ID 347 – Facial myokymia in devic disease

Abstract

Introduction Neuromyelitis optica, also known as Devic disease,is one of the inflammatory idiopathic demyelinating diseases of the central nervous system. Involuntary abnormal movements have been described in this disease. Patient We describe a 49 y/o woman, diagnosed of neuromyelitis optica, with positive immunoglobulin G, NMO Ig G, targeting aquaporin 4 water channel, and presenting for the last five years with involuntary, rippling, wavelike, continuos left facial movements. Results Needle EMG demostrated many myokymic discharges in orbicularis oculi y oris muscles on the left. The discharges ranged form doublets to triplets recurring several times per second. Motor units within bursts fired between 25 and 100 Hz. Discussion The involunary fine movements of left facial muscles here described, associated with myokimic discharges on the needle EMG, can be the expression of a change in the microenvironment of the axon membrane with a hiperexcitable ectopic generator, caused by demyelination of the root of facial nerve in the brainstem.