Biomedical subjects

A Labarre-Vila

Publications and source records attributed to A Labarre-Vila.

4 recordsLinked to original sources

PubMed2004

[Surface electromyography procedure].

Surface electromyography (SEMG) is not yet able to substitute needle EMG for diagnosing neuromuscular diseases in our current clinical neurophysiological practice. Several research groups have been working to reach this goal. Thus, we already have available, though imperfect and open to criticism, tools to apply SEMG to follow-up studies of neuromuscular diseases. There are enough scientific data to integrate validated tools into EMG equipment, to provide recommended electrodes and developed techniques and methods for recording and analysing all SEMG components, so that we could study the suggested standardised parameters in our clinical routine context. Independently of the accuracy of clinical indications for the chosen methods, the requirements of sensitivity, specificity and reproducibility should be as substantial for ENG as for needle or surface EMG. They suppose an equal demanding procedure in doing exams and interpreting results. The respective contribution of ENG and needle or surface EMG is still to be confirmed. Respective value and limitations of the force measurements by manual or quantitative testing, functional scales, SEMG or motor unit number counting are not yet evaluated in follow-up studies of neuromuscular diseases.

Clinical Protocols↗

PubMed2003

Variation in the classification of polyneuropathies among European physicians.

OBJECTIVE: Considerable debate still exists regarding the classification of polyneuropathies (PNPs) into predominantly demyelinating, predominantly axonal loss, mixed or unclassified. This study was designed to determine the variation among physicians in the classification of PNPs by using the European Standardized Telematic tool to Evaluate Electromyography knowledge-based systems and Methods (ESTEEM) multicenter database. METHODS: Seven physicians from 6 laboratories in Europe sent a total of 156 prospectively collected cases of PNP with electromyography (EMG) data including diagnosis (examination diagnosis) to the database. Each physician interpreted the electrophysiological data from all cases (interpretation diagnosis) and a final diagnosis was given at the consensus meetings of the group (consensus diagnosis). RESULTS: Comparison of each physician's examination diagnosis with his/her interpretation diagnosis, i.e. intra-physician variation, showed a change towards less classified PNPs (P < 0.05). Interpretation diagnoses showed large inter-physician variation in the classification of PNPs. The consensus group was more cautious than individual physicians in classifying PNPs as mixed and axonal. The probability of the consensus diagnosis increased with increasing number of abnormal motor and sensory segments tested. CONCLUSIONS: Recognition of variation in classification of PNP as shown in this study and suggesting standards of good clinical practice developed by a consensus group may increase the quality of EMG practice.

Consensus↗

PubMed2001

Charcot-Marie-Tooth disease and sleep apnoea syndrome: a family study.

BACKGROUND: Charcot-Marie-Tooth (CMT) disease is a genetically heterogeneous group of hereditary motor and sensory polyneuropathies in which sleep apnoea has rarely been reported and no causal relation shown. We looked for an association between the most common subtype of CMT disease (CMT1A) and sleep apnoea syndrome. METHODS: Having diagnosed sleep apnoea and CMT in one family member (index case), we prospectively investigated 13 further members not previously suspected of having neuropathy or apnoeas. All had a neurological examination, electroneuromyography, polysomnography, and genetic testing for CMT disease. FINDINGS: 11 of the 14 family members had the autosomal dominant demyelinating form of CMT disease with PMP22 gene duplication on chromosome 17. Whatever their neurological disability, all 11 individuals had sleep apnoea syndrome with a mean (SD) apnoea-hypopnoea index of 46.6/h (28.5) of sleep (normal value <15/h). The remaining three family members were free from neuropathy and sleep apnoea syndrome. Sleep apnoea and neuropathy severity were highly correlated; the compound muscle action potential (CMAP) amplitude of the median nerve was inversely correlated with the apnoea-hypopnoea index (r=-0.69, p=0.029). The severity of neuropathy and sleep apnoea were higher in male CMT individuals and were correlated with age and body mass index. No wake or sleep diaphragmatic dysfunction was shown. INTERPRETATION: We think that sleep apnoea syndrome is related to a pharyngeal neuropathy. Upper airway dysfunction, previously described in the CMT2C subtype, might be a clinical expression of the CMT1A subtype, to which familial susceptibility could predispose.

Adolescent↗

PubMed2000

Exercise test in muscle channelopathies and other muscle disorders.

We studied the percentage change in compound muscle action potential (CMAP) amplitude and area during and after a 5-min maximal contraction of the muscle. The exercise test (ET) was performed on 64 patients with different muscle disorders and on 46 normal controls. The range of normal ET values was defined as the mean + 2 SD of the control values. The mean sensitivity of the test was 63% in the whole group with ion channel muscle disorders, the highest sensitivity being seen in primary periodic paralysis (81%) and the lowest in chloride channelopathies (17%). In thyrotoxic periodic paralysis, the ET was abnormal in the three of the four patients studied. In patients with myotonic dystrophy, a smaller than normal increase in CMAP amplitude occurred during and after exercise, whereas in proximal myotonic myopathy a normal initial increase in CMAP amplitude was followed by an abnormal decrement. We conclude that the ET can be of use in confirming abnormal muscle membrane excitability in patients with calcium and sodium channelopathies and thyrotoxic periodic paralysis. In chloride channelopathy, the test may also be abnormal, but shows no, or only a small, increase in amplitude or area in the immediate postexercise period. The test may also be abnormal in proximal myotonic myopathy, but is normal in myotonic dystrophy.

Action Potentials↗