[Oculomotor findings in the stages "on" and "off" in Parkinson disease patients]

To study the possible damage of oculomotor structures we have studied 10 patients affected by idiopathic Parkinson's disease with a clear on-off phenomena. All the patients were subjected to an electro-oculographic examination observing qualitative and quantitative parameters in both on and off phases. The two exams were carried out in the same morning. We observed the well known electro-oculographic pattern of parkinsonian syndrome: multiple steps saccades, pursuit alterations, absence of spontaneous or evoked nystagmus. Moreover the most relevant finding consisted in an improvement of some electro-oculographic features during the off phase, contrary to clinical evidence. Such results seem to suggest that oculomotor system is functionally separate from that which controls arm movements.