[Case of extraocular muscle paralysis with changes of the ragged-red fiber type]

The authors describe a case of progressive paresis of the extraocular muscles in a 57-year-old woman followed up since 1974. There were no abnormalities in the biochemical investigations, EEG, EMG, ECG, pneumoencephalography and tests for myasthenia. Only in fragments of the biceps brachii muscle histological and histochemical investigations showed mitochondrial changes of the type of "ragged-red fibres". The authors review the literature pertinent to different syndromes of paralysis of the external eye muscles. This is the first case published in the Polish literature.