Motor unit number index (MUNIX) in myopathic disorders: Clinical correlations and potential pitfalls.

Our aim was to study motor unit number index (MUNIX) in myopathic disorders. We studied 11 patients with myopathy, and healthy controls. We obtained MUNIX, compound muscle action potential (CMAP), motor unit size index (MUSIX) and alpha (α, power exponent from MUNIX equation) measurements from three different muscles.

Optimal E2 (reference) electrode placement in fibular motor nerve conduction studies recording from the tibialis anterior muscle.

Introduction: In this study we aimed to determine the contribution of the E2 (reference electrode) to the compound muscle action potential (CMAP) amplitude during fibular motor recording to the tibialis anterior (TA) when E2 is placed over routine referential vs. alternative sites.

Methods: The CMAP was obtained from 10 healthy subjects, using the active electrode (E1) over sites routinely used as E2 for the TA, whereas the E2 was over the contralateral knee.

Motor unit number index and neurophysiological index as candidate biomarkers of presymptomatic motor neuron loss in amyotrophic lateral sclerosis.

Introduction: Our objective was to determine the utility of motor unit number index (MUNIX) and neurophysiological index (NI) as surrogate biomarkers of disease progression in limbs without clinical signs of lower motor neuron (LMN) involvement from patients with slowly progressive amyotrophic lateral sclerosis (ALS).

Methods: Patients with slowly progressive ALS and at least 1 clinically unaffected limb were prospectively enrolled. Clinical signs of LMN loss and results from hand-held dynamometer (HHD), revised ALS Functional Rating Scale (ALSFRS-R), mean-MUNIX (from 3 different muscles), and NI were longitudinally recorded.

Why averaging multiple MUNIX measures in the longitudinal assessment of patients with ALS?

Objective: To assess the impact of averaging multiple MUNIX trials on the follow-up of patients with amyotrophic lateral sclerosis (ALS).

Methods: We determined the percent relative change (%RC) of MUNIX, in healthy subjects and patients with ALS, by subtracting the MUNIX value in the second visit from the first. Both the mean of a set of three MUNIX (mean-MUNIX) and the first MUNIX sample (single-MUNIX) were evaluated.

Effects of the stimulus phase on the air-conducted ocular vestibular evoked myogenic potential in healthy subjects.

Objective: The study aimed to examine the effect of the stimulus phase of air-conducted sound on ocular vestibular evoked myogenic potentials (oVEMPs).

Methods: oVEMPs were recorded after air-conducted sounds (500Hz, 4ms duration), presented with initial condensation (positive), rarefaction (negative), and alternant polarities from 12 healthy subjects.

Results: Most responses showed a bifid n10 peak separated by ∼1.

MUNIX: Reproducibility and clinical correlations in Amyotrophic Lateral Sclerosis.

Objective: To study the reproducibility, diagnostic yield to detect denervation, and clinical correlations of the Motor Unit Number Index (MUNIX) in subjects with Amyotrophic Lateral Sclerosis (ALS).

Methods: MUNIX evaluation was performed in three muscles twice on the same day to assess reproducibility. Cut-off values for the MUNIX were based on data from 51 healthy subjects (controls) to evaluate the sensitivity of the technique to detect denervation in 30 subjects with ALS.

Improving the reproducibility of motor unit number index.

Introduction: Reproducibility is an important aspect of any method intended to be a marker of disease progression. In this study we investigated approaches for improving motor unit number index (MUNIX) reproducibility.

Methods: We used the intraclass correlation coefficient (ICC) and the coefficient of variation (CV) to study reproducibility in healthy subjects.

Pattern of Peripheral Nerve Involvement in Spinocerebellar Ataxia Type 2: a Neurophysiological Assessment.

Peripheral neuropathy is frequent in spinocerebellar ataxia type 2 (SCA2), but the pattern and characteristics of nerve involvement are still an unsettled issue. This study aimed to evaluate the prevalence, extent, and distribution of nerve involvement in SCA2 patients through neurophysiological studies. Thirty-one SCA2 patients and 20 control subjects were enrolled in this study.

Pattern of peripheral nerve involvement in Machado-Joseph disease: neuronopathy or distal axonopathy? A clinical and neurophysiological evaluation.

Objective: Neuropathy is a well-recognized feature in spinocerebellar ataxia type 3 (SCA3) or Machado-Joseph disease (MJD), but the pattern of neuropathy is still a matter of debate. This study aimed to evaluate peripheral nerve involvement in MJD patients. Neurophysiological and clinical data were analyzed to distinguish neuronopathy from length-dependent distal axonopathy.

Perceptions and electric senoidal current stimulation.

Objective: To analyze the relationship between perceptions and electrical senoidal current stimulation (ESCS).

Method: The study population comprise 100 healthy volunteers. ESCS of 5 Hz and 2 kHz were applied to the left index finger at one and 1.