due to cerebellar disease
The nystagmus is jerky with large amplitude and low frequency.
It may be present in the primary position. The nystagmus
increases when the eyes look in the direction of the
Other additional examination:
mention to the examiner that you would like to test for other
cerebellar signs such as scanning speech, intention
tremor, past-pointing, disdianochokinesia and wide-based
mention you would like to test the hearing and corneal sensation
for possible cerebellopontine lesion
ask to examine the fundus for optic atrophy (as cerebellar
signs and optic neuritis are common in multiple sclerosis)
List some of the nystagmus with localizing signs.
There is nystagmus in the primary position with the fast
phase beating downward. The nystagmus remains down-beating
in different directions of gaze. Lateral gaze usually
accentuates the nystagmus.
mention that the nystagmus is associated with cervicomedullary
lesion such as Arnold-Chiari malformation. Examine the
back of the neck for any surgical scar.
What are the causes of a down-beat nystagmus?
There is torsional nystagmus in the primary position.
When one eye elevates and intorts the other depresses and extorts
and vice-versa. This typical of lesion in chiasmal region.
mention you would like to examine the visual field for bitemporal
There is pendular nystagmus in the primary position. This
may be horizontal, vertical or rotary. The nystagmus decreases on
convergence but increases on covering one eye. There
may be abnormal eye posture in an attempt to keep the eyes in the null
mention to the examiner that you would like to examine the
anterior segment for congenital cataract, aphakia from
previous cataract operation, albinism, aniridia or corneal
abnormalities. Also examine the posterior segment for
optic nerve hypoplasia, dragged discs from retinopathy
of prematurity and foveal hypoplasia.
How would you manage a child with congenital nystagmus?