[Cataract in a young patient].

Myotonic dystrophy Curschmann-Steinert is a genetic disease which is inherited in an autosomal dominant pattern. Patients usually suffer from myotonia, muscular atrophy and weakness and myopathic facies. Furthermore, patients often present with ophthalmological symptoms with subcapsular cataract and bilateral ptosis being the most frequent ones. Therefore the ophthalmologist can help to detect patients suspected of having this disease and initiate further investigations. Despite clinically distinct findings, the disease is often overlooked because of the diversity of symptoms and clinical manifestations.