Fig. 16. Electro-oculographic recording in the right eye of a patient with bilateral internuclear ophthalmoplegia. Abduction saccades to the right (r) are rapid, whereas adduction saccades to the left (l) are slow. Abduction nystagmus at arrow. Upper tracing: eye position; lower tracing: peak velocity. (Metz HS: Saccadic velocity measurements in internuclear ophthalmoplegia. Am J Ophthalmol 81:296, 1976. Published with permission from the American Journal of Ophthalmology. Copyright by the Ophthalmic Publishing Company)