Neuromas

Association of Pain, neuropathic pain is defined as pain initiated or caused by a primary lesion, dysfunction in the nervous system". Neuropathy can be divided broadly into peripheral and central neuropathic pain, depending on whether the primary lesion or dysfunction is situated in the peripheral or central nervous system. In the periphery, neuropathic pain can result from disease or inflammatory states that affect peripheral nerves (e.g. diabetes mellitus, herpes zoster, HIV) or alternatively due to neuroma formation (amputation, nerve transection), nerve compression (e.g. tumours, entrapment) or other injuries (e.g. nerve crush, trauma). Central pain syndromes, on the other hand, result from alterations in different regions of the brain or the spinal cord. Examples include tumour or trauma affecting particular CNS structures (e.g. brainstem and thalamus) or spinal cord injury. Both the symptoms and origins of neuropathic pain are extremely diverse. Due to this variability, neuropathic pain syndromes are often difficult to treat. Some of the clinical symptoms associated with this condition include spontaneous pain, tactile allodynia (touch-evoked pain), hyperalgesia (enhanced responses to a painful stimulus) and sensory deficits. 

Neurofibromatosis type 2 is characterized by acoustic neuromas and caf6-au-lait spots. It is caused by mutations in a tumor suppressor gene on chromosome 22. 

Ma, W., and Quirion, R. (2006). Increased calcitonin gene-related peptide in neuroma and invading macrophages is involved in the up-regulation of interleukin-6 and thermal hyperalgesia in a rat model of mononeuropathy. J. Neurochem. 98, 180—192. 

Peripheral nerve block is created by injecting ethanol around the selected nerve. The effect of alcohol on nerve tissue has been examined in animal models and in postmortem specimens from patients who received neurolytic blocks (8,9). In general, alcohol causes destruction of nerve fibers, with subsequent Wallerian degeneration. The basal lamina around the Schwann cell usually remains intact. This leaves a tract available for axon regeneration without the formation of a neuroma. If the cell bodies are completely destroyed, regeneration will not occur. Contact of alcohol with unintended nerve roots underlies many of the more serious complications. Involvement of anterior rootlets sufficient to interrupt motor nerve function will result in muscle weakness or paralysis. Interruption of... 

Familial dysplastic nevi Neuroma Pheochromocytoma Malignant melanoma... 

Devor M, Keller CH, DeerinckTJ, Levinson SR, EllismanMH 1989 Na channel accumulation on axolemma of afferent endings in nerve end neuromas in Apteronotus. Neurosc Lett 102 149-154... 

England JD, Happel LT, Kline DG et al 1996 Sodium channel accumulation in humans with painful neuromas. Neurology 47 272—276... 

Chabal C, Russell LC, Burchiel KJ 1989 The effect of intravenous lidocaine, tocainide, and mexiletine on spontaneously active fibers originating in rat sciatic neuromas. Pain 38 333—338... 

Devor M, Wall PD, Catalan N 1992 Systemic lidocaine silences ectopic neuroma and DRG discharge without blocking nerve conduction. Pain 48 261-268... 

S trie hart / Aren t those data from neuromas ... 

Medullary carcinoma of thyroid, phacochromocytoma. and multiple mucosal neuromas tire present in MEN type llh. The presence ofthe.se neuromas on the tongue, lips or buccal mucosa is the most consistent feature. Neuromas are also... 

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