18 research outputs found
Anti-neuronal antibodies associated with headache with neurological deficits and cerebrospinal fluid lymphocytosis
5OCT333-335
Abnormal neuromuscular transmission in cluster headache
Objective.-To identify and investigate any dysfunction of neuromuscular transmission in episodic cluster headache
Surface stimulation single-fiber electromyography in myasthenia gravis
Surface stimulation for single-fiber electromyography has been proposed previously as a novel technique based on a study performed on healthy subjects. The current study was designed to determine the diagnostic value of surface stimulation single-fiber electromyography in patients with myasthenia gravis. Ten patients with myasthenia gravis were recruited for the study. Surface stimulation of the facial nerve trunk. as well as extramuscular needle stimulation of its zygomatic branch was performed. Twenty single-fiber potentials were recorded from the orbicularis oculi muscle for each stimulation type in each patient. For both stimulation techniques, mean jitter values and the total number of abnormal individual junctions were found to be abnormally high. Jitter values obtained by surface stimulation were comparable with those obtained by needle stimulation
Tek Lif Elektromiyografisi Yoluyla Tendondan Kayıtlama ile Lif Çapı Deǧişkenliǧinin Elektriksel Aktiviteye Etkisinin Araştırılması
Medical Technologies National Conference (TIPTEKNO) --OCT 15-18, 2015 -- Bodrum, TURKEYWOS: 000380505200107In this preliminary study, two muscle fibers which one of them had a constant fiber diameter and the other had a variable fiber diameter were created by using an EMG simulator. Single Muscle Fiber Action Potentials (SMFAPs) were recorded either from the vicinity of the neuromuscular junction or near the tendon. It was intended to reveal the relationship between the time dispersions of these electrical activities and the differences of muscle fiber diameters. Hence it is considered that the the difference between the diameters of muscle fibers contributing to these electrical activities can be estimated
Analysis of Gastrocnemius Compound Muscle Action Potential in Rat after Death: Significance for the Estimation of Early Postmortem İnterval
Evaluation of neuromuscular transmission by using monopolar needle electrode
Objective: To evaluate the value of single-fibre electromyography (SFEMG) with monopolar electrode (MNPE) in revealing neuromuscular transmission dysfunction. Material and methods: We examined the extensor digitorum communis muscle by using single-fibre electrode (SFE) and MNPE sequentially, in randomly assigned 20 healthy volunteers and in 17 patients with known myasthenia gravis (MG). The high-pass filter setting was 3 kHz for MNPE. Ten individual jitter values were calculated for each electrode in every muscle. Repetitive nerve stimulation (RNS) test on trapezius muscle was performed on 15 patients. Results: In controls, the mean jitter values were 27 +/- 9 (10-59) mu s with SFE, and 21 +/- 7.2 (9-56) mu s with MNPE (P = 0.001). In the MG group, the mean jitter values were 52.4 +/- 38 (12-221) mu s with SFE, and 51.8 +/- 34.7 (12-179) mu s with MNPE. Both electrodes identified junction dysfunction in 14 patients. RNS revealed decrement in four patients but 11. Conclusion: SFEMG with SFE is still the gold standard; however, SFEMG with MNPE is superior to RNS like SFEMG with SFE
Motor Unit Territories in Juvenile Myoclonic Epilepsy Patients
In this study, the scanning EMG technique was implemented to investigate electrophysiological cross-sections of the motor unit (MU) territories in healthy volunteers and in subjects with juvenile myoclonic epilepsy and spinal muscular atrophy. Measurements were taken intramuscularly by means of two concentric needle electrodes from biceps brachialis muscles. 3-D maps of the MU territories were plotted for each MU to determine the lengths of MU cross-section and the maximum amplitudes of each MU. There was evidence of a preponderance of large MUs in patients with juvenile myoclonic epilepsy
Effect of triggering potential on calculations of jitter in single-fiber EMG
Jitter values are calculated in reference to a triggering potential during single-fiber electromyography (SFEMG) performed during voluntary contraction. When there are more than two single-fiber action potentials (SFAP) and the selected triggering potential is from an abnormal end-plate, all the jitters calculated from the same trace will be affected. In this study, the effect of triggering potential on calculated jitter was investigated in myasthenic and healthy volunteers by switching the triggering potential and recalculating the jitter off-line. Selecting a triggering potential from an abnormal end-plate increased the number of abnormal individual jitters as well as the mean jitter, Therefore, if the equipment software has the capacity to change the trigger potential, the triggering potential should not be from an abnormal end-plate if all possible jitter values are to be calculated for traces having three or more single-fiber potentials. Otherwise, only one jitter value should be included from any one trace to prevent false-positive results. (C) 2002 Wiley Periodicals, Inc
Development of a Method to Analyze Compound Action Potential (CMAP) Scan Used in the Diagnosis and Monitoring of Neuromuscular Diseases
Göker, İmran (Arel Author)Motor Unit Number Estimate (MUNE) is a quantitative method which has been developed to determine the axon number as close as possible to the real axon number. It is used to assess and to monitor neuromuscular diseases such as anterior horn diseases. The Electrophysiological muscle scan is based on recording Compound Muscle Action Potentials (CMAPs) as response of the muscles innervated by the nerves being stimulated by gradually increased electrical currents. The purpose of this study is to develop a method which will ensure the MUNE by the analysis of the data obtained via electrohysiological muscle scan. CMAPs which were generetaed as a result of gradual stimulation in simulator software were recorded. The absolute values of the differences of CMAPs and the ratio of the mean of these values to the maximum CMAP value were computed through a software created in MATLAB to calculate MUNE values. Hence, it was intended to determine the relationship between the real axon count and MUN