1218 Obstructive Sleep Apnea Due To Oromandibular Dystonia And Treated With Botulinum Toxin

Abstract

Abstract Introduction Abnormalities of the upper airway are an underrecognized cause of obstructive sleep apnea (OSA). Oromandibular dystonia (OMD) is characterized by involuntary contractions of the masticatory, facial, pharyngeal or laryngeal muscles usually resulting in pain, dysarthria, dysphagia, or impaired mastication. We present a patient with OMD manifest as episodic OSA and sleep maintenance insomnia treated effectively with botulinum toxin injections of the temporalis and masseter muscles. Report of Case A 51-year-old man was referred for fatigue and insomnia. History was notable for prior facial trauma requiring jaw surgeries with titanium prostheses and chronic OMD requiring periodic botulinum toxin injections of the temporalis and masseter muscles. An initial home sleep test (HST) 43 days after the last botulinum toxin injection showed a respiratory event index of 6.5 events/hour. Given severity of symptoms, positive airway pressure (PAP) was initiated; however, due to poor tolerance and persistent symptoms, he was referred for attended polysomnography (PSG). The PSG was done 13 days after an injection and showed apnea-hypopnea index (AHI) of 0 events/hour. Because the patient continued to endorse episodically severe symptoms that he felt paralleled the severity of OMD and waning of botulinum toxin effect, a repeat PSG was performed at a subjective botulinum toxin effect nadir. This PSG done at 83 days post-injection demonstrated AHI of 84 events/hour. PAP therapy was thus resumed, and the patient’s symptoms improved with increased frequency of botulinum toxin treatments. Conclusion To our knowledge, this is the first report of OSA due to chronic dystonia of the facial muscles. Botulinum toxin has demonstrated benefit in the treatment of OMD with efficacy generally lasting three to six months. While PAP remains the first-line treatment for OSA, in patients with structural or functional abnormalities of the upper airway, it is important to also consider treatment of the underlying anatomical defect.