type I reaction who developed isolated involvement of the sixth cranial nerve leading to lateral rectus muscle palsy. He responded to timely anti-reactional therapy and it produced a good response. Careful observation of patients with lepra reaction is needed to avoid damage to important organs.

[Minamata disease: a neuropathological viewpoint].

PubMed

Eto, Komyo

2006-01-01

Minamata disease (methylmercury poisoning) was first officially discovered around Minamata Bay in the Kumamoto Prefecture on May 1st, 1956. This year, a commemoration marking fifty years since this discovery of Minamata disease will be held in Minamata City. Over the years, new facts have gradually surfaced, especially after 1995, with the resolution of the political problems surrounding Minamata disease. For example, it was recently reported that large amounts of methylmercury were generated by the chemical processes of the Chisso acetaldehyde plant and later dumped directly into Minamata Bay. This report revealed the August 1951 switch from using manganese dioxide to ferric sulfide as a reaction promoter to maintain the activity of the Hg catalyst. As a result of this switch, the amount of methylmercury generated in the process rapidly increased. Thus, the true cause of the acute onset of Minamata disease in patients with a high-dose contamination of methylmercury was made clear. The severe contamination by methylmercury continued until 1968, when the plant finally stopped discharging its waste water into Minamata Bay. In 1996, the National Institute for Minamata Disease started an experimental study of methylmercury poisoning using the common marmoset. Results from this study showed that the lesions characteristic of the central nervous system in cases of acute methylmercury poisoning were promoted by brain edema, while those of the peripheral nerves were caused by axonal degeneration. Peripheral nerves were regenerated in two animals after two and a half years. Lesions characteristic of Minamata disease are systematically found throughout the nervous system. These lesions are found in the calcarine areas of occipital lobes, the pre- and post-central lobes, and the temporal transverse gyri. Milder and more diffuse lesions are also found in the cerebrum, where secondary degeneration of the central parts of white matter and internal sagittal stratum are due to primary damage of neurons. Purkinje and granular cells decrease in number in the cerebellum depending on the dose of methylmercury and the duration of methylmercury exposure. In the spinal cord, there is no primary change, but secondary degeneration is found on pyramidal tracts due to damage of the motor neurons of the precentral cortices. Additionally, secondary degeneration of Goll's tract is seen due to the primary degeneration of sensory nerve fibers including ganglion cells, sciatic nerves, and sural nerves. The experiments on the methylmercury-treated common marmosets provided every feature of pathological change found in the nervous system in human autopsy cases, depending on the dose of methylmercury.

Mechanism of demyelination after HSV type I intraocular injection in rabbits.

PubMed

Narang, H K

1980-02-01

Intraocular injection of herpes simplex virus (HSV) type I into the vitreous body of 18-day-old rabbits induced, on the 7th day post-inoculation, neurological signs with marked head jerking and atazia. Examination of semi-serial 1-micrometers thick sections of the whole lengths of right and left optic nerves and chiasma of 4--64 days post-inoculated rabbits revealed a small lesion, restricted to the medial side, which had extended 2--3 mm, during the first 4 days, along the optic nerve. Ahead of the developing lesion marked chromatin changes of neuroglial cells were noticed followed by cuffing of blood vessels, infiltration by macrophages, demyelination and remyelination. The present study indicated that demyelination occurred following the infection of the myelinating cells. It appeared that virus did not become latent and many cells survived the viral attack. Repeated episodies of viral activity caused further damage while repair did not keep pace.

Management of asymptomatic gene carriers of transthyretin familial amyloid polyneuropathy

PubMed Central

Barroso, Fabio; González‐Duarte, Alejandra; Conceição, Isabel; Obici, Laura; Keohane, Denis; Amass, Leslie

2016-01-01

ABSTRACT Transthyretin familial amyloid polyneuropathy (TTR‐FAP) is a rare, severe, and irreversible, adult‐onset, hereditary disorder caused by autosomal‐dominant mutations in the TTR gene that increase the intrinsic propensity of transthyretin protein to misfold and deposit systemically as insoluble amyloid fibrils in nerve tissues, the heart, and other organs. TTR‐FAP is characterized by relentless, progressively debilitating polyneuropathy, and leads to death, on average, within 10 years of symptom onset without treatment. With increased availability of disease‐modifying treatment options for a wider spectrum of patients with TTR‐FAP, timely detection of the disease may offer substantial clinical benefits. This review discusses mutation‐specific predictive genetic testing in first‐degree relatives of index patients diagnosed with TTR‐FAP and the structured clinical follow‐up of asymptomatic gene carriers for prompt diagnosis and early therapeutic intervention before accumulation of substantial damage. Muscle Nerve 54: 353–360, 2016 PMID:27273296

The role of oxidative stress in organophosphate and nerve agent toxicity

PubMed Central

Pearson, Jennifer N.; Patel, Manisha

2016-01-01

Organophosphate nerve agents exert their toxicity through inhibition of acetylcholinesterase. The excessive stimulation of cholinergic receptors rapidly causes neuronal damage, seizures, death, and long-term neurological impairment in those that survive. Owing to the lethality of organophosphorus agents and the growing risk they pose, medical interventions that prevent organophosphate toxicity and the delayed injury response are much needed. Studies have shown that oxidative stress occurs in models of subacute, acute, and chronic exposure to organophosphate agents. Key findings of these studies include alterations in mitochondrial function and increased free radical–mediated injury, such as lipid peroxidation. This review focuses on the role of reactive oxygen species in organophosphate neurotoxicity and its dependence on seizure activity. Understanding the sources, mechanisms, and pathological consequences of organophosphate-induced oxidative stress can lead to the development of rational therapies for treating toxic exposures. PMID:27371936

Composite fibrous glaucoma drainage implant

NASA Astrophysics Data System (ADS)

Klapstova, A.; Horakova, J.; Shynkarenko, A.; Lukas, D.

2017-10-01

Glaucoma is a frequent reason of loss vision. It is usually caused by increased intraocular pressure leading to damage of optic nerve head. This work deals with the development of fibrous structure suitable for glaucoma drainage implants (GDI). Commercially produced metallic glaucoma implants are very effective in lowering intraocular pressure. However, these implants may cause adverse events such as damage to adjacent tissue, fibrosis, hypotony or many others [1]. The aim of this study is to reduce undesirable properties of currently produced drains and improve their properties by creating of the composite fibrous drain for achieve a normal intraocular pressure. Two types of electrospinning technologies were used for the production of very small tubular implants. First type was focused for production of outer part of tubular drain and the second type of electrospinning method made the inner part of shape follows the connections of both parts. Complete implant had a special properties suitable for drainage of fluid. Morphological parameters, liquid transport tests and in-vitro cell adhesion tests were detected.

Characterization of toxin-producing cyanobacteria by using an oligonucleotide probe containing a tandemly repeated heptamer.

PubMed Central

Rouhiainen, L; Sivonen, K; Buikema, W J; Haselkorn, R

1995-01-01

Cyanobacteria produce toxins that kill animals. The two main classes of cyanobacterial toxins are cyclic peptides that cause liver damage and alkaloids that block nerve transmission. Many toxin-producing strains from Finnish lakes were brought into axenic culture, and their toxins were characterized. Restriction fragment length polymorphism analysis, probing with a short tandemly repeated DNA sequence found at many locations in the chromosome of Anabaena sp. strain PCC 7120, distinguishes hepatotoxic Anabaena isolates from neurotoxin-producing strains and from Nostoc spp. PMID:7592362

[Temperature-dependent changes in the microcirculation of the dental pulp].

PubMed

Raab, W H; Müller, H

1989-07-01

Laser Doppler flowmetry was used to study the changes in the blood flow within the dental pulp as a reaction to thermal stimuli between 17 degrees C and 57 degree C. Temperatures below 31 degrees C resulted in a reduction, temperatures above 43 degrees C in an increase in blood flow. Temperatures higher than 49 degrees C caused irreversible damage to the pulp's microcirculation. Experimental nerve blocks showed that the reactive increase is linked to the afferent rather than the sympathetic innervation of the tooth pulp.

[What was found in deformities of leprosy patients from the view-point of orthopedics?].

PubMed

Obara, Akiko

2003-08-01

No more deformities which are the cause of social stigma by early detection and chemotherapy! Let patients learn how to avoid getting deformed to keep normal ADL & QOL. Fight against the nerve damage and stop the progressive deformities by organizing the team approach. Instead of intense efforts of taking care by well organized team work, deformities are resulted inevitably in some cases. Let their deformities be out of the way of their keeping normal community lives without any prejudice, respecting their human rights and dignity.

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

PubMed

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.

[Precise application of Traditional Chinese Medicine in minimally-invasive techniques].

PubMed

Dong, Fu-Hui

2018-06-25

The miminally-invasive techniques of traditional Chinese medicine(TCM) uses different types of acupuncture needles to treat diseased locations with special techniques. These techniques include different methods of insertion and closed incision (press cutting, sliding cutting, scrape cutting, etc.). This needling technique is based on the traditional Chinese medicine theories of Pi Bu (cutaneous), Jing Jin (sinew), Jing Luo (meridian), Wu Ti (five body structure components) and Zang Fu (organ system). Commonly used needles include: needle Dao , needle with edge, Pi needle, Shui needle, Ren needle, Gou needle, Chang Yuan needle, Bo needle and so on. The principle of this minimally-invasive technique of TCM is to achieve the greatest healing benefit with the least amount of anatomical and physiological intervention. This will result in the highest standard of health care with the lowest rehabilitative need and burden of care. In the past 20 years, through the collaborative research of several hundred hospitals across China, we systemically reviewed the best minimally invasive technique of TCM and the first line treatments for selective conditions. In 2013, the Department of Medical Affairs of the State Administration of Traditional Chinese Medicine created "Traditional Chinese Medicine Technical Manual"(General Version) and released it nationwide, its contents include: (1)Minimally invasive scar tissue release. ¹Suitable for Bi and pain syndromes of neck, shoulder, waist, buttocks and extremities. ²Degeneration causes local hypertrophy and inflammation, creating local tissue adhesion. ³There are two kind incision methods-press cutting and slide cutting. (2)Minimally invasive fascial tension release. ¹Suitable for localized fascial tension caused by trauma, overuse, or wind-cold-dampness, leading to compensatory hyperplasia. ²Long term high-stress stimulation to local fascia creates compensatory hyperplasia, Ashi points, and tissue texture changes (cords, nodules, masses). ³According to the different structural features of the needles, there are two incision methods: penetrating from the outside to the inside and pulling from inside to outside. (3)Minimally invasive decompression technique. ¹Suitable for internal pressure changes within organ cavities caused by trauma, degeneration, inflammation, such as compartment syndrome, bone marrow edema, increased intraluminal pressure in the bone marrow. ²According to the different tissues, it is categorized into soft tissue decompression, and bone decompression. (4)Minimally invasive orthopedic surgery. Applicable to some postural, developmental deformity correction, mainly through the dynamic balance method and/or static balance method. (5)Minimally invasive dissection. Suitable for fractures, tendons injury caused by deep soft tissue adhesion. (6)Minimally invasive separation. ¹Suitable for cutaneous, sinew regions, superficial adhesions due to lesions, and local post-operative incision adhesions. ²According to the structure of the needle tip, the methods are divided into sharp separation and blunt dissection. (7)Minimally invasive sustained pressure technique. ¹Suitable for neuromuscular dysfunction which causes JING (spasm) syndrome and WEI (atrophy) syndrome. ²The needle is applied with sustained pressure, without penetrating select tissue surface. This includes: nerve root sustained pressure technique; peripheral nerve sustained pressure technique; muscle sustained pressure technique; fascial contact procedure; cutaneous sustained pressure technique.(8)Minimally invasive insertion technique. ¹Suitable for systemic regulation to treat disease. ²Different organs are connected to different layers of tissue. Therefore, to treat specific conditions, specific tissues must be targeted. ³For example, back Shu points are used to treat vertigo from cervical spine issues, and spinal degeneration associated digestion issue. ⁴The internal organs can be regulated by the pathways that runs along the different layers of tissue. The types of stimulation include: meridian acupoint stimulation; cutaneous stimulation; fascia stimulation; mucle stimulation; periosteum stimulation. The clinical application of these techniques has enriched the drug-free therapies of traditional Chinese medicine and achieved excellent outcomes, but at the same time it also raises an important question. How can we apply these minimally invasive techniques to clinical practice so it can be safe and effective? In addition, how can practitioners, individually and further develop their understanding of this minimally invasive technique progressive manner? We make the following recommendations. (1)Clear diagnosis and precise application. Any approach has specific indications and choosing the correct technique comes from a comprehensive understanding of its advantages and disadvantages. Moreover, the accurate application of the technique depends the expertise of the practitioner. Through systematic review and clinical observation, we formulated the First Line Treatment, the Second Line Treatment, and the Third Line Treatment for specific conditions. Using the information gathered from research, practitioners can decide on which point is appropriate to use based on the stage of disease progression. For example, common conditions like the nerve ending tension pain(i.e. cutaneous nerve entrapment syndrome) is caused by stress concentration. There are two types of treatment for this condition: ¹Change in the response to stress state (i.e.non-invasive approach such as manual therapy and physiotherapy). ²Change in state of surrounding environment (i.e. invasive approach such as Pi Needle). Before tissue texture changes to pain point, cord, nodules, the former approach is effective. Once tissue texture changes, the latter approach is First Line Treatment. (2)Systematic training and disease progression training. The minimally invasive techniques of traditional Chinese medicine can treat many kinds of disease. To ensure its safety, organization, progressive development, practitioners are trained systematically and manage their treatment approach through disease hierarchy. Moreover, this technique should be conducted according to its technical difficulty, operating conditions, and expertise of the practitioner. The application of minimally invasive techniques of traditional Chinese medicine does not depend on the hospitals' administration system or the regulatory college of medical professionals. The minimally invasive techniques of TCM should be taught from easy to difficult, simple to complicated, and requires gradual progression by the practitioners. Eventually, the minimally invasive techniques of TCM's diagnostic and treatment protocol can be created. These protocols are currently available for reference: ¹Forming diagnosis and differential diagnosis for the conditions below requires expert diagnostic and application skills: cerebral palsy; cervical vertigo; cervical headache; cervical precordial pain; other spine-related diseases. ²The requirements for the diagnosis and differential diagnosis of such techniques are relatively high, and special training is required for the practitioner who performs this technique. The conditions below uses minimally invasive orthopedic surgery and dissection: scar contracture deformity; congenital developmental malformations; cervical Bi -syndrome; shoulder pain syndrome; knee Bi -syndrome; low back pain; cervical spondylosis; lumbar disc herniation; avascular necrosis of the femoral head; ankylosing spondylitis. ³There are no special requirements for the diagnosis and differential diagnosis of such techniques, and special training is required for the practitioner who performs this technique. The technical content is mainly decompression and scar tissue release. a)Muscle strain diseases: levator scapulae, splenius capitis, splenius cervicis, supraspinatus, infraspinatus, teres minor, teres major, serratus posterior superior, serratus posterior inferior, piriformis, gluteus maximus, gluteus medius, and gluteus minimus, erector spinae. b)Joint degenerative disorders: frozen shoulder, tennis elbow, tenosynovitis, knee osteoarthritis, and plantar fascitis. c) JING-JIN PI-BU pain syndrome (cutaneous nerve entrapment syndrome): occipital great nerve entrapment syndrome, occipital small nerve entrapment syndrome, great auricular nerve entrapment syndrome, suprascapular nerve entrapment syndrome, transverse cutaneous nerve of neck entrapment syndrome. (3)People-centred practice. The most attractive feature of the minimally invasive techniques of TCM is that they do not rely on expensive medical equipment and operating conditions. The key to applying this technique is the practitioners' technique, skill, and expertise. The necessary conditions required to successfully apply this technique is ¹practitioner understands disease progression and diagnosis; ²practitioners' skill in applying technique. We require patient-centered approach, which uses evidence based approach as the focus. We aim to seek the truth from facts, to understand the comprehensive picture, to include pertinent details, to be observant, to be goal oriented, from one to another, from outside to inside, from top to the bottom, compare right from left, through active movement and passive movements and weight-bearing movements, and assisted passive movements to determine instantaneous centre to diagnose stress concentration points. The operating technique is based on the response of patient's tissues to this technique. We must pay attention to diagnosis through palpation: layers, structure, texture, deformity, dislocation, movement characteristic, rhythmic changes. To achieve SHOU MO XIN HUI WU WEI : position, quantify, quantity, timing, and pattern. Accurate grasp of timeliness and dose efficiency. Can distinguish between local or systemic effects of treatment. Through comprehensive judgment of hands feeling, acupuncture needle feeling, and inspiration, to achieve the precious treatment requirements as indicated by the "Huangdi Neijing·Suwen" : "Puncture the bone without damaging tendons, and puncture tendons without damaging muscles, puncture the muscle without damaging pulse, puncture pulse without damaging skin, puncture skin without damaging muscle. Puncture muscle without damage tendons, puncture tendons without damaging bone... Puncture bone without damaging tendons and it means the needle passes through the tendons and arrives at the bone and work on the bone. Puncture tendons without damaging muscles, and it means the needle passes through the muscles and arrives close to the tendon. Puncture the muscle without damaging pulse and it means the needle passes the pulse and does not touch the muscle. Puncture pulse without damaging skin and it means, the needle passes through the skin without penetrating pulse. Puncture skin without damaging muscle and it means, the disease is in the skin and the needles insert into skin but does not damage muscle. Puncture muscle without damage tendons, and it means, the needle passes through the muscle and arrive on the tendon. Puncture tendons without damaging bone." Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

Sciatic Nerve Intrafascicular Lidocaine Injection-induced Peripheral Neuropathic Pain: Alleviation by Systemic Minocycline Administration.

PubMed

Cheng, Kuang-I; Wang, Hung-Chen; Wu, Yi-Chia; Tseng, Kuang-Yi; Chuang, Yi-Ta; Chou, Chao-Wen; Chen, Ping-Luen; Chang, Lin-Li; Lai, Chung-Sheng

2016-06-01

Peripheral nerve block guidance with a nerve stimulator or echo may not prevent intrafascicular injury. This study investigated whether intrafascicular lidocaine induces peripheral neuropathic pain and whether this pain can be alleviated by minocycline administration. A total of 168 male Sprague-Dawley rats were included. In experiment 1, 2% lidocaine (0.1 mL) was injected into the left sciatic nerve. Hindpaw responses to thermal and mechanical stimuli, and sodium channel and activating transcription factor (ATF-3) expression in dorsal root ganglion (DRG) and glial cells in the spinal dorsal horn (SDH), were measured on days 4, 7, 14, 21, and 28. On the basis of the results in experiment 1, rats in experiment 2 were divided into sham, extraneural, intrafascicular, peri-injury minocycline, and postinjury minocycline groups. Behavioral responses, macrophage recruitment, expression changes of myelin basic protein and Schwann cells in the sciatic nerve, dysregulated expression of ATF-3 in the DRG, and activated glial cells in L5 SDH were assessed on days 7 and 14. Intrafascicular lidocaine induced mechanical allodynia, downregulated Nav1.8, increased ATF-3 expression in the DRG, and activated glial cells in the SDH. Increased expression of macrophages, Schwann cells, and myelin basic protein was found in the sciatic nerve. Minocycline attenuated intrafascicular lidocaine-induced neuropathic pain and nerve damage significantly. Peri-injury minocycline was better than postinjury minocycline administration in alleviating mechanical behaviors, mitigating macrophage recruitment into the sciatic nerve, and suppressing activated microglial cells in the spinal cord. Systemic minocycline administration alleviates intrafascicular lidocaine injection-induced peripheral nerve damage.

Histopathology of cryoballoon ablation-induced phrenic nerve injury.

PubMed

Andrade, Jason G; Dubuc, Marc; Ferreira, Jose; Guerra, Peter G; Landry, Evelyn; Coulombe, Nicolas; Rivard, Lena; Macle, Laurent; Thibault, Bernard; Talajic, Mario; Roy, Denis; Khairy, Paul

2014-02-01

Hemi-diaphragmatic paralysis is the most common complication associated with cryoballoon ablation for atrial fibrillation, yet the histopathology of phrenic nerve injury has not been well described. A preclinical randomized study was conducted to characterize the histopathology of phrenic nerve injury induced by cryoballoon ablation and assess the potential for electromyographic (EMG) monitoring to limit phrenic nerve damage. Thirty-two dogs underwent cryoballoon ablation of the right superior pulmonary vein with the objective of inducing phrenic nerve injury. Animals were randomized 1:1 to standard monitoring (i.e., interruption of ablation upon reduction in diaphragmatic motion) versus EMG guidance (i.e., cessation of ablation upon a 30% reduction in the diaphragmatic compound motor action potential [CMAP] amplitude). The acute procedural endpoint was achieved in all dogs. Phrenic nerve injury was characterized by Wallerian degeneration, with subperineural injury to large myelinated axons and evidence of axonal regeneration. The degree of phrenic nerve injury paralleled the reduction in CMAP amplitude (P = 0.007). Animals randomized to EMG guidance had a lower incidence of acute hemi-diaphragmatic paralysis (50% vs 100%; P = 0.001), persistent paralysis at 30 days (21% vs 75%; multivariate odds ratio 0.12, 95% confidence interval [0.02, 0.69], P = 0.017), and a lesser severity of histologic injury (P = 0.001). Mature pulmonary vein ablation lesion characteristics, including circumferentiality and transmurality, were similar in both groups. Phrenic nerve injury induced by cryoballoon ablation is axonal in nature and characterized by Wallerian degeneration, with potential for recovery. An EMG-guided approach is superior to standard monitoring in limiting phrenic nerve damage. © 2013 Wiley Periodicals, Inc.

Preservation of Facial Nerve Function Repaired by Using Fibrin Glue-Coated Collagen Fleece for a Totally Transected Facial Nerve during Vestibular Schwannoma Surgery

PubMed Central

Choi, Kyung-Sik; Kim, Min-Su; Jang, Sung-Ho

2014-01-01

Recently, the increasing rates of facial nerve preservation after vestibular schwannoma (VS) surgery have been achieved. However, the management of a partially or completely damaged facial nerve remains an important issue. The authors report a patient who was had a good recovery after a facial nerve reconstruction using fibrin glue-coated collagen fleece for a totally transected facial nerve during VS surgery. And, we verifed the anatomical preservation and functional outcome of the facial nerve with postoperative diffusion tensor (DT) imaging facial nerve tractography, electroneurography (ENoG) and House-Brackmann (HB) grade. DT imaging tractography at the 3rd postoperative day revealed preservation of facial nerve. And facial nerve degeneration ratio was 94.1% at 7th postoperative day ENoG. At postoperative 3 months and 1 year follow-up examination with DT imaging facial nerve tractography and ENoG, good results for facial nerve function were observed. PMID:25024825

Phrenic nerve protection via packing of gauze into the pericardial space during ablation of cristal atrial tachycardia in a child.

PubMed

Takahashi, Kazuhiro; Fuchigami, Tai; Nabeshima, Taisuke; Sashinami, Arata; Nakayashiro, Mami

2016-03-01

The success of catheter ablation of focal atrial tachycardia is limited by possible collateral damage to the phrenic nerve. Protection of the phrenic nerve is required. Here we present a case of a 9-year-old girl having a history of an unsuccessful catheter ablation of a focal atrial tachycardia near the crista terminalis (because of proximity of the phrenic nerve) who underwent a successful ablation by means of a novel technique for phrenic nerve protection: packing of gauze into the pericardial space. This method is a viable approach for patients with a failed endocardial ablation due to the proximity of the phrenic nerve.

Non tuberculous mycobacterial lesion of the parotid gland and facial skin in a 4year old girl: A proposed treatment strategy.

PubMed

Berkovic, Juraj; Vanchiere, John A; Gungor, Anil

2016-01-01

We report a case of a parotid-facial caseating granulomatous infection caused by atypical mycobacteria (Mycobacterium avium) in an immuno-competent child. The size and depth of the lesion and its proximity to the facial nerve present a challenge for a purely surgical treatment strategy. An alternative treatment strategy is developed to avoid severe disfigurement. Atypical mycobacterial infection of the parotid region in a 5 year old girl: timeline and definition of a planned combined treatment strategy with antibiotics and surgical excision. Cervicofacial infections caused by non-tuberculous mycobacteria (NTM) may present surgical challenges due to the size and depth of the lesion and its proximity to the facial nerve and major vascular structures. Even minor scars are highly visible and poorly tolerated. Close clinical monitoring combined with judicious treatment strategies is necessary for successful treatment and good cosmesis. Recent literature provides insufficient guidance in formulating the best treatment strategy for the individual patient. Comparisons of antibiotic therapy with variations of surgical excision are abundant but poorly formulated. Our case presented with a lesion involving skin, superficial and deep lobe of the parotid gland. Lesion was in immediate proximity to the distribution of the facial nerve through the parotid gland. The risk of surgical damage to the facial nerve in the acute phase of the inflammation and the required extent of skin excision were significant. We decided to start treatment with combination antimycobacterial antibiotics in close cooperation with the pediatric infectious disease specialists. We observed and documented the regress and executed a delayed surgical excision when the lesion was reduced to skin only. In our opinion this was the best treatment strategy that helped us avoid extensive dissection in the vicinity of the facial nerve as well as a parotidectomy. Excision of the involved skin with the deep portion was performed 6.5 months after initial diagnosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Nanofibrous scaffolds for the guidance of stem cell-derived neurons for auditory nerve regeneration.

PubMed

Hackelberg, Sandra; Tuck, Samuel J; He, Long; Rastogi, Arjun; White, Christina; Liu, Liqian; Prieskorn, Diane M; Miller, Ryan J; Chan, Che; Loomis, Benjamin R; Corey, Joseph M; Miller, Josef M; Duncan, R Keith

2017-01-01

Impairment of spiral ganglion neurons (SGNs) of the auditory nerve is a major cause for hearing loss occurring independently or in addition to sensory hair cell damage. Unfortunately, mammalian SGNs lack the potential for autonomous regeneration. Stem cell based therapy is a promising approach for auditory nerve regeneration, but proper integration of exogenous cells into the auditory circuit remains a fundamental challenge. Here, we present novel nanofibrous scaffolds designed to guide the integration of human stem cell-derived neurons in the internal auditory meatus (IAM), the foramen allowing passage of the spiral ganglion to the auditory brainstem. Human embryonic stem cells (hESC) were differentiated into neural precursor cells (NPCs) and seeded onto aligned nanofiber mats. The NPCs terminally differentiated into glutamatergic neurons with high efficiency, and neurite projections aligned with nanofibers in vitro. Scaffolds were assembled by seeding GFP-labeled NPCs on nanofibers integrated in a polymer sheath. Biocompatibility and functionality of the NPC-seeded scaffolds were evaluated in vivo in deafened guinea pigs (Cavia porcellus). To this end, we established an ouabain-based deafening procedure that depleted an average 72% of SGNs from apex to base of the cochleae and caused profound hearing loss. Further, we developed a surgical procedure to implant seeded scaffolds directly into the guinea pig IAM. No evidence of an inflammatory response was observed, but post-surgery tissue repair appeared to be facilitated by infiltrating Schwann cells. While NPC survival was found to be poor, both subjects implanted with NPC-seeded and cell-free control scaffolds showed partial recovery of electrically-evoked auditory brainstem thresholds. Thus, while future studies must address cell survival, nanofibrous scaffolds pose a promising strategy for auditory nerve regeneration.

[Possibility of cauda equina nerve root damage from lumbar punctures performed with 25-gauge Quincke and Whitacre needles].

PubMed

Reina, M A; López, A; Villanueva, M C; De Andrés, J A; Martín, S

2005-05-01

To assess the possibility of puncturing nerve roots in the cauda equina with spinal needles with different point designs and to quantify the number of axons affected. We performed in vitro punctures of human nerve roots taken from 3 fresh cadavers. Twenty punctures were performed with 25-gauge Whitacre needles and 40 with 25-gauge Quincke needles; half the Quincke needle punctures were carried out with the point perpendicular to the root and the other half with the point parallel to it. The samples were studied by optical and scanning electron microscopy. The possibility of finding the needle orifece inserted inside the nerve was assessed. On a photographic montage, we counted the number of axons during a hypothetical nerve puncture. Nerve roots used in this study were between 1 and 2.3 mm thick, allowing the needle to penetrate the root in the 52 samples studied. The needle orifice was never fully located inside the nerve in any of the samples. The numbers of myelinized axons affected during nerve punctures 0.2 mm deep were 95, 154, and 81 for Whitacre needles, Quincke needles with the point held perpendicular, or the same needle type held parallel, respectively. During punctures 0.5 mm deep, 472, 602, and 279 were affected for each puncture group, respectively. The differences in all cases were statistically significant. It is possible to achieve intraneural puncture with 25-gauge needles. However, full intraneural placement of the orifice of the needle is unlikely. In case of nerve trauma, the damage could be greater if puncture is carried out with a Quincke needle with the point inserted perpendicular to the nerve root.

Retinal ganglion cell damage in an experimental rodent model of blast-mediated traumatic brain injury.

PubMed

Mohan, Kabhilan; Kecova, Helga; Hernandez-Merino, Elena; Kardon, Randy H; Harper, Matthew M

2013-05-15

To evaluate retina and optic nerve damage following experimental blast injury. Healthy adult mice were exposed to an overpressure blast wave using a custom-built blast chamber. The effects of blast exposure on retina and optic nerve function and structure were evaluated using the pattern electroretinogram (pERG), spectral domain optical coherence tomography (OCT), and the chromatic pupil light reflex. Assessment of the pupil response to light demonstrated decreased maximum pupil constriction diameter in blast-injured mice using red light or blue light stimuli 24 hours after injury compared with baseline in the eye exposed to direct blast injury. A decrease in the pupil light reflex was not observed chronically following blast exposure. We observed a biphasic pERG decrease with the acute injury recovering by 24 hours postblast and the chronic injury appearing at 4 months postblast injury. Furthermore, at 3 months following injury, a significant decrease in the retinal nerve fiber layer was observed using OCT compared with controls. Histologic analysis of the retina and optic nerve revealed punctate regions of reduced cellularity in the ganglion cell layer and damage to optic nerves. Additionally, a significant upregulation of proteins associated with oxidative stress was observed acutely following blast exposure compared with control mice. Our study demonstrates that decrements in retinal ganglion cell responses can be detected after blast injury using noninvasive functional and structural tests. These objective responses may serve as surrogate tests for higher CNS functions following traumatic brain injury that are difficult to quantify.

A novel chondroitin sulfate hydrogel for nerve repair

NASA Astrophysics Data System (ADS)

Conovaloff, Aaron William

Brachial plexus injuries affect numerous patients every year, with very debilitating results. The majority of these cases are very severe, and involve damage to the nerve roots. To date, repair strategies for these injuries address only gross tissue damage, but do not supply cells with adequate regeneration signals. As a result, functional recovery is often severely lacking. Therefore, a chondroitin sulfate hydrogel that delivers neurotrophic signals to damaged neurons is proposed as a scaffold to support nerve root regeneration. Capillary electrophoresis studies revealed that chondroitin sulfate can physically bind with a variety of neurotrophic factors, and cultures of chick dorsal root ganglia demonstrated robust neurite outgrowth in chondroitin sulfate hydrogels. Outgrowth in chondroitin sulfate gels was greater than that observed in control gels of hyaluronic acid. Furthermore, the chondroitin sulfate hydrogel's binding activity with nerve growth factor could be enhanced by incorporation of a synthetic bioactive peptide, as revealed by fluorescence recovery after photobleaching. This enhanced binding was observed only in chondroitin sulfate gels, and not in hyaluronic acid control gels. This enhanced binding activity resulted in enhanced dorsal root ganglion neurite outgrowth in chondroitin sulfate gels. Finally, the growth of regenerating dorsal root ganglia in these gels was imaged using label-free coherent anti-Stokes scattering microscopy. This technique generated detailed, high-quality images of live dorsal root ganglion neurites, which were comparable to fixed, F-actin-stained samples. Taken together, these results demonstrate the viability of this chondroitin sulfate hydrogel to serve as an effective implantable scaffold to aid in nerve root regeneration.

Regenerating reptile retinas: a comparative approach to restoring retinal ganglion cell function.

PubMed

Williams, D L

2017-02-01

Transection or damage to the mammalian optic nerve generally results in loss of retinal ganglion cells by apoptosis. This cell death is seen less in fish or amphibians where retinal ganglion cell survival and axon regeneration leads to recovery of sight. Reptiles lie somewhere in the middle of this spectrum of nerve regeneration, and different species have been reported to have a significant variation in their retinal ganglion cell regenerative capacity. The ornate dragon lizard Ctenophoris ornatus exhibits a profound capacity for regeneration, whereas the Tenerife wall lizard Gallotia galloti has a more variable response to optic nerve damage. Some individuals regain visual activity such as the pupillomotor responses, whereas in others axons fail to regenerate sufficiently. Even in Ctenophoris, although the retinal ganglion cell axons regenerate adequately enough to synapse in the tectum, they do not make long-term topographic connections allowing recovery of complex visually motivated behaviour. The question then centres on where these intraspecies differences originate. Is it variation in the innate ability of retinal ganglion cells from different species to regenerate with functional validity? Or is it variances between different species in the substrate within which the nerves regenerate, the extracellular environment of the damaged nerve or the supporting cells surrounding the regenerating axons? Investigations of retinal ganglion cell regeneration between different species of lower vertebrates in vivo may shed light on these questions. Or perhaps more interesting are in vitro studies comparing axon regeneration of retinal ganglion cells from various species placed on differing substrates.

Facial nerve palsy associated with a cystic lesion of the temporal bone.

PubMed

Kim, Na Hyun; Shin, Seung-Ho

2014-03-01

Facial nerve palsy results in the loss of facial expression and is most commonly caused by a benign, self-limiting inflammatory condition known as Bell palsy. However, there are other conditions that may cause facial paralysis, such as neoplastic conditions of the facial nerve, traumatic nerve injury, and temporal bone lesions. We present a case of facial nerve palsy concurrent with a benign cystic lesion of the temporal bone, adjacent to the tympanic segment of the facial nerve. The patient's symptoms subsided after facial nerve decompression via a transmastoid approach.

Perineurial Glial Plasticity and the Role of TGF-β in the Development of the Blood-Nerve Barrier.

PubMed

Morris, Angela D; Lewis, Gwendolyn M; Kucenas, Sarah

2017-05-03

Precisely orchestrated interactions between spinal motor axons and their ensheathing glia are vital for forming and maintaining functional spinal motor nerves. Following perturbations to peripheral myelinating glial cells, centrally derived oligodendrocyte progenitor cells (OPCs) ectopically exit the spinal cord and myelinate peripheral nerves in myelin with CNS characteristics. However, whether remaining peripheral ensheathing glia, such as perineurial glia, properly encase the motor nerve despite this change in glial cell and myelin composition, remains unknown. Using zebrafish mutants in which OPCs migrate out of the spinal cord and myelinate peripheral motor axons, we assayed perineurial glial development, maturation, and response to injury. Surprisingly, in the presence of OPCs, perineurial glia exited the CNS normally. However, aspects of their development, response to injury, and function were altered compared with wildtype larvae. In an effort to better understand the plasticity of perineurial glia in response to myelin perturbations, we identified transforming growth factor-β1 as a partial mediator of perineurial glial development. Together, these results demonstrate the incredible plasticity of perineurial glia in the presence of myelin perturbations. SIGNIFICANCE STATEMENT Peripheral neuropathies can result from damage or dysregulation of the insulating myelin sheath surrounding spinal motor axons, causing pain, inefficient nerve conduction, and the ectopic migration of oligodendrocyte progenitor cells (OPCs), the resident myelinating glial cell of the CNS, into the periphery. How perineurial glia, the ensheathing cells that form the protective blood-nerve barrier, are impacted by this myelin composition change is unknown. Here, we report that certain aspects of perineurial glial development and injury responses are mostly unaffected in the presence of ectopic OPCs. However, perineurial glial function is disrupted along nerves containing centrally derived myelin, demonstrating that, although perineurial glial cells display plasticity despite myelin perturbations, the blood-nerve barrier is compromised in the presence of ectopic OPCs. Copyright © 2017 the authors 0270-6474/17/374790-18$15.00/0.

The Use of Quantitative SPECT/CT Imaging to Assess Residual Limb Health

DTIC Science & Technology

2017-10-01

loss in 2020.4 BACKGROUND The integrity of the vasculature, nerves, and soft tissue within the extremities is of high importance, as an impairment or...formation, and vascular abnormalities .6 Therefore, effective diagnosis can be critical in directing the medical treatment of patients. Standard noninva...and identify damage to their nor- mal fasicular pattern, nerve swelling or thickening, loss of nerve bundle integrity , and development of neuromas

The safety profile of a retrospective Accessory Postero-Lateral hind foot portal: the risk of sural nerve damage during visualisation of the Achilles tendon insertion.

PubMed

Carmont, M R; Stroud, R; Bjorndalen, H; Crowther, J; Ribbans, W J; Griffin, D

2012-06-01

The Accessory Postero-Lateral (AccPL) portal has recently been described to improve the visualisation for the endoscopic debridement of Haglund's tubercle. The safety of using this portal has been considered previously for posterior ankle arthroscopy. We performed a study to determine the proximity of the AccPL portal to the sural nerve. We compared the distances between AccPL and PL portals to the sural nerve in 17 cadaveric specimens. The AccPL portal was significantly closer (mean 12.0mm, range 6-19 mm, SD=3.64) to the sural nerve than the PL portal (mean 14.1mm, range 11-18 mm, SD=2.34) (t(16)=-2.34, p=0.03). In two cases the sural nerve was in contact with the clip but on close inspection, the nerve had not been damaged in any of the specimens. We conclude that the AccPL portal is a safe method to allow visualisation during endoscopic debridement of the Achilles tendon insertion. We also recommend that the portal is used for visualisation rather than instrumentation. Copyright © 2011 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Acute optic nerve sheath fenestration in humans using the free electron laser (FEL): a case report

NASA Astrophysics Data System (ADS)

Joos, Karen M.; Mawn, Louise A.; Shen, Jin-Hui; Jansen, E. Duco; Casagrande, Vivien A.

2002-06-01

Our previous studies using rabbits and monkeys showed that the Amide II wavelength (6.45 micrometers ) produced by the FEL could efficiently produce an optic nerve sheath fenestration with minimal damage. In order to determine if the technology safely could be applied to human surgery, we used 2 blind human eyes during enucleation to compare the results of producing fenestrations with the FEL or a scissors. FDA and Vanderbilt IRB approvals, and individual patient consents were obtained. The FEL energy was transmitted to a human operating room. After disinsertion of the medial rectus muscle, an optic nerve sheath fenestration (2 mm diameter) was made with either the FEL (6.45 micrometers , 325 micrometers spot size, 30 Hz, 3 mJ) through a hollow waveguide surgical probe or with a scissors. The enucleation was then completed. The optic nerve was dissected from the globe and fixed. Specimens were examined histologically. Dural incisions were effective with both methods. FEL energy at 6.45 micrometers can be transmitted to an operating room and delivered to human ocular tissue through a hollow waveguide surgical probe. This FEL wavelength can produce an optic nerve sheath fenestration without acute direct damage to the nerve in this case report.

Preoperative computed tomography diagnosis of non-recurrent laryngeal nerve in patients with esophageal carcinoma.

PubMed

Niu, Zhong-Xi; Zhang, Hang; Chen, Long-Qi; Shi, Hui; Peng, Jun; Su, Li-Wei; Li, Wei; Xiao, Bo; He, Shu; Yue, Hong-Xu

2017-01-01

The non-recurrent laryngeal nerve (NRLN) is a rare but potentially serious anomaly that is commonly associated with the aberrant right subclavian artery (ARSA). It is easy to damage during surgical resection of esophageal cancer, leading to severe complications. Preoperative enhanced thoracic computed tomography (CT) scans of 2697 patients with esophageal carcinoma treated in our hospital between January 2010 and December 2013 were examined. We classified the positional relationship between the right subclavian artery and the membranous wall of the trachea into two types and used this method to predicate NRLN by identifying ARSA. Twenty-six patients (0.96%) were identified with ARSA, all of which were cases of NRLN by CT. NRLN was identified during surgery in the 26 patients, and a normal right recurrent laryngeal nerve was observed in 2671 patients. The ARSA was detected on the dorsal side of the membranous wall of the trachea in all 26 NRLN cases, while it was detected on the ventral side in all 2671 recurrent laryngeal nerve cases. Enhanced CT scanning is a reliable method for predicting NRLN by identifying ARSA. Preoperative recognition of this nerve anomaly allows surgeons to avoid damaging the nerve and abnormal vessels during esophagectomy. © 2016 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Suprascapular Nerve Entrapment Caused by Protrusion of an Intraosseous Ganglion of the Glenoid into the Spinoglenoid Notch: A Rare Cause of Posterior Shoulder Pain

PubMed Central

Terabayashi, Nobuo; Nishimoto, Yutaka; Akiyama, Haruhiko

2017-01-01

We describe a case of suprascapular nerve entrapment caused by protrusion of an intraosseous ganglion of the glenoid into the spinoglenoid notch. A 47-year-old man with left shoulder pain developed an intraosseous cyst in the left glenoid, which came into contact with the suprascapular nerve. The area at which the patient experienced spontaneous shoulder pain was innervated by the suprascapular nerve, and 1% xylocaine injection into the spinoglenoid notch under ultrasonographic guidance relieved the pain. Therefore, we concluded that the protrusion of an intraosseous cyst of the glenoid into the spinoglenoid notch was a cause of the pain, and performed curettage. Consequently, the shoulder pain was resolved promptly without suprascapular nerve complications, and the cyst was histologically diagnosed as an intraosseous ganglion. This case demonstrated that the intraosseous ganglion of the glenoid was a benign lesion but could be a cause of suprascapular nerve entrapment syndrome. Curettage is a useful treatment option for a ganglion inside bone and very close to the suprascapular nerve. PMID:28620557

Comparison of Whole Body SOD1 Knockout with Muscle-Specific SOD1 Knockout Mice Reveals a Role for Nerve Redox Signaling in Regulation of Degenerative Pathways in Skeletal Muscle.

PubMed

Sakellariou, Giorgos K; McDonagh, Brian; Porter, Helen; Giakoumaki, Ifigeneia I; Earl, Kate E; Nye, Gareth A; Vasilaki, Aphrodite; Brooks, Susan V; Richardson, Arlan; Van Remmen, Holly; McArdle, Anne; Jackson, Malcolm J

2018-02-01

Lack of Cu,Zn-superoxide dismutase (CuZnSOD) in homozygous knockout mice (Sod1 -/- ) leads to accelerated age-related muscle loss and weakness, but specific deletion of CuZnSOD in skeletal muscle (mSod1KO mice) or neurons (nSod1KO mice) resulted in only mild muscle functional deficits and failed to recapitulate the loss of mass and function observed in Sod1 -/- mice. To dissect any underlying cross-talk between motor neurons and skeletal muscle in the degeneration in Sod1 -/- mice, we characterized neuromuscular changes in the Sod1 -/- model compared with mSod1KO mice and examined degenerative molecular mechanisms and pathways in peripheral nerve and skeletal muscle. In contrast to mSod1KO mice, myofiber atrophy in Sod1 -/- mice was associated with increased muscle oxidative damage, neuromuscular junction degeneration, denervation, nerve demyelination, and upregulation of proteins involved in maintenance of myelin sheaths. Proteomic analyses confirmed increased proteasomal activity and adaptive stress responses in muscle of Sod1 -/- mice that were absent in mSod1KO mice. Peripheral nerve from neither Sod1 -/- nor mSod1KO mice showed increased oxidative damage or molecular responses to increased oxidation compared with wild type mice. Differential cysteine (Cys) labeling revealed a specific redox shift in the catalytic Cys residue of peroxiredoxin 6 (Cys47) in the peripheral nerve from Sod1 -/- mice. Innovation and Conclusion: These findings demonstrate that neuromuscular integrity, redox mechanisms, and pathways are differentially altered in nerve and muscle of Sod1 -/- and mSod1KO mice. Results support the concept that impaired redox signaling, rather than oxidative damage, in peripheral nerve plays a key role in muscle loss in Sod1 -/- mice and potentially sarcopenia during aging. Antioxid. Redox Signal. 28, 275-295.

Post-traumatic Unilateral Avulsion of the Abducens Nerve with Damage to Cranial Nerves VII and VIII: Case Report.

PubMed

Yamasaki, Fumiyuki; Akiyama, Yuji; Tsumura, Ryu; Kolakshyapati, Manish; Adhikari, Rupendra Bahadur; Takayasu, Takeshi; Nosaka, Ryo; Kurisu, Kaoru

2016-07-01

Traumatic injuries of the abducens nerve as a consequence of facial and/or head trauma occur with or without associated cervical or skull base fracture. This is the first report on unilateral avulsion of the abducens nerve in a 29-year-old man with severe right facial trauma. In addition, he exhibited mild left facial palsy, and moderate left hearing disturbance. Magnetic resonance imaging (MRI) using fast imaging employing steady-state acquisition (FIESTA) revealed avulsion of left sixth cranial nerve. We recommend thin-slice MR examination in patients with abducens palsy after severe facial and/or head trauma.

Glaucoma –state of the art and perspectives on treatment

PubMed Central

Wójcik-Gryciuk, Anna; Skup, Małgorzata; Waleszczyk, Wioletta J.

2015-01-01

Glaucoma is a chronic optic neuropathy characterized by progressive damage to the optic nerve, death of retinal ganglion cells and ultimately visual field loss. It is one of the leading causes of irreversible loss of vision worldwide. The most important trigger of glaucomatous damage is elevated eye pressure, and the current standard approach in glaucoma therapy is reduction of intraocular pressure (IOP). However, despite the use of effective medications or surgical treatment leading to lowering of IOP, progression of glaucomatous changes and loss of vision among patients with glaucoma is common. Therefore, it is critical to prevent vision loss through additional treatment. To implement such treatment(s), it is imperative to identify pathophysiological changes in glaucoma and develop therapeutic methods taking into account neuroprotection. Currently, there is no method of neuroprotection with long-term proven effectiveness in the treatment of glaucoma. Among the most promising molecules shown to protect the retina and optic nerve are neurotrophic factors. Thus, the current focus is on the development of safe and non-invasive methods for the long-term elevation of the intraocular level of neurotrophins through advanced gene therapy and topical eye treatment and on the search for selective agonists of neurotrophin receptors affording more efficient neuroprotection. PMID:26684267

Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures

NASA Astrophysics Data System (ADS)

Tran, H.; Grimm, J.; Wang, B.; Smith, M. A.; Gogola, A.; Nelson, S.; Tyler-Kabara, E.; Schuman, J.; Wollstein, G.; Sigal, I. A.

2017-02-01

Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.

Posterior Branches of Lumbar Spinal Nerves - Part I: Anatomy and Functional Importance.

PubMed

Kozera, Katarzyna; Ciszek, Bogdan

2016-01-01

The aim of this paper is to compare anatomic descriptions of posterior branches of the lumbar spinal nerves and, on this basis, present the location of these structures. The majority of anatomy textbooks do not describe these nerves in detail, which may be attributable to the fact that for many years they were regarded as structures of minor clinical importance. The state of knowledge on these nerves has changed within the last 30 years. Attention has been turned to their function and importance for both diagnostic practice and therapy of lower back pain. Summarising the available literature, we may conclude that the medial and lateral branches separate at the junction of the facet joint and the distal upper edge of the transverse process; that the size, course and area supplied differ between the lateral and the medial branch; and that facet joints receive multisegmental innervation. It has been demonstrated that medial branches are smaller than the respective lateral branches and they have a more constant course. Medial branches supply the area from the midline to the facet joint line, while lateral branches innervate tissues lateral to the facet joint. The literature indicates difficulties with determining specific anatomic landmarks relative to which the lateral branch and the distal medial branch can be precisely located. Irritation of sensory fibres within posterior branches of the lumbar spinal nerves may be caused by pathology of facet joints, deformity of the spine or abnormalities due to overloading or injury. The anatomic location and course of posterior branches of spinal nerves should be borne in mind to prevent damaging them during low-invasive analgesic procedures.

Noise Stress Induces an Epidermal Growth Factor Receptor/Xeroderma Pigmentosum-A Response in the Auditory Nerve.

PubMed

Guthrie, O'neil W

2017-03-01

In response to toxic stressors, cancer cells defend themselves by mobilizing one or more epidermal growth factor receptor (EGFR) cascades that employ xeroderma pigmentosum-A (XPA) to repair damaged genes. Recent experiments discovered that neurons within the auditory nerve exhibit basal levels of EGFR+XPA co-expression. This finding implied that auditory neurons in particular or neurons in general have the capacity to mobilize an EGFR+XPA defense. Therefore, the current study tested the hypothesis that noise stress would alter the expression pattern of EGFR/XPA within the auditory nerve. Design-based stereology was used to quantify the proportion of neurons that expressed EGFR, XPA, and EGFR+XPA with and without noise stress. The results revealed an intricate neuronal response that is suggestive of alterations to both co-expression and individual expression of EGFR and XPA. In both the apical and middle cochlear coils, the noise stress depleted EGFR+XPA expression. Furthermore, there was a reduction in the proportion of neurons that expressed XPA-alone in the middle coils. However, the noise stress caused a significant increase in the proportion of neurons that expressed EGFR-alone in the middle coils. The basal cochlear coils failed to mobilize a significant response to the noise stress. These results suggest that EGFR and XPA might be part of the molecular defense repertoire of the auditory nerve.

Noise Stress Induces an Epidermal Growth Factor Receptor/Xeroderma Pigmentosum–A Response in the Auditory Nerve

PubMed Central

Guthrie, O’neil W.

2017-01-01

In response to toxic stressors, cancer cells defend themselves by mobilizing one or more epidermal growth factor receptor (EGFR) cascades that employ xeroderma pigmentosum–A (XPA) to repair damaged genes. Recent experiments discovered that neurons within the auditory nerve exhibit basal levels of EGFR+XPA co-expression. This finding implied that auditory neurons in particular or neurons in general have the capacity to mobilize an EGFR+XPA defense. Therefore, the current study tested the hypothesis that noise stress would alter the expression pattern of EGFR/XPA within the auditory nerve. Design-based stereology was used to quantify the proportion of neurons that expressed EGFR, XPA, and EGFR+XPA with and without noise stress. The results revealed an intricate neuronal response that is suggestive of alterations to both co-expression and individual expression of EGFR and XPA. In both the apical and middle cochlear coils, the noise stress depleted EGFR+XPA expression. Furthermore, there was a reduction in the proportion of neurons that expressed XPA-alone in the middle coils. However, the noise stress caused a significant increase in the proportion of neurons that expressed EGFR-alone in the middle coils. The basal cochlear coils failed to mobilize a significant response to the noise stress. These results suggest that EGFR and XPA might be part of the molecular defense repertoire of the auditory nerve. PMID:28056182

Relapsing Painful Ophthalmoplegic Neuropathy: No longer a "Migraine," but Still a Headache.

PubMed

Smith, Stacy V; Schuster, Nathaniel M

2018-06-14

Recurrent painful ophthalmoplegic neuropathy (RPON), formerly known as ophthalmoplegic migraine, is an uncommon disorder with repeated episodes of ocular cranial nerve neuropathy associated with ipsilateral headache. This review discusses the clinical presentation, current understanding of the pathophysiology, key differential diagnoses, and evaluation and treatment of RPON. The literature is limited due to the rarity of the disorder. Recent case reports and series continue to suggest the age of first attack is most often during childhood or adolescence as well as a female predominance. Multiple recent case reports and series demonstrate focal enhancement of the affected cranial nerve, as the nerve root exits the brainstem. This finding contributed to the current classification of the disorder as a neuropathy, with the present understanding that it is due to a relapsing-remitting inflammatory or demyelinating process. The link to migraine remains a cause of disagreement in the literature. RPON is a complex disorder with features of inflammatory neuropathy and an unclear association with migraine. Regardless, the overall prognosis is good for individual episodes, but permanent nerve damage may accumulate with repeated attacks. A better understanding of the pathogenesis is needed to clarify whether it truly represents a single disorder and to guide its treatment. Until that time, a combined approach with acute and preventive therapies can mitigate acute symptoms as well as attempt to limit recurrence of this disabling syndrome.

Benjamin Franklin and his glass armonica: from music as therapeutic to pathological.

PubMed

Finger, Stanley; Zeitler, William

2015-01-01

In 1762, Benjamin Franklin, then in London, wrote a letter to a colleague in Italy describing his latest invention, a musical instrument he called the "armonica," which was based on how rubbing a wet finger on the rims of wine glasses could produce musical tones. In contrast to earlier sets of wine glasses that could be tapped or rubbed, Franklin put a set of glass bowls differing in size on a horizontal rod turned by a food treadle, thus freeing both hands for touching the rotating glasses and allowing musicians to play more than two glasses at a time, as well as eliminating the nuisance of water tuning. Franklin played his instrument for pleasure, to manipulate the "passions" (emotions) and to treat melancholia. Nevertheless, late in his lifetime some individuals began to view glass armonica music differently, alleging it could cause nerve damage and mental problems. Here, we look at how Franklin used his glass armonica to manipulate the passions and examine what he must have thought about it supposedly causing health problems. We present Franklin as an empiricist, whose focus was more on results than theories; as an astute student of human behavior understanding the power of charms and other "nonsense"; and as a man of medicine living in an era when much was being attributed to the nerves, even though next to nothing was really known about the underlying nerve force. © 2015 Elsevier B.V. All rights reserved.

The course of the superficial peroneal nerve in relation to the ankle position: anatomical study with ankle arthroscopic implications

PubMed Central

Golanó, Pau; Sierevelt, Inger N.; van Dijk, C. Niek

2010-01-01

Despite the fact that the superficial peroneal nerve is the only nerve in the human body that can be made visible; iatrogenic damage to this nerve is the most frequently reported complication in anterior ankle arthroscopy. One of the methods to visualize the nerve is combined ankle plantar flexion and inversion. In the majority of cases, the superficial peroneal nerve can be made visible. The portals for anterior ankle arthroscopy are however created with the ankle in the neutral or slightly dorsiflexed position and not in combined plantar flexion and inversion. The purpose of this study was to undertake an anatomical study to the course of the superficial peroneal nerve in different positions of the foot and ankle. We hypothesize that the anatomical localization of the superficial peroneal nerve changes with different foot and ankle positions. In ten fresh frozen ankle specimens, a window, only affecting the skin, was made at the level of the anterolateral portal for anterior ankle arthroscopy in order to directly visualize the superficial peroneal nerve, or if divided, its terminal branches. Nerve movement was assessed from combined 10° plantar flexion and inversion to 5° dorsiflexion, standardized by the Telos stress device. Also for the 4th toe flexion, flexion of all the toes and for skin tensioning possible nerve movement was determined. The mean superficial peroneal nerve movement was 2.4 mm to the lateral side when the ankle was moved from 10° plantar flexion and inversion to the neutral ankle position and 3.6 mm to the lateral side from 10° plantar flexion and inversion to 5° dorsiflexion. Both displacements were significant (P < 0.01). The nerve consistently moves lateral when the ankle is manoeuvred from combined plantar flexion and inversion to the neutral or dorsiflexed position. If visible, it is therefore advised to create the anterolateral portal medial from the preoperative marking, in order to prevent iatrogenic damage to the superficial peroneal nerve. PMID:20224993

Investigation of Laser Induced Breakdown Spectroscopy (LIBS) for the Differentiation of Nerve and Gland Tissue—A Possible Application for a Laser Surgery Feedback Control Mechanism

NASA Astrophysics Data System (ADS)

Mehari, F.; Rohde, M.; Knipfer, C.; Kanawade, R.; Klämpfl, F.; W., Adler; Oetter, N.; Stelzle, F.; Schmidt, M.

2016-06-01

Laser surgery provides clean, fast and accurate modeling of tissue. However, the inability to determine what kind of tissue is being ablated at the bottom of the cut may lead to the iatrogenic damage of structures that were meant to be preserved. In this context, nerve preservation is one of the key challenges in any surgical procedure. One example is the treatment of parotid gland pathologies, where the facial nerve (N. VII) and its main branches run through and fan out inside the glands parenchyma. A feedback system that automatically stops the ablation to prevent nerve-tissue damage could greatly increase the applicability and safety of surgical laser systems. In the present study, Laser Induced Breakdown Spectroscopy (LIBS) is used to differentiate between nerve and gland tissue of an ex-vivo pig animal model. The LIBS results obtained in this preliminary experiment suggest that the measured spectra, containing atomic and molecular emissions, can be used to differentiate between the two tissue types. The measurements and differentiation were performed in open air and under normal stray light conditions.

Comparison of retinal nerve fiber layer thickness in vivo and axonal transport after chronic intraocular pressure elevation in young versus older rats.

PubMed

Abbott, Carla J; Choe, Tiffany E; Burgoyne, Claude F; Cull, Grant; Wang, Lin; Fortune, Brad

2014-01-01

To compare in young and old rats longitudinal measurements of retinal nerve fiber layer thickness (RNFLT) and axonal transport 3-weeks after chronic IOP elevation. IOP was elevated unilaterally in 2- and 9.5-month-old Brown-Norway rats by intracameral injections of magnetic microbeads. RNFLT was measured by spectral domain optical coherence tomography. Anterograde axonal transport was assessed from confocal scanning laser ophthalmolscopy of superior colliculi (SC) after bilateral intravitreal injections of cholera toxin-B-488. Optic nerve sections were graded for damage. Mean IOP was elevated in both groups (young 37, old 38 mmHg, p = 0.95). RNFL in young rats exhibited 10% thickening at 1-week (50.9±8.1 µm, p<0.05) vs. baseline (46.4±2.4 µm), then 7% thinning at 2-weeks (43.0±7.2 µm, p>0.05) and 3-weeks (43.5±4.4 µm, p>0.05), representing 20% loss of dynamic range. RNFLT in old rats showed no significant change at 1-week (44.9±4.1 µm) vs. baseline (49.2±5.3 µm), but progression to 22% thinning at 2-weeks (38.0±3.7 µm, p<0.01) and 3-weeks (40.0±6.6 µm, p<0.05), representing 59% loss of dynamic range. Relative SC fluorescence intensity was reduced in both groups (p<0.001), representing 77-80% loss of dynamic range and a severe transport deficit. Optic nerves showed 75-95% damage (p<0.001). There was greater RNFL thinning in old rats (p<0.05), despite equivalent IOP insult, transport deficit and nerve damage between age groups (all p>0.05). Chronic IOP elevation resulted in severely disrupted axonal transport and optic nerve axon damage in all rats, associated with mild RNFL loss in young rats but a moderate RNFL loss in old rats despite the similar IOP insult. Hence, the glaucomatous injury response within the RNFL depends on age.

HCV RNA Genomic sequences and HCV-E2 glycoprotein in sural nerve biopsies from HCV-infected patients with peripheral neuropathy.

PubMed

Russi, S; Sansonno, D; Monaco, S; Mariotto, S; Ferrari, S; Pavone, F; Lauletta, G; Dammacco, F

2018-06-01

Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications. We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively. Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients. These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms. © 2017 British Neuropathological Society.

Training at non-damaging intensities facilitates recovery from muscle atrophy.

PubMed

Itoh, Yuta; Murakami, Taro; Mori, Tomohiro; Agata, Nobuhide; Kimura, Nahoko; Inoue-Miyazu, Masumi; Hayakawa, Kimihide; Hirano, Takayuki; Sokabe, Masahiro; Kawakami, Keisuke

2017-02-01

Resistance training promotes recovery from muscle atrophy, but optimum training programs have not been established. We aimed to determine the optimum training intensity for muscle atrophy. Mice recovering from atrophied muscles after 2 weeks of tail suspension underwent repeated isometric training with varying joint torques 50 times per day. Muscle recovery assessed by maximal isometric contraction and myofiber cross-sectional areas (CSAs) were facilitated at 40% and 60% maximum contraction strength (MC), but at not at 10% and 90% MC. At 60% and 90% MC, damaged and contained smaller diameter fibers were observed. Activation of myogenic satellite cells and a marked increase in myonuclei were observed at 40%, 60%, and 90% MC. The increases in myofiber CSAs were likely caused by increased myonuclei formed through fusion of resistance-induced myofibers with myogenic satellite cells. These data indicate that resistance training without muscle damage facilitates efficient recovery from atrophy. Muscle Nerve 55: 243-253, 2017. © 2016 Wiley Periodicals, Inc.

Characterization of Frequency-Dependent Responses of the Vascular System to Repetitive Vibration

PubMed Central

Krajnak, Kristine; Miller, G. Roger; Waugh, Stacey; Johnson, Claud; Kashon, Michael L.

2015-01-01

Objective Occupational exposure to hand-transmitted vibration can result in damage to nerves and sensory loss. The goal of this study was to assess the frequency-dependent effects of repeated bouts of vibration on sensory nerve function and associated changes in nerves. Methods The tails of rats were exposed to vibration at 62.5, 125, or 250 Hz (constant acceleration of 49m/s2) for 10 days. The effects on sensory nerve function, nerve morphology, and transcript expression in ventral tail nerves were measured. Results Vibration at all frequencies had effects on nerve function and physiology. However, the effects tended to be more prominent with exposure at 250 Hz. Conclusion Exposure to vibration has detrimental effects on sensory nerve function and physiology. However, many of these changes are more prominent at 250-Hz exposure than at lower frequencies. PMID:22785326

Characteristics of pellet injuries to the orbit.

PubMed

Kükner, A Sahap; Yilmaz, Turgut; Celebi, Serdal; Karslioğlu, Safak; Alagöz, Gürsoy; Serin, Didem; Acar, M Akif; Ozveren, M Faik

2009-01-01

To investigate the features of orbital injuries by pellets fired from the front. Retrospective, 4 cases of pellet injuries. Five orbits of 4 patients who sustained pellet injuries received from the front were reviewed retrospectively. The course of injury and results were assessed. Radiological examinations were reviewed. The patients were evaluated between December 1996 and June 2004. Five orbits of 4 patients sustained injuries caused by pellets fired from an anterior direction. The globe in the injured orbit was intact in 2 cases. Severe loss of vision was also present in these 2 globes due to optic nerve involvement. Final visual acuity was down to no light perception in 4 eyes and limited to light perception in 1 eye. The prognosis of orbital pellet injuries is, unfortunately, poor. A pellet passing through the floor of the orbit often causes double perforation of the globe and, once in the orbital aperture, it travels towards the apex as a result of the conical shape of the orbit and lodges in the optic canal or its entrance, severely damaging the optic nerve. Surgery or other treatments are usually unsuccessful. Even if the globe is intact, vision is usually severely impaired. Copyright 2009 S. Karger AG, Basel.

Auditory and non-auditory effects of noise on health

PubMed Central

Basner, Mathias; Babisch, Wolfgang; Davis, Adrian; Brink, Mark; Clark, Charlotte; Janssen, Sabine; Stansfeld, Stephen

2014-01-01

Noise is pervasive in everyday life and can cause both auditory and non-auditory health effects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular mechanisms involved in noise-induced hair-cell and nerve damage has substantially increased, and preventive and therapeutic drugs will probably become available within 10 years. Evidence of the non-auditory effects of environmental noise exposure on public health is growing. Observational and experimental studies have shown that noise exposure leads to annoyance, disturbs sleep and causes daytime sleepiness, affects patient outcomes and staff performance in hospitals, increases the occurrence of hypertension and cardiovascular disease, and impairs cognitive performance in schoolchildren. In this Review, we stress the importance of adequate noise prevention and mitigation strategies for public health. PMID:24183105

Retinal Ganglion Cell Damage in an Experimental Rodent Model of Blast-Mediated Traumatic Brain Injury

PubMed Central

Mohan, Kabhilan; Kecova, Helga; Hernandez-Merino, Elena; Kardon, Randy H.; Harper, Matthew M.

2013-01-01

Purpose. To evaluate retina and optic nerve damage following experimental blast injury. Methods. Healthy adult mice were exposed to an overpressure blast wave using a custom-built blast chamber. The effects of blast exposure on retina and optic nerve function and structure were evaluated using the pattern electroretinogram (pERG), spectral domain optical coherence tomography (OCT), and the chromatic pupil light reflex. Results. Assessment of the pupil response to light demonstrated decreased maximum pupil constriction diameter in blast-injured mice using red light or blue light stimuli 24 hours after injury compared with baseline in the eye exposed to direct blast injury. A decrease in the pupil light reflex was not observed chronically following blast exposure. We observed a biphasic pERG decrease with the acute injury recovering by 24 hours postblast and the chronic injury appearing at 4 months postblast injury. Furthermore, at 3 months following injury, a significant decrease in the retinal nerve fiber layer was observed using OCT compared with controls. Histologic analysis of the retina and optic nerve revealed punctate regions of reduced cellularity in the ganglion cell layer and damage to optic nerves. Additionally, a significant upregulation of proteins associated with oxidative stress was observed acutely following blast exposure compared with control mice. Conclusions. Our study demonstrates that decrements in retinal ganglion cell responses can be detected after blast injury using noninvasive functional and structural tests. These objective responses may serve as surrogate tests for higher CNS functions following traumatic brain injury that are difficult to quantify. PMID:23620426

Supralethal poisoning by any of the classical nerve agents is effectively counteracted by procyclidine regimens in rats.

PubMed

Myhrer, Trond; Mariussen, Espen; Enger, Siri; Aas, Pål

2015-09-01

A treatment regimen consisting of HI-6, levetiracetam, and procyclidine (termed the triple regimen) has previously been shown to work as a universal therapy against soman poisoning in rats, since it has capacities to function as both prophylactic and therapeutic measure. The purpose of the present study was to examine whether the triple regimen may have antidotal efficacy against intoxication by other classical nerve agents than soman. The treatment was given 1 and 5 min after exposure to a supralethal dose of nerve agents, and the results showed that the triple regimen successfully prevented or terminated seizures and preserved the lives of rats exposed to 5×LD50 of soman, sarin, cyclosarin, or VX, but solely 3×LD50 of tabun was managed by this regimen. To meet the particular antidotal requirements of tabun, the triple regimen was reinforced with obidoxime and was made to a quadruple regimen that effectively treated rats intoxicated by 5×LD50 of tabun. The rats recovered very well and the majority gained pre-exposure body weight within 7 days. Neuropathology was seen in all groups regardless of whether the rats seized or not. The most extensive damage was produced by sarin and cyclosarin. Differentiation between the nerve agents' potency to cause lesions was probably seen because the efficacious treatments ensured survival of supralethal poisoning. A combination of 2 oximes and 2 anticonvulsants may be a prerequisite to counteract effectively high levels of poisoning by any classical nerve agent. Copyright © 2015 Elsevier Inc. All rights reserved.

Microcystic adnexal carcinoma (MAC)-like squamous cell carcinoma as a differential diagnosis to Bell´s palsy: review of guidelines for refractory facial nerve palsy.

PubMed

Mueller, S K; Iro, H; Lell, M; Seifert, F; Bohr, C; Scherl, C; Agaimy, A; Traxdorf, M

2017-01-05

Bell´s palsy is the most common cause of facial paralysis worldwide and the most common disorder of the cranial nerves. It is a diagnosis of exclusion, accounting for 60-75% of all acquired peripheral facial nerve palsies. Our case shows the first case of a microcystic adnexal carcinoma-like squamous cell carcinoma as a cause of facial nerve palsy. The patient, a 70-year-old Caucasian male, experienced subsequent functional impairment of the trigeminal and the glossopharyngeal nerve about 1½ years after refractory facial nerve palsy. An extensive clinical work-up and tissue biopsy of the surrounding parotid gland tissue was not able to determine the cause of the paralysis. Primary infiltration of the facial nerve with subsequent spreading to the trigeminal and glossopharyngeal nerve via neuroanastomoses was suspected. After discussing options with the patient, the main stem of the facial nerve was resected to ascertain the diagnosis of MAC-like squamous cell carcinoma, and radiochemotherapy was subsequently started. This case report shows that even rare neoplastic etiologies should be considered as a cause of refractory facial nerve palsy and that it is necessary to perform an extended diagnostic work-up to ascertain the diagnosis. This includes high-resolution MRI imaging and, as perilesional parotid biopsies might be inadequate for rare cases like ours, consideration of a direct nerve biopsy to establish the right diagnosis.

Novel Model of Somatosensory Nerve Transfer in the Rat.

PubMed

Paskal, Adriana M; Paskal, Wiktor; Pelka, Kacper; Podobinska, Martyna; Andrychowski, Jaroslaw; Wlodarski, Pawel K

2018-05-09

Nerve transfer (neurotization) is a reconstructive procedure in which the distal denervated nerve is joined with a proximal healthy nerve of a less significant function. Neurotization models described to date are limited to avulsed roots or pure motor nerve transfers, neglecting the clinically significant mixed nerve transfer. Our aim was to determine whether femoral-to-sciatic nerve transfer could be a feasible model of mixed nerve transfer. Three Sprague Dawley rats were subjected to unilateral femoral-to-sciatic nerve transfer. After 50 days, functional recovery was evaluated with a prick test. At the same time, axonal tracers were injected into each sciatic nerve distally to the lesion site, to determine nerve fibers' regeneration. In the prick test, the rats retracted their hind limbs after stimulation, although the reaction was moderately weaker on the operated side. Seven days after injection of axonal tracers, dyes were visualized by confocal microscopy in the spinal cord. Innervation of the recipient nerve originated from higher segments of the spinal cord than that on the untreated side. The results imply that the femoral nerve axons, ingrown into the damaged sciatic nerve, reinnervate distal targets with a functional outcome.

[Sex difference of functional and structural alterations in the myocardium of rats with hypothyroidism].

PubMed

Khara, M R; Pavlovych, S I; Mykhaĭliuk, V M

2013-01-01

In experiments on sexually mature rats we studied specific cholinergic regulations of the heart and the degree of its structural damage in hypothyroidism, depending on gender and hormone-productive activity of the gonads. Hypothyroidism in sexually mature males and females was modelled with mercazolil intragastric administration (75 mg/kg) daily during 15 days. We also studied the intensity of bradycardia, which occurred in response to electrical stimulation of vagus nerve and intravenous acetylcholine administration. The degree of structural heart damage was assessed by the percentage of damaged cardiomyocytes in the ventricles of myocardium. It was found that one of the mechanisms of bradycardia in merkazolil-induced hypothyroidism is an increase of the sensitivity of sinus node cholinergic receptors and release of more quanta of acetylcholine from stimulated nerves vagus endings, what was more intense in females. The intensity of bradycardia in hypothyroidism was more significant in gonadectomized animals than in individuals with preserved gonads. The mechanisms of its occurrence in males consist of release of greater amount of acetylcholine from the endings of the nerves vagus, and in females it was the result of significant increase of the sensitivity of sinus node cholinergic receptors. Regardless of the gonads activity, structural damage of the myocardium in merkazolil-induced hypothyroidism was more intensive in female rats.

Subxiphoid approach for spontaneous bilateral pneumothorax: a case report.

PubMed

Fok, Matthew; Karunanantham, Jay; Ali, Jason M; Concina, Serena; Jayakumar, Shruti; Peryt, Adam; Coonar, Aman; Aresu, Giuseppe

2017-01-01

The development of video-assisted thoracoscopic surgery (VATS) has contributed to reduced pain and improved recovery following thoracic surgery. However, pain remains a major issue. Patients with bilateral pulmonary pathology requiring operative intervention may have even more pain due to bilateral transthoracic incisions. The recently described uniportal subxiphoid VATS approach provides an opportunity to undertake bilateral thoracic surgery through a single incision that avoids the bilateral intercostal nerve damage caused by transthoracic incision and drainage. Here we report a case of a patient requiring bilateral bullectomy and pleurectomy for the management of pneumothorax that was performed successfully by the subxiphoid VATS approach.

Chronic recording of regenerating VIIIth nerve axons with a sieve electrode

NASA Technical Reports Server (NTRS)

Mensinger, A. F.; Anderson, D. J.; Buchko, C. J.; Johnson, M. A.; Martin, D. C.; Tresco, P. A.; Silver, R. B.; Highstein, S. M.

2000-01-01

A micromachined silicon substrate sieve electrode was implanted within transected toadfish (Opsanus tau) otolith nerves. High fidelity, single unit neural activity was recorded from seven alert and unrestrained fish 30 to 60 days after implantation. Fibrous coatings of genetically engineered bioactive protein polymers and nerve guide tubes increased the number of axons regenerating through the electrode pores when compared with controls. Sieve electrodes have potential as permanent interfaces to the nervous system and to bridge missing connections between severed or damaged nerves and muscles. Recorded impulses might also be amplified and used to control prosthetic devices.

Risk of Damage to the Somatic Innervation of the Penis during the AdVanceProcedure: An Anatomical Study.

PubMed

Hogewoning, Cornelis R C; Elzevier, Henk W; Pelger, Rob C M; Bekker, Milou D; DeRuiter, Marco C

2015-08-01

One of the methods to treat post radical prostatectomy stress urinary incontinence is the AdVance (American Medical Systems, Minnetonka, MN, USA) male sling procedure. During this procedure, the somatic innervation of the penis may be at risk for injury. Six AdVance procedures were performed in six donated bodies at the Anatomy and Embryology Department of the Leiden University Medical Centre. The pelves were dissected and the shortest distance between the sling and the dorsal nerve of the penis (DNP) was documented. The aim of this study was to describe the anatomical relation between the AdVance male sling and penile nerves based on the dissection of six adult male pelves. The AdVance male sling procedure was conducted in six donated male bodies. After placement, the pelves were dissected and the shortest distance between sling and the DNP was documented. The main outcome measure was the distance between the AdVance male sling and the DNP. The mean distance of the sling to the DNP was 4.1 mm and was found situated directly next to the nerve (distance 0 mm) in 4 out of 12 (33%) hemipelves. The distance of the sling to the obturator neurovascular bundle was 30 mm or more in all six bodies. Damage to the DNP caused by the AdVance male sling procedure appears to be an extremely rare complication, which has not been described in current literature. The proximity of the AdVance to the DNP could, however, pose a risk that should be taken into consideration by physicians and patients when opting for surgery. © 2015 International Society for Sexual Medicine.

Diet-induced obesity and low testosterone increase neuroinflammation and impair neural function.

PubMed

Jayaraman, Anusha; Lent-Schochet, Daniella; Pike, Christian J

2014-09-16

Low testosterone and obesity are independent risk factors for dysfunction of the nervous system including neurodegenerative disorders such as Alzheimer's disease (AD). In this study, we investigate the independent and cooperative interactions of testosterone and diet-induced obesity on metabolic, inflammatory, and neural health indices in the central and peripheral nervous systems. Male C57B6/J mice were maintained on normal or high-fat diet under varying testosterone conditions for a four-month treatment period, after which metabolic indices were measured and RNA isolated from cerebral cortex and sciatic nerve. Cortices were used to generate mixed glial cultures, upon which embryonic cerebrocortical neurons were co-cultured for assessment of neuron survival and neurite outgrowth. Peripheral nerve damage was determined using paw-withdrawal assay, myelin sheath protein expression levels, and Na+,K+-ATPase activity levels. Our results demonstrate that detrimental effects on both metabolic (blood glucose, insulin sensitivity) and proinflammatory (cytokine expression) responses caused by diet-induced obesity are exacerbated by testosterone depletion. Mixed glial cultures generated from obese mice retain elevated cytokine expression, although low testosterone effects do not persist ex vivo. Primary neurons co-cultured with glial cultures generated from high-fat fed animals exhibit reduced survival and poorer neurite outgrowth. In addition, low testosterone and diet-induced obesity combine to increase inflammation and evidence of nerve damage in the peripheral nervous system. Testosterone and diet-induced obesity independently and cooperatively regulate neuroinflammation in central and peripheral nervous systems, which may contribute to observed impairments in neural health. Together, our findings suggest that low testosterone and obesity are interactive regulators of neuroinflammation that, in combination with adipose-derived inflammatory pathways and other factors, increase the risk of downstream disorders including type 2 diabetes and Alzheimer's disease.

Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures.

PubMed

Gali, Rajasekhar; Devireddy, Sathya Kumar; Venkata, Kishore Kumar Rayadurgam; Kanubaddy, Sridhar Reddy; Nemaly, Chaithanyaa; Dasari, Mallikarjuna

2016-01-01

Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP) approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a) the ease of access for retrieval, reimplantation and fixation of the proximal segment; b) the postoperative approach related complications; c) the adequacy of anatomical reduction and stability of fixation; d) the occlusal changes; and the e) TMJ function and radiological changes. Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch) palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby permitting perpendicular placement of screws with minimal risk of damage to the facial nerve.

Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures

PubMed Central

Gali, Rajasekhar; Devireddy, Sathya Kumar; Venkata, Kishore Kumar Rayadurgam; Kanubaddy, Sridhar Reddy; Nemaly, Chaithanyaa; Dasari, Mallikarjuna

2016-01-01

Introduction: Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. Purpose: This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP) approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. Patients and Methods: This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a) the ease of access for retrieval, reimplantation and fixation of the proximal segment; b) the postoperative approach related complications; c) the adequacy of anatomical reduction and stability of fixation; d) the occlusal changes; and the e) TMJ function and radiological changes. Results: Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch) palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. Conclusion: The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby permitting perpendicular placement of screws with minimal risk of damage to the facial nerve. PMID:27274123

Intraoperative identification of the facial nerve by needle electromyography stimulation with a burr

PubMed Central

KHAMGUSHKEEVA, N.N.; ANIKIN, I.A.; KORNEYENKOV, A.A.

2016-01-01

The purpose of this research is to improve the safety of surgery for patients with a pathology of the middle and inner ear by preventing damage to the facial nerve by conducting intraoperative monitoring of the facial nerve by needle electromyography with continuous stimulation with a burr. Patients and Methods The clinical part of the prospective study was carried out on 48 patients that were diagnosed with suppurative otitis media. After the surgery with intraoperative monitoring, the facial nerve with an intact bone wall was stimulated electrically in the potentially dangerous places of damage. Minimum (threshold) stimulation (mA) of the facial nerve with a threshold event of 100 μV was used to register EMG events. The anatomical part of the study was carried out on 30 unformalinized cadaver temporal bones from adult bodies. The statistical analysis of obtained data was carried out with parametric methods (Student’s t-test), non-parametric correlation (Spearman’s method) and regression analysis. Results It was found that 1 mA of threshold amperage corresponded to 0.8 mm thickness of the bone wall of the facial canal. Values of transosseous threshold stimulation in potentially dangerous sections of the injury to the facial nerve were obtained. Conclusion These data lower the risk of paresis (paralysis) of the facial muscles during otologic surgery. PMID:27142821

Visual and neurologic sequelae of methanol poisoning in Saudi Arabia

PubMed Central

Galvez-Ruiz, Alberto; Elkhamary, Sahar M.; Asghar, Nasira; Bosley, Thomas M.

2015-01-01

Objectives: To present the visual sequelae of methanol poisoning and to emphasize the characteristics of methanol exposure in the Kingdom of Saudi Arabia (KSA). Methods: A retrospective case series was carried out on 50 sequential patients with methanol poisoning seen at the King Khaled Eye Specialist Hospital and King Saud University Hospitals in Riyadh, KSA between 2008 and 2014. All patients were examined by a neuro-ophthalmologist at least one month after methanol intoxication. Results: All 50 patients were young or middle-aged males. All admitted to drinking unbranded alcohol within 2-3 days before profound or relatively profound, painless, bilateral visual loss. Mean visual acuity in this group was hand motions (logMAR 2.82; range 0.1 - 5.0) with some eye to eye variability within individuals. Worse visual acuity was correlated with advancing age (Pearson correlation: oculus dextrus [right eye] - 0.37, p=0.008; oculus sinister [left eye] - 0.36, p=0.011). All patients had optic atrophy bilaterally, and all tested patients had visual field defects. Tremors with or without rigidity were present in 12 patients, and 11 of 30 patients who had neuroimaging performed had evidence of putaminal necrosis. Conclusion: Methanol intoxication causes visual loss within 12-48 hours due to relatively severe, painless, bilateral optic nerve damage that may be somewhat variable between eyes, and is generally worse with advancing age. The coincidence of bilateral optic nerve damage and bilateral putaminal necrosis in a young or middle-aged male is very suspicious for methanol-induced damage. PMID:25935177

Pure neuritic leprosy presenting as ulnar nerve neuropathy: a case report of electrodiagnostic, radiographic, and histopathological findings.

PubMed

Payne, Russell; Baccon, Jennifer; Dossett, John; Scollard, David; Byler, Debra; Patel, Akshal; Harbaugh, Kimberly

2015-11-01

Hansen's disease, or leprosy, is a chronic infectious disease with many manifestations. Though still a major health concern and leading cause of peripheral neuropathy in the developing world, it is rare in the United States, with only about 150 cases reported each year. Nevertheless, it is imperative that neurosurgeons consider it in the differential diagnosis of neuropathy. The causative organism is Mycobacterium leprae, which infects and damages Schwann cells in the peripheral nervous system, leading first to sensory and then to motor deficits. A rare presentation of Hansen's disease is pure neuritic leprosy. It is characterized by nerve involvement without the characteristic cutaneous stigmata. The authors of this report describe a case of pure neuritic leprosy presenting as ulnar nerve neuropathy with corresponding radiographic, electrodiagnostic, and histopathological data. This 11-year-old, otherwise healthy male presented with progressive right-hand weakness and numbness with no cutaneous abnormalities. Physical examination and electrodiagnostic testing revealed findings consistent with a severe ulnar neuropathy at the elbow. Magnetic resonance imaging revealed diffuse thickening and enhancement of the ulnar nerve and narrowing at the cubital tunnel. The patient underwent ulnar nerve decompression with biopsy. Pathology revealed acid-fast organisms within the nerve, which was pathognomonic for Hansen's disease. He was started on antibiotic therapy, and on follow-up he had improved strength and sensation in the ulnar nerve distribution. Pure neuritic leprosy, though rare in the United States, should be considered in the differential diagnosis of those presenting with peripheral neuropathy and a history of travel to leprosy-endemic areas. The long incubation period of M. leprae, the ability of leprosy to mimic other conditions, and the low sensitivity of serological tests make clinical, electrodiagnostic, and radiographic evaluation necessary for diagnosis. Prompt diagnosis and treatment is imperative to prevent permanent neurological injury.

Effects of cryoanalgesia on post-thoracotomy pain and on the structure of intercostal nerves: a human prospective randomized trial and a histological study.

PubMed

Moorjani, N; Zhao, F; Tian, Y; Liang, C; Kaluba, J; Maiwand, M O

2001-09-01

The choice of analgesia in the management of post-thoracotomy pain remains controversial. Although several alternative forms of post-thoracotomy analgesia exist, all have their disadvantages. Cryoanalgesia, localized freezing of intercostal nerves, has been reported to have variable effectiveness and an incidence of long-term cutaneous sensory changes. We carried out an animal study to assess the reversibility of histological changes induced by cryoanalgesia and a prospective randomized trial to compare the effectiveness of cryoanalgesia with conventional analgesia (parenteral opiates). In six anaesthetized dogs, intercostal nerves were exposed to a varying duration of cryo-application (30, 60, 90 and 120 s). The nerves were biopsied and examined histologically at regular intervals over the following 6 months. In the clinical study, 200 consecutive patients undergoing thoracotomy were randomized to cryoanalgesia and conventional (parenteral opiates) analgesia groups. Postoperative pain scores, respiratory function tests and use of opiate analgesia were measured for the two groups. Following application of the cryoprobe, degeneration and fragmentation of the axons was evident with associated inflammatory changes. As the endoneurium remained intact, axonal regeneration took place after the resolution of axonal swelling. Over the course of weeks, recovery of the intercostal nerve occurred and was complete after 1 month for the 30 and 60 s groups. For nerves exposed to longer durations of cryoanalgesia, the time taken for complete recovery was proportionally increased. Clinically, there was a statistically significant (P<0.05) improvement in postoperative pain scores and use of opiate analgesia and an improvement (P>0.05) in respiratory function tests for patients in the cryoanalgesia group. The previously suggested cutaneous sensory changes resolved within 6 months with complete restoration of function. We suggest that cryoanalgesia be considered as a simple, inexpensive, long-term form of post-thoracotomy pain relief, which does not cause any long-term histological damage to intercostal nerves.

Ablation of the sphenopalatine ganglion does not attenuate the infarct reducing effect of vagus nerve stimulation

PubMed Central

Ay, Ilknur; Ay, Hakan

2013-01-01

Electrical stimulation of the cervical vagus nerve reduces infarct size by approximately 50% after cerebral ischemia in rats. The mechanism of ischemic protection by vagus nerve stimulation (VNS) is not known. In this study, we investigated whether the infarct reducing effect of VNS was mediated by activation of the parasympathetic vasodilator fibers that originate from the sphenopalatine ganglion (SPG) and innervate the anterior cerebral circulation. We examined the effects of electrical stimulation of the cervical vagus nerve in two groups of rats: one with and one without SPG ablation. Electrical stimulation was initiated 30 min after induction of ischemia, and lasted for 1h. Measurement of infarct size 24h later revealed that the volume of ischemic damage was smaller in those animals that received VNS treatment (41.32 ± 2.07% vs. 24.19 ± 2.62% of the contralateral hemispheric volume, n=6 in both; p<0.05). SPG ablation did not abolish this effect; the reduction in infarct volume following VNS was 58% in SPG-damaged animals, 41% in SPG-intact animals (p>0.05). In both SPG-intact and SPG-damaged animals VNS treatment resulted in better motor outcome (p<0.05 vs. corresponding controls for both). Our findings show that VNS can protect the brain against acute ischemic injury, and that this effect is not mediated by SPG projections. PMID:23273773

A 63-year-old man with peripheral facial nerve paralysis and a pulmonary lesion.

PubMed

Yserbyt, J; Wilms, G; Lievens, Y; Nackaerts, K

2009-01-01

Occasionally, malignant neoplasms may cause peripheral facial nerve paralysis as a presenting symptom. A 63-year-old man was referred to the Emergency Department because of a peripheral facial nerve paralysis, lasting for 10 days. Initial diagnostic examinations revealed no apparent cause for this facial nerve paralysis. Chest X-ray, however, showed a suspicious tumoural mass, located in the right hilar region, as confirmed by CAT scan. The diagnosis of an advanced stage lung adenocarcinoma was finally confirmed by bronchial biopsy. MRI scanning showed diffuse brain metastases and revealed a pontine lesion as the most probable underlying cause of this case of peripheral facial nerve paralysis. Platin-based palliative chemotherapy was given, after an initial pancranial irradiation. According to the MRI findings, the pontine lesion was responsible for the peripheral facial nerve paralysis, as an initial presenting symptom in this case of lung adenocarcinoma. This clinical case of a peripheral facial nerve paralysis was caused by a pontine brain metastasis and illustrates a rather rare presenting symptom of metastatic lung cancer.

Noise Induced DNA Damage Within the Auditory Nerve.

PubMed

Guthrie, O'neil W

2017-03-01

An understanding of the molecular pathology that underlies noise induced neurotoxicity is a prerequisite to the design of targeted therapies. The objective of the current experiment was to determine whether or not DNA damage is part of the pathophysiologic sequela of noise induced neurotoxicity. The experiment consisted of 41 hooded Long-Evans rats (2 month old males) that were randomized into control and noise exposed groups. Both the control and the noise group followed the same time schedule and therefore started and ended the experiment together. The noise dose consisted of a 6000 Hz noise band at 105 dB SPL. Temporal bones from both groups were harvested, and immunohistochemistry was used to identify neurons with DNA damage. Quantitative morphometric analyses was then employed to determine the level of DNA damage. Neural action potentials were recorded to assess the functional impact of noise induced DNA damage. Immunohistochemical reactions revealed that the noise exposure precipitated DNA damage within the nucleus of auditory neurons. Quantitative morphometry confirmed the noise induced increase in DNA damage levels and the precipitation of DNA damage was associated with a significant loss of nerve sensitivity. Therefore, DNA damage is part of the molecular pathology that drives noise induced neurotoxicity. Anat Rec, 300:520-526, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

PubMed Central

Nevo, Zvi

2014-01-01

Objective. Guiding Regeneration Gel (GRG) was developed in response to the clinical need of improving treatment for peripheral nerve injuries and helping patients regenerate massive regional losses in peripheral nerves. The efficacy of GRG based on tissue engineering technology for the treatment of complete peripheral nerve injury with significant loss defect was investigated. Background. Many severe peripheral nerve injuries can only be treated through surgical reconstructive procedures. Such procedures are challenging, since functional recovery is slow and can be unsatisfactory. One of the most promising solutions already in clinical practice is synthetic nerve conduits connecting the ends of damaged nerve supporting nerve regeneration. However, this solution still does not enable recovery of massive nerve loss defect. The proposed technology is a biocompatible and biodegradable gel enhancing axonal growth and nerve regeneration. It is composed of a complex of substances comprising transparent, highly viscous gel resembling the extracellular matrix that is almost impermeable to liquids and gasses, flexible, elastic, malleable, and adaptable to various shapes and formats. Preclinical study on rat model of peripheral nerve injury showed that GRG enhanced nerve regeneration when placed in nerve conduits, enabling recovery of massive nerve loss, previously unbridgeable, and enabled nerve regeneration at least as good as with autologous nerve graft “gold standard” treatment. PMID:25105121

Optic nerve head axonal transport in rabbits with hereditary glaucoma.

PubMed

Bunt-Milam, A H; Dennis, M B; Bensinger, R E

1987-04-01

Rabbits with hereditary glaucoma develop ocular changes that resemble human congenital glaucoma and buphthalmia. The inheritance is autosomal recessive (bu). Previous research was performed primarily on albino bu/bu rabbits that were unhealthy and bred poorly. We have bred pigmented bu/bu rabbits to determine if this would improve hardiness and provide a better model for the disease in humans. First-generation offspring from matings of bu/bu albino with bu/bu pigmented rabbits were all affected, indicating that the bu gene is found at the same locus in both strains. The pigmented bu/bu offspring had a high degree of mortality, as reported previously for albino bu/bu rabbits. Newborn bu/bu rabbits initially had normal intraocular pressure (IOP; 15-23 mmHg); after 1- to 3 months, the IOP increased to 26-48 mmHg. The eyes became buphthalmic and the IOP returned to normal or sub-normal levels after 6-10 months. Since the lamina cribrosa is absent or poorly formed in the rabbit optic nerve head (ONH), this model was used to test the role of mechanical factors in the etiology of ONH pathology caused by increased IOP. Orthograde axonal transport was evaluated in both eyes from eight normal and 24 bu/bu rabbits of different ages, using intravitreal injections of [3H]leucine to mark orthograde axonal transport, followed by light- and electron-microscopic radioautography of the ONHs and superior colliculi. Normal rabbits of all ages showed no blockage of axonal transport in the ONH. All optic axons from young bu/bu rabbits with normal IOP and most axons from older buphthalmic rabbits that previously had elevated IOP were normal morphologically. Small zones of transport blockage occurred in bu/bu eyes while IOP was elevated; most affected axons lay immediately adjacent to ONH connective tissue beams that radiate outward from the central retinal vessels to the optic-nerve sheath. Thus, the rabbit, which lacks a true lamina cribrosa, does not show marked blockage of axonal transport as occurs in the LS of the monkey and cat ONH when IOP is elevated acutely. This anatomic difference appears to be protective against axonal damage, since bu/bu rabbits with chronic IOP elevation did not show significant loss of optic axons. These results are consistent with the proposed 'mechanical' theory of ONH damage resulting from increased IOP. Electron-microscopic radioautography revealed that chronically elevated IOP in bu/bu rabbits, which caused small foci of blocked ONH axonal transport against ONH beams, also caused degeneration of a few optic nerve terminals in the superior colliculi as the disease progressed.(ABSTRACT TRUNCATED AT 400 WORDS)

The phrenic nerve with accompanying vessels: a silent cause of cardiovascular border obliteration on chest radiography.

PubMed

Farhana, Shiri; Ashizawa, Kazuto; Hayashi, Hideyuki; Ogihara, Yukihiro; Aso, Nobuya; Hayashi, Kuniaki; Uetani, Masataka

2015-12-01

Our aim was to clarify the frequency of cardiovascular border obliteration on frontal chest radiography and to prove that the phrenic nerve with accompanying vessels can be considered as a cause of obliteration of cardiovascular border on an otherwise normal chest radiography. Two radiologists reviewed chest radiographs and computed tomography (CT) images of 100 individuals. CT confirmed the absence of intrapulmonary or extrapulmonary abnormalities in all of them. We examined the frequency of cardiovascular border obliteration on frontal chest radiography and summarized the causes of obliteration as pericardial fat pad, phrenic nerve, intrafissure fat, pulmonary vessels, and others, comparing them with CT in each case. Cardiovascular border was obliterated on frontal chest radiography in 46 cases on the right and in 61 on the left. The phrenic nerve with accompanying vessels was found to be a cause of obliteration in 34 of 46 cases (74%) on the right and 29 of 61 (48%) cases on the left. The phrenic nerve was the most frequent cause of cardiovascular border obliteration on both sides. The phrenic nerve with accompanying vessels, forming a prominent fold of parietal pleura, can be attributed as a cause of cardiovascular border obliteration on frontal chest radiography.

Silicone Molding and Lifetime Testing of Peripheral Nerve Interfaces for Neuroprostheses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupte, Kimaya; Tolosa, Vanessa

Implantable peripheral nerve cuffs have a large application in neuroprostheses as they can be used to restore sensation to those with upper limb amputations. Modern day prosthetics, while lessening the pain associated with phantom limb syndrome, have limited fine motor control and do not provide sensory feedback to patients. Sensory feedback with prosthetics requires communication between the nervous system and limbs, and is still a challenge to accomplish with amputees. Establishing this communication between the peripheral nerves in the arm and artificial limbs is vital as prosthetics research aims to provide sensory feedback to amputees. Peripheral nerve cuffs restore sensationmore » by electrically stimulating certain parts of the nerve in order to create feeling in the hand. Cuff electrodes have an advantage over standard electrodes as they have high selective stimulation by bringing the electrical interface close to the neural tissue in order to selectively activate targeted regions of a peripheral nerve. In order to further improve the selective stimulation of these nerve cuffs, there is need for finer spatial resolution among electrodes. One method to achieve a higher spatial resolution is to increase the electrode density on the cuff itself. Microfabrication techniques can be used to achieve this higher electrode density. Using L-Edit, a layout editor, microfabricated peripheral nerve cuffs were designed with a higher electrode density than the current model. This increase in electrode density translates to an increase in spatial resolution by at least one order of magnitude. Microfabricated devices also have two separate components that are necessary to understand before implantation: lifetime of the device and assembly to prevent nerve damage. Silicone molding procedures were optimized so that devices do not damage nerves in vivo, and lifetime testing was performed on test microfabricated devices to determine their lifetime in vivo. Future work of this project would include fabricating some of the designed devices and seeing how they compare to the current cuffs in terms of their electrical performance, lifetime, shape, and mechanical properties.« less

Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy

PubMed Central

Barth, Connor W.; Gibbs, Summer L.

2017-01-01

Nerve damage remains a major morbidity following nerve sparing radical prostatectomy, significantly affecting quality of life post-surgery. Nerve-specific fluorescence guided surgery offers a potential solution by enhancing nerve visualization intraoperatively. However, the prostate is highly innervated and only the cavernous nerve structures require preservation to maintain continence and potency. Systemic administration of a nerve-specific fluorophore would lower nerve signal to background ratio (SBR) in vital nerve structures, making them difficult to distinguish from all nervous tissue in the pelvic region. A direct administration methodology to enable selective nerve highlighting for enhanced nerve SBR in a specific nerve structure has been developed herein. The direct administration methodology demonstrated equivalent nerve-specific contrast to systemic administration at optimal exposure times. However, the direct administration methodology provided a brighter fluorescent nerve signal, facilitating nerve-specific fluorescence imaging at video rate, which was not possible following systemic administration. Additionally, the direct administration methodology required a significantly lower fluorophore dose than systemic administration, that when scaled to a human dose falls within the microdosing range. Furthermore, a dual fluorophore tissue staining method was developed that alleviates fluorescence background signal from adipose tissue accumulation using a spectrally distinct adipose tissue specific fluorophore. These results validate the use of the direct administration methodology for specific nerve visualization with fluorescence image-guided surgery, which would improve vital nerve structure identification and visualization during nerve sparing radical prostatectomy. PMID:28255352

Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy.

PubMed

Barth, Connor W; Gibbs, Summer L

2017-01-01

Nerve damage remains a major morbidity following nerve sparing radical prostatectomy, significantly affecting quality of life post-surgery. Nerve-specific fluorescence guided surgery offers a potential solution by enhancing nerve visualization intraoperatively. However, the prostate is highly innervated and only the cavernous nerve structures require preservation to maintain continence and potency. Systemic administration of a nerve-specific fluorophore would lower nerve signal to background ratio (SBR) in vital nerve structures, making them difficult to distinguish from all nervous tissue in the pelvic region. A direct administration methodology to enable selective nerve highlighting for enhanced nerve SBR in a specific nerve structure has been developed herein. The direct administration methodology demonstrated equivalent nerve-specific contrast to systemic administration at optimal exposure times. However, the direct administration methodology provided a brighter fluorescent nerve signal, facilitating nerve-specific fluorescence imaging at video rate, which was not possible following systemic administration. Additionally, the direct administration methodology required a significantly lower fluorophore dose than systemic administration, that when scaled to a human dose falls within the microdosing range. Furthermore, a dual fluorophore tissue staining method was developed that alleviates fluorescence background signal from adipose tissue accumulation using a spectrally distinct adipose tissue specific fluorophore. These results validate the use of the direct administration methodology for specific nerve visualization with fluorescence image-guided surgery, which would improve vital nerve structure identification and visualization during nerve sparing radical prostatectomy.

Protective effect of arctigenin on ethanol-induced neurotoxicity in PC12 cells.

PubMed

Huang, Jia; Xiao, Lan; Wei, Jing-Xiang; Shu, Ya-Hai; Fang, Shi-Qi; Wang, Yong-Tang; Lu, Xiu-Min

2017-04-01

As a neurotropic substance, ethanol can damage nerve cells through an increase in the production of free radicals, interference of neurotrophic factor signaling pathways, activation of endogenous apoptotic signals and other molecular mechanisms. Previous studies have revealed that a number of natural drugs extracted from plants offer protection of nerve cells from damage. Among these, arctigenin (ATG) is a lignine extracted from Arctium lappa (L.), which has been found to exert a neuroprotective effect on scopolamine‑induced memory deficits in mice with Alzheimer's disease and glutamate-induced neurotoxicity in primary neurons. As a result, it may offer beneficial effects on ethanol-induced neurotoxicity. However, the effects of ATG on ethanol‑induced nerve damage remain to be elucidated. To address this issue, the present study used rat pheochromocytoma PC12 cells to investigate the neuroprotective effects of ATG on ethanol-induced cell damage by performing an MTT reduction assay, cell cycle analysis, Hoechst33342/propidium iodide fluorescence staining and flow cytometry to examine apoptosis. The results showed that 10 µM ATG effectively promoted the proliferation of damaged cells, and increased the distribution ratio of the cells at the G2/M and S phases (P<0.05). In addition, the apoptosis and necrosis of the PC12 cells were significantly decreased following treatment with ATG. Therefore, it was concluded that 10 µM ATG had a protective effect on ethanol‑induced injury in PC12 cells.

Optical cuff for optogenetic control of the peripheral nervous system.

PubMed

Michoud, Frédéric; Sottas, Loïc; Browne, Liam E; Asboth, Léonie; Latremoliere, Alban; Sakuma, Miyuki; Courtine, Grégoire; Woolf, Clifford J; Lacour, Stéphanie P

2018-02-01

Nerves in the peripheral nervous system (PNS) contain axons with specific motor, somatosensory and autonomic functions. Optogenetics offers an efficient approach to selectively activate axons within the nerve. However, the heterogeneous nature of nerves and their tortuous route through the body create a challenging environment to reliably implant a light delivery interface. Here, we propose an optical peripheral nerve interface-an optocuff-, so that optogenetic modulation of peripheral nerves become possible in freely behaving mice. Using this optocuff, we demonstrate orderly recruitment of motor units with epineural optical stimulation of genetically targeted sciatic nerve axons, both in anaesthetized and in awake, freely behaving animals. Behavioural experiments and histology show the optocuff does not damage the nerve thus is suitable for long-term experiments. These results suggest that the soft optocuff might be a straightforward and efficient tool to support more extensive study of the PNS using optogenetics.

Optical cuff for optogenetic control of the peripheral nervous system

NASA Astrophysics Data System (ADS)

Michoud, Frédéric; Sottas, Loïc; Browne, Liam E.; Asboth, Léonie; Latremoliere, Alban; Sakuma, Miyuki; Courtine, Grégoire; Woolf, Clifford J.; Lacour, Stéphanie P.

2018-02-01

Objective. Nerves in the peripheral nervous system (PNS) contain axons with specific motor, somatosensory and autonomic functions. Optogenetics offers an efficient approach to selectively activate axons within the nerve. However, the heterogeneous nature of nerves and their tortuous route through the body create a challenging environment to reliably implant a light delivery interface. Approach. Here, we propose an optical peripheral nerve interface—an optocuff—, so that optogenetic modulation of peripheral nerves become possible in freely behaving mice. Main results. Using this optocuff, we demonstrate orderly recruitment of motor units with epineural optical stimulation of genetically targeted sciatic nerve axons, both in anaesthetized and in awake, freely behaving animals. Behavioural experiments and histology show the optocuff does not damage the nerve thus is suitable for long-term experiments. Significance. These results suggest that the soft optocuff might be a straightforward and efficient tool to support more extensive study of the PNS using optogenetics.

CHRONIC PERIPHERAL NERVE COMPRESSION DISRUPTS PARANODAL AXOGLIAL JUNCTIONS

PubMed Central

Otani, Yoshinori; Yermakov, Leonid M.; Dupree, Jeffrey L.; Susuki, Keiichiro

2016-01-01

Introduction Peripheral nerves are often exposed to mechanical stress leading to compression neuropathies. The pathophysiology underlying nerve dysfunction by chronic compression is largely unknown. Methods We analyzed molecular organization and fine structures at and near nodes of Ranvier in a compression neuropathy model in which a silastic tube was placed around the mouse sciatic nerve. Results Immunofluorescence study showed that clusters of cell adhesion complex forming paranodal axoglial junctions were dispersed with frequent overlap with juxtaparanodal components. These paranodal changes occurred without internodal myelin damage. The distribution and pattern of paranodal disruption suggests that these changes are the direct result of mechanical stress. Electron microscopy confirmed loss of paranodal axoglial junctions. Discussion Our data show that chronic nerve compression disrupts paranodal junctions and axonal domains required for proper peripheral nerve function. These results provide important clues toward better understanding of the pathophysiology underlying nerve dysfunction in compression neuropathies. PMID:27463510

Treatment of great auricular neuralgia with real-time ultrasound-guided great auricular nerve block

PubMed Central

Jeon, Younghoon; Kim, Saeyoung

2017-01-01

Abstract Rationale: The great auricular nerve can be damaged by the neck surgery, tumor, and long-time pressure on the neck. But, great auricular neuralgia is very rare condition. It was managed by several medication and landmark-based great auricular nerve block with poor prognosis. Patient concerns: A 25-year-old man presented with a pain in the left lateral neck and auricle. Diagnosis: He was diagnosed with great auricular neuralgia. Interventions: His pain was not reduced by medication. Therefore, the great auricular nerve block with local anesthetics and steroid was performed under ultrasound guidance. Outcomes: Ultrasound guided great auricular nerve block alleviated great auricular neuralgia. Lessons: This medication-resistant great auricular neuralgia was treated by the ultrasound guided great auricular nerve block with local anesthetic agent and steroid. Therefore, great auricular nerve block can be a good treatment option of medication resistant great auricular neuralgia. PMID:28328811

[Correlation between facial nerve functional evaluation and efficacy evaluation of acupuncture treatment for Bell's palsy].

PubMed

Zhou, Zhang-ling; Li, Cheng-xin; Jiang, Yue-bo; Zuo, Cong; Cai, Yun; Wang, Rui

2012-09-01

To assess and grade facial nerve dysfunction according to the extent of facial paralysis in the clinical course of acupuncture treatment for Bell's palsy, and to observe the interrelationship between the grade, the efficacy and the period of treatment, as well as the effect on prognosis. The authors employed the House-Brackmann scale, a commonly used evaluation scale for facial paralysis motor function, and set standards for eye fissure and lips. According to the improved scale, the authors assessed and graded the degree of facial paralysis in terms of facial nerve dysfunction both before and after treatment. The grade was divided into five levels: mild, moderate, moderately severe, severe dysfunction and complete paralysis. The authors gave acupuncture treatment according to the state of the disease without artificially setting the treatment period. The observation was focused on the efficacy and the efficacy was evaluated throughout the entire treatment process. Fifty-three cases out of 68 patients with Bell's palsy were cured and the overall rate of efficacy was 97%. Statistically significant differences (P<0.01) were perceived among the efficacy of five levels of facial nerve dysfunction. Efficacy was correlated with the damage level of the disease (correlation coefficient r=0.423, P<0.01). The course of treatment also extended with the severity of facial nerve dysfunction (P<0.01). Differences exist in patients with Bell's palsy in terms of severity of facial nerve dysfunction. Efficacy is reduced in correlation with an increase in facial nerve dysfunction, and the period of treatment varies in need of different levels of facial nerve dysfunction. It is highly necessary to assess and grade patients before observation and treatment in clinical study, and choose corresponding treatment according to severity of damage of the disease.

May the Inferior Petrosal Sinus Recanalization During Endovascular Treatment for Carotid-Cavernous Fistulas Increase the Risk of Sixth Nerve Palsy?

PubMed

Robert, Thomas; Valsecchi, Daniele; Sylvestre, Philippe; Blanc, Raphaël; Ciccio, Gabriele; Smajda, Stanislas; Redjem, Hocine; Piotin, Michel

2018-05-03

Sixth nerve palsy is a common complication of endovascular treatment for carotid-cavernous fistulas (CCF). Two hypotheses are evoked: the spontaneous venous congestion into the cavernous sinus and the direct compression of the nerve by the embolic agent into the cavernous sinus. Nevertheless, the evidence is still uncertain. Knowing the vicinity of the sixth nerve with the inferior petrosal sinus (IPS) in the Dorello canal, we hypothesized that the recanalization of the IPS increased the risk of nerve damage. We analyzed a prospective database of patients treated for CCFs from March 2009 to April 2016. We excluded patients who did not need treatment, cases of high-flow CCF, and patients lost to follow-up, obtaining a homogeneous population of 82 patients with indirect CCFs. This population was divided in 2 groups: patients without new-onset/worsening of sixth nerve palsy and patients with this postprocedural complication. Our main endpoints were the potential differences between patients with or without recanalization of IPS and between those who underwent or not an embolization with Onyx-18. We did not find any statistically meaningful difference between the 2 groups concerning the necessity of IPS recanalization (P > 0.999, odds ratio 0.97, 95% confidence interval 0.32-2.96) or with the use of Onyx-18 as an embolic agent (P = 0.56; odds ratio 1.41, 95% confidence interval 0.41-2.45). The recanalization of a thrombosed IPS does not increase the risk of procedural sixth nerve damage. The initial injury seems to relate with development/worsening of a sixth nerve palsy. Copyright © 2018 Elsevier Inc. All rights reserved.

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

PubMed

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.

Parathyroid adenoma

MedlinePlus

... the body. They do this by producing parathyroid hormone, or PTH. PTH helps control calcium, phosphorus, and vitamin D levels in the ... from surgery include: Damage to a nerve that controls your voice Damage to the parathyroid ... hormone) and low calcium level When to Contact a ...

[Morphologic studies of the protective role of catechin on kanamycin otoneurotoxicity in SD rats].

PubMed

Liu, Guo-hui; Xie, Ding-hua; Wu, Wei-jing

2002-12-28

To determine the protection of catechin on aminoglycoside antibiotics otoneurotoxicity in SD rats, and observe the morphologic changes of cochlear efferent nerve terminals and outer hair cells after the injection of kanamycin and the feeding of catechin by the stomach tube. Thirty-eight SD rats were randomly assigned into three experimental groups (KM-treated, catechin-treated, KM and catechin in combination) and one control group. The KM-treated group was given kanamycin in a dose of 500 mg.(kg.d)-1 for 14 days. The catechin-treated group was given catechin once by the stomach tube in a dose of 400 mg.(kg.d)-1. Two kinds of medicine were simultaneously given in the KM+ catechin group. Transmission electron microscopy was utilized to observe the subcellular structure of efferent nerve fibers and outer hair cells. The densities of efferent nerve fibers and terminals were examined and the numbers of efferent nerve fibers and terminals were numerated by the surface preparation using modified histochemical staining for acetylcholinesterase (AchE). The damage in the group protected by catechin was relieved compared with the unprotected group. No damage was found in the catechin-treated alone group and controls. The densities and numbers of efferent nerve fibers and terminals were obviously fewer in the unprotected group than in the protected group and controls(P < 0.05). There was no significant difference in the numbers of efferent nerve fibers and terminals of the group protected by catechin compared with the controls and the catechin-treated group (P > 0.05). Catechin significantly protects MOC efferent nerves in kanamycin otoneurotoxicity.

Artificial sensory organs: latest progress.

PubMed

Nakamura, Tatsuo; Inada, Yuji; Shigeno, Keiji

2018-03-01

This study introduces the latest progress on the study of artificial sensory organs, with a special emphasis on the clinical results of artificial nerves and the concept of in situ tissue engineering. Peripheral nerves have a strong potential for regeneration. An artificial nerve uses this potential to recover a damaged peripheral nerve. The polyglycolic acid collagen tube (PGA-C tube) is a bio-absorbable tube stuffed with collagen of multi-chamber structure that consists of thin collagen films. The clinical application of the PGA-C tube began in 2002 in Japan. The number of PGA-C tubes used is now beyond 300, and satisfactory results have been reported on peripheral nerve repairs. This PGA-C tube is also effective for patients suffering from neuropathic pain.

[Evaluating the risk of sciatic nerve damage in the rabbit by administration of low and intermediate energy extracorporeal shock waves].

PubMed

Rompe, J D; Bohl, J; Riehle, H M; Schwitalle, M; Krischek, O

1998-01-01

The aim of the study was to evaluate the likeliness for peripheral nerve lesions following extracorporeal shock wave application. 82 rabbit sciatic nerves were randomized to undergo low-energetic (0.08 mJ/mm2), middle-energetic (0.28 mJ/mm2) or no (controls) shock wave therapy. After 1 to 28 days an independent neuropathologist checked the specimen for signs of neural lesions. Only after 14 and 28 days vacuolic swelling of the axons was noted, somewhat pronounced in the middle-energetic group. In no case was there any disruption of the nerve's continuity. We did not observe any neurapraxia. Shock wave application does not threaten peripheral nerve integrity in an animal model.

Metal chelator combined with permeability enhancer ameliorates oxidative stress-associated neurodegeneration in rat eyes with elevated intraocular pressure

PubMed Central

Liu, P.; Zhang, M.; Shoeb, M.; Hogan, D.; Tang, Luosheng; Syed, M. F.; Wang, C. Z.; Campbell, G.A.; Ansari, N.H.

2014-01-01

Since as many as half of glaucoma patients on intraocular pressure (IOP)-lowering therapy continue to experience optic nerve toxicity, it is imperative to find other effective therapies. Iron and calcium ions play key roles in oxidative stress, a hallmark of glaucoma. Therefore, we tested metal chelation by means of ethylenediaminetetraacetic acid (EDTA) combined with the permeability enhancer methyl sulfonyl methane (MSM) applied topically on the eye to determine if this non-invasive treatment is neuroprotective in rat optic nerve and retinal ganglion cells exposed to oxidative stress induced by elevated IOP. Hyaluronic acid (HA) was injected in the anterior chamber of the rat eye to elevate the IOP. EDTA-MSM was applied topically to the eye for 3 months. Eyeballs and optic nerves were processed for histological assessment of cytoarchitecture. Protein-lipid aldehyde adducts, and cyclooxygnease-2 (COX-2) were detected immunohistochemically. HA administration increased IOP and associated oxidative stress and inflammation. Elevated IOP was not affected by EDTA-MSM treatment. However oxidative damage and inflammation were ameliorated as reflected by decrease in formation of protein-lipid aldehyde adducts and COX-2 expression, respectively. Furthermore, EDTA-MSM treatment increased retinal ganglion cell survival and decreased demyelinization of optic nerve compared with untreated eyes. Chelation treatment with EDTA-MSM ameliorates sequelae of IOP-induced toxicity without affecting IOP. Since most current therapies aim at reducing IOP and damage occurs even in the absence of elevated IOP, EDTA-MSM has the potential to work in conjunction with pressure-reducing therapies to alleviate damage to the optic nerve and retinal ganglion cells. PMID:24509160

The Role of Endogenous Serotonin in Methamphetamine-Induced Neurotoxicity to Dopamine Nerve Endings of the Striatum

PubMed Central

Thomas, David M.; Angoa-Pérez, Mariana; Francescutti-Verbeem, Dina M.; Shah, Mrudang M.; Kuhn, Donald M.

2010-01-01

Methamphetamine (METH) is a neurotoxic drug of abuse that damages the dopamine (DA) neuronal system in a highly delimited manner. The brain structure most affected by METH is the striatum where long-term DA depletion and microglial activation are maximal. Endogenous DA has been implicated as a critical participant in METH-induced neurotoxicity, most likely as a substrate for non-enzymatic oxidation by METH-generated reactive oxygen species (ROS). The striatum is also extensively innervated by serotonin (5HT) nerve endings and this neurochemical system is modified by METH in much the same manner as seen in DA nerve endings (i.e., increased release of 5HT, loss of function in tryptophan hydroxylase and the serotonin transporter, long-term depletion of 5HT stores). 5HT can also be modified by ROS to form highly reactive species that damage neurons but its role in METH neurotoxicity has not been assessed. Increases in 5HT levels with 5HTP do not change METH-induced neurotoxicity to the DA nerve endings as revealed by reductions in DA, tyrosine hydroxylase and dopamine transporter levels. Partial reductions in 5HT with p-chlorophenylalanine (PCPA) are without effect on METH toxicity, despite the fact that PCPA largely prevents METH-induced hyperthermia. Mice lacking the gene for brain tryptophan hydroxylase 2 are devoid of brain 5HT and respond to METH in the same manner as wild-type controls, despite showing enhanced drug-induced hyperthermia. Taken together, the present results indicate that endogenous 5HT does not appear to play a role in METH-induced damage to DA nerve endings of the striatum. PMID:20722968

The role of endogenous serotonin in methamphetamine-induced neurotoxicity to dopamine nerve endings of the striatum.

PubMed

Thomas, David M; Angoa Pérez, Mariana; Francescutti-Verbeem, Dina M; Shah, Mrudang M; Kuhn, Donald M

2010-11-01

Methamphetamine (METH) is a neurotoxic drug of abuse that damages the dopamine (DA) neuronal system in a highly delimited manner. The brain structure most affected by METH is the striatum where long-term DA depletion and microglial activation are maximal. Endogenous DA has been implicated as a critical participant in METH-induced neurotoxicity, most likely as a substrate for non-enzymatic oxidation by METH-generated reactive oxygen species. The striatum is also extensively innervated by serotonin (5HT) nerve endings and this neurochemical system is modified by METH in much the same manner as seen in DA nerve endings (i.e., increased release of 5HT, loss of function in tryptophan hydroxylase and the serotonin transporter, long-term depletion of 5HT stores). 5HT can also be modified by reactive oxygen species to form highly reactive species that damage neurons but its role in METH neurotoxicity has not been assessed. Increases in 5HT levels with 5-hydroxytryptophan do not change METH-induced neurotoxicity to the DA nerve endings as revealed by reductions in DA, tyrosine hydroxylase and dopamine transporter levels. Partial reductions in 5HT with p-chlorophenylalanine are without effect on METH toxicity, despite the fact that p-chlorophenylalanine largely prevents METH-induced hyperthermia. Mice lacking the gene for brain tryptophan hydroxylase 2 are devoid of brain 5HT and respond to METH in the same manner as wild-type controls, despite showing enhanced drug-induced hyperthermia. Taken together, the present results indicate that endogenous 5HT does not appear to play a role in METH-induced damage to DA nerve endings of the striatum. © 2010 The Authors. Journal Compilation © 2010 International Society for Neurochemistry.

Involvement of peripheral III nerve in multiple sclerosis patient: Report of a new case and discussion of the underlying mechanism.

PubMed

Shor, Natalia; Amador, Maria Del Mar; Dormont, Didier; Lubetzki, Catherine; Bertrand, Anne

2017-04-01

Multiple sclerosis (MS) is a chronic disorder that affects the central nervous system myelin. However, a few radiological cases have documented an involvement of peripheral cranial nerves, within the subarachnoid space, in MS patients. We report the case of a 36-year-old female with a history of relapsing-remitting (RR) MS who consulted for a subacute complete paralysis of the right III nerve. Magnetic resonance imaging (MRI) examination showed enhancement and thickening of the cisternal right III nerve, in continuity with a linear, mesencephalic, acute demyelinating lesion. Radiological involvement of the cisternal part of III nerve has been reported only once in MS patients. Radiological involvement of the cisternal part of V nerve occurs more frequently, in almost 3% of MS patients. In both situations, the presence of a central demyelinating lesion, in continuity with the enhancement of the peripheral nerve, suggests that peripheral nerve damage is a secondary process, rather than a primary target of demyelination.

Lack of effectiveness of laser therapy applied to the nerve course and the correspondent medullary roots

PubMed Central

Sousa, Fausto Fernandes de Almeida; Ribeiro, Thaís Lopes; Fazan, Valéria Paula Sassoli; Barbieri, Claudio Henrique

2013-01-01

OBJECTIVE: To investigate the influence of low intensity laser irradiation on the regeneration of the fibular nerve of rats after crush injury. METHODS: Twenty-five rats were used, divided into three groups: 1) intact nerve, no treatment; 2) crushed nerve, no treatment; 3) crush injury, laser irradiation applied on the medullary region corresponding to the roots of the sciatic nerve and subsequently on the course of the damaged nerve. Laser irradiation was carried out for 14 consecutive days. RESULTS: Animals were evaluated by functional gait analysis with the peroneal functional index and by histomorphometric analysis using the total number of myelinated nerve fibers and their density, total number of Schwann cells, total number of blood vessels and the occupied area, minimum diameter of the fiber diameter and G-quotient. CONCLUSION: According to the statistical analysis there was no significant difference among groups and the authors conclude that low intensity laser irradiation has little or no influence on nerve regeneration and functional recovery. Laboratory investigation. PMID:24453650

Delivery of adipose-derived stem cells in poloxamer hydrogel improves peripheral nerve regeneration.

PubMed

Allbright, Kassandra O; Bliley, Jacqueline M; Havis, Emmanuelle; Kim, Deok-Yeol; Dibernardo, Gabriella A; Grybowski, Damian; Waldner, Matthias; James, Isaac B; Sivak, Wesley N; Rubin, J Peter; Marra, Kacey G

2018-02-06

Peripheral nerve damage is associated with high long-term morbidity. Because of beneficial secretome, immunomodulatory effects, and ease of clinical translation, transplantation with adipose-derived stem cells (ASC) represents a promising therapeutic modality. Effect of ASC delivery in poloxamer hydrogel was assessed in a rat sciatic nerve model of critical-sized (1.5 cm) peripheral nerve injury. Nerve/muscle unit regeneration was assessed via immunostaining explanted nerve, quantitative polymerase chain reaction (qPCR), and histological analysis of reinnervating gastrocnemius muscle. On the basis of viability data, 10% poloxamer hydrogel was selected for in vivo study. Six weeks after transection and repair, the group treated with poloxamer delivered ASCs demonstrated longest axonal regrowth. The qPCR results indicated that the inclusion of ASCs appeared to result in expression of factors that aid in reinnervating muscle tissue. Delivery of ASCs in poloxamer addresses multiple facets of the complexity of nerve/muscle unit regeneration, representing a promising avenue for further study. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

Effects of sciatic nerve stimulation on the propagation of cortical spreading depression

NASA Astrophysics Data System (ADS)

Sun, Xiaoli; Yu, Zhidong; Zeng, Shaoqun; Luo, Qingming; Li, Pengcheng

2008-02-01

Cortical spreading depression (CSD) is an important pathological model of migraine and is related to other neural disorders, such as cerebral ischemia and epilepsy. It has been reported that brain stimulation is a quite effective way to treat neural diseases. However, direct stimulation could cause harm to brain. If peripheral nerve stimulation could have the same treatment, it would be essential to investigate the mechanisms of peripheral nerve and the study of sciatic nerve stimulation would have profound clinical meaning. In this paper, we used optical intrinsic signal imaging (OISI) and extracellular electrophysiologic recording techniques to study the effects of sciatic nerve stimulation on the propagation of CSD. We found that: (1) continuous sciatic nerve stimulation on rats caused a decrease in light intensity on the whole cortex, which meant an increase in cerebral blood volume(CBV); (2) the spreading velocity of CSD declined from 3.63+/- 0.272 mm/min to 3.06+/-0.260 mm/min during sciatic nerve stimulation, compared with that without sciatic nerve stimulation. In summary, data suggests that sciatic nerve stimulation elicits a response of cortex and causes a slowdown in the propagation of CSD.

Bowman Break and Subbasal Nerve Plexus Changes in a Patient With Dry Eye Presenting With Chronic Ocular Pain and Vitamin D Deficiency.

PubMed

Shetty, Rohit; Deshpande, Kalyani; Deshmukh, Rashmi; Jayadev, Chaitra; Shroff, Rushad

2016-05-01

To report the case of a 40-year-old patient with persistent bilateral ocular pain and discomfort for 2 years in whom conventional management of dry eye had failed. Detailed ocular examination, meibography, and tear film evaluation were suggestive of bilateral meibomian gland dysfunction and evaporative dry eye. Topical medication failed to alleviate the patient's symptoms. To identify the cause of pain, imaging was performed with in vivo confocal microscopy and anterior segment spectral domain optical coherence tomography. Systemic evaluation revealed severe vitamin D deficiency with a value of 5.86 ng/mL. Case report. In vivo confocal microscopy showed abnormal subbasal nerve plexus morphology, increased dendritic cell density, and enlarged terminal nerve sprouts. A breach in the Bowman layer was detected in both eyes on spectral domain optical coherence tomography. Conventional management having failed, LipiFlow treatment (TearScience, Morrisville, NC) was performed and topical therapy with cyclosporine 0.05%, steroids, and lubricating eye drops was initiated with incomplete symptomatic relief. However, with parenteral therapy for vitamin D deficiency, there was a dramatic improvement in the patient's symptoms. Inflammation aggravated by vitamin D deficiency results in an altered epithelial profile, Bowman layer damage, recruitment of dendritic cells, and altered subbasal nerve plexus features in patients with chronic dry eye disease. These can serve as potential imaging markers for studying the underlying mechanisms in patients with dry eye disease with persisting symptoms despite aggressive conventional treatment.

Prevention of neurological injuries during mandibular third molar surgery: technical notes

PubMed Central

La Monaca, Gerardo; Vozza, Iole; Giardino, Rita; Annibali, Susanna; Pranno, Nicola; Cristalli, Maria Paola

2017-01-01

Summary Surgery to the mandibular third molar is common, and injuries to the inferior alveolar nerve and the lingual nerve are well-recognized complications of this procedure. The aim of these technical notes is to describe operative measures for reducing neurological complications during mandibular third molar surgery. The following procedure should be used to prevent damage to the inferior alveolar nerve: a well-designed mucoperiosteal flap, to obtain appropriate access to the surgical area; a conservative ostectomy on the distal and distal-lingual side; tooth sectioning, to facilitate its removal by decreasing the retention zones; tooth dislocation in the path of withdrawal imposed by the curvature of the root apex; and careful socket debridement, when the roots of the extracted tooth are in intimate contact with the mandibular canal. To prevent injury to the lingual nerve, it is important (I) to assess the integrity of the mandibular inner cortex and exclude the presence of fenestration, which could cause the dislocation of the tooth or its fragment into the sublingual or submandibular space; (II) to avoid inappropriate or excessive dislocation proceedings, in order to prevent lingual cortex fracture; (III) to perform horizontal mesial-distal crown sectioning of the lingually inclined tooth; (IV) to protect the lingual flap with a retractor showing the cortical ridge; and (V) to pass the suture not too apically and from the inner side in a buccal-lingual direction in the retromolar area. PMID:29299188

Amyloidosis: Insights from Proteomics.

PubMed

Dogan, Ahmet

2017-01-24

Amyloidoses are a spectrum of disorders caused by abnormal folding and extracellular deposition of proteins. The deposits lead to tissue damage and organ dysfunction, particularly in the heart, kidneys, and nerves. There are at least 30 different proteins that can cause amyloidosis. The clinical management depends entirely on the type of protein deposited, and thus on the underlying pathogenesis, and often requires high-risk therapeutic intervention. Application of mass spectrometry-based proteomic technologies for analysis of amyloid plaques has transformed the way amyloidosis is diagnosed and classified. Proteomic assays have been extensively used for clinical management of patients with amyloidosis, providing unprecedented diagnostic and biological information. They have shed light on the pathogenesis of different amyloid types and have led to identification of numerous new amyloid types, including ALECT2 amyloidosis, which is now recognized as one of the most common causes of systemic amyloidosis in North America.

Treatment of the first bite syndrome.

PubMed

Costales-Marcos, María; López Álvarez, Fernando; Fernández-Vañes, Laura; Gómez, Justo; Llorente, José Luis

First bite syndrome is a potential complication of surgery involving the infratemporal fossa, deep lobe of the parotid gland and parapharyngeal space. It is described as an acute and intense pain in the parotid region caused with the first bite of each meal. It is related to damage to sympathetic innervation of the parotid gland. Parasympathetic hyperactivation is believed to stimulate an exaggerated myoepithelial cell contraction causing pain. Usual analgesic treatments have poor results. Botulinum toxin type A causes parasympathetic nerve paralysis of the parotid gland and this fact would minimize salivation and decrease first bite syndrome. The aim of this study is to show the details of the technique and our outcomes in 5 patients treated with botulinum toxin type A. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Peripheral Neuropathy Due to Vitamin Deficiency, Toxins, and Medications

PubMed Central

Staff, Nathan P.; Windebank, Anthony J.

2014-01-01

Purpose of Review: Peripheral neuropathies secondary to vitamin deficiencies, medications, or toxins are frequently considered but can be difficult to definitively diagnose. Accurate diagnosis is important since these conditions are often treatable and preventable. This article reviews the key features of different types of neuropathies caused by these etiologies and provides a comprehensive list of specific agents that must be kept in mind. Recent Findings: While most agents that cause peripheral neuropathy have been known for years, newly developed medications that cause peripheral neuropathy are discussed. Summary: Peripheral nerves are susceptible to damage by a wide array of toxins, medications, and vitamin deficiencies. It is important to consider these etiologies when approaching patients with a variety of neuropathic presentations; additionally, etiologic clues may be provided by other systemic symptoms. While length-dependent sensorimotor axonal peripheral neuropathy is the most common presentation, several examples present in a subacute severe fashion, mimicking Guillain-Barré syndrome. PMID:25299283

Nonthermal ablation with microbubble-enhanced focused ultrasound close to the optic tract without affecting nerve function.

PubMed

McDannold, Nathan; Zhang, Yong-Zhi; Power, Chanikarn; Jolesz, Ferenc; Vykhodtseva, Natalia

2013-11-01

Tumors at the skull base are challenging for both resection and radiosurgery given the presence of critical adjacent structures, such as cranial nerves, blood vessels, and brainstem. Magnetic resonance imaging-guided thermal ablation via laser or other methods has been evaluated as a minimally invasive alternative to these techniques in the brain. Focused ultrasound (FUS) offers a noninvasive method of thermal ablation; however, skull heating limits currently available technology to ablation at regions distant from the skull bone. Here, the authors evaluated a method that circumvents this problem by combining the FUS exposures with injected microbubble-based ultrasound contrast agent. These microbubbles concentrate the ultrasound-induced effects on the vasculature, enabling an ablation method that does not cause significant heating of the brain or skull. In 29 rats, a 525-kHz FUS transducer was used to ablate tissue structures at the skull base that were centered on or adjacent to the optic tract or chiasm. Low-intensity, low-duty-cycle ultrasound exposures (sonications) were applied for 5 minutes after intravenous injection of an ultrasound contrast agent (Definity, Lantheus Medical Imaging Inc.). Using histological analysis and visual evoked potential (VEP) measurements, the authors determined whether structural or functional damage was induced in the optic tract or chiasm. Overall, while the sonications produced a well-defined lesion in the gray matter targets, the adjacent tract and chiasm had comparatively little or no damage. No significant changes (p > 0.05) were found in the magnitude or latency of the VEP recordings, either immediately after sonication or at later times up to 4 weeks after sonication, and no delayed effects were evident in the histological features of the optic nerve and retina. This technique, which selectively targets the intravascular microbubbles, appears to be a promising method of noninvasively producing sharply demarcated lesions in deep brain structures while preserving function in adjacent nerves. Because of low vascularity--and thus a low microbubble concentration--some large white matter tracts appear to have some natural resistance to this type of ablation compared with gray matter. While future work is needed to develop methods of monitoring the procedure and establishing its safety at deep brain targets, the technique does appear to be a potential solution that allows FUS ablation of deep brain targets while sparing adjacent nerve structures.

Nonthermal ablation with microbubble-enhanced focused ultrasound close to the optic tract without affecting nerve function

PubMed Central

McDannold, Nathan; Zhang, Yong-Zhi; Power, Chanikarn; Jolesz, Ferenc; Vykhodtseva, Natalia

2014-01-01

Object Tumors at the skull base are challenging for both resection and radiosurgery given the presence of critical adjacent structures, such as cranial nerves, blood vessels, and brainstem. Magnetic resonance imaging–guided thermal ablation via laser or other methods has been evaluated as a minimally invasive alternative to these techniques in the brain. Focused ultrasound (FUS) offers a noninvasive method of thermal ablation; however, skull heating limits currently available technology to ablation at regions distant from the skull bone. Here, the authors evaluated a method that circumvents this problem by combining the FUS exposures with injected microbubble-based ultrasound contrast agent. These microbubbles concentrate the ultrasound-induced effects on the vasculature, enabling an ablation method that does not cause significant heating of the brain or skull. Methods In 29 rats, a 525-kHz FUS transducer was used to ablate tissue structures at the skull base that were centered on or adjacent to the optic tract or chiasm. Low-intensity, low-duty-cycle ultrasound exposures (sonications) were applied for 5 minutes after intravenous injection of an ultrasound contrast agent (Definity, Lantheus Medical Imaging Inc.). Using histological analysis and visual evoked potential (VEP) measurements, the authors determined whether structural or functional damage was induced in the optic tract or chiasm. Results Overall, while the sonications produced a well-defined lesion in the gray matter targets, the adjacent tract and chiasm had comparatively little or no damage. No significant changes (p > 0.05) were found in the magnitude or latency of the VEP recordings, either immediately after sonication or at later times up to 4 weeks after sonication, and no delayed effects were evident in the histological features of the optic nerve and retina. Conclusions This technique, which selectively targets the intravascular microbubbles, appears to be a promising method of noninvasively producing sharply demarcated lesions in deep brain structures while preserving function in adjacent nerves. Because of low vascularity—and thus a low microbubble concentration—some large white matter tracts appear to have some natural resistance to this type of ablation compared with gray matter. While future work is needed to develop methods of monitoring the procedure and establishing its safety at deep brain targets, the technique does appear to be a potential solution that allows FUS ablation of deep brain targets while sparing adjacent nerve structures. PMID:24010975

Side Effects: Nerve Problems (Peripheral Neuropathy)

Cancer.gov

Nerve problems, such as peripheral neuropathy, can be caused by cancer treatment. Learn about signs and symptoms of nerve changes. Find out how to prevent or manage nerve problems during cancer treatment.

TRPA1 channel mediates organophosphate-induced delayed neuropathy

PubMed Central

Ding, Qiang; Fang, Sui; Chen, Xueqin; Wang, Youxin; Li, Jian; Tian, Fuyun; Xu, Xiang; Attali, Bernard; Xie, Xin; Gao, Zhaobing

2017-01-01

The organophosphate-induced delayed neuropathy (OPIDN), often leads to paresthesias, ataxia and paralysis, occurs in the late-stage of acute poisoning or after repeated exposures to organophosphate (OP) insecticides or nerve agents, and may contribute to the Gulf War Syndrome. The acute phase of OP poisoning is often attributed to acetylcholinesterase inhibition. However, the underlying mechanism for the delayed neuropathy remains unknown and no treatment is available. Here we demonstrate that TRPA1 channel (Transient receptor potential cation channel, member A1) mediates OPIDN. A variety of OPs, exemplified by malathion, activates TRPA1 but not other neuronal TRP channels. Malathion increases the intracellular calcium levels and upregulates the excitability of mouse dorsal root ganglion neurons in vitro. Mice with repeated exposures to malathion also develop local tissue nerve injuries and pain-related behaviors, which resembles OPIDN. Both the neuropathological changes and the nocifensive behaviors can be attenuated by treatment of TRPA1 antagonist HC030031 or abolished by knockout of Trpa1 gene. In the classic hens OPIDN model, malathion causes nerve injuries and ataxia to a similar level as the positive inducer tri-ortho-cresyl phosphate (TOCP), which also activates TRPA1 channel. Treatment with HC030031 reduces the damages caused by malathion or tri-ortho-cresyl phosphate. Duloxetine and Ketotifen, two commercially available drugs exhibiting TRPA1 inhibitory activity, show neuroprotective effects against OPIDN and might be used in emergency situations. The current study suggests TRPA1 is the major mediator of OPIDN and targeting TRPA1 is an effective way for the treatment of OPIDN. PMID:28894590

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

PubMed Central

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

2014-01-01

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. PMID:25083397

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

PubMed

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.

Acorus tatarinowii Schott extract protects PC12 cells from amyloid-beta induced neurotoxicity.

PubMed

An, Hong-Mei; Li, Guo-Wen; Lin, Chen; Gu, Chao; Jin, Miao; Sun, Wen-Xian; Qiu, Ming-Feng; Hu, Bing

2014-05-01

Amyloid-beta induced neurotoxicity has been identified as a major cause of Alzheimer's disease. Acorus tatarinowii Schott is one of the most frequently used Chinese herbs for Alzheimer's disease treatment. However, the effects of Acorus tatarinowii Schott on amyloid-beta mediated nerve cell damage remains unknown. In the present study, neuronal differentiated PC12 cells were used as a model to evaluate the effects of A. tatarinowii Schott extract (ATSE) against Abeta25-35 induced neurotoxicity. The results showed pretreatment with ATSE significantly protected PC12 cells from Abeta25-35 induced cell death, lactate dehydrogenase release, DNA damage, mitochondrial dysfunction and cytochrome c release from mitochondria. In addition, pretreatment with ATSE also significantly inhibited Abeta25-35 induced caspase-3 activation and reactive oxygen species generation in PC12 cells. These observations suggested that ATSE protects PC12 cells from amyloid-beta induced neurotoxicity.

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

PubMed

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.

The Sihler staining study of the infraorbital nerve and its clinical complication.

PubMed

Yang, Hun-Mu; Won, Sung-Yoon; Lee, Young-Il; Kim, Hee-Jin; Hu, Kyung-Seok

2014-11-01

The infraorbital nerve (ION) is a cardinal cutaneous nerve that provides general sensation to the mid face. Its twigs are vulnerable to iatrogenic damage during medical and dental manipulations. The aims of this study were to elucidate the distribution pattern of the ION and thus help to prevent nerve damage during medical procedures and to enable accurate prognostic evaluation where complications do occur. This was achieved by treating 7 human hemifaces with the Sihler modified staining protocol, which enables clear visualization of the course and distribution of nerves without the accidental displacement of these structures that can occur during classic dissection. The twigs of the ION can be classified into the usual 5 groups: inferior palpebral, innervating the lower eyelid in a fan-shaped area; external and internal nasal, reaching the nosewing and philtrum including the septal area between the nostrils, respectively; as well as medial and lateral superior labial, supplying the superior labial area from the midline to the mouth corner. Of particular note, the superior labial twigs fully innervated the infraorbital triangle formed by the infraorbital foramen, the most lateral point of the nosewing, and the mouth corner. In the superior 3-quarter area, the ION twigs made anastomoses with the buccal branches of the facial nerve, forming an infraorbital nervous plexus. The infraorbital triangle may be considered a dangerous zone with respect to the risk for iatrogenic complications associated with the various medical interventions such as implant placement.

Brain plasticity after implanted peroneal nerve electrical stimulation to improve gait in chronic stroke patients: Two case reports.

PubMed

Thibaut, Aurore; Moissenet, Florent; Di Perri, Carol; Schreiber, Céline; Remacle, Angélique; Kolanowski, Elisabeth; Chantraine, Frédéric; Bernard, Claire; Hustinx, Roland; Tshibanda, Jean-Flory; Filipetti, Paul; Laureys, Steven; Gosseries, Olivia

2017-01-01

Recent studies have shown that stimulation of the peroneal nerve using an implantable 4-channel peroneal nerve stimulator could improve gait in stroke patients. To assess structural cortical and regional cerebral metabolism changes associated with an implanted peroneal nerve electrical stimulator to correct foot drop related to a central nervous system lesion. Two stroke patients presenting a foot drop related to a central nervous system lesion were implanted with an implanted peroneal nerve electrical stimulator. Both patients underwent clinical evaluations before implantation and one year after the activation of the stimulator. Structural magnetic resonance imaging (MRI) and [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) were acquired before and one year after the activation of the stimulator. Foot drop was corrected for both patients after the implantation of the stimulator. After one year of treatment, patient 1 improved in three major clinical tests, while patient 2 only improved in one test. Prior to treatment, FDG-PET showed a significant hypometabolism in premotor, primary and supplementary motor areas in both patients as compared to controls, with patient 2 presenting more widespread hypometabolism. One year after the activation of the stimulator, both patients showed significantly less hypometabolism in the damaged motor cortex. No difference was observed on the structural MRI. Clinical improvement of gait under peroneal nerve electrical stimulation in chronic stroke patients presenting foot drop was paralleled to metabolic changes in the damaged motor cortex.

Chronic dysphagia and trigeminal anesthesia after trichloroethylene exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence, W.H.; Partyka, E.K.

1981-12-01

A patient is described who inhaled trichloroethylene fumes while working in a closed underground pit. At the time of exposure he developed dysphagia, dysarthria and dyspnea. Assessment of his condition 11 years after the incident indicated major damage of cranial nerves, particularly the trigeminal, chronic involvement of the bulbar cranial nerves, and resultant esophageal and pharnygeal motility impairment. (JMT)

Inferior alveolar nerve cutting; legal liability versus desired patient outcomes.

PubMed

Kim, Soung Min; Lee, Jong Ho

2017-10-01

Mandibular angle reduction or reduction genioplasty is a routine well-known facial contouring surgery that reduces the width of the lower face resulting in an oval shaped face. During the intraoral resection of the mandibular angle or chin using an oscillating saw, unexpected peripheral nerve damage including inferior alveolar nerve (IAN) damage could occur. This study analyzed cases of damaged IANs during facial contouring surgery, and asked what the basic standard of care in these medical litigation-involved cases should be. We retrospectively reviewed a total of 28 patients with IAN damage after mandibular contouring from August 2008 to July 2015. Most of the patients did not have an antipathy to medical staff because they wanted their faces to be ovoid shaped. We summarized three representative cases according to each patient's perceptions and different operation procedures under the approvement by the Institutional Review Board of Seoul National University. Most of the patients did not want to receive any further operations not due to fear of an operation but because of the changes in their facial appearance. Thus, their fear may be due to a desire for a better perfect outcome, and to avoid unsolicited patient complaints related litigation. This article analyzed representative IAN cutting cases that occurred during mandibular contouring esthetic surgery and evaluated a questionnaire on the standard of care for the desired patient outcomes and the specialized surgeon's position with respect to legal liability.

Is endodontic treatment necessary during coronectomy procedure?

PubMed

Sencimen, Metin; Ortakoglu, Kerim; Aydin, Cumhur; Aydintug, Yavuz S; Ozyigit, Aykut; Ozen, Tuncer; Gunaydin, Yilmaz

2010-10-01

Close proximity of the inferior alveolar nerve (IAN) to the third molar roots can result in nerve injuries during extraction of third molars. Consequently, it is necessary to determine the relationship of the nerve and roots to avoid damage to the IAN. Computed tomography scans are widely used to determine the correct relationship between the IAN and lower third molars. The study consisted of 10 patients with 16 lower third molars in close relationship with the IAN who were divided into a study group and a control group. The patients in the study group were treated via coronectomies performed with endodontic treatments. The patients in the control group underwent coronectomies without endodontic treatment. The patients were followed up for at least 1 year. We had to extract 7 of the roots because of the infection in 8 patients belonging to the study group, which were treated endodontically. Moreover, there were 3 cases of IAN damage because of the extraction in the study group. However, in the control group, no infection was determined and IAN damage was absent. Coronectomy appears to be a reliable technique to protect the IAN from damage. This procedure has a low incidence of complications. Endodontic treatment does not affect the success of this method according to our results. Copyright © 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Electrophysiological examination and high frequency ultrasonography for diagnosis of radial nerve torsion and compression

PubMed Central

Shi, Miao; Qi, Hengtao; Ding, Hongyu; Chen, Feng; Xin, Zhaoqin; Zhao, Qinghua; Guan, Shibing; Shi, Hao

2018-01-01

Abstract This study aims to evaluate the value of electrophysiological examination and high frequency ultrasonography in the differential diagnosis of radial nerve torsion and radial nerve compression. Patients with radial nerve torsion (n = 14) and radial nerve compression (n = 14) were enrolled. The results of neurophysiological and high frequency ultrasonography were compared. Electrophysiological examination and high-frequency ultrasonography had a high diagnostic rate for both diseases with consistent results. Of the 28 patients, 23 were positive for electrophysiological examination, showing decreased amplitude and decreased conduction velocity of radial nerve; however, electrophysiological examination cannot distinguish torsion from compression. A total of 27 cases showed positive in ultrasound examinations among all 28 cases. On ultrasound images, the nerve was thinned at torsion site whereas thickened at the distal ends of torsion. The diameter and cross-sectional area of torsion or compression determined the nerve damage, and ultrasound could locate the nerve injury site and measure the length of the nerve. Electrophysiological examination and high-frequency ultrasonography can diagnose radial neuropathy, with electrophysiological examination reflecting the neurological function, and high-frequency ultrasound differentiating nerve torsion from compression. PMID:29480857

Effect of simvastatin on sensorial, motor, and morphological parameters in sciatic nerve crush induced-neuropathic pain in rats.

PubMed

Corso, Claudia Rita; Martins, Daniel Fernandes; Borges, Stephanie Carvalho; Beltrame, Olair Carlos; Telles, José Ederaldo Queiroz; Buttow, Nilza Cristina; Werner, Maria Fernanda de Paula

2018-06-01

The present study compares the effects of a low and high doses of simvastatin in a model of peripheral neuropathy by evaluating sensorial, motor, and morphological parameters. First, male Wistar rats were orally treated with vehicle (saline, 1 mL/kg), simvastatin (2 and 80 mg/kg) or morphine (2 mg/kg, s.c.), 1 h before 2.5% formalin injection. Neuropathic pain was induced by crushing the sciatic nerve, and mechanical and cold allodynia, nerve function, histology, MPO and NAG concentrations, as well as mevalonate induced-nociception were evaluated. Animals were orally treated with vehicle, simvastatin, or gabapentin (30 mg/kg) for 18 days. Simvastatin (2 and 80 mg/kg) reduced the inflammatory pain induced by formalin, but failed to decrease the paw edema. Mechanical allodynia was reduced by the simvastatin (2 mg/kg) until the 12th day after injury and until the 18th day by gabapentin. However, both simvastatin and gabapentin treatments failed in attenuated cold allodynia or improved motor function. Interestingly, both doses of simvastatin showed a neuroprotective effect and inhibited MPO activity without altering kidney and hepatic parameters. Additionally, only the higher dose of simvastatin reduced the cholesterol levels and the nociception induced by mevalonate. Our results reinforce the antinociceptive, antiallodynic, and anti-inflammatory effects of oral simvastatin administration, which can strongly contribute to the sciatic nerve morphology preservation. Furthermore, our data suggest that lower and higher doses of simvastatin present beneficial effects that are dependent and independent of the mevalonate pathway, respectively, without causing signs of nerve damage.

Optical coherence tomography guided dental drill

DOEpatents

DaSilva, Luiz B.; Colston, Jr., Bill W.; James, Dale L.

2002-01-01

A dental drill that has one or multiple single mode fibers that can be used to image in the vicinity of the drill tip. It is valuable to image below the surface being drilled to minimize damage to vital or normal tissue. Identifying the boundary between decayed and normal enamel (or dentine) would reduce the removal of viable tissue, and identifying the nerve before getting too close with the drill could prevent nerve damage. By surrounding a drill with several optical fibers that can be used by an optical coherence domain reflectometry (OCDR) to image several millimeters ahead of the ablation surface will lead to a new and improved dental treatment device.

A morphological and biochemical evaluation of the effects of quercetin on experimental sciatic nerve damage in rats.

PubMed

Türedi, Sibel; Yuluğ, Esin; Alver, Ahmet; Bodur, Akin; İnce, İmran

2018-04-01

The present study evaluated the neuroprotective and antioxidant effects of quercetin in a rat model of sciatic nerve crush injury using histopathological, morphometric and biochemical methods. A total of 48 male Sprague Dawley rats, aged 10-12 weeks old were randomly divided into eight groups, consisting of two sham groups (S-7, S-28), three quercetin-treated groups (Q-7, Q-28; 200 mg/kg/7 days), trauma (T-7, T-28; 1 min sciatic nerve crush injury) and three trauma+quercetin groups (T+Q-7, T+Q-28; trauma+quercetin 200 mg/kg/7 days). Rats were sacrificed on day 7 or 28. Oxidant-antioxidant biochemical parameters in nerve tissues from all groups were analyzed using histopathological staining with toluidine blue and Masson's trichrome. DNA fragmentations were identified using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling in cells from each tissue sample. Degeneration of the axons and myelin sheath, the breakdown of the concentric lamellar structure of the myelin sheath and axonal swelling were observed in groups T-7 and T-28. Myelin sheath thicknesses, nerve fiber diameters and the number of myelinated nerve fibers decreased, while the apoptotic index (AI) increased in the T-7 and T-28 groups. However, it was observed that nerve regeneration began in the T+Q-7 and T+Q-28 groups compared with the sham groups, together with the healing of cellular damage and axonal structure and a decrease in the AI. Malondialdehyde and superoxide dismutase activity did not differ significantly between the T-7 and S-7 groups. However, catalase activity significantly decreased in the T-28 group when compared with the sham 7 day group. Tissue malondialdehyde levels significantly increased, while serum catalase activity increased in the T+Q-7 group compared with the T-7 group. These results suggest that quercetin has beneficial effects on nerve regeneration and may shorten the healing period in crush-type sciatic nerve injuries.

A silk sericin/silicone nerve guidance conduit promotes regeneration of a transected sciatic nerve.

PubMed

Xie, Hongjian; Yang, Wen; Chen, Jianghai; Zhang, Jinxiang; Lu, Xiaochen; Zhao, Xiaobo; Huang, Kun; Li, Huili; Chang, Panpan; Wang, Zheng; Wang, Lin

2015-10-28

Peripheral nerve gap defects lead to significant loss of sensory or motor function. Tissue engineering has become an important alternative to nerve repair. Sericin, a major component of silk, is a natural protein whose value in tissue engineering has just begun to be explored. Here, the first time use of sericin in vivo is reported as a long-term implant for peripheral nerve regeneration. A sericin nerve guidance conduit is designed and fabricated. This conduit is highly porous with mechanical strength matching peripheral nerve tissue. It supports Schwann cell proliferation and is capable of up-regulating the transcription of glial cell derived neurotrophic factor and nerve growth factor in Schwann cells. The sericin conduit wrapped with a silicone conduit (sericin/silicone double conduits) is used for bridging repair of a 5 mm gap in a rat sciatic nerve transection model. The sericin/silicone double conduits achieve functional recovery comparable to that of autologous nerve grafting as evidenced by drastically improved nerve function and morphology. Importantly, this improvement is mainly attributed to the sericin conduit as the silicone conduit alone only produces marginal functional recovery. This sericin/silicone-double-conduit strategy offers an efficient and valuable alternative to autologous nerve grafting for repairing damaged peripheral nerve. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Neuro-immune lessons from an annelid: The medicinal leech.

PubMed

Tasiemski, Aurélie; Salzet, Michel

2017-01-01

An important question that remains unanswered is how the vertebrate neuroimmune system can be both friend and foe to the damaged nervous tissue. Some of the difficulty in obtaining responses in mammals probably lies in the conflation in the central nervous system (CNS), of the innate and adaptive immune responses, which makes the vertebrate neuroimmune response quite complex and difficult to dissect. An alternative strategy for understanding the relation between neural immunity and neural repair is to study an animal devoid of adaptive immunity and whose CNS is well described and regeneration competent. The medicinal leech offers such opportunity. If the nerve cord of this annelid is crushed or partially cut, axons grow across the lesion and conduction of signals through the damaged region is restored within a few days, even when the nerve cord is removed from the animal and maintained in culture. When the mammalian spinal cord is injured, regeneration of normal connections is more or less successful and implies multiple events that still remain difficult to resolve. Interestingly, the regenerative process of the leech lesioned nerve cord is even more successful under septic than under sterile conditions suggesting that a controlled initiation of an infectious response may be a critical event for the regeneration of normal CNS functions in the leech. Here are reviewed and discussed data explaining how the leech nerve cord sensu stricto (i.e. excluding microglia and infiltrated blood cells) recognizes and responds to microbes and mechanical damages. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

PubMed

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.

The trigeminal trophic syndrome: an unusual cause of nasal ulceration.

PubMed

Monrad, Seetha U; Terrell, Jeffrey E; Aronoff, David M

2004-06-01

Trigeminal trophic syndrome (TTS) is an unusual complication after peripheral or central damage to the trigeminal nerve, characterized by anesthesia, paresthesias, and ala nasi ulceration. We describe a patient with classic TTS after trigeminal rhizotomy who underwent several extensive evaluations for nasal ulceration and received prolonged immunosuppressive therapy for a presumed autoimmune disorder before the correct diagnosis was made. An understanding of the predisposing factors and clinical presentation of TTS is important to ensure a timely diagnosis of this difficult-to-treat illness. Differentiation of TTS from malignancy, infection, or vasculitis is possible on the basis of clinical history, tissue biopsy, and serologic evaluation.

"Doomed to go in company with miserable pain": surgical recognition and treatment of amputation-related pain on the Western Front during World War 1.

PubMed

Edwards, Dafydd S; Mayhew, Emily R; Rice, Andrew S C

2014-11-08

The principal feature of injuries from World War 1 was musculoskeletal trauma and injury to peripheral nerves as a result of damage to the upper and lower limbs caused by gunshot wounds and fragments of artillery munitions. Amputation was used as a treatment in field hospitals to save lives; limb conservation was a secondary consideration. A century later, the principal feature of injuries to soldiers in today's wars in Iraq and Afghanistan is also musculoskeletal trauma and injury to the peripheral nerves caused by improvised explosive devices. Common to both types of injury is postamputation pain. We searched The Lancet's archives in this Series paper to show the efforts of surgeons in World War 1 to understand and treat postamputation pain in its own right both during and immediately after the war. Despite unprecedented patient numbers and levels of civilian medical expertise, little progress was made in providing relief from this type of pain, a grave concern to the surgeons treating these soldiers. Today postamputation pain is understood beyond a surgical context but remains a complex and poorly understood condition with few effective treatments. Copyright © 2014 Elsevier Ltd. All rights reserved.

In vivo soft tissue differentiation by diffuse reflectance spectroscopy: preliminary results

NASA Astrophysics Data System (ADS)

Zam, Azhar; Stelzle, Florian; Tangermann-Gerk, Katja; Adler, Werner; Nkenke, Emeka; Neukam, Friedrich Wilhelm; Schmidt, Michael; Douplik, Alexandre

Remote laser surgery does not provide haptic feedback to operate layer by layer and preserve vulnerable anatomical structures like nerve tissue or blood vessels. The aim of this study is identification of soft tissue in vivo by diffuse reflectance spectroscopy to set the base for a feedback control system to enhance nerve preservation in oral and maxillofacial laser surgery. Various soft tissues can be identified by diffuse reflectance spectroscopy in vivo. The results may set the base for a feedback system to prevent nerve damage during oral and maxillofacial laser surgery.

Hypothesis on two different functionalities co-existing in frontal lobe of human brains.

PubMed

Wang, Jue

2013-09-01

Human frontal lobe is a key area from where our cognition, memory and emotion display or function. In medical case study, there are patients with social dysfunctions, lack of passion or emotion as result of their frontal lobe damage caused by pathological changes, traumatic damage, and brain tumor remove operations. The syndrome of frontal lobe damage remains at large unanswered medically. From early stage of pregnancy, there exists lobe layers, nerve combine, and neurons synaptic, indicating a completion of growth of functionality inside frontal lobe. However, this completion of growth does not match the growth of human intelligence. Human infants only start and complete their cognition and memory functionality one full year after their birth which is marked by huge amount of neurons synaptic inside their frontal lobe, which is not part of a continual growth of originally developed functions. By reasoning on pathological changes of frontal lobe, a hypothesis was established that two individually functional mechanisms co-existed inside one frontal lobe. This neuron system is particularly for human beings. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pathophysiology of primary open-angle glaucoma from a neuroinflammatory and neurotoxicity perspective: a review of the literature.

PubMed

Evangelho, Karine; Mogilevskaya, Maria; Losada-Barragan, Monica; Vargas-Sanchez, Jeinny Karina

2017-12-30

Glaucoma is the leading cause of blindness in humans, affecting 2% of the population. This disorder can be classified into various types including primary, secondary, glaucoma with angle closure and with open angle. The prevalence of distinct types of glaucoma differs for each particular region of the world. One of the most common types of this disease is primary open-angle glaucoma (POAG), which is a complex inherited disorder characterized by progressive retinal ganglion cell death, optic nerve head excavation and visual field loss. Nowadays, POAG is considered an optic neuropathy, while intraocular pressure is proposed to play a fundamental role in its pathophysiology and especially in optic disk damage. However, the exact mechanism of optic nerve head damage remains a topic of debate. This literature review aims to bring together the information on the pathophysiology of primary open-angle glaucoma, particularly focusing on neuroinflammatory mechanisms leading to the death of the retinal ganglion cell. A literature search was done on PubMed using key words including primary open-angle glaucoma, retinal ganglion cells, Müller cells, glutamate, glial cells, ischemia, hypoxia, exitotoxicity, neuroinflammation, axotomy and neurotrophic factors. The literature was reviewed to collect the information published about the pathophysiologic mechanisms of RGC death in the POAG, from a neuroinflammatory and neurotoxicity perspective. Proposed mechanisms for glaucomatous damage are a result of pressure in RGC followed by ischemia, hypoxia of the ONH, and consequently death due to glutamate-induced excitotoxicity, deprivation of energy and oxygen, increase in levels of inflammatory mediators and alteration of trophic factors flow. These events lead to blockage of anterograde and retrograde axonal transport with ensuing axotomy and eventually blindness. The damage to ganglion cells and eventually glaucomatous injury can occur via various mechanisms including baric trauma, ischemia and impact of metabolic toxins, which triggers an inflammatory process and secondary degeneration in the ONH.

Nerve Entrapment in Ankle and Foot: Ultrasound Imaging.

PubMed

Chari, Basavaraj; McNally, Eugene

2018-07-01

Peripheral nerve entrapment of the ankle and foot is relatively uncommon and often underdiagnosed because electrophysiologic studies may not contribute to the diagnosis. Anatomy of the peripheral nerves is variable and complex, and along with a comprehensive physical examination, a thorough understanding of the applied anatomy is essential. Several studies have helped identify specific areas in which nerves are commonly compressed. Identified secondary causes of nerve compression include previous trauma, osteophytes, ganglion cysts, edema, accessory muscles, tenosynovitis, vascular lesions, and a primary nerve tumor. Imaging plays a key role in identifying primary and secondary causes of nerve entrapment, specifically ultrasound (US) and magnetic resonance imaging. US is a dynamic imaging modality that is cost effective and offers excellent resolution. Symptoms of nerve entrapment may mimic other common foot and ankle conditions such as plantar fasciitis. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Determination of functional and morphologic changes in palmar digital nerves after nonfocused extracorporeal shock wave treatment in horses.

PubMed

Bolt, David M; Burba, Daniel J; Hubert, Jeremy D; Strain, George M; Hosgood, Giselle L; Henk, William G; Cho, Doo-Youn

2004-12-01

To determine functional and morphologic changes in palmar digital nerves after nonfocused extracorporeal shock wave (ESW) treatment in horses. 6 horses. The medial and lateral palmar digital nerves of the left forelimb were treated with nonfocused ESWs. The medial palmar digital nerve of the right forelimb served as a nontreated control nerve. At 3, 7, and 35 days after treatment, respectively, 2 horses each were anesthetized and nerves were surgically exposed. Sensory nerve conduction velocities (SNCVs) of treated and control nerves were recorded, after which palmar digital neurectomies were performed. Morphologic changes in nerves were assessed via transmission electron microscopy. Significantly lower SNCV in treated medial and lateral nerves, compared with control nerves, was found 3 and 7 days after treatment. A significantly lower SNCV was detected in treated medial but not lateral nerves 35 days after treatment. Transmission electron microscopy of treated nerves revealed disruption of the myelin sheath with no evidence of damage to Schwann cell bodies or axons, 3, 7, and 35 days after treatment. Nonfocused ESW treatment of the metacarpophalangeal area resulted in lower SNCV in palmar digital nerves. This effect likely contributes to the post-treatment analgesia observed in horses and may result in altered peripheral pain perception. Horses with preexisting lesions may be at greater risk of sustaining catastrophic injuries when exercised after treatment.

A nerve guidance conduit with topographical and biochemical cues: potential application using human neural stem cells

NASA Astrophysics Data System (ADS)

Jenkins, Phillip M.; Laughter, Melissa R.; Lee, David J.; Lee, Young M.; Freed, Curt R.; Park, Daewon

2015-06-01

Despite major advances in the pathophysiological understanding of peripheral nerve damage, the treatment of nerve injuries still remains an unmet medical need. Nerve guidance conduits present a promising treatment option by providing a growth-permissive environment that 1) promotes neuronal cell survival and axon growth and 2) directs axonal extension. To this end, we designed an electrospun nerve guidance conduit using a blend of polyurea and poly-caprolactone with both biochemical and topographical cues. Biochemical cues were integrated into the conduit by functionalizing the polyurea with RGD to improve cell attachment. Topographical cues that resemble natural nerve tissue were incorporated by introducing intraluminal microchannels aligned with nanofibers. We determined that electrospinning the polymer solution across a two electrode system with dissolvable sucrose fibers produced a polymer conduit with the appropriate biomimetic properties. Human neural stem cells were cultured on the conduit to evaluate its ability to promote neuronal growth and axonal extension. The nerve guidance conduit was shown to enhance cell survival, migration, and guide neurite extension.

Hypoglossal-facial nerve reconstruction using a Y-tube-conduit reduces aberrant synkinetic movements of the orbicularis oculi and vibrissal muscles in rats.

PubMed

Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N; Sarikcioglu, Levent

2014-01-01

The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone.

Hypoglossal-Facial Nerve Reconstruction Using a Y-Tube-Conduit Reduces Aberrant Synkinetic Movements of the Orbicularis Oculi and Vibrissal Muscles in Rats

PubMed Central

Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N.; Sarikcioglu, Levent

2014-01-01

The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone. PMID:25574468

Chronic Constriction Injury of the Infraorbital Nerve in the Rat using modified syringe needle

PubMed Central

Kernisant, Melanie; Gear, Robert; Jasmin, Luc; Vit, Jean-Philippe; Ohara, Peter T.

2008-01-01

Here we report a method for performing a chronic constriction injury (CCI) of the infraorbital nerve (ION) in the rat as a component of a chronic pain model. The surgical approach to the ION is described together with the use of a modified dental syringe needle that simplifies placing two chromic gut ligatures around the ION. This method makes the surgical procedure easier, the nerve injury more consistent across animals and reduces secondary damage to the ION and surrounding tissue. Pain behavior testing together with immunostaining for markers of nerve injury in the spinal trigeminal nucleus show the suitability of this procedure as a model of orofacial pain. PMID:18501433

Effects of histidine and n-acetylcysteine on experimental lesions induced by doxorubicin in sciatic nerve of rats.

PubMed

Farshid, Amir Abbas; Tamaddonfard, Esmaeal; Najafi, Sima

2015-10-01

In this study, the effect of separate and combined intraperitoneal (i.p.) injections of histidine and n-acetylcysteine were investigated on experimental damage induced by doxorubicin (DOX) in sciatic nerve of rats. DOX was i.p. injected at a dose of 4 mg/kg once weekly for four weeks. Histidine and n-acetylcysteine were i.p. injected at a same dose of 20 mg/kg. Cold and mechanical allodynia were recorded using acetone spray and von Frey filaments tests, respectively. The sciatic nerve damage was evaluated by light microscopy. Plasma levels of malondialdehyde (MDA) and total antioxidant capacity (TAC) were measured. Histidine and especially n-acetylcysteine at a same dose of 20 mg/kg suppressed cold and mechanical allodynia, improved sciatic nerve lesions and reversed MDA and TAC levels in DOX-treated groups. Combination treatment with histidine and n-acetylcysteine showed better responses when compared with them used alone. The results of the present study showed peripheral neuroprotective effects for histidine and n-acetylcysteine. Reduction of free radical-induced toxic effects may have a role in neuroprotective properties of histidine and n-acetylcysteine.

BOTULISM. STUDIES ON THE MANNER IN WHICH THE TOXIN OF CLOSTRIDIUM BOTULINUM ACTS UPON THE BODY

PubMed Central

Dickson, Ernest C.; Shevky, Richard

1923-01-01

A survey of the results of these experiments shows, we believe conclusively, that in botulinus intoxication in cats, dogs, and rabbits there is a specific effect upon the portions of the autonomic nervous system which Gaskell (14) described as the bulbosacral and prosomatic outflows of connector fibers respectively, which results in a blocking of the nerve impulses of these nerves. The experimental as well as the clinical evidence indicates that there is no damage to the nerves of the thoracicolumbar outflow. The exact location of the damage has not been ascertained nor has the mechanism by which the nerve impulse is blocked been determined. The experiments show, however, that the lesions in these portions of the nervous system are not of central distribution but are peripheral, and that the block cannot be due to an organic break in the conduction apparatus but must be due to some derangement which is relatively unstable. If it were otherwise it would not be possible to induce a physiological response even by massive stimulation, nor could the response be subsequently repeated by stimuli which lie within the limits of normal intensity. The application of the results of these experiments to the clinical manifestations of botulism will be discussed in a later report after the effect of the toxin upon the skeletal motor nerves has been described. PMID:19868755

Study on the deformations of the lamina cribrosa during glaucoma.

PubMed

Tian, Hanjing; Li, Long; Song, Fan

2017-06-01

The lamina cribrosa is the primary site of optic nerve injury during glaucoma, and its deformations induced by elevated intraocular pressure are associated directly with the optic nerve injury and visual field defect. However, the deformations in a living body have been poorly understood yet so far. It is because that integral observation and precise measurement of the deformations in vivo are now almost impossible in the clinical diagnosis and treatment of glaucoma. In the present study, a new mechanical model of the lamina cribrosa is presented by using Reissner's thin plate theory. This model accurately displays the stress and deformation states in the lamina cribrosa under elevated intraocular pressure, in which the shear deformation is not presented by the previous models, however, is demonstrated to play a key role in the optic nerve injury. Further, the deformations of the structures, involving the optic nerve channels and the laminar sheets in the lamina cribrosa, are first investigated in detail. For example, the dislocation of the laminar sheets reaches 18.6μm under the intraocular pressure of 40mmHg, which is large enough to damage the optic nerve axons. The results here confirm some previously proposed clinical speculations on the deformations of the pore shape in the lamina cribrosa under elevated intraocular pressure during glaucoma. Finally, some essentially clinical questions existed during glaucoma, such as the pathological mechanism of the open-angle glaucoma with normal intraocular pressure, are discussed. The present study is beneficial to deeply understanding the optic nerve injury during glaucoma. The lamina cribrosa is the primary site of the optic nerve injury induced by elevated intraocular pressure during glaucoma. Under high intraocular pressure, the optic nerve channel near to the periphery of the lamina cribrosa (Channel A) is deformed to become into a tortuous elliptical horn from a straight cylinder, while the optic nerve channel near to the center of the lamina cribrosa (Channel B) is deformed to become into a straight horn from a straight cylinder. These deformations cause both the axoplasm flow obstacle in the axon fibers and the blocked blood flow in the capillaries which pass through the channels, and trigger the visual field defect during glaucoma. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

A case of bilateral lower cranial nerve palsies after base of skull trauma with complex management issues: case report and review of the literature.

PubMed

Lehn, Alexander Christoph; Lettieri, Jennie; Grimley, Rohan

2012-05-01

Fractures of the skull base can cause lower cranial nerve palsies because of involvement of the nerves as they traverse the skull. A variety of syndromes have been described, often involving multiple nerves. These are most commonly unilateral, and only a handful of cases of bilateral cranial nerve involvement have been reported. We describe a 64-year-old man with occipital condylar fracture complicated by bilateral palsies of IX and X nerves associated with dramatic physiological derangement causing severe management challenges. Apart from debilitating postural hypotension, he developed dysphagia, severe gastrointestinal dysmotility, issues with airway protection as well as airway obstruction, increased oropharyngeal secretions and variable respiratory control. This is the first report of a patient with traumatic bilateral cranial nerve IX and X nerve palsies. This detailed report and the summary of all 6 previous case reports of traumatic bilateral lower cranial nerve palsies illustrate clinical features, treatment strategies, and outcomes of these rare events.

Optical stimulation of the prostate nerves: A potential diagnostic technique

NASA Astrophysics Data System (ADS)

Tozburun, Serhat

There is wide variability in sexual potency rates (9--86%) after nerve-sparing prostate cancer surgery due to limited knowledge of the location of the cavernous nerves (CN's) on the prostate surface, which are responsible for erectile function. Thus, preservation of the CN's is critical in preserving a man's ability to have spontaneous erections following surgery. Nerve-mapping devices, utilizing conventional Electrical Nerve Stimulation (ENS) techniques, have been used as intra-operative diagnostic tools to assist in preservation of the CN. However, these technologies have proven inconsistent and unreliable in identifying the CN's due to the need for physical contact, the lack of spatial selectivity, and the presence of electrical artifacts in measurements. Optical Nerve Stimulation (ONS), using pulsed infrared laser radiation, is studied as an alternative to ENS. The objective of this study is sevenfold: (1) to develop a laparoscopic laser probe for ONS of the CN's in a rat model, in vivo; (2) to demonstrate faster ONS using continuous-wave infrared laser radiation; (3) to describe and characterize the mechanism of successful ONS using alternative laser wavelengths; (4) to test a compact, inexpensive all-single-mode fiber configuration for optical stimulation of the rat CN studies; (5) to implement fiber optic beam shaping methods for comparison of Gaussian and flat-top spatial beam profiles during ONS; (6) to demonstrate successful ONS of CN's through a thin layer of fascia placed over the nerve and prostate gland; and (7) to verify the experimentally determined therapeutic window for safe and reliable ONS without thermal damage to the CN's by comparison with a computational model for thermal damage. A 5.5-Watt Thulium fiber laser operated at 1870 nm and two pigtailed, single mode, near-IR diode lasers (150-mW, 1455-nm laser and 500-mW, 1550-nm laser) were used for non-contact stimulation of the rat CN's. Successful laser stimulation, as measured by an intracavernous pressure (ICP) response in the penis, was achieved with the laser operating in CW mode. CW optical nerve stimulation provides a significantly faster ICP response time using a lower laser power laser than conventional pulsed stimulation. An all-single-mode fiber design was successfully tested in a rat model. The CN reached a threshold temperature of ˜ 42 °C, with response times as short as 3 s, and ICP responses in the rat penis of up to 50 mmHg compared to a baseline of 5--10 mmHg. Chemical etching of the distal single-mode-fiber tip produced a concave shape and transformed the Gaussian to a flat-top spatial beam profile, resulting in simplified alignment of the laser beam with the nerve. This novel, all-single-mode-fiber laser nerve stimulation system introduces several advantages including: (1) a less expensive and more compact ONS configuration; (2) elimination of alignment and cleaning bulk optical components; and (3) improved spatial beam profile for simplified alignment. For the fascia layers over the CN's (240--600 microm), the 1550 nm laser with an optical penetration depth of ˜ 930 microm in water was substituted for the 1455 nm laser. Successful ONS was achieved, for the first time, in fascia layers up to 450 microm thick which is critical for future clinical translation of this method for intra-operative identification and preservation of CN's during prostate cancer surgery. In order to define the upper limit of the therapeutic window for ONS of CN in a rat model, in vivo, identification of the thermal damage threshold for the CN after laser irradiation was investigated by direct comparison of the visible thermal damage data with a theoretical thermal damage calculation utilizing a standard Arrhenius integral model.

C3 toxin and poly-DL-lactide-ε-caprolactone conduits in the critically damaged peripheral nervous system: a combined therapeutic approach.

PubMed

Leibig, Nico; Boyle, Veronika; Kraus, Daniel; Stark, Gerhard Bjoern; Penna, Vincenzo

2015-03-01

Peripheral nerve regeneration over longer distances through conduits is limited. In the presented study, critical size nerve gap bridging with a poly-DL-lactide-ε-caprolactone (PLC) conduit was combined with application of C3 toxin to facilitate axonal sprouting. The PLC filled with fibrin (n = 10) and fibrin gel loaded with 1-μg C3-C2I and 2-μg C2II (n = 10) were compared to autologous nerve grafts (n = 10) in a 15-mm sciatic nerve gap lesion model of the rat. Functional and electrophysiological analyses were performed before histological evaluation. Evaluation of motor function and nerve conduction velocity at 16 weeks revealed no differences between the groups. All histological parameters and muscle weight were significantly elevated in nerve graft group. No differences were observed in both PLC groups. The PLCs are permissive for nerve regeneration over a 15-mm defect in rats. Intraluminal application of C3 toxin did not lead to significant enhancement of nerve sprouting.

Non-recurrent inferior laryngeal nerve identification during robotic thyroidectomy.

PubMed

Wang, C-C; Wu, C-H

2014-02-01

A non-recurrent inferior laryngeal nerve is a rare anomaly in which the nerve enters the larynx directly off the cervical vagus nerve, without descending to the thoracic level. It is very susceptible to damage during surgery. This report describes the important pre-operative radiological evaluations and surgical landmarks in a case of a non-recurrent inferior laryngeal nerve, identified during the recently developed technique of robotic thyroidectomy. A 38-year-old woman presented with suspected papillary microcarcinoma, as indicated by aspiration cytology. Pre-operative computed tomography showed a right aberrant subclavian artery that indicated a possible right non-recurrent inferior laryngeal nerve. Using robotic thyroidectomy methods, it was possible to carefully dissect along the thyroid capsule. The laryngeal entrance point of the right non-recurrent inferior laryngeal nerve (a constant anatomical landmark) was successfully identified via the three-dimensional, high-magnification views provided by the robotic endoscope. With proper knowledge of radiological and surgical anatomy, and the benefits of high-magnification endoscopic views, a non-recurrent inferior laryngeal nerve can be safely preserved during robotic surgery.

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

PubMed

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.

Implications of Sensory Stimulation in Self-Destructive Behavior.

ERIC Educational Resources Information Center

Edelson, Stephen M.

1984-01-01

The author extends the self stimulatory theory of self destructive behavior in autistic, schizophrenic, and mentally retarded individuals to suggest that damage of the skin's nerve structure lowers the tactile sensory threshold for physical input and enables individuals to obtain sensory stimulation by repeatedly depressing the damaged area. (CL)

[Regeneration and repair of peripheral nerves: clinical implications in facial paralysis surgery].

PubMed

Hontanilla, B; Vidal, A

2000-01-01

Peripheral nerve lesions are one of the most frequent causes of chronic incapacity. Upper or lower limb palsies due to brachial or lumbar plexus injuries, facial paralysis and nerve lesions caused by systemic diseases are one of the major goals of plastic and reconstructive surgery. However, the poor results obtained in repaired peripheral nerves during the Second World War lead to a pessimist vision of peripheral nerve repair. Nevertheless, a well understanding of microsurgical principles in reconstruction and molecular biology of nerve regeneration have improved the clinical results. Thus, although the results obtained are quite far from perfect, these procedures give to patients a hope in the recuperation of their lesions and then on function. Technical aspects in nerve repair are well established; the next step is to manipulate the biology. In this article we will comment the biological processes which appear in peripheral nerve regeneration, we will establish the main concepts on peripheral nerve repair applied in facial paralysis cases and, finally, we will proportionate some ideas about how clinical practice could be affected by manipulation of the peripheral nerve biology.

Treatment of paraesthesia following root canal treatment by intentional tooth replantation: a review of the literature and a case report.

PubMed

Tsesis, Igor; Taschieri, Silvio; Rosen, Eyal; Corbella, Stefano; Del Fabbro, Massimo

2014-01-01

Some endodontic procedures may cause damage to the inferior alveolar nerve, leading to paraesthesia. When such complication is due to extrusion of obturation material beyond the apex, it can be managed by intentional replantation (IR). IR consists of the removal of a tooth and its re-insertion into the socket after performing a proper root end manipulation. It is a relatively conservative procedure aimed at preserving the tooth and, with correct case selection, can provide a predictable outcome. The aim of the present paper is to report a case of paraesthesia following endodontic treatment of second mandibular molar successfully treated by intentional replantation. In our opinion this treatment modality may be considered when the extrusion of root canal filling material causes irritation to the periapical tissues and endodontic retreatment is unfeasible.

Treatment of leprosy/Hansen's disease in the early 21st century.

PubMed

Worobec, Sophie M

2009-01-01

Leprosy, or Hansen's disease (HD), is caused by Mycobacterium leprae, a slowly dividing mycobacterium that has evolved to be an intracellular parasite, causing skin lesions and nerve damage. Less than 5% of people exposed to M. leprae develop clinical disease. Host cell-mediated resistance determines whether an individual will develop paucibacillary or multibacillary disease. Hansen's disease is a worldwide disease with about 150 new cases reported annually in the United States. Effective anti-mycobacterial treatments are available, and many patients experience severe reversal and erythema nodosum leprosum reactions that also require treatment. Leprosy has been the target of a World Health Organization multiple drug therapy campaign to eliminate it as a national public health problem in member countries, but endemic regions persist. In the United States, the National Hansen's Disease Program has primary responsibility for medical care, research, and information.

MRS of brain metabolite levels demonstrates the ability of scavenging of excess brain glutamate to protect against nerve agent induced seizures.

PubMed

Ruban, Angela; Biton, Inbal E; Markovich, Arik; Mirelman, David

2015-02-02

This study describes the use of in vivo magnetic resonance spectrocopy (MRS) to monitor brain glutamate and lactate levels in a paraoxon (PO) intoxication model. Our results show that the administration of recombinant glutamate-oxaloacetate transaminase (rGOT) in combination with oxaloacetate (OxAc) significantly reduces the brain-accumulated levels of glutamate. Previously we have shown that the treatment causes a rapid decrease of blood glutamate levels and creates a gradient between the brain and blood glutamate levels which leads to the efflux of excess brain glutamate into the blood stream thereby reducing its potential to cause neurological damage. The fact that this treatment significantly decreased the brain glutamate and lactate levels following PO intoxication suggests that it could become a new effective neuroprotective agent.

Preoperative percutaneous cranial nerve mapping in head and neck surgery.

PubMed

Park, Jung I

2003-01-01

To identify and map the course of the peripheral branches of the cranial nerve preoperatively and percutaneously. Prospective study. Preoperative percutaneous nerve mapping performed prior to the operation under deep sedation or general anesthesia without muscle paralysis. Private office surgery suite, freestanding surgery center, and regional medical centers. A total of 142 patients undergoing head and neck surgery and facial plastic surgery between August 1994 and July 1999. Monopolar probe was used for nerve stimulation. Electromyographic reading was done through intramuscular bipolar recording electrodes. The equipment used was a nerve monitor. The mandibular divisions were tested in 142 cases, the frontal division in 60 cases, the accessory nerve in 12 cases, and the hypoglossal nerve in 3 cases. Satisfactory mappings were obtained in 115 cases of the mandibular division, 49 cases of the frontal division, 8 cases of the accessory division, and 1 case of the hypoglossal nerve. Preoperative percutaneous nerve mapping is a new method of identifying the location of the peripheral branches of the cranial nerves. Identifying and mapping the course of peripheral branches of the cranial nerves safely assists the head and neck surgeon in the placement of incisions in a favorable location and in the dissection of the area involving the nerves. Mapping alerts the surgeon to an area containing a nerve and allows the surgeon to avoid just the specific area where a nerve is present, preventing large-scale abandonment of unmapped areas for fear of potential nerve damage.

Promoting peripheral nerve regeneration with biodegradable poly (DL-lactic acid) films

PubMed Central

Li, Ruijun; Chen, Lei; Fu, Jinling; Liu, Zhigang; Wang, Shuang; Pan, Yuehai

2015-01-01

Regeneration and repair of peripheral nerve injury has always been a major problem in the clinic. The conventional technique based on suturing the nerve ends to each other coupled with the implantation of nerve conduits outside is associated with postoperative adhesions and scar problems. Recently, a novel biodegradable poly (DL-lactic acid) (PDLLA) film has been introduced. This novel anti-adhesion film has a porous structure with better mechanical properties, better flexibility, and more controllable degradation as compared to traditional non-porous nerve conduits. However, little is known about the effects of such PDLLA films on regeneration and repair of peripheral nerve injury in vivo. In this study, we evaluated the effects of PDLLA films implantation after sciatic nerve transection and anastomosis on subsequent sciatic nerve regeneration in vivo, using a rat sciatic nerve injury model. Sciatic nerve transection surgery coupled with direct suturing only, suturing and wrapping with traditional nerve conduits, or suturing and wrapping with PDLLA films was performed on adult Wistar rats. The additional wrapping with PDLLA films inhibited the nerve adhesion after 12 weeks recovery from surgery. It also increased the compound muscle action potentials and tibialis and gastrocnemius muscle wet weight ratio following 8 weeks recovery from surgery. Regenerated nerve fibers were relatively straight and the aligned structure was complete in rats with implantations of PDLLA films. The results suggested that PDLLA films can improve the nutritional status in the muscles innervated by the damaged nerves and promote nerve regeneration in vivo. PMID:26339372

Cranial nerve monitoring during subpial dissection in temporomesial surgery.

PubMed

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 hiatus via the intact arachnoid.

DHTKD1 Deficiency Causes Charcot-Marie-Tooth Disease in Mice.

PubMed

Xu, Wang-Yang; Zhu, Houbao; Shen, Yan; Wan, Ying-Han; Tu, Xiao-Die; Wu, Wen-Ting; Tang, Lingyun; Zhang, Hong-Xin; Lu, Shun-Yuan; Jin, Xiao-Long; Fei, Jian; Wang, Zhu-Gang

2018-07-01

DHTKD1, a part of 2-ketoadipic acid dehydrogenase complex, is involved in lysine and tryptophan catabolism. Mutations in DHTKD1 block the metabolic pathway and cause 2-aminoadipic and 2-oxoadipic aciduria (AMOXAD), an autosomal recessive inborn metabolic disorder. In addition, a nonsense mutation in DHTKD1 that we identified previously causes Charcot-Marie-Tooth disease (CMT) type 2Q, one of the most common inherited neurological disorders affecting the peripheral nerves in the musculature. However, the comprehensive molecular mechanism underlying CMT2Q remains elusive. Here, we show that Dhtkd1 -/- mice mimic the major aspects of CMT2 phenotypes, characterized by progressive weakness and atrophy in the distal parts of limbs with motor and sensory dysfunctions, which are accompanied with decreased nerve conduction velocity. Moreover, DHTKD1 deficiency causes severe metabolic abnormalities and dramatically increased levels of 2-ketoadipic acid (2-KAA) and 2-aminoadipic acid (2-AAA) in urine. Further studies revealed that both 2-KAA and 2-AAA could stimulate insulin biosynthesis and secretion. Subsequently, elevated insulin regulates myelin protein zero ( Mpz ) transcription in Schwann cells via upregulating the expression of early growth response 2 (Egr2), leading to myelin structure damage and axonal degeneration. Finally, 2-AAA-fed mice do reproduce phenotypes similar to CMT2Q phenotypes. In conclusion, we have demonstrated that loss of DHTKD1 causes CMT2Q-like phenotypes through dysregulation of Mpz mRNA and protein zero (P 0 ) which are closely associated with elevated DHTKD1 substrate and insulin levels. These findings further indicate an important role of metabolic disorders in addition to mitochondrial insufficiency in the pathogenesis of peripheral neuropathies. Copyright © 2018 American Society for Microbiology.

[Evaluation of motor and sensory neuroconduction of the median nerve in patients with carpal tunnel syndrome treated with non-coherent light emitted by gallium arsenic diodes].

PubMed

Viera Alemán, C; Purón, E; Hamilton, M L; Santos Anzorandia, C; Navarro, A; Pineda Ortiz, I

The treatment selection in the carpal tunnel syndrome according to the damage of the median nerve is important and all of these have adverse effects. A good alternative without undesired reactions is irradiation of the carpal tunnel with not coherent light between 920 and 940 nm emitted by gallium arsenide diodes, resembling the physic and therapeutic laser effects. Twenty-six female patients with idiopathic middle carpal tunnel syndrome were irradiated 15 minutes daily during three weeks. The median nerve motor and sensitive neuroconduction was studied before and immediately after the treatment. The abnormal neuroconduction variables (latency, amplitude and velocity conduction) did not modify when treatment concluded, in spite of all the patients reported disappearance of pain and numbness in damaged hands. Not coherent light does not change the fibers functional state explored by conventional neuroconductions techniques. It remains to know if this light produces fine fibers improvement.

Pregabalin in the treatment of inferior alveolar nerve paraesthesia following overfilling of endodontic sealer

PubMed Central

Alonso-Ezpeleta, Oscar; Martín, Pablo J.; López-López, José; Castellanos-Cosano, Lizett; Martín-González, Jenifer; Segura-Egea, Juan J.

2014-01-01

A case of orofacial pain and inferior alveolar nerve (IAN) paraesthesia after extrusion of endodontic sealer within the mandibular canal treated with prednisone and pregabalin is described. A 36-year-old woman underwent root canal treatment of the mandibular second right premolar tooth. Post-operative panoramic radiograph revealed the presence of radiopaque canal sealer in the mandibular canal. Damage to IAN consecutive to extrusion of endodontic sealer was diagnosed. Non-surgical management was decided, including: 1 mg/kg/day prednisone 2 times/day, once-daily regimen, and 150 mg/day pregabalin, two doses per day, monitoring the progress with periodic follow-up visits. Six weeks after the incident the signs and symptoms were gone. The complete resolution of paraesthesia and the control of pain achieved suggest that a non-surgical approach, combining prednisone and the GABA analogue pregabalin, is a good option in the management of the IAN damage subsequent to endodontic sealer extrusion. Key words:Endodontics, inferior alveolar nerve, neuropathic pain, orofacial pain, paraesthesia, pregabalin. PMID:24790724

THE CAFETERIA DIET INCREASES FAT MASS AND CHRONICALLY ELEVATES LUMBAR SYMPATHETIC NERVE ACTIVITY IN RATS

PubMed Central

Muntzel, Martin S.; Al-Naimi, Omar Ali S.; Barclay, Alicia; Ajasin, David

2012-01-01

Obesity causes sympathetic activation that promotes atherosclerosis, end-organ damage, and hypertension. Because high-fat induced weight gain in rats elevates plasma leptin at 1–3 days following onset of calorie dense diets, we hypothesized that diet-induced overfeeding will increase sympathetic activity within one week following onset of the regimen. To test this, we continuously measured sympathetic activity and blood pressure before and during the onset of diet-induced obesity using a high calorie cafeteria-style diet. Female Wistar rats, in which radiotelemeters had been implanted for continuous monitoring of lumbar sympathetic activity, mean arterial pressure, and heart rate, were randomly assigned to groups that received regular chow (control) or a cafeteria diet for a period of 15 days. This short-term cafeteria-feeding regimen caused modest but non-significant increases in body weight (P = 0.07) and a doubling of brown and white adipose tissue (P < 0.01). The increases in fat mass were accompanied by elevations in plasma leptin (P < 0.001) but no change in glucose. Overall heart rates and blood pressure were higher in cafeteria rats compared with controls (P < 0.05). Cafeteria diet-induced weight gain caused increases in lumbar sympathetic nerve activity that became significant by the 12th day of the diet (p < 0.001). These data show, for the first time, that the high-fat cafeteria-style diet stimulates sustained increases in lumbar sympathetic neural drive in rats. PMID:23090774

Prognosis of phrenic nerve injury following thoracic interventions: four new cases and a review.

PubMed

Ostrowska, Monika; de Carvalho, Mamede

2012-04-01

Phrenic nerve lesion is a known complication of thoracic surgical intervention, but it is rarely described following thymectomy and lung surgery. To review the literature on thoracic intervention and phrenic nerve lesion and to describe four new cases, in which regular neurophysiological studies were performed. We reviewed the literature concerning phrenic nerve lesion after cardiac, lung and thymus surgical interventions. We described four cases of phrenic nerve lesion, three associated with thymectomy and one in lung surgery. The review shows that cryogenic or thermal injuries during cardiac surgeries are associated with good prognosis. The information on the outcome of phrenic nerve lesion in thymectomy or lung surgery is insufficient. Our cases and this review suggest that phrenic lesion in the last two interventions are associated with a poor recovery. Our data suggests that the prognosis of phrenic nerve lesion following thoracic intervention depends on the nature of the damage. Probably, in thymectomy and lung surgery, nerve stretch or laceration are involved, consequently the outcome is poorer in comparison with cardiac surgery, where cold lesion is more frequent. Neurophysiological tests give a direct, quantified and reliable assessment of nerve regeneration. Copyright © 2011 Elsevier B.V. All rights reserved.

[Herpes zoster of the trigeminal nerve: a case report and review of the literature].

PubMed

Carbone, V; Leonardi, A; Pavese, M; Raviola, E; Giordano, M

2004-01-01

Herpes zoster (shingles) is caused when the varicella zoster virus that has remained latent since an earlier varicella infection (chicken-pox) is reactivated. Herpes Zoster is a less common and endemic disease than varicella: factors causing reactivation are still not well known, but it occurs in older and/or immunocompromised individuals. Following reactivation, centrifugal migration of herpes zoster virus (HZV) occurs along sensory nerves to produce a characteristic painful cutaneous or mucocutaneous vesicular eruption that is generally limited to the single affected dermatome. Herpes zoster may affect any sensory ganglia and its cutaneous nerve: the most common sites affected are thoracic dermatomes (56%), followed by cranial nerves (13%) and lumbar (13%), cervical (11%) and sacral nerves (4%). Among cranial nerves, the trigeminal and facial nerves are the most affected due to reactivation of HZV latent in gasserian and geniculated ganglia. The 1st division of the trigeminal nerve is commonly affected, whereas the 2nd and the 3rd are rarely involved. During the prodromal stage, the only presenting symptom may be odontalgia, which may prove to be a diagnostic challenge for the dentist, since many diseases can cause orofacial pain, and the diagnosis must be established before final treatment. A literature review of herpes zoster of the trigeminal nerve is presented and the clinical presentation, differential diagnosis and treatment modalities are underlined. A case report is presented.

Iatrogenic nerve injury in a national no-fault compensation scheme: an observational cohort study.

PubMed

Moore, A E; Zhang, J; Stringer, M D

2012-04-01

Iatrogenic nerve injury causes distress and disability, and often leads to litigation. The scale and profile of these injuries has only be estimated from published case reports/series and analyses of medicolegal claims.   To determine the current spectrum of iatrogenic nerve injury in New Zealand by analysing treatment injury claims accepted by a national no-fault compensation scheme. The Accident Compensation Corporation (ACC) provides national no-fault personal accident insurance cover, which extends to patients who have sustained a treatment injury from a registered healthcare professional. Nerve injury claims identified from 5227 treatment injury claims accepted by the ACC in 2009 were analysed. From 327 claims, 292 (89.3%) documenting 313 iatrogenic nerve injuries contained sufficient information for analysis. Of these, 211 (67.4%) occurred in 11 surgical specialties, particularly orthopaedics and general surgery; the remainder involved phlebotomy services, anaesthesia and various medical specialties. The commonest causes of injury were malpositioning (n = 40), venepuncture (n = 26), intravenous cannulation (n = 21) and hip arthroplasty (n = 21). Most commonly injured were the median nerve and nerve roots (n = 32 each), brachial plexus (n = 26), and the ulnar nerve (n = 25). At least 34 (11.6%) patients were referred for surgical management of their nerve injury. Iatrogenic nerve injuries are not rare and occur in almost all branches of medicine, with malpositioning under general anaesthesia and venepuncture as leading causes. Some of these injuries are probably unavoidable, but greater awareness of which nerves are at risk and in what context should facilitate the development and/or wider implementation of preventive strategies. © 2012 Blackwell Publishing Ltd.

A low dose of subperiosteal anaesthesia injection versus a high dose of infiltration anaesthesia to minimise the risk of nerve damage at implant placement: A randomised controlled trial.

PubMed

Sánchez-Siles, Mariano; Camacho-Alonso, Fabio; Salazar-Sánchez, Noemi; Aguinaga-Ontoso, Enrique; Muñoz, Javier Guardia; Calvo-Guirado, Jose Luis

2016-01-01

To evaluate whether a low-dose subperiosteal anaesthesia is effective in minimising risks of inferior alveolar nerve damage at implant placement when compared to high-dose infiltration anaesthesia. One hundred and twenty patients requiring the placement of a single implant in order to replace a missing first mandibular were randomly allocated to two groups: group A (awake hemilip) subperiosteal crestal injection equal to 0.9 ml of articaine with 0.5% epinephrine and group B (numb hemilip) infiltration equal to 7.2 ml of articaine with 0.5% epinephrine in the vestibular fundus. Intraoperative sensory control using sensory tests was carried out in all patients. Outcome measures were neurological complications, intraoperative and postoperative visual analogue scale (VAS) scores for pain and swelling, and a questionnaire evaluating patient satisfaction. Patients were followed for 1 week postoperatively. There were no cases of nerve injury. Seven days after surgery the postoperative VAS score for pain and swelling was lower in group A in a statistically significant manner (difference = -3.41%; 95% CI: -5.57, -1.26; P = 0.002 and difference = -3.33%; 95% CI: -5.41, -1.25; P = 0.002, respectively). No nerve damage occurred using either anaesthesia types, therefore the choice of type of anaesthesia is a subjective clinical decision, however it may be preferable to use a low dose (0.9 ml) of subperiosteal anaesthesia, since it is unnecessary to deliver 7.2 ml of articaine to anaesthetise a single mandibular molar implant site.

Reliability and sensitivity of the TonoLab rebound tonometer in awake Brown Norway rats.

PubMed

Morrison, John C; Jia, Lijun; Cepurna, William; Guo, Ying; Johnson, Elaine

2009-06-01

To compare the sensitivity of the TonoLab rebound tonometer with the Tono-Pen in awake Brown Norway rats and to compare their ability to predict optic nerve damage induced by experimental IOP elevation. TonoLab and Tono-Pen tonometers were calibrated in cannulated rat eyes connected to a pressure transducer. The TonoLab was used in awake animals housed in standard lighting to measure IOP during light and dark phases. Both instruments were used to monitor chronically elevated IOP produced by episcleral vein injection of hypertonic saline. Measured IOPs were correlated with quantified optic nerve damage in injected eyes. Although they were lower than transducer and Tono-Pen measurements at all levels, TonoLab readings showed an excellent linear fit with transducer readings from 20 to 80 mm Hg (R(2) = 0.99) in cannulated eyes. In awake animals housed in standard lighting, the TonoLab documented significantly higher pressures during the dark phase (27.9 +/- 1.7 mm Hg) than during the light phase (16.7 +/- 2.3 mm Hg). With elevated IOP, correlation between TonoLab and Tono-Pen readings (R(2) = 0.86, P < 0.0001) was similar to that in cannulated eyes. Although both instruments provided measurements that correlated well with optic nerve injury grade, only the Tono-Pen documented significant IOP elevation in eyes with the least amount of injury (P < 0.05). The TonoLab is sensitive enough to be used in awake Brown Norway rats, though instrument fluctuation may limit its ability to identify significant pressure elevations in eyes with minimal optic nerve damage.

Selenium Ameliorate Peripheral Nerve Ischemic-Reperfusion Injury via Decreased TNF-α.

PubMed

Zendedel, Abolfazl; Gharibi, Zahra; Anbari, Khatereh; Abbaszadeh, Abolfazl; Khayat, Zahra Khanipour; Khorramabadi, Reza Mohammadrezaei; Soleymaninejad, Maryam; Gholami, Mohammadreza

2017-04-01

Selenium is considered as a trace element that plays antioxidant role in the body. So, the aim of this study was to evaluate the effect of selenium on ameliorating of sciatic nerve ischemia-reperfusion injury. Eighty (80) adult male Wistar rats weighing 250-300 g were used. They were divided into 10 groups (n = 8). Then, femoral vessels were obstructed by using 4/0 silk and splitknot techniques. After 3-h ischemia for all the groups, reperfusion was applied for different periods: 3, 7, 14, and 28 days. In half of each experimental group, 0.2 mg/kg selenium was injected intraperitoneally, coinciding with ischemia. After reperfusion, according to the grouping, rats were killed by using high dose of anesthetic drug and then sciatic nerve was removed and fixed. Then, tissue samples were processed and subsequently stained with hematoxylin-eosin, apoptosis, and immunohistochemistry stains. On the third day of reperfusion, the amount of TNF-α as an inflammatory marker of ischemia-reperfusion acute phase increased. On the seventh day of reperfusion, the amount of NF-кB as an apoptotic index and infiltration of mast cells increased in the tissue as a result of development of inflammation. But, on the 14th day of reperfusion, the amount of NF-кB as an apoptotic index decreased to the lowest amount. On the 28th day of reperfusion, the amount of TNF-α as an inflammatory marker decreased to its lowest level. Prescription of selenium concurrent with development of ischemia can reduce the damage caused by sciatic nerve ischemia-reperfusion.

Experiment K-6-09. Morphological and biochemical investigation of microgravity-induced nerve and muscle breakdown. Part 1: Investigation of nerve and muscle breakdown during spaceflight; Part 2: Biochemical analysis of EDL and PLT muscles

NASA Technical Reports Server (NTRS)

Riley, D. A.; Ellis, S.; Bain, J.; Sedlak, F.; Slocum, G.; Oganov, V.

1990-01-01

The present findings on rat hindlimb muscles suggest that skeletal muscle weakness induced by prolonged spaceflight can result from a combination of muscle fiber atrophy, muscle fiber segmental necrosis, degeneration of motor nerve terminals and destruction of microcirculatory vessels. Damage was confined to the red adductor longus (AL) and soleus muscles. The midbelly region of the AL muscle had more segmental necrosis and edema than the ends. Macrophages and neutrophils were the major mononucleated cells infiltrating and phagocytosing the cellular debris. Toluidine blue-positive mast cells were significantly decreased in Flight AL muscles compared to controls; this indicated that degranulation of mast cells contributed to tissue edema. Increased ubiquitination of disrupted myofibrils may have promoted myofilament degradation. Overall, mitochondria content and SDH activity were normal, except for a decrease in the subsarcolemmal region. The myofibrillar ATPase activity shifted toward the fast type in the Flight AL muscles. Some of the pathological changes may have occurred or been exacerbated during the 2 day postflight period of readaptation to terrestrial gravity. While simple atrophy should be reversible by exercise, restoration of pathological changes depends upon complex processes of regeneration by stem cells. Initial signs of muscle and nerve fiber regeneration were detected. Even though regeneration proceeds on Earth, the space environment may inhibit repair and cause progressive irreversible deterioration during long term missions. Muscles obtained from Flight rats sacrificed immediately (within a few hours) after landing are needed to distinguish inflight changes from postflight readaptation.

An update on pathobiologic roles of anti-glycan antibodies in Guillain-Barré syndrome

PubMed Central

Zhang, Gang

2010-01-01

Anti-glycan antibodies directed against gangliosides are now considered the major immune effectors that induce damage to intact nerve fibers in some variants of the monophasic neuropathic disorders that comprise Guillain-Barré syndrome. Recent experimental studies elucidating the complexity of anti-glycan antibody-mediated pathobiologic effects on intact and injured nerves undergoing repair are discussed. PMID:20948812

Occipital artery vasculitis not identified as a mechanism of occipital neuralgia-related chronic migraine headaches.

PubMed

Ducic, Ivica; Felder, John M; Janis, Jeffrey E

2011-10-01

Recent evidence has shown that some cases of occipital neuralgia are attributable to musculofascial compression of the greater occipital nerve and improve with neurolysis. A mechanical interaction at the intersection of the nerve and the occipital artery may also be capable of producing neuralgia, although that mechanism remains one theoretical possibility among several. The authors evaluated the possibility of unrecognized vasculitis of the occipital artery as a potential mechanism of occipital neuralgia arising from the occipital artery/greater occipital nerve junction. Twenty-five patients with preoperatively documented bilateral occipital neuralgia-related chronic headaches underwent peripheral nerve surgery with decompression of the greater occipital nerve bilaterally, including the area of its intersection with the occipital artery. In 15 patients, a 2-cm segment of the occipital artery was excised and submitted for pathologic evaluation. All patients were evaluated intraoperatively for evidence of arterially mediated greater occipital nerve compression, and the configuration of the nerve-vessel intersection was noted. None of the 15 specimens submitted for pathologic evaluation showed vasculitis. Intraoperatively, all 50 sites examined showed an intimate physical association between the occipital artery and greater occipital nerve. Surgical specimens from this first in vivo study provided no histologic evidence of vasculitis as a cause of greater occipital nerve irritation at the occipital artery/greater occipital nerve junction in patients with chronic headaches caused by occipital neuralgia. Based on these findings, mechanical (and not primary inflammatory) irritation of the nerve by the occipital artery remains an important theoretical cause for otherwise idiopathic cases. The authors have adopted an operative technique that includes physical separation of the nerve-artery intersection (in addition to musculofascial neurolysis) for a more thorough surgical treatment of occipital neuralgia. Therapeutic, IV.

Effects of hyperbaric oxygen and nerve growth factor on the long-term neural behavior of neonatal rats with hypoxic ischemic brain damage.

PubMed

Wei, Lixia; Ren, Qing; Zhang, Yongjun; Wang, Jiwen

2017-04-01

To evaluate the effects of HBO (Hyperbaric oxygen) and NGF (Nerve growth factor) on the long-term neural behavior of neonatal rats with HIBD (Neonatal hypoxic ischemic brain damage). The HIBD model was produced by ligating the right common carotid artery of 7 days old SD (Sprague-Dawley) rats followed by 8% O2 + 92% N2 for 2h. Totally 40 rats were randomly divided into 5 groups including sham-operated group, HIBD control group, HBO treated group, NGF treated group and NGF + HBO treated group. The learning and memory ability of these rats was evaluated by Morris water maze at 30 days after birth, and sensory motor function was assessed by experiments of foot error and limb placement at 42 days after birth. The escape latency of HBO treated group, NGF treated group and NGF + HBO treated group was shorter than that of HIBD control group (p<0.01) and longer than that of sham-operated group. The piercing indexes of 3 treated groups were higher than that of HIBD control group (p<0.01). Hyperbaric oxygen and nerve growth factor treatments may improve learning and memory ability and sensory motor function in neonatal rats after hypoxic ischemic brain damage.

Invaginated axial saphenectomy by a semirigid stripper: perforate-invaginate stripping.

PubMed

Goren, G; Yellin, A E

1994-12-01

This study was designed to evaluate a recently introduced form of stripping of primary varicose veins by the technique of perforate-invaginate (PIN) stripping. One hundred twelve consecutive limbs presenting with 91 long and 21 short saphenous varicosities displaying saphenofemoral or saphenopopliteal junctional escapes with varying length of greater or lesser saphenous (axial) reflux underwent operation in 1 year. All surgeries were performed in an office setting with the patient receiving locoregional anesthetic with use of the invaginated PIN stripping in conjunction with tributary hook-stab avulsion. In the 112 procedures performed, there were no tract hematomas or dysesthesias caused by nerve damage. Postoperative morbidity was nonexistent, permitting all patients to resume normal daily occupational and sporting activities immediately. PIN stripping is an excellent method of invagination stripping. There is a minimal likelihood of vein tearing. Compared with conventional ankle-to-groin (or popliteal fossa) stripping, PIN stripping is minimally invasive, does not cause damage to structures around the vein, does not require convalescence, eliminates the need for a lengthy distal second incision, can be performed in an office setting with the patient receiving locoregional anesthetic, and is most cost-efficient.

Advanced Optical Technologies for Defense Trauma and Critical Care

DTIC Science & Technology

2017-03-12

biofilms, and the development of innovative technologies for the study of the response of nervous system cells to injury. 15. SUBJECT TERMS Hemorrhagic...approaches to accelerate nerve healing following traumatic brain injury (TBI) and traumatic injury to the peripheral nervous system . Fig. 3...Two key aspects of repair of traumatic nervous system damage are: (1) the ability of damaged neurons to heal (repair the damage), and (2) the

Nerve Entrapment Syndromes at the Wrist and Elbow by Sonography.

PubMed

Klauser, Andrea S; Buzzegoli, Tommaso; Taljanovic, Mihra S; Strobl, Sylvia; Rauch, Stefan; Teh, James; Wanschitz, Julia; Löscher, Wolfgang; Martinoli, Carlo

2018-07-01

Nerve entrapment syndromes of the upper extremity are associated with structural abnormalities or by an intrinsic abnormality of the nerve. Nerve entrapment syndromes generally have a typical clinical presentation, and findings on physical examination and in conjunction with electrodiagnostic studies imaging is used to evaluate the cause, severity, and etiology of the entrapment. With the development of high-frequency linear array transducers (12-24 MHz), ultrasound (US) is incomparable in terms of spatial resolution to depict morphological aspects and changes in nerves. US can identify the abnormalities causing entrapment, such as fibrous bands, ganglia, anomalous muscles, and osseous deformities, with the advantage of dynamic assessment under active and passive examination. US is a unique diagnostic modality that allows superb visualization of both large and small peripheral terminal nerve branches of the upper extremity and enables the correct diagnosis of various nerve entrapment syndromes. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Correlative CT and anatomic study of the sciatic nerve

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pech, P.; Haughton, V.

1985-05-01

Sciatica can be caused by numerous processes affecting the sciatic nerve or its components within the pelvis including tumors, infectious diseases, aneurysms, fractures, and endometriosis. The CT diagnosis of these causes of sciatica has not been emphasized. This study identified the course and appearance of the normal sciatic nerve in the pelvis by correlating CT and anatomic slices in cadavers. For purposes of discussion, the sciatic nerve complex is conveniently divided into three parts: presacral, muscular, and ischial. Each part is illustrated here by two cryosections with corresponding CT images.

Microsurgical anatomy of the abducens nerve.

PubMed

Joo, Wonil; Yoshioka, Fumitaka; Funaki, Takeshi; Rhoton, Albert L

2012-11-01

The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Copyright © 2012 Wiley Periodicals, Inc.

Facial nerve paralysis in children

PubMed Central

Ciorba, Andrea; Corazzi, Virginia; Conz, Veronica; Bianchini, Chiara; Aimoni, Claudia

2015-01-01

Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital (due to delivery traumas and genetic or malformative diseases) or acquired (due to infective, inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology. PMID:26677445

Controlled circumferential renal sympathetic denervation with preservation of the renal arterial wall using intraluminal ultrasound: a next-generation approach for treating sympathetic overactivity.

PubMed

Sakakura, Kenichi; Roth, Austin; Ladich, Elena; Shen, Kai; Coleman, Leslie; Joner, Michael; Virmani, Renu

2015-02-01

The Paradise Ultrasound Renal Denervation System is a next-generation catheter-based device which was used to investigate whether the target ablation area can be controlled by changing ultrasound energy and duration to optimise nerve injury while preventing damage to the arterial wall. Five ultrasound doses were tested in a thermal gel model. Catheter-based ultrasound denervation was performed in 15 swine (29 renal arteries) to evaluate five different doses in vivo, and animals were euthanised at seven days for histopathologic assessment. In the gel model, the peak temperature was highest in the low power-long duration (LP-LD) dose, followed by the mid-low power-mid duration (MLP-MD) dose and the mid-high power-short duration (MHP-SD) dose, and lowest in the mid power-short duration (MP-SD) dose and the high power-ultra short duration (HP-USD) dose. In the animal study, total ablation area was significantly greater in the LP-LD group, followed by the MLP-MD group, and it was least in the HP-USD, MP-SD and MHP-SD groups (p=0.02). Maximum distance was significantly greater in the LP-LD group, followed by the MLP-MD group, the MHP-SD group, and the HP-USD group, and shortest in the MP-SD group (p=0.007). The short spare distance was not different among the five groups (p=0.38). Renal artery damage was minimal, while preserving significant nerve damage in all groups. The Paradise Ultrasound Renal Denervation System is a controllable system where total ablation area and depth of ablation can be optimised by changing ultrasound power and duration while sparing renal arterial tissue damage but allowing sufficient peri-arterial nerve damage.

The Uncommon Localization of Herpes Zoster

PubMed Central

Cukic, Vesna

2016-01-01

Introduction: Herpes zoster is an acute, cutaneous viral infection caused by the reactivation of varicella-zoster virus (VZV) that is the cause of varicella. It is an acute neurological disease which can often lead to serious postherpetic neuralgia (PHN). Different nerves can be included with the skin rash in the area of its enervation especially cranial nerves (CV) and intercostal nerves. Case report: In this report we present a patient with herpes zoster which involved ulnar nerve with skin rash in the region of ulnar innervations in women with no disease previously diagnosed. The failure of her immune system may be explained by great emotional stress and overwork she had been exposed to with neglecting proper nutrition in that period. Conclusion: Herpes zoster may involve any nerve with characteristic skin rash in the area of its innervations, and failure in immune system which leads reactivation of VZV may be caused by other factors besides the underlying illness. PMID:26980938

Pregabalin

MedlinePlus

Pregabalin capsules, oral solution (liquid), and extended-release (long-acting) tablets are used to relieve neuropathic pain (pain from damaged nerves) that can occur in your arms, hands, fingers, ...

Methods for determination of optic nerve blood flow.

PubMed Central

Glazer, L. C.

1988-01-01

A variety of studies have been conducted over the past two decades to determine if decreased optic nerve blood flow has a role in the etiology of glaucomatous nerve damage. Five basic methods have been employed in examining blood flow. Invasive studies, utilizing electrodes placed in the optic nerve head, represent one of the first attempts to measure blood flow. More recently, the methodologies have included axoplasmic flow analysis, microspheres, radioactive tracers such as iodoantipyrine, and laser doppler measurements. The results of these studies are inconclusive and frequently contradictory. When the studies are grouped by methodology, only the iodoantipyrine data are consistent. While each of the experimental techniques has limitations, iodoantipyrine appears to have better resolution than either invasive studies or microspheres. PMID:3284212

Nerve regeneration with aid of nanotechnology and cellular engineering.

PubMed

Sedaghati, Tina; Yang, Shi Yu; Mosahebi, Afshin; Alavijeh, Mohammad S; Seifalian, Alexander M

2011-01-01

Repairing nerve defects with large gaps remains one of the most operative challenges for surgeons. Incomplete recovery from peripheral nerve injuries can produce a diversity of negative outcomes, including numbness, impairment of sensory or motor function, possibility of developing chronic pain, and devastating permanent disability. In the last few years, numerous microsurgical techniques, such as coaptation, nerve autograft, and different biological or polymeric nerve conduits, have been developed to reconstruct a long segment of damaged peripheral nerve. A few of these techniques are promising and have become popular among surgeons. Advancements in the field of tissue engineering have led to development of synthetic nerve conduits as an alternative for the nerve autograft technique, which is the current practice to bridge nerve defects with gaps larger than 30 mm. However, to date, despite significant progress in this field, no material has been found to be an ideal alternative to the nerve autograft. This article briefly reviews major up-to-date published studies using different materials as an alternative to the nerve autograft to bridge peripheral nerve gaps in an attempt to assess their ability to support and enhance nerve regeneration and their prospective drawbacks, and also highlights the promising hope for nerve regeneration with the next generation of nerve conduits, which has been significantly enhanced with the tissue engineering approach, especially with the aid of nanotechnology in development of the three-dimensional scaffold. The goal is to determine potential alternatives for nerve regeneration and repair that are simply and directly applicable in clinical conditions. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Rodent model for assessing the long term safety and performance of peripheral nerve recording electrodes

NASA Astrophysics Data System (ADS)

Vasudevan, Srikanth; Patel, Kunal; Welle, Cristin

2017-02-01

Objective. In the US alone, there are approximately 185 000 cases of limb amputation annually, which can reduce the quality of life for those individuals. Current prosthesis technology could be improved by access to signals from the nervous system for intuitive prosthesis control. After amputation, residual peripheral nerves continue to convey motor signals and electrical stimulation of these nerves can elicit sensory percepts. However, current technology for extracting information directly from peripheral nerves has limited chronic reliability, and novel approaches must be vetted to ensure safe long-term use. The present study aims to optimize methods to establish a test platform using rodent model to assess the long term safety and performance of electrode interfaces implanted in the peripheral nerves. Approach. Floating Microelectrode Arrays (FMA, Microprobes for Life Sciences) were implanted into the rodent sciatic nerve. Weekly in vivo recordings and impedance measurements were performed in animals to assess performance and physical integrity of electrodes. Motor (walking track analysis) and sensory (Von Frey) function tests were used to assess change in nerve function due to the implant. Following the terminal recording session, the nerve was explanted and the health of axons, myelin and surrounding tissues were assessed using immunohistochemistry (IHC). The explanted electrodes were visualized under high magnification using scanning electrode microscopy (SEM) to observe any physical damage. Main results. Recordings of axonal action potentials demonstrated notable session-to-session variability. Impedance of the electrodes increased upon implantation and displayed relative stability until electrode failure. Initial deficits in motor function recovered by 2 weeks, while sensory deficits persisted through 6 weeks of assessment. The primary cause of failure was identified as lead wire breakage in all of animals. IHC indicated myelinated and unmyelinated axons near the implanted electrode shanks, along with dense cellular accumulations near the implant site. Scanning electron microscopy (SEM) showed alterations of the electrode insulation and deformation of electrode shanks. Significance. We describe a comprehensive testing platform with applicability to electrodes that record from the peripheral nerves. This study assesses the long term safety and performance of electrodes in the peripheral nerves using a rodent model. Under this animal test platform, FMA electrodes record single unit action potentials but have limited chronic reliability due to structural weaknesses. Future work will apply these methods to other commercially-available and novel peripheral electrode technologies. This research was carried out in the Division of Biomedical Physics, Office of Science and Engineering Laboratory, Center for Devices and Radiological Health, US Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA.

Peripheral Nerve Regeneration Strategies: Electrically Stimulating Polymer Based Nerve Growth Conduits

PubMed Central

Anderson, Matthew; Shelke, Namdev B.; Manoukian, Ohan S.; Yu, Xiaojun; McCullough, Louise D.; Kumbar, Sangamesh G.

2017-01-01

Treatment of large peripheral nerve damages ranges from the use of an autologous nerve graft to a synthetic nerve growth conduit. Biological grafts, in spite of many merits, show several limitations in terms of availability and donor site morbidity, and outcomes are suboptimal due to fascicle mismatch, scarring, and fibrosis. Tissue engineered nerve graft substitutes utilize polymeric conduits in conjunction with cues both chemical and physical, cells alone and or in combination. The chemical and physical cues delivered through polymeric conduits play an important role and drive tissue regeneration. Electrical stimulation (ES) has been applied toward the repair and regeneration of various tissues such as muscle, tendon, nerve, and articular tissue both in laboratory and clinical settings. The underlying mechanisms that regulate cellular activities such as cell adhesion, proliferation, cell migration, protein production, and tissue regeneration following ES is not fully understood. Polymeric constructs that can carry the electrical stimulation along the length of the scaffold have been developed and characterized for possible nerve regeneration applications. We discuss the use of electrically conductive polymers and associated cell interaction, biocompatibility, tissue regeneration, and recent basic research for nerve regeneration. In conclusion, a multifunctional combinatorial device comprised of biomaterial, structural, functional, cellular, and molecular aspects may be the best way forward for effective peripheral nerve regeneration. PMID:27278739

Neurophysiological Identification of Cranial Nerves During Endoscopic Endonasal Surgery of Skull Base Tumors: Pilot Study Technical Report.

PubMed

Shkarubo, Alexey Nikolaevich; Chernov, Ilia Valerievich; Ogurtsova, Anna Anatolievna; Moshchev, Dmitry Aleksandrovich; Lubnin, Andrew Jurievich; Andreev, Dmitry Nicolaevich; Koval, Konstantin Vladimirovich

2017-02-01

Intraoperative identification of cranial nerves is crucial for safe surgery of skull base tumors. Currently, only a small number of published papers describe the technique of trigger electromyography (t-EMG) in endoscopic endonasal removal of such tumors. To assess the effectiveness of t-EMG in preventing intraoperative cranial nerve damage in endoscopic endonasal surgery of skull base tumors. Nine patients were operated on using the endoscopic endonasal approach within a 1-year period. The tumors included large skull base chordomas and trigeminal neurinomas localized in the cavernous sinus. During the surgical process, cranial nerve identification was carried out using monopolar and bipolar t-EMG methods. Assessment of cranial nerve functional activity was conducted both before and after tumor removal. We mapped 17 nerves in 9 patients. Third, fifth, and sixth cranial nerves were identified intraoperatively. There were no cases of postoperative functional impairment of the mapped cranial nerves. In one case we were unable to get an intraoperative response from the fourth cranial nerve and observed its postoperative transient plegia (the function was normal before surgery). t-EMG allows surgeons to control the safety of cranial nerves both during and after skull base tumor removal. Copyright © 2016 Elsevier Inc. All rights reserved.

Lead-induced changes of cytoskeletal protein is involved in the pathological basis in mice brain.

PubMed

Ge, Yaming; Chen, Lingli; Sun, Xianghe; Yin, Zhihong; Song, Xiaochao; Li, Chong; Liu, Junwei; An, Zhixing; Yang, Xuefeng; Ning, Hongmei

2018-04-01

Lead poisoning is a geochemical disease. On the other hand, lead is highly carcinogenic and exhibits liver and kidney toxicity. This element can also cross the blood-brain barrier, reduce learning and memory ability and damage the structure of the cerebral cortex and hippocampus. To further investigate the mechanism of lead neurotoxicity, 4-week-old Kunming mice were used to explore the effects of different concentrations of Pb 2+ (0, 2.4, 4.8 and 9.6 mM) for 9 days. In this study, pathological and ultrastructural changes in brain cells of the treated group were related to damages to mitochondria, chromatin and the nucleus. Lead content in blood was tested by atomic absorption spectroscopy, which showed high lead concentrations in the blood with increasing doses of lead. Distribution of lead in nerve cells was analysed by transmission electron microscopy with energy dispersive spectroscopy. Data showed the presence of lead in nucleopores, chromatin and nuclear membrane of nerve cells in the treatment groups, whereas lead content increased with increasing doses of lead acetate. Finally, microtubule-associated protein 2 (MAP2) mRNA and protein expression levels were detected by real-time PCR and Western blotting, which showed a reduction in MAP2 expression with increasing lead doses in the mouse brain. These findings suggest that acute lead poisoning can cause significant dose-dependent toxic effects on mouse brain function and can contribute to better understanding of lead-induced toxicity.