A Patient with Olivopontocerebellar Atrophy Combined with Sleep Apnea Syndrome.

Sleep apnea syndrome is frequently associated with multiple system atrophy, for example olivopontocerebellar atrophy (OPCA), and sometimes causes the sudden death of such patients.A 60-year-old man with olivopontocerebellar atrophy was admitted to Jichi Medical School Hospital. With the progress of his disease, heavy snoring and apnea attacks were observed during sleep. Vocal cord movements were analyzed by laryngofiberscopy during both wakefulness and sleep induced by intravenous administration of diazepam. While waking-laryngofiberscopy showed a normal movement of the vocal cords, sleeping-laryngofiberscopy showed an obvious paradoxical movement of the vocal cords, where the vocal cords abducted during expiration and adducted during inspiration. To prevent choking, a tracheostomy was done. After the tracheostomy, the vocal cord movements got worse during both wakefulness and sleep.Paradoxical movement of the vocal cords appears to be caused by the following : 1) a disorder of the respiratory center in the medulla oblongata, 2) a decrease of CO2-sensitivity in chemical receptors during sleep, and 3) an abnormal tension of the intralaryngeal muscles. Tracheostomy should be considered in such patients, but there is still room for further study on the indications for the operation.