Laryngeal myoclonus is a rare involuntary movement characterized by persistent, repetitive and rhythmic contraction of laryngeal muscles. It is not in itself a disease entity but is a symptom found in various diseases. Two cases of pharyngo-laryngeal myoclonus that we observed were introduced and palato-pharyngo-laryngeal myoclonus literature was reviewed. So far there have been 304 case reports from 18 months to 91 years old (avg 44.5) having a male preponderance of 59% : 41% in America and Europe, and 65 case reports (2 to 76 years old, avg 30) had a sex distribution of male 62% : female 38% in Japan. Presenting complaints were earclick, involuntary movements and abnormal sounds in the cervix and et al, and some patients had no self-evident symptom. Almost all cases of myoclonus were observed in the soft palate. One of the characteristics of myoclonus was its resistance to many influences such as medication, sleep, and even coma, while it was influenced under some conditions. MRI was useful to detect the lesions. Many pathoanatomical findings demonstrated lesions of the dantato-olivary pathway and the pseudohypertropy of the inferior olivary nucleus. The pathophysiological mechanisms are still unclear and more physiological studies are needed in order to establish treatments.
