Quantitative Electromyography of the Frontalis Muscle

Abstract

Purpose: Identification of abnormal motor unit potentials (MUP), in particular those caused by myopathic processes, is generally difficult in facial muscles because the MUPs are already low in amplitude and short in duration. Therefore, quantitative measures for the limits of abnormality are needed more frequently for these muscles, especially for the pathological processes predominantly affecting the craniofacial area. In this study, we aimed to determine some quantitative values that may help us to differentiate "myogenic" and "neurogenic" processes in periocular muscles.