Vertical optokinetic nystagmus in Parkinson's disease

✍ Scribed by Christopher M. Knapp; Irene Gottlob; Rebecca J. McLean; Yusuf A. Rajabally; Richard J. Abbott; Suzanne Rafelt; Frank A. Proudlock

• Book ID: 102945262
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 816 KB
• Volume: 24
• Category: Article
• ISSN: 0885-3185
• DOI: 10.1002/mds.22634

✦ Synopsis

Abstract

Parkinson's disease (PD) is associated with a number of oculomotor deficits; however, little is known about changes in vertical optokinetic nystagmus (OKN) associated with PD. We recorded eye movements in 14 PD patients and 14 age‐matched controls in response to large field OKN stimulation using stimulus velocities of 20°/second and 40°/second. We compared asymmetry of horizontal and vertical responses in the two groups. We found vertical OKN to be strongly asymmetric in PD with reduced gains for downward‐moving stimuli. This asymmetry was significantly greater than that recorded in control volunteers. We postulate that this could result from an abnormal pursuit/early OKN system in PD leading to greater influence of the delayed OKN system. © 2009 Movement Disorder Society