In case of peripheral facial palsy, electroneuromyogram of the facial nerve provides an indication of the nature (myelinic and/or axonal) and severity of nerve damage, thereby facilitating establishment of a prognosis, which is favorable for myelin damage, and guarded for severe axonal damage. The initial examination must be carried out during the second week. In case of severe axonal damage, examination results can be monitored at the third, and more particularly the sixth and the twelfth months. Stable neurophysiological data between the sixth and the twelfth months signal damage stability and open the way to possible palliative surgery. In the event of trigeminal damage, neurophysiological exploration furthers analysis of temporal muscle innervation. ENMG can confirm and precisely indicate peripheral hemifacial spasm.