Clinical and electrophysiological abnormalities in the visual system in myotonic dystrophy.

The investigation comprised 16 patients with verified myotonic dystrophy. The patients were examined ophthalmologically, by electroretinography (ERG) and pattern visual-evoked potentials (VEPs). The results were compared to those of a normal control group. More than 50% of the patients had changes in their lenses or retinas, and the ERGs and VEPs were frequently abnormal. No statistical relation was found between the clinical and electrophysiological findings, and the pattern of abnormalities seemed to vary at random. The number of abnormal clinical and electrophysiological findings increased slightly with the age of the patients, but no statistically significant relation was found either to the patients' age or the duration of the disease.