Page 126 - The Indian Optician Digital Edition March-April 2021

nystagmus blockage syndrome)

z Miscellaneous (spasmus nutans, congenital
motor nystagmus and periodic alternating
nystagmus)
CLASSIFICATION (STRABISMIC):
NYSTAGMUS ASSOCIATED WITH
STRABISMUS
1. Congenital Nystagmus - can be sensory
or motor

A. Sensory Nystagmus: The cause of sensory
nystagmus is loss of foveal fixation due
to an organic abnormality of the media,
macula, retina, or optic nerve. Patients with
sensory nystagmus tend to have poor vision
from organic causes in addition to limited
foveation time resulting from nystagmus.
B. Motor Nystagmus: This term is used when
CONGENITAL MOTOR NYSTAGMUS
there is no sensory cause. As the fovea is
unaffected, the vision tends to be better.
Some of them may even have 6/6 vision. 2. Latent Nystagmus - This condition is
also defined as a bilateral congenital jerk
This condition is usually present from an
nystagmus. The nystagmus is more obvious
early age and is often associated with squint.
upon occluding one eye. It may have head
It may be pendular initially and jerky later.
turn towards the fixing eye. Tiny oscillations
It is abolished during sleep. The amplitude are present even when viewing binocularly. It
and frequency of congenital motor is often associated with infantile esotropia.
nystagmus increases with stress, particularly
emotional stress. 3. Nystagmus block syndrome - In some cases
of infantile esotropia, there is purposive
excessive convergence to damp down
congenital nystagmus – this is revealed when
OPTOKINETIC NYSTAGMUS
the convergence has been treated surgically.
MANAGEMENT OF NYSTAGMUS:

INDICATIONS:
z To improve vision
z For correction of abnormal head posture
z For management of associated squint

REFRACTIVE ERRORS AND AMBLYOPIA
FROM NYSTAGMUS

In a number of cases, it is found that
nystagmus is associated with some or more
degree of refractive errors or sometimes
amblyopia. It is therefore, mandatory to be
alert while examining nystagmus patients
because sometimes some clinicians do not

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