[Clinical value of electroretinographic tests in Parkinson's disease (author's transl)].

The authors studied the behaviour of the b wave in the ERG in patients with Parkinson's disease treated with L-Depa (Sinemet). The results demonstrated that a significant reduction of the voltage of the b wave coincides with a therapeutic overdose and side-effects of the neuropsychiatric type. The authors recommend, therefore, that a periodic ERG examination should be conducted in patients with Parkinson's disease during the course of treatment in order to prevent reactions from pharmacological overdosage.