Thirty-four patient s with an identified muscular disease were referred to our department for assessment and treatment of swallowing difficulties. Their ages ranged from 16to 91 years (mea n 59). The diagnoses were oculopharyngeal dystrophy in 17 patients, Steinert myotonic dystrophy in 6, mitochondri almyopathies in 4, polymyositis in 3, and other types in 4 patients. The main consequences of the dysphagia were weight loss (12 patients), pulmonary infections (15 patients), modified food consistency (18 patients) and non-oral feeding (3 patients). Several techniques were used to assess the different stages of deglutition: physical examination during swallowing, videofluoroscopy, pharyngoesophagealmanometry, videofibroscopy ofthe pharynx during swallowing. Major pathological features found in the pharynx were decreased pharynx peristaltis and impaired UES relaxation. Cricopharyngeal myotomy was performed in II myopathic patients (median follow-up 24.9months), while it was unnecessary, refused or contraindicated in the other patients. The procedure was successful in 8 patients whose dysphagia was dramatically improved, and failed in 3 patients. Pharyngeal perstalti s was severely impaired only in the 3 failures and was partly preserved in the improved cases. We conclude that pharyngeal function is the major prognostic factor. Cricopharyngeal myotomy is an effective treatment in those cases where cricopharyngeal dysfunction is a predominant problem or where pharyngeal peristaltis is partly impaired, since the procedure removes one obstacle. It is contraindicated when pharynx propulsion is severely impaired.