Quantitative CMAP shape analysis differentiates between uniform and non-uniform motor nerve conduction slowing

Objective: Demyelination may cause a uniform reduction of the conduction velocity of all fibres of a peripheral nerve segment, or may non-uniformly affect only some nerve fibres while sparing others. In the latter case the routinely determined nerve conduction velocity (NCV) is normal while amplitude, duration, and shape of compound muscle action potentials (CMAP) vary with the distance between the stimulus and the muscle. This study was done to determine if and to what extent quantitative analysis of CMAP shapes has the potential to differentiate between uniform and non-uniform conduction slowing. Methods: Data…