Search results for " Nerve"
showing 10 items of 885 documents
The location by early auditory evoked potentials (EAEP) of acoustic nerve and brainstem demyelination in multiple sclerosis (MS).
1980
Tone pips of suprathreshold intensities elicit an acoustic nerve response (I) and six low amplitude brainstem potentials (II-VII) during the initial 10 ms. Seven waves were studied in 40 control subjects and 5 waves (I-V) in 47 patients with MS. The results suggest involvement of the auditory pathway of 24 of 27 patients in the clinically "definite", of 5 of 9 cases in the "probable" and in none of 5 patients in the "possible" MS groups. EAEPs were normal in 6 cases with a spinal form with one exception where changes of potential were indicative of a midbrain lesion. Dysfunction within the acoustic pathway was observed at the level of the acoustic nerve and in the medulla oblongata, pons an…
Idiopathic intracranial hypertension: orbital MRI
1995
The case is reported of a patient with idiopathic intracranial hypertension examined with magnetic resonance imaging. Marked enhancement of the optic nerve heads was found, which might be related to blood-retinal barrier breakdown related to a sudden rise in intracranial cerebrospinal fluid pressure.
Alteration of Neuromuscular Function After a Prolonged Road Cycling Race
2003
The aim of this study was to characterize neuromuscular fatigue in knee extensor muscles after a prolonged cycling exercise. During the two days preceding a 140-km race (mean +/- SD duration: 278.2 +/- 24.9 min) and 15 to 30 min after, maximal percutaneous electrical stimulations were applied to the femoral nerve of 11 trained cyclists. Electrically evoked superimposed twitches and trains of 6 stimulations were delivered during isometric maximal voluntary contraction (MVC) to determine maximal voluntary activation (% VA). Knee extensors MVC decreased with fatigue from 158.2 +/- 29.6 to 144.2 +/- 30.0 Nm (p < 0.01), but no central activation failure was detected after the race. The average r…
Surgically verified variations in the A1 segment of the anterior cerebral artery
1991
✓ Two patients with rare variations of the A1 segment of the anterior cerebral artery are presented. One patient had a perforation of the optic tract by an abnormal course of the A1 segment, and the other harbored an aneurysm of the A1 segment running below the optic nerve. The authors present a summary of A1 segment variations described in the literature.
Treatment of chronic mandibular dislocations by eminectomy: follow-up of 10 cases and literature review.
2008
Introduction: Temporomandibular joint (TMJ) dislocation is defined as an excessive forward movement of the condyle beyond the articular eminence, with complete separation of the articular surfaces and fixation in that position. Objectives: To report ten cases treated by eminectomy for chronic mandibular dislocations, to evaluate the results of these surgeries and make a critical review of the literature. Methods: The sample was obtained from the records of the Department of Oral and Maxillofacial Surgery, University of Pernambuco and comprises cases submitted to chronic mandibular dislocation treatment by eminectomy between 2002 and 2007. Pre- and postoperative assessment included a thoroug…
Trismus resulting from central nervous system lesion.
1976
Three cases of unusual trismus are reported, occurring in patients with lesions of the central nervous system. On the basis of the clinical and electromyographical findings and observation of the course of the trismus this is interpreted as a symptom of a lesion of the brain stem, causing a dis-synergism of the masticatory muscles.
Malignant Peripheral Nerve Sheath Tumor With Osseous Heterologous Differentiation in Uncommon Locations (Heart and Retropharynx)
2016
We report two cases of malignant peripheral nerve sheath tumor (MPNST) in an uncommon location (heart and retropharynx) both with divergent osseous heterologous differentiation. We present the pathological and immunohistochemical studies that confirmed the neurogenic origin. The histopathology of the tumor arising in the retropharynx showed a transition from a neurofibroma to MPNST, making this a new report of an MPNST arising from a plexiform neurofibroma without neurofibromatosis. Primary cardiac MPNST with osseous differentiation has never been reported before. In conclusion, the histology of MPNSTs is very heterogeneous, showing no specific diagnostic immunoprofile or genetic alteration…
Fatigue and Recovery After High-Intensity Exercise Part I: Neuromuscular Fatigue
2004
The contribution of central and peripheral factors to muscle fatigue were quantified following a high-intensity uphill running exercise. Eight male volunteers performed an intermittent exercise at 120 % of maximal aerobic speed on a treadmill with an 18 % grade. Electrically evoked and voluntary contractions of the knee extensors and EMG of the two vastii were analyzed before and immediately after the high-intensity exercise. Isometric maximal voluntary contraction decreased slightly (-7+/-8 %; p < 0.05) after exercise but no changes were found in the level of maximal activation or in the torque produced by a 80 Hz maximal stimulation applied to the femoral nerve. Following exercise, the si…
Effect of electromyostimulation training on soleus and gastrocnemii H- and T-reflex properties.
2003
When muscle is artificially activated, as with electromyostimulation (EMS), action potentials are evoked in both intramuscular nerve branches and cutaneous receptors, therefore activating spinal motoneurons reflexively. Maximal soleus and gastrocnemii H- and T-reflex and the respective mechanical output were thus quantified to examine possible neural adaptations induced at the spinal level by EMS resistance training. Eight subjects completed 16 sessions of isometric EMS (75 Hz) over a 4-week period. Maximal soleus and gastrocnemii M wave (M(max)), H reflex (H(max)) and T reflex (T(max)) were compared between before and after training, together with the corresponding plantar flexor peak twit…
Electrical and mechanical H(max)-to-M(max) ratio in power- and endurance-trained athletes.
2001
The aim of this study was to compare the mechanical and electromyographic (EMG) characteristics of soleus motor units activated during maximal H reflex and direct M response among subjects with different histories of physical activity. Power-trained athletes produced stronger twitches, with a higher rate of twitch tension buildup and relaxation, than their endurance counterparts for both maximal H-reflex and maximal M-wave responses. The maximal H-reflex-to-maximal M-wave ratios for both force output (twitch) and EMG wave amplitude were significantly lower in power-trained than endurance-trained athletes. However, power-trained athletes exhibited a significantly greater twitch-to-EMG ratio…