Differentiation between single fiber potentials from one muscle fiber or contaminated by other fibers using discriminating function

ObjectivesThe aim was to improve the identification of potentials recorded using single fiber electromyography (SFEMG) contaminated by potentials from other muscle fibers, which might affect measured jitter value, by defining more selective criteria of single fiber potential (SFP) discrimination. We were looking for solutions suitable for automatization.MethodsStandard parameters characterizing SFP and their combinations were analyzed to define an analytical discriminating function able to verify if potentials recorded using SFEMG are due to single fiber or due to two (or more) fibers.ResultsThe discriminating function is based on combination of standard SFP parameters. The procedure was tested on a set of simulated i.e., known data and on samples of clinical data. The tests on simulated data confirmed assumed properties of discriminating function. Preliminary results of pilot studies using patient data suggest its ability for differentiation between potentials of one fiber and contaminated ones. The procedure is suitable for automatization.ConclusionResults suggest that proposed discriminating function when supplementing standard criteria would help to promote SFP recordings and enable to improve relevancy of jitter measurements and of jitter value norms.