Pendular Nystagmus Definition


Pendular Nystagmus:

Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)

Synonym: periodic alternating nystagmus, jerk nystagmus, horizontal nystagmus, fatigable positional nystagmus, dissociated nystagmus, convergence nystagmus, conjugate nystagmus, vertical nystagmus, unidirectional nystagmus, temporary nystagmus, symptomatic nystagmus, spontaneous ocular nystagmus, see saw nystagmus, rotational nystagmus, rotary nystagmus, retraction nystagmus, rebound nystagmus, permanent nystagmus, pathologic nystagmus, non-fatigable positional nystagmus, multidirectional nystagmus.