Faciomandibular myoclonus during sleep: video-EEG recording rule out epilepsy as a cause of nocturnal tongue biting

Abstract

Introduction Nocturnal tongue biting as an isolated entity has been rarely reported. In the few published cases has not been possible to observe the tongue biting itself. The aim of this communication is the presentation of a patient in whom this symptom was dramatically presented due to its intensity and frequency and in which after several studies we were able to confirm eventually the tongue biting using video-EEG recording in a day nap. Materials and methods A 18 year old boy had been presenting, since 12 year old, several episodes per week of nocturnal tongue biting during sleep. He has a past history of a severe traffic crash with craneoencephalic trauma, but without evident lesions in the MRI. Seriated EEGs were performed in basal conditions or after sleep deprivation and a photo paroxistic response with generalized discharges was evidenced at intermediate photostimulation frecuencies (10–15 Hertzs). Anticonvulsant therapy was initiated that controlled the episodes, reappearing after the withdrawal. At that moment, a video-EEG recording was performed. Results During the video-EEG study the patient presented one episode of tongue biting during sleep, without the presence of epileptiform abnormalities in the EEG. In this basis, the episodes were diagnosed as facio-mandibular myoclonus. Conclusion During sleep, several motor activities affecting oro-facial musculature have been described, both physiological and pathological entities. Apart from the facio-mandibular myoclonus, the differential diagnosis comprises the orofacial automatisms, the bruxism, the epilepsy or the parasomnias with rhythmic or periodic movements. In our case, the final diagnosis was delayed and several treatments were essayed, and this allowed us to analyze the response to them.