[Mitochondrial oculopharyngeal myopathy: description of a case].

We describe a 55 years old man affected by eyelid ptosis, mild ophthalmoplegia externa and severe dysphagia owing to pharyngoesophageal dyskinesia. Skeletal and eyelid constrictor muscles EMG showed myogenic alterations. Muscle histological findings of ragged red fibers and oxidative histochemical alterations, together with ultrastructural investigation clue for mitochondrial myopathy diagnosis. This, considering the unusual clinical aspects of the case, confirms as mitochondrial disease can widely vary in their phenotypical expression.