Search results for " Nerve"
showing 10 items of 885 documents
Nociceptive masseter inhibitory reflexes evoked by laser radiant heat and electrical stimuli
1997
Electrical stimulation of the mental nerve evokes two suppression periods SP1 and SP2 in masseter muscle activity bilaterally. In order to investigate a possible nociceptive origin of the suppression periods, we compared the reflex responses evoked by electrical stimulation and by selective activation of nociceptors in hairy skin using painful infrared laser stimuli. The SP was elicited during more than 90% maximal voluntary contraction. Thresholds for detection, pain, and SP in the mental nerve area were determined by the method of limits. A suppression period was evoked by laser stimuli in nine of ten subjects bilaterally. The mean onset latency was 46.9 ms, the mean duration 58.9 ms. The…
Deep pain thresholds in the distal limbs of healthy human subjects.
2003
Pressure pain thresholds (PPTs) in distal limbs have been under-investigated despite their potential clinical importance. Therefore, we compared PPTs over nail bed, bony prominences, and muscle in distal parts of upper and lower limbs. We investigated 12 healthy subjects using three handheld devices: a spring-loaded, analogue pressure threshold meter (PTM) with two operating ranges, and an electronic Algometer. PPTs were determined with three series of ascending stimulus intensities with a ramp of about 50 kPa/s. PPTs were normally distributed in logarithmic space. PPTs over different tissues varied significantly (ANOVA, p0.001): mean thresholds and 95% confidence intervals were 615 kPa (26…
Hand-arm vibration syndrome: clinical characteristics, conventional electrophysiology and quantitative sensory testing.
2013
Abstract Objective Workers exposed to vibrating tools may develop hand-arm vibration syndrome (HAVS). We assessed the somatosensory phenotype using quantitative sensory testing (QST) in comparison to electrophysiology to characterize (1) the most sensitive QST parameter for detecting sensory loss, (2) the correlation of QST and electrophysiology, and (3) the frequency of a carpal tunnel syndrome (CTS) in HAVS. Methods QST, cold provocation tests, fine motor skills, and median nerve neurography were used. QST included thermal and mechanical detection and pain thresholds. Results Thirty-two patients were examined (54 ± 11 years, 91% men) at the more affected hand compared to 16 matched contro…
Management of head and neck paragangliomas: review of 120 patients.
2008
Head and neck paragangliomas (PGL) are rare, mostly benign tumors. About 10% to 15% of PGL are caused by mutations in the succinate dehydrogenase genes B, C, or D and may appear multifocally.A retrospective review of 120 patients with 146 head and neck PGL, including 46 carotid body tumors (CBT), 13 vagal tumors, 55 jugulotympanic tumors (JTT), 25 tympanic tumors (TT) and 7 tumors in other locations are included. The internal carotid artery was preserved in 97.5% of CBT resections. Preservation of hearing was achieved in 92% of JTT and 88% of TT resections.According to our experience, the treatment of PGL must be individualized, taking into account the patient's age, medical condition, tumo…
Vestibular Decruitment
1993
Torok studied the ratio obtained between the responses to two different heat stimulation intensities of the same temperature. A decrease in response to the strong stimulus (i.e., a diminished ratio) was called "vestibular decruitment," and was regarded as a topodiagnostic indicator of central vestibular lesion, reflecting "adaptation" or "fatigue." The authors studied the reliability of vestibular decruitment obtained by Torok's technique in the indication of central vestibular pathology. Twenty-eight normal individuals and 30 patients previously diagnosed by other methods with diffuse pathology of the central nervous system were evaluated. The results obtained show that the two stimuli use…
Tuberculoid leprosy and Type 1 lepra reaction.
2008
Summary A patient is described with tuberculoid leprosy and Type 1 (lepra) reaction from Sicily a non-endemic region, who lived previously in Manila from 2000 to 2005. The skin lesions became acutely inflamed and edematous. The plaques were painless to touch or pinprick, and there was swelling of the nerves in the fibro-osseous tunnels under the surface of the skin, including both the ulnar nerve at the elbow, and the posterior tibial nerve (medial malleolus). During the course of electro-neurographic studies, conduction velocity in the motory nerves indicated a slowing-down. The diagnosis of leprosy was confirmed by residence in an endemic area for about 5 years, by simultaneous skin lesio…
TMS activation of interhemispheric pathways between the posterior parietal cortex and the contralateral motor cortex
2016
Using a twin coil transcranial magnetic stimulation (tc-TMS) approach we have previously demonstrated that facilitation may be detected in the primary motor cortex (M1) following stimulation over the ipsilateral caudal intraparietal sulcus (cIPS). Here we tested the interhemispheric interactions between the IPS and the contralateral motor cortex (M1). We found that conditioning the right cIPS facilitated contralateral M1 when the conditioning stimulus had an intensity of 90% resting motor threshold (RMT) but not at 70% or 110% RMT. Facilitation was maximal when the interstimulus interval (ISI) between cIPS and M1 was 6 or 12 ms. These facilitatory effects were mediated by interactions with …
Dipole Source Analyses of Early Median Nerve SEP Components Obtained From Subdural Grid Recordings
2010
The median nerve N20 and P22 SEP components constitute the initial response of the primary somatosensory cortex to somatosensory stimulation of the upper extremity. Knowledge of the underlying generators is important both for basic understanding of the initial sequence of cortical activation and to identify landmarks for eloquent areas to spare in resection planning of cortex in epilepsy surgery. We now set out to localize the N20 and P22 using subdural grid recording with special emphasis on the question of the origin of P22: Brodmann area 4 versus area 1. Electroencephalographic dipole source analysis of the N20 and P22 responses obtained from subdural grids over the primary somatosensor…
Oculopharyngeal muscular dystrophy in a northern German family linked to chromosome 14q, and presenting carnitine deficiency
1997
We report the evaluation of oculopharyngeal muscular dystrophy (OPMD) in a large northern German family, which can be traced back six generations and is unrelated to French-Canadian families. The symptoms in this family start at about 50 years of age and include dysphagia, bilateral ptosis, and in some cases a slowly progressive atrophy and weakness of other extraocular, facial or limb girdle muscles. The muscle biopsies showed the pathognomonic ultrastructural finding of characteristic intranuclear filaments. Linkage analysis confirmed that this family is also linked to chromosome 14q markers. Haplotype analysis revealed that a unique haplotype segregates with the disease which is differen…
Cerebral potentials elicited by mechanical stimuli to the human leg: influence of artifacts
1992
Mechanical stimulation with a reflex hammer was applied to the quadriceps muscle tendon of healthy volunteers and patients. The time-locked electrical signals were recorded from the scalp. In all cases, reproducible potentials could be recorded, with latencies in a range of 20 ms to 100 ms. The potentials recorded in patients under complete spinal anesthesia were similar to those derived before the anesthesia. In brain dead patients who showed absence of median nerve or posterior tibial nerve SEP, reproducible potentials after mechanical stimuli could be recorded as well. The results suggest that the hammer taps lead to mechanical shock waves which are propagated along the body producing ti…