The eye movement disorders of progressive supranuclear palsy

In addition to the gross disturbances of vertical gaze, patients with progressive supranuclear palsy may show abnormalities in the saccadic and pursuit subsystems of horizontal gaze. Saccades are slower and smaller than normal. An attempt to elicit a large amplitude saccade will often result in a series of "fractionated" saccades. Pursuit eye movements become saccadic. The quick phases of vestibular and optokinetic nystagmus are of low amplitude. In the study presented, eye movements of 13 patients were recorded clinically and by electro-oculography, and data from the two methods, compared.