1/42. hyperalgesia with reduced laser evoked potentials in neuropathic pain.Nociceptive evoked potentials to laser stimuli (LEPs) are able to detect lesions of pain and temperature pathways at peripheral, spinal and supraspinal levels. It is commonly accepted that LEP attenuation correlates with the loss of pain and temperature sensations, while pathological heat-pain hypersensitivity has been associated with increased LEP amplitude. Here we present two patients in whom increased pain sensation (hyperalgesia) to laser stimuli was, on the contrary, associated to delayed, desynchronized and attenuated LEPs. Both patients experienced increased unpleasantness and affective reactions to laser, associated to poor ability to localize the stimulus. In both cases the results may be explained by an overactivation of the 'medial pain system', in one patient due to deafferentation of cortical sensory areas by a capsular lesion, and in the other to imbalance between A-delta and C fiber excitation due to peripheral nerve injury. Our results suggest that LEPs, as currently recorded, reflect the activity of a 'lateral' pain system subserved by rapidly conducting fibers. They may therefore, assess the sensory and cognitive dimensions of pain, but may not index adequately the affective-emotional aspects of pain sensation conveyed by the 'medial' pain system. The dissociation between pain sensation and cortical EPs deserve to be added to the current semiology of LEPs, as the presence of abnormal pain to laser on the background of reduced LEPs substantiates the neuropathic nature of the pain.- - - - - - - - - - ranking = 1keywords = sensation (Clic here for more details about this article) |
2/42. A new ambulatory foot pressure device for patients with sensory impairment. A system for continuous measurement of plantar pressure and a feed-back alarm.Abnormal and excessive plantar pressure is a major risk factor for the development of foot ulcers in patients with loss of protective pain sensation. Repeated pressure with each step can result in inflammation at specific points, followed by ulcer formation. patients with peripheral nerve disease are unable to prevent the development of such lesions, which often lead to amputation. For this reason, it has been suggested that a fundamental therapeutic intervention should be the reduction of high plantar pressure. We have developed a portable, battery-operated ambulatory foot pressure device (AFPD) which has two important functions: (1) to determine the areas of high plantar pressure, and (2) to provide an acoustic alarm, adjusted to a specific pressure load, which is triggered when weight-bearing exceeds the predetermined plantar pressure. A memory of plantar pressure parameters allows for downloading of the data and sequential analysis during the investigation period. Such an alarm device could replace the lack of pain sensation and may play an important role in the prevention of ulcer development and lower extremity amputation.- - - - - - - - - - ranking = 0.5keywords = sensation (Clic here for more details about this article) |
3/42. Isolated sural neuropathy presenting as lateral ankle pain.A case of job-related, unilateral traumatic sural neuropathy causing severe lateral ankle pain and impaired work performance for a 26-yr-old female grocery clerk is reported. This diagnosis is made both clinically and electrophysiologically. We review the pertinent electrophysiologic features, anatomy, and clinical findings in our patient with an isolated sural neuropathy. A review of the literature demonstrates that trauma is the most common cause of this unusual isolated neuropathy. Despite its rare occurrence, it should be considered in patients who present with lateral ankle pain and concomitant loss of sensation in the sural nerve distribution. The establishment of a neuropathic origin assists with management strategies that will differ from the more common musculoskeletal causes of lateral ankle pain. After an appropriate diagnosis and treatment, an excellent outcome resulted for our patient.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
4/42. Peripheral neuropathy in chronic occupational inorganic lead exposure: a clinical and electrophysiological study.BACKGROUND AND OBJECTIVES: Traditionally the neuromuscular disorder associated with lead poisoning has been purely motor. This study assessed peripheral nerve function clinically and electrophysiologically in 46 patients with neuropathic features out of a total population of 151 workers with raised blood and/or urinary lead concentrations. RESULTS: Average duration of occupational exposure for the neuropathic group ranged from 8-47 years (mean 21.7). Their mean blood lead concentration (SD) was 63.9 (18.3) microg/dl (normal <40), urinary lead 8.6 (3.3) microg/dl (normal<5.0), urinary coproporphyrins 66.7 (38.4) microg/g creatinine (20-80), urinary aminolaevulinic acid 1.54 (0.39) mg/g creatinine (0.5-2.5). All 46 had distal paraesthesiae, pain, impaired pin prick sensation, diminished or absent ankle jerks, and autonomic vasomotor or sudomotor disturbances. Reduced vibration sensation and postural hypotension were present in all 20 studied. None of these 46 patients had motor abnormalities. Motor conduction velocity and compound muscle action potential amplitudes were normal, with marginally prolonged distal motor latencies. Sensory nerve action potential amplitudes lay at the lower end of the normal range, and the distal sensory latencies were prolonged. No direct correlation was found between the biochemical variables, and the clinical or electrophysiological data. CONCLUSIONS: One additional patient was seen with shorter term exposure to lead fumes with subacute development of colicky abdominal pain, severe limb weakness, and only minor sensory symptoms. Unlike the patients chronically exposed to lead, he had massively raised porphyrins (aminolaevulinic acid 21 mg/g creatinine, coproporphyrins 2102 microg/g creatinine). patients with unusually long term inorganic lead exposure showed mild sensory and autonomic neuropathic features rather than the motor neuropathy classically attributed to lead toxicity. It is proposed that the traditional motor syndrome associated with subacute lead poisoning is more likely to be a form of lead induced porphyria rather than a direct neurotoxic effect of lead.- - - - - - - - - - ranking = 0.5keywords = sensation (Clic here for more details about this article) |
5/42. Peripheral neuropathy associated with weekly oral 5-fluorouracil, leucovorin and eniluracil.5-fluorouracil (5-FU)-associated neurotoxicity is uncommon; symptoms may occur abruptly or more gradually during the course of chemotherapy. Peripheral neuropathy with 5-FU therapy has only rarely been reported. Two patients treated in a phase I trial of oral 5-FU, leucovorin and eniluracil, an inhibitor of dihydropyrimidine dehydrogenase (DPD), developed delayed onset symptoms of unsteady gait and reduced sensation in the legs. magnetic resonance imaging scans of the brain and neurologic examination did not support a CNS basis for the condition. Electromyograms and nerve conduction studies revealed sensorimotor polyneuropathy. Other common etiologies of peripheral neuropathy were excluded. The neurological condition of these patients stabilized after 5-FU dose reduction and partial resolution gradually occurred when protocol therapy was stopped. Although CNS symptoms may rarely complicate 5-FU therapy, peripheral neuropathy is unexpected. patients with DPD deficiency treated with conventional doses of 5-FU typically develop acute CNS toxicity shortly after therapy, accompanied by extremely high systemic exposure to 5-FU. patients with normal 5-FU clearance may also experience CNS toxicity, particularly with high-dose schedules, and both parent drug and its catabolites may be contributory. Since DPD was profoundly inhibited during eniluracil therapy in these two patients, it is likely that 5-FU or its active metabolites were contributing factors to the peripheral neuropathy.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
6/42. Heterotopic ossification of peripheral nerve ("neuritis ossificans"): report of two cases.OBJECTIVE AND IMPORTANCE: Heterotopic ossification ("neuritis ossificans") is among the least frequently encountered reactive lesions in peripheral nerves. Only two cases have been described previously, one in the median nerve of a 34-year-old man, and the other in the ulnar nerve of an adult woman. The architecture of this lesion is distinctly zonal. Consisting of a central fibroblastic core, an intervening zone of osteoid production, and a peripheral layer of ossification, the pattern is remarkably similar to that of myositis ossificans. This similarity and the occurrence of the process in superficial nerves have led to speculation that trauma plays a role in its pathogenesis; this hypothesis remains unproved. We describe two additional cases of neuritis ossificans. CLINICAL PRESENTATION: One patient, a 41-year-old man, experienced pain and numbness in the left leg for several months but had no history of local trauma. A mass was detected in the saphenous nerve. The second patient, a 16-year-old boy, noted subacute onset of pain in the popliteal fossa and decreased sensation in the distribution of the lateral sural cutaneous nerve. A mass was found within the tibial nerve at the knee level. INTERVENTION: In each patient, resection of the mass required sacrifice of a segment of the nerve. CONCLUSION: In each patient, the mass was composed of fibrovascular tissue with osteoid and bone deposition arranged in a zonal pattern. The ossifying process was intraneural but encased rather than directly involving nerve fascicles. These exceptionally intact examples of neuritis ossificans underscore its resemblance to myositis ossificans. Nerve-sparing resection of such masses is not always possible.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
7/42. Alcohol neurolysis for persistent pain caused by superior cluneal nerves injury after iliac crest bone graft harvesting in orthopedic surgery: report of four cases and review of the literature.STUDY DESIGN: Harvesting of autologous bone graft from the posterior iliac crest for lumbar spinal fusions is a frequently performed procedure in orthopedic surgery. The most common complication associated with this procedure is an alteration in sensation over the donor site manifested as chronic pain, hyperesthesia, dysesthesia, or diminished sensitivity resulting from superior cluneal nerve (SCN) injury. OBJECTIVE: To predict the effectiveness of alcohol neurolysis in the treatment of persistent pain caused by the entrapment of superior cluneal nerves. SUMMARY AND BACKGROUND DATA: The subjects of this study were patients with intractable pain in donor area after conventional treatments using a transverse incision, which is parallel to posterior iliac crest. The study group was composed of four patients who underwent surgery in a 1-year period and experienced chronic pain resulting from superior cluneal nerve injury. methods: No reports describing alcohol neurolysis of the superior cluneal nerve exist in the relevant literature. All four patients in this study were treated with alcohol neurolysis of the superior cluneal nerves. RESULTS: The study patients were observed up to 4 years, and none of them reported any problems. CONCLUSIONS: The authors suggest that conventional treatments be limited to a 2-month period, and that alcohol neurolysis be applied as soon as possible to prevent lengthy pain experiences.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
8/42. Silicone gel infiltration of a peripheral nerve and constrictive neuropathy following rupture of a breast prosthesis.Following rupture of a subpectoral breast prosthesis, massive amounts of silicone gel migrated into the arm of a patient. The patient developed painful paresthesias and decreased sensation in the cutaneous distribution of the superficial radial nerve. Nerve conduction studies showed both an increase in distal latency and decreased amplitude in this nerve compared with the normal opposite side. Subsequent neurolysis confirmed dense fibrosis surrounding the nerve. Silicone droplets also were observed within the thickened epineurium of the median nerve, but no electrophysiologic evidence of neuropathy occurred. Multiple debridements of the subcutaneous tissue of the arm were necessary. In one of these specimens, histologic sections demonstrated silicone gel infiltration of a subcutaneous nerve. This is the first reported case of silicone gel infiltration of a nerve and constrictive neuropathy associated with a prosthesis rupture.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
9/42. Amyloid polyneuropathy with transthyretin Arg50 in a Japanese case from Osaka.A Japanese patient with systemic amyloidosis associated with a transthyretin (TTR) variant Arg50 is presented. This 41-year-old man became impotent and developed decreased pain sensation in his hands, and then sensory loss and muscle wasting in his lower legs, and cardiomyopathy appeared. The symptoms progressed and he died of congestive heart failure at age 46. There were amyloid deposits in all organs studied and massive amyloid deposition was seen in the peripheral nerves and cardiac muscles. Amyloid fibrils extracted from heart tissue contained TTR. A genetic mutation, causing a Ser50-->Arg substitution of the TTR molecule, was identified in another family member. plasma TTR was shown to be a mixture of normal TTR Ser50 and mutant TTR Arg50 in the 2 subjects.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
10/42. Levetiracetam in the treatment of neuropathic pain: three case studies.case reports: A 55-year-old woman presented with numbness and pain in both lower extremities. The pain was of sudden onset and of 4 months' duration. A nerve conduction study demonstrated a bilateral sensorimotor peripheral neuropathy with axonal and demyelinating features of a mild degree. Initial treatment with oral thiamine and topiramate had little efficacy and caused unacceptable side effects. A switch to 1500 mg bid levetiracetam plus nortriptyline resulted in a 60% improvement in pain symptoms. A 75-year-old man presented with numbness in both feet of 5 years' duration. The sensation of numbness had progressed to persistent pain, resulting in sleep disruption. The patient's use of oral thiamine did not lead to pain relief, but the addition of 500 mg levetiracetam once in the evening led to a complete resolution of his pain and to sleep improvement. A 67-year-old obese male was referred from a podiatrist with progressive dysfunction in both lower extremities that developed over a 1-year period. walking more than a few steps resulted in sharp, shooting pain that at night disrupted sleep. A nerve conduction study demonstrated a severe bilateral sensorimotor peripheral neuropathy with axonal and demyelinating features. Treatment with 1000 mg levetiracetam bid resulted in complete absence of pain. CONCLUSIONS: In these 3 case studies, levetiracetam was demonstrated to be an effective therapy in the treatment of neuropathic pain. It has the benefits of a low incidence of adverse events and an improvement in patients' sleep.- - - - - - - - - - ranking = 0.25keywords = sensation (Clic here for more details about this article) |
| | Next -> |