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Affected Nerve (affected + nerve)
Selected AbstractsSensory nerve conduction deficit in experimental monoclonal gammopathy of undetermined significance (MGUS) neuropathyMUSCLE AND NERVE, Issue 6 2001Michael W. Lawlor BS Abstract An emerging body of evidence from in vitro studies and in vivo animal models supports a pathogenic role of antibodies in the development of peripheral neuropathy associated with monoclonal gammopathy of undetermined significance (MGUS). Although the assessment of motor and sensory nerve fiber function is of clinical importance, it is seldom applied experimentally. We describe the application of an electrophysiologic method for the evaluation of motor and sensory nerve fiber function using an experimental model of MGUS neuropathy. Supramaximal stimulation of the tibial nerve elicited an early motor response (M-wave, 1.7 ± 0.1 ms, n = 10) and a late sensory (H-reflex, 7.8 ± 0.1 ms, n = 10) response that was recorded from the hind foot of anesthetized rats. Intraneural injection of serum antibodies from a MGUS patient with sensorimotor polyneuropathy, but not from an age-matched control subject, produced a marked attenuation of the H-reflex (P < 0.01, n = 10) without affecting the M-wave. Light and electron microscopy of affected nerve showed myelinoaxonal degeneration with sparing of the smaller unmyelinated nerve fibers. The combined electrophysiologic and morphologic findings presented in this study are consistent with a selective sensory conduction deficit in MGUS neuropathy. Selective injury of afferent nerve fibers by this patient's serum antibodies may result from reactivity to neural antigens uniquely expressed by sensory neurons. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 809,816, 2001 [source] Perineurioma of the mandibular dental nerve: a case report and review of the literatureORAL SURGERY, Issue 2 2009E.F. Vencio Abstract Perineurioma is an uncommon benign tumour of the nerve sheath composed exclusively of well-differentiated perineurial cells. It usually affects the limbs or trunk; intraoral lesions are uncommon. A rare case of perineurioma is described involving the mandibular dental nerve in a 59-year-old female, microscopically characterised by a combined pattern of intraneural and soft tissue perineurioma. The patient was referred for treatment of a lesion in the mandible. Panoramic radiography revealed a well-delimited osteolytic lesion with radiopaque halo in an edentulous region of the left mandible. Occlusal view showed no expansion of cortical bone. A surgical procedure for incisional biopsy disclosed a connection between the tumour and the alveolar inferior nerve. Grossly, an enlargement of the affected nerve was described. Microscopic examination showed tumour cells arranged in pseudo-onion bulb structures, with scattered collagen bundles, and areas with a whorled (storiform) arrangement. Many concentric whorls of spindle cells exhibiting thin, elongated eosinophic processes were seen. Immunohistochemical study exhibited strong positivity for epithelial membrane antigen. We report a rare case of perineurioma affecting the mandibular dental nerve showing both intraneural and soft tissue microscopic patterns and discuss morphological aspects for differential diagnosis. [source] Disruption of axoplasmic transport induces mechanical sensitivity in intact rat C-fibre nociceptor axonsTHE JOURNAL OF PHYSIOLOGY, Issue 2 2008Andrew Dilley Peripheral nerve inflammation can cause axons conducting through the inflamed site to become mechanically sensitive. Axonal mechanical sensitivity (AMS) of intact axons may explain symptoms in a diverse number of conditions characterized by radiating pain evoked by movements of the affected nerve. Because nerve inflammation also disrupts axoplasmic transport, we hypothesized that the disruption of axoplasmic transport by nerve inflammation could cause the cellular components responsible for mechanical transduction to accumulate and become inserted at the inflamed site, causing AMS. This was tested by examining AMS in C-fibre nociceptors following the application of axoplasmic transport blockers (colchicine and vinblastine) to the sciatic nerve. Both 10 mm colchicine and 0.1 mm vinblastine caused AMS to develop in 30.6% and 33.3% of intact axons, respectively (P < 0.05 compared to sham treatment). Since high doses of colchicine (> 50 mm) can damage axons, and inflammation is involved in the removal of axonal debris, experiments were performed to assess conduction across the treatment site as well as signs of inflammation. Results indicated minimal axonal loss (95% of A- and C-fibres conducting), consistent with the normal microscopic appearance of the colchicine treatment site and absence of ED1-positive (recruited) macrophages. In a separate series of experiments, the block of axoplasmic transport proximal to a localized neuritis significantly reduced inflammation-induced AMS (15.6% compared to 55.6%; P < 0.05), further supporting that the components necessary for AMS are moved by anterograde transport. In summary, nerve inflammation that causes the disruption of axoplasmic transport in patients with painful conditions may result in the accumulation and insertion of mechanosensitive elements at the inflamed site. [source] Combined endovascular and surgical treatment of head and neck paragangliomas,A team approach,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2002Mark S. Persky MD Abstract Background Paragangliomas are highly vascular tumors of neural crest origin that involve the walls of blood vessels or specific nerves within the head and neck. They may be multicentric, and they are rarely malignant. Surgery is the preferred treatment, and these tumors frequently extend to the skull base. There has been controversy concerning the role of preoperative angiography and embolization of these tumors and the benefits that these procedures offer in the evaluation and management of paragangliomas. Methods Forty-seven patients with 53 paragangliomas were treated from the period of 1990,2000. Initial evaluation usually included CT and/or MRI. All patients underwent bilateral carotid angiography, embolization of the tumor nidus, and cerebral angiography to define the patency of the circle of Willis. Carotid occlusion studies were performed with the patient under neuroleptic anesthesia when indicated. The tumors were excised within 48 hours of embolization. Results Carotid body tumors represented the most common paraganglioma, accounting for 28 tumors (53%). All patients underwent angiography and embolization with six patients (13%), demonstrating complications (three of these patients had embolized tumor involving the affected nerves). Cerebral angiography was performed in 28 patients, and 5 of these patients underwent and tolerated carotid occlusion studies. The range of mean blood loss according to tumor type was 450 to 517 mL. Postoperative cranial nerve dysfunction depended on the tumor type resected. Carotid body tumor surgery frequently required sympathetic chain resection (21%), with jugular and vagal paraganglioma removal frequently resulting in lower cranial nerve resection. These patients required various modes of postoperative rehabilitation, especially vocal cord medialization and swallowing therapy. Conclusions The combined endovascular and surgical treatment of paragangliomas is acceptably safe and effective for treating these highly vascular neoplasms. Adequate resection may often require sacrifice of one or more cranial nerves, and appropriate rehabilitation is important in the treatment regimen. © 2002 Wiley Periodicals, Inc. [source] Towards development of a nonhuman primate model of carpal tunnel syndrome: Performance of a voluntary, repetitive pinching task induces median mononeuropathy in Macaca fascicularisJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2007Carolyn M. Sommerich Abstract This study investigated changes in median sensory nerve conduction velocity (SNCV) over several weeks of exposure to a voluntary, moderately forceful, repetitive pinching task performed for food rewards by a small sample of young adult female monkeys (Macaca fascicularis). SNCV, derived from peak latency, decreased significantly in the working hands of three of the four subjects. The overall decline in NCV was 25%,31% from baseline. There was no decrease in SNCV in the contralateral, nonworking hands. Several weeks after being removed from the task, SNCV returned to within 87%,100% of baseline. MRI showed enlargement of the affected nerves near the proximal end of the carpal tunnel, at the time of maximal SNCV slowing. This new animal model demonstrates a temporally unambiguous relationship between exposure to a moderately forceful, repetitive manual task and development of median mononeuropathy at the wrist, and recovery of SNCV following termination of task exposure. This study contributes to the pattern of evidence of a causal relationship between manual work, median mononeuropathy, and carpal tunnel syndrome in humans. In the future, this new animal model could be used to characterize dose,response relationships between risk factors and carpal tunnel syndrome. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25: 713,724, 2007 [source] Herpes zoster in older adults. (Duke University Medical Center, Durham, NC) Clinical Infectious Diseases.PAIN PRACTICE, Issue 4 20011486., 2001;32:148 Herpes zoster (HZ) strikes millions of older adults annually worldwide and disables a substantial number of them via postherpetic neuralgia (PHN). Key aged-related clinical, epidemiological, and treatment features of zoster and PHN are reviewed in this article. HZ is caused by renewed replication and spread of the varicella-zoster virus (VZV) in sensory ganglia and afferent peripheral nerves in the setting of age-related, disease-related, and drug-related decline in cellular immunity to VZV. VZV-induced neuronal destruction and inflammation causes the principal problems of pain, interference with activities in daily living, and reduced quality of life in elderly patients. Recently, attempts to reduce or eliminate HZ pain have been bolstered by the findings of clinical trials that antiviral agents and corticosteroids are effective treatment for HZ and that tricyclic antidepressants, topical lidocaine, gabapentin, and opiates are effective treatment for PHN. Although these advances have helped, PHN remains a difficult condition to prevent and treat in many elderly patients. Comment by Miles Day, M.D. This article reviews the epidemiology clinical features diagnosis and treatment of acute herpes zoster. It also describes the treatment of postherpetic neuralgia. While this is a good review for the primary care physician, the discussion for the treatment for both acute herpes zoster and postherpetic neuralgia do not mention invasive therapy. It is well documented in pain literature that sympathetic blocks with local anesthetic and steroid as well as subcutaneous infiltration of active zoster lesions not only facilitate the healing of acute herpes zoster but also prevents or helps decrease the incidence of postherpetic neuralgia. All patients who present to the primary care physician with acute herpes zoster should have an immediate referral to a pain management physician for invasive therapy. The treatment of postherpetic neuralgia is a challenging experience both for the patient and the physician. While the treatments that have been discussed in this article are important, other treatments are also available. Regional nerve blocks including intercostal nerve blocks, root sleeve injections, and sympathetic blocks have been used in the past to treat postherpetic neuralgia. If these blocks are helpful, one can proceed with doing crynourlysis of the affected nerves or also radio-frequency lesioning. Spinal cord stimulation has also been used for those patients who are refractory to noninvasive and invasive therapy. While intrathecal methylprednisolone was shown to be effective in the study quoted in this article one must be cautious not to do multiple intrathecal steroid injections in these patients. Multilple intrathecal steroid injections can lead to archnoiditis secondary to the accumulation of the steroid on the nerve roots and in turn causing worsening pain. [source] | |||||||||||||