1379 Orofacial Dyskinesia Producing Video-Polysomnographic Artifact in a Patient Undergoing Evaluation for Obstructive Sleep Apnea

Introduction Orofacial dyskinesia is an uncommon movement disorder characterized by involuntary, repetitive, stereotypical movement of the face, tongue, and jaw. These movements may mimic or confound sleep-related motor abnormalities and can create artifact during polysomnography (PSG). Recognition of this entity is important to avoid misinterpretation of sleep studies. We describe a case in which orofacial dyskinesia generated facial and oral movement artifact during video PSG performed for the evaluation of suspected obstructive sleep apnea (OSA). Report of case(s) A 77-year-old male with past medical history significant for hypertension, hyperlipidemia, diabetes mellitus type 2, coronary artery disease, psoriasis, psoriatic arthritis, and remote history of sarcoidosis who underwent polysomnogram for evaluation of snoring, witnessed apneas and excessive daytime sleepiness. There was no recorded use of anti-psychotics, anti-depressants, anti-convulsant or anti-Parkinsonian agents. Most of his teeth were intact on oral examination. No significant snoring or sleep disordered breathing events were noted on attended overnight video PSG. Apnea-hypopnea index was 3.6 events per hour. Frequent periodic limb movement of sleep were observed (PLM index 43.1/hour; PLM arousal index 1.8/hour). Review of synchronized video revealed frequent, rhythmic, movements of the lips, perioral muscles, and mandible during wakefulness after arousal, which disappeared with drowsiness and sleep. These movements produced intermittent electromyographic (EMG) and 1 Hz EEG artifact. The involuntary movements were consistent with orofacial dyskinesia. Conclusion Orofacial dyskinesia can introduce artifact during video polysomnography. Possible differential for these movements include edentulous and non-edentulous orofacial dyskinesia, tardive dyskinesia, seizure disorder, bruxism and glossokinetic artifact. Awareness of this condition and careful review of synchronized video are essential for accurate diagnosis. Sleep clinicians should consider orofacial dyskinesia in edentulous and non-edentulous patients with unexplained facial or oral movements observed during polysomnography. Support (if any) None