Acquired convergence-evoked pendular nystagmus in multiple sclerosis

Nystagmus seen only with convergence is unusual. We describe four cases of acquired convergence-evoked pendular nystagmus in patients with multiple sc lerosis. The nystagmus was horizontal and asymmetric in all patients. Eye m ovement recordings in one subject showed a conjugate rather than a converge nt-divergent,ent relationship of the phase of movement between the two eyes . All patients had evidence of optic neuropathy and cerebellar dysfunction. Occlusion of either eye during fixation of near targets led to divergent d rift of the covered eve and a decrease in nystagmus. intravenous scopolamin e reduced nystagmus in one patient. East-in prisms alleviated symptoms of o scillopsia at near and improving reading visual acuity. Convergence-evoked pendular nystagmus may be more common than currently appreciated, particula rly among patients with multiple sclerosis.