| 1. |
- Kouyoumdjian, Joao A., et al.
(författare)
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Concentric needle jitter in stimulated frontalis in 20 healthy subjects
- 2012
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Ingår i: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 45:2, s. 276-278
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Tidskriftsartikel (refereegranskat)abstract
- Normative data for jitter parameters using a disposable concentric needle have been presented in a few studies. Jitter, expressed as the mean consecutive difference (MCD), was measured in the frontalis muscle in 20 subjects by percutaneous bar stimulation of the temporal nerve branch. The mean MCD for individual studies (20) and for all potentials (600) were 16.05 +/- 2.73 mu s and 16.05 +/- 5.96 mu s, respectively. The suggested limit for mean MCD is 22 mu s and for outliers is 28 mu s.
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| 2. |
- Kouyoumdjian, Joao Aris, et al.
(författare)
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Concentric needle jitter on stimulated frontalis and extensor digitorum in 20 myasthenia gravis patients
- 2011
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Ingår i: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 44:6, s. 912-918
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Our objective was to study jitter parameters using a concentric needle electrode (CNE) in the extensor digitorum (ED) and frontalis (FR) muscles. Methods: Twenty myasthenia gravis (MG) patients, mean age 44.5 years, were studied. Percutaneous (FR) and intramuscular needle (ED) stimulation approaches were used. Jitter was expressed as the mean consecutive difference (MCD). The filter settings were from 1000 HZ to 10 kHZ. Results: Abnormal MCD was found in 85% for both ED and FR and in 90% when combining the two muscles. An abnormal percentage of outliers was found in 90% for ED and 85% for FR. The mean MCD did not show a difference for ED and FR, but the percentage of outliers and blocking were higher in FR. Abnormality was found in 93.7% (generalized) and in 75% (ocular) of MG cases. For ED outliers abnormality was greater than the MCD. Conclusion: CNE jitter is reliable for investigation of MG, although borderline findings should be judged with caution.
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| 3. |
- Kouyoumdjian, Joao Aris, et al.
(författare)
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Concentric needle jitter on stimulated Orbicularis Oculi in 50 healthy subjects
- 2011
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Ingår i: Clinical Neurophysiology. - : Elsevier BV. - 1388-2457 .- 1872-8952. ; 122:3, s. 617-622
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aim of this study was to estimate the jitter parameters in healthy controls in stimulated Orbicularis Oculi (OOc) muscle using concentric needle electrode (CNE). Methods: Fifty healthy subjects, 13 males and 37 females (21-56 years, mean age of 38 +/- 9.2 years) were studied. The zygomatic branch of facial nerve was stimulated with a bar electrode. Jitter was expressed as the mean consecutive difference (MCD). Filter settings 1000 Hz-10 kHz. Results: The mean MCD from individual studies (n = 50, Gaussian distribution) was 21.5 +/- 1.99 mu s (median = 21 mu s), ranging from 17.8 to 26 mu s (upper limit, 97.5%, 25.5 mu s). The mean and median MCD from all potentials (n = 1500, non-Gaussian distribution) were 21.6 and 21 mu s, ranging from 7.1 to 39 mu s (upper limit, 97.5%, 33.4 mu s). Conclusions: Suggested practical limits in the OOc for mean MCD was 26 mu s and for outliers 34 mu s. Significance: Stimulation jitter recordings with CNE could be used in practice but borderline findings should be judged with great caution until larger database obtained with uniform setting available.
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| 4. |
- Kouyoumdjian, Joao A., et al.
(författare)
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Concentric needle jitter on voluntary activated frontalis in 20 healthy subjects
- 2013
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Ingår i: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 47:3, s. 440-442
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Normative data for jitter parameters using a disposable concentric needle have been described in a few studies. Methods: Jitter, expressed as the mean consecutive difference (MCD), was measured in the frontalis muscle in 20 subjects by voluntary contraction. Results: Mean MCD for individual studies (20, Gaussian), all potentials (400, non-Gaussian), and 18th highest value (20, Gaussian) were 19.9 +/- 2.9 s, 19.9 +/- 6.6 s, and 26.9 +/- 4.4 s, respectively. Conclusion: The suggested upper normal limit for mean MCD is 26 s and for outliers is 36 s.
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| 5. |
- Nandedkar, Sanjeev D., et al.
(författare)
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Motor unit number index (MUNIX) : principle, method, and findings in healthy subjects and in patients with motor neuron disease
- 2010
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Ingår i: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 42:5, s. 798-807
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Tidskriftsartikel (refereegranskat)abstract
- The motor unit number index (MUNIX) is a method for assessment of number and size (MUSIX) of motor units (MUs) using the compound muscle action potential (CMAP) and surface electromyographic interference pattern (SIP). This method was used to study the hypothenar muscle in 34 healthy subjects to define normal range, and to study reproducibility. Four healthy subjects and 13 patients with amyotrophic lateral sclerosis (ALS) were studied serially over a 1-year period. In healthy subjects, MUNIX showed good reproducibility. In serial studies, healthy subjects showed no change in the CMAP amplitude and MUNIX. ALS patients with minimal change in CMAP amplitude had a significant drop in MUNIX and increase in MUSIX, indicating MU loss compensated by reinnervation. When the CMAP changed significantly (>30%) in 1 year, the CMAP and MUNIX decreased in parallel. MUNIX would be useful to study MU loss in degenerative diseases of motor neurons.
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| 6. |
- Nandedkar, Sanjeev D., et al.
(författare)
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Reproducibility of munix in patients with amyotrophic lateral sclerosis
- 2011
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Ingår i: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 44:6, s. 919-922
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: In this study we investigated the reproducibility of motor unit number index (MUNIX) in patients with amyotrophic lateral sclerosis (ALS). Methods: MUNIX was recorded in patients with ALS. Studies were performed in 18 thenar and 18 hypothenar muscles by two operators. The reproducibility was assessed using mean MUNIX values, linear regression, correlation coefficient, and coefficient of variation (COV) in individual studies. Results: The mean values showed no significant difference. The linear regression showed a strong correlation. Most patients had low COV. A high COV was seen when MUNIX was very low. The COV was higher in thenar than in hypothenar muscles. Conclusions: MUNIX has very good reproducibility in ALS patients. COV may exaggerate interoperator variation when MUNIX is very low. The higher variability in the thenar muscle is also due to variability in compound muscle action potential amplitude. Although both muscles show good reproducibility, the hypothenar is better suited for serial studies in individual patients.
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