EEG IN DYSTROPHIA MYOTONICA

EEGs were recorded from 49 patients with dystrophia myotonica, 25 male and 24 female from 11 to 60 years of age. Pathological EEGs were obtained from 23 patients, 11 male and 12 female. The main finding was a slowing of the background activity. Some focal abnormalities, mainly slow waves, were recorded from 9 patients including 3 patients with focal spikes or slow waves. None of them had epileptic seizures. In the normal EEG tracings the frequency of the alpha activity was a bit slower than in the normal population. The slowing of the alpha rate was somewhat proportional to the ventricular enlargement proved by pneumoencephalography in 30 patients. Only in 6 patients both the electroencephalograms and pneumoencephalograms were described as normal. The follow-up study in 17 patients showed that the anatomical abnormalities in some cases were preceded by electroence-phalographical disturbances. These findings indicate an involvement of the central nervous system in a very high percentage (88 %) of patients with dystrophia myotonica. © 1969 S. Karger AG, Basel.